Multilocus sequence typing reveals a novel subspeciation of Lactobacillus delbrueckii.

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Tanigawa, Kana; Watanabe, Koichi

2011-03-01

Currently, the species Lactobacillus delbrueckii is divided into four subspecies, L. delbrueckii subsp. delbrueckii, L. delbrueckii subsp. bulgaricus, L. delbrueckii subsp. indicus and L. delbrueckii subsp. lactis. These classifications were based mainly on phenotypic identification methods and few studies have used genotypic identification methods. As a result, these subspecies have not yet been reliably delineated. In this study, the four subspecies of L. delbrueckii were discriminated by phenotype and by genotypic identification [amplified-fragment length polymorphism (AFLP) and multilocus sequence typing (MLST)] methods. The MLST method developed here was based on the analysis of seven housekeeping genes (fusA, gyrB, hsp60, ileS, pyrG, recA and recG). The MLST method had good discriminatory ability: the 41 strains of L. delbrueckii examined were divided into 34 sequence types, with 29 sequence types represented by only a single strain. The sequence types were divided into eight groups. These groups could be discriminated as representing different subspecies. The results of the AFLP and MLST analyses were consistent. The type strain of L. delbrueckii subsp. delbrueckii, YIT 0080(T), was clearly discriminated from the other strains currently classified as members of this subspecies, which were located close to strains of L. delbrueckii subsp. lactis. The MLST scheme developed in this study should be a useful tool for the identification of strains of L. delbrueckii to the subspecies level.

DNA Probe for Lactobacillus delbrueckii

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Delley, Michèle; Mollet, Beat; Hottinger, Herbert

1990-01-01

From a genomic DNA library of Lactobacillus delbrueckii subsp. bulgaricus, a clone was isolated which complements a leucine auxotrophy of an Escherichia coli strain (GE891). Subsequent analysis of the clone indicated that it could serve as a specific DNA probe. Dot-blot hybridizations with over 40 different Lactobacillus strains showed that this clone specifically recognizes L. delbrueckii subsp. delbrueckii, bulgaricus, and lactis. The sensitivity of the method was tested by using an α-32P-labeled DNA probe. Images PMID:16348233

In Vitro Inhibition of Klebsiella pneumoniae by Lactobacillus delbrueckii Subsp. delbrueckii LDD01 (DSM 22106): An Innovative Strategy to Possibly Counteract Such Infections in Humans?

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Mogna, Luca; Deidda, Francesca; Nicola, Stefania; Amoruso, Angela; Del Piano, Mario; Mogna, Giovanni

To determine the in vitro antimicrobial activity of selected Lactobacillus strains isolated from the feces of healthy humans against Klebsiella pneumoniae. Klebsiella is ubiquitous in nature and may colonize the skin, the pharynx, or the gastrointestinal tract of humans. Despite the widespread use of antibiotic molecules with a broad spectrum in hospitalized patients, an increased overall load of klebsiellae as well as the subsequent development of multidrug-resistant strains able to synthesize extended-spectrum beta-lactamase have been registered. These strains are particularly virulent, express capsular-type K55, and have a considerable ability to propagate. The 4 strains Lactobacillus paracasei LPC01 (CNCM I-1390), Lactobacillus rhamnosus LR04 (DSM 16605), Bifidobacterium longum B2274 (DSM 24707), and Lactobacillus delbrueckii subsp. delbrueckii LDD01 (DSM 22106) were tested. The analysis was performed using both a disc-diffusion assay and the broth-dilution procedure, also including an evaluation of the supernatants obtained from a fresh broth culture of each bacterium. L. delbrueckii subsp. delbrueckii LDD01 demonstrated the best inhibitory results among all the tested strains. The antibacterial activity of the supernatant was retained even after treatment with α-amylase and neutralization with NaOH 1N, thus suggesting the protein structure of the inhibitory molecule. In contrast, it was completely lost after treatment with proteinase K. Overall results suggest that the inhibitory effect of L. delbrueckii subsp. delbrueckii LDD01 should be attributed to the production of a bacteriocin. This strain may be prospectively useful for strengthening probiotic formulations and possibly counteract infections by K. pneumoniae in humans.

A new methodology for rapid detection of Lactobacillus delbrueckii subsp. bulgaricus based on multiplex PCR.

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Nikolaou, Anastasios; Saxami, Georgia; Kourkoutas, Yiannis; Galanis, Alex

2011-02-01

In this study we present a novel multiplex PCR assay for rapid and efficient detection of Lactobacillus delbrueckii subsp. bulgaricus. The accuracy of our method was confirmed by the successful identification of L. delbrueckii subsp. bulgaricus in commercial yoghurts and food supplements and it may be readily applied to the food industry. Copyright © 2010 Elsevier B.V. All rights reserved.

Lactobacillus delbrueckii subsp. bulgaricus CRL 454 cleaves allergenic peptides of β-lactoglobulin.

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Pescuma, Micaela; Hébert, Elvira M; Haertlé, Thomas; Chobert, Jean-Marc; Mozzi, Fernanda; Font de Valdez, Graciela

2015-03-01

Whey, a cheese by-product used as a food additive, is produced worldwide at 40.7 million tons per year. β-Lactoglobulin (BLG), the main whey protein, is poorly digested and is highly allergenic. We aimed to study the contribution of Lactobacillus delbrueckii subsp. bulgaricus CRL 454 to BLG digestion and to analyse its ability to degrade the main allergenic sequences of this protein. Pre-hydrolysis of BLG by L. delbrueckii subsp. bulgaricus CRL 454 increases digestion of BLG assayed by an in vitro simulated gastrointestinal system. Moreover, peptides from hydrolysis of the allergenic sequences V41-K60, Y102-R124, C121-L140 and L149-I162 were found when BLG was hydrolysed by this strain. Interestingly, peptides possessing antioxidant, ACE inhibitory, antimicrobial and immuno-modulating properties were found in BLG degraded by both the Lactobacillus strain and digestive enzymes. To conclude, pre-hydrolysis of BLG by L. delbrueckii subsp. bulgaricus CRL 454 has a positive effect on BLG digestion and could diminish allergenic reactions. Copyright © 2014 Elsevier Ltd. All rights reserved.

Draft Genome Sequence of Lactobacillus delbrueckii subsp. bulgaricus CRL871, a Folate-Producing Strain Isolated from a Northwestern Argentinian Yogurt.

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Laiño, Jonathan Emiliano; Hebert, Elvira María; Savoy de Giori, Graciela; LeBlanc, Jean Guy

2015-06-25

Lactobacillus delbrueckii subsp. bulgaricus CRL871 is the first strain of L. delbrueckii subsp. bulgaricus reported as a folate-producing strain. We report the draft genome sequence of L. delbrueckii subsp. bulgaricus CRL871 (2,063,981 bp, G+C content of 49.1%). This strain is of great biotechnological importance to the dairy industry because it constitutes an alternative to folic acid fortification. Copyright © 2015 Laiño et al.

Transcriptome-based characterization of interactions between Saccharomyces cerevisiae and Lactobacillus delbrueckii subsp. bulgaricus in lactose-grown chemostat cocultures.

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Mendes, Filipa; Sieuwerts, Sander; de Hulster, Erik; Almering, Marinka J H; Luttik, Marijke A H; Pronk, Jack T; Smid, Eddy J; Bron, Peter A; Daran-Lapujade, Pascale

2013-10-01

Mixed populations of Saccharomyces cerevisiae yeasts and lactic acid bacteria occur in many dairy, food, and beverage fermentations, but knowledge about their interactions is incomplete. In the present study, interactions between Saccharomyces cerevisiae and Lactobacillus delbrueckii subsp. bulgaricus, two microorganisms that co-occur in kefir fermentations, were studied during anaerobic growth on lactose. By combining physiological and transcriptome analysis of the two strains in the cocultures, five mechanisms of interaction were identified. (i) Lb. delbrueckii subsp. bulgaricus hydrolyzes lactose, which cannot be metabolized by S. cerevisiae, to galactose and glucose. Subsequently, galactose, which cannot be metabolized by Lb. delbrueckii subsp. bulgaricus, is excreted and provides a carbon source for yeast. (ii) In pure cultures, Lb. delbrueckii subsp. bulgaricus grows only in the presence of increased CO2 concentrations. In anaerobic mixed cultures, the yeast provides this CO2 via alcoholic fermentation. (iii) Analysis of amino acid consumption from the defined medium indicated that S. cerevisiae supplied alanine to the bacterium. (iv) A mild but significant low-iron response in the yeast transcriptome, identified by DNA microarray analysis, was consistent with the chelation of iron by the lactate produced by Lb. delbrueckii subsp. bulgaricus. (v) Transcriptome analysis of Lb. delbrueckii subsp. bulgaricus in mixed cultures showed an overrepresentation of transcripts involved in lipid metabolism, suggesting either a competition of the two microorganisms for fatty acids or a response to the ethanol produced by S. cerevisiae. This study demonstrates that chemostat-based transcriptome analysis is a powerful tool to investigate microbial interactions in mixed populations.

Regulation and Adaptive Evolution of Lactose Operon Expression in Lactobacillus delbrueckii

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Lapierre, Luciane; Mollet, Beat; Germond, Jacques-Edouard

2002-01-01

Lactobacillus delbrueckii subsp. bulgaricus and L. delbrueckii subsp. lactis are both used in the dairy industry as homofermentative lactic acid bacteria in the production of fermented milk products. After selective pressure for the fast fermentation of milk in the manufacture of yogurts, L. delbrueckii subsp. bulgaricus loses its ability to regulate lac operon expression. A series of mutations led to the constitutive expression of the lac genes. A complex of insertion sequence (IS) elements (ISL4 inside ISL5), inserted at the border of the lac promoter, induced the loss of the palindromic structure of one of the operators likely involved in the binding of regulatory factors. A lac repressor gene was discovered downstream of the β-galactosidase gene of L. delbrueckii subsp. lactis and was shown to be inactivated by several mutations in L. delbrueckii subsp. bulgaricus. Regulatory mechanisms of the lac gene expression of L. delbrueckii subsp. bulgaricus and L. delbrueckii subsp. lactis were compared by heterologous expression in Lactococcus lactis of the two lac promoters in front of a reporter gene (β-glucuronidase) in the presence or absence of the lac repressor gene. Insertion of the complex of IS elements in the lac promoter of L. delbrueckii subsp. bulgaricus increased the promoter's activity but did not prevent repressor binding; rather, it increased the affinity of the repressor for the promoter. Inactivation of the lac repressor by mutations was then necessary to induce the constitutive expression of the lac genes in L. delbrueckii subsp. bulgaricus. PMID:11807052

Factors Affecting Exocellular Polysaccharide Production by Lactobacillus delbrueckii subsp. bulgaricus Grown in a Chemically Defined Medium†

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Petry, Sandrine; Furlan, Sylviane; Crepeau, Marie-Jeanne; Cerning, Jutta; Desmazeaud, Michel

2000-01-01

We developed a chemically defined medium (CDM) containing lactose or glucose as the carbon source that supports growth and exopolysaccharide (EPS) production of two strains of Lactobacillus delbrueckii subsp. bulgaricus. The factors found to affect EPS production in this medium were oxygen, pH, temperature, and medium constituents, such as orotic acid and the carbon source. EPS production was greatest during the stationary phase. Composition analysis of EPS isolated at different growth phases and produced under different fermentation conditions (varying carbon source or pH) revealed that the component sugars were the same. The EPS from strain L. delbrueckii subsp. bulgaricus CNRZ 1187 contained galactose and glucose, and that of strain L. delbrueckii subsp. bulgaricus CNRZ 416 contained galactose, glucose, and rhamnose. However, the relative proportions of the individual monosaccharides differed, suggesting that repeating unit structures can vary according to specific medium alterations. Under pH-controlled fermentation conditions, L. delbrueckii subsp. bulgaricus strains produced as much EPS in the CDM as in milk. Furthermore, the relative proportions of individual monosaccharides of EPS produced in pH-controlled CDM or in milk were very similar. The CDM we developed may be a useful model and an alternative to milk in studies of EPS production. PMID:10919802

Streptococcus thermophilus urease activity boosts Lactobacillus delbrueckii subsp. bulgaricus homolactic fermentation.

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Arioli, Stefania; Della Scala, Giulia; Remagni, Maria Chiara; Stuknyte, Milda; Colombo, Stefano; Guglielmetti, Simone; De Noni, Ivano; Ragg, Enzio; Mora, Diego

2017-04-17

The proto-cooperation between Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus in the yogurt consortium enhances the growth rate and size of each population. In contrast, the independent growth of the two species in milk leads to a slower growth rate and a smaller population size. In this study, we report the first evidence that the urease activity of S. thermophilus increases the intracellular pH of L. delbrueckii in the absence of carbon source. However, in milk, in the presence of lactose the alkalizing effect of urea-derived ammonia was not detectable. Nevertheless, based on glucose consumption and lactic acid production at different pH in , L. delbrueckii showed an optimum of glycolysis and homolactic fermentation at alkaline pH values. In milk, we observed that ammonia provided by urea hydrolysis boosted lactic acid production in S. thermophilus and in L. delbrueckii when the species were grown alone or in combination. Therefore, we propose that urease activity acts as an altruistic cooperative trait, which is costly for urease-positive individuals but provides a local benefit because other individuals can take advantage of urease-dependent ammonia release. Copyright © 2016 Elsevier B.V. All rights reserved.

Molecular Characterization of Three Lactobacillus delbrueckii subsp. bulgaricus Phages

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Casey, Eoghan; Mahony, Jennifer; O'Connell-Motherway, Mary; Bottacini, Francesca; Cornelissen, Anneleen; Neve, Horst; Heller, Knut J.; Noben, Jean-Paul; Dal Bello, Fabio

2014-01-01

In this study, three phages infecting Lactobacillus delbrueckii subsp. bulgaricus, named Ld3, Ld17, and Ld25A, were isolated from whey samples obtained from various industrial fermentations. These phages were further characterized in a multifaceted approach: (i) biological and physical characterization through host range analysis and electron microscopy; (ii) genetic assessment through genome analysis; (iii) mass spectrometry analysis of the structural components of the phages; and (iv), for one phage, transcriptional analysis by Northern hybridization, reverse transcription-PCR, and primer extension. The three obtained phage genomes display high levels of sequence identity to each other and to genomes of the so-called group b L. delbrueckii phages c5, LL-Ku, and phiLdb, where some of the observed differences are believed to be responsible for host range variations. PMID:25002431

Milk-derived angiotensin-I-converting enzymeinhibitory peptides generated by Lactobacillus delbrueckii subsp. lactis CRL 581

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Villegas Josefina M.

2014-01-01

Full Text Available Several strains of Lactobacillus helveticus and Lactobacillus delbrueckii subsp. lactis were evaluated for their ability to release angiotensin-I-converting enzyme (ACE inhibitory peptides from α-casein (α-CN and β-casein (β-CN. Casein peptides resulting from L. delbrueckii subsp. lactis CRL 581-mediated hydrolysis exhibited the highest ACE-inhibitory (ACEI activities, with values of 53 and 40% for α-CN and β-CN, respectively. The casein hydrolysates were fractionated by reversedphase high pressure liquid chromatography and some of the active peptides were identified by mass spectrometry. The fraction with the highest ACEI activity arose from β-CN and contained a mixture of the β-CN f194-206 (QEPVLGPVRGPFP and f198-206 (LGPVRGPFP peptides. Furthermore, the ACEI tripeptide IPP was identified in all β-CN hydrolysates; L. delbrueckii subsp. lactis CRL 581 produced the highest amount of this peptide. The bioactive peptides released by CRL 581 strain may be used in the formulation of functional foods and nutraceuticals, representing a healthier and natural alternative for regulating blood pressure.

In vitro anti-bacterial and anti-adherence effects of Lactobacillus delbrueckii subsp bulgaricus on Escherichia coli.

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Abedi, D; Feizizadeh, S; Akbari, V; Jafarian-Dehkordi, A

2013-10-01

Considering the emergence of antibiotic resistance, scientists are interested in using new antimicrobial agents in the treatment of infectious diseases including infections of the enteric systems. Lactic acid bacteria have the great potential to produce antimicrobial compounds that inhibit and control pathogenic bacteria. The aim of this study was to determine the anti-bacterial and anti-adherence properties of Lactobacillus delbrueckii subsp bulgaricus against Escherichia coli. The antibacterial activity of L. delbrueckii was investigated using disc diffusion and spot on lawn methods. In vitro anti-adhesion effect of L. delbrueckii against E. coli was examined using Caco-2 cells. In anti-adhesion assay, three competition conditions including competitive inhibition, adhesion inhibition, and displacement were examined. In spot on lawn method the zone of growth inhibition of E. coli by L. delbrueckii was 21.1 mm. The cell free supernatant of L. delbrueckii showed a good antibacterial activity against E. coli which was mainly related to lactic acid produced by L. delbrueckii. When two bacteria added simultaneously (competitive inhibition) degree of inhibition of E. coli binding by L. delbrueckii was 77%. In adhesion inhibition assay, L. delbrueckii was able to exclude E. coli adherence by around 43.5%. Displacement assay showed that L. delbrueckii had strong displacement ability toward E. coli and reduction of E. coli attachment by bound L. delbrueckii was 81.3%. The results suggest that L. delbrueckii may be able to inhibit E. coli infection in the gut; however more studies including in vivo studies need to be performed.

Molecular characterization of three Lactobacillus delbrueckii subsp. bulgaricus phages.

Science.gov (United States)

Casey, Eoghan; Mahony, Jennifer; O'Connell-Motherway, Mary; Bottacini, Francesca; Cornelissen, Anneleen; Neve, Horst; Heller, Knut J; Noben, Jean-Paul; Dal Bello, Fabio; van Sinderen, Douwe

2014-09-01

In this study, three phages infecting Lactobacillus delbrueckii subsp. bulgaricus, named Ld3, Ld17, and Ld25A, were isolated from whey samples obtained from various industrial fermentations. These phages were further characterized in a multifaceted approach: (i) biological and physical characterization through host range analysis and electron microscopy; (ii) genetic assessment through genome analysis; (iii) mass spectrometry analysis of the structural components of the phages; and (iv), for one phage, transcriptional analysis by Northern hybridization, reverse transcription-PCR, and primer extension. The three obtained phage genomes display high levels of sequence identity to each other and to genomes of the so-called group b L. delbrueckii phages c5, LL-Ku, and phiLdb, where some of the observed differences are believed to be responsible for host range variations. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Draft Genome Sequence of Lactobacillus delbrueckii subsp. bulgaricus LBB.B5

NARCIS (Netherlands)

Urshev, Z.; Hajo, K.; Lenoci, L.; Bron, P.A.; Dijkstra, A.; Alkema, W.; Wels, M.; Siezen, R.J.; Minkova, S.; Hijum, S.A. van

2016-01-01

Lactobacillus delbrueckii subsp. bulgaricus LBB.B5 originates from homemade Bulgarian yogurt and was selected for its ability to form a strong association with Streptococcus thermophilus The genome sequence will facilitate elucidating the genetic background behind the contribution of LBB.B5 to the

H(+) -ATPase-defective variants of Lactobacillus delbrueckii subsp. bulgaricus contribute to inhibition of postacidification of yogurt during chilled storage.

Science.gov (United States)

Wang, Xinhui; Ren, Hongyang; Liu, Dayu; Wang, Bing; Zhu, Wenyou; Wang, Wei

2013-02-01

Continued acid production by Lactobacillus delbrueckii subsp. bulgaricus during the chilled storage of yogurt is the major cause of postacidification, resulting in a short shelf life. Two H(+) -ATPase defective variants of L. delbrueckii subsp. bulgaricus were successfully isolated and their H(+) -ATPase activities were reduced by 51.3% and 34.3%, respectively. It was shown that growth and acid production of variants were remarkably inhibited. The variants were more sensitive to acidic condition and had a significant rate for inactivation of H(+) -ATPase by N, N-dicyclohexylcarbodiimide (DCCD), along with a low H(+) -extrusion, suggesting that H(+) -ATPase is direct response for H(+) -extrusion. In addition, the variants were also more sensitive to NaCl, while H(+) -ATPase activities of variants and parent strain were significantly enhanced by NaCl stress. Obviously, H(+) -ATPase might be involved in Na(+) transportation. Furthermore, variants were inoculated in fermented milk to ferment yogurt. There was no significant difference in flavor, whereas the postacidification of yogurt during chilled storage was remarkably inhibited. It is suggested that application of L. delbrueckii subsp. bulgaricus with reduced H(+) -ATPase activity in yogurt fermentation is one of effect, economic and simple avenues of inhibiting postacidification of yogurt during refrigerated storage, giving a longer shelf life. During yogurt fermentation, continued acid production by Lactobacillus delbrueckii subsp. bulgaricus during the chilled storage of yogurt leads to milk fermentation with high postacidification, resulting in a short shelf life. In this work, 2 acid-sensitive variant strains of L. delbrueckii subsp. bulgaricus were isolated. The characteristics related to H(+) -ATPase were compared and it was observed that milk fermented by the variants had lower postacidification, giving a longer shelf life. Application of L. delbrueckii subsp. bulgaricus with reduced H(+) -ATPase activity

Profiles of Volatile Flavor Compounds in Milk Fermented with Different Proportional Combinations of Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus.

Science.gov (United States)

Dan, Tong; Wang, Dan; Wu, Shimei; Jin, Rulin; Ren, Weiyi; Sun, Tiansong

2017-09-29

Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus are key factors in the fermentation process and the final quality of dairy products worldwide. This study was performed to investigate the effects of the proportions of Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus isolated from traditionally fermented dairy products in China and Mongolia on the profile of volatile compounds produced in samples. Six proportional combinations (1:1, 1:10, 1:50, 1:100, 1:1000, and 1:10,000) of L. delbrueckii subsp. bulgaricus IMAU20401 to S. thermophilus ND03 were considered, and the volatiles were identified and quantified by solid-phase microextraction and gas chromatography-mass spectrometry (SPME-GC-MS) against an internal standard. In total, 89 volatile flavor compounds, consisting of aldehydes, ketones, acids, alcohols, esters, and aromatic hydrocarbons, were identified. Among these, some key flavor volatile compounds were identified, including acetaldehyde, 3-methylbutanal, acetoin, 2-heptanone, acetic acid, butanoic acid, and 3-methyl-1-butanol. The of L. delbrueckii subsp. bulgaricus IMAU20401 to S. thermophilus ND03 influenced the type and concentration of volatiles produced. In particular, aldehydes and ketones were present at higher concentrations in the 1:1000 treatment combination than in the other combinations. Our findings emphasize the importance of selecting the appropriate proportions of L. delbrueckii subsp. bulgaricus and S. thermophilus for the starter culture in determining the final profile of volatiles and the overall flavor of dairy products.

Profiles of Volatile Flavor Compounds in Milk Fermented with Different Proportional Combinations of Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus

Directory of Open Access Journals (Sweden)

Tong Dan

2017-09-01

Full Text Available Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus are key factors in the fermentation process and the final quality of dairy products worldwide. This study was performed to investigate the effects of the proportions of Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus isolated from traditionally fermented dairy products in China and Mongolia on the profile of volatile compounds produced in samples. Six proportional combinations (1:1, 1:10, 1:50, 1:100, 1:1000, and 1:10,000 of L. delbrueckii subsp. bulgaricus IMAU20401 to S. thermophilus ND03 were considered, and the volatiles were identified and quantified by solid-phase microextraction and gas chromatography–mass spectrometry (SPME-GC-MS against an internal standard. In total, 89 volatile flavor compounds, consisting of aldehydes, ketones, acids, alcohols, esters, and aromatic hydrocarbons, were identified. Among these, some key flavor volatile compounds were identified, including acetaldehyde, 3-methylbutanal, acetoin, 2-heptanone, acetic acid, butanoic acid, and 3-methyl-1-butanol. The of L. delbrueckii subsp. bulgaricus IMAU20401 to S. thermophilus ND03 influenced the type and concentration of volatiles produced. In particular, aldehydes and ketones were present at higher concentrations in the 1:1000 treatment combination than in the other combinations. Our findings emphasize the importance of selecting the appropriate proportions of L. delbrueckii subsp. bulgaricus and S. thermophilus for the starter culture in determining the final profile of volatiles and the overall flavor of dairy products.

Inside the adaptation process of Lactobacillus delbrueckii subsp. lactis to bile.

Science.gov (United States)

Burns, Patricia; Sánchez, Borja; Vinderola, Gabriel; Ruas-Madiedo, Patricia; Ruiz, Lorena; Margolles, Abelardo; Reinheimer, Jorge; de los Reyes-Gavilán, Clara G

2010-08-15

Progressive adaptation to bile might render some lactobacilli able to withstand physiological bile salt concentrations. In this work, the adaptation to bile was evaluated on previously isolated dairy strains of Lactobacillus delbrueckii subsp. lactis 200 and L. delbrueckii subsp. lactis 200+, a strain derived thereof with stable bile-resistant phenotype. The adaptation to bile was obtained by comparing cytosolic proteomes of both strains grown in the presence or absence of bile. Proteomics were complemented with physiological studies on both strains focusing on glycolytic end-products, the ability to adhere to the human intestinal epithelial cell line HT29-MTX and survival to simulated gastrointestinal conditions. Protein pattern comparison of strains grown with and without bile allowed us to identify 9 different proteins whose production was regulated by bile in both strains, and 17 proteins that showed differences in their levels between the parental and the bile-resistant derivative. These included general stress response chaperones, proteins involved in transcription and translation, in peptidoglycan/exopolysaccharide biosynthesis, in the lipid and nucleotide metabolism and several glycolytic and pyruvate catabolism enzymes. Differences in the level of metabolic end-products of the sugar catabolism were found between the strains 200 and 200+. A decrease in the adhesion of both strains to the intestinal cell line was detected in the presence of bile. In simulated gastric and intestinal juices, a protective effect was exerted by milk improving the survival of both microorganisms. These results indicate that bile tolerance in L. delbrueckii subsp. lactis involves several mechanisms responding to the deleterious impact of bile salts on bacterial physiology. Copyright 2010 Elsevier B.V. All rights reserved.

Molecular Characterization of Three Lactobacillus delbrueckii subsp. bulgaricus Phages

OpenAIRE

Casey, Eoghan; Mahony, Jennifer; O'Connell-Motherway, Mary; Bottacini, Francesca; Cornelissen, Anneleen; Neve, Horst; Heller, Knut J.; Noben, Jean-Paul; Dal Bello, Fabio; van Sinderen, Douwe

2014-01-01

In this study, three phages infecting Lactobacillus delbrueckii subsp. bulgaricus, named Ld3, Ld17, and Ld25A, were isolated from whey samples obtained from various industrial fermentations. These phages were further characterized in a multifaceted approach: (i) biological and physical characterization through host range analysis and electron microscopy; (ii) genetic assessment through genome analysis; (iii) mass spectrometry analysis of the structural components of the phages; and (iv), for ...

Effect of the addition of Lactobacillus delbrueckii subsp. delbrueckii on the gut microbiota composition and contribution to the well-being of European sea bass (Dicentrarchus labrax, L.)

OpenAIRE

Silvi, Stefania; Nardi, Miria; Sulpizio, Roberto; Orpianesi, Carla; Caggiano, Massimo; Carnevali, Oliana; Cresci, Alberto

2011-01-01

The present study aimed to test the effects of probiotic treatment on gut microbiota and the contribution to the well-being of European sea bass (Dicentrarchus labrax, L.). A bacterial strain of Lactobacillus delbrueckii subsp. delbrueckii (AS13B), isolated from adult European sea bass gut, was administered during sea bass development using Brachionus plicatilis and/or Artemia salina as carriers. The effective strain colonization and modulation of the gut microbiota, the mortality and the cor...

Co-culturing of Lactobacillus paracasei subsp. paracasei with a Lactobacillus delbrueckii subsp. delbrueckii mutant to make high cell density for increased lactate productivity from cassava bagasse hydrolysate.

Science.gov (United States)

John, Rojan Pappy; Nampoothiri, K Madhavan

2011-03-01

To increase the productivity of lactic acid, a co-culture of lactobacilli was made by mixing 1:1 ratio of Lactobacillus paracasei subsp. paracasei and a fast growing L. delbrueckii subsp. delbrueckii mutant. The culture was embedded on to polyurethane foam (PUF) cubes as a biofilm and used for fermentation. In order to prevent the cell leakage, the PUF cubes were further entrapped in calcium cross-linked alginate. The maximum lactic acid production using a high cell density free culture was >38 g l(-1) from ~40 g l(-1) of reducing sugar within 12 h of fermentation. Using PUF biofilms, the same yield of lactic acid attained after 24 h. When the cubes were further coated with alginate it took 36 h for the maximum yield. Even though, the productivity is slightly lesser with the alginate coating, cell leakage was decreased and cubes were reused without much decrease in production in repeated batches. Using a conventional control inoculum (3%, w/v), it took 120 h to yield same amount of lactic acid.

Increased Production of Hydrogen Peroxide by Lactobacillus delbrueckii subsp. bulgaricus upon Aeration: Involvement of an NADH Oxidase in Oxidative Stress

Science.gov (United States)

Marty-Teysset, C.; de la Torre, F.; Garel, J.-R.

2000-01-01

The growth of Lactobacillus delbrueckii subsp. bulgaricus (L. delbrueckii subsp. bulgaricus) on lactose was altered upon aerating the cultures by agitation. Aeration caused the bacteria to enter early into stationary phase, thus reducing markedly the biomass production but without modifying the maximum growth rate. The early entry into stationary phase of aerated cultures was probably related to the accumulation of hydrogen peroxide in the medium. Indeed, the concentration of hydrogen peroxide in aerated cultures was two to three times higher than in unaerated ones. Also, a similar shift from exponential to stationary phase could be induced in unaerated cultures by adding increasing concentrations of hydrogen peroxide. A significant fraction of the hydrogen peroxide produced by L. delbrueckii subsp. bulgaricus originated from the reduction of molecular oxygen by NADH catalyzed by an NADH:H2O2 oxidase. The specific activity of this NADH oxidase was the same in aerated and unaerated cultures, suggesting that the amount of this enzyme was not directly regulated by oxygen. Aeration did not change the homolactic character of lactose fermentation by L. delbrueckii subsp. bulgaricus and most of the NADH was reoxidized by lactate dehydrogenase with pyruvate. This indicated that NADH oxidase had no (or a very small) energetic role and could be involved in eliminating oxygen. PMID:10618234

Draft Genome Sequence of Lactobacillus delbrueckii subsp. bulgaricus LBB.B5.

Science.gov (United States)

Urshev, Zoltan; Hajo, Karima; Lenoci, Leonardo; Bron, Peter A; Dijkstra, Annereinou; Alkema, Wynand; Wels, Michiel; Siezen, Roland J; Minkova, Svetlana; van Hijum, Sacha A F T

2016-10-06

Lactobacillus delbrueckii subsp. bulgaricus LBB.B5 originates from homemade Bulgarian yogurt and was selected for its ability to form a strong association with Streptococcus thermophilus The genome sequence will facilitate elucidating the genetic background behind the contribution of LBB.B5 to the taste and aroma of yogurt and its exceptional protocooperation with S. thermophilus. Copyright © 2016 Urshev et al.

Genome Sequence of the Cheese-Starter Strain Lactobacillus delbrueckii subsp. lactis CRL 581.

Science.gov (United States)

Hebert, Elvira María; Raya, Raúl R; Brown, Lucía; Font de Valdez, Graciela; Savoy de Giori, Graciela; Taranto, María Pía

2013-08-08

We report the genome sequence of Lactobacillus delbrueckii subsp. lactis CRL 581 (1,911,137 bp, GC 49.7%), a proteolytic strain isolated from a homemade Argentinian hard cheese which has a key role in bacterial nutrition and releases bioactive health-beneficial peptides from milk proteins.

Two-Dimensional Electrophoresis Study of Lactobacillus delbrueckii subsp. bulgaricus Thermotolerance

OpenAIRE

Gouesbet, Gwenola; Jan, Gwenael; Boyaval, Patrick

2002-01-01

The response of Lactobacillus delbrueckii subsp. bulgaricus cells to heat stress was studied by use of a chemically defined medium. Two-dimensional electrophoresis (2-DE) analysis was used to correlate the kinetics of heat shock protein (HSP) induction with cell recovery from heat injury. We demonstrated that enhanced viability, observed after 10 min at 65°C, resulted from the overexpression of HSP and from mechanisms not linked to protein synthesis. In order to analyze the thermoadaptation m...

Production of lactic acid from whey using Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus

Directory of Open Access Journals (Sweden)

Adriana M. Rojas

2015-09-01

Full Text Available The main objective of this research was to determine the proper growth conditions of Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus for the production of lactic acid using serum as substract. This serum was obtain from the department of Cesar, Colombia. Lactic acid is the result of the extraction and purification of fermentation broths in which bacteria Lactobacillus delbrueckii subsp bulgaricus and Streptococcus thermophilus are used, which are usually used for the production of yogurt. The substrate was supplemented with yeast extract, ammonium phosphate as a nitrogen source, and calcium carbonate as a neutralizer, in order to optimize the consumption, by the bacteria, of the main carbohydrate present in serum (lactose. During the fermentation (up to 72 h the inoculums concentration, and temperature were controlled. Purification consisted in esterification, filtration of solids formed during the reaction, and removing of water by evaporation and nitrogen influx. Finally, lactic acid was obtained with 78,0% purity (36.7 g/L, which was characterized by infrared spectroscopy

Oral supplementation with Lactobacillus delbrueckii subsp. bulgaricus 8481 enhances systemic immunity in elderly subjects.

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Moro-García, Marco Antonio; Alonso-Arias, Rebeca; Baltadjieva, Maria; Fernández Benítez, Carlos; Fernández Barrial, Manuel Amadeo; Díaz Ruisánchez, Enrique; Alonso Santos, Ricardo; Alvarez Sánchez, Magdalena; Saavedra Miján, Juan; López-Larrea, Carlos

2013-08-01

Throughout life, there is an aging of the immune system that causes impairment of its defense capability. Prevention or delay of this deterioration is considered crucial to maintain general health and increase longevity. We evaluated whether dietary supplementation with Lactobacillus delbrueckii subsp. bulgaricus 8481 could enhance the immune response in the elderly. This multi-center, double-blind, and placebo controlled study enrolled 61 elderly volunteers who were randomly assigned to receive either placebo or probiotics. Each capsule of probiotics contained at least 3 × 10(7)  L. delbrueckii subsp. bulgaricus 8481. Individuals in the study were administered three capsules per day for 6 months. Blood samples were obtained at baseline (time 0), end of month 3, and month 6. We characterized cell subpopulations, measured cytokines by flow cytometry, quantified T cell receptor excision circle (TREC) by real-time PCR (RT-PCR), and determined human β-defensin-2 (hBD-2) concentrations and human cytomegalovirus (CMV) titers by enzyme-linked immunosorbent assay (ELISA). Elderly responded to the intake of probiotic with an increase in the percentage of NK cells, an improvement in the parameters defining the immune risk profile (IRP), and an increase in the T cell subsets that are less differentiated. The probiotic group also showed decreased concentrations of the pro-inflammatory cytokine IL-8 but increased antimicrobial peptide hBD-2. These effects disappeared within 6 months of stopping the probiotic intake. Immunomodulation induced by L. delbrueckii subsp. bulgaricus 8481 could favor the maintenance of an adequate immune response, mainly by slowing the aging of the T cell subpopulations and increasing the number of immature T cells which are potential responders to new antigens.

Introduction of peptidase genes from Lactobacillus delbrueckii subsp. lactis into Lactococcus lactis and controlled expression

NARCIS (Netherlands)

Wegmann, U.; Klein, J.R.; Drumm, I.; Kuipers, O.P.; Henrich, B.

Peptidases PepI, PepL, PepW, and PepG from Lactobacillus delbrueckii subsp, lactis, which have no counterparts in Lactococcus lactis, and peptidase PepQ were examined to determine their potential to confer new peptidolytic properties to lactococci, Controllable expression of the corresponding genes

Influence of ions on growth and production of exopolysaccharides by Lactobacillus delbrueckii subsp. bulgaricus NCFB 2772

NARCIS (Netherlands)

Grobben, G.J.; Boels, I.C.; Sikkema, J.; Smith, M.R.; Bont, de J.A.M.

2000-01-01

Several lactic acid bacteria produce exopolysaccharides (EPS), either attached to the cell wall or excreted into the environment as slime material. EPS produced by Lactobacillus delbrueckii subsp. bulgaricus (Lb. bulgaricus) and Streptococcus thermophilus play an important role in improving the

A novel chimeric prophage vB_LdeS-phiJB from commercial Lactobacillus delbrueckii subsp. bulgaricus.

Science.gov (United States)

Guo, Tingting; Zhang, Chenchen; Xin, Yongping; Xin, Min; Kong, Jian

2016-05-01

Prophage vB_LdeS-phiJB (phiJB) was induced by mitomycin C and UV radiation from the Lactobacillus delbrueckii subsp. bulgaricus SDMCC050201 isolated from a Chinese yoghurt sample. It has an isometric head and a non-contractile tail with 36,969 bp linear double-stranded DNA genome, which is classified into the group a of Lb. delbrueckii phages. The genome of phiJB is highly modular with functionally related genes clustered together. Unexpectedly, there is no similarity of its DNA replication module to any phages that have been reported, while it consists of open-reading frames homologous to the proteins of Lactobacillus strains. Comparative genomic analysis indicated that its late gene clusters, integration/lysogeny modules and DNA replication module derived from different evolutionary ancestors and integrated into a chimera. Our results revealed a novel chimeric phage of commercial Lb. delbrueckii and will broaden the knowledge of phage diversity in the dairy industry.

Cell-Wall-Bound Proteinase of Lactobacillus delbrueckii subsp. lactis ACA-DC 178: Characterization and Specificity for β-Casein

Science.gov (United States)

Tsakalidou, E.; Anastasiou, R.; Vandenberghe, I.; van Beeumen, J.; Kalantzopoulos, G.

1999-01-01

Lactobacillus delbrueckii subsp. lactis ACA-DC 178, which was isolated from Greek Kasseri cheese, produces a cell-wall-bound proteinase. The proteinase was removed from the cell envelope by washing the cells with a Ca2+-free buffer. The crude proteinase extract shows its highest activity at pH 6.0 and 40°C. It is inhibited by phenylmethylsulfonyl fluoride, showing that the enzyme is a serine-type proteinase. Considering the substrate specificity, the enzyme is similar to the lactococcal PI-type proteinases, since it hydrolyzes β-casein mainly and α- and κ-caseins to a much lesser extent. The cell-wall-bound proteinase from L. delbrueckii subsp. lactis ACA-DC 178 liberates four main peptides from β-casein, which have been identified. PMID:10223997

Lactobacillus delbrueckii subsp lactis CIDCA 133 modulates response of human epithelial and dendritic cells infected with Bacillus cereus.

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Rolny, I S; Tiscornia, I; Racedo, S M; Pérez, P F; Bollati-Fogolín, M

2016-11-30

It is known that probiotic microorganisms are able to modulate pathogen virulence. This ability is strain dependent and involves multiple interactions between microorganisms and relevant host's cell populations. In the present work we focus on the effect of a potentially probiotic lactobacillus strain (Lactobacillus delbrueckii subsp. lactis CIDCA 133) in an in vitro model of Bacillus cereus infection. Our results showed that infection of intestinal epithelial HT-29 cells by B. cereus induces nuclear factor kappa B (NF-κB) pathway. Noteworthy, the presence of strain L. delbrueckii subsp.lactis CIDCA 133 increases stimulation. However, B. cereus-induced interleukin (IL)-8 production by epithelial cells is partially abrogated by L. delbrueckii subsp. lactis CIDCA 133. These findings suggest that signalling pathways other than that of NF-κB are involved. In a co-culture system (HT-29 and monocyte-derived dendritic cells), B. cereus was able to translocate from the epithelial (upper) to the dendritic cell compartment (lower). This translocation was partially abrogated by the presence of lactobacilli in the upper compartment. In addition, infection of epithelial cells in the co-culture model, led to an increase in the expression of CD86 by dendritic cells. This effect could not be modified in the presence of lactobacilli. Interestingly, infection of enterocytes with B. cereus triggers production of proinflammatory cytokines by dendritic cells (IL-8, IL-6 and tumour necrosis factor alpha (TNF-α)). The production of TNF-α (a protective cytokine in B. cereus infections) by dendritic cells was increased in the presence of lactobacilli. The present work demonstrates for the first time the effect of L. delbrueckii subsp. lactis CIDCA 133, a potentially probiotic strain, in an in vitro model of B. cereus infection. The presence of the probiotic strain modulates cell response both in infected epithelial and dendritic cells thus suggesting a possible beneficial effect of

Characterization of Lipoteichoic Acids as Lactobacillus delbrueckii Phage Receptor Components

OpenAIRE

Räisänen, Liisa; Schubert, Karin; Jaakonsaari, Tiina; Alatossava, Tapani

2004-01-01

Lipoteichoic acids (LTAs) were purified from Lactobacillus delbrueckii subsp. lactis ATCC 15808 and its LL-H adsorption-resistant mutant, Ads-5, by hydrophobic interaction chromatography. L. delbrueckii phages (LL-H, the LL-H host range mutant, and JCL1032) were inactivated by these poly(glycerophosphate) type of LTAs in vitro in accordance to their adsorption to intact ATCC 15808 and Ads-5 cells.

Transcriptome-Based Characterization of Interactions between Saccharomyces cerevisiae and Lactobacillus delbrueckii subsp. bulgaricus in Lactose-Grown Chemostat Cocultures

NARCIS (Netherlands)

Mendes, F.; Sieuwerts, S.; De Hulster, E.; Almering, M.J.; Luttik, M.A.; Pronk, J.T.; Smid, E.J.; Bron, P.A.; Daran-Lapujade, P.

2013-01-01

Mixed populations of Saccharomyces cerevisiae yeasts and lactic acid bacteria occur in many dairy, food, and beverage fermentations, but knowledge about their interactions is incomplete. In the present study, interactions between Saccharomyces cerevisiae and Lactobacillus delbrueckii subsp.

Transcriptome-based characterization of interactions between Saccharomyces cerevisiae and Lactobacillus delbrueckii subsp. bulgaricus in lactose-grown chemostat cocultures

NARCIS (Netherlands)

Mendes, F.; Sieuwerts, S.; Hulster, de E.; Almering, M.J.; Luttik, M.A.H.; Pronk, J.T.; Smid, E.J.; Baron, P.A.; Daran-Lapujade, P.

2013-01-01

Mixed populations of Saccharomyces cerevisiae yeasts and lactic acid bacteria occur in many dairy, food, and beverage fermentations, but knowledge about their interactions is incomplete. In the present study, interactions between Saccharomyces cerevisiae and Lactobacillus delbrueckii subsp.

Enhancing the Sweetness of Yoghurt through Metabolic Remodeling of Carbohydrate Metabolism in Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus.

Science.gov (United States)

Sørensen, Kim I; Curic-Bawden, Mirjana; Junge, Mette P; Janzen, Thomas; Johansen, Eric

2016-06-15

Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus are used in the fermentation of milk to produce yoghurt. These species normally metabolize only the glucose moiety of lactose, secreting galactose and producing lactic acid as the main metabolic end product. We used multiple serial selection steps to isolate spontaneous mutants of industrial strains of S. thermophilus and L. delbrueckii subsp. bulgaricus that secreted glucose rather than galactose when utilizing lactose as a carbon source. Sequencing revealed that the S. thermophilus strains had mutations in the galKTEM promoter, the glucokinase gene, and genes encoding elements of the glucose/mannose phosphotransferase system (PTS). These strains metabolize galactose but are unable to phosphorylate glucose internally or via the PTS. The L. delbrueckii subsp. bulgaricus mutants had mutations in genes of the glucose/mannose PTS and in the pyruvate kinase gene. These strains cannot grow on exogenous glucose but are proficient at metabolizing internal glucose released from lactose by β-galactosidase. The resulting strains can be combined to ferment milk, producing yoghurt with no detectable lactose, moderate levels of galactose, and high levels of glucose. Since glucose tastes considerably sweeter than either lactose or galactose, the sweetness of the yoghurt is perceptibly enhanced. These strains were produced without the use of recombinant DNA technology and can be used for the industrial production of yoghurt with enhanced intrinsic sweetness and low residual levels of lactose. Based on a good understanding of the physiology of the lactic acid bacteria Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus, we were able, by selecting spontaneously occurring mutants, to change dramatically the metabolic products secreted into the growth medium. These mutants consume substantially more of the lactose, metabolize some of the galactose, and secrete the remaining galactose

Characterization of Lipoteichoic Acids as Lactobacillus delbrueckii Phage Receptor Components

Science.gov (United States)

Räisänen, Liisa; Schubert, Karin; Jaakonsaari, Tiina; Alatossava, Tapani

2004-01-01

Lipoteichoic acids (LTAs) were purified from Lactobacillus delbrueckii subsp. lactis ATCC 15808 and its LL-H adsorption-resistant mutant, Ads-5, by hydrophobic interaction chromatography. L. delbrueckii phages (LL-H, the LL-H host range mutant, and JCL1032) were inactivated by these poly(glycerophosphate) type of LTAs in vitro in accordance to their adsorption to intact ATCC 15808 and Ads-5 cells. PMID:15292157

Produksi Asam Laktat oleh Lactobacillus delbrueckii subsp. bulgaricus dengan Sumber Karbon Tetes Tebu

Directory of Open Access Journals (Sweden)

Laita Nurjannah

2017-04-01

Full Text Available Senyawa asam laktat sangat dibutuhkan di dunia industri. Namun produksi dengan menggunakan mikrob masih menggunakan bahan pangan sebagai substratnya. Alternatif substrat untuk produksi asam laktat  sebagai pengganti penggunaan bahan pangan  sangat diperlukan industri. Tetes tebu merupakan salah satu substrat yang kaya akan sumber  karbon yang dapat digunakan sebagai komponen media pertumbuhan bakteri. Ketersediaannya melimpah dan harganya murah. Tujuan penelitian ini adalah tetes tebu dapat digunakan sebagai alternatif  sumber karbon bakteri Lactobacillus delbrueckii subsp. bulgaricus untuk menghasilkan asam laktat. Langkah penelitian ini meliputi hidrolisis dan detoksifikasi tetes tebu, uji kualitatif gula pereduksi tetes tebu, analisis gula total dengan metode fenol sulfat, penentuan kurva pertumbuhan bakteri, produksi dan ekstraksi asam laktat, serta analisis kualitatif asam laktat dengan menggunakan kromatografi cair kinerja tinggi. Hasil penelitian menunjukkan bahwa tetes tebu dapat digunakan sebagai alternatif sumber karbon. Hal ini terbukti bakteri dapat tumbuh dengan baik ketika media diberi 0.5% tetes tebu. Konsentrasi gula total tetes tebu adalah 1090 g/L. Uji gula pereduksi menunjukkan hasil yang positif untuk uji Selliwanof, uji Benedict, dan uji Barfoed. Pertumbuhan optimum L. delbrueckii subsp. bulgaricus terjadi pada suhu 42°C dengan agitasi 150 rpm. Produksi asam laktat dilakukan selama 24 jam. Kadar asam laktat yang dihasilkan sebesar 2.80% dengan biomassa sel kering sebesar 0.002 g/L dan pH media fermentasi sebesar 4.0. Hasil analisis kualitatif kromatografi cair kinerja tinggi juga menunjukkan bahwa produk dari hasil fermentasi adalah asam laktat. Abstract. Lactic acid is needed as an industrial feed. However, by using a microbial production still uses food material as a substrate. Alternative substrates for the production of lactic acid is needed in industry. Molasses are potential substrates due to the richness in

Novel phage group infecting Lactobacillus delbrueckii subsp. lactis, as revealed by genomic and proteomic analysis of bacteriophage Ldl1.

Science.gov (United States)

Casey, Eoghan; Mahony, Jennifer; Neve, Horst; Noben, Jean-Paul; Dal Bello, Fabio; van Sinderen, Douwe

2015-02-01

Ldl1 is a virulent phage infecting the dairy starter Lactobacillus delbrueckii subsp. lactis LdlS. Electron microscopy analysis revealed that this phage exhibits a large head and a long tail and bears little resemblance to other characterized phages infecting Lactobacillus delbrueckii. In vitro propagation of this phage revealed a latent period of 30 to 40 min and a burst size of 59.9 +/- 1.9 phage particles. Comparative genomic and proteomic analyses showed remarkable similarity between the genome of Ldl1 and that of Lactobacillus plantarum phage ATCC 8014-B2. The genomic and proteomic characteristics of Ldl1 demonstrate that this phage does not belong to any of the four previously recognized L. delbrueckii phage groups, necessitating the creation of a new group, called group e, thus adding to the knowledge on the diversity of phages targeting strains of this industrially important lactic acid bacterial species.

Screening in a Lactobacillus delbrueckii subsp. bulgaricus collection to select a strain able to survive to the human intestinal tract.

Science.gov (United States)

Vázquez, Clotilde; Botella-Carretero, José I; García-Albiach, Raimundo; Pozuelo, María J; Rodríguez-Baños, Mercedes; Baquero, Fernando; Baltadjieva, María A; del Campo, Rosa

2013-01-01

Genetic diversity and resistance of Lactobacillus bulgaricus sbsp. delbrueckii collection with 100 isolates from different home-made yogurt in rural Bulgarian areas were determined. The strain K98 was the most resistant to bile salts and low pH. Survival and effects on short chain fatty acids production were tested in 20 healthy volunteers. High genetic diversity was observed in the L. bulgaricus collection by RAPD, whereas the ability of tolerate high deoxycholic acid concentrations, and different acid pHs was variable. The strain K98 was selected and used to prepare a homemade yogurt which was administered to 20 healthy volunteers (500 ml/day during 15d). A basal faecal sample and another after yogurt intake were recovered. DGGE experiments, using both universal and Lactic Acid Bacteria (LAB) primers, demonstrated no significant changes in the qualitative composition of gut microbiota. A band corresponding to L. bulgaricus was observed in all 20 samples. Viable L. bulgaricus K98 strain was only recovered in one volunteer. After yogurt intake we found an increase of LAB and Clostridium perfringens, and a decrease of Bacteroides- Prevotella-Porphyromonas. In addition, increases of acetic, butyric and 2-hydroxy-butyric acids in faeces were detected. Genetic diversity of L. delbrueckii subsp. bulgaricus especie is high We have isolated a probiotic resistant strain to bile and high acidity, L. delbrueckii subsp. bulgaricus-K98. Qualitative and quantitative changes in the intestinal microbiota are found after ingestion of a homemade yogurt containing this strain, with a concomitant increase in faecal SCFA. Our findings support the interest in developing further studies providing different amounts of L. delbrueckii subsp. bulgaricus-K98, and should evaluate its clinical effects in human disease. Copyright © AULA MEDICA EDICIONES 2013. Published by AULA MEDICA. All rights reserved.

Genome Sequence of Lactobacillus delbrueckii subsp. lactis CNRZ327, a Dairy Bacterium with Anti-Inflammatory Properties.

Science.gov (United States)

El Kafsi, Hela; Binesse, Johan; Loux, Valentin; Buratti, Julien; Boudebbouze, Samira; Dervyn, Rozenn; Hammani, Amal; Maguin, Emmanuelle; van de Guchte, Maarten

2014-07-17

Lactobacillus delbrueckii subsp. lactis CNRZ327 is a dairy bacterium with anti-inflammatory properties both in vitro and in vivo. Here, we report the genome sequence of this bacterium, which appears to contain no less than 215 insertion sequence (IS) elements, an exceptionally high number regarding the small genome size of the strain. Copyright © 2014 El Kafsi et al.

Optimization of Exopolysaccharide Production by Lactobacillus delbrueckii subsp. bulgaricus RR Grown in a Semidefined Medium

Science.gov (United States)

Kimmel, Stacy A.; Roberts, Robert F.; Ziegler, Gregory R.

1998-01-01

The optimal fermentation temperature, pH, and Bacto-casitone (Difco Laboratories, Detroit, Mich.) concentration for production of exopolysaccharide by Lactobacillus delbrueckii subsp. bulgaricus RR in a semidefined medium were determined by using response surface methods. The design consisted of 20 experiments, 15 unique combinations, and five replications. All fermentations were conducted in a fermentor with a 2.5-liter working volume and were terminated when 90% of the glucose in the medium had been consumed. The population of L. delbrueckii subsp. bulgaricus RR and exopolysaccharide content were measured at the end of each fermentation. The optimum temperature, pH, and Bacto-casitone concentration for exopolysaccharide production were 38°C, 5, and 30 g/liter, respectively, with a predicted yield of 295 mg of exopolysaccharide/liter. The actual yield under these conditions was 354 mg of exopolysaccharide/liter, which was within the 95% confidence interval (217 to 374 mg of exopolysaccharide/liter). An additional experiment conducted under optimum conditions showed that exopolysaccharide production was growth associated, with a specific production at the endpoint of 101.4 mg/g of dry cells. Finally, to obtain material for further characterization, a 100-liter fermentation was conducted under optimum conditions. Twenty-nine grams of exopolysaccharide was isolated from centrifuged, ultrafiltered fermentation broth by ethanol precipitation. PMID:9464404

Lactobacillus delbrueckii subsp. lactis (strain CIDCA 133) stimulates murine macrophages infected with Citrobacter rodentium.

Science.gov (United States)

Hugo, Ayelén A; Rolny, Ivanna S; Romanin, David; Pérez, Pablo F

2017-03-01

Citrobacter rodentium is a specific murine enteropathogen which causes diarrheal disease characterized by colonic hyperplasia and intestinal inflammation. Recruitment of neutrophils and macrophages constitute a key step to control the infection. Since modulation of the activity of professional phagocytic cells could contribute to improve host´s defences against C. rodentium, we investigated the effect of Lactobacillus delbrueckii subsp. lactis (strain CIDCA 133) on the interaction between murine macrophages (RAW 264.7) and C. rodentium. Phagocytosis, surface molecules and inducible nitric oxide synthase (iNOs) expression were determined by flow cytometry. Reactive oxygen species (ROS) were assessed by fluorescence microscopy. The presence of lactobacilli increased phagocytosis of C. rodentium whereas C. rodentium had no effect on lactobacilli internalization. Survival of internalized C. rodentium diminished when strain CIDCA 133 was present. CD-86, MHCII, iNOs expression and nitrite production were increased when C. rodentium and lactobacilli were present even though strain CIDCA 133 alone had no effect. Strain CIDCA 133 led to a strong induction of ROS activity which was not modified by C. rodentium. Lactobacillus delbrueckii subsp. lactis (strain CIDCA 133) is able to increase the activation of murine macrophages infected with C. rodentium. The sole presence of lactobacilli is enough to modify some stimulation markers (e.g. ROS induction) whereas other markers require the presence of both bacteria; thus, indicating a synergistic effect.

Characterization of the mature cell surface proteinase of Lactobacillus delbrueckii subsp. lactis CRL 581.

Science.gov (United States)

Villegas, Josefina M; Brown, Lucía; Savoy de Giori, Graciela; Hebert, Elvira M

2015-05-01

The cell envelope-associated proteinase (CEP) of Lactobacillus delbrueckii subsp. lactis CRL 581 (PrtL) has an essential role in bacterial growth, contributes to the flavor and texture development of fermented products, and can release bioactive health-beneficial peptides during milk fermentation. The genome of L. delbrueckii subsp. lactis CRL 581 possesses only one gene that encodes PrtL, which consists of 1924 amino acids and is a multidomain protein anchored to the cell via its W domain. PrtL was extracted from the cell under high ionic strength conditions using NaCl, suggesting an electrostatic interaction between the proteinase and the cell envelope. The released PrtL was purified and biochemically characterized; its activity was maximal at temperatures between 37 and 40 °C and at pH between 7 and 8. Under optimal conditions, PrtL exhibited higher affinity for succinyl-alanyl-alanyl-prolyl-phenylalanine-p-nitroanilide than for succinyl-alanyl-glutamyl-prolyl-phenylalanine-p-nitroanilide, while methoxy-succinyl-arginyl-prolyl-tyrosyl-p-nitroanilide was not degraded. A similar α- and β-casein degradation pattern was observed with the purified and the cell envelope-bound proteinase. Finally, on the basis of its specificity towards caseins and the unique combination of amino acids at residues thought to be involved in substrate specificity, PrtL can be classified as a representative of a new group of CEP.

Immune Regulatory Effect of Newly Isolated Lactobacillus delbrueckii from Indian Traditional Yogurt.

Science.gov (United States)

Hong, Yi-Fan; Lee, Yoon-Doo; Park, Jae-Yeon; Jeon, Boram; Jagdish, Deepa; Jang, Soojin; Chung, Dae Kyun; Kim, Hangeun

2015-08-01

Lactic acid bacteria (LAB) are microorganisms that are believed to provide health benefits. Here, we isolated LAB from Indian fermented foods, such as traditional Yogurt and Dosa. LAB from Yogurt most significantly induced TNF-α and IL-1β production, whereas LAB from Dosa induced mild cytokine production. After 16S rRNA gene sequencing and phylogenetic analysis, a Yogurt-borne lactic acid bacterium was identified and classified as Lactobacillus delbrueckii subsp. bulgaricus, and it was renamed L. delbrueckii K552 for the further studies. Our data suggest that the newly isolated L. delbrueckii can be used for the treatment of immune deficiency disorders.

Genes involved in lactose catabolism and organic acid production during growth of Lactobacillus delbrueckii UFV H2b20 in skimmed milk.

Science.gov (United States)

Do Carmo, A P; De Oliveira, M N V; Da Silva, D F; Castro, S B; Borges, A C; De Carvalho, A F; De Moraes, C A

2012-03-01

There are three main reasons for using lactic acid bacteria (LAB) as starter cultures in industrial food fermentation processes: food preservation due to lactic acid production; flavour formation due to a range of organic molecules derived from sugar, lipid and protein catabolism; and probiotic properties attributed to some strains of LAB, mainly of lactobacilli. The aim of this study was to identify some genes involved in lactose metabolism of the probiotic Lactobacillus delbrueckii UFV H2b20, and analyse its organic acid production during growth in skimmed milk. The following genes were identified, encoding the respective enzymes: ldh - lactate dehydrogenase, adhE - Ldb1707 acetaldehyde dehydrogenase, and ccpA-pepR1 - catabolite control protein A. It was observed that L. delbrueckii UFV H2b20 cultivated in different media has the unexpected ability to catabolyse galactose, and to produce high amounts of succinic acid, which was absent in the beginning, raising doubts about the subspecies in question. The phylogenetic analyses showed that this strain can be compared physiologically to L. delbrueckii subsp. bulgaricus and L. delbrueckii subsp. lactis, which are able to degrade lactose and can grow in milk. L. delbrueckii UFV H2b20 sequences have grouped with L. delbrueckii subsp. bulgaricus ATCC 11842 and L. delbrueckii subsp. bulgaricus ATCC BAA-365, strengthening the classification of this probiotic strain in the NCFM group proposed by a previous study. Additionally, L. delbrueckii UFV H2b20 presented an evolutionary pattern closer to that of probiotic Lactobacillus acidophilus NCFM, corroborating the suggestion that this strain might be considered as a new and unusual subspecies among L. delbrueckii subspecies, the first one identified as a probiotic. In addition, its unusual ability to metabolise galactose, which was significantly consumed in the fermentation medium, might be exploited to produce low-browning probiotic Mozzarella cheeses, a desirable property

Analysis of the exopolysaccharides produced by Lactobacillus delbrueckii subsp. bulgaricus NCFB 2772 grown in continuous culture on glucose and fructose.

NARCIS (Netherlands)

Grobben, G.J.; Casteren, van W.H.M.; Schols, H.A.; Oosterveld, A.; Sala, G.; Smith, M.R.; Sikkema, J.; Bont, de J.A.M.

1997-01-01

The exopolysaccharides produced by Lactobacillus delbrueckii subsp. bulgaricus NCFB 2772 grown in defined medium were investigated. At equal cell densities, the strain produced 95 mg l−1 exopolysaccharides with glucose and 30 mg l−1 with fructose as the carbohydrate source. High-performance

A combination of direct viable count and fluorescence in situ hybridization for specific enumeration of viable Lactobacillus delbrueckii subsp.bulgaricus and Streptococcus thermophilus.

Science.gov (United States)

García-Hernández, J; Moreno, Y; Amorocho, C M; Hernández, M

2012-03-01

We have developed a direct viable count (DVC)-FISH procedure for quickly and easily discriminating between viable and nonviable cells of Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus strains, the traditional yogurt bacteria. direct viable count method has been modified and adapted for Lact. delbrueckii subsp. bulgaricus and Strep. thermophilus analysis by testing different times of incubation and concentrations of DNA-gyrase inhibitors. DVC procedure has been combined with fluorescent in situ hybridization (FISH) for the specific detection of viable cells of both bacteria with specific rRNA oligonucleotide probes (DVC-FISH). Of the four antibiotics tested (novobiocin, nalidixic acid, pipemidic acid and ciprofloxacin), novobiocin was the most effective for DVC method and the optimum incubation time was 7 h for both bacteria. The number of viable cells was obtained by the enumeration of specific hybridized cells that were elongated at least twice their original length for Lactobacillus and twice their original size for Streptococcus. This technique was successfully applied to detect viable cells in inoculated faeces. Results showed that this DVC-FISH procedure is a quick and culture-independent useful method to specifically detect viable Lact. delbrueckii subsp. bulgaricus and Strep. thermophilus in different samples, being applied for the first time to lactic acid bacteria. © 2011 The Authors. Letters in Applied Microbiology © 2011 The Society for Applied Microbiology.

Influence of different proteolytic strains of Streptococcus thermophilus in co-culture with Lactobacillus delbrueckii subsp. bulgaricus on the metabolite profile of set-yoghurt.

Science.gov (United States)

Settachaimongkon, Sarn; Nout, M J Robert; Antunes Fernandes, Elsa C; Hettinga, Kasper A; Vervoort, Jacques M; van Hooijdonk, Toon C M; Zwietering, Marcel H; Smid, Eddy J; van Valenberg, Hein J F

2014-05-02

Proto-cooperation between Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus is one of the key factors that determine the fermentation process and final quality of yoghurt. In this study, the interaction between different proteolytic strains of S. thermophilus and L. delbrueckii subsp. bulgaricus was investigated in terms of microbial growth, acidification and changes in the biochemical composition of milk during set-yoghurt fermentation. A complementary metabolomics approach was applied for global characterization of volatile and non-volatile polar metabolite profiles of yoghurt associated with proteolytic activity of the individual strains in the starter cultures. The results demonstrated that only non-proteolytic S. thermophilus (Prt-) strain performed proto-cooperation with L. delbrueckii subsp. bulgaricus. The proto-cooperation resulted in significant higher populations of the two species, faster milk acidification, significant abundance of aroma volatiles and non-volatile metabolites desirable for a good organoleptic quality of yoghurt. Headspace SPME-GC/MS and (1)H NMR resulted in the identification of 35 volatiles and 43 non-volatile polar metabolites, respectively. Furthermore, multivariate statistical analysis allows discriminating set-yoghurts fermented by different types of starter cultures according to their metabolite profiles. Our finding underlines that selection of suitable strain combinations in yoghurt starters is important for achieving the best technological performance regarding the quality of product. Copyright © 2014 Elsevier B.V. All rights reserved.

Draft Genome Sequence of Lactobacillus delbrueckii subsp. bulgaricus CFL1, a Lactic Acid Bacterium Isolated from French Handcrafted Fermented Milk

OpenAIRE

Meneghel, Julie; Dugat-Bony, Eric; Irlinger, Fran?oise; Loux, Valentin; Vidal, Marie; Passot, St?phanie; B?al, Catherine; Layec, S?verine; Fonseca, Fernanda

2016-01-01

Lactobacillus delbrueckii subsp. bulgaricus (L. bulgaricus) is a lactic acid bacterium widely used for the production of yogurt and cheeses. Here, we report the genome sequence of L. bulgaricus CFL1 to improve our knowledge on its stress-induced damages following production and end-use processes.

Comparative Sequence Analysis of Plasmids from Lactobacillus delbrueckii and Construction of a Shuttle Cloning Vector▿

Science.gov (United States)

Lee, Ju-Hoon; Halgerson, Jamie S.; Kim, Jeong-Hwan; O'Sullivan, Daniel J.

2007-01-01

While plasmids are very commonly associated with the majority of the lactic acid bacteria, they are only very rarely associated with Lactobacillus delbrueckii, with only four characterized to date. In this study, the complete sequence of a native plasmid, pDOJ1, from a strain of Lactobacillus delbrueckii subsp. bulgaricus was determined. It consisted of a circular DNA molecule of 6,220 bp with a G+C content of 44.6% and a characteristic ori and encoded six open reading frames (ORFs), of which functions could be predicted for three—a mobilization (Mob) protein, a transposase, and a fused primase-helicase replication protein. Comparative analysis of pDOJ1 and the other available L. delbrueckii plasmids (pLBB1, pJBL2, pN42, and pLL1212) revealed a very similar organization and amino acid identities between 85 and 98% for the putative proteins of all six predicted ORFs from pDOJ1, reflecting a common origin for L. delbrueckii plasmids. Analysis of the fused primase-helicase replication gene found a similar fused organization only in the theta replicating group B plasmids from Streptococcus thermophilus. This observation and the ability of the replicon to function in S. thermophilus support the idea that the origin of plasmids in L. delbrueckii was likely from S. thermophilus. This may reflect the close association of these two species in dairy fermentations, particularly yogurt production. As no vector based on plasmid replicons from L. delbrueckii has previously been constructed, an Escherichia coli-L. delbrueckii shuttle cloning vector, pDOJ4, was constructed from pDOJ1, the p15A ori, the chloramphenicol resistance gene of pCI372, and the lacZ polylinker from pUC18. This cloning vector was successfully introduced into E. coli, L. delbrueckii subsp. bulgaricus, S. thermophilus, and Lactococcus lactis. This shuttle cloning vector provides a new tool for molecular analysis of Lactobacillus delbrueckii and other lactic acid bacteria. PMID:17526779

Continuous D-lactic acid production by a novel thermotolerant Lactobacillus delbrueckii subsp. lactis QU 41.

Science.gov (United States)

Tashiro, Yukihiro; Kaneko, Wataru; Sun, Yanqi; Shibata, Keisuke; Inokuma, Kentaro; Zendo, Takeshi; Sonomoto, Kenji

2011-03-01

We isolated and characterized a D-lactic acid-producing lactic acid bacterium (D-LAB), identified as Lactobacillus delbrueckii subsp. lactis QU 41. When compared to Lactobacillus coryniformis subsp. torquens JCM 1166 (T) and L. delbrueckii subsp. lactis JCM 1248 (T), which are also known as D-LAB, the QU 41 strain exhibited a high thermotolerance and produced D-lactic acid at temperatures of 50 °C and higher. In order to optimize the culture conditions of the QU 41 strain, we examined the effects of pH control, temperature, neutralizing reagent, and initial glucose concentration on D-lactic acid production in batch cultures. It was found that the optimal production of 20.1 g/l D-lactic acid was acquired with high optical purity (>99.9% of D-lactic acid) in a pH 6.0-controlled batch culture, by adding ammonium hydroxide as a neutralizing reagent, at 43 °C in MRS medium containing 20 g/l glucose. As a result of product inhibition and low cell density, continuous cultures were investigated using a microfiltration membrane module to recycle flow-through cells in order to improve D-lactic acid productivity. At a dilution rate of 0.87 h(-1), the high cell density continuous culture exhibited the highest D-lactic acid productivity of 18.0 g/l/h with a high yield (ca. 1.0 g/g consumed glucose) and a low residual glucose (<0.1 g/l) in comparison with systems published to date.

Listeria innocua and Lactobacillus delbrueckii subsp. bulgaricus employ different strategies to cope with acid stress

DEFF Research Database (Denmark)

Shabala, Lana; McMeekin, Tom; Budde, Birgitte Bjørn

2006-01-01

'-dichlorofluorescein diacetate succinimidyl ester (CDCFDA-SE) was employed that enabled reliable measurements of intracellular pH (pHi) to a minimum pHi of 4.0. Changes in pHi and H+ fluxes from immobilised bacteria were measured using fluorescence ratio imaging microscopy (FRIM) and a non-invasive ion flux measuring...... technique (MIFE), respectively. L. innocua maintained a relatively constant pHi of 5.5-6.1 at pHex 4 and 5 via H+ extrusion. In contrast, L. delbrueckii subsp. bulgaricus progressively lowered pHi towards pHex over the entire pHex range examined. The type of acidulant used influenced pH regulation with both...... pHi and H+ -fluxes being more severely affected by LA compared to HCl. Overall, our data demonstrated different adaptive strategies in these two bacteria. While L. innocua expels protons to maintain a constant pHi, L. delbrueckii subsp. bulgaricus allows proton entry after acidic treatment so that pHi...

Three new insertion sequence elements ISLdl2, ISLdl3, and ISLdl4 in Lactobacillus delbrueckii: isolation, molecular characterization, and potential use for strain identification.

Science.gov (United States)

Ravin, Victor; Alatossava, Tapani

2003-05-01

A group of new insertion sequence (IS) elements, ISLdl2, ISLdl3, and ISLdl4, from Lactobacillus delbrueckii subsp. lactis ATCC 15808 was isolated, characterized, and used for strain identification together with ISLdl1, recently characterized as an L. delbrueckii IS element belonging to the ISL3 family. ISLdl2 was 1367 bp in size and had a 24 bp IR and an 8 bp DR. The single ORF of ISLdl2 encoded a protein of 392 aa similar to transposases of the IS256 family. ISLdl3 had a single ORF encoding a protein of 343 aa similar to transposases of the IS30 family. Finally, ISLdl4 had a single ORF encoding a protein of 406 aa and displayed homology to the transposases of the IS110 family. ISLdl4 was only slight different from ISL4 (Accession No. AY040213). ISLdl1, ISLdl2, and ISLdl4 were present in all of the 10 L. delbrueckii subsp. lactis and subsp. delbrueckii strains tested, as well as in three of the 11 L. delbrueckii subsp. bulgaricus strains tested. ISLdl3 was present only in four closely related strains of L. delbrueckii subsp. lactis. These IS elements were not observed in Lactobacillus rhamnosus, Lactobacillus acidophilus, Lactobacillus helveticus, or Lactobacillus plantarum. A cluster of IS elements, ISLdl1, ISLdl2, ISLdl3, ISLdl4, and ISL6, was observed in L. delbrueckii subsp. lactis strain ATCC 15808. Within this cluster, ISLdl4 was inserted into ISLdl1 between the left IR and the start codon of ORF455, encoding a putative transposase. Most of the integration sites of the IS elements were strain-specific. We have observed that IS elements can migrate from one strain to another as integral parts of bacterial DNA by using phage LL-H as a vehicle. We demonstrate for the first time that inverse PCR and vectorette PCR methods with primers based on sequences of the IS elements could be used for identification of L. delbrueckii strains.

Evidence for the presence of restriction/modification systems in Lactobacillus delbrueckii.

Science.gov (United States)

Suárez, Viviana; Zago, Miriam; Giraffa, Giorgio; Reinheimer, Jorge; Quiberoni, Andrea

2009-11-01

The bacteriophages Cb1/204 and Cb1/342 were obtained by induction from the commercial strain Lactobacillus delbrueckii subsp. lactis Cb1, and propagated on Lactobacillus delbrueckii subsp. lactis 204 (Lb.l 204) and Lactobacillus delbrueckii subsp. bulgaricus 342 (Lb.b 342), respectively. By cross sensitivity, it was possible to detect a delay in the lysis of Lb.l 204 with Cb1/342 phage, while the adsorption rate was high (99.5%). Modified and unmodified phages were isolated using phage Cb1/342 and strain Lb.l 204. The EOP (Efficiency of Plaquing) values for the four phages (Cb1/204, Cb1/342, Cb1/342modified and Cb1/342unmodified) suggested that an R/M system modified the original temperate phage, and the BglII-DNA restriction patterns of these phages might point out the presence of a Type II R/M system. Also, the existence of a Type I R/M system was demonstrated by PCR and nucleotide sequence, being the percentages of alignment homology with Type I R/M systems reported previously higher than 95%. In this study it was possible to demonstrate that the native phage resistant mechanisms and the occurrence of prophages in commercial host strains, contribute strongly to diversify the phage population in a factory environment.

Draft Genome Sequence of Lactobacillus delbrueckii subsp. bulgaricus CFL1, a Lactic Acid Bacterium Isolated from French Handcrafted Fermented Milk.

Science.gov (United States)

Meneghel, Julie; Dugat-Bony, Eric; Irlinger, Françoise; Loux, Valentin; Vidal, Marie; Passot, Stéphanie; Béal, Catherine; Layec, Séverine; Fonseca, Fernanda

2016-03-03

Lactobacillus delbrueckii subsp. bulgaricus (L. bulgaricus) is a lactic acid bacterium widely used for the production of yogurt and cheeses. Here, we report the genome sequence of L. bulgaricus CFL1 to improve our knowledge on its stress-induced damages following production and end-use processes. Copyright © 2016 Meneghel et al.

Influence of different proteolytic strains of Streptococcus thermophilus in co-culture with Lactobacillus delbrueckii subsp. bulgaricus on the metabolite profile of set-yoghurt

NARCIS (Netherlands)

Settachaimongkon, S.; Nout, M.J.R.; Antunes Fernandes, E.C.; Hettinga, K.A.; Vervoort, J.J.M.; Hooijdonk, van A.C.M.; Zwietering, M.H.; Smid, E.J.; Valenberg, van H.J.F.

2014-01-01

Proto-cooperation between Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus is one of the key factors that determine the fermentation process and final quality of yoghurt. In this study, the interaction between different proteolytic strains of S. thermophilus and L.

Stimulation of indigenous lactobacilli by fermented milk prepared with probiotic bacterium, Lactobacillus delbrueckii subsp. bulgaricus strain 2038, in the pigs.

Science.gov (United States)

Ohashi, Yuji; Tokunaga, Makoto; Taketomo, Naoki; Ushida, Kazunari

2007-02-01

The aim of this study was to evaluate the effect of feeding yoghurt, prepared with Lactobacillus delbrueckii subsp. bulgaricus strain 2038, on indigenous lactobacilli in the pig cecum. Three female pigs fistulated at the cecum were fed 250 g of this yoghurt that contained over 10(11) colony-forming units of L. delbrueckii subsp. bulgaricus strain 2038 with their daily meal for 2 wk. The relative abundance and the composition of cecal lactobacilli was monitored by analysis of bacterial 16S rDNA with real time PCR and amplified bacterial rDNA restriction analysis using Lactobacillus-group specific primers, respectively, for 2 wk prior to, at the end of 2 wk of and 2 wk after the administration of this yoghurt. The relative abundance of lactobacilli was significantly increased by feeding yoghurt (pdelbrueckii subsp. bulgaricus strain 2038 was not detected by amplified bacterial rDNA restriction analysis during this study. The number of operational taxonomic units (OTUs) detected was increased with feeding of the yoghurt in all pigs. At the same time, the estimated cell number of each OTU was increased with feeding of the yoghurt. It is demonstrated that continuous consumption of the probiotic lactobacilli will stimulate the growth of some indigenous lactobacilli and alter the composition of the lactobacilli.

Influence of gastrointestinal system conditions on adhesion of exopolysaccharide-producing Lactobacillus delbrueckii subsp. bulgaricus strains to caco-2 cells

Directory of Open Access Journals (Sweden)

Derya Onal Darilmaz

2011-10-01

Full Text Available This study aimed to assess the transit tolerance of potential probiotic dairy Lactobacillus strains in human uppergastrointestinal tract in vitro, and to evaluate the effect of EPS production on the viability and adhesion of these strains. Survival and adhesion of two exopolysaccharide (EPS-producing L. delbrueckii subsp. bulgaricus strains (B3 and B2 and E. coli ATCC11229 were assessed after the exposure of different pH (gastric juice and gastric plus pancreatic juice challenges. In the artificial gastric juice (pH 2, both the viability of the strain B3 and B2 was decreased. Artificial juice treatments significantly reduced the adhesion to caco-2 cells (P< 0.05. High EPS-producing B3 survived better in the adverse gastrointestinal conditions and showed better ability of adhesion to Caco-2 cells when assessed for competition with E. coli ATCC 11229 compared to low EPS-producing B2. This investigation showed that EPS production could be affected or be involved in the viability, adherence and competition of L. delbrueckii subsp. bulgaricus strains and support the potential of B3 strain for development of new probiotic products.

Increase of fruity aroma during mixed T. delbrueckii/S. cerevisiae wine fermentation is linked to specific esters enhancement.

Science.gov (United States)

Renault, Philippe; Coulon, Joana; de Revel, Gilles; Barbe, Jean-Christophe; Bely, Marina

2015-08-17

The aim of this work was to study ester formation and the aromatic impact of Torulaspora delbrueckii when used in association with Saccharomyces cerevisiae during the alcoholic fermentation of must. In order to evaluate the influence of the inoculation procedure, sequential and simultaneous mixed cultures were carried out and compared to pure cultures of T. delbrueckii and S. cerevisiae. Our results showed that mixed inoculations allowed the increase, in comparison to S. cerevisiae pure culture, of some esters specifically produced by T. delbrueckii and significantly correlated to the maximal T. delbrueckii population reached in mixed cultures. Thus, ethyl propanoate, ethyl isobutanoate and ethyl dihydrocinnamate were considered as activity markers of T. delbrueckii. On the other hand, isobutyl acetate and isoamyl acetate concentrations were systematically increased during mixed inoculations although not correlated with the development of either species but were rather due to positive interactions between these species. Favoring T. delbrueckii development when performing sequential inoculation enhanced the concentration of esters linked to T. delbrueckii activity. On the contrary, simultaneous inoculation restricted the growth of T. delbrueckii, limiting the production of its activity markers, but involved a very important production of numerous esters due to more important positive interactions between species. These results suggest that the ester concentrations enhancement via interactions during mixed modalities was due to S. cerevisiae production in response to the presence of T. delbrueckii. Finally, sensory analyses showed that mixed inoculations between T. delbrueckii and S. cerevisiae allowed to enhance the complexity and fruity notes of wine in comparison to S. cerevisiae pure culture. Furthermore, the higher levels of ethyl propanoate, ethyl isobutanoate, ethyl dihydrocinnamate and isobutyl acetate in mixed wines were found responsible for the increase of

Technological characterization and survival of the exopolysaccharide-producing strain Lactobacillus delbrueckii subsp. lactis 193 and its bile-resistant derivative 193+ in simulated gastric and intestinal juices.

Science.gov (United States)

Burns, Patricia; Vinderola, Gabriel; Reinheimer, Jorge; Cuesta, Isabel; de Los Reyes-Gavilán, Clara G; Ruas-Madiedo, Patricia

2011-08-01

The capacity of lactic acid bacteria to produce exopolysaccharides (EPS) conferring microorganisms a ropy phenotype could be an interesting feature from a technological point of view. Progressive adaptation to bile salts might render some lactobacilli able to overcome physiological gut barriers but could also modify functional properties of the strain, including the production of EPS. In this work some technological properties and the survival ability in simulated gastrointestinal conditions of Lactobacillus delbrueckii subsp. lactis 193, and Lb. delbrueckii subsp. lactis 193+, a strain with stable bile-resistant phenotype derived thereof, were characterized in milk in order to know whether the acquisition of resistance to bile could modify some characteristics of the microorganism. Both strains were able to grow and acidify milk similarly; however the production of ethanol increased at the expense of the aroma compound acetaldehyde in milk fermented by the strain 193+, with respect to milk fermented by the strain 193. Both microorganisms produced a heteropolysaccharide composed of glucose and galactose, and were able to increase the viscosity of fermented milks. In spite of the higher production yield of EPS by the bile-resistant strain 193+, it displayed a lower ability to increase viscosity than Lb. delbrueckii subsp. lactis 193. Milk increased survival in simulated gastric juice; the presence of bile improved adhesion to the intestinal cell line HT29-MTX in both strains. However, the acquisition of a stable resistance phenotype did not improve survival in simulated gastric and intestinal conditions or the adhesion to the intestinal cell line HT29-MTX. Thus, Lb. delbrueckii subsp. lactis 193 presents suitable technological properties for the manufacture of fermented dairy products; the acquisition of a stable bile-resistant phenotype modified some properties of the microorganism. This suggests that the possible use of bile-resistant derivative strains should be

Biotransformation of aflatoxin B1 and aflatoxin G1 in peanut meal by anaerobic solid fermentation of Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus.

Science.gov (United States)

Chen, Yujie; Kong, Qing; Chi, Chen; Shan, Shihua; Guan, Bin

2015-10-15

The purpose of this study was to explore the ability of anaerobic solid fermentation of Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus to biotransform aflatoxins in peanut meal. The pH of the peanut meal was adjusted above 10, and then heated for 10 min at 100 °C, 115 °C and 121 °C. The S. thermophilus and L. delbrueckii subsp. bulgaricus were precultured together in MRS broth for 48 h at 37 °C. The heated peanut meal was mixed with precultured MRS broth containing 7.0×10(8) CFU/mL of S. thermophilus and 3.0×10(3) CFU/mL of L. delbrueckii subsp. bulgaricus with the ratio of 1 to 1 (weight to volume) and incubated in anaerobic jars at 37 °C for 3 days. The aflatoxin content in the peanut meal samples was determined by HPLC. The results showed that the peanut meal contained mainly aflatoxin B1 (AFB1) (10.5±0.64 μg/kg) and aflatoxin G1 (AFG1) (18.7±0.55 μg/kg). When heat treatment was combined with anaerobic solid fermentation, the biotransformation rate of aflatoxins in peanut meal could attain 100%. The cytotoxicity of fermented peanut meal to L929 mouse connective tissue fibroblast cells was determined by MTT assay and no significant toxicity was observed in the fermented peanut meal. Furthermore, heat treatment and anaerobic solid fermentation did not change the amino acid concentrations and profile in peanut meal. Copyright © 2015 Elsevier B.V. All rights reserved.

NADH Oxidase of Streptococcus thermophilus 1131 is Required for the Effective Yogurt Fermentation with Lactobacillus delbrueckii subsp. bulgaricus 2038

OpenAIRE

SASAKI, Yasuko; HORIUCHI, Hiroshi; KAWASHIMA, Hiroko; MUKAI, Takao; YAMAMOTO, Yuji

2014-01-01

We previously reported that dissolved oxygen (DO) suppresses yogurt fermentation with an industrial starter culture composed of Lactobacillus delbrueckii subsp. bulgaricus (L. bulgaricus) 2038 and Streptococcus thermophilus 1131, and also found that reducing the DO in the medium prior to fermentation (deoxygenated fermentation) shortens the fermentation time. In this study, we found that deoxygenated fermentation primarily increased the cell number of S. thermophilus 1131 rather than that of ...

Selective and differential enumerations of Lactobacillus delbrueckii subsp. bulgaricus, Streptococcus thermophilus, Lactobacillus acidophilus, Lactobacillus casei and Bifidobacterium spp. in yoghurt--a review.

Science.gov (United States)

Ashraf, Rabia; Shah, Nagendra P

2011-10-03

Yoghurt is increasingly being used as a carrier of probiotic bacteria for their potential health benefits. To meet with a recommended level of ≥10(6) viable cells/g of a product, assessment of viability of probiotic bacteria in market preparations is crucial. This requires a working method for selective enumeration of these probiotic bacteria and lactic acid bacteria in yoghurt such as Streptococcus thermophilus, Lactobacillus delbrueckii subsp. bulgaricus, Lb. acidophilus, Lb. casei and Bifidobacterium. This chapter presents an overview of media that could be used for differential and selective enumerations of yoghurt bacteria. De Man Rogosa Sharpe agar containing fructose (MRSF), MRS agar pH 5.2 (MRS 5.2), reinforced clostridial prussian blue agar at pH 5.0 (RCPB 5.0) or reinforced clostridial agar at pH 5.3 (RCA 5.3) are suitable for enumeration of Lb. delbrueckii subsp. bulgaricus when the incubation is carried out at 45°C for 72h. S. thermophilus (ST) agar and M17 are recommended for selective enumeration of S. thermophilus. Selective enumeration of Lb. acidophilus in mixed culture could be made in Rogosa agar added with 5-bromo-4-chloro-3-indolyl-β-d-glucopyranoside (X-Glu) or MRS containing maltose (MRSM) and incubation in a 20% CO2 atmosphere. Lb. casei could be selectively enumerated on specially formulated Lb. casei (LC) agar from products containing yoghurt starter bacteria (S. thermophilus and Lb. delbrueckii subsp. bulgaricus), Lb. acidophilus, Bifidobacterium spp. and Lb. casei. Bifidobacterium could be enumerated on MRS agar supplemented with nalidixic acid, paromomycin, neomycin sulphate and lithium chloride (MRS-NPNL) under anaerobic incubation at 37°C for 72h. Copyright © 2011. Published by Elsevier B.V.

Genes involved in protein metabolism of the probiotic lactic acid bacterium Lactobacillus delbrueckii UFV H2b20.

Science.gov (United States)

Do Carmo, A P; da Silva, D F; De Oliveira, M N V; Borges, A C; De Carvalho, A F; De Moraes, C A

2011-09-01

A basic requirement for the prediction of the potential use of lactic acid bacteria (LAB) in the dairy industry is the identification of specific genes involved in flavour-forming pathways. The probiotic Lactobacillus delbrueckii UFV H2b20 was submitted to a genetic characterisation and phylogenetic analysis of genes involved in protein catabolism. Eight genes belonging to this system were identified, which possess a closely phylogenetic relationship to NCFM strains representative, as it was demonstrated for oppC and oppBII, encoding oligopeptide transport system components. PepC, PepN, and PepX might be essential for growth of LAB, probiotic or not, since the correspondent genes are always present, including in L. delbrueckii UFV H2b20 genome. For pepX gene, a probable link between carbohydrate catabolism and PepX expression may exists, where it is regulated by PepR1/CcpA-like, a common feature between Lactobacillus strains and also in L. delbrueckii UFV H2b20. The well conserved evolutionary history of the ilvE gene is evidence that the pathways leading to branched-chain amino acid degradation, such as isoleucine and valine, are similar among L. delbrueckii subsp. bulgaricus strains and L. delbrueckii UFV H2b20. Thus, the involvement of succinate in flavour formation can be attributed to IlvE activity. The presence of aminopeptidase G in L. delbrueckii UFV H2b20 genome, which is absent in several strains, might improve the proteolytic activity and effectiveness. The nucleotide sequence encoding PepG revealed that it is a cysteine endopeptidase, belonging to Peptidase C1 superfamily; sequence analysis showed 99% identity with L. delbrueckii subsp. bulgaricus ATCC 11842 pepG, whereas protein sequence analysis revealed 100% similarity with PepG from the same organism. The present study proposes a schematic model to explain how the proteolytic system of the probiotic L. delbrueckii UFV H2b20 works, based on the components identified so far.

Bacteriocin-like inhibitory activities of seven Lactobacillus delbrueckii subsp. bulgaricus strains against antibiotic susceptible and resistant Helicobacter pylori strains.

Science.gov (United States)

Boyanova, L; Gergova, G; Markovska, R; Yordanov, D; Mitov, I

2017-12-01

The aim of the study was to detect anti-Helicobacter pylori activity of seven Lactobacillus delbrueckii subsp. bulgaricus (GLB) strains by four cell-free supernatant (CFS) types. Activity of non-neutralized and non-heat-treated (CFSs1), non-neutralized and heat-treated (CFSs2), pH neutralized, catalase-treated and non-heat-treated (CFSs3), or neutralized, catalase- and heat-treated (CFSs4) CFSs against 18 H. pylori strains (11 of which with antibiotic resistance) was evaluated. All GLB strains produced bacteriocin-like inhibitory substances (BLISs), the neutralized CFSs of two GLB strains inhibited >81% of test strains and those of four GLB strains were active against >71% of antibiotic resistant strains. Two H. pylori strains were BLIS resistant. The heating did not reduce the CFS activity. Briefly, all GLB strains evaluated produced heat-stable BLISs, although GLB and H. pylori strain susceptibility patterns exhibited differences. Bacteriocin-like inhibitory substance activity can be an advantage for the probiotic choice for H. pylori infection control. In this study, anti-Helicobacter pylori activity of seven Lactobacillus delbrueckii subsp. bulgaricus (GLB) strains was evaluated by four cell-free supernatant (CFS) types. The GLB strains produced heat-stable bacteriocin-like inhibitory substances (BLISs) with a strong anti-H. pylori activity and some neutralized, catalase- and heat-treated CFSs inhibited >83% of the test strains. Bacteriocin-like inhibitory substance production of GLB strains can render them valuable probiotics in the control of H. pylori infection. © 2017 The Society for Applied Microbiology.

EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA); Scientific Opinion on the substantiation of a health claim related to a combination of Lactobacillus delbrueckii subsp. bulgaricus AY/CSL (LMG P-17224) and Streptococcus thermophilus 9Y/CSL (LMG P-17225) and “beneficial modulation

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Tetens, Inge

of a health claim related to a combination of Lactobacillus delbrueckii subsp. bulgaricus AY/CSL (LMG P-17224) and Streptococcus thermophilus 9Y/CSL (LMG P-17225) and “beneficial modulation of intestinal microflora”. The scope of the application was proposed to fall under a health claim referring to children......’s development and health. The food constituent that is the subject of the health claim, a combination of L. delbrueckii subsp. bulgaricus AY/CSL (LMG P-17224) and S. thermophilus 9Y/CSL (LMG P-17225), has not been sufficiently characterised. The claimed effect is “beneficial modulation of the intestinal...... that a cause and effect relationship has not been established between the consumption of the food constituent, the combination of L. delbrueckii subsp. bulgaricus AY/CSL (LMG P-17224) and S. thermophilus 9Y/CSL (LMG P-17225), and a beneficial physiological effect related to “beneficial modulation...

Production of Angiotensin-I-Converting-Enzyme-Inhibitory Peptides in Fermented Milks Started by Lactobacillus delbrueckii subsp. bulgaricus SS1 and Lactococcus lactis subsp. cremoris FT4

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Gobbetti, M.; Ferranti, P.; Smacchi, E.; Goffredi, F.; Addeo, F.

2000-01-01

Two fermented milks containing angiotensin-I-converting-enzyme (ACE)-inhibitory peptides were produced by using selected Lactobacillus delbrueckii subsp. bulgaricus SS1 and L. lactis subsp. cremoris FT4. The pH 4.6-soluble nitrogen fraction of the two fermented milks was fractionated by reversed-phase fast-protein liquid chromatography. The fractions which showed the highest ACE-inhibitory indexes were further purified, and the related peptides were sequenced by tandem fast atom bombardment-mass spectrometry. The most inhibitory fractions of the milk fermented by L. delbrueckii subsp. bulgaricus SS1 contained the sequences of β-casein (β-CN) fragment 6-14 (f6-14), f7-14, f73-82, f74-82, and f75-82. Those from the milk fermented by L. lactis subsp. cremoris FT4 contained the sequences of β-CN f7-14, f47-52, and f169-175 and κ-CN f155-160 and f152-160. Most of these sequences had features in common with other ACE-inhibitory peptides reported in the literature. In particular, the β-CN f47-52 sequence had high homology with that of angiotensin-II. Some of these peptides were chemically synthesized. The 50% inhibitory concentrations (IC50s) of the crude purified fractions containing the peptide mixture were very low (8.0 to 11.2 mg/liter). When the synthesized peptides were used individually, the ACE-inhibitory activity was confirmed but the IC50s increased considerably. A strengthened inhibitory effect of the peptide mixtures with respect to the activity of individual peptides was presumed. Once generated, the inhibitory peptides were resistant to further proteolysis either during dairy processing or by trypsin and chymotrypsin. PMID:10966406

Torulaspora delbrueckii for secondary fermentation in sparkling wine production.

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Canonico, Laura; Comitini, Francesca; Ciani, Maurizio

2018-09-01

In the search for the desired oenological features and flavour complexity of wines, there is growing interest in the potential use of non-Saccharomyces yeast that are naturally present in the winemaking environment. Torulaspora delbrueckii is one such yeast that has seen profitable use in mixed fermentations with Saccharomyces cerevisiae and with different grape varieties. T. delbrueckii can have positive and distinctive impacts on the overall aroma of wines, and has also been used at an industrial level. Here, T. delbrueckii was successfully used in pure and mixed secondary fermentations for sparkling wine. The two selected T. delbrueckii strains used completed the secondary fermentation 'prise de mousse' in these pure and mixed fermentations. The sparkling wines obtained with T. delbrueckii showed different aromatic compositions and sensory profiles to those of S. cerevisiae. T. delbrueckii strain DiSVA 130 showed high esters production and significantly high scores for some of the aromatic descriptors that positively influence the sensory profile of sparkling wine. Thus, the use of T. delbrueckii in pure and mixed fermentations is a suitable strategy to further develop the flavour complexity during secondary fermentation of sparkling wines. Copyright © 2018 Elsevier Ltd. All rights reserved.

Combination of Metabolomic and Proteomic Analysis Revealed Different Features among Lactobacillus delbrueckii Subspecies bulgaricus and lactis Strains While In Vivo Testing in the Model Organism Caenorhabditis elegans Highlighted Probiotic Properties

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Elena Zanni

2017-06-01

Full Text Available Lactobacillus delbrueckii represents a technologically relevant member of lactic acid bacteria, since the two subspecies bulgaricus and lactis are widely associated with fermented dairy products. In the present work, we report the characterization of two commercial strains belonging to L. delbrueckii subspecies bulgaricus, lactis and a novel strain previously isolated from a traditional fermented fresh cheese. A phenomic approach was performed by combining metabolomic and proteomic analysis of the three strains, which were subsequently supplemented as food source to the model organism Caenorhabditis elegans, with the final aim to evaluate their possible probiotic effects. Restriction analysis of 16S ribosomal DNA revealed that the novel foodborne strain belonged to L. delbrueckii subspecies lactis. Proteomic and metabolomic approaches showed differences in folate, aminoacid and sugar metabolic pathways among the three strains. Moreover, evaluation of C. elegans lifespan, larval development, brood size, and bacterial colonization capacity demonstrated that L. delbrueckii subsp. bulgaricus diet exerted beneficial effects on nematodes. On the other hand, both L. delbrueckii subsp. lactis strains affected lifespan and larval development. We have characterized three strains belonging to L. delbrueckii subspecies bulgaricus and lactis highlighting their divergent origin. In particular, the two closely related isolates L. delbrueckii subspecies lactis display different galactose metabolic capabilities. Moreover, the L. delbrueckii subspecies bulgaricus strain demonstrated potential probiotic features. Combination of omic platforms coupled with in vivo screening in the simple model organism C. elegans is a powerful tool to characterize industrially relevant bacterial isolates.

Combination of Metabolomic and Proteomic Analysis Revealed Different Features among Lactobacillus delbrueckii Subspecies bulgaricus and lactis Strains While In Vivo Testing in the Model Organism Caenorhabditis elegans Highlighted Probiotic Properties.

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Zanni, Elena; Schifano, Emily; Motta, Sara; Sciubba, Fabio; Palleschi, Claudio; Mauri, Pierluigi; Perozzi, Giuditta; Uccelletti, Daniela; Devirgiliis, Chiara; Miccheli, Alfredo

2017-01-01

Lactobacillus delbrueckii represents a technologically relevant member of lactic acid bacteria, since the two subspecies bulgaricus and lactis are widely associated with fermented dairy products. In the present work, we report the characterization of two commercial strains belonging to L. delbrueckii subspecies bulgaricus , lactis and a novel strain previously isolated from a traditional fermented fresh cheese. A phenomic approach was performed by combining metabolomic and proteomic analysis of the three strains, which were subsequently supplemented as food source to the model organism Caenorhabditis elegans , with the final aim to evaluate their possible probiotic effects. Restriction analysis of 16S ribosomal DNA revealed that the novel foodborne strain belonged to L. delbrueckii subspecies lactis . Proteomic and metabolomic approaches showed differences in folate, aminoacid and sugar metabolic pathways among the three strains. Moreover, evaluation of C. elegans lifespan, larval development, brood size, and bacterial colonization capacity demonstrated that L. delbrueckii subsp. bulgaricus diet exerted beneficial effects on nematodes. On the other hand, both L. delbrueckii subsp. lactis strains affected lifespan and larval development. We have characterized three strains belonging to L. delbrueckii subspecies bulgaricus and lactis highlighting their divergent origin. In particular, the two closely related isolates L. delbrueckii subspecies lactis display different galactose metabolic capabilities. Moreover, the L. delbrueckii subspecies bulgaricus strain demonstrated potential probiotic features. Combination of omic platforms coupled with in vivo screening in the simple model organism C. elegans is a powerful tool to characterize industrially relevant bacterial isolates.

Involvement of the ornithine decarboxylase gene in acid stress response in probiotic Lactobacillus delbrueckii UFV H2b20.

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Ferreira, A B; Oliveira, M N V de; Freitas, F S; Paiva, A D; Alfenas-Zerbini, P; Silva, D F da; Queiroz, M V de; Borges, A C; Moraes, C A de

2015-01-01

Amino acid decarboxylation is important for the maintenance of intracellular pH under acid stress. This study aims to carry out phylogenetic and expression analysis by real-time PCR of two genes that encode proteins involved in ornithine decarboxylation in Lactobacillus delbrueckii UFV H2b20 exposed to acid stress. Sequencing and phylogeny analysis of genes encoding ornithine decarboxylase and amino acid permease in L. delbrueckii UFV H2b20 showed their high sequence identity (99%) and grouping with those of L. delbrueckii subsp. bulgaricus ATCC 11842. Exposure of L. delbrueckii UFV H2b20 cells in MRS pH 3.5 for 30 and 60 min caused a significant increase in expression of the gene encoding ornithine decarboxylase (up to 8.1 times higher when compared to the control treatment). Increased expression of the ornithine decarboxylase gene demonstrates its involvement in acid stress response in L. delbrueckii UFV H2b20, evidencing that the protein encoded by that gene could be involved in intracellular pH regulation. The results obtained show ornithine decarboxylation as a possible mechanism of adaptation to an acidic environmental condition, a desirable and necessary characteristic for probiotic cultures and certainly important to the survival and persistence of the L. delbrueckii UFV H2b20 in the human gastrointestinal tract.

Effect of oligosaccharides on the growth of Lactobacillus delbrueckii subsp. bulgaricus strains isolated from dairy products.

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Ignatova, Tseteslava; Iliev, Ilia; Kirilov, Nikolai; Vassileva, Tonka; Dalgalarrondo, Michèle; Haertlé, Thomas; Chobert, Jean-Marc; Ivanova, Iskra

2009-10-28

Eighteen lactic acid bacteria (LAB) strains isolated from dairy products, all identified as Lactobacillus delbrueckii subsp. bulgaricus, were tested for their ability to grow on three different oligosaccharides: fructo-oligosaccharides (FOS), gluco-oligosaccharides (GOS) and galacto-oligosaccharides (GalOS). The growth of LAB on different oligosaccharides was very different. Study of the antimicrobial activities of these LAB indicated that the system of uptake of unusual sugars influenced in a specific way the production of antimicrobial substances (bacteriocins) specific against gram-negative bacteria. The added oligosaccharides induced LAB to form end-products of a typical mixed acid fermentation. The utilization of different types of oligosaccharides may help to explain the ability of Lactobacillus strains to compete with other bacteria in the ecosystem of the human gastro-intestinal tract.

Identification of Quorum Sensing Signal Molecule of Lactobacillus delbrueckii subsp. bulgaricus.

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Pang, Xiaoyang; Liu, Cuiping; Lyu, Pengcheng; Zhang, Shuwen; Liu, Lu; Lu, Jing; Ma, Changlu; Lv, Jiaping

2016-12-14

Many bacteria in nature use quorum sensing (QS) to regulate gene expression. The quorum sensing system plays critical roles in the adaptation of bacteria to the surrounding environment. Previous studies have shown that during high-density fermentation, the autolysis of lactic acid bacteria was regulated by the QS system, and the two-component system (TCS, LBUL_RS00115/LBUL_RS00110) is involved in the autolysis of Lactobacillus delbrueckii subsp. bulgaricus. However, the QS signal molecule, which regulates this pathway, has not been identified. In this study, we compared the genome of Lactobacillus bulgaricus ATCC BAA-365 with the locus of seven lactobacillus QS systems; the position of the QS signal molecule of Lactobacillus bulgaricus ATCC BAA-365 was predicted by bioinformatics tool. Its function was identified by in vitro experiments. Construction of TCS mutant by gene knockout of LBUL_RS00115 confirmed that the signal molecule regulates the density of the flora by the TCS (LBUL_RS00115/LBUL_RS00110). This study indicated that quorum quenching and inhibition based on the signal molecule might serve as an approach to reduce the rate of autolysis of LAB and increase the number of live bacteria in fermentation.

The genomes and comparative genomics of Lactobacillus delbrueckii phages.

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Riipinen, Katja-Anneli; Forsman, Päivi; Alatossava, Tapani

2011-07-01

Lactobacillus delbrueckii phages are a great source of genetic diversity. Here, the genome sequences of Lb. delbrueckii phages LL-Ku, c5 and JCL1032 were analyzed in detail, and the genetic diversity of Lb. delbrueckii phages belonging to different taxonomic groups was explored. The lytic isometric group b phages LL-Ku (31,080 bp) and c5 (31,841 bp) showed a minimum nucleotide sequence identity of 90% over about three-fourths of their genomes. The genomic locations of their lysis modules were unique, and the genomes featured several putative overlapping transcription units of genes. LL-Ku and c5 virions displayed peptidoglycan hydrolytic activity associated with a ~36-kDa protein similar in size to the endolysin. Unexpectedly, the 49,433-bp genome of the prolate phage JCL1032 (temperate, group c) revealed a conserved gene order within its structural genes. Lb. delbrueckii phages representing groups a (a phage LL-H), b and c possessed only limited protein sequence homology. Genomic comparison of LL-Ku and c5 suggested that diversification of Lb. delbrueckii phages is mainly due to insertions, deletions and recombination. For the first time, the complete genome sequences of group b and c Lb. delbrueckii phages are reported.

Structure determination of the neutral exopolysaccharide produced by Lactobacillus delbrueckii subsp. bulgaricus OLL1073R-1.

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Van Calsteren, Marie-Rose; Gagnon, Fleur; Nishimura, Junko; Makino, Seiya

2015-09-02

The neutral exopolysaccharide (NPS) of Lactobacillus delbrueckii subsp. bulgaricus strain OLL1073R-1 was purified and characterized. The molecular mass was 5.0×10(6) g/mol. Sugar and absolute configuration analyses gave the following composition: d-Glc, 1; d-Gal, 1.5. The NPS was also submitted to periodate oxidation followed by borohydride reduction and Smith degradation. Sugar and methylation analyses, (1)H and (13)C nuclear magnetic resonance, and mass spectrometry of the NPS or of its specifically modified products allowed determining the repeating unit sequence: {2)Glc(α1-3)Glc(β1-3)[Gal(β1-4)]Gal(β1-4)Gal(α1-}n. The structure is compared to that of exopolysaccharides produced by other Lactobacillus bulgaricus strains. Copyright © 2015. Published by Elsevier Ltd.

A model of proteolysis and amino acid biosynthesis for Lactobacillus delbrueckii subsp. bulgaricus in whey.

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Liu, Enuo; Zheng, Huajun; Hao, Pei; Konno, Tomonobu; Yu, Yao; Kume, Hisae; Oda, Munehiro; Ji, Zai-Si

2012-12-01

Lactobacillus delbrueckii subsp. bulgaricus 2038 (L. bulgaricus 2038) is a bacterium that is used as a starter for dairy products by Meiji Co., Ltd of Japan. Culturing L. bulgaricus 2038 with whey as the sole nitrogen source results in a shorter lag phase than other milk proteins under the same conditions (carbon source, minerals, and vitamins). Microarray results of gene expression revealed characteristics of amino acid anabolism with whey as the nitrogen source and established a model of proteolysis and amino acid biosynthesis for L. bulgaricus. Whey peptides and free amino acids are readily metabolized, enabling rapid entry into the logarithmic growth phase. The oligopeptide transport system is the primary pathway for obtaining amino acids. Amino acid biosynthesis maintains the balance between amino acids required for cell growth and the amount obtained from environment. The interconversion of amino acids is also important for L. bulgaricus 2038 growth.

Genetic diversity and population structure of Lactobacillus delbrueckii subspecies bulgaricus isolated from naturally fermented dairy foods.

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Song, Yuqin; Sun, Zhihong; Guo, Chenyi; Wu, Yarong; Liu, Wenjun; Yu, Jie; Menghe, Bilige; Yang, Ruifu; Zhang, Heping

2016-03-04

Lactobacillus delbrueckii subsp. bulgaricus is one of the most widely used starter culture strains in industrial fermented dairy manufacture. It is also common in naturally fermented dairy foods made using traditional methods. The subsp. bulgaricus strains found in naturally fermented foods may be useful for improving current industrial starter cultures; however, little is known regarding its genetic diversity and population structure. Here, a collection of 298 L. delbrueckii strains from naturally fermented products in Mongolia, Russia, and West China was analyzed by multi-locus sequence typing based on eight conserved genes. The 251 confirmed subsp. bulgaricus strains produced 106 unique sequence types, the majority of which were assigned to five clonal complexes (CCs). The geographical distribution of CCs was uneven, with CC1 dominated by Mongolian and Russian isolates, and CC2-CC5 isolates exclusively from Xinjiang, China. Population structure analysis suggested six lineages, L1-L6, with various homologous recombination rates. Although L2-L5 were mainly restricted within specific regions, strains belonging to L1 and L6 were observed in diverse regions, suggesting historical transmission events. These results greatly enhance our knowledge of the population diversity of subsp. bulgaricus strains, and suggest that strains from CC1 and L4 may be useful as starter strains in industrial fermentation.

Study on the effects of microencapsulated Lactobacillus delbrueckii on the mouse intestinal flora.

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Sun, Qingshen; Shi, Yue; Wang, Fuying; Han, Dequan; Lei, Hong; Zhao, Yao; Sun, Quan

2015-01-01

To evaluate the protective effects of microencapsulation on Lactobacillus delbrueckii by random, parallel experimental design. Lincomycin hydrochloride-induced intestinal malfunction mouse model was successfully established; then the L. delbrueckii microcapsule was given to the mouse. The clinical behaviour, number of intestinal flora, mucous IgA content in small intestine, IgG and IL-2 level in peripheral blood were monitored. The histological sections were also prepared. The L. delbrueckii microcapsule could have more probiotic effects as indicated by higher bifidobacterium number in cecal contents. The sIgA content in microcapsule treated group was significantly higher than that in non-encapsulated L. delbrueckii treated group (p < 0.05). Intestine pathological damage of the L. delbrueckii microcapsule-treated group showed obvious restoration. The L. delbrueckii microcapsules could relieve the intestinal tissue pathological damage and play an important role in curing antibiotic-induced intestinal flora dysfunction.

Structural investigation of cell wall polysaccharides of Lactobacillus delbrueckii subsp. bulgaricus 17.

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Vinogradov, E; Sadovskaya, I; Cornelissen, A; van Sinderen, D

2015-09-02

Lactobacilli are valuable strains for commercial (functional) food fermentations. Their cell surface-associated polysaccharides (sPSs) possess important functional properties, such as acting as receptors for bacteriophages (bacterial viruses), influencing autolytic characteristics and providing protection against antimicrobial peptides. The current report provides an elaborate molecular description of several surface carbohydrates of Lactobacillus delbrueckii subsp. bulgaricus strain 17. The cell surface of this strain was shown to contain short chain poly(glycerophosphate) teichoic acids and at least two different sPSs, designated here as sPS1 and sPS2, whose chemical structures were examined by 2D nuclear magnetic resonance spectroscopy and methylation analysis. Neutral branched sPS1, extracted with n-butanol, was shown to be composed of hexasaccharide repeating units (-[α-d-Glcp-(1-3)-]-4-β-l-Rhap2OAc-4-β-d-Glcp-[α-d-Galp-(1-3)]-4-α-Rhap-3-α-d-Galp-), while the major component of the TCA-extracted sPS2 was demonstrated to be a linear d-galactan with the repeating unit structure being (-[Gro-3P-(1-6)-]-3-β-Galf-3-α-Galp-2-β-Galf-6-β-Galf-3-β-Galp-). Copyright © 2015 Elsevier Ltd. All rights reserved.

Phage-resistance linked to cell heterogeneity in the commercial strain Lactobacillus delbrueckii subsp. lactis Ab1.

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Suárez, Viviana B; Maciel, Natalia; Guglielmotti, Daniela; Zago, Miriam; Giraffa, Giorgio; Reinheimer, Jorge

2008-12-10

The aim of this work was to study the relationship between the cell morphological heterogeneity and the phage-resistance in the commercial strain Lactobacillus delbrueckii subsp. lactis Ab1. Two morphological variants (named C and T) were isolated from this strain. Phage-resistant derivatives were isolated from them and the percentage of occurrence of confirmed phage-resistant cells was 0.001% of the total cellular population. Within these phage-resistant cell derivatives there were T (3 out of 4 total isolates) and C (1 out of 4 total isolates) variants. The study of some technological properties (e.g. proteolytic and acidifying activities) demonstrated that most of phage-resistant derivatives were not as good as the parental strain. However, for one derivative (a T variant), the technological properties were better than those of the parental strain. On the other hand, it was possible to determinate that the system of phage-resistance in the T variants was interference in adsorption step, with adsorption rates M.

Influence of different carbon sources on exopolysaccharide production by Lactobacillus delbrueckii subsp. bulgaricus (B3, G12 and Streptococcus thermophilus (W22

Directory of Open Access Journals (Sweden)

Zehra Nur Yuksekdag

2008-06-01

Full Text Available Exopolysaccharides (EPSs production was studied by Lactobacillus delbrueckii subsp. bulgaricus (B3, G12 and Streptococcus thermophilus (W22 in the medium containing various carbon sources (glucose, fructose, sucrose or lactose. For all the strains, glucose was the most efficient carbon source and B3, G12 and W22 strains produced 211, 175 and 120 EPS mg/L respectively. Also, the influence of different concentrations of glucose (5,10,15,20,25,30 g/L on EPS production and growth was studied. The results indicated that EPS production and growth were stimulated by the high glucose concentration (30 g/L.

Preparation of low galactose yogurt using cultures of Gal(+) Streptococcus thermophilus in combination with Lactobacillus delbrueckii ssp. bulgaricus.

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Anbukkarasi, Kaliyaperumal; UmaMaheswari, Thiyagamoorthy; Hemalatha, Thiagarajan; Nanda, Dhiraj Kumar; Singh, Prashant; Singh, Rameshwar

2014-09-01

Streptococcus thermophilus is an important lactic starter used in the production of yogurt. Most strains of S. thermophilus are galactose negative (Gal(-)) and are able to metabolize only glucose portion of lactose and expel galactose into the medium. This metabolic defect leads to the accumulation of free galactose in yogurt, resulting in galactosemia among consumers. Hence there is an absolute need to develop low galactose yogurt. Therefore, in this study, three galactose positive (Gal(+)) S. thermophilus strains from National Collection of Dairy Cultures (NCDC) viz. NCDC 659 (AJM), NCDC 660 (JM1), NCDC 661 (KM3) and a reference galactose negative (Gal(-)) S. thermophilus NCDC 218 were used for preparation of low galactose yogurt. In milk fermented using S. thermophilus isolates alone, NCDC 659 released less galactose (0.27 %) followed by NCDC 661 (0.3 %) and NCDC 660 (0.45 %) after 10 h at 42 °C. Milk was fermented in combination with Gal(-) L. delbrueckii subsp. bulgaricus NCDC 04, in which NCDC 659 released least galactose upto 0.49 % followed by NCDC 661 (0.51 %) and NCDC 660 (0.60 %) than reference Gal(-) NCDC 218(0.79 %). Low galactose yogurt was prepared following standard procedure using Gal(+) S. thermophilus isolates and Gal(-) L. delbrueckii subsp. bulgaricus NCDC 04 in 1:1 ratio. Among which low galactose yogurt by NCDC 659 combination contained less galactose 0.37 % followed by NCDC 661 (0.51 %), NCDC 660 (0.65 %) and reference Gal(-) NCDC 218 (0.98 %) after 4 h of fermentation. This study clearly reveals that Gal(+) S. thermophilus isolates can be paired with Gal(-) L. delbrueckii subsp. bulgaricus for developing low galactose yogurt.

Galacto-oligosaccharides as protective molecules in the preservation of Lactobacillus delbrueckii subsp. bulgaricus.

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Tymczyszyn, E Elizabeth; Gerbino, Esteban; Illanes, Andrés; Gómez-Zavaglia, Andrea

2011-04-01

In this work, the protective capacity of galacto-oligosaccharides in the preservation of Lactobacillus delbrueckii subsp. bulgaricus CIDCA 333 was evaluated. Lactobacillus bulgaricus was freeze-dried or dried over silica gel in the presence of three commercial products containing galacto-oligosaccharides. The freeze-dried samples were stored at 5 and 25°C for different periods of time. After desiccation, freeze-drying or storage, samples were rehydrated and bacterial plate counts were determined. According to the results obtained, all galacto-oligosaccharides assays demonstrated to be highly efficient in the preservation of L. bulgaricus. The higher content of galacto-oligosaccharides in the commercial products was correlated with their higher protective capacity. Galacto-oligosaccharides are widely known by their prebiotic properties. However, their role as protective molecules have not been reported nor properly explored up to now. In this work the protective capacity of galacto-oligosaccharides in the preservation of L. bulgaricus, a strain particularly sensitive to any preservation process, was demonstrated. The novel role of galacto-oligosaccharides as protective molecules opens up several perspectives in regard to their applications. The supplementation of probiotics with galacto-oligosaccharides allows the production of self-protected synbiotic products, galacto-oligosaccharides exerting both a prebiotic and protecting effect. Copyright © 2011 Elsevier Inc. All rights reserved.

Impact of mixed Torulaspora delbrueckii-Saccharomyces cerevisiae culture on high-sugar fermentation.

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Bely, Marina; Stoeckle, Philippe; Masneuf-Pomarède, Isabelle; Dubourdieu, Denis

2008-03-20

Conventional wine yeasts produce high concentrations of volatile acidity, mainly acetic acid, during high-sugar fermentation. This alcoholic fermentation by-product is highly detrimental to wine quality and, in some cases, levels may even exceed legal limits. In this study, a non-conventional species, Torulaspora delbrueckii, was used, in pure cultures and mixed with Saccharomyces cerevisiae yeast, to ferment botrytized musts. Fermentation rate, biomass growth, and the formation of volatile acidity, acetaldehyde, and glycerol were considered. This study demonstrated that T. delbrueckii, often described as a low acetic producer under standard conditions, retained this quality even in a high-sugar medium. Unlike S. cerevisiae, this species did not respond to the hyper-osmotic medium by increasing acetic production as soon as it is inoculated into the must. Nevertheless, this yeast produced low ethanol and biomass yields, and the fermentation was sluggish. As a result, T. delbrueckii fermentations do not reach the required ethanol content (14%vol.), although this species can survive at this concentration. A mixed culture of T. delbrueckii and S. cerevisiae was the best combination for improving the analytical profile of sweet wine, particularly volatile acidity and acetaldehyde production. A mixed T. delbrueckii/S. cerevisiae culture at a 20:1 ratio produced 53% less in volatile acidity and 60% less acetaldehyde than a pure culture of S. cerevisiae. Inoculating S. cerevisiae after 5 days' fermentation by T. delbrueckii had less effect on volatile acidity and acetaldehyde production and resulted in stuck fermentation. These results contribute to a better understanding of the behaviour of non-Saccharomyces and their potential application in wine industry.

Lactobacillus delbrueckii bakteriyofajı LL-H'nin konakçı spektrumu

OpenAIRE

Gökçe, Özge

2010-01-01

Bu çalışmada, 7 Lactobacillus delbrueckii ssp. lactis, 6 Lactobacillus delbrueckii ssp. bulgaricus ve 5 Lactobacillus helveticus suşu kullanılarak Lactobacillus delbrueckii bakteriyofajı LL-H'nin konakçı spektrumu incelenmiştir. Her bir suş için çift tabakalı plak titresi (double-layer plaque assay) yöntemi kullanılarak en az 2 tekrar ile adsorbsiyon kinetiği incelenmiştir. Adsorbsiyon kinetiğini incelemek için 0, 3, 10, 30 ve 50. dakikalar dikkate alınarak adsorbsiyon eğrileri oluşturulmuştu...

Homodimeric β-galactosidase from Lactobacillus delbrueckii subsp. bulgaricus DSM 20081: expression in Lactobacillus plantarum and biochemical characterization.

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Nguyen, Tien-Thanh; Nguyen, Hoang Anh; Arreola, Sheryl Lozel; Mlynek, Georg; Djinović-Carugo, Kristina; Mathiesen, Geir; Nguyen, Thu-Ha; Haltrich, Dietmar

2012-02-22

The lacZ gene from Lactobacillus delbrueckii subsp. bulgaricus DSM 20081, encoding a β-galactosidase of the glycoside hydrolase family GH2, was cloned into different inducible lactobacillal expression vectors for overexpression in the host strain Lactobacillus plantarum WCFS1. High expression levels were obtained in laboratory cultivations with yields of approximately 53000 U of β-galactosidase activity per liter of medium, which corresponds to ~170 mg of recombinant protein per liter and β-galactosidase levels amounting to 63% of the total intracellular protein of the host organism. The wild-type (nontagged) and histidine-tagged recombinant enzymes were purified to electrophoretic homogeneity and further characterized. β-Galactosidase from L. bulgaricus was used for lactose conversion and showed very high transgalactosylation activity. The maximum yield of galacto-oligosaccharides (GalOS) was approximately 50% when using an initial concentration of 600 mM lactose, indicating that the enzyme can be of interest for the production of GalOS.

Growth and viability of Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus in traditional yoghurt enriched by honey and whey protein concentrate.

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Glušac, J; Stijepić, M; Đurđević-Milošević, D; Milanović, S; Kanurić, K; Vukić, V

2015-01-01

The ability of whey protein concentrate (WPC) (1% w/v) and/or honey (2% and 4% w⁄v) to improve lactic acid bacteria (Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus) growth and viability in yoghurt during a 21 day period of storage was investigated. Another focus of this study was to examine fermentation kinetics and post-acidification rates through pH and lactic acid content measurements over the 21 day period. The addition of WPC and acacia honey accelerated fermentation and improved lactic acid bacteria (LAB) growth over the 21 days, but honey proportion did not significantly affect the viability of LAB. Moreover, adding honey and WPC did not support the overproduction of lactic acid, which positively influenced yoghurt stability during the 21 day storage period.

Generation and Characterization of Environmentally Sensitive Variants of the β-Galactosidase from Lactobacillus delbrueckii subsp. bulgaricus

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Yoast, Sienna; Adams, Robin M.; Mainzer, Stanley E.; Moon, Keith; Palombella, Anthony L.; Schmidt, Brian F.

1994-01-01

A method is described for generating and screening variants of the β-galactosidase from Lactobacillus delbrueckii subsp. bulgaricus sensitive to several environmental stresses, with potential application in the food industry. Chemical mutagenesis with hydroxylamine or methoxylamine was performed on the β-galactosidase gene carried on an Escherichia coli expression vector. Mutants sensitive to cold, heat, low pH, low magnesium concentration, and the presence of urea were isolated by screening for reduced color development on β-galactosidase indicator plates. The mutations responsible for three variant β-galactosidases were localized, and the base substitutions were determined by DNA sequencing. The amino acid alterations associated with one low-pH-sensitive (pHs) and two urea-sensitive (Us) variants correspond to P584L (pHs1), G400S/R479Q (Us26), and G167E/E168K/E363K/V492M (Us17), respectively. Mutant pHs1 is also heat, cold, low magnesium, and urea sensitive; Us26 is also cold sensitive; and Us17 is also low-pH sensitive. PMID:16349230

Torulaspora delbrueckii contribution in mixed brewing fermentations with different Saccharomyces cerevisiae strains.

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Canonico, Laura; Comitini, Francesca; Ciani, Maurizio

2017-10-16

In recent years, there has been growing demand for distinctive high quality beer. Fermentation management has a fundamental role in beer quality and the levels of aroma compounds. Use of non-conventional yeast has been proposed to enhance beer bioflavor. In the present work we investigated mixed fermentations using three commercial Saccharomyces cerevisiae strains, without and with addition of a selected Torulaspora delbrueckii strain evaluating their interactions, as well as the aroma profiles. At the S. cerevisiae/T. delbrueckii co-inoculation ratio of 1:20, viable cell counts indicated that T. delbrueckii dominated all of the three combinations. In the mixed fermentations, T. delbrueckii provided higher levels of higher alcohols (excepting of β-phenyl ethanol), in contrast to data obtained in winemaking, where higher alcohols had lower levels. Moreover, mixed fermentations showed significantly higher ethyl acetate (from 5 to 16mg/L) and isoamyl acetate (from 0.019 to 0.128mg/L), and were generally lower in ethyl hexanoate and ethyl octanoate. Therefore, irrespective of S. cerevisiae strain, T. delbrueckii influenced on all mixed fermentations. On the other hand, the mixed fermentations were also affected by each of the three S. cerevisiae strains, which resulted in beers with distinctive flavors. Copyright © 2017 Elsevier B.V. All rights reserved.

Subcellular membrane fluidity of Lactobacillus delbrueckii subsp. bulgaricus under cold and osmotic stress.

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Meneghel, Julie; Passot, Stéphanie; Cenard, Stéphanie; Réfrégiers, Matthieu; Jamme, Frédéric; Fonseca, Fernanda

2017-09-01

Cryopreservation of lactic acid bacteria may lead to undesirable cell death and functionality losses. The membrane is the first target for cell injury and plays a key role in bacterial cryotolerance. This work aimed at investigating at a subcellular resolution the membrane fluidity of two populations of Lactobacillus delbrueckii subsp. bulgaricus when subjected to cold and osmotic stresses associated to freezing. Cells were cultivated at 42 °C in mild whey medium, and they were exposed to sucrose solutions of different osmolarities (300 and 1800 mOsm L -1 ) after harvest. Synchrotron fluorescence microscopy was used to measure membrane fluidity of cells labeled with the cytoplasmic membrane probe 1-[4 (trimethylamino) phenyl]-6-phenyl-1,3,5-hexatriene (TMA-DPH). Images were acquired at 25 and 0 °C, and more than a thousand cells were individually analyzed. Results revealed that a bacterial population characterized by high membrane fluidity and a homogeneous distribution of fluidity values appeared to be positively related to freeze-thaw resistance. Furthermore, rigid domains with different anisotropy values were observed and the occurrence of these domains was more important in the freeze-sensitive bacterial population. The freeze-sensitive cells exhibited a broadening of existing highly rigid lipid domains with osmotic stress. The enlargement of domains might be ascribed to the interaction of sucrose with membrane phospholipids, leading to membrane disorganization and cell degradation.

Physiological Study of Lactobacillus delbrueckii subsp. bulgaricus Strains in a Novel Chemically Defined Medium

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Chervaux, Christian; Ehrlich, S. Dusko; Maguin, Emmanuelle

2000-01-01

We developed a chemically defined medium called milieu proche du lait (MPL), in which 22 Lactobacillus delbrueckii subsp. bulgaricus (L. bulgaricus) strains exhibited growth rates ranging from 0.55 to 1 h−1. MPL can also be used for cultivation of other lactobacilli and Streptococcus thermophilus. The growth characteristics of L. bulgaricus in MPL containing different carbon sources were determined, including an initial characterization of the phosphotransferase system transporters involved. For the 22 tested strains, growth on lactose was faster than on glucose, mannose, and fructose. Lactose concentrations below 0.4% were limiting for growth. We isolated 2-deoxyglucose-resistant mutants from strains CNRZ397 and ATCC 11842. CNRZ397-derived mutants were all deficient for glucose, fructose, and mannose utilization, indicating that these three sugars are probably transported via a unique mannose-specific-enzyme-II-like transporter. In contrast, mutants of ATCC 11842 exhibited diverse phenotypes, suggesting that multiple transporters may exist in that strain. We also developed a protein labeling method and verified that exopolysaccharide production and phage infection can occur in MPL. The MPL medium should thus be useful in conducting physiological studies of L. bulgaricus and other lactic acid bacteria under well controlled nutritional conditions. PMID:11097906

Strand-specific RNA-seq analysis of the Lactobacillus delbrueckii subsp. bulgaricus transcriptome.

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Zheng, Huajun; Liu, Enuo; Shi, Tao; Ye, Luyi; Konno, Tomonobu; Oda, Munehiro; Ji, Zai-Si

2016-02-01

Lactobacillus delbrueckii subsp. bulgaricus 2038 (Lb. bulgaricus 2038) is an industrial bacterium that is used as a starter for dairy products. We proposed several hypotheses concerning its industrial features previously. Here, we utilized RNA-seq to explore the transcriptome of Lb. bulgaricus 2038 from four different growth phases under whey conditions. The most abundantly expressed genes in the four stages were mainly involved in translation (for the logarithmic stage), glycolysis (for control/lag stages), lactic acid production (all the four stages), and 10-formyl tetrahydrofolate production (for the stationary stage). The high expression of genes like d-lactate dehydrogenase was thought as a result of energy production, and consistent expression of EPS synthesis genes, the restriction-modification (RM) system and the CRISPR/Cas system were validated for explaining the advantage of this strain in yoghurt production. Several postulations, like NADPH production through GapN bypass, converting aspartate into carbon-skeleton intermediates, and formate production through degrading GTP, were proved not working under these culture conditions. The high expression of helicase genes and co-expressed amino acids/oligopeptides transporting proteins indicated that the helicase might mediate the strain obtaining nitrogen source from the environment. The transport system of Lb. bulgaricus 2038 was found to be regulated by antisense RNA, hinting the potential application of non-coding RNA in regulating lactic acid bacteria (LAB) gene expression. Our study has primarily uncovered Lb. bulgaricus 2038 transcriptome, which could gain a better understanding of the regulation system in Lb. bulgaricus and promote its industrial application.

Pyelonephritis and Bacteremia from Lactobacillus delbrueckii

OpenAIRE

DuPrey, Kevin M.; McCrea, Leon; Rabinowitch, Bonnie L.; Azad, Kamran N.

2012-01-01

Lactobacilli are normal colonizers of the oropharynx, gastrointestinal tract, and vagina. Infection is rare, but has been reported in individuals with predisposing conditions. Here we describe the case of a woman with pyelonephritis and bacteremia in which Lactobacillus delbrueckii was determined to be the causative agent.

Comparison of the Growth of Lactobacillus delbrueckii, L. paracasei and L. plantarum on Inulin in Co-culture Systems.

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Takagi, Risa; Tsujikawa, Yuji; Nomoto, Ryohei; Osawa, Ro

2014-01-01

Lactobacillus delbrueckii TU-1, which apparently takes intact inulin into its cells and then degrades it intracellularly, was co-cultured in vitro with L. paracasei KTN-5, an extracellular inulin degrader; or L. plantarum 22A-3, a strain that is able to utilize fructose but not inulin; or both in order to prequalify inulin as a prebiotic agent in vivo. When L. delbrueckii TU-1 was co-cultured with L. paracasei KTN-5 on fructose or inulin, the growth of L. delbrueckii TU-1 on inulin was markedly higher than that of L. paracasei KTN-5, whereas the growth of L. delbrueckii TU-1 on fructose was much lower than that of L. paracasei KTN-5. These results suggest that L. delbrueckii TU-1 and L. paracasei KTN-5 were efficient at utilizing inulin and fructose, respectively. When L. plantarum 22A-3 was co-cultured with L. delbrueckii TU-1 on inulin, the growth of L. plantarum 22A-3 was enhanced by L. paracasei KTN-5 but not by L. delbrueckii TU-1, suggesting that the fructose moiety that L. paracasei KTN-5 released temporarily into the medium was "scavenged" by L. plantarum 22A-3. Thus, L. delbrueckii TU-1, L. paracasei KTN-5, and L. plantarum 22A-3 were then cultured altogether on inulin. The growth of L. delbrueckii TU-1 was unaffected but that of L. paracasei KTN-5 was markedly suppressed. This evidence suggests that prebiotic use of inulin supported the selective growth of intracellular inulin degraders such as L. delbrueckii rather than extracellular inulin degraders such as L. paracasei in the host microbiota.

In silico analysis of amino acid biosynthesis and proteolysis in Lactobacillus delbrueckii subsp. bulgaricus 2038 and the implications for bovine milk fermentation.

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Zheng, Huajun; Liu, Enuo; Hao, Pei; Konno, Tomonobu; Oda, Munehiro; Ji, Zai-Si

2012-08-01

The amino acid biosynthesis pathway and proteolytic system of Lactobacillus delbrueckii subsp. bulgaricus 2038 (L. bulgaricus 2038), a mainstay of large-scale yogurt production, were modeled based on its genomic sequence. L. bulgaricus 2038 retains more potential for amino acid synthesis and a more powerful proteolytic system than other L. bulgaricus strains, but favors amino acid uptake over de novo synthesis. Free amino acids and peptides in bovine milk provide the main nitrogen sources; whey is more important than casein for L. bulgaricus during fermentation. Free amino acids are imported by amino acid permeases and by ABC-type transport systems whereas exogenous oligopeptides are imported by ABC-type proteins only. Histidine is neither synthesized nor imported singly, which might explain why L. bulgaricus cannot grow in synthetic media.

Positive selection on D-lactate dehydrogenases of Lactobacillus delbrueckii subspecies bulgaricus.

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Zhang, Jifeng; Gong, Guangyu; Wang, Xiao; Zhang, Hao; Tian, Weidong

2015-08-01

Lactobacillus delbrueckii has been widely used for yogurt fermentation. It has genes encoding both D- and L-type lactate dehydrogenases (LDHs) that catalyse the production of L(+) or D(-) stereoisomer of lactic acid. D-lactic acid is the primary lactate product by L. delbrueckii, yet it cannot be metabolised by human intestine. Since it has been domesticated for long time, an interesting question arises regarding to whether the selection pressure has affected the evolution of both L-LDH and D-LDH genes in the genome. To answer this question, in this study the authors first investigated the evolution of these two genes by constructing phylogenetic trees. They found that D-LDH-based phylogenetic tree could better represent the phylogenetic relationship in the acidophilus complex than L-LDH-based tree. They next investigated the evolutions of LDH genes of L. delbrueckii at amino acid level, and found that D-LDH gene in L. delbrueckii is positively selected, possibly a consequence of long-term domestication. They further identified four amino acids that are under positive selection. One of them, V261, is located at the centre of three catalytic active sites, indicating likely functional effects on the enzyme activity. The selection from the domestication process thus provides direction for future engineering of D-LDH.

A two component system is involved in acid adaptation of Lactobacillus delbrueckii subsp. bulgaricus.

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Cui, Yanhua; Liu, Wei; Qu, Xiaojun; Chen, Zhangting; Zhang, Xu; Liu, Tong; Zhang, Lanwei

2012-05-20

The Gram-positive bacterium Lactobacillus delbrueckii subsp. bulgaricus is of vital importance to the food industry, especially to the dairy industry. Two component systems (TCSs) are one of the most important mechanisms for environmental sensing and signal transduction in the majority of Gram-positive and Gram-negative bacteria. A typical TCS consists of a histidine protein kinase (HPK) and a cytoplasmic response regulator (RR). To investigate the functions of TCSs during acid adaptation in L. bulgaricus, we used quantitative PCR to reveal how TCSs expression changes during acid adaptation. Two TCSs (JN675228/JN675229 and JN675230/JN675231) and two HPKs (JN675236 and JN675240) were induced during acid adaptation. These TCSs were speculated to be related with the acid adaptation ability of L. bulgaricus. The mutants of JN675228/JN675229 were constructed in order to investigate the functions of JN675228/JN675229. The mutants showed reduced acid adaptation compared to that of wild type, and the complemented strains were similar to the wild-type strain. These observations suggested that JN675228 and JN675229 were involved in acid adaptation in L. bulgaricus. The interaction between JN675228 and JN675229 was identified by means of yeast two-hybrid system. The results indicated there is interaction between JN675228 and JN675229. Crown Copyright © 2011. Published by Elsevier GmbH. All rights reserved.

Pyelonephritis and Bacteremia from Lactobacillus delbrueckii

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Kevin M. DuPrey

2012-01-01

Full Text Available Lactobacilli are normal colonizers of the oropharynx, gastrointestinal tract, and vagina. Infection is rare, but has been reported in individuals with predisposing conditions. Here we describe the case of a woman with pyelonephritis and bacteremia in which Lactobacillus delbrueckii was determined to be the causative agent.

Genome Sequence of Torulaspora delbrueckii NRRL Y-50541, Isolated from Mezcal Fermentation.

Science.gov (United States)

Gomez-Angulo, Jorge; Vega-Alvarado, Leticia; Escalante-García, Zazil; Grande, Ricardo; Gschaedler-Mathis, Anne; Amaya-Delgado, Lorena; Arrizon, Javier; Sanchez-Flores, Alejandro

2015-07-23

Torulaspora delbrueckii presents metabolic features interesting for biotechnological applications (in the dairy and wine industries). Recently, the T. delbrueckii CBS 1146 genome, which has been maintained under laboratory conditions since 1970, was published. Thus, a genome of a new mezcal yeast was sequenced and characterized and showed genetic differences and a higher genome assembly quality, offering a better reference genome. Copyright © 2015 Gomez-Angulo et al.

Fig juice Fortified with Inulin and Lactobacillus Delbrueckii: A Promising Functional Food

Directory of Open Access Journals (Sweden)

Sima Khezri

2018-03-01

Full Text Available Background and Objective: Nowadays, consumption of functional foods is favored because of their health promoting characteristics. Also there is an increasing demand for nondairy products because of lactose intolerance in dairies. Fig juice as a source of dietary fiber and other nutrients would be a functional food. Adding probiotics and prebiotics makes it more functional for daily use. No study has yet been done on synbiotic fig juice. Accordingly, the aim of this study was to characterize synbiotic fig juice prepared by Lactobacillus delbrueckii and inulin.Material and Methods: Samples consisted of control fig juice; fig juice fermented by Lactobacillus delbrueckii (probiotic and fig juice containing inulin fermented by Lactobacillus delbrueckii (synbiotic were produced. Physico-chemical parameters, total phenolic content, antioxidant capacity and microbial survival aspects were analyzed during the fermentation period. Aforementioned parameters were also evaluated in 4 weeks with one-week time intervals. Sensory characteristics of fig juices were assessed in the second week of storage.Results and Conclusion: The results showed significant differences among treatments (p≤0.05 in physico-chemical indices during incubation and storage time. Total phenolic content and antioxidant capacity of fermented fig juices were significantly increased in comparison to the control samples (p≤0.05. Viability of Lactobacillus delbrueckii was increased in both probiotic and synbiotic treatments during incubation; but a significant reduction was observed during storage time. Sensory analysis revealed that there were significant differences in terms of odor, taste and overall acceptance between the fermented fig juices and control (p≤0.05 and the highest scores were obtained for control. Considering viable counts of Lactobacillus delbrueckii depicted that fermented fig juice could be a suitable medium for survival and proliferation of Lactobacillus

Fast real-time polymerase chain reaction for quantitative detection of Lactobacillus delbrueckii bacteriophages in milk.

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Martín, Maria Cruz; del Rio, Beatriz; Martínez, Noelia; Magadán, Alfonso H; Alvarez, Miguel A

2008-12-01

One of the main microbiological problems of the dairy industry is the susceptibility of starter bacteria to virus infections. Lactobacillus delbrueckii, a component of thermophilic starter cultures used in the manufacture of several fermented dairy products, including yogurt, is also sensitive to bacteriophage attacks. To avoid the problems associated with these viruses, quick and sensitive detection methods are necessary. In the present study, a fast real-time quantitative polymerase chain reaction assay for the direct detection and quantification of L. delbrueckii phages in milk was developed. A set of primers and a TaqMan MGB probe was designed, based on the lysin gene sequence of different L. delbrueckii phages. The results show the proposed method to be a rapid (total processing time 30 min), specific and highly sensitive technique for detecting L. delbrueckii phages in milk.

Sugar utilization patterns and respiro-fermentative metabolism in the baker's yeast Torulaspora delbrueckii.

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Alves-Araújo, C; Pacheco, A; Almeida, M J; Spencer-Martins, I; Leão, C; Sousa, M J

2007-03-01

The highly osmo- and cryotolerant yeast species Torulaspora delbrueckii is an important case study among the non-Saccharomyces yeast species. The strain T. delbrueckii PYCC 5321, isolated from traditional corn and rye bread dough in northern Portugal, is considered particularly interesting for the baking industry. This paper reports the sugar utilization patterns of this strain, using media with glucose, maltose and sucrose, alone or in mixtures. Kinetics of growth, biomass and ethanol yields, fermentation and respiration rates, hydrolase activities and sugar uptake rates were used to infer the potential applied relevance of this yeast in comparison to a conventional baker's strain of Saccharomyces cerevisiae. The results showed that both maltase and maltose transport in T. delbrueckii were subject to glucose repression and maltose induction, whereas invertase was subject to glucose control but not dependent on sucrose induction. A comparative analysis of specific sugar consumption rates and transport capacities suggests that the transport step limits both glucose and maltose metabolism. Specific rates of CO(2) production and O(2) consumption showed a significantly higher contribution of respiration to the overall metabolism in T. delbrueckii than in S. cerevisiae. This was reflected in the biomass yields from batch cultures and could represent an asset for the large-scale production of the former species. This work contributes to a better understanding of the physiology of a non-conventional yeast species, with a view to the full exploitation of T. delbrueckii by the baking industry.

Genetic Variation of Lactobacillus delbrueckii subsp. lactis Bacteriophages Isolated from Cheese Processing Plants in Finland

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Forsman, Päivi; Alatossava, Tapani

1991-01-01

The genomes of four Lactobacillus delbrueckii subsp. lactis bacteriophages were characterized by restriction endonuclease mapping, Southern hybridization, and heteroduplex analysis. The phages were isolated from different cheese processing plants in Finland between 1950 and 1972. All four phages had a small isometric head and a long noncontractile tail. Two different types of genome (double-stranded DNA) organization existed among the different phages, the pac type and the cos type, corresponding to alternative types of phage DNA packaging. Three phages belonged to the pac type, and a fourth was a cos-type phage. The pac-type phages were genetically closely related. In the genomes of the pac-type phages, three putative insertion/deletions (0.7 to 0.8 kb, 1.0 kb, and 1.5 kb) and one other region (0.9 kb) containing clustered base substitutions were discovered and localized. At the phenotype level, three main differences were observed among the pac-type phages. These concerned two minor structural proteins and the efficiency of phage DNA packaging. The genomes of the pac-type phages showed only weak homology with that of the cos-type phage. Phage-related DNA, probably a defective prophage, was located in the chromosome of the host strain sensitive to the cos-type phage. This DNA exhibited homology under stringent conditions to the pac-type phages. Images PMID:16348513

Difference in Degradation Patterns on Inulin-type Fructans among Strains of Lactobacillus delbrueckii and Lactobacillus paracasei.

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Tsujikawa, Yuji; Nomoto, Ryohei; Osawa, Ro

2013-01-01

Lactobacillus delbrueckii strains were assessed for their degradation patterns of various carbohydrates with specific reference to inulin-type fructans in comparison with those of Lactobacillus paracasei strains. Firstly, growth curves on glucose, fructose, sucrose and inulin-type fructans with increasing degrees of fructose polymerization (i.e., 1-kestose, fructo-oligosaccharides and inulin) of the strains were compared. L. paracasei DSM 20020 grew well on all these sugars, while the growth rates of the 4 L. delbrueckii strains were markedly higher on the fructans with a greater degree of polymerization than on fructose and sucrose. Secondly, sugar compositions of spent cultures of the strains of L. delbrueckii and L. paracasei grown in mMRS containing either the fructans or inulin were determined by thin layer chromatography, in which the spent cultures of L. paracasei DSM 20020 showed spots of short fructose and sucrose fractions, whereas those of the L. delbrueckii strains did not show such spots at all. These results suggest that, unlike the L. paracasei strains, the L. delbrueckii strains do not degrade the inulin-type fructans extracellularly, but transport the fructans capable of greater polymerization preferentially into their cells to be degraded intracellularly for their growth.

TdPIR minisatellite fingerprinting as a useful new tool for Torulaspora delbrueckii molecular typing.

Science.gov (United States)

Canonico, Laura; Comitini, Francesca; Ciani, Maurizio

2015-05-04

Torulaspora delbrueckii yeast strains are being increasingly applied at the industrial level, such as in the winemaking process, and so their identification and characterisation require effective, fast, accurate, reproducible and reliable approaches. Therefore, the development of typing techniques that allow discrimination at the strain level will provide an essential tool for those working with T. delbrueckii strains. Here, 28 T. delbrueckii strains from various substrates were characterised using different PCR-fingerprinting molecular methods: random amplified polymorphic DNA with polymerase chain reaction (RAPD-PCR), minisatellites SED1, AGA1, DAN4 and the newly designed T. delbrueckii (Td)PIR, and microsatellites (GAC)5 and (GTG)5. The aim was to determine and compare the efficacies, reproducibilities and discriminating powers of these molecular methods. RAPD-PCR using the M13 primers and the newly designed TdPIR3 minisatellite primer pair provided discrimination of the greatest number of T. delbrueckii strains. TdPIR3 clustered the 28 strains into 16 different groups with an efficiency of 100%, while M13 clustered the strains into 17 different groups, although with a lower efficiency of 89%. Moreover, the TdPIR3 primers showed reproducible profiles when the stringency of the PCR protocol was varied, which highlighted the great robustness of this technique. In contrast, variation of the stringency of the M13 PCR protocol resulted in modification of the amplified profiles, which suggested low reproducibility of this technique. Copyright © 2015 Elsevier B.V. All rights reserved.

Lactobacillus delbrueckii ssp. bulgaricus thermotolerance

OpenAIRE

Gouesbet , Gwenola; Jan , Gwenaël; Boyaval , Patrick

2001-01-01

International audience; Lactobacillus delbrueckii ssp. bulgaricus is a lactic acid bacterium widely used in the dairy food industry. Since the industrial processes are a succession of constraints, it is essential to understand the behaviour of L. bulgaricus when facing usual stresses. The influence of heat stress was investigated on the viability of L. bulgaricus cells grown in a chemically defined medium. The susceptibility of cells to heat-shock was obvious only above 55 $^{\\circ}$C. We inv...

Galacto-oligosaccharides and lactulose as protectants against desiccation of Lactobacillus delbrueckii subsp. bulcaricus.

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Santos, Mauricio I; Araujo-Andrade, Cuauhtémoc; Esparza-Ibarra, Edgar; Tymczyszyn, Elizabeth; Gómez-Zavaglia, Andrea

2014-01-01

Lactobacillus delbrueckii subsp. bulgaricus CIDCA 333 was dehydrated on desiccators containing silica gel in the presence of 20% w/w of two types of galacto-oligosaccharides (GOS Biotempo and GOS Cup Oligo H-70®) and lactulose, until no changes in water desorption were detected. After rehydration, bacterial growth was monitored at 37°C by determining: (a) the absorbance at 600 nm and (b) the near infrared spectra (NIR). Principal component analysis (PCA) was then performed on the NIR spectra of samples dehydrated in all conditions. A multiparametric flow cytometry assay was carried out using carboxyfluorescein diacetate and propidium iodide probes to determine the relative composition of damaged, viable, and dead bacteria throughout the growth kinetics. The absorbance at 600 nm and the position of the second derivative band at ∼1370 nm were plotted against the time of incubation. The efficiency of the protectants was GOS Biotempo > GOS Cup Oligo H-70®  > lactulose. The better protectant capacity of GOS Biotempo was explained on the basis of the lower contribution of damaged cells immediately after rehydration (t = 0). PCA showed three groups along PC1, corresponding to the lag, exponential and stationary phases of growth, which explained 99% of the total variance. Along PC2, two groups were observed, corresponding to damaged or viable cells. The results obtained support the use of NIR to monitor the recovery of desiccated microorganisms in real time and without the need of chemical reagents. The use of GOS and lactulose as protectants in dehydration/rehydration processes was also supported. © 2014 American Institute of Chemical Engineers.

Effects of new Torulaspora delbrueckii killer yeasts on the must fermentation kinetics and aroma compounds of white table wine.

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Velázquez, Rocío; Zamora, Emiliano; Álvarez, María L; Hernández, Luis M; Ramírez, Manuel

2015-01-01

Torulaspora delbrueckii is becoming widely recommended for improving some specific characteristics of wines. However, its impact on wine quality is still far from satisfactory at the winery level, mostly because it is easily replaced by Saccharomyces cerevisiae-like yeasts during must fermentation. New T. delbrueckii killer strains were here isolated and selected for winemaking. They killed S. cerevisiae yeasts and were able to dominate and complete the fermentation of sterile grape must. Sequential yeast inoculation of non-sterile white must with T. delbrueckii followed by S. cerevisiae did not ensure T. delbrueckii dominance or wine quality improvement. Only a single initial must inoculation at high cell concentrations allowed the T. delbrueckii killer strains to dominate and complete the must fermentation to reach above 11% ethanol, but not the non-killer strains. None of the wines underwent malolactic fermentation as long as the must had low turbidity and pH. Although no statistically significant differences were found in the wine quality score, the S. cerevisiae-dominated wines were preferred over the T. delbrueckii-dominated ones because the former had high-intensity fresh fruit aromas while the latter had lower intensity, but nevertheless nice and unusual dried fruit/pastry aromas. Except for ethyl propanoate and 3-ethoxy-1-propanol, which were more abundant in the T. delbrueckii-dominated wines, most of the compounds with fresh fruit odor descriptors, including those with the greatest odor activity values (isoamyl acetate, ethyl hexanoate, and ethyl octanoate), were more abundant in the S. cerevisiae-dominated wines. The low relative concentrations of these fruity compounds made it possible to detect in the T. delbrueckii-dominated wines the low-relative-concentration compounds with dried fruit and pastry odors. An example was γ-ethoxy-butyrolactone which was significantly more abundant in these wines than in those dominated by S. cerevisiae.

Reduction of the off-flavor volatile generated by the yogurt starter culture including Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus in soymilk.

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Kaneko, Daisuke; Igarashi, Toshinori; Aoyama, Kenji

2014-02-19

Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus establish a symbiotic relationship in milk; however, S. thermophilus predominantly grows in soymilk. This study determined that excess diacetyl was notably generated mainly by S. thermophilus in soymilk, and this flavor compound created an unpleasant odor in fermented soymilk. The addition of l-valine to soymilk reduced the amount of diacetyl and increased the levels of acetoin during fermentation by S. thermophilus . In addition, it was found that the expression of the ilvC gene was repressed and that of the als and aldB genes was stimulated in S. thermophilus by l-valine. Sensory evaluations with the triangle difference test and a preference test showed that the soymilk fermented with l-valine was significantly preferred compared with that without l-valine. In this study, we successfully controlled the metabolic flux of S. thermophilus in soymilk and produced more favorable fermented soymilk without the use of genetically modified lactic acid bacteria strains.

Complete sequencing and pan-genomic analysis of Lactobacillus delbrueckii subsp. bulgaricus reveal its genetic basis for industrial yogurt production.

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Hao, Pei; Zheng, Huajun; Yu, Yao; Ding, Guohui; Gu, Wenyi; Chen, Shuting; Yu, Zhonghao; Ren, Shuangxi; Oda, Munehiro; Konno, Tomonobu; Wang, Shengyue; Li, Xuan; Ji, Zai-Si; Zhao, Guoping

2011-01-17

Lactobacillus delbrueckii subsp. bulgaricus (Lb. bulgaricus) is an important species of Lactic Acid Bacteria (LAB) used for cheese and yogurt fermentation. The genome of Lb. bulgaricus 2038, an industrial strain mainly used for yogurt production, was completely sequenced and compared against the other two ATCC collection strains of the same subspecies. Specific physiological properties of strain 2038, such as lysine biosynthesis, formate production, aspartate-related carbon-skeleton intermediate metabolism, unique EPS synthesis and efficient DNA restriction/modification systems, are all different from those of the collection strains that might benefit the industrial production of yogurt. Other common features shared by Lb. bulgaricus strains, such as efficient protocooperation with Streptococcus thermophilus and lactate production as well as well-equipped stress tolerance mechanisms may account for it being selected originally for yogurt fermentation industry. Multiple lines of evidence suggested that Lb. bulgaricus 2038 was genetically closer to the common ancestor of the subspecies than the other two sequenced collection strains, probably due to a strict industrial maintenance process for strain 2038 that might have halted its genome decay and sustained a gene network suitable for large scale yogurt production.

NADH Oxidase of Streptococcus thermophilus 1131 is Required for the Effective Yogurt Fermentation with Lactobacillus delbrueckii subsp. bulgaricus 2038.

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Sasaki, Yasuko; Horiuchi, Hiroshi; Kawashima, Hiroko; Mukai, Takao; Yamamoto, Yuji

2014-01-01

We previously reported that dissolved oxygen (DO) suppresses yogurt fermentation with an industrial starter culture composed of Lactobacillus delbrueckii subsp. bulgaricus (L. bulgaricus) 2038 and Streptococcus thermophilus 1131, and also found that reducing the DO in the medium prior to fermentation (deoxygenated fermentation) shortens the fermentation time. In this study, we found that deoxygenated fermentation primarily increased the cell number of S. thermophilus 1131 rather than that of L. bulgaricus 2038, resulting in earlier l-lactate and formate accumulation. Measurement of the DO concentration and hydrogen peroxide generation in the milk medium suggested that DO is mainly removed by S. thermophilus 1131. The results using an H2O-forming NADH oxidase (Nox)-defective mutant of S. thermophilus 1131 revealed that Nox is the major oxygen-consuming enzyme of the bacterium. Yogurt fermentation with the S. thermophilus Δnox mutant and L. bulgaricus 2038 was significantly slower than with S. thermophilus 1131 and L. bulgaricus 2038, and the DO concentrations of the mixed culture did not decrease to less than 2 mg/kg within 3 hr. These observations suggest that Nox of S. thermophilus 1131 contributes greatly to yogurt fermentation, presumably by removing the DO in milk.

Complete sequencing and pan-genomic analysis of Lactobacillus delbrueckii subsp. bulgaricus reveal its genetic basis for industrial yogurt production.

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Pei Hao

Full Text Available Lactobacillus delbrueckii subsp. bulgaricus (Lb. bulgaricus is an important species of Lactic Acid Bacteria (LAB used for cheese and yogurt fermentation. The genome of Lb. bulgaricus 2038, an industrial strain mainly used for yogurt production, was completely sequenced and compared against the other two ATCC collection strains of the same subspecies. Specific physiological properties of strain 2038, such as lysine biosynthesis, formate production, aspartate-related carbon-skeleton intermediate metabolism, unique EPS synthesis and efficient DNA restriction/modification systems, are all different from those of the collection strains that might benefit the industrial production of yogurt. Other common features shared by Lb. bulgaricus strains, such as efficient protocooperation with Streptococcus thermophilus and lactate production as well as well-equipped stress tolerance mechanisms may account for it being selected originally for yogurt fermentation industry. Multiple lines of evidence suggested that Lb. bulgaricus 2038 was genetically closer to the common ancestor of the subspecies than the other two sequenced collection strains, probably due to a strict industrial maintenance process for strain 2038 that might have halted its genome decay and sustained a gene network suitable for large scale yogurt production.

Complete Sequencing and Pan-Genomic Analysis of Lactobacillus delbrueckii subsp. bulgaricus Reveal Its Genetic Basis for Industrial Yogurt Production

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Ding, Guohui; Gu, Wenyi; Chen, Shuting; Yu, Zhonghao; Ren, Shuangxi; Oda, Munehiro; Konno, Tomonobu; Wang, Shengyue; Li, Xuan; Ji, Zai-Si; Zhao, Guoping

2011-01-01

Lactobacillus delbrueckii subsp. bulgaricus (Lb. bulgaricus) is an important species of Lactic Acid Bacteria (LAB) used for cheese and yogurt fermentation. The genome of Lb. bulgaricus 2038, an industrial strain mainly used for yogurt production, was completely sequenced and compared against the other two ATCC collection strains of the same subspecies. Specific physiological properties of strain 2038, such as lysine biosynthesis, formate production, aspartate-related carbon-skeleton intermediate metabolism, unique EPS synthesis and efficient DNA restriction/modification systems, are all different from those of the collection strains that might benefit the industrial production of yogurt. Other common features shared by Lb. bulgaricus strains, such as efficient protocooperation with Streptococcus thermophilus and lactate production as well as well-equipped stress tolerance mechanisms may account for it being selected originally for yogurt fermentation industry. Multiple lines of evidence suggested that Lb. bulgaricus 2038 was genetically closer to the common ancestor of the subspecies than the other two sequenced collection strains, probably due to a strict industrial maintenance process for strain 2038 that might have halted its genome decay and sustained a gene network suitable for large scale yogurt production. PMID:21264216

Sugar utilization patterns and respiro-fermentative metabolism in the baker’s yeast Torulaspora delbrueckii

OpenAIRE

Araújo, Cecília Alves; Pacheco, A.; Almeida, M. J.; Martins, I. Spencer; Leão, Cecília; Sousa, M. J.

2007-01-01

The highly osmo- and cryotolerant yeast species Torulaspora delbrueckii is an important case study among the non-Saccharomyces yeast species. The strain T delbrueckii PYCC 532 1, isolated from traditional corn and rye bread dough in northern Portugal, is considered particularly interesting for the baking industry. This paper reports the sugar utilization patterns of this strain, using media with glucose, maltose and sucrose, alone or in mixtures. Kinetics of growth, biomass and ethanol yields...

Impact of bile salt adaptation of Lactobacillus delbrueckii subsp. lactis 200 on its interaction capacity with the gut.

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Burns, Patricia; Reinheimer, Jorge; Vinderola, Gabriel

2011-10-01

In a previous work, bile-salt-resistant derivatives were obtained from non-intestinal lactobacilli. The aim of this work was to investigate the impact of bile adaptation of Lactobacillus delbrueckii subsp. lactis 200 on morphology, surface properties, in vivo interaction capacity with the gut and ability to activate the gut immune response. Electron microscopy studies, growth kinetics in the presence of bovine and porcine bile, the capacity to deconjugate bile acids, hydrophobicity, autoaggregation and co-aggregation capacities were studied for the parental strain and its bile-resistant derivative in vitro. Additionally, survival in intestinal fluid, the interaction with the gut and the immunomodulating capacities were studied in mice. Bile salt adaptation conferred upon the adapted strain a higher capacity to withstand physiological concentrations of bile salts and greater survival capacity in intestinal fluid. However, bile salt exposure reduced cell hydrophobicity, autoaggregation and adhesion capacities, resulting in reduced persistence in the intestinal lumen and delayed capacity to activate the gut immune response. Insight into the effects of bile salts upon the interaction and immunomodulating capacity of lactobacilli with the gut is provided, relating in vitro and in vivo results. Copyright © 2011 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

KOMPOSISI KIMIAWI DAN KECERNAAN INVITRO SILASE HIJAUAN GEMBILINA (Gmelina arborea MENGGUNAKAN INOKULUM Lactobacillus collinoides DAN Lactobacillus delbrueckii

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Badat Muwakhid

2014-06-01

Full Text Available The purpose of this research is to know an effect of the lactate acid bacteria inoculants of toward Gmelina arborea forage as feeding material.The significance of this research is hopefully as direction and information about using Gmelina arborea forage effectively and efficiently. The research was experimental method by completely randomized design. In the type of inoculants treatment is Lactobacillus collinoides, Lactobacillus delbrueckii, the mixture (compounding between Lactobacillus collinoides, Lactobacillus delbrueckii 1:1, and giving treatment to the incubation length for about 2, 3, 5, 10, 15 and 21 days in the nested of bacterial types factorial. Each treatment is repeated for 3 times. The result showed that lactic acid bacteria inoculant affects affected to the content of NDF, ADF, cellulose, and affected in invitro dry matter digestibility (IVDMD and invitro organic matter digestibility (IVOMD of Gmelina arborea forage as well. The Lactobacillus delbrueckii inoculant is the most effective to defend the lost of NDF, ADF and cellulose, and to defend the decrease of IVDMD and IVOMD during ensilages. The bacterial inoculums Lactobacillus delbrueckii is able to accelerate quality reduction stagnation of NDF, ADF and cellulose, and IVDMD and IVOMD for five days, while others for ten days. It is suggested to obtain good forage ensiling in Gmelina arborea forage, it is better to use Lactobacillus delbrueckii inoculant.

In vitro evaluation of immunological properties of extracellular polysaccharides produced by Lactobacillus delbrueckii strains.

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Kishimoto, Mana; Nomoto, Ryohei; Osawa, Ro

2015-01-01

We investigated the variation in immunological properties of the extracellular polysaccharides (EPSs) produced by different Lactobacillus delbrueckii strains as well as that of their monosaccharide composition. The monosaccharide composition of each EPS produced by L. delbrueckii strains, as determined by thin layer chromatography (TLC), showed an appreciable variation in a strain-dependent manner, which could be broadly assigned to 4 TLC groups. Meanwhile, the immunological properties of the EPSs produced by 10 L. delbrueckii strains were evaluated in a semi-intestinal model using a Transwell co-culture system, which employed human intestinal epithelial Caco-2 cells on the apical side and murine macrophage RAW264.7 cells on the basolateral side. Each EPS was added to the apical side to allow direct contact with Caco-2 cells and incubated for 6 hr. After incubation, the amounts of TNF-α and several cytokines that had been released by either RAW264.7 or Caco-2 cells were then quantified by cytotoxic activity on L929 cells or the RT-PCR method. It was found that the EPS-stimulated RAW264.7 cells express different profiles of cytokine production via Caco-2 cells but that the profile difference could not be related to the above TLC grouping. The evidence suggests that the EPSs of L. delbrueckii strains are diverse not only in their biochemical structure but also in their immunological properties.

Identification of Lactobacillus spp. from broiler litter in Brazil Identificação de Lactobacillus spp. de cama de frango no Brasil

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Ronaldo S. Paço

2003-07-01

Full Text Available Lactobacillus spp. were identified in 100 broiler litter samples collected from different poultry-rearing regions in Brazil. Ten different Lactobacillus species were identified: L. plantarum, L.casei subsp. pesudoplantarum, L. delbrueckii subsp. delbrueckii, L. reuteri, L. murinus, L. agilis, L. delbrueckii subsp. lactis, L. salivarus subsp. salicinus, L. viridenscens and L. amylophilus.Foram identificadas cepas de Lactobacillus spp. de 100 amostras de camas de frango coletadas de diferentes regiões de produção avícola do Brasil. Foram isoladas dez espécies diferentes de Lactobacillus: L. plantarum, L. casei subsp. pseudoplantarum, L. delbrueckii subsp. delbrueckii, L. reuteri, L. murinus, L. agilis, L.delbrueckii subsp. lactis, L. salivarus subsp. salicinus, L. viridenscens, L. amylophilus.

Cloning of D-lactate dehydrogenase genes of Lactobacillus delbrueckii subsp. bulgaricus and their roles in D-lactic acid production.

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Huang, Yanna; You, Chunping; Liu, Zhenmin

2017-07-01

Lactobacillus delbrueckii subsp. bulgaricus is a heterogenous lactic acid bacterium that converts pyruvate mainly to D-lactic acid using D-lactate dehydrogenases (D-LDHs), whose functional properties remain poorly characterized. Here, the D-LDHs genes (ldb0101, ldb0813, ldb1010, ldb1147 and ldb2021) were cloned and overexpressed in Escherichia coli JM109 from an inducible pUC18 vector, respectively, and the resulting strains were compared in terms of D-lactic acid production. The strain expressing ldb0101 and ldb1010 gene individually produced more D-lactate than other three strains. Further study revealed that Ldb0101 activity was down-regulated by the oxygen and, therefore, achieved a highest titer of D-lactate (1.94 g/L) under anaerobic condition, and introduction of ldb1010 gene enhanced D-lactate formation (0.94 and 0.85 g/L, respectively) both in aerobic and anaerobic conditions due to a relatively stable q d-lactate . Our results suggested that the enzyme Ldb0101 and Ldb1010 played a role of more importance in D-lactate formation. To the best of our knowledge, we demonstrate for the first time the roles of different D-LDH homologs from L. bulgaricus in D-lactic acid production.

Protoplast formation and regeneration in Lactobacillus delbrueckii

OpenAIRE

Singhvi, Mamta; Joshi, Dipti; Gaikaiwari, Shalaka; Gokhale, Digambar V.

2010-01-01

Method for production and regeneration of Lactobacillus delbrueckii protoplasts are described. The protoplasts were obtained by treatment with a mixture of lysozyme and mutanolysin in protoplast buffer at pH 6.5 with different osmotic stabilizers. The protoplasts were regenerated on deMan, Rogosa and Sharpe (MRS) with various osmotic stabilizers. Maximum protoplast formation was obtained in protoplast buffer with sucrose as an osmotic stabilizer using a combination of lysozyme (1 mg/ml) and m...

Effects of new Torulaspora delbrueckii killer yeasts on the must fermentation kinetics and aroma compounds of white table wine

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Rocío eVelázquez

2015-11-01

Full Text Available Torulaspora delbrueckii is becoming widely recommended for improving some specific characteristics of wines. However, its impact on wine quality is still far from satisfactory at the winery level, mostly because it is easily replaced by S. cerevisiae-like yeasts during must fermentation. New T. delbrueckii killer strains were here isolated and selected for winemaking. They killed S. cerevisiae yeasts and were able to dominate and complete the fermentation of sterile grape must. Sequential yeast inoculation of non-sterile white must with T. delbrueckii followed by S. cerevisiae did not ensure T. delbrueckii dominance or wine quality improvement. Only a single initial must inoculation at high cell concentrations allowed the T. delbrueckii killer strains to dominate and complete the must fermentation to reach above 11% ethanol, but not the non-killer strains. None of the wines underwent malolactic fermentation as long as the must had low turbidity and pH. Although no statistically significant differences were found in the wine quality score, the S. cerevisiae-dominated wines were preferred over the T. delbrueckii-dominated ones because the former had high-intensity fresh fruit aromas while the latter had lower intensity, but nevertheless nice and unusual dried fruit/pastry aromas. Except for ethyl propanoate and 3-ethoxy-1-propanol, which were more abundant in the T. delbrueckii–dominated wines, most of the compounds with fresh fruit odour descriptors, including those with the greatest odour activity values (isoamyl acetate, ethyl hexanoate, and ethyl octanoate, were more abundant in the S. cerevisiae–dominated wines. The low relative concentrations of these fruity compounds made it possible to detect in the T. delbrueckii–dominated wines the low-relative-concentration compounds with dried fruit and pastry odours. An example was γ-ethoxy-butyrolactone which was significantly more abundant in these wines than in those dominated by S

Effects of new Torulaspora delbrueckii killer yeasts on the must fermentation kinetics and aroma compounds of white table wine

Science.gov (United States)

Velázquez, Rocío; Zamora, Emiliano; Álvarez, María L.; Hernández, Luis M.; Ramírez, Manuel

2015-01-01

Torulaspora delbrueckii is becoming widely recommended for improving some specific characteristics of wines. However, its impact on wine quality is still far from satisfactory at the winery level, mostly because it is easily replaced by Saccharomyces cerevisiae-like yeasts during must fermentation. New T. delbrueckii killer strains were here isolated and selected for winemaking. They killed S. cerevisiae yeasts and were able to dominate and complete the fermentation of sterile grape must. Sequential yeast inoculation of non-sterile white must with T. delbrueckii followed by S. cerevisiae did not ensure T. delbrueckii dominance or wine quality improvement. Only a single initial must inoculation at high cell concentrations allowed the T. delbrueckii killer strains to dominate and complete the must fermentation to reach above 11% ethanol, but not the non-killer strains. None of the wines underwent malolactic fermentation as long as the must had low turbidity and pH. Although no statistically significant differences were found in the wine quality score, the S. cerevisiae-dominated wines were preferred over the T. delbrueckii-dominated ones because the former had high-intensity fresh fruit aromas while the latter had lower intensity, but nevertheless nice and unusual dried fruit/pastry aromas. Except for ethyl propanoate and 3-ethoxy-1-propanol, which were more abundant in the T. delbrueckii–dominated wines, most of the compounds with fresh fruit odor descriptors, including those with the greatest odor activity values (isoamyl acetate, ethyl hexanoate, and ethyl octanoate), were more abundant in the S. cerevisiae–dominated wines. The low relative concentrations of these fruity compounds made it possible to detect in the T. delbrueckii–dominated wines the low-relative-concentration compounds with dried fruit and pastry odors. An example was γ-ethoxy-butyrolactone which was significantly more abundant in these wines than in those dominated by S. cerevisiae. PMID

Enhanced 3-sulfanylhexan-1-ol production in sequential mixed fermentation with Torulaspora delbrueckii/Saccharomyces cerevisiae reveals a situation of synergistic interaction between two industrial strains

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Philippe eRenault

2016-03-01

Full Text Available The aim of this work was to study the volatile thiol productions of 2 industrial strains of Torulaspora delbrueckii and Saccharomyces cerevisiae during alcoholic fermentation (AF of Sauvignon Blanc must. In order to evaluate the influence of the inoculation procedure, sequential and simultaneous mixed cultures were carried out and compared to pure cultures of T. delbrueckii and S. cerevisiae. The results confirmed the inability of T. delbrueckii to release 4-methyl-4-sulfanylpentan-2-one (4MSP and its low capacity to produce 3-sulfanylhexyl acetate (3SHA, as already reported in previous studies. A synergistic interaction was observed between the two species, resulting in higher levels of 3SH (3-sulfanylhexan-1-ol and its acetate when S. cerevisiae was inoculated 24 hours after T. delbrueckii, compared to the pure cultures. To elucidate the nature of the interactions between these 2 species, the yeast population kinetics were examined and monitored, as well as the production of 3SH, its acetate and their related non-odorous precursors: Glut-3SH (glutathionylated conjugate precursor and Cys-3SH (cysteinylated conjugate precursor. For the first time, it was suggested that, unlike, S. cerevisiae, which is able to metabolize the two precursor forms, T. delbrueckii was only able to metabolize the glutathionylated precursor. Consequently, the presence of T. delbrueckii during mixed fermentation led to an increase in Glut-3SH degradation and Cys-3SH production. This overproduction was dependent on the T. delbrueckii biomass. In sequential culture, thus favouring T. delbrueckii development, the higher availability of Cys-3SH throughout AF (alcoholic fermentation resulted in more abundant 3SH and 3SHA production by S. cerevisiae

Enhanced 3-Sulfanylhexan-1-ol Production in Sequential Mixed Fermentation with Torulaspora delbrueckii/Saccharomyces cerevisiae Reveals a Situation of Synergistic Interaction between Two Industrial Strains.

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Renault, Philippe; Coulon, Joana; Moine, Virginie; Thibon, Cécile; Bely, Marina

2016-01-01

The aim of this work was to study the volatile thiol productions of two industrial strains of Torulaspora delbrueckii and Saccharomyces cerevisiae during alcoholic fermentation (AF) of Sauvignon Blanc must. In order to evaluate the influence of the inoculation procedure, sequential and simultaneous mixed cultures were carried out and compared to pure cultures of T. delbrueckii and S. cerevisiae. The results confirmed the inability of T. delbrueckii to release 4-methyl-4-sulfanylpentan-2-one (4MSP) and its low capacity to produce 3-sulfanylhexyl acetate (3SHA), as already reported in previous studies. A synergistic interaction was observed between the two species, resulting in higher levels of 3SH (3-sulfanylhexan-1-ol) and its acetate when S. cerevisiae was inoculated 24 h after T. delbrueckii, compared to the pure cultures. To elucidate the nature of the interactions between these two species, the yeast population kinetics were examined and monitored, as well as the production of 3SH, its acetate and their related non-odorous precursors: Glut-3SH (glutathionylated conjugate precursor) and Cys-3SH (cysteinylated conjugate precursor). For the first time, it was suggested that, unlike S. cerevisiae, which is able to metabolize the two precursor forms, T. delbrueckii was only able to metabolize the glutathionylated precursor. Consequently, the presence of T. delbrueckii during mixed fermentation led to an increase in Glut-3SH degradation and Cys-3SH production. This overproduction was dependent on the T. delbrueckii biomass. In sequential culture, thus favoring T. delbrueckii development, the higher availability of Cys-3SH throughout AF resulted in more abundant 3SH and 3SHA production by S. cerevisiae.

Effects of Lactobacillus delbrueckii on immune response, disease resistance against Aeromonas hydrophila, antioxidant capability and growth performance of Cyprinus carpio Huanghe var.

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Zhang, Chun-Nuan; Zhang, Ji-Liang; Guan, Wen-Chao; Zhang, Xiao-Fei; Guan, Su-Hua; Zeng, Qing-Hui; Cheng, Gao-Feng; Cui, Wei

2017-09-01

The aim of the present study was to investigate effects of dietary Lactobacillus delbrueckii (L. delbrueckii) on immune response, disease resistance against Aeromonas hydrophila (A. hydrophila), antioxidant capability and growth performance of Cyprinus carpio Huanghe var. 450 fish (mean weight of 1.05 ± 0.03 g) were randomly distributed into five groups that fed diets containing different levels of L. delbrueckii (0, 1 × 10 5 , 1 × 10 6 , 1 × 10 7 and 1 × 10 8  CFU g -1 ) for 8 weeks. The results showed that intestinal immune parameters such as lysozyme, acid phosphatase, and myeloperoxidase activities, immunoglobulin M content, and the survival rate were improved in fish fed with 1 × 10 6 and 1 × 10 7  CFU g -1 L. delbrueckii. In addition, 1 × 10 7  CFU g -1 L. delbrueckii supplementation down-regulated mRNA levels of TNF-α, IL-8, IL-1β and NF-κBp65, and up-regulated IL-10 and TGF-β mRNA levels in the intestine. The survival rate was significantly (P < 0.05) higher (68.33%) in fish fed 1 × 10 6  CFU g -1 L. delbrueckii than the control diet-fed group (40%) after challenge by A. hydrophila. Fish fed with diet containing 1 × 10 6  CFU g -1 L. delbrueckii showed higher antioxidant enzyme activities such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX), and total antioxidant capacity (T-AOC) and lower MDA concentrations than those of the control group (P < 0.05). The relative gene expression (SOD, CAT, GPX) showed the same trend with their activities. In addition, the growth performance was significantly improved in fish fed with the diet containing 1 × 10 6 and 1 × 10 7  CFU g -1 L. delbrueckii (P < 0.05). These results demonstrated that dietary optimal levels of L. delbrueckii enhanced immunity, disease resistance against A. hydrophila antioxidant capability and growth performance in Cyprinus carpio Huanghe var. Copyright © 2017 Elsevier Ltd. All rights reserved.

Increased expression of clp genes in Lactobacillus delbrueckii UFV H2b20 exposed to acid stress and bile salts.

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Ferreira, A B; De Oliveira, M N V; Freitas, F S; Alfenas-Zerbini, P; Da Silva, D F; De Queiroz, M V; Borges, A C; De Moraes, C A

2013-12-01

The ability to survive in harsh environments is an important criterion to select potential probiotics strains. The objective of this study was to identify and carry out phylogenetic and expression analysis by quantitative real-time PCR of the clpP, clpE, clpL and clpX genes in the probiotic strain Lactobacillus delbrueckii UFV H2b20 exposed to the conditions prevailing in the gastrointestinal tract (GIT). Phylogenetic trees reconstructed by Bayesian inference showed that the L. delbrueckii UFV H2b20 clpP, clpL and clpE genes and the ones from L. delbrueckii ATCC 11842 were grouped. The exposure of cells to MRS broth of pH 3.5 for 30 and 60 min resulted in an increased expression of the four genes. Exposure of the L. delbrueckii UFV H2b20 cells for 30 and 60 min to MRS broth containing 0.1% bile salts increased the expression of the clpP and clpE genes, while the expression level of the clpL and clpX genes increased only after 30 min of exposure. The involvement of the studied genes in the responses to acid stress and bile salts suggests a possible central role of these genes in the survival of L. delbrueckii UFV H2b20 during the passage through the GIT, a characteristic necessary for probiotic strains.

The extracellular phage-host interactions involved in the bacteriophage LL-H infection of Lactobacillus delbrueckii ssp. lactis ATCC 15808.

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Munsch-Alatossava, Patricia; Alatossava, Tapani

2013-12-24

The complete genome sequence of Lactobacillus bacteriophage LL-H was determined in 1996. Accordingly, LL-H has been used as a model phage for the infection of dairy Lactobacillus, specifically for thermophilic Lactobacillus delbrueckii ssp. lactis host strains, such as ATCC 15808. One of the major goals of phage LL-H research consisted of the characterization of the first phage-host interactions at the level of phage adsorption and phage DNA injection steps to determine effective and practical methods to minimize the risks associated with the appearance and attack of phages in the manufacture of yogurt, and Swiss or Italian hard type cheeses, which typically use thermophilic lactic acid bacteria starter cultures containing L. delbrueckii strains among others. This mini review article summarizes the present data concerning (i) the special features, particle structure, and components of phage LL-H and (ii) the structure and properties of lipoteichoic acids (LTAs), which are the phage LL-H receptor components of L. delbrueckii ssp. lactis host strains. Moreover, a model of the first, extracellular, phage-host interactions for the infection of L. delbrueckii ssp. lactis ATCC 15808 by phage LL-H is presented and further discussed.

The extracellular phage-host interactions involved in the bacteriophage LL-H infection of Lactobacillus delbrueckii ssp. lactis ATCC 15808

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Patricia eMunsch-Alatossava

2013-12-01

Full Text Available The complete genome sequence of Lactobacillus bacteriophage LL-H was determined in 1996. Accordingly, LL-H has been used as a model phage for the infection of dairy Lactobacillus, specifically for thermophilic Lb. delbrueckii ssp. lactis host strains, such as ATCC 15808. One of the major goals of phage LL-H research consisted of the characterization of the the first phage-host interactions at the level of phage adsorption and phage DNA injection steps to determine effective and practical methods to minimise the risks associated with the appearance and attack of phages in the manufacture of yoghurt, and Swiss or Italian type hard cheeses, which typically use thermophilic LAB starter cultures containing Lb. delbrueckii strains among others. This mini review article summarises the present data concerning (i the special features, particle structure and components of phage LL-H and (ii the structure and properties of lipoteichoic acids (LTAs, which are the phage LL-H receptor components of Lb. delbrueckii ssp. lactis host strains. Moreover, a model of the first, extracellular, phage-host interactions for the infection of Lb. delbrueckii ssp. lactis ATCC 15808 by phage LL-H is presented and further discussed.

Monoassociation with probiotic Lactobacillus delbrueckii UFV-H2b20 stimulates the immune system and protects germfree mice against Listeria monocytogenes infection.

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dos Santos, Liliane Martins; Santos, Mônica Morais; de Souza Silva, Humberto Pereira; Arantes, Rosa Maria Esteves; Nicoli, Jacques Robert; Vieira, Leda Quercia

2011-02-01

In the present study, we investigated the protective effects of Lactobacillus delbrueckii UFV-H2b20 on the resistance to Listeria monocytogenes infection in gnotobiotic mice. Germfree mice or monoassociated mice were infected with L. monocytogenes, and the microbiological and immunological responses were evaluated after 1, 3, and 5 days of infection. Monoassociation with L. delbrueckii was capable of protecting mice against death caused by L. monocytogenes and induced a faster clearance of the bacteria in the liver, spleen, and peritoneal cavity at days 1, 3, and 5 post-infection. Also, monoassociated mice displayed less liver injury than germfree mice. The production of TNF-α in the serum, peritoneal cavity, and gut was augmented in monoassociated mice. Likewise, the levels of IFN-γ found on supernatants of spleen cells cultures were higher after the monoassociation. In addition, increased production of nitric oxide in peritoneal cell cultures supernatants and in serum was observed in mice that received L. delbrueckii. The monoassociation with L. delbrueckii induced higher production of IL-10 in the mucosal immune system. We conclude that monoassociation with L. delbrueckii UFV-H2b20 protects mice from death caused by L. monocytogenes infection by favoring effector responses while preventing their immunopathological consequences.

Effect of Formic Acid on Exopolysaccharide Production in Skim Milk Fermentation by Lactobacillus delbrueckii subsp. bulgaricus OLL1073R-1.

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Nishimura, Junko; Kawai, Yasushi; Aritomo, Ryota; Ito, Yoshiyuki; Makino, Seiya; Ikegami, Shuji; Isogai, Emiko; Saito, Tadao

2013-01-01

In yogurt, the formation of formate by Streptococcus thermophilus stimulates the activity of Lactobacillus delbrueckii subsp. bulgaricus (L. bulgaricus). However, there have been no reports how formic acid acts on the exopolysaccharide (EPS) production of L. bulgaricus. Here, the effect of formate on the EPS production in skim milk by L. bulgaricus OLL1073R-1 was investigated. After incubation for 24 hr with 100 mg/l formate, cell proliferation and lactic acid production were accelerated. The viable and total cell numbers were increased about ten- and four-fold, respectively. The amount of EPS in culture with formate (~116 µg/ml) was also four-fold greater than that of the control (~27 µg/ml). Although elongation of cells was observed at 6 hr of cultivation in both cultures, cells cultivated with formate returned to a normal shape after incubation for 24 hr. The sensitivity to cell wall hydrolase and composition of surface layer proteins, as well as the cell membrane fatty acid composition of L. bulgaricus OLL1073R-1, were not influenced by formate. However, differences were observed in intracellular fatty acid compositions and sensitivity to antibiotics. Cell length and surface damage returned to normal in cultures with formate. These observations suggest that formic acid is necessary for normal cell growth of L. bulgaricus OLL1073R-1 and higher EPS production.

Osmotolerance and leavening ability in sweet and frozen sweet dough. Comparative analysis between Torulaspora delbrueckii and Saccharomyces cerevisiae baker's yeast strains.

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Hernandez-Lopez, M J; Prieto, J A; Randez-Gil, F

2003-01-01

The response of Saccharomyces cerevisiae and freeze-tolerant Torulaspora delbrueckii strains to osmotic stress and their CO2 production capacity in sweet and frozen-sweet dough has been examined. T. delbrueckii strains, IGC5321 and IGC5323 showed higher leavening ability than Saccharomyces, specially after exposure to hyperosmotic stress of bread dough containing 20% sucrose and 2% salt added. In addition, Torulaspora and especially T. delbrueckii IGC5321 exhibited no loss of CO2 production capacity during freeze-thaw stress. Overall, these results appeared to indicate that Torulaspora cells are more tolerant than Saccharomyces to osmotic stress of bread dough. This trait correlated with a low invertase activity, a slow rate of trehalose mobilisation and the ability to respond rapidly to osmotic stress. Growth behaviour on high osmotic synthetic media was also examined. Cells of the IGC5321 strain showed intrinsic osmotolerance and ion toxicity resistance. However, T. delbrueckii IGC5323 exhibited a clear phenotype of osmosensitivity. Hence, this characteristic may not be essential or the only determinant for leavening ability in salted high-sugar dough.

Effect of Lactobacillus delbrueckii on cholesterol metabolism in germ-free mice and on atherogenesis in apolipoprotein E knock-out mice

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Portugal L.R.

2006-01-01

Full Text Available Elevated blood cholesterol is an important risk factor associated with atherosclerosis and coronary heart disease. Several studies have reported a decrease in serum cholesterol during the consumption of large doses of fermented dairy products or lactobacillus strains. The proposed mechanism for this effect is the removal or assimilation of intestinal cholesterol by the bacteria, reducing cholesterol absorption. Although this effect was demonstrated in vitro, its relevance in vivo is still controversial. Furthermore, few studies have investigated the role of lactobacilli in atherogenesis. The aim of the present study was to determine the effect of Lactobacillus delbrueckii on cholesterol metabolism in germ-free mice and the possible hypocholesterolemic and antiatherogenic action of these bacteria using atherosclerosis-prone apolipoprotein E (apo E knock-out (KO mice. For this purpose, Swiss/NIH germ-free mice were monoassociated with L. delbrueckii and fed a hypercholesterolemic diet for four weeks. In addition, apo E KO mice were fed a normal chow diet and treated with L. delbrueckii for 6 weeks. There was a reduction in cholesterol excretion in germ-free mice, which was not associated with changes in blood or liver cholesterol concentration. In apo E KO mice, no effect of L. delbrueckii was detected in blood, liver or fecal cholesterol. The atherosclerotic lesion in the aorta was also similar in mice receiving or not these bacteria. In conclusion, these results suggest that, although L. delbrueckii treatment was able to reduce cholesterol excretion in germ-free mice, no hypocholesterolemic or antiatherogenic effect was observed in apo E KO mice.

Molecular discrimination of lactobacilli used as starter and probiotic cultures by amplified ribosomal DNA restriction analysis.

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Roy, D; Sirois, S; Vincent, D

2001-04-01

Lactic acid bacteria such as Lactobacillus helveticus, L. delbrueckii subsp. delbrueckii, L. delbrueckii subsp. lactis, L. delbrueckii subsp. bulgaricus, L. acidophilus, and L. casei related taxa which are widely used as starter or probiotic cultures can be identified by amplified ribosomal DNA restriction analysis (ARDRA). The genetic discrimination of the related species belonging to these groups was first obtained by PCR amplifications by using group-specific or species-specific 16S rDNA primers. The numerical analysis of the ARDRA patterns obtained by using CfoI, HinfI, Tru9I, and ScrFI was an efficient typing tool for identification of species of the L. acidophilus and L. casei complex. ARDRA by using CfoI was a reliable method for differentiation of L. delbrueckii subsp. bulgaricus and L. delbrueckii subsp. lactis. Finally, strains ATCC 393 and ATCC 15820 exhibited unique ARDRA patterns with CfoI and Tru9I restriction enzymes as compared with the other strains of L. casei, L. paracasei, and L. rhamnosus.

Lactobacillus delbrueckii UFV-H2b20 induces type 1 cytokine production by mouse cells in vitro and in vivo

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E. Neumann

2009-04-01

Full Text Available Lactobacillus delbrueckii UFV-H2b20 has been shown to increase clearance of bacteria injected into the blood of germ-free mice. Moreover, it induces the production of type 1 cytokines by human peripheral mononuclear cells. The objective of the present study was to investigate the production of inflammatory cytokines [interleukin-12 (IL-12 p40, tumor necrosis factor-α (TNF-α, and interferon-γ (IFN-γ] triggered in vitro by live, heat-killed or lysozyme-treated L. delbrueckii UFV-H2b20 and in vivo by a live preparation. Germ-free, L. delbrueckii-monoassociated and lipopolysaccharide (LPS-resistant C3H/HeJ mice were used as experimental models. UFV-H2b20 induced the production of IL-12 p40 and TNF-α by peritoneal cells and IFN-γ by spleen cells from germ-free or monoassociated Swiss/NIH mice and LPS-hyporesponsive mice (around 40 ng/mL for IL-12 p40, 200 pg/mL for TNF-α and 10 ng/mL for IFN-γ. Heat treatment of L. delbrueckii did not affect the production of these cytokines. Lysozyme treatment decreased IL-12 p40 production by peritoneal cells from C3H/HeJ mice, but did not affect TNF-α production by these cells or IFN-γ production by spleen cells from the same mouse strain. TNF-α production by peritoneal cells from Swiss/NIH L. delbrueckii-monoassociated mice was inhibited by lysozyme treatment. When testing IL-12 p40 and IFN-γ levels in sera from germ-free or monoassociated Swiss/NIH mice systemically challenged with Escherichia coli we observed that IL-12 p40 was produced at marginally higher levels by monoassociated mice than by germ-free mice (40 vs 60 ng/mL, but IFN-γ was produced earlier and at higher levels by monoassociated mice (monoassociated 4 and 14 ng/mL 4 and 8 h after infection, germfree 0 and 7.5 ng/mL at the same times. These results show that L. delbrueckii UFV-H2b20 stimulates the production of type 1 cytokines in vitro and in vivo, therefore suggesting that L. delbrueckii might have adjuvant properties in infection

The Baseplate of Lactobacillus delbrueckii Bacteriophage Ld17 Harbors a Glycerophosphodiesterase.

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Cornelissen, Anneleen; Sadovskaya, Irina; Vinogradov, Evgeny; Blangy, Stéphanie; Spinelli, Silvia; Casey, Eoghan; Mahony, Jennifer; Noben, Jean-Paul; Dal Bello, Fabio; Cambillau, Christian; van Sinderen, Douwe

2016-08-05

Glycerophosphodiester phosphodiesterases (GDPDs; EC 3.1.4.46) typically hydrolyze glycerophosphodiesters to sn-glycerol 3-phosphate (Gro3P) and their corresponding alcohol during patho/physiological processes in bacteria and eukaryotes. GDPD(-like) domains were identified in the structural particle of bacterial viruses (bacteriophages) specifically infecting Gram-positive bacteria. The GDPD of phage 17 (Ld17; GDPDLd17), representative of the group b Lactobacillus delbrueckii subsp. bulgaricus (Ldb)-infecting bacteriophages, was shown to hydrolyze, besides the simple glycerophosphodiester, two complex surface-associated carbohydrates of the Ldb17 cell envelope: the Gro3P decoration of the major surface polysaccharide d-galactan and the oligo(glycerol phosphate) backbone of the partially glycosylated cell wall teichoic acid, a minor Ldb17 cell envelope component. Degradation of cell wall teichoic acid occurs according to an exolytic mechanism, and Gro3P substitution is presumed to be inhibitory for GDPDLd17 activity. The presence of the GDPDLd17 homotrimer in the viral baseplate structure involved in phage-host interaction together with the dependence of native GDPD activity, adsorption, and efficiency of plating of Ca(2+) ions supports a role for GDPDLd17 activity during phage adsorption and/or phage genome injection. In contrast to GDPDLd17, we could not identify any enzymatic activity for the GDPD-like domain in the neck passage structure of phage 340, a 936-type Lactococcus lactis subsp. lactis bacteriophage. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

Survival of Lactobacillus delbrueckii UFV H2b20 in fermented milk under simulated gastric and intestinal conditions.

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da Conceição, L L; Leandro, E S; Freitas, F S; de Oliveira, M N V; Ferreira-Machado, A B; Borges, A C; de Moraes, C A

2013-09-01

The survival of Lactobacillus delbrueckii UFV H2b20 was assessed in fermented milk, both during the storage period and after exposure to simulated gastric and intestinal juices, as well the detection of the gene fbpA involved in adherence to human gastrointestinal tract. L. delbrueckii UFV H2b20 remained stable and viable for 28 days under refrigerated storage conditions. After one day of storage, that strain exhibited a one-log population reduction following exposure in tandem to simulated gastric and intestinal juices. After 14 days of storage, a two-log reduction was observed following 90 min of exposure to the simulated gastric conditions. However, the strain did not survive following exposure to the simulated intestinal juice. The observed tolerance to storage conditions and resistance to the simulated gastric and intestinal conditions confirm the potential use of L. delbrueckii UFV H2b20 as a probiotic, which is further reinforced by the detection of fbpA in this strain.

In Vitro and In Vivo Evaluation of Lactobacillus delbrueckii subsp. bulgaricus KLDS1.0207 for the Alleviative Effect on Lead Toxicity.

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Li, Bailiang; Jin, Da; Yu, Shangfu; Etareri Evivie, Smith; Muhammad, Zafarullah; Huo, Guicheng; Liu, Fei

2017-08-08

Lead (Pb) is a toxic contaminating heavy metal that can cause a variety of hazardous effects to both humans and animals. In the present study, Lactobacillus delbrueckii subsp. bulgaricus KLDS1.0207 ( L. bulgaricus KLDS1.0207), which has a remarkable Pb binding capacity and Pb tolerance, was selected for further study. It was observed that the thermodynamic and kinetic model of L. bulgaricus KLDS1.0207 Pb binding respectively fit with the Langmuir-Freundlich model and the pseudo second-order kinetic model. Scanning electron microscopy and energy dispersive spectroscopy analysis disclosed that the cell surfaces were covered with Pb and that carbon and oxygen elements were chiefly involved in Pb binding. Combined with Fourier transform infrared spectroscopy analysis, it was revealed that the carboxyl, phosphoryl, hydroxyl, amino and amide groups were the main functional groups involved in the Pb adsorption. The protective effects of L. bulgaricus KLDS1.0207 against acute Pb toxicity in mice was evaluated by prevention and therapy groups, the results in vivo showed that L. bulgaricus KLDS1.0207 treatment could reduce mortality rates, effectively increase Pb levels in the feces, alleviate tissue Pb enrichment, improve the antioxidant index in the liver and kidney, and relieve renal pathological damage. Our findings show that L. bulgaricus KLDS1.0207 can be used as a potential probiotic against acute Pb toxicity.

In vivo study of the survival of Lactobacillus delbruecki subsp. bulgaricus CECT 4005T and Streptococcus thermophilus CECT 801 by DVC-FISH after consumption of fermented milk.

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García-Hernández, J; Moreno, Y; Chuan, C; Hernández, M

2012-10-01

Direct Viable Count (DVC) method has been recently combined with fluorescent in situ hybridization (FISH) for the specific detection of viable cells of Lactobacillus delbrueckii subsp. bulgaricus CECT 4005T and Streptococcus thermophilus CECT 801. This method has been used to determine their in vitro viability to gastrointestinal juices, being the resistance of L. delbrueckii subsp. bulgaricus and S. thermophilus 26.2% and 9.2%, respectively. On the other hand, an in vivo study has been carried out with the application of this technique for their detection in human feces, after consuming fermented milk. Cells of L. delbrueckii subsp. bulgaricus CECT 4005T were not detected, whereas viable cells of S. thermophilus CECT 801 were detected in a number higher than 10(3) cells per gram in a 30% of the samples after 4 wk of consumption. DVC-FISH is a quick and culture-independent useful method, which has been applied for the 1st time in an in vivo survival study of LAB. © 2012 Institute of Food Technologists®

Biophysical characterization of the Lactobacillus delbrueckii subsp. bulgaricus membrane during cold and osmotic stress and its relevance for cryopreservation.

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Meneghel, Julie; Passot, Stéphanie; Dupont, Sébastien; Fonseca, Fernanda

2017-02-01

Freezing lactic acid bacteria often leads to cell death and loss of technological properties. Our objective was to provide an in-depth characterization of the biophysical properties of the Lactobacillus delbrueckii subsp. bulgaricus membrane in relation to its freeze resistance. Freezing was represented as a combination of cold and osmotic stress. This work investigated the relative incidence of increasing sucrose concentrations coupled or not with subzero temperatures without ice nucleation on the biological and biophysical responses of two strains with different membrane fatty acid compositions and freeze resistances. Following exposure of bacterial cells to the highest sucrose concentration, the sensitive strain exhibited a survival rate of less than 10 % and 5 h of acidifying activity loss. Similar biological activity losses were observed upon freeze-thawing and after osmotic treatment for each strain thus highlighting osmotic stress as the main source of cryoinjury. The direct measurement of membrane fluidity by fluorescence anisotropy was linked to membrane lipid organization characterized by FTIR spectroscopy. Both approaches made it possible to investigate the specific contributions of the membrane core and the bilayer external surface to cell degradation caused by cold and osmotic stress. Cold-induced membrane rigidification had no significant implication on bacterial freeze-thaw resistance. Interactions between extracellular sucrose and membrane phospholipid headgroups under osmotic stress were also observed. Such interactions were more evident in the sensitive strain and when increasing sucrose concentration, thus suggesting membrane permeabilization. The relevance of biophysical properties for elucidating mechanisms of cryoinjury and cryoprotection is discussed.

Effect of sequential inoculation (Torulaspora delbrueckii/Saccharomyces cerevisiae in the first fermentation on the foam properties of sparkling wine (Cava

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Medina-Trujillo Laura

2016-01-01

Full Text Available In a previous study we reported that sequential inoculation of Torulaspora delbrueckii and Saccharomyces cerevisiae during the first fermentation increased the protein concentration and improved the foaming properties of a base wine. Since effervescence and foam of sparkling wines are key quality factors, the interest of this practice for sparkling wine industry is obvious. In this paper we study whether the foaming properties of the sparkling wines produced from the base wines obtained by sequential inoculation with T. delbrueckii and S. cerevisiae remains better than those of their controls produced from base wines fermented only with S. cerevisiae. The obtained results confirmed that sequential inoculation in the production of the base wine originated sparkling wines with significantly higher maximum heights of foam than conventional inoculation, probably because autolysis of the T. delbrueckii cells in the base wine released higher amounts of proteins, especially of the low molecular weight fraction.

Characterization of C-S lyase from Lactobacillus delbrueckii subsp. bulgaricus ATCC BAA-365 and its potential role in food flavour applications.

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Allegrini, Alessandra; Astegno, Alessandra; La Verde, Valentina; Dominici, Paola

2017-04-01

Volatile thiols have substantial impact on the aroma of many beverages and foods. Thus, the control of their formation, which has been linked to C-S lyase enzymatic activities, is of great significance in industrial applications involving food flavours. Herein, we have carried out a spectroscopic and functional characterization of a putative pyridoxal 5'-phosphate (PLP)-dependent C-S lyase from the lactic acid bacterium Lactobacillus delbrueckii subsp. bulgaricus ATCC BAA-365 (LDB C-S lyase). Recombinant LDB C-S lyase exists as a tetramer in solution and shows spectral properties of enzymes containing PLP as cofactor. The enzyme has a broad substrate specificity toward sulphur-containing amino acids with aminoethyl-L-cysteine and L-cystine being the most effective substrates over L-cysteine and L-cystathionine. Notably, the protein also reveals cysteine-S-conjugate β-lyase activity in vitro, and is able to cleave a cysteinylated substrate precursor into the corresponding flavour-contributing thiol, with a catalytic efficiency higher than L-cystathionine. Contrary to similar enzymes of other lactic acid bacteria however, LDB C-S lyase is not capable of α,γ-elimination activity towards L-methionine to produce methanethiol, which is a significant compound in flavour development. Based on our results, future developments can be expected regarding the flavour-forming potential of Lactobacillus C-S lyase and its use in enhancing food flavours. © The Authors 2017. Published by Oxford University Press on behalf of the Japanese Biochemical Society. All rights reserved.

Effects of long-term intake of a yogurt fermented with Lactobacillus delbrueckii subsp. bulgaricus 2038 and Streptococcus thermophilus 1131 on mice.

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Usui, Yuki; Kimura, Yasumasa; Satoh, Takeshi; Takemura, Naoki; Ouchi, Yasuo; Ohmiya, Hiroko; Kobayashi, Kyosuke; Suzuki, Hiromi; Koyama, Satomi; Hagiwara, Satoko; Tanaka, Hirotoshi; Imoto, Seiya; Eberl, Gérard; Asami, Yukio; Fujimoto, Kosuke; Uematsu, Satoshi

2018-05-15

The gut is an extremely complicated ecosystem where microorganisms, nutrients and host cells interact vigorously. Although the function of the intestine and its barrier system weakens with age, some probiotics can potentially prevent age-related intestinal dysfunction. Lactobacillus delbrueckii subsp. bulgaricus 2038 and Streptococcus thermophilus 1131, which are the constituents of LB81 yogurt, are representative probiotics. However, it is unclear whether their long-term intake has a beneficial influence on systemic function. Here, we examined the gut microbiome, fecal metabolites and gene expression profiles of various organs in mice. Although age-related alterations were apparent in them, long-term LB81 yogurt intake led to an increased Bacteroidetes to Firmicutes ratio and elevated abundance of the bacterial family S24-7 (Bacteroidetes), which is known to be associated with butyrate and propanoate production. According to our fecal metabolite analysis to detect enrichment, long-term LB81 yogurt intake altered the intestinal metabolic pathways associated with propanoate and butanoate in the mice. Gene ontology analysis also revealed that long-term LB81 yogurt intake influenced many physiological functions related to the defense response. The profiles of various genes associated with antimicrobial peptides-, tight junctions-, adherens junctions- and mucus-associated intestinal barrier functions were also drastically altered in the LB81 yogurt-fed mice. Thus, long-term intake of LB81 yogurt has the potential to maintain systemic homeostasis, such as the gut barrier function, by controlling the intestinal microbiome and its metabolites.

Genome Sequence of Australian Indigenous Wine Yeast Torulaspora delbrueckii COFT1 Using Nanopore Sequencing.

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Tondini, Federico; Jiranek, Vladimir; Grbin, Paul R; Onetto, Cristobal A

2018-04-26

Here, we report the first sequenced genome of an indigenous Australian wine isolate of Torulaspora delbrueckii using the Oxford Nanopore MinION and Illumina HiSeq sequencing platforms. The genome size is 9.4 Mb and contains 4,831 genes. Copyright © 2018 Tondini et al.

Lactobacillus delbrueckii ssp. lactis and ssp. bulgaricus: a chronicle of evolution in action.

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El Kafsi, Hela; Binesse, Johan; Loux, Valentin; Buratti, Julien; Boudebbouze, Samira; Dervyn, Rozenn; Kennedy, Sean; Galleron, Nathalie; Quinquis, Benoît; Batto, Jean-Michel; Moumen, Bouziane; Maguin, Emmanuelle; van de Guchte, Maarten

2014-05-28

Lactobacillus delbrueckii ssp. lactis and ssp. bulgaricus are lactic acid producing bacteria that are largely used in dairy industries, notably in cheese-making and yogurt production. An earlier in-depth study of the first completely sequenced ssp. bulgaricus genome revealed the characteristics of a genome in an active phase of rapid evolution, in what appears to be an adaptation to the milk environment. Here we examine for the first time if the same conclusions apply to the ssp. lactis, and discuss intra- and inter-subspecies genomic diversity in the context of evolutionary adaptation. Both L. delbrueckii ssp. show the signs of reductive evolution through the elimination of superfluous genes, thereby limiting their carbohydrate metabolic capacities and amino acid biosynthesis potential. In the ssp. lactis this reductive evolution has gone less far than in the ssp. bulgaricus. Consequently, the ssp. lactis retained more extended carbohydrate metabolizing capabilities than the ssp. bulgaricus but, due to high intra-subspecies diversity, very few carbohydrate substrates, if any, allow a reliable distinction of the two ssp. We further show that one of the most important traits, lactose fermentation, of one of the economically most important dairy bacteria, L. delbruecki ssp. bulgaricus, relies on horizontally acquired rather than deep ancestral genes. In this sense this bacterium may thus be regarded as a natural GMO avant la lettre. The dairy lactic acid producing bacteria L. delbrueckii ssp. lactis and ssp. bulgaricus appear to represent different points on the same evolutionary track of adaptation to the milk environment through the loss of superfluous functions and the acquisition of functions that allow an optimized utilization of milk resources, where the ssp. bulgaricus has progressed further away from the common ancestor.

Two Novel Strains of Torulaspora delbrueckii Isolated from the Honey Bee Microbiome and Their Use in Honey Fermentation

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Joseph P. Barry

2018-03-01

Full Text Available Yeasts are ubiquitous microbes found in virtually all environments. Many yeast species can ferment sugar into ethanol and CO2, and humans have taken advantage of these characteristics to produce fermented beverages for thousands of years. As a naturally abundant source of fermentable sugar, honey has had a central role in such fermentations since Neolithic times. However, as beverage fermentation has become industrialized, the processes have been streamlined, including the narrow and almost exclusive usage of yeasts in the genus Saccharomyces for fermentation. We set out to identify wild honey- or honey-bee-related yeasts that can be used in honey fermentation. Here, we isolated two strains of Torulaspora delbrueckii from the gut of a locally collected honey bee. Both strains were able to ferment honey sugar into mead but failed to metabolize more than a modest amount of wort sugar in trial beer fermentations. Further, the meads fermented by the T. delbrueckii strains displayed better sensory characteristics than mead fermented by a champagne yeast. The combination of T. delbrueckii and champagne yeast strains was also able to rapidly ferment honey at an industrial scale. Thus, wild yeasts represent a largely untapped reservoir for the introduction of desirable sensory characteristics in fermented beverages such as mead.

An operon encoding three glycolytic enzymes in Lactobacillus delbrueckii subsp. bulgaricus: glyceraldehyde-3-phosphate dehydrogenase, phosphoglycerate kinase and triosephosphate isomerase.

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Branny, P; de la Torre, F; Garel, J R

1998-04-01

The structural genes gap, pgk and tpi encoding three glycolytic enzymes, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), 3-phosphoglycerate kinase (PGK) and triosephosphate isomerase (TPI), respectively, have been cloned and sequenced from Lactobacillus delbrueckii subsp. bulgaricus (L. bulgaricus). The genes were isolated after screening genomic sublibraries with specific gap and pgk probes obtained by PCR amplification of chromosomal DNA with degenerate primers corresponding to amino acid sequences highly conserved in GAPDHs and PGKs. Nucleotide sequencing revealed that the three genes were organized in the order gap-pgk-tpi. The translation start codons of the three genes were identified by alignment of the N-terminal sequences. These genes predicted polypeptide chains of 338, 403 and 252 amino acids for GAPDH, PGK and TPI, respectively, and they were separated by 96 bp between gap and pgk, and by only 18 bp between pgk and tpi. The codon usage in gap, pgk, tpi and three other glycolytic genes from L. bulgaricus differed, noticeably from that in other chromosomal genes. The site of transcriptional initiation was located by primer extension, and a probable promoter was identified for the gap-pgk-tpi operon. Northern hybridization of total RNA with specific probes showed two transcripts, an mRNA of 1.4 kb corresponding to the gap gene, and a less abundant mRNA of 3.4 kb corresponding to the gap-pgk-tpi cluster. The absence of a visible terminator in the 3'-end of the shorter transcript and the location of this 3'-end inside the pgk gene indicated that this shorter transcript was produced by degradation of the longer one, rather than by an early termination of transcription after the gap gene.

Cloning and nucleotide sequence analysis of pepV, a carnosinase gene from Lactobacillus delbrueckii subsp. lactis DSM 7290, and partial characterization of the enzyme.

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Vongerichten, K F; Klein, J R; Matern, H; Plapp, R

1994-10-01

Cell extracts of Lactobacillus delbrueckii subsp. lactis DSM 7290 were found to exhibit unique peptolytic ability against unusual beta-alanyl-dipeptides. In order to clone the gene encoding this activity, designated pepV, a gene library of strain DSM 7290 genomic DNA, prepared in the low-copy-number plasmid pLG339, was screened for heterologous expression in Escherichia coli. Recombinant clones harbouring pepV were identified by their ability to allow the utilization of carnosine (beta-alanyl-histidine) as a source of histidine by the E. coli mutant strain UK197 (pepD, hisG). Complementation was observed in a colony harbouring a recombinant plasmid (pKV101), carrying pepV. A 2.4 kb fragment containing pepV was subcloned and its nucleotide sequence revealed an open reading frame (ORF) of 1413 nucleotides, corresponding to a protein with predicted molecular mass of 51998 Da. A single transcription initiation site 71 bp upstream of the ATG translational start codon was identified by primer extension. No significant homology was detected between pepV or its deduced amino acid sequence with any entry in the databases. The only similarity was found in a region conserved in the ArgE/DapE/CPG2/YscS family of proteins. This observation, and protease inhibitor studies, indicated that pepV is of the metalloprotease type. A second ORF present in the sequenced fragment showed extensive homology to a variety of amino acid permeases from E. coli and Saccharomyces cerevisiae.

Molecular Interaction between Lipoteichoic Acids and Lactobacillus delbrueckii Phages Depends on d-Alanyl and α-Glucose Substitution of Poly(Glycerophosphate) Backbones▿

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Räisänen, Liisa; Draing, Christian; Pfitzenmaier, Markus; Schubert, Karin; Jaakonsaari, Tiina; von Aulock, Sonja; Hartung, Thomas; Alatossava, Tapani

2007-01-01

Lipoteichoic acids (LTAs) have been shown to act as bacterial counterparts to the receptor binding proteins of LL-H, LL-H host range mutant LL-H-a21, and JCL1032. Here we have used LTAs purified by hydrophobic interaction chromatography from different phage-resistant and -sensitive strains of Lactobacillus delbrueckii subsp. lactis. Nuclear magnetic resonance analyses revealed variation in the degree of α-glucosyl and d-alanyl substitution of the 1,3-linked poly(glycerophosphate) LTAs between the phage-sensitive and phage-resistant strains. Inactivation of phages was less effective if there was a high level of d-alanine residues in the LTA backbones. Prior incubation of the LTAs with α-glucose-specific lectin inhibited the LL-H phage inactivation. The overall level of decoration or the specific spatial combination of α-glucosyl-substituted, d-alanyl-substituted, and nonsubstituted glycerol residues may also affect phage adsorption. PMID:17416656

Differentiation studies of predominant lactic acid bacteria isolated ...

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Jane

2011-08-08

Aug 8, 2011 ... Lactobacillus plantarum subsp. plantarum NBRC 15891 as a reference strain. But many .... with conserved primers close to the 3_ and 5_ ends of the gene. ... specific. Agarose gel electrophoresis was done to examine the ..... Lactobacillus delbrueckii subsp. delbrueckii LMG 6412T (AM087689). AA2. AA5.

Protein Pattern and Plasmid Profile of Lactic Acid Bacteria Isolated from Dahi, A Traditional Fermented Milk Product of Pakistan

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Tariq Masud

2007-01-01

Full Text Available A total of 116 isolates were identified from randomly collected market dahi samples from Rawalpindi, Pakistan. Lactic acid bacteria dominated the microbial population of dahi and were identified according to their morphological and physiological characteristics. Among these lactobacilli were frequently occurring organisms. The phenotypic and biochemical analyses gave a diversity of species (8 presumptive species. The most abundant species were Lactobacillus delbrueckii subsp. bulgaricus (28 isolates and Streptococcus thermophilus (25 isolates. Some contaminants such as Staphylococcus, Micrococcus and Saccharomyces spp. were also observed. The whole cell protein profiles of selected strains of lactic acid bacteria were examined by SDS-PAGE. It was observed that each species yielded a different electrophoretic pattern. It was further observed that among the strains investigated for the analysis of plasmid DNA 22 strains were found positive, 8 strains of L. delbrueckii subsp. bulgaricus followed by 5 of L. acidophilus, 4 of L. casei, 3 of L. helveticus and one of each L. delbrueckii subsp. delbrueckii and L. delbrueckii subsp. lactis, whereas no plasmid was observed in S. thermophilus and L. lactis strains investigated during the study. All the plasmids isolated were mostly large size plasmids and ranged from 20 to 25 kb in size.

Effect of Lactobacillus sp. isolates supernatant on Escherichia coli O157:H7 enhances the role of organic acids production as a factor for pathogen control

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Larissa B. Poppi

2015-04-01

Full Text Available Many attempts have been made to establish the control of foodborne pathogens through Lactobacillus isolates and their metabolism products with success being obtained in several situations. The aim of this study was to investigate the antagonistic effect of eight Lactobacillus isolates, including L. casei subsp. pseudoplantarum, L. plantarum, L. reuteri and L. delbrueckii subsp. delbrueckii, on the pathogenic Escherichia colistrain O157:H7. The inhibitory effect of pure cultures and two pooled cultures supernatants of Lactobacillus on the growth of pathogenic bacteria was evaluated by the spot agar method and by monitoring turbidity. Antimicrobial activity was confirmed for L. reuteri and L. delbrueckii subsp. delbrueckii and for a pool of lactic acid bacteria. The neutralized supernatant of the pool exerted a higher antimicrobial activity than that of the individual strains. Furthermore, D-lactic acid and acetic acid were produced during growth of the Lactobacillus isolates studied.

Role of mono- and oligosaccharides from FOS as stabilizing agents during freeze-drying and storage of Lactobacillus delbrueckii subsp. bulgaricus.

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Romano, Nelson; Schebor, Carolina; Mobili, Pablo; Gómez-Zavaglia, Andrea

2016-12-01

The aim of this work was to assess the role of mono- and oligosaccharides present in fructo-oligosaccharides (FOS) mixtures as protective agents during freeze-drying and storage of Lactobacillus delbrueckii subsp. bulgaricus CIDCA 333. Different FOS mixtures were enzymatically obtained from sucrose and further purified by removing the monosaccharides produced as secondary products. Their glass transition temperatures (T g ) were determined at 11, 22 and 33% relative humidity (RH). Bacterial cultures were freeze-dried in the presence of 20% w/v solutions of the studied FOS. Their protective effect during freeze-drying was assessed by bacterial plate counting, and by determining the lag time from growth kinetics and the uptake of propidium iodide (PI). Plate counting during bacterial storage at 4°C, and 11, 22 and 33% RH for 80days completed this rational analysis of the protective effect of FOS. Purification of FOS led to an increase of T g in all the conditions assayed. Microorganisms freeze-dried in the presence of non-purified FOS were those with the shortest lag times. Bacteria freeze-dried with pure or commercial FOS (92% of total FOS) showed larger lag times (8.9-12.6h). The cultivability of microorganisms freeze-dried with non-purified FOS and with sucrose was not significantly different from that of bacteria before freeze-drying (8.74±0.14logCFU/mL). Pure or commercial FOS were less efficient in protecting bacteria during freeze-drying. All the protectants prevented membrane damage. The cultivability of bacteria freeze-dried with FOS decayed <1logarithmicunit after 80days of storage at 11% RH. When storing at 22 and 33% RH, pure and commercial FOS were those that best protected bacteria, and FOS containing monosaccharides were less efficient. The effect of FOS on bacterial protection is the result of a balance between monosaccharides, sucrose and larger FOS in the mixtures: the smallest sugars are more efficient in protecting lipid membranes, and the

Unusual Structure of the attB Site of the Site-Specific Recombination System of Lactobacillus delbrueckii Bacteriophage mv4

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Auvray, Frédéric; Coddeville, Michèle; Ordonez, Romy Catoira; Ritzenthaler, Paul

1999-01-01

The temperate phage mv4 integrates its genome into the chromosome of Lactobacillus delbrueckii subsp. bulgaricus by site-specific recombination within the 3′ end of a tRNASer gene. Recombination is catalyzed by the phage-encoded integrase and occurs between the phage attP site and the bacterial attB site. In this study, we show that the mv4 integrase functions in vivo in Escherichia coli and we characterize the bacterial attB site with a site-specific recombination test involving compatible plasmids carrying the recombination sites. The importance of particular nucleotides within the attB sequence was determined by site-directed mutagenesis. The structure of the attB site was found to be simple but rather unusual. A 16-bp DNA fragment was sufficient for function. Unlike most genetic elements that integrate their DNA into tRNA genes, none of the dyad symmetry elements of the tRNASer gene were present within the minimal attB site. No inverted repeats were detected within this site either, in contrast to the lambda site-specific recombination model. PMID:10572145

Characterization of newly isolated Lactobacillus delbrueckii-like strain MF-07 isolated from chicken and its role in isoflavone biotransformation.

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Iqbal, Muhammad Farooq; Zhu, Wei-Yun

2009-02-01

Cecal microbiota of chicken was screened for bacteria involved in the biotransformation of isoflavones. A new facultative anaerobic bacterium, capable of deglycosylation of the isoflavone genistin, was isolated and identified as a Lactobacillus delbrueckii-like strain. The isolate MF-07 was Gram-positive, facultatively anaerobic, catalase negative, non-spore-forming, nonmotile and a straight rod. The polyphasic taxonomic data, along with 16S rRNA gene sequence comparison, demonstrated that the isolate MF-07 was most closely related to L. delbrueckii group of the Lactobacillus genus. Considerable amounts of genistein were accumulated with genistin as a substrate within the first 12 h of fermentation. Formononetin and daidzein were not metabolized. The influence of several carbon sources on the growth of the isolate MF-07 and biotransformation of genistin was also investigated. This is the first study in which an anaerobic Lactobacillus bacterium from the chicken intestinal tract that metabolizes genistin to produce its bioactive metabolite was identified and characterized.

Influence of culture conditions and preconditioning on survival of Lactobacillus delbrueckii subspecies bulgaricus ND02 during lyophilization.

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Shao, Yuyu; Gao, Shuran; Guo, Huiling; Zhang, Heping

2014-03-01

The cryotolerance of Lactobacillus delbrueckii ssp. bulgaricus is weak during vacuum freeze-drying. Many factors affect cryoresistance of these bacteria, such as cryoprotectant composition, the lyophilization technology used, and the intrinsic characteristics of the bacteria. In this research, we explored the fermentation technology and other preconditioning treatments of cells in improving the cryoresistance of Lactobacillus delbrueckii ssp. bulgaricus strains during lyophilization. The addition of yeast extract in the propagation medium exerted a negative effect on the cryotolerance of these bacteria and decreased survival during lyophilization. The count of the freeze-dried cells from medium containing a high level (4%) of yeast extract was only 4.1 × 10(9) cfu/g, indicating a death rate as high as 88%, compared with the culture medium without yeast extract, with a lower death rate of 44.7%. When Lactobacillus delbrueckii ssp. bulgaricus ND02 was propagated in yeast extract-free de Man, Rogosa, and Sharpe broth at a set pH value of 5.1, the cells showed unexpectedly higher survival after freeze-drying. Viable counts of the lyophilized cell of strain ND02 cultivated at pH 5.1 could reach 1.05 × 10(11)cfu/g and survival of the freeze-drying process was 68.3%, whereas at pH 5.7, survival was only 51.2%. We also examined the effects of pretreatment of cells on survival of the bacteria after vacuum freeze-drying. By analyzing the effect of pretreatment conditions on the expression of cold- and heat-shock genes, we established 2 pretreatments that improved survival of cells after lyophilization. Optimal fermentation conditions and pretreatment of the cell-cryoprotectant mixture at 10°C for 2h or 37°C for 30 min improved the cryoresistance of 4 strains of Lactobacillus delbrueckii ssp. bulgaricus to varying degrees. Cells of IMAU20269 and IMAU20291 that were pretreated showed enhanced survival of 16.06 and 16.82%, respectively, after lyophilization. Expression of

Plasmid integration in a wide range of bacteria mediated by the integrase of Lactobacillus delbrueckii bacteriophage mv4.

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Auvray, F; Coddeville, M; Ritzenthaler, P; Dupont, L

1997-01-01

Bacteriophage mv4 is a temperate phage infecting Lactobacillus delbrueckii subsp. bulgaricus. During lysogenization, the phage integrates its genome into the host chromosome at the 3' end of a tRNA(Ser) gene through a site-specific recombination process (L. Dupont et al., J. Bacteriol., 177:586-595, 1995). A nonreplicative vector (pMC1) based on the mv4 integrative elements (attP site and integrase-coding int gene) is able to integrate into the chromosome of a wide range of bacterial hosts, including Lactobacillus plantarum, Lactobacillus casei (two strains), Lactococcus lactis subsp. cremoris, Enterococcus faecalis, and Streptococcus pneumoniae. Integrative recombination of pMC1 into the chromosomes of all of these species is dependent on the int gene product and occurs specifically at the pMC1 attP site. The isolation and sequencing of pMC1 integration sites from these bacteria showed that in lactobacilli, pMC1 integrated into the conserved tRNA(Ser) gene. In the other bacterial species where this tRNA gene is less or not conserved; secondary integration sites either in potential protein-coding regions or in intergenic DNA were used. A consensus sequence was deduced from the analysis of the different integration sites. The comparison of these sequences demonstrated the flexibility of the integrase for the bacterial integration site and suggested the importance of the trinucleotide CCT at the 5' end of the core in the strand exchange reaction. PMID:9068626

Proteomic characterization of the acid tolerance response in Lactobacillus delbrueckii subsp. bulgaricus CAUH1 and functional identification of a novel acid stress-related transcriptional regulator Ldb0677.

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Zhai, Zhengyuan; Douillard, François P; An, Haoran; Wang, Guohong; Guo, Xinghua; Luo, Yunbo; Hao, Yanling

2014-06-01

To overcome the deleterious effects of acid stress, Lactobacillus delbrueckii subsp. bulgaricus (L. bulgaricus) elicits an adaptive response to acid stress. In this study, proteomics approach complemented by transcriptional analysis revealed some cellular changes in L. bulgaricus CAUH1 during acid adaptation. We observed an increase of glycolysis-associated proteins, promoting an optimal utilization of carbohydrates. Also, rerouting of the pyruvate metabolism to fatty acid biosynthesis was observed, indicating a possible modification of the cell membrane rigidity and impermeability. In addition, expression of ribosomal protein S1 (RpsA) was repressed; however, the expression of EF-Tu, EF-G and TypA was up-regulated at both protein and transcript levels. This suggests a reduction of protein synthesis in response to acid stress along with possible enhancement of the translational accuracy and protein folding. It is noteworthy that the putative transcriptional regulator Ldb0677 was 1.84-fold up-regulated. Heterologous expression of Ldb0677 was shown to significantly enhance acid resistance in host strain Lactococcus lactis. To clarify its role in transcriptional regulation network, the DNA-binding specificity of Ldb0677 was determined using bacterial one-hybrid and electrophoretic mobility shift assay. The identification of a binding motif (SSTAGACR) present in the promoter regions of 22 genes indicates that it might function as a major regulator in acid stress response in L. bulgaricus. © 2013 Society for Applied Microbiology and John Wiley & Sons Ltd.

Local and systemic immune mechanisms underlying the anti-colitis effects of the dairy bacterium Lactobacillus delbrueckii.

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Clarissa Santos Rocha

Full Text Available Several probiotic bacteria have been proposed for treatment or prevention of inflammatory bowel diseases (IBD, showing a protective effect in animal models of experimental colitis and for some of them also in human clinical trials. While most of these probiotic bacteria are isolated from the digestive tract, we recently reported that a Lactobacillus strain isolated from cheese, L. delbrueckii subsp. lactis CNRZ327 (Lb CNRZ327, also possesses anti-inflammatory effects in vitro and in vivo, demonstrating that common dairy bacteria may be useful in the treatment or prevention of IBD. Here, we studied the mechanisms underlying the protective effects of Lb CNRZ327 in vivo, in a mouse dextran sodium sulfate (DSS colitis model. During colitis, Lb CNRZ327 modulated the production of TGF-β, IL-6, and IL-12 in colonic tissue and of TGF-β and IL-6 in the spleen, and caused an expansion of CD4+Foxp3+ regulatory T cells in the cecal lymph nodes. Moreover, a strong tendency to CD4+Foxp3+ expansion was also observed in the spleen. The results of this study for the first time show that orally administered dairy lactobacilli can not only modulate mucosal but also systemic immune responses and constitute an effective treatment of IBD.

Local and systemic immune mechanisms underlying the anti-colitis effects of the dairy bacterium Lactobacillus delbrueckii.

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Santos Rocha, Clarissa; Gomes-Santos, Ana Cristina; Garcias Moreira, Thais; de Azevedo, Marcela; Diniz Luerce, Tessalia; Mariadassou, Mahendra; Longaray Delamare, Ana Paula; Langella, Philippe; Maguin, Emmanuelle; Azevedo, Vasco; Caetano de Faria, Ana Maria; Miyoshi, Anderson; van de Guchte, Maarten

2014-01-01

Several probiotic bacteria have been proposed for treatment or prevention of inflammatory bowel diseases (IBD), showing a protective effect in animal models of experimental colitis and for some of them also in human clinical trials. While most of these probiotic bacteria are isolated from the digestive tract, we recently reported that a Lactobacillus strain isolated from cheese, L. delbrueckii subsp. lactis CNRZ327 (Lb CNRZ327), also possesses anti-inflammatory effects in vitro and in vivo, demonstrating that common dairy bacteria may be useful in the treatment or prevention of IBD. Here, we studied the mechanisms underlying the protective effects of Lb CNRZ327 in vivo, in a mouse dextran sodium sulfate (DSS) colitis model. During colitis, Lb CNRZ327 modulated the production of TGF-β, IL-6, and IL-12 in colonic tissue and of TGF-β and IL-6 in the spleen, and caused an expansion of CD4+Foxp3+ regulatory T cells in the cecal lymph nodes. Moreover, a strong tendency to CD4+Foxp3+ expansion was also observed in the spleen. The results of this study for the first time show that orally administered dairy lactobacilli can not only modulate mucosal but also systemic immune responses and constitute an effective treatment of IBD.

In vitro adhesion and anti-inflammatory properties of native Lactobacillus fermentum and Lactobacillus delbrueckii spp.

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Archer, A C; Kurrey, N K; Halami, P M

2018-03-14

This study aimed at characterizing the adhesion and immune-stimulatory properties of native probiotic Lactobacillus fermentum (MCC 2759 and MCC 2760) and Lactobacillus delbrueckii MCC 2775. Adhesion of the strains was assessed in Caco-2 and HT-29 cell lines. Expression of adhesion and immune markers were evaluated in Caco-2 cells by real-time qPCR. The cultures displayed >80% of adhesion to both cell lines and also induced the expression of mucin-binding protein (mub) gene in the presence of mucin, bile and pancreatin. Adhesion was mediated by carbohydrate and proteinaceous factors. The cultures stimulated the expression of inflammatory cytokines in Caco-2 cells. However, pro-inflammatory genes were down-regulated upon challenge with lipopolysaccharide and IL-10 was up-regulated by the cultures. Cell wall extract of L. fermentum MCC 2760 induced the expression of IL-6 by 5·47-fold, whereas crude culture filtrate enhanced the expression of IL-10 by 14·87-fold compared to LPS control. The bacterial cultures exhibited strong adhesion and anti-inflammatory properties. This is the first report to reveal the role of adhesion markers of L. fermentum and L. delbrueckii by qPCR. The strain-specific anti-inflammatory property of native cultures may be useful to alleviate inflammatory conditions and develop a target-based probiotic. © 2018 The Society for Applied Microbiology.

Lactobacillus delbrueckii TUA4408L and its extracellular polysaccharides attenuate enterotoxigenic Escherichia coli-induced inflammatory response in porcine intestinal epitheliocytes via Toll-like receptor-2 and 4.

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Wachi, Satoshi; Kanmani, Paulraj; Tomosada, Yohsuke; Kobayashi, Hisakazu; Yuri, Toshihito; Egusa, Shintaro; Shimazu, Tomoyuki; Suda, Yoshihito; Aso, Hisashi; Sugawara, Makoto; Saito, Tadao; Mishima, Takashi; Villena, Julio; Kitazawa, Haruki

2014-10-01

Immunobiotics are known to modulate intestinal immune responses by regulating Toll-like receptor (TLR) signaling pathways, which are responsible for the induction of cytokines and chemokines in response to microbial-associated molecular patterns. However, little is known about the immunomodulatory activity of compounds or molecules from immunobiotics. We evaluated whether Lactobacillus delbrueckii subsp. delbrueckii TUA4408L (Ld) or its extracellular polysaccharide (EPS): acidic EPS (APS) and neutral EPS (NPS), modulated the response of porcine intestinal epitheliocyte (PIE) cells against Enterotoxigenic Escherichia coli (ETEC) 987P. The roles of TLR2, TLR4, and TLR negative regulators in the immunoregulatory effects were also studied. ETEC-induced inflammatory cytokines were downregulated when PIE cells were prestimulated with both Ld or EPSs. Ld, APS, and NPS inhibited ETEC mediated mitogen-activated protein kinase (MAPK) and nuclear factor-κB (NF-κB) activation by upregulating TLR negative regulators. The capability of Ld to suppress inflammatory cytokines was diminished when PIE cells were blocked with anti-TLR2 antibody, while APS failed to suppress inflammatory cytokines when cells were treated with anti-TLR4 antibody. Induction of Ca²⁺ fluxes in TLR knockdown cells confirmed that TLR2 plays a principal role in the immunomodulatory action of Ld, while the activity of APS is mediated by TLR4. In addition, NPS activity depends on both TLR4 and TLR2. Ld and its EPS have the potential to be used for the development of anti-inflammatory functional foods to prevent intestinal diseases in both humans and animals. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Ameliorated effects of Lactobacillus delbrueckii subsp. lactis DSM 20076 and Pediococcus acidilactici NNRL B-5627 on Fumonisin B1-induced Hepatotoxicity and Nephrotoxicity in rats

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Amira A. Abdellatef

2016-04-01

Full Text Available Oxidative stress has been implicated in a number of human regeneration and disease processes including atherosclerosis, pulmonary fibrosis, cancer, and different neurodegenerative diseases. The aim of this study was to evaluate the protective effects of Lactobacillus delbrueckii subsp. lactis DSM 20076 (LL-DSM and Pediococcus acidilactici NNRL B-5627 (PA-NNRL against the hepatic- and nephro-toxicity of fumonisin B1 (FB1 in FB1-treated rats for an experimental period of 4-weeks. Eighty mature male Sprague-Dawley rats were divided to 12 groups: 1 untreated group; 3 groups fed by a FB1-contaminated diet (50, 100 and 200 mg FB1/kg diet, respectively; 1 group fed orally by LL-DSM (1 ml/d; 1 group fed orally by PA-NNRL (1 ml/d; 3 groups co-administered by FB1-contaminated diet and LL-DSM (1 ml/d, and 3 groups co-administered by FB1-contaminated diet and PA-NNRL (1 ml/d. Malonaldehyde (MDA nitric oxide, glutathione content, SOD activity, total antioxidant capacity (TAC, total oxidant status (TOS and oxidative stress index (OSI were determined. DPA assay was used to assess apoptosis in liver and kidney tissues. The animals fed with FB1-contaminated diet showed a significant increase in oxidative stress markers and DNA fragmentation accompanied with significant decrease in GSH content, SOD activity, and TAC in liver and kidney tissues, especially at high-dosage of FB1 (T200. Probiotics antioxidant strains (LL-DSM and PA-NNRL relatively succeeded to restore almost all parameters investigated as well as to reduce DNA fragmentation in liver and kidney tissues. As a conclusion, probiotics may induce its protective role via increasing the antioxidant capacity, inhibition of lipid peroxidation, scavenging of free radicals and decreasing DNA lesions in liver and kidney of experimental animals tested.

Determination of the Presence of crpgenes in Staphylococcus aureus, Staphylococcus epidermidis, Lactobacillus delbrueckii and Corynebacterium veraSuş

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BELDÜZ, Ali Osman; DEMİRBAĞ, Zihni; DÜLGER, Sabriye

2014-01-01

Polymerase chain reaction (PCR) was employed to detect the presence of cyclic AMP receptor protein (CPR) in a number of diverse organisms. In PCR, two primers specific to the crp gene of Escherichia coli were used. Staphylococcus aureus, Staphylococcus epidermidis, Lactobacillus delbrueckii and Corynebacterium veraSuş all showed the same size of PCR frağments (708 bp) and same restriction frağment length polymorphizm (RFLP).

Temperate and virulent Lactobacillus delbrueckii bacteriophages: comparison of their thermal and chemical resistance.

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Ebrecht, Ana C; Guglielmotti, Daniela M; Tremmel, Gustavo; Reinheimer, Jorge A; Suárez, Viviana B

2010-06-01

The aim of this work was to study the efficiency of diverse chemical and thermal treatments usually used in dairy industries to control the number of virulent and temperate Lactobacillus delbrueckii bacteriophages. Two temperate (Cb1/204 and Cb1/342) and three virulent (BYM, YAB and Ib3) phages were studied. The thermal treatments applied were: 63 degrees C for 30 min (low temperature--long time, LTLT), 72 degrees C for 15 s (high temperature--short time, HTST), 82 degrees C for 5 min (milk destined to yogurt elaboration) and 90 degrees C for 15 min (FIL-IDF). The chemical agents studied were: sodium hypochlorite, ethanol, isopropanol, peracetic acid, biocides A (quaternary ammonium chloride), B (hydrogen peroxide, peracetic acid and peroctanoic acid), C (alkaline chloride foam), D (p-toluensulfonchloroamide, sodium salt) and E (ethoxylated nonylphenol and phosphoric acid). The kinetics of inactivation were drew and T(99) (time necessary to eliminate the 99% of phage particles) calculated. Results obtained showed that temperate phages revealed lower resistance than the virulent ones to the treatment temperatures. Biocides A, C, E and peracetic acid showed a notable efficiency to inactivate high concentrations of temperate and virulent L. delbrueckii phages. Biocide B evidenced, in general, a good capacity to eliminate the phage particles. Particularly for this biocide virulent phage Ib3 showed the highest resistance in comparison to the rest of temperate and virulent ones. On the contrary, biocide D and isopropanol presented a very low capacity to inactivate all phages studied. The efficiency of ethanol and hypochlorite was variable depending to the phages considered. These results allow a better knowledge and give useful information to outline more effective treatments to reduce the phage infections in dairy plants. 2009 Elsevier Ltd. All rights reserved.

Estudio de nuevas levaduras Killer "Saccharomyces cerevisiae" y "Torulaspora delbrueckii" para elaborar vinos tranquilos y espumosos

OpenAIRE

Velázquez Molinero, Rocío

2016-01-01

Se analizan dos nuevos tipos de levaduras vínicas killer de amplio espectro antifúngico: Sacharomyces cerevisiae Klus y Torulaspora delbrueckii Kbarr. Ambas matan a todos los tipos de levaduras S. cerevisiae conocidos, killer y sensibles, además de muchas otras especies de levaduras no-Saccharomyces. El receptor de la pared celular de las levaduras sensibles a ambas toxinas parece ser el beta-glucano. El fenotipo killer de estas levaduras está codificado en virus de dsRNA de tamaño mediano, M...

Partial characterization of ribosomal operons of Lactobacillus delbrueckii UFV H2b20 Caracterização parcial de operons ribossomais de Lactobacillus delbrueckii UFV H2b20

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Juliana Teixeira de Magalhães

2005-06-01

Full Text Available Ribosomal operons are great tools for microbe community characterization and for microorganisms relationship study, particularly in the case of the acid lactic bacteria. The ribosomal operon of the probiotic strain Lactobacillus delbrueckii UFV H2b20 was partially characterized. A genomic library of this strain was constructed and the clones with partial ribosomal operon were sub-cloned using the shot-gun method for subsequent sequencing with the forward primer. The sequence analysis revealed that the 3' end of the rDNA 16S was following by the short spacer region 1 (16S-23S and that the 3' end of the rDNA 23S was following by the short spacer region 2 (23S-5S, which preceded the rDNA 5S. In the flanking region of the rDNA 5S gene of this operon rrn, a region encoding six tRNAs was detected.Operons ribossomais têm sido instrumentos importantes na caracterização de comunidades microbianas e no estudo de relacionamentos entre microrganismos, principalmente em bactérias do ácido láctico. Operons ribossomais da linhagem probiótica, Lactobacillus delbrueckii UFV H2b20, foram parcialmente caracterizados. Um banco genômico da linhagem foi construído e os clones, contendo parte do operon ribossomal, foram subclonados pelo método de "shot gun", para em seguida serem seqüenciados com primer "forward". As seqüências indicaram a presença da extremidade 3' do rDNA 16S seguida da região espaçadora curta 1 (16S-23S e a presença da extremidade 3' do rDNA 23S seguido da região espaçadora 2 (23S-5S, que por sua vez precedia o rDNA 5S. Adjacente ao gene rDNA 5S deste operon rrn uma região codificadora de 6 tRNAs foi detectada.

Metabolomic and proteomic analysis of D-lactate-producing Lactobacillus delbrueckii under various fermentation conditions.

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Liang, Shaoxiong; Gao, Dacheng; Liu, Huanhuan; Wang, Cheng; Wen, Jianping

2018-05-28

As an important feedstock monomer for the production of biodegradable stereo-complex poly-lactic acid polymer, D-lactate has attracted much attention. To improve D-lactate production by microorganisms such as Lactobacillus delbrueckii, various fermentation conditions were performed, such as the employment of anaerobic fermentation, the utilization of more suitable neutralizing agents, and exploitation of alternative nitrogen sources. The highest D-lactate titer could reach 133 g/L under the optimally combined fermentation condition, increased by 70.5% compared with the control. To decipher the potential mechanisms of D-lactate overproduction, the time-series response of intracellular metabolism to different fermentation conditions was investigated by GC-MS and LC-MS/MS-based metabolomic analysis. Then the metabolomic datasets were subjected to weighted correlation network analysis (WGCNA), and nine distinct metabolic modules and eight hub metabolites were identified to be specifically associated with D-lactate production. Moreover, a quantitative iTRAQ-LC-MS/MS proteomic approach was employed to further analyze the change of intracellular metabolism under the combined fermentation condition, identifying 97 up-regulated and 42 down-regulated proteins compared with the control. The in-depth analysis elucidated how the key factors exerted influence on D-lactate biosynthesis. The results revealed that glycolysis and pentose phosphate pathways, transport of glucose, amino acids and peptides, amino acid metabolism, peptide hydrolysis, synthesis of nucleotides and proteins, and cell division were all strengthened, while ATP consumption for exporting proton, cell damage, metabolic burden caused by stress response, and bypass of pyruvate were decreased under the combined condition. These might be the main reasons for significantly improved D-lactate production. These findings provide the first omics view of cell growth and D-lactate overproduction in L. delbrueckii, which

Draft Genome Sequence of Lactobacillus delbrueckii Strain #22 Isolated from a Patient with Short Bowel Syndrome and Previous d-Lactic Acidosis and Encephalopathy.

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Domann, Eugen; Fischer, Florence; Glowatzki, Fabian; Fritzenwanker, Moritz; Hain, Torsten; Zechel-Gran, Silke; Giffhorn-Katz, Susanne; Neubauer, Bernd A

2016-07-28

d-Lactic acidosis with associated encephalopathy caused by overgrowth of intestinal lactic acid bacteria is a rarely diagnosed neurological complication of patients with short bowel syndrome. Here, we report the draft genome sequence of Lactobacillus delbrueckii strain #22 isolated from a patient with short bowel syndrome and previous d-lactic acidosis/encephalopathy. Copyright © 2016 Domann et al.

Identification of Lactobacillus delbrueckii and Streptococcus thermophilus Strains Present in Artisanal Raw Cow Milk Cheese Using Real-time PCR and Classic Plate Count Methods.

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Stachelska, Milena A

2017-12-04

The aim of this paper was to detect Lactobacillus delbrueckii and Streptococcus thermophilus using real-time quantitative PCR assay in 7-day ripening cheese produced from unpasteurised milk. Real-time quantitative PCR assays were designed to identify and enumerate the chosen species of lactic acid bacteria (LAB) in ripened cheese. The results of molecular quantification and classic bacterial enumeration showed a high level of similarity proving that DNA extraction was carried out in a proper way and that genomic DNA solutions were free of PCR inhibitors. These methods revealed the presence of L. delbrueckii and S. thermophilus. The real-time PCR enabled quantification with a detection of 101-103 CFU/g of product. qPCR-standard curves were linear over seven log units down to 101 copies per reaction; efficiencies ranged from 77.9% to 93.6%. Cheese samples were analysed with plate count method and qPCR in parallel. Compared with the classic plate count method, the newly developed qPCR method provided faster and species specific identification of two dairy LAB and yielded comparable quantitative results.

Enhanced natural killer cell activation by exopolysaccharides derived from yogurt fermented with Lactobacillus delbrueckii ssp. bulgaricus OLL1073R-1.

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Makino, Seiya; Sato, Asako; Goto, Ayako; Nakamura, Marie; Ogawa, Miho; Chiba, Yoshika; Hemmi, Jun; Kano, Hiroshi; Takeda, Kazuyoshi; Okumura, Ko; Asami, Yukio

2016-02-01

Yogurt is generally recognized as a beneficial food for our health, but research into its physiological effects has focused mainly on intestinal dysfunctions such as constipation and diarrhea. We previously found yogurt fermented with Lactobacillus delbrueckii ssp. bulgaricus OLL1073R-1 (hereafter OLL1073R-1) could reduce risks of catching the common cold and flu in human trials. It was assumed that immunostimulatory exopolysaccharide (EPS) produced from OLL1073R-1 play an important role in this context. However, few studies have examined the immunostimulatory effects of traditional Bulgarian yogurts fermented with different strains of lactobacilli and their metabolites. Therefore, we screened 139 L. delbrueckii ssp. bulgaricus strains and identified OLL1073R-1 as the most robust producer of EPS. This strain was also the only strain that induced the production of IFN-γ in vitro. Oral administration of the EPS or yogurt fermented with OLL1073R-1 and Streptococcus thermophilus OLS3059 (OLL1073R-1 yogurt) augmented natural killer (NK) cell activity and induced IFN-γ production in spleen cells in mice, whereas 2 other yogurts fermented with other strains had no effect on NK cell activity. Cellular preparations of the OLL1073R-1 strain also slightly augmented NK cell activity, but were less effective than EPS itself. The EPS-dependent stimulation of NK cell activity was abrogated in IFN-γ knockout mice and in myeloid differentiation factor 88 knockout mice. Furthermore, IFN-γ production from spleen cells stimulated with EPS was completely blocked with both anti-IL-12 and anti-IL-18 antibodies in vitro. These findings suggest that NK cell activation by OLL1073R-1 yogurt is EPS-dependent, occurs via IL-12- and IL-18-mediated IFN-γ production, and requires myeloid differentiation factor 88. We showed that traditional Bulgarian yogurt could exert immunostimulatory effects by selecting starter strains and part of the mechanisms depend on IFN-γ inducible EPS produced

Growth and exopolysaccharide yield of Lactobacillus delbrueckii ssp. bulgaricus DSM 20081 in batch and continuous bioreactor experiments at constant pH.

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Mende, Susann; Krzyzanowski, Leona; Weber, Jost; Jaros, Doris; Rohm, Harald

2012-02-01

Some Lactobacillus delbrueckii ssp. bulgaricus strains are able to synthesize exopolysaccharides (EPS) and are therefore highly important for the dairy industry as starter cultures. The aim of this study was to investigate the nutritional requirements for growth and EPS production of Lactobacillus delbrueckii ssp. bulgaricus DSM 20081. A medium was developed from a semi-defined medium (SDM) in which glucose was replaced by lactose and different combinations of supplements (nucleobases, vitamins, salts, sodium formate and orotic acid) were added. Constant pH batch fermentation with the modified medium resulted in an EPS yield of approximately 210 mg glucose equivalents per liter medium. This was a 10-fold increase over flask cultivation of this strain in SDM. Although not affecting cell growth, the mixture of salts enhanced the EPS synthesis. Whereas EPS production was approximately 12 mg/g dry biomass without salt supplementation, a significantly higher yield (approximately 20 mg/g dry biomass) was observed after adding the salt mixture. In continuous fermentation, a maximal EPS concentration was obtained at a dilution rate of 0.31/h (80 mg EPS/L), which corresponded to a specific EPS production of 49 mg/g dry biomass. Copyright © 2011 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

SOLID AND LIQUID PINEAPPLE WASTE UTILIZATION FOR LACTIC ACID FERMENTATION USING Lactobacillus delbrueckii

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Abdullah Abdullah

2012-01-01

Full Text Available The liquid and solid  pineapple wastes contain mainly sucrose, glucose, fructose and other nutrients. It therefore can potentially be used as carbon source for fermentation to produce organic acid. Recently, lactic acid has been considered to be an important raw material for production of biodegradable lactate polymer. The experiments were  carried out in batch fermentation using  the  liquid and solid pineapple wastes to produce lactic acid. The anaerobic fermentation of lactic acid were performed at 40 oC, pH 6, 5% inocolum and  50 rpm. Initially  results show that the liquid pineapple waste by  using Lactobacillus delbrueckii can be used as carbon source  for lactic acid fermentation. The production of lactic acid  are found to be 79 % yield, while only  56% yield was produced by using solid waste. 

Discrimination of the Lactobacillus acidophilus group using sequencing, species-specific PCR and SNaPshot mini-sequencing technology based on the recA gene.

Science.gov (United States)

Huang, Chien-Hsun; Chang, Mu-Tzu; Huang, Mu-Chiou; Wang, Li-Tin; Huang, Lina; Lee, Fwu-Ling

2012-10-01

To clearly identify specific species and subspecies of the Lactobacillus acidophilus group using phenotypic and genotypic (16S rDNA sequence analysis) techniques alone is difficult. The aim of this study was to use the recA gene for species discrimination in the L. acidophilus group, as well as to develop a species-specific primer and single nucleotide polymorphism primer based on the recA gene sequence for species and subspecies identification. The average sequence similarity for the recA gene among type strains was 80.0%, and most members of the L. acidophilus group could be clearly distinguished. The species-specific primer was designed according to the recA gene sequencing, which was employed for polymerase chain reaction with the template DNA of Lactobacillus strains. A single 231-bp species-specific band was found only in L. delbrueckii. A SNaPshot mini-sequencing assay using recA as a target gene was also developed. The specificity of the mini-sequencing assay was evaluated using 31 strains of L. delbrueckii species and was able to unambiguously discriminate strains belonging to the subspecies L. delbrueckii subsp. bulgaricus. The phylogenetic relationships of most strains in the L. acidophilus group can be resolved using recA gene sequencing, and a novel method to identify the species and subspecies of the L. delbrueckii and L. delbrueckii subsp. bulgaricus was developed by species-specific polymerase chain reaction combined with SNaPshot mini-sequencing. Copyright © 2012 Society of Chemical Industry.

Molecular comparison of the structural proteins encoding gene clusters of two related Lactobacillus delbrueckii bacteriophages.

Science.gov (United States)

Vasala, A; Dupont, L; Baumann, M; Ritzenthaler, P; Alatossava, T

1993-01-01

Virulent phage LL-H and temperate phage mv4 are two related bacteriophages of Lactobacillus delbrueckii. The gene clusters encoding structural proteins of these two phages have been sequenced and further analyzed. Six open reading frames (ORF-1 to ORF-6) were detected. Protein sequencing and Western immunoblotting experiments confirmed that ORF-3 (g34) encoded the main capsid protein Gp34. The presence of a putative late promoter in front of the phage LL-H g34 gene was suggested by primer extension experiments. Comparative sequence analysis between phage LL-H and phage mv4 revealed striking similarities in the structure and organization of this gene cluster, suggesting that the genes encoding phage structural proteins belong to a highly conservative module. Images PMID:8497043

Purification and characteristics of a novel bacteriocin produced by Enterococcus faecalis L11 isolated from Chinese traditional fermented cucumber.

Science.gov (United States)

Gao, Yurong; Li, Benling; Li, Dapeng; Zhang, Liyuan

2016-05-01

To purify and characterize a novel bacteriocin with broad inhibitory spectrum produced by an isolate of Enterococcus faecalis from Chinese fermented cucumber. E. faecalis L11 produced a bacteriocin with antimicrobial activity against both Escherichia coli and Staphylococcus aureus. The amino acid sequence of the purified bacteriocin, enterocin L11, was assayed by Edman degradation method. It differs from other class II bacteriocins and exhibited a broad antimicrobial activity against not only Gram-positive bacteria, including Bacillus subtilis, S. aureus, Listeria monocytogenes, Sarcina flava, Lactobacillus acidophilus, L. plantarum, L. delbrueckii subsp. delbrueckii, L. delbrueckii subsp. bulgaricus and Streptococcus thermophilus, but also some Gram-negative bacteria including Salmonella typhimurium, E. coli and Shigella flexneri. Enterocin L11 retained 91 % of its activity after holding at 121 °C for 30 min. It was also resistant to acids and alkalis. Enterocin L11 is a novel broad-spectrum Class II bacteriocin produced by E. faecalis L11, and may have potential as a food biopreservative.

The innovative potential of Lactobacillus rhamnosus LR06, Lactobacillus pentosus LPS01, Lactobacillus plantarum LP01, and Lactobacillus delbrueckii Subsp. delbrueckii LDD01 to restore the "gastric barrier effect" in patients chronically treated with PPI: a pilot study.

Science.gov (United States)

Del Piano, Mario; Anderloni, Andrea; Balzarini, Marco; Ballarè, Marco; Carmagnola, Stefania; Montino, Franco; Orsello, Marco; Pagliarulo, Michela; Tari, Roberto; Soattini, Liliana; Sforza, Filomena; Mogna, Luca; Mogna, Giovanni

2012-10-01

LPS01 (DSM 21980), Lactobacillus plantarum LP01 (LMG P-21021), and Lactobacillus delbrueckii subsp. delbrueckii LDD01 (DSM 22106) were administered for 10 days to 10 subjects treated with PPIs for >12 months (group B). In the 60 mg formulation, N-acetylcysteine was included as well in light of its well-known mechanical effects on bacterial biofilms. Gastroscopies were performed at the beginning of the study (d0) in all the groups (A, B, C, and D) and after 10 days (d10) in group B only; that is, at the end of probiotics intake. The total viable cells and total Lactobacillus were quantified in gastric juice and duodenal brushing material from all subjects. The results were compared among all the groups and with the control subjects (group D) to confirm the bacterial overgrowth. A comparison was made also between d0 and d10 in group B to quantify the efficacy of the 4 probiotics administered for 10 days. Fecal samples were collected from all groups at d0, including subjects not treated with PPIs, and in group B only at d10. Specific bacterial classes, namely enterococci, total coliforms, E. coli, molds, and yeasts were quantified in all fecal specimens. The results collected confirmed the strong bacterial overgrowth in the stomach and duodenum of people treated with PPIs compared with subjects with a normal intragastric acidity. It is also worth noting that the bacterial cell counts in subjects who underwent a long-term treatment with a PPI were greater than the results from subjects taking these drugs for 3 to 12 months. The intake of 4 specific probiotic strains with a marked antagonistic activity towards 5 E. coli bacteria, including the enterohaemorrhagic O157:H7 strain, and an effective amount of N-acetylcysteine (NAC) was able to significantly reduce bacterial overgrowth in long-term PPI-treated subjects. Total lactobacilli represented the major percentage of bacterial counts, thus demonstrating the ability of such bacteria to colonize the stomach and the duodenum

CARACTERÍSTICAS FÍSICAS E QUÍMICAS DE BEBIDAS LÁCTEAS FERMENTADAS E PREPARADAS COM SORO DE QUEIJO MINAS FRESCAL PHYSICAL AND CHEMICAL CHARACTERISTICS OF FERMENTED DAIRY BEVERAGES USING MINAS CHEESE WHEY

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Keila Emílio de ALMEIDA

2001-08-01

Full Text Available Nesta pesquisa procurou-se verificar as características físicas e químicas de bebidas lácteas preparadas com três concentrações de soro de queijo Minas Frescal (30, 40 e 50%, empregando-se dois tipos de culturas lácticas: uma tradicional para iogurte (YC-180 contendo cepas mistas de Streptococcus salivarus subsp. thermophilus, Lactobacillus delbrueckii subsp. lactis e Lactobacillus delbrueckii subsp. bulgaricus e outra (ABY-1 contendo cepas mistas de Lactobacillus delbrueckii subsp. bulgaricus, Lactobacillus acidophillus, Bifidobacteria e Streptococcus salivarius subsp. thermophilus. Constatou-se que as bebidas lácteas apresentaram diferença estatística no tempo zero para os teores de gordura e de extrato seco. À medida em que se elevou a proporção de soro em relação ao leite, os teores de gordura e de extrato seco diminuíram. O teor de proteína também diminuiu à medida em que se aumentou o teor de soro nas bebidas lácteas, embora a diferença não tenha sido tão acentuada quanto as observadas para os teores de gordura e de extrato seco. Em relação à lactose, não se constatou diferença entre os tratamentos. Os teores de soro não influenciaram o índice de proteólise das bebidas lácteas. Verificou-se todavia que as bebidas elaboradas com a cultura probiótica ABY-1 apresentaram valores superiores para proteólise quando comparadas às bebidas elaboradas com as culturas YC-180. As bebidas lácteas elaboradas com 30% de soro apresentaram maiores valores para viscosidade. As bebidas elaboradas com a cultura YC-180 apresentaram valores superiores para viscosidade durante o período de armazenamento.This research studies the physical and chemical characteristics of dairy beverages formulated with three different concentrations (30, 40 and 50 % of Minas cheese whey, using two kinds of dairy cultures: the traditional yogurt (YC--180 culture, holding mixed strains of Streptococcus salivarus subsp. thermophilus, Lactobacillus

Structural characterization of a D-isomer specific 2-hydroxyacid dehydrogenase from Lactobacillus delbrueckii ssp. bulgaricus.

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Holton, Simon J; Anandhakrishnan, Madhankumar; Geerlof, Arie; Wilmanns, Matthias

2013-02-01

Hydroxyacid dehydrogenases, responsible for the stereospecific conversion of 2-keto acids to 2-hydroxyacids in lactic acid producing bacteria, have a range of biotechnology applications including antibiotic synthesis, flavor development in dairy products and the production of valuable synthons. The genome of Lactobacillus delbrueckii ssp. bulgaricus, a member of the heterogeneous group of lactic acid bacteria, encodes multiple hydroxyacid dehydrogenases whose structural and functional properties remain poorly characterized. Here, we report the apo and coenzyme NAD⁺ complexed crystal structures of the L. bulgaricusD-isomer specific 2-hydroxyacid dehydrogenase, D2-HDH. Comparison with closely related members of the NAD-dependent dehydrogenase family reveals that whilst the D2-HDH core fold is structurally conserved, the substrate-binding site has a number of non-canonical features that may influence substrate selection and thus dictate the physiological function of the enzyme. Copyright © 2012 Elsevier Inc. All rights reserved.

Fermentation capability of bulk milk under usual conditions

OpenAIRE

BOUŠKOVÁ, Lucie

2012-01-01

The evaluation of changes during fermentation of heat-modified milk in connection with different fermentation temperatures was main goal of this thesis. Titrable acidity, active acidity and growth dynamics of bacteria strains - Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus salivarius subsp. thermophilus were observed during fermentation process.

Diversity and dynamics of lactobacilli populations during ripening of RDO Camembert cheese.

Science.gov (United States)

Henri-Dubernet, Ségolène; Desmasures, Nathalie; Guéguen, Micheline

2008-03-01

The diversity and dynamics of Lactobacillus populations in traditional raw milk Camembert cheese were monitored throughout the manufacturing process in 3 dairies. Culture-dependent analysis was carried out on isolates grown on acidified de Man - Rogosa - Sharpe agar and Lactobacillus anaerobic de Man Rogosa Sharpe agar supplemented with vancomycin and bromocresol green media. The isolates were identified by polymerase chain reaction - temperature gradient gel electrophoresis (PCR-TGGE) and (or) species-specific PCR and (or) sequencing, and Lactobacillus paracasei and Lactobacillus plantarum isolates were characterized by pulsed field gel electrophoresis (PFGE). Milk and cheese were subjected to culture-independent analysis by PCR-TGGE. Presumed lactobacilli were detected by plate counts throughout the ripening process. However, molecular analysis of total DNA and DNA of isolates failed to detect Lactobacillus spp. in certain cases. The dominant species in the 3 dairies was L. paracasei. PFGE analysis revealed 21 different profiles among 39 L. paracasei isolates. Lactobacillus plantarum was the second most isolated species, but it occurred nearly exclusively in one dairy. The other species isolated were Lactobacillus parabuchneri, Lactobacillus fermentum, Lactobacillus acidophilus, Lactobacillus helveticus, a Lactobacillus psittaci/delbrueckii subsp. bulgaricus/gallinarum/crispatus group, Lactobacillus rhamnosus, Lactobacillus delbrueckii subsp. bulgaricus, L. delbrueckii subsp. lactis, Lactobacillus brevis, Lactobacillus kefiri, and Lactobacillus perolens. Lactobacilli diversity at the strain level was high. Dynamics varied among dairies, and each cheese exhibited a specific picture of species and strains.

Development of a Novel Probiotic Yogurt “PENTOYO” with a Fully ...

African Journals Online (AJOL)

HP

Methods: Mother cultures of Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus and L. ... indicating the presence of a sufficient number of viable bacterial cells at 4 oC. .... and galactose uptake and utilization, including ...

Kinetics of Batch Fermentation in the Cultivation of a Probiotic Strain Lactobacillus Delbrueckii Ssp. Bulgaricus B1

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Goranov Bogdan

2015-07-01

Full Text Available A comparative study of kinetic models to describe the dynamics of the fermentation process of culturing of a probiotic strain Lactobacillus delbrueckii ssp. bulgaricus B1 was performed. The models of Monod, Aiba, Tiessier, Hinshelwood and the equation of the logistic curve combined with the model of Ludeking-Piret were used. It has been found that the different models described the observed fermentation dynamics differently. The conducted comparative study demonstrated that the models of Monod and the equation of the logistic curve combined with the model of Ludeking-Piret were suitable for the description of the fermentation dynamics. The mathematical models showed no significant product and/or substrate inhibition. The culture developed with a low specific growth rate, but nevertheless it accumulated 1012-1013 viable cells. The substrate was absorbed primarily from cells in the stationary growth phase rather than cells in the exponential growth phase

Improved Helicobacter pylori Eradication Rate of Tailored Triple Therapy by Adding Lactobacillus delbrueckii and Streptococcus thermophilus in Northeast Region of Thailand: A Prospective Randomized Controlled Clinical Trial

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Taweesak Tongtawee

2015-01-01

Full Text Available Background and Aim. To evaluate the effect of Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus to Helicobacter pylori eradication in different periods of therapeutic protocol. Methods. Infected patients were randomized to one-week tailored triple therapy (esomeprazole 20 mg bid, clarithromycin 500 mg bid/metronidazole 400 mg tid if clarithromycin resistant, and amoxicillin 1000 mg bid with placebo (group 1, n=100; one week of pretreatment with probiotics (group 2, n=100; and one week of pretreatment with probiotic followed by one week of the same probiotics after treatment (group 3, n=100. Result. PP analysis involved 292 patients, 98 in group 1, 97 in group 2, and 97 in group 3. Successful eradication was observed in 229 patients; by PP analysis, the eradication rates were significantly higher (P<0.01, 95% CI; 0.71–0.97 in group 2 and group 3 than group 1. ITT analysis eradication rates were significantly higher in group 2 and group 3 than group 1 (P<0.01 95% CI; 0.72–0.87, and there is no significant difference between the three groups (P=0.32 in terms of adverse events. Conclusion. Adding probiotics before or before and after tailored treatment can improve Helicobacter pylori eradication rates. This trial is registered with Thai Clinical Trials Registry number: TCTR20141209001.

Improved Helicobacter pylori Eradication Rate of Tailored Triple Therapy by Adding Lactobacillus delbrueckii and Streptococcus thermophilus in Northeast Region of Thailand: A Prospective Randomized Controlled Clinical Trial.

Science.gov (United States)

Tongtawee, Taweesak; Dechsukhum, Chavaboon; Leeanansaksiri, Wilairat; Kaewpitoon, Soraya; Kaewpitoon, Natthawut; Loyd, Ryan A; Matrakool, Likit; Panpimanmas, Sukij

2015-01-01

Background and Aim. To evaluate the effect of Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus to Helicobacter pylori eradication in different periods of therapeutic protocol. Methods. Infected patients were randomized to one-week tailored triple therapy (esomeprazole 20 mg bid, clarithromycin 500 mg bid/metronidazole 400 mg tid if clarithromycin resistant, and amoxicillin 1000 mg bid) with placebo (group 1, n=100); one week of pretreatment with probiotics (group 2, n=100); and one week of pretreatment with probiotic followed by one week of the same probiotics after treatment (group 3, n=100). Result. PP analysis involved 292 patients, 98 in group 1, 97 in group 2, and 97 in group 3. Successful eradication was observed in 229 patients; by PP analysis, the eradication rates were significantly higher (P<0.01, 95% CI; 0.71-0.97) in group 2 and group 3 than group 1. ITT analysis eradication rates were significantly higher in group 2 and group 3 than group 1 (P<0.01 95% CI; 0.72-0.87), and there is no significant difference between the three groups (P=0.32) in terms of adverse events. Conclusion. Adding probiotics before or before and after tailored treatment can improve Helicobacter pylori eradication rates. This trial is registered with Thai Clinical Trials Registry number: TCTR20141209001.

Mixed-culture transcriptome analysis reveals the molecular basis of mixed-culture growth in Streptococcus thermophilus and Lactobacillus bulgaricus

NARCIS (Netherlands)

Sieuwerts, S.; Molenaar, D.; Hijum, van S.A.F.T.; Beerthuyzen, M.; Stevens, M.J.A.; Janssen, P.W.; Ingham, C.J.; Bok, de F.A.M.; Vos, de W.M.; Hylckama Vlieg, van J.E.T.

2010-01-01

Many food fermentations are performed using mixed cultures of lactic acid bacteria. Interactions between strains are of key importance for the performance of these fermentations. Yogurt fermentation by Streptococcus thermophilus and Lactobacillus bulgaricus (basonym, Lactobacillus delbrueckii subsp.

Development and use of tuf gene-based primers for the multiplex PCR detection of Lactobacillus acidophilus, Lactobacillus casei group, Lactobacillus delbrueckii, and Bifidobacterium longum in commercial dairy products.

Science.gov (United States)

Sheu, Sen-Je; Hwang, Wen-zhe; Chen, Hsin-Chih; Chiang, Yu-Cheng; Tsen, Hau-Yang

2009-01-01

PCR primers specific for the detection of Lactobacillus acidophilus, Lactobacillus casei group, Lactobacillus delbrueckii, and Bifidobacterium longum were designed based on the elongation factor Tu gene (tuf). The specificity of these four primer sets were confirmed by PCR with 88 bacterial strains of Lactobacillus, Enterococcus, Bifidobacterium, and other bacterial species. Results indicated that these primer sets generated predicted PCR products of 397, 230, 202, and 161 bp for L. acidophilus, L. delbrueckii, L. casei group, and B. longum, respectively. Bacterial species other than the target organisms tested did not generate false-positive results. When these four primer sets were combined for the simultaneous detection of the lactic acid bacteria (LAB) in fermented milk products including yogurt, the LAB species listed on the labels of these products could be identified without the preenrichment step. The identification limit for each LAB strain with this multiplex PCR method was N X 10(3) CFU/ml in milk samples. The results of our multiplex PCR method were confirmed by PCR assay using primers based on the 16S rDNA or the 16S-23S intergenic spacer region and by biochemical tests using the API 50 CHL kit. When this multiplex PCR method was used with the determination of counts of total viable LAB and bifidobacteria, the quality of commercial fermented milk products could be assured.

A low membrane lipid phase transition temperature is associated with a high cryotolerance of Lactobacillus delbrueckii subspecies bulgaricus CFL1.

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Gautier, J; Passot, S; Pénicaud, C; Guillemin, H; Cenard, S; Lieben, P; Fonseca, F

2013-09-01

The mechanisms of cellular damage that lactic acid bacteria incur during freeze-thaw processes have not been elucidated to date. Fourier transform infrared spectroscopy was used to investigate in situ the lipid phase transition behavior of the membrane of Lactobacillus delbrueckii ssp. bulgaricus CFL1 cells during the freeze-thaw process. Our objective was to relate the lipid membrane behavior to membrane integrity losses during freezing and to cell-freezing resistance. Cells were produced by using 2 different culture media: de Man, Rogosa, and Sharpe (MRS) broth (complex medium) or mild whey-based medium (minimal medium commonly used in the dairy industry), to obtain different membrane lipid compositions corresponding to different recovery rates of cell viability and functionality after freezing. The lipid membrane behavior studied by Fourier transform infrared spectroscopy was found to be different according to the cell lipid composition and cryotolerance. Freeze-resistant cells, exhibiting a higher content of unsaturated and cyclic fatty acids, presented a lower lipid phase transition temperature (Ts) during freezing (Ts=-8°C), occurring within the same temperature range as the ice nucleation, than freeze-sensitive cells (Ts=+22°C). A subzero value of lipid phase transition allowed the maintenance of the cell membrane in a relatively fluid state during freezing, thus facilitating water flux from the cell and the concomitant volume reduction following ice formation in the extracellular medium. In addition, the lipid phase transition of freeze-resistant cells occurred within a short temperature range, which could be ascribed to a reduced number of fatty acids, representing more than 80% of the total. This short lipid phase transition could be associated with a limited phenomenon of lateral phase separation and membrane permeabilization. This work highlights that membrane phase transitions occurring during freeze-thawing play a fundamental role in the

Brief report: Lactobacillus bulgaricus GLB44 (Proviotic™ ) plus esomeprazole for Helicobacter pylori eradication: A pilot study.

Science.gov (United States)

Opekun, Antone R; Gonzales, Savannah A; Al-Saadi, Mahmoud A; Graham, David Y

2018-04-01

Recent studies of Lactobacillus delbrueckii subsp. bulgaricus GLB44 plus a proton-pump inhibitor (PPI) reported cures of more than 90% of patients with active Helicobacter pylori infections. To confirm the high H. pylori cure rates reported previously. A pilot study was done in healthy H. pylori-infected volunteers using 3-gram sachet (3 billion cells) of L. delbrueckii GLB44 plus 22.3 mg of esomeprazole b.i.d., for 14 days. The result was determined by urea breath testing 4 weeks after therapy. Stopping rules required for ending enrollment if less than 3 of the first 10 subjects were cured. Nine subjects were entered and because all failed to achieve negative urea breath test, the stopping rule required the study to end. We were unable to confirm reports of achieving a high H. pylori cure rate with L. delbrueckii GLB44 plus a PPI. © 2018 John Wiley & Sons Ltd.

Survival of Yogurt Bacteria in the Human Gut

OpenAIRE

Elli, Marina; Callegari, Maria Luisa; Ferrari, Susanna; Bessi, Elena; Cattivelli, Daniela; Soldi, Sara; Morelli, Lorenzo; Goupil Feuillerat, Nathalie; Antoine, Jean-Michel

2006-01-01

Whether Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus can be recovered after passage through the human gut was tested by feeding 20 healthy volunteers commercial yogurt. Yogurt bacteria were found in human feces, suggesting that they can survive transit in the gastrointestinal tract.

A mild pulsed electric field condition that improves acid tolerance, growth, and protease activity of Lactobacillus acidophilus LA-K and Lactobacillus delbrueckii subspecies bulgaricus LB-12.

Science.gov (United States)

Najim, N; Aryana, Kayanush J

2013-06-01

Pulsed electric field (PEF) processing involves the application of pulses of voltage for less than 1 s to fluid products placed between 2 electrodes. The effect of mild PEF on beneficial characteristics of probiotic bacteria Lactobacillus acidophilus and Lactobacillus delbrueckii ssp. bulgaricus is not clearly understood. The objective of this study was to determine the influence of mild PEF conditions on acid tolerance, growth, and protease activity of Lb. acidophilus LA-K and Lactobacillus delbrueckii ssp. bulgaricus LB-12. A pilot plant PEF system (OSU-4M; The Ohio State University, Columbus) was used. The PEF treatments were positive square unipolar pulse width of 3 µs, pulse period of 0.5s, electric field strength of 1 kV/cm, delay time of 20 µs, flow rate of 60 mL/min, and 40.5°C PEF treatment temperature. Both Lb. acidophilus LA-K and Lb. bulgaricus LB-12 subjected to mild PEF conditions were acid tolerant until the end of the 120 min of incubation, unlike the Lb. bulgaricus control, which was not acid tolerant after 30 min. The mild PEF-treated Lb. acidophilus LA-K and Lb. bulgaricus LB-12 reached the logarithmic phase of growth an hour earlier than the control. Mild PEF conditions studied significantly improved acid tolerance, exponential growth, and protease activity of both Lb. acidophilus LA-K and Lb. bulgaricus LB-12 compared with the control. The mild PEF conditions studied can be recommended for pretreating cultures to enhance these desirable attributes. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Screening for new brewing yeasts in the non-Saccharomyces sector with Torulaspora delbrueckii as model.

Science.gov (United States)

Michel, Maximilian; Kopecká, Jana; Meier-Dörnberg, Tim; Zarnkow, Martin; Jacob, Fritz; Hutzler, Mathias

2016-04-01

This study describes a screening system for future brewing yeasts focusing on non-Saccharomyces yeasts. The aim was to find new yeast strains that can ferment beer wort into a respectable beer. Ten Torulaspora delbrueckii strains were put through the screening system, which included sugar utilization tests, hop resistance tests, ethanol resistance tests, polymerase chain reaction fingerprinting, propagation tests, amino acid catabolism and anabolism, phenolic off-flavour tests and trial fermentations. Trial fermentations were analysed for extract reduction, pH drop, yeast concentration in bulk fluid and fermentation by-products. All investigated strains were able to partly ferment wort sugars and showed high tolerance to hop compounds and ethanol. One of the investigated yeast strains fermented all the wort sugars and produced a respectable fruity flavour and a beer of average ethanol content with a high volatile flavour compound concentration. Two other strains could possibly be used for pre-fermentation as a bio-flavouring agent for beers that have been post-fermented by Saccharomyces strains as a consequence of their low sugar utilization but good flavour-forming properties. Copyright © 2015 John Wiley & Sons, Ltd.

The yogurt amino acid profile's variation during the shelf-life.

Science.gov (United States)

Germani, A; Luneia, R; Nigro, F; Vitiello, V; Donini, L M; del Balzo, V

2014-01-01

To analyze the yogurt amino acid profile starting from marketing through the whole shelf-life. The evaluation of the proteolytic activity of Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus salivarius subsp. thermophilus, allows to deduce their vitality during the shelf-life period and within 45 days. Three types of full fats yogurts have been analyzed (a) natural white (b) sweet white and (c) whole fruit - in two stages: t0 (first day of shelf-life) and t1 (end of shelf-life). The proteins have been analyzed by the Kjeldahl method and the amino acid profile by HPLC. In natural yogurt a significant increase of the amount of free amino acids has been observed during the period of shelf-life (97%). In the sweetened full fats and fruit yogurt, instead, there is a lower increase of respectively 33% and 39% In whole milk natural yogurt, based on our data, the proteolytic activity seems to persist during the entire period of the shelf-life and this can be considered an index of bacterial survival, especially of Lactobacillus delbrueckii subsp. bulgaricus during the marketing process.

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African Journals Online (AJOL)

Eco-friendly synthesis of silver nanoparticles using Lactobacillus delbrueckii subsp. bulgaricus isolated from kindrimo (locally fermented milk) in Kano State, Nigeria Abstract PDF · Vol 10, No 1 (2017): Special Conference Edition - Articles Microbiological evaluation of shelflife indices of fermented African locust bean cake ...

Survival of Yogurt Bacteria in the Human Gut

Science.gov (United States)

Elli, Marina; Callegari, Maria Luisa; Ferrari, Susanna; Bessi, Elena; Cattivelli, Daniela; Soldi, Sara; Morelli, Lorenzo; Goupil Feuillerat, Nathalie; Antoine, Jean-Michel

2006-01-01

Whether Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus can be recovered after passage through the human gut was tested by feeding 20 healthy volunteers commercial yogurt. Yogurt bacteria were found in human feces, suggesting that they can survive transit in the gastrointestinal tract. PMID:16820518

Use of Torulaspora delbrueckii Co-fermentation With Two Saccharomyces cerevisiae Strains With Different Aromatic Characteristic to Improve the Diversity of Red Wine Aroma Profile.

Science.gov (United States)

Zhang, Bo-Qin; Luan, Yu; Duan, Chang-Qing; Yan, Guo-Liang

2018-01-01

The use of selected Saccharomyces and non- Saccharomyces strains as mixed starters has advantages over pure fermentation due to achieving wine products with distinctive and diversified aroma expected by consumers. To obtain a way to improve the aroma diversity and increase the differentiation of wine product, in this study, the aromatic effect of multi-culture of indigenous Torulaspora delbrueckii ( TD 12), simultaneous and sequential inoculation with two Saccharomyces strains (indigenous icewine yeast SC 45 and commercial yeast BDX) with different enological characteristics were investigated in laboratory-scale 20 L fermenter, respectively. The results showed that T. delbrueckii co-fermented with different S. cerevisiae strain could generate diversified physicochemical and aromatic quality of wine as evidenced by PCA. Mixed fermentation of SC 45/ TD 12 produced higher contents of higher alcohol (3-methyl-1-pentanol and phenylethyl alcohol), ethyl esters (ethyl decanoate and ethyl butanoate), terpenes and phenylacetaldehyde with less fatty acids (hexanoic acid, octanoic acid) and acetic acid, while BDX/ TD 12 generated more C 6 alcohol (1-hexanol) and acetate esters (ethyl acetate and isoamyl acetate). Compared to simultaneous inoculation, sequential inoculation could achieve higher aroma diversity, and generate higher intensity of fruity, flowery and sweet attributes of wine as assessed by calculating the odor activity values. The different S. cerevisiae strain and inoculation method in alcoholic fermentation could further influence the formations of aromatic compounds in malolactic fermentation. Our results highlighted the importance of S. cerevisiae strain in shaping the aromatic quality of wine in mixed fermentation, and also suggested that using different S. cerevisiae strains with distinct aromatic characteristics co-fermentation with specific non- Saccharomyces strain is a potential way to increase the aromatic diversity and quality of wine product, which

Use of Torulaspora delbrueckii Co-fermentation With Two Saccharomyces cerevisiae Strains With Different Aromatic Characteristic to Improve the Diversity of Red Wine Aroma Profile

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Bo-Qin Zhang

2018-04-01

Full Text Available The use of selected Saccharomyces and non-Saccharomyces strains as mixed starters has advantages over pure fermentation due to achieving wine products with distinctive and diversified aroma expected by consumers. To obtain a way to improve the aroma diversity and increase the differentiation of wine product, in this study, the aromatic effect of multi-culture of indigenous Torulaspora delbrueckii (TD12, simultaneous and sequential inoculation with two Saccharomyces strains (indigenous icewine yeast SC45 and commercial yeast BDX with different enological characteristics were investigated in laboratory-scale 20 L fermenter, respectively. The results showed that T. delbrueckii co-fermented with different S. cerevisiae strain could generate diversified physicochemical and aromatic quality of wine as evidenced by PCA. Mixed fermentation of SC45/TD12 produced higher contents of higher alcohol (3-methyl-1-pentanol and phenylethyl alcohol, ethyl esters (ethyl decanoate and ethyl butanoate, terpenes and phenylacetaldehyde with less fatty acids (hexanoic acid, octanoic acid and acetic acid, while BDX/TD12 generated more C6 alcohol (1-hexanol and acetate esters (ethyl acetate and isoamyl acetate. Compared to simultaneous inoculation, sequential inoculation could achieve higher aroma diversity, and generate higher intensity of fruity, flowery and sweet attributes of wine as assessed by calculating the odor activity values. The different S. cerevisiae strain and inoculation method in alcoholic fermentation could further influence the formations of aromatic compounds in malolactic fermentation. Our results highlighted the importance of S. cerevisiae strain in shaping the aromatic quality of wine in mixed fermentation, and also suggested that using different S. cerevisiae strains with distinct aromatic characteristics co-fermentation with specific non-Saccharomyces strain is a potential way to increase the aromatic diversity and quality of wine product, which

Use of Torulaspora delbrueckii Co-fermentation With Two Saccharomyces cerevisiae Strains With Different Aromatic Characteristic to Improve the Diversity of Red Wine Aroma Profile

Science.gov (United States)

Zhang, Bo-Qin; Luan, Yu; Duan, Chang-Qing; Yan, Guo-Liang

2018-01-01

The use of selected Saccharomyces and non-Saccharomyces strains as mixed starters has advantages over pure fermentation due to achieving wine products with distinctive and diversified aroma expected by consumers. To obtain a way to improve the aroma diversity and increase the differentiation of wine product, in this study, the aromatic effect of multi-culture of indigenous Torulaspora delbrueckii (TD12), simultaneous and sequential inoculation with two Saccharomyces strains (indigenous icewine yeast SC45 and commercial yeast BDX) with different enological characteristics were investigated in laboratory-scale 20 L fermenter, respectively. The results showed that T. delbrueckii co-fermented with different S. cerevisiae strain could generate diversified physicochemical and aromatic quality of wine as evidenced by PCA. Mixed fermentation of SC45/TD12 produced higher contents of higher alcohol (3-methyl-1-pentanol and phenylethyl alcohol), ethyl esters (ethyl decanoate and ethyl butanoate), terpenes and phenylacetaldehyde with less fatty acids (hexanoic acid, octanoic acid) and acetic acid, while BDX/TD12 generated more C6 alcohol (1-hexanol) and acetate esters (ethyl acetate and isoamyl acetate). Compared to simultaneous inoculation, sequential inoculation could achieve higher aroma diversity, and generate higher intensity of fruity, flowery and sweet attributes of wine as assessed by calculating the odor activity values. The different S. cerevisiae strain and inoculation method in alcoholic fermentation could further influence the formations of aromatic compounds in malolactic fermentation. Our results highlighted the importance of S. cerevisiae strain in shaping the aromatic quality of wine in mixed fermentation, and also suggested that using different S. cerevisiae strains with distinct aromatic characteristics co-fermentation with specific non-Saccharomyces strain is a potential way to increase the aromatic diversity and quality of wine product, which could provide

Use of non-saccharomyces Torulaspora delbrueckii yeast strains in winemaking and brewing

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Tataridis Panagiotis

2013-01-01

Full Text Available Selected Saccharomyces yeast strains have been used for more than 150 years in brewing and for several decades in winemaking. They are necessary in brewing because of the boiling of the wort, which results in the death of all yeast cells, with the exception of some Belgian style beers (ex. Lambic, where the wort is left to be colonized by indigenous yeast and bacteria from the environment and ferment naturally. In winemaking their use is also pertinent because they provide regular and timely fermentations, inhibit the growth of indigenous spoilage microorganisms and contribute to the desired sensory characters. Even though the use of selected Saccharomyces strains provides better quality assurance in winemaking in comparison to the unknown microbial consortia in the must, it has been debated for a long time now whether the use of selected industrial Saccharomyces strains results in wines with less sensory complexity and “terroir” character. In previous decades, non-Saccharomyces yeasts were mainly considered as spoilage/problematic yeast, since they exhibited low fermentation ability and other negative traits. In the last decades experiments have shown that there are some non-Saccharomyces strains (Candida, Pichia, Kluyveromyces, Torulaspora, etc which, even though they are not able to complete the fermentation they can still be used in sequential inoculation-fermentation with Saccharomyces to increase sensory complexity of the wines. Through fermentation in a laboratory scale, we have observed that the overall effects of selected Torulaspora delbrueckii yeast strains, is highly positive, leading to products with pronounced sensory complexity and floral/fruity aroma in winemaking and brewing.

D-Lactic acid biosynthesis from biomass-derived sugars via Lactobacillus delbrueckii fermentation.

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Zhang, Yixing; Vadlani, Praveen V

2013-12-01

Poly-lactic acid (PLA) derived from renewable resources is considered to be a good substitute for petroleum-based plastics. The number of poly L-lactic acid applications is increased by the introduction of a stereocomplex PLA, which consists of both poly-L and D-lactic acid and has a higher melting temperature. To date, several studies have explored the production of L-lactic acid, but information on biosynthesis of D-lactic acid is limited. Pulp and corn stover are abundant, renewable lignocellulosic materials that can be hydrolyzed to sugars and used in biosynthesis of D-lactic acid. In our study, saccharification of pulp and corn stover was done by cellulase CTec2 and sugars generated from hydrolysis were converted to D-lactic acid by a homofermentative strain, L. delbrueckii, through a sequential hydrolysis and fermentation process (SHF) and a simultaneous saccharification and fermentation process (SSF). 36.3 g L(-1) of D-lactic acid with 99.8 % optical purity was obtained in the batch fermentation of pulp and attained highest yield and productivity of 0.83 g g(-1) and 1.01 g L(-1) h(-1), respectively. Luedeking-Piret model described the mixed growth-associated production of D-lactic acid with a maximum specific growth rate 0.2 h(-1) and product formation rate 0.026 h(-1), obtained for this strain. The efficient synthesis of D-lactic acid having high optical purity and melting point will lead to unique stereocomplex PLA with innovative applications in polymer industry.

Fermentation supernatants of Lactobacillus delbrueckii inhibit growth of human colon cancer cells and induce apoptosis through a caspase 3-dependent pathway.

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Wan, Ying; Xin, Yi; Zhang, Cuili; Wu, Dachang; Ding, Dapeng; Tang, Li; Owusu, Lawrence; Bai, Jing; Li, Weiling

2014-05-01

Probiotic bacteria are known to exert a wide range of beneficial effects on their animal hosts. Therefore, the present study explored the effect of the supernatants obtained from Lactobacillus delbrueckii fermentation (LBF) on colon cancer. The results indicated that the proliferation of LBF solution-treated colon cancer SW620 cells was arrested and accumulated in the G1 phase in a concentration-dependent manner. The LBF solution efficiently induced apoptosis through the intrinsic caspase 3-depedent pathway, with a corresponding decreased expression of Bcl-2. The activity of matrix metalloproteinase 9, which is associated with the invasion of colon cancer cells, was also decreased in the LBF-treated cells. In conclusion, the results demonstrate the antitumor effect of LBF in vitro and may contribute to the development of novel therapies for the treatment of colon cancer.

“PENTOYO” with a Fully Sequenced Lactobacillus pentosus KCA1 ...

African Journals Online (AJOL)

Purpose: To determine whether L. pentosus KCA1 can be used to create a new probiotic yogurt and the organism's duration of survival when stored at 4 oC. Methods: Mother cultures of Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus and L. pentosus KCA1 were prepared and subsequently ...

Microencapsulation of Lactobacillus helveticus and Lactobacillus delbrueckii using alginate and gellan gum.

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Rosas-Flores, Walfred; Ramos-Ramírez, Emma Gloria; Salazar-Montoya, Juan Alfredo

2013-10-15

Sodium alginate (SA) at 2% (w/v) and low acylated gellan gum (LAG) at 0.2% (w/v) were used to microencapsulate Lactobacillus helveticus and Lactobacillus delbrueckii spp lactis by employing the internal ionic gelation technique through water-oil emulsions at three different stirring rates: 480, 800 and 1200 rpm. The flow behavior of the biopolymer dispersions, the activation energy of the emulsion, the microencapsulation efficiency, the size distribution, the microcapsules morphology and the effect of the stirring rate on the culture viability were analyzed. All of the dispersions exhibited a non-Newtonian shear-thinning flow behavior because the apparent viscosity decreased in value when the shear rate was increased. The activation energy was calculated using the Arrhenius-like equation; the value obtained for the emulsion was 32.59 kJ/mol. It was observed that at 400 rpm, the microencapsulation efficiency was 92.83%, whereas at 800 and 1200 rpm, the stirring rates reduced the efficiency to 15.83% and 4.56%, respectively, evidencing the sensitivity of the microorganisms to the shear rate (13.36 and 20.05 s(-1)). Both optical and scanning electron microscopy (SEM) showed spherical microcapsules with irregular topography due to the presence of holes on its surface. The obtained size distribution range was modified when the stirring rate was increased. At 400 rpm, bimodal behavior was observed in the range of 20-420 μm; at 800 and 1200 rpm, the behavior became unimodal and the range was from 20 to 200 μm and 20 to 160 μm, respectively. Copyright © 2013 Elsevier Ltd. All rights reserved.

A selective medium for the enumeration and differentiation of Lactobacillus delbrueckii ssp. bulgaricus.

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Nwamaioha, Nwadiuto O; Ibrahim, Salam A

2018-06-01

Modified reinforced clostridial medium (mRCM) was developed and evaluated for the differential enumeration of Lactobacillus delbrueckii ssp. bulgaricus. Lactobacillus bulgaricus, an important species of lactic acid bacteria with health benefits, is used in the production of yogurt and other fermented foods. Our results showed that supplementing reinforced clostridial medium with 0.025% CaCl 2 , 0.01% uracil, and 0.2% Tween 80 (mRCM) significantly enhanced the growth rate of L. bulgaricus RR and ATCC 11842 strains as measured by the optical densities of these strains after 12 h of incubation at 42°C. The bacterial populations (plate count) of the RR and ATCC 11842 strains were 0.76 and 0.77 log cfu/g higher in mRCM than in de Man, Rogosa, and Sharpe and reinforced clostridial medium media, respectively. Conversely, the population counts for other bacterial species (Bifidobacterium, Lactobacillus rhamnosus, and Lactobacillus reuteri) were significantly inhibited in the mRCM medium. The addition of aniline blue dye to mRCM (mRCM-blue) improved the selectivity of L. bulgaricus in mixed lactic bacterial cultures compared with de Man, Rogosa, and Sharpe medium and lactic agar with regard to colony appearance and morphology. The mRCM-blue performed better than the conventional medium in culturing, enumerating, and differentiating L. bulgaricus. Therefore, mRCM-blue could be used as a selective medium to enhance the growth and differentiation of L. bulgaricus in order to meet the increasing demand for this beneficial species of bacteria. Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Production, optimization and characterization of lactic acid by Lactobacillus delbrueckii NCIM 2025 from utilizing agro-industrial byproduct (cane molasses).

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Srivastava, Abhinay Kumar; Tripathi, Abhishek Dutt; Jha, Alok; Poonia, Amrita; Sharma, Nitya

2015-06-01

In the present work Lactobacillus delbrueckii was used to utilize agro-industrial byproduct (cane molasses) for lactic acid production under submerged fermentation process. Screening of LAB was done by Fourier transform infra red spectroscopy (FTIR). Effect of different amino acids (DL-Phenylalanine, L-Lysine and DL-Aspartic acid) on the fermentation process was done by high performance liquid chromatography (HPLC). Central composite rotatable design (CCRD) was used to optimize the levels of three parameters viz. tween 80, amino acid and cane molasses concentration during fermentative production of lactic acid. Under optimum condition lactic acid production was enhanced from 55.89 g/L to 84.50 g/L. Further, validation showed 81.50 g/L lactic acid production. Scale up was done on 7.5 L fermentor. Productivity was found to be 3.40 g/L/h which was higher than previous studies with reduced fermentation time from 24 h to 12 h. Further characterization of lactic acid was done by FTIR.

Growth and activity of Bulgarian yogurt starter culture in iron-fortified milk.

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Simova, Emilina; Ivanov, Galin; Simov, Zhelyazko

2008-10-01

Bulgarian yogurts were manufactured and fortified with 8, 15 and 27 mg of iron kg(-1) of yogurt. The growth and acidifying activity of the starter culture bacteria Streptococcus thermophilus 13a and Lactobacillus delbrueckii subsp. bulgaricus 2-11 were monitored during milk fermentation and over 15 days of yogurt storage at 4 degrees C. Fortifying milk with iron did not affect significantly the growth of the starter culture during manufacture and storage of yogurt. Counts of yogurt bacteria at the end of fermentation of iron-fortified milks were between 2.1 x 10(10) and 4.6 x 10(10) CFU ml(-1), which were not significantly different from numbers in unfortified yogurts. In all batches of yogurt, the viable cell counts of S. thermophilus 13a were approximately three times higher than those of L. delbrueckii subsp. bulgaricus 2-11. Greater decrease in viable cell count over 15 days of storage was observed for S. thermophilus 13a compared to L. delbrueckii subsp. bulgaricus 2-11. Intensive accumulation of lactic acid was observed during incubation of milk and all batches reached pH 4.5 +/- 0.1 after 3.0 h. At the end of fermentation process, lactic acid concentrations in iron-fortified yogurts were between 6.9 +/- 0.4 and 7.3 +/- 0.5 g l(-1). The acidifying activity of starter culture bacteria in the control and iron-fortified milks was similar. There was no increase in oxidized, metallic and bitter off-flavors in iron-fortified yogurts compared to the control. Iron-fortified yogurts did not differ significantly in their sensorial, chemical and microbiological characteristics with unfortified yogurt, suggesting that yogurt is a suitable vehicle for iron fortification and that the ferrous lactate is an appropriate iron source for yogurt fortification.

Screening of Probiotic Activities of Forty-Seven Strains of Lactobacillus spp. by In Vitro Techniques and Evaluation of the Colonization Ability of Five Selected Strains in Humans

OpenAIRE

Jacobsen, C. N.; Rosenfeldt Nielsen, V.; Hayford, A. E.; Møller, P. L.; Michaelsen, K. F.; Pærregaard, A.; Sandström, B.; Tvede, M.; Jakobsen, M.

1999-01-01

The probiotic potential of 47 selected strains of Lactobacillus spp. was investigated. The strains were examined for resistance to pH 2.5 and 0.3% oxgall, adhesion to Caco-2 cells, and antimicrobial activities against enteric pathogenic bacteria in model systems. From the results obtained in vitro, five strains, Lactobacillus rhamnosus 19070-2, L. reuteri DSM 12246, L. rhamnosus LGG, L. delbrueckii subsp. lactis CHCC 2329, and L. casei subsp. alactus CHCC 3137, were selected for in vivo studi...

Molecular identification and cluster analysis of homofermentative thermophilic lactobacilli isolated from dairy products.

Science.gov (United States)

Andrighetto, C; De Dea, P; Lombardi, A; Neviani, E; Rossetti, L; Giraffa, G

1998-10-01

Twenty-five strains of thermophilic lactobacilli isolated from yoghurt and from semi-hard and hard cheeses (in parallel with nine type or reference strains) were identified and grouped according to their genetic relatedness. Strains were identified by sugar fermentation patterns using the "API 50 CHL" galleries, by species-specific DNA probes in dot-blot hybridization experiments, by amplification and restriction analysis of the 16S rRNA gene (ARDRA) and by polymerase chain reaction (PCR) using species-specific oligonucleotide primers. Strains were classified as Lactobacillus delbrueckii subsp. lactis and subsp. bulgaricus, L. helveticus, and L. acidophilus. Strains which were atypical by sugar fermentation patterns were also identified. Most of the strains could not be grouped using carbohydrate fermentation profiles. PCR fingerprinting was used to identify DNA profiles for the 25 lactobacilli. Experimentally obtained PCR profiles enabled discrimination of all strains, which were grouped according to the similarities in their combined patterns. In general, the clustering of the strains corresponded well with species delineation obtained by molecular identification. The dendrogram of genetic relatedness enabled the unambiguous identification of most of the strains which were shown to be atypical by the sugar fermentation profile, except for a discrepancy in one L. delbrueckii subsp. lactis strain and one atypical Lactobacillus sp. strain.

Influence of casein hydrolysates on exopolysaccharide synthesis by Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus.

Science.gov (United States)

Zhang, Qingli; Yang, Bao; Brashears, Mindy M; Yu, Zhimin; Zhao, Mouming; Liu, Ning; Li, Yinjuan

2014-05-01

A lot of interesting research has been undertaken to enhance the yield of exopolysaccharides (EPS) produced by lactic acid bacteria (LAB). The objective of this study was to determine the influence of casein hydrolysates (CH) with molecular weight less than 3 kDa on cell viability, EPS synthesis and the enzyme activity involved in EPS synthesis during the co-culturing of Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus in MRS broth for 72 h at 37 ± 0.1 °C. The highest EPS yield (150.1 mg L⁻¹) was obtained on CH prepared with papain (CHP) at 48 h. At 24 h, EPS were composed of galactose, glucose and rhamnose in a molar ratio of 1.0:2.4:1.5. The monosaccharide composition changed with extension of the fermentation time. The activities of α-phosphoglucomutase, uridine 5'-diphosphate (UDP)-glucose pyrophosphorylase and UDP-galactose 4-epimerase were associated with EPS synthesis. Moreover, the activities of β-phosphoglucomutase and deoxythymadine 5'-diphosphate (dTDP)-glucose pyrophosphorylase involved in rhamnose synthesis were very low at the exponential growth phase and could not be detected during other given periods. The influence of different CH (<3 kDa) on LAB viability, EPS production, EPS monomeric composition and activity levels of key metabolic enzymes was distinct. Besides, their influence was related to the distribution of amino acids. © 2013 Society of Chemical Industry.

Differential enumeration of subpopulations in concentrated frozen and lyophilized cultures of Lactobacillus delbrueckii ssp. bulgaricus.

Science.gov (United States)

Shao, Yuyu; Wang, Zhaoxia; Bao, Qiuhua; Zhang, Heping

2017-11-01

Differential enumeration of subpopulations in concentrated frozen and lyophilized cultures of Lactobacillus delbrueckii ssp. bulgaricus ND02 derived from 2 propagation procedures was determined. The subpopulations consisted of 3 categories (physiological states): viable cells capable of forming colonies on agar plates (VC+), viable cells incapable of forming colonies on agar plates (VC-), widely referred to as viable but nonculturable (VBNC) cells, and nonviable or dead cells (NVC). Counts of VC+ were recorded using a conventional plate count procedure. A fluorescent vital staining procedure that discriminates between viable (VC+ and VC-) and NVC cells was used to determine the number of viable and nonviable cells. Both propagation procedures had 2 variables: in procedure (P)1, the propagation medium was rich in yeast extract (4.0%) and the pH was maintained at 5.7; in P2, the medium was devoid of yeast extract and the pH was maintained at 5.1. The results showed that post-propagation operations-concentration of cells by centrifugation and subsequent freezing or lyophilization of cell concentrate-induced different degrees of transience from VC+ to VC- states in cells derived from P1 and P2. Compared with cells derived from P2, cells from P1 were more labile to stress associated with centrifugation, freezing, and lyophilization, as revealed by differential counting. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

[Design of primers to DNA of lactic acid bacteria].

Science.gov (United States)

Lashchevskiĭ, V V; Kovalenko, N K

2003-01-01

Primers LP1-LP2 to the gene 16S rRNA have been developed, which permit to differentiate lactic acid bacteria: Lactobacillus plantarum, L. delbrueckii subsp. bulgaricus and Streptococcus salivarius subsp. thermophilus. The strain-specific and species-specific differentiations are possible under different annealing temperature. Additional fragments, which are synthesized outside the framework of gene 16S rRNA reading, provide for the strain-specific type of differentiation, and the fragment F864 read in the gene 16S rRNA permits identifying L. plantarum.

Sequential culture with Torulaspora delbrueckii and Saccharomyces cerevisiae and management of fermentation temperature to improve cherry wine quality.

Science.gov (United States)

Sun, Shu Yang; Gong, Han Sheng; Zhao, Yu Ping; Liu, Wen Li; Jin, Cheng Wu

2016-04-01

There has been limited research on the use of non-Saccharomyces yeasts for the production of cherry wines. This work used an autochthonous Torulaspora delbrueckii strain 49 (TD49) in association with a commercial S. cerevisiae RC212 yeast, to investigate the effect of multi-starter culture (sequential inoculation and simultaneous inoculation) and fermentation temperature on the quality of cherry wines. Both TD49 and RC212 proliferated during alcoholic fermentation (AF) under sequential inoculation conditions, whereas in the case of simultaneous inoculation, TD49 increased slowly at first and then declined sharply near the fermentation end. The analytical profile showed that both mixed fermentations produced lower levels of volatile acidy and higher levels of aromatic compounds than those from RC212 mono-culture. During sensory analysis, wines from sequential fermentation obtained the highest score, mainly due to the higher intensity in 'fruity' and 'floral' characters. As for the influence of temperature, a low temperature (20 °C) enhanced TD49 persistence during AF, but the sensory quality decreased anyway; 30 °C resulted in decreases in most measured descriptors. Therefore, 25 °C was selected as the best culture temperature. TD49/RC212 sequential inoculation and fermentation at 25 °C significantly enhanced the cherry wine quality. © 2015 Society of Chemical Industry.

Compositional characteristics of commercial yoghurt based on quantitative determination of viable lactic acid bacteria

Directory of Open Access Journals (Sweden)

Niketić Gordana B.

2009-01-01

Full Text Available Yoghurt quality is particularly difficult to standardize because of the many forms, varieties, manufacturing methods, ingredients and consumer preferences that exist. Since these factors will always play an important role, it is unlikely that a uniform yoghurt quality concept will ever emerge, such as has been developed for other dairy products. There are a number of common denominators, however that have bearing on yoghurt quality. Since a number of producers are recognized within the broad category entitled yoghurt. This situation makes yoghurt an interesting, challenging, but also a confusing area to work in. The present investigation was undertaken to isolate from commercial yoghurt the strains involved in its manufacture and determine the characteristics of Streptococcus thermophilus and Lactobacillus delbrueckii subsp.bulgaricus. This study is concerned with the lactic acid bacteria (L.delbrueckii subsp. bulgaricus and S. thermophilus growth in yoghurt from involving different procedures and with the determination of the number of lactic acid bacteria in dependence of the temperature and acidity in the period of storage. Predominant samples of yoghurt were with 11-107/ml lactic acid lactococci (44.28%.

Оценка влияния экзополисахаридов молочнокислых бактерий рода Lactobacillus на фагоцитарную активность макрофагов белых мышей

OpenAIRE

Правдивцева, М.; Горельникова, Е.; Абросимова, О.; Карпунина, Л.

2011-01-01

Показано влияние экзополисахаридов молочнокислых бактерий лаксаранов 1596, 1936, Z, выделенных из культур Lactobacillus delbrueckii subsp. delbrueckii B-1596, L. delbrueckii B-1936 и L. delbrueckii ssp. bulgaricus, на фагоцитарную активность альвеолярных и перитонеальных макрофагов мышей. Установлено, что наибольшее стимулирующее воздействие на перитонеальные и альвеолярные макрофаги оказывает лаксаран Z....

A Novel Glutamyl (Aspartyl)-Specific Aminopeptidase A from Lactobacillus delbrueckii with Promising Properties for Application.

Science.gov (United States)

Stressler, Timo; Ewert, Jacob; Merz, Michael; Funk, Joshua; Claaßen, Wolfgang; Lutz-Wahl, Sabine; Schmidt, Herbert; Kuhn, Andreas; Fischer, Lutz

2016-01-01

Lactic acid bacteria (LAB) are auxotrophic for a number of amino acids. Thus, LAB have one of the strongest proteolytic systems to acquit their amino acid requirements. One of the intracellular exopeptidases present in LAB is the glutamyl (aspartyl) specific aminopeptidase (PepA; EC 3.4.11.7). Most of the PepA enzymes characterized yet, belonged to Lactococcus lactis sp., but no PepA from a Lactobacillus sp. has been characterized so far. In this study, we cloned a putative pepA gene from Lb. delbrueckii ssp. lactis DSM 20072 and characterized it after purification. For comparison, we also cloned, purified and characterized PepA from Lc. lactis ssp. lactis DSM 20481. Due to the low homology between both enzymes (30%), differences between the biochemical characteristics were very likely. This was confirmed, for example, by the more acidic optimum pH value of 6.0 for Lb-PepA compared to pH 8.0 for Lc-PepA. In addition, although the optimum temperature is quite similar for both enzymes (Lb-PepA: 60°C; Lc-PepA: 65°C), the temperature stability after three days, 20°C below the optimum temperature, was higher for Lb-PepA (60% residual activity) than for Lc-PepA (2% residual activity). EDTA inhibited both enzymes and the strongest activation was found for CoCl2, indicating that both enzymes are metallopeptidases. In contrast to Lc-PepA, disulfide bond-reducing agents such as dithiothreitol did not inhibit Lb-PepA. Finally, Lb-PepA was not product-inhibited by L-Glu, whereas Lc-PepA showed an inhibition.

A Novel Glutamyl (Aspartyl-Specific Aminopeptidase A from Lactobacillus delbrueckii with Promising Properties for Application.

Directory of Open Access Journals (Sweden)

Timo Stressler

Full Text Available Lactic acid bacteria (LAB are auxotrophic for a number of amino acids. Thus, LAB have one of the strongest proteolytic systems to acquit their amino acid requirements. One of the intracellular exopeptidases present in LAB is the glutamyl (aspartyl specific aminopeptidase (PepA; EC 3.4.11.7. Most of the PepA enzymes characterized yet, belonged to Lactococcus lactis sp., but no PepA from a Lactobacillus sp. has been characterized so far. In this study, we cloned a putative pepA gene from Lb. delbrueckii ssp. lactis DSM 20072 and characterized it after purification. For comparison, we also cloned, purified and characterized PepA from Lc. lactis ssp. lactis DSM 20481. Due to the low homology between both enzymes (30%, differences between the biochemical characteristics were very likely. This was confirmed, for example, by the more acidic optimum pH value of 6.0 for Lb-PepA compared to pH 8.0 for Lc-PepA. In addition, although the optimum temperature is quite similar for both enzymes (Lb-PepA: 60°C; Lc-PepA: 65°C, the temperature stability after three days, 20°C below the optimum temperature, was higher for Lb-PepA (60% residual activity than for Lc-PepA (2% residual activity. EDTA inhibited both enzymes and the strongest activation was found for CoCl2, indicating that both enzymes are metallopeptidases. In contrast to Lc-PepA, disulfide bond-reducing agents such as dithiothreitol did not inhibit Lb-PepA. Finally, Lb-PepA was not product-inhibited by L-Glu, whereas Lc-PepA showed an inhibition.

Combining selected immunomodulatory Propionibacterium freudenreichii and Lactobacillus delbrueckii strains: Reverse engineering development of an anti-inflammatory cheese.

Science.gov (United States)

Plé, Coline; Breton, Jérôme; Richoux, Romain; Nurdin, Marine; Deutsch, Stéphanie-Marie; Falentin, Hélène; Hervé, Christophe; Chuat, Victoria; Lemée, Riwanon; Maguin, Emmanuelle; Jan, Gwénaël; Van de Guchte, Maarten; Foligné, Benoit

2016-04-01

Inflammatory bowel disease (IBD) constitutes a growing public health concern in western countries. Bacteria with anti-inflammatory properties are lacking in the dysbiosis accompanying IBD. Selected strains of probiotic bacteria with anti-inflammatory properties accordingly alleviate symptoms and enhance treatment of ulcerative colitis in clinical trials. Such properties are also found in selected strains of dairy starters such as Propionibacterium freudenreichii and Lactobacillus delbrueckii (Ld). We thus investigated the possibility to develop a fermented dairy product, combining both starter and probiotic abilities of both lactic acid and propionic acid bacteria, designed to extend remissions in IBD patients. We developed a single-strain Ld-fermented milk and a two-strain P. freudenreichii and Ld-fermented experimental pressed cheese using strains previously selected for their anti-inflammatory properties. Consumption of these experimental fermented dairy products protected mice against trinitrobenzenesulfonic acid induced colitis, alleviating severity of symptoms, modulating local and systemic inflammation, as well as colonic oxidative stress and epithelial cell damages. As a control, the corresponding sterile dairy matrix failed to afford such protection. This work reveals the probiotic potential of this bacterial mixture, in the context of fermented dairy products. It opens new perspectives for the reverse engineering development of anti-inflammatory fermented foods designed for target populations with IBD, and has provided evidences leading to an ongoing pilot clinical study in ulcerative colitis patients. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Cell growth and proteolytic activity of Lactobacillus acidophilus, Lactobacillus helveticus, Lactobacillus delbrueckii ssp. bulgaricus, and Streptococcus thermophilus in milk as affected by supplementation with peptide fractions.

Science.gov (United States)

Gandhi, Akanksha; Shah, Nagendra P

2014-12-01

The present investigation examined the effects of supplementation of milk peptide fractions produced by enzymatic hydrolysis on the fermentation of reconstituted skim milk (RSM). Changes in pH, cell growth, proteolytic activity, and angiotensin-converting enzyme (ACE)-inhibitory activity were monitored during fermentation of RSM by pure cultures of Lactobacillus acidophilus, Lactobacillus helveticus, Lactobacillus delbrueckii ssp. bulgaricus, and Streptococcus thermophilus. The study showed that supplementation with peptide fractions of different molecular weights did not significantly affect the bacterial growth in RSM. All bacteria showed an increased proteolytic activity in RSM supplemented with large peptides (>10 kDa), and L. helveticus in general exhibited the highest proteolytic activity among the bacteria studied. The ACE-inhibitory activity was observed to be the maximum in RSM supplemented with larger peptides (>10 kDa) for all bacteria. The results suggest that proteolysis by bacteria leads to increased production of ACE-inhibitory peptides compared to the supplemented peptides produced by enzymatic hydrolysis.

Structural characterization and antioxidant property of released exopolysaccharides from Lactobacillus delbrueckii ssp. bulgaricus SRFM-1.

Science.gov (United States)

Tang, Weizhi; Dong, Mingsheng; Wang, Weilu; Han, Shuo; Rui, Xin; Chen, Xiaohong; Jiang, Mei; Zhang, Qiuqin; Wu, Junjun; Li, Wei

2017-10-01

Three released exopolysaccharide fractions (r-EPS1, r-EPS2 and r-EPS3) were isolated from the fermented milk of Lactobacillus delbrueckii ssp. bulgaricus SRFM-1 and purified by anion exchange chromatography, and characterizations of the structures were conducted. The r-EPS1 and r-EPS2 were homogenous with the average molecular weights of 3.97×10 5 Da and 3.86×10 5 Da, respectively. Three r-EPS fractions were composed of galactose and glucose with a molar ratio of 1.23: 1.00, 1.33: 1.00 and 1.00: 1.34, respectively. Structural characterization indicated that the r-EPS1 contained a backbone of →6-β-d-Galp-(1→4)-β-d-Glcp-(1→4)-α-d-Galp-(1→4)-β-d-Galp-(1→6)-β-d-Galp-(1→4)-β-d-Glcp-(1→4)-α-d-Galp-(1→4)-β-d-Galp-(1→4)-α-d-Glcp-(1→, and had three branching points which existed in terminal with D-Glcp residues with α/β-d-(1→6) linkages. The r-EPS2 was composed of →6-β-d-Galp-(1→4)-β-d-Glcp-(1→6)-α-d-Galp-(1→ as the backbone chain with a branching point which also existed in terminal D-Glcp residue with β-(1→6) linkage. In addition, three r-EPS fractions exhibited strong scavenging activities on superoxide radical, hydroxyl radical, DPPH radical and chelating activity on ferrous ion, and their antioxidant activities decreased in the order of r-EPS1>r-EPS2>r-EPS3. Copyright © 2017 Elsevier Ltd. All rights reserved.

Long-Term Use of Probiotics Lactobacillus and Bifidobacterium Has a Prophylactic Effect on the Occurrence and Severity of Pouchitis: A Randomized Prospective Study

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Banasiewicz Tomasz

2014-01-01

Full Text Available Aim. The aim of the study was to assess the impact of the long-term use of the composite probiotics in patients after restorative proctocolectomy. Method. Forty-three patients (20 females and 23 males, aged 21 to 68 years after restorative proctocolectomy were included in the study. After randomization patients were divided into placebo group and treatment group with oral intake of probiotic containing Lactobacillus acidophilus, Lactobacillus delbrueckii subsp. bulgaricus, and Bifidobacterium bifidus. Patients were investigated during initial visit and during final visit after 9 months. All patients were subjected to standard clinical and endoscopic examination with microscopic study of the specimens. Concentrations of calprotectin and pyruvate kinase isoenzyme M2-PK were determined in all cases. Results. The average severity of pouchitis and the number of patients with pouchitis significantly decrease after 9 months of the probiotic taking. The concentrations of calprotectin and pyruvate kinase isoenzyme M2-PK significantly decreased after the therapy. Conclusions. Nine months of the probiotic treatment (Lactobacillus acidophilus, Lactobacillus delbrueckii subsp. bulgaricus, and Bifidobacterium bifidus reduced the number of patients with pouchitis, decreased the PDAI score, and also decreased the fecal pyruvate kinase and calprotectin. The long-term probiotics use is safe and well accepted and can be an effective method of the pouchitis prevention.

Factors affecting capsule size and production by lactic acid bacteria used as dairy starter cultures.

Science.gov (United States)

Hassan, A N; Frank, J F; Shalabi, S I

2001-02-28

The effects of sugar substrates on capsule size and production by some capsule-forming nonropy and ropy dairy starter cultures were studied. Test sugars (glucose, lactose, galactose, or sucrose) were used as a sole carbohydrate source and the presence of a capsule and its size were determined by using confocal scanning laser microscopy. Nonropy strains produced maximum capsule size when grown in milk. Strains that did not produce capsules in milk did not produce them in any other growth medium. Specific sugars required for capsule production were strain-dependent. Increasing lactose content of Elliker broth from 0.5 to 5% or adding whey protein or casein digest produced larger capsules. Whey protein concentrate stimulated production of larger capsules than did casamino acids or casitone. Some Streptococcus thermophilus strains produced capsules when grown on galactose only. Nonropy strains of Lactobacillus delbrueckii subsp. bulgaricus produced capsules on lactose, but not on glucose. A ropy strain of Lactobacillus delbrueckii subsp. bulgaricus produced a constant capsule size regardless of the growth medium. The ability of some strains of Streptococcus thermophilus to use galactose in capsule production could reduce browning of mozzarella cheese during baking by removing a source of reducing sugar. Media that do not support capsule production may improve cell harvesting.

A qualified presumption of safety approach for the safety assessment of Grana Padano whey starters.

Science.gov (United States)

Rossetti, Lia; Carminati, Domenico; Zago, Miriam; Giraffa, Giorgio

2009-03-15

A Qualified Presumption of Safety (QPS) approach was applied to dominant lactic acid bacteria (LAB) associated with Grana Padano cheese whey starters. Thirty-two strains belonging to Lactobacillus helveticus, Lactobacillus delbrueckii subsp. lactis, Streptococcus thermophilus, and Lactobacillus fermentum, and representing the overall genotypic LAB diversity associated with 24 previously collected whey starters [Rossetti, L., Fornasari, M.E., Gatti, M., Lazzi, C., Neviani, E., Giraffa, G., 2008. Grana Padano cheese whey starters: microbial composition and strain distribution. International Journal of Food Microbiology 127, 168-171], were analyzed. All L. helveticus, L. delbrueckii subsp. lactis, and S. thermophilus isolates were susceptible to four (i.e. vancomycin, gentamicin, tetracycline, and erythromycin) of the clinically most relevant antibiotics. One L. fermentum strain displayed phenotypic resistance to tetracycline (Tet(R)), with MIC of 32 microg/ml, and gentamycin (Gm(R)), with MIC of 32 microg/ml. PCR was applied to this strain to test the presence of genes tet(L), tet(M), tet(S), and aac(6')-aph(2')-Ia, which are involved in horizontal transfer of Tet(R) and Gm(R), respectively but no detectable amplification products were observed. According to QPS criteria, we conclude that Grana cheese whey starters do not present particular safety concerns.

Lactobacillus delbrueckii ssp. bulgaricus B-30892 can inhibit cytotoxic effects and adhesion of pathogenic Clostridium difficile to Caco-2 cells

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Banerjee Pratik

2009-04-01

Full Text Available Abstract Background Probiotic microorganisms are receiving increasing interest for use in the prevention, treatment, or dietary management of certain diseases, including antibiotic-associated diarrhea (AAD. Clostridium difficile is the most common cause of AAD and the resulting C. difficile – mediated infection (CDI, is potentially deadly. C. difficile associated diarrhea (CDAD is manifested by severe inflammation and colitis, mostly due to the release of two exotoxins by C. difficile causing destruction of epithelial cells in the intestine. The aim of this study was to determine the effect of probiotic bacteria Lactobacillus delbrueckii ssp. bulgaricus B-30892 (LDB B-30892 on C. difficile-mediated cytotoxicity using Caco-2 cells as a model. Methods Experiments were carried out to test if the cytotoxicity induced by C. difficile-conditioned-medium on Caco-2 cells can be altered by cell-free supernatant (CFS from LDB B-30892 in different dilutions (1:2 to 1:2048. In a similar experimental setup, comparative evaluations of other probiotic strains were made by contrasting the results from these strains with the results from LDB B-30892, specifically the ability to affect C. difficile induced cytotoxicity on Caco-2 monolayers. Adhesion assays followed by quantitative analysis by Giemsa staining were conducted to test if the CFSs from LDB B-30892 and other probiotic test strains have the capability to alter the adhesion of C. difficile to the Caco-2 monolayer. Experiments were also performed to evaluate if LDB B-30892 or its released components have any bactericidal effect on C. difficile. Results and discussion Co-culturing of LDB B-30892 with C. difficile inhibited the C. difficile-mediated cytotoxicity on Caco-2 cells. When CFS from LDB B-30892-C. difficile co-culture was administered (up to a dilution of 1:16 on Caco-2 monolayer, there were no signs of cytotoxicity. When CFS from separately grown LDB B-30892 was mixed with the cell-free toxin

Molecular and biochemical characterizations of human oral lactobacilli as putative probiotic candidates.

Science.gov (United States)

Strahinic, I; Busarcevic, M; Pavlica, D; Milasin, J; Golic, N; Topisirovic, L

2007-04-01

The objective of this study was to characterize the lactobacilli from the human oral cavity as a potential source of probiotic strains. Samples were collected from four different locations within the oral cavity: surface of healthy tooth, oral mucous membrane, surface of tooth decay and deep tooth decay. On the basis of morphological and biochemical properties eight categories were formed and 26 isolates were selected for further characterization. The isolates were determined as Lactobacillus sp. using primers specific for 16S rDNA. Sequencing of 16S rDNA genes and repetitive sequence-based polymerase chain reactions were used for determination to species and subspecies levels. Predominant species were Lactobacillus fermentum, Lactobacillus plantarum, Lactobacillus salivarius and Lactobacillus paracasei subsp. paracasei, while Lactobacillus acidophilus, Lactobacillus cellobiosus, Lactobacillus delbrueckii subsp. lactis and Lactobacillus gasseri were also present. The isolates Lactobacillus salivarius BGHO1, Lactobacillus fermentum BGHO36 and BGHO64, Lactobacillus gasseri BGHO89 and Lactobacillus delbrueckii subsp. lactis BGHO99 exhibited antagonistic action on the growth of Staphylococcus aureus, Enterococcus faecalis, Micrococcus flavus, Salmonella enteritidis, Streptococcus pneumoniae and Streptococcus mutans, but not on growth of Candida albicans. Moreover, the isolates L. salivarius BGHO1 and L. gasseri BGHO89 were tolerant to low pH and high concentration of bile salts. Taken together, these findings imply that L. salivarius BGHO1 and L. gasseri BGHO89 might be subjects for additional investigation as potential probiotic strains.

Drink fermented to the base of serum of milk and isolated soy protein / Bebida fermentada à base de soro de leite e isolado protéico de soja

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Ivone Yurika Mizubuti

2000-04-01

Full Text Available The whey and soy protein were used as substrate to obtain a basic beverage, fermented by yogurt culture (Lactobacillus delbrueckii subsp. buigaricus / Streptococcus salivarius subsp. thermophilus YC-180 and by probiotic culture (Lactobacillus acidophilus La-5. The formulation ( whey 10g/100mL; soy protein 2,4 g/100mL; fiber 0,5 g/100mL and sucrose 15 g/100mL was fermented separately, and mixed (1:1 to obtain the final fermented product with 0.72% (lactic acid acidity, pH 4.3 and lactic acid bacteria count of 2,0 x 108 cfu/mL, adequate for production of the proposed beverage.O soro de leite e o isolado protéico de soja foram utilizados para obtenção de uma bebida base, fermentada com cultura de iogurte (Lactobacillus delbrueckii subsp. bulgaricus / Streptococcus salivarius subsp. thermophilus YC - 180 e cultura probiótica (Lactobacillus acidophilus La-5. A formulação (soro de leite 10 g/100mL; isolado protéico de soja 2,4 g/100mL; fibras 0,5 g/100mL e sacarose 15 g/100mL indicou que procedendo-se a fermentação seguida de mistura na proporção de 1:1, produziu-se um produto final com acidez de 0,72% de ácido láctico; pH 4,3 e contagem de bactérias lácticas de 2,0 x 108 ufc/mL adequado para a obtenção da bebida proposta.

Exopolysaccharides from Lactobacillus delbrueckii OLL1073R-1 modulate innate antiviral immune response in porcine intestinal epithelial cells.

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Kanmani, Paulraj; Albarracin, Leonardo; Kobayashi, Hisakazu; Iida, Hikaru; Komatsu, Ryoya; Humayun Kober, A K M; Ikeda-Ohtsubo, Wakako; Suda, Yoshihito; Aso, Hisashi; Makino, Seiya; Kano, Hiroshi; Saito, Tadao; Villena, Julio; Kitazawa, Haruki

2018-01-01

Previous studies demonstrated that the extracellular polysaccharides (EPSs) produced by Lactobacillus delbrueckii OLL1073R-1 (LDR-1) improve antiviral immunity, especially in the systemic and respiratory compartments. However, it was not studied before whether those EPSs are able to beneficially modulate intestinal antiviral immunity. In addition, LDR-1-host interaction has been evaluated mainly with immune cells while its interaction with intestinal epithelial cells (IECs) was not addressed before. In this work, we investigated the capacity of EPSs from LDR-1 to modulate the response of porcine IECs (PIE cells) to the stimulation with the Toll-like receptor (TLR)-3 agonist poly(I:C) and the role of TLR2, TLR4, and TLR negative regulators in the immunoregulatory effect. We showed that innate immune response triggered by TLR3 activation in porcine IECs was differentially modulated by EPS from LDR-1. EPSs treatment induced an increment in the expression of interferon (IFN)-α and IFN-β in PIE cells after the stimulation with poly(I:C) as well as the expression of the antiviral factors MxA and RNase L. Those effects were related to the reduced expression of A20 in EPS-treated PIE cells. EPS from LDR-1 was also able to reduce the expression of IL-6 and proinflammatory chemokines. Although further in vivo studies are needed, our results suggest that these EPSs or a yogurt fermented with LDR-1 have potential to improve intestinal innate antiviral response and protect against intestinal viruses. Copyright © 2017 Elsevier Ltd. All rights reserved.

Application of propidium monoazide quantitative real-time PCR to quantify the viability of Lactobacillus delbrueckii ssp. bulgaricus.

Science.gov (United States)

Shao, Yuyu; Wang, Zhaoxia; Bao, Qiuhua; Zhang, Heping

2016-12-01

In this study, a combination of propidium monoazide (PMA) and quantitative real-time PCR (qPCR) was used to develop a method to determine the viability of cells of Lactobacillus delbrueckii ssp. bulgaricus ND02 (L. bulgaricus) that may have entered into a viable but nonculturable state. This can happen due to its susceptibility to cold shock during lyophilization and storage. Propidium monoazide concentration, PMA incubation time, and light exposure time were optimized to fully exploit the PMA-qPCR approach to accurately assess the total number of living L. bulgaricus ND02. Although PMA has little influence on living cells, when concentrations of PMA were higher than 30μg/mL the number of PCR-positive living bacteria decreased from 10 6 to 10 5 cfu/mL in comparison with qPCR enumeration. Mixtures of living and dead cells were used as method verification samples for enumeration by PMA-qPCR, demonstrating that this method was feasible and effective for distinguishing living cells of L. bulgaricus when mixed with a known number of dead cells. We suggest that several conditions need to be studied further before PMA-qPCR methods can be accurately used to distinguish living from dead cells for enumeration under more realistic sampling situations. However, this research provides a rapid way to enumerate living cells of L. bulgaricus and could be used to optimize selection of cryoprotectants in the lyophilization process and develop technologies for high cell density cultivation and optimal freeze-drying processes. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Lactobacillus delbrueckii ssp. bulgaricus B-30892 can inhibit cytotoxic effects and adhesion of pathogenic Clostridium difficile to Caco-2 cells

Science.gov (United States)

Banerjee, Pratik; Merkel, Glenn J; Bhunia, Arun K

2009-01-01

Background Probiotic microorganisms are receiving increasing interest for use in the prevention, treatment, or dietary management of certain diseases, including antibiotic-associated diarrhea (AAD). Clostridium difficile is the most common cause of AAD and the resulting C. difficile – mediated infection (CDI), is potentially deadly. C. difficile associated diarrhea (CDAD) is manifested by severe inflammation and colitis, mostly due to the release of two exotoxins by C. difficile causing destruction of epithelial cells in the intestine. The aim of this study was to determine the effect of probiotic bacteria Lactobacillus delbrueckii ssp. bulgaricus B-30892 (LDB B-30892) on C. difficile-mediated cytotoxicity using Caco-2 cells as a model. Methods Experiments were carried out to test if the cytotoxicity induced by C. difficile-conditioned-medium on Caco-2 cells can be altered by cell-free supernatant (CFS) from LDB B-30892 in different dilutions (1:2 to 1:2048). In a similar experimental setup, comparative evaluations of other probiotic strains were made by contrasting the results from these strains with the results from LDB B-30892, specifically the ability to affect C. difficile induced cytotoxicity on Caco-2 monolayers. Adhesion assays followed by quantitative analysis by Giemsa staining were conducted to test if the CFSs from LDB B-30892 and other probiotic test strains have the capability to alter the adhesion of C. difficile to the Caco-2 monolayer. Experiments were also performed to evaluate if LDB B-30892 or its released components have any bactericidal effect on C. difficile. Results and discussion Co-culturing of LDB B-30892 with C. difficile inhibited the C. difficile-mediated cytotoxicity on Caco-2 cells. When CFS from LDB B-30892-C. difficile co-culture was administered (up to a dilution of 1:16) on Caco-2 monolayer, there were no signs of cytotoxicity. When CFS from separately grown LDB B-30892 was mixed with the cell-free toxin preparation (CFT) of

Interactions among lactic acid starter and probiotic bacteria used for fermented dairy products.

Science.gov (United States)

Vinderola, C G; Mocchiutti, P; Reinheimer, J A

2002-04-01

Interactions among lactic acid starter and probiotic bacteria were investigated to establish adequate combinations of strains to manufacture probiotic dairy products. For this aim, a total of 48 strains of Streptococcus thermophilus, Lactobacillus delbrueckii subsp. bulgaricus, Lactococcus lactis, Lactobacillus acidophilus, Lactobacillus casei, and Bifidobacterium spp. (eight of each) were used. The detection of bacterial interactions was carried out using the well-diffusion agar assay, and the interactions found were further characterized by growth kinetics. A variety of interactions was demonstrated. Lb. delbrueckii subsp. bulgaricus was found to be able to inhibit S. thermophilus strains. Among probiotic cultures, Lb. acidophilus was the sole species that was inhibited by the others (Lb. casei and Bifidobacterium). In general, probiotic bacteria proved to be more inhibitory towards lactic acid bacteria than vice versa since the latter did not exert any effect on the growth of the former, with some exceptions. The study of interactions by growth kinetics allowed the setting of four different kinds of behaviors between species of lactic acid starter and probiotic bacteria (stimulation, delay, complete inhibition of growth, and no effects among them). The possible interactions among the strains selected to manufacture a probiotic fermented dairy product should be taken into account when choosing the best combination/s to optimize their performance in the process and their survival in the products during cold storage.

The production of exopolysaccharides by Lactobacillus delbrueckii subsp. bulgaricus

NARCIS (Netherlands)

Grobben, G.

1998-01-01

Extracellular polysaccharides (EPS) produced by lactic acid bacteria have gained great popularity in the food industry because of their thickening and stabilizing properties. Since lactic acid bacteria have the GRAS ( G enerally R ecognized

The potential of the endolysin Lysdb from Lactobacillus delbrueckii phage for combating Staphylococcus aureus during cheese manufacture from raw milk.

Science.gov (United States)

Guo, Tingting; Xin, YongPing; Zhang, Chenchen; Ouyang, Xudong; Kong, Jian

2016-04-01

Phage endolysins have received increased attention in recent times as potential antibacterial agents and the biopreservatives in food production processes. Staphylococcus aureus is one of the most common pathogens in bacterial food poisoning outbreaks. In this study, the endolysin Lysdb, one of the two-component cell lysis cassette of Lactobacillus delbrueckii phage phiLdb, was shown to possess a muramidase domain and catalytic sites with homology to Chalaropsis-type lysozymes. Peptidoglycan hydrolytic bond specificity determination revealed that Lysdb was able to cleave the 6-O-acetylated peptidoglycans present in the cell walls of S. aureus. Turbidity reduction assays demonstrated that Lysdb could effectively lyse the S. aureus live cells under acidic and mesothermal conditions. To further evaluate the ability of Lysdb as a potential antibacterial agent against S. aureus in cheese manufacture, Lactobacillus casei BL23 was engineered to constitutively deliver active Lysdb to challenge S. aureus in lab-scale cheese making from raw milk. Compared with the raw milk, the viable counts of S. aureus were reduced by 10(5)-fold in the cheese inoculated with the engineered L. casei strain during the fermentation process, and the pathogenic bacterial numbers remained at a low level (10(4) CFU/g) after 6 weeks of ripening at 10 °C. Taken together, all results indicated that the Lysdb has the function as an effective tool for combating S. aureus during cheese manufacture from raw milk.

Prevention by lactic acid bacteria of the oxidation of human LDL.

Science.gov (United States)

Terahara, M; Kurama, S; Takemoto, N

2001-08-01

Ether extracts of lactic acid bacteria were analyzed for prevention of the oxidation of erythrocyte membrane and human low-density lipoprotein in vivo. Streptococcus thermophilus 1131 and Lactobacillus delbrueckii subsp. bulgaricus 2038, yogurt starters, were chosen as test-strains, and ether extracts of these cultures were used as samples. Both strain 1131 and strain 2038 produced radical scavengers and inhibited oxidation of erythrocyte membranes and low-density lipoproteins. The antioxidative activity of strain 2038 was higher than that of strain 1131.

A new wine Torulaspora delbrueckii killer strain with broad antifungal activity and its toxin-encoding double-stranded RNA virus

Science.gov (United States)

Ramírez, Manuel; Velázquez, Rocío; Maqueda, Matilde; López-Piñeiro, Antonio; Ribas, Juan C.

2015-01-01

Wine Torulaspora delbrueckii strains producing a new killer toxin (Kbarr-1) were isolated and selected for wine making. They killed all the previously known Saccharomyces cerevisiae killer strains, in addition to other non-Saccharomyces yeasts. The Kbarr-1 phenotype is encoded by a medium-size 1.7 kb dsRNA, TdV-Mbarr-1, which seems to depend on a large-size 4.6 kb dsRNA virus (TdV-LAbarr) for stable maintenance and replication. The TdV-Mbarr-1 dsRNA was sequenced by new generation sequencing techniques. Its genome structure is similar to those of S. cerevisiae killer M dsRNAs, with a 5′-end coding region followed by an internal A-rich sequence and a 3′-end non-coding region. Mbarr-1 RNA positive strand carries cis acting signals at its 5′ and 3′ termini for transcription and replication respectively, similar to those RNAs of yeast killer viruses. The ORF at the 5′ region codes for a putative preprotoxin with an N-terminal secretion signal, potential Kex2p/Kexlp processing sites, and N-glycosylation sites. No relevant sequence identity was found either between the full sequence of Mbarr-1 dsRNA and other yeast M dsRNAs, or between their respective toxin-encoded proteins. However, a relevant identity of TdV-Mbarr-1 RNA regions to the putative replication and packaging signals of most of the M-virus RNAs suggests that they are all evolutionarily related. PMID:26441913

Growth and acid production of Lactobacillus delbrueckii ssp. bulgaricus ATCC 11842 in the fermentation of algal carcass.

Science.gov (United States)

Li, C; Zhang, G F; Mao, X; Wang, J Y; Duan, C Y; Wang, Z J; Liu, L B

2016-06-01

Algal carcass is a low-value byproduct of algae after its conversion to biodiesel. Dried algal carcass is rich in protein, carbohydrate, and multiple amino acids, and it is typically well suited for growth and acid production of lactic acid bacteria. In this study, Lactobacillus delbrueckii ssp. bulgaricus ATCC 11842 was used to ferment different algal carcass media (ACM), including 2% ACM, 2% ACM with 1.9% glucose (ACM-G), and 2% ACM with 1.9% glucose and 2g/L amino acid mixture (ACM-GA). Concentrations of organic acids (lactic acid and acetic acid), acetyl-CoA, and ATP were analyzed by HPLC, and activities of lactate dehydrogenase (LDH), acetokinase (ACK), pyruvate kinase (PK), and phosphofructokinase (PFK) were determined by using a chemical approach. The growth of L. bulgaricus cells in ACM-GA was close to that in the control medium (de Man, Rogosa, and Sharpe). Lactic acid and acetic acid contents were greatly reduced when L. bulgaricus cells were grown in ACM compared with the control medium. Acetyl-CoA content varied with organic acid content and was increased in cells grown in different ACM compared with the control medium. The ATP content of L. bulgaricus cells in ACM was reduced compared with that of cells grown in the control medium. Activities of PFK and ACK of L. bulgaricus cells grown in ACM were higher and those of PK and LDH were lower compared with the control. Thus, ACM rich in nutrients may serve as an excellent substrate for growth by lactic acid bacteria, and addition of appropriate amounts of glucose and amino acids can improve growth and acid production. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Exopolysaccharides from lactic acid bacteria as corrosion inhibitors

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Ignatova-Ivanova, Tsveteslava; Ivanov, Radoslav

2016-03-01

Bacterial EPSs (exopolysaccharides) are believed to play an important role in the environment by promoting survival strategies such as bacterial attachment to surfaces and nutrient trapping, which facilitate processes of biofilm formation and development. These microbial biofilms have been implicated in corrosion of metals, bacterial attachment to prosthetic devices, fouling of heat exchange surfaces, toxicant immobilization, and fouling of ship hulls. In this paper, data on EPS production and the effect of EPS on corrosion of steel produced by Lactobacillus sp. are presented and discussed. Lactobacillus delbrueckii K27, Lactobacillus delbrueckii B8, Lactobacillus delbrueckii KO43, Lactobacillus delbrueckii K3, Lactobacillus delbrueckii K15 and Lactobacillus delbrueckii K17 was obtained from Collection of Department of General and Applied Microbiology, Sofia University. It was tested for its ability to produce exopolysaccharides when cultivated in a media containing 10% sucrose, 10% lacose and 10% maltose. The study of the corrosive stability of steel samples was conducted on the gravimetrique method. The rate of corrosion, the degree of protection, and coefficient of protection have been calculated. The structure of layer over steel plates was analysed by SEM (scanning electron microscopy) JSM 5510. It could be underlined that 10% sucrose, 10% lactose and 10% maltose in the media stimulated the process of protection of corrosion.

Effect of the absence of the CcpA gene on growth, metabolic production, and stress tolerance in Lactobacillus delbrueckii ssp. bulgaricus.

Science.gov (United States)

Li, C; Sun, J W; Zhang, G F; Liu, L B

2016-01-01

The catabolite control protein A (CcpA) is a kind of multi-effect regulatory protein. In the study, the effect of the inactivation of CcpA and aerobic conditions on the growth, metabolic production, and stress tolerance to heat, oxidative, and cold stresses in Lactobacillus delbrueckii ssp. bulgaricus was investigated. Results showed that inactivation of CcpA distinctly hindered growth. Total lactic acid concentration was significantly lower in aerobiosis for both strains and was lower for the mutant strain than L. bulgaricus. Acetic acid production from the mutant strain was higher than L. bulgaricus in aerobiosis compared with anaerobiosis. Enzyme activities, lactate dehydrogenase (LDH), phosphate fructose kinase (PFK), pyruvate kinase (PK), and pyruvic dehydrogenase (PDH), were significantly lower in the mutant strain than L. bulgaricus. The diameters of inhibition zone were 13.59 ± 0.02 mm and 9.76 ± 0.02 mm for L. bulgaricus in anaerobiosis and aerobiosis, respectively; and 8.12 ± 0.02 mm and 7.38 ± 0.02 mm for the mutant in anaerobiosis and aerobiosis, respectively. For both strains, cells grown under aerobic environment possess more stress tolerance. This is the first study in which the CcpA-negative mutant of L. bulgaricus is constructed and the effect of aerobic growth on stress tolerance of L. bulgaricus is evaluated. Although aerobic cultivation does not significantly improve growth, it does improve stress tolerance. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Exploring process dynamics by near infrared spectroscopy in lactic fermentations

DEFF Research Database (Denmark)

Svendsen, Carina; Cieplak, Tomasz; van der Berg, Franciscus Winfried J

2016-01-01

In the industrial production of yoghurt, measurement of pH is normally the only in-line technique applied as a real-time monitoring signalfor following the dynamics during the fermentation process. However, every dairy company would benefit from an in-line technique giving information about...... the chemical composition, physical/textural properties and/or microbial contamination. In this study lactic fermentation batches with the starter bacteria Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus are explored by in-line near infrared (NIR) spectroscopy. The dynamics obtained...

Exopolysaccharides from lactic acid bacteria as corrosion inhibitors

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Ignatova-Ivanova Tsveteslava

2016-03-01

Full Text Available Bacterial EPSs (exopolysaccharides are believed to play an important role in the environment by promoting survival strategies such as bacterial attachment to surfaces and nutrient trapping, which facilitate processes of biofilm formation and development. These microbial biofilms have been implicated in corrosion of metals, bacterial attachment to prosthetic devices, fouling of heat exchange surfaces, toxicant immobilization, and fouling of ship hulls. In this paper, data on EPS production and the effect of EPS on corrosion of steel produced by Lactobacillus sp. are presented and discussed. Lactobacillus delbrueckii K27, Lactobacillus delbrueckii B8, Lactobacillus delbrueckii KO43, Lactobacillus delbrueckii K3, Lactobacillus delbrueckii K15 and Lactobacillus delbrueckii K17 was obtained from Collection of Department of General and Applied Microbiology, Sofia University. It was tested for its ability to produce exopolysaccharides when cultivated in a media containing 10% sucrose, 10% lacose and 10% maltose. The study of the corrosive stability of steel samples was conducted on the gravimetrique method. The rate of corrosion, the degree of protection, and coefficient of protection have been calculated. The structure of layer over steel plates was analysed by SEM (scanning electron microscopy JSM 5510. It could be underlined that 10% sucrose, 10% lactose and 10% maltose in the media stimulated the process of protection of corrosion.

Conserved S-Layer-Associated Proteins Revealed by Exoproteomic Survey of S-Layer-Forming Lactobacilli

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Johnson, Brant R.; Hymes, Jeffrey; Sanozky-Dawes, Rosemary; Henriksen, Emily DeCrescenzo

2015-01-01

The Lactobacillus acidophilus homology group comprises Gram-positive species that include L. acidophilus, L. helveticus, L. crispatus, L. amylovorus, L. gallinarum, L. delbrueckii subsp. bulgaricus, L. gasseri, and L. johnsonii. While these bacteria are closely related, they have varied ecological lifestyles as dairy and food fermenters, allochthonous probiotics, or autochthonous commensals of the host gastrointestinal tract. Bacterial cell surface components play a critical role in the molecular dialogue between bacteria and interaction signaling with the intestinal mucosa. Notably, the L. acidophilus complex is distinguished in two clades by the presence or absence of S-layers, which are semiporous crystalline arrays of self-assembling proteinaceous subunits found as the outermost layer of the bacterial cell wall. In this study, S-layer-associated proteins (SLAPs) in the exoproteomes of various S-layer-forming Lactobacillus species were proteomically identified, genomically compared, and transcriptionally analyzed. Four gene regions encoding six putative SLAPs were conserved in the S-layer-forming Lactobacillus species but not identified in the extracts of the closely related progenitor, L. delbrueckii subsp. bulgaricus, which does not produce an S-layer. Therefore, the presence or absence of an S-layer has a clear impact on the exoproteomic composition of Lactobacillus species. This proteomic complexity and differences in the cell surface properties between S-layer- and non-S-layer-forming lactobacilli reveal the potential for SLAPs to mediate intimate probiotic interactions and signaling with the host intestinal mucosa. PMID:26475115

Yoghurt production from camel (Camelus dramedarius milk fortified with samphire molasses and different colloids

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Nazan Kavas

2016-01-01

Full Text Available In this study, yoghurt was produced from camel (Camelus dramedarius milk with whey protein isolate (3 % w/v and fortified with 3 % (w/v traditional samphire molasses (TSM (YTSM, 3 % (w/v TSM+0.1% (w/v κ-carrageenan (YTSMC or 3 % (w/v TSM+0.05 % (w/v xanthan gum (YTSMX. In yoghurt samples, physical-chemical properties, texture, color and sensory analysis were determined on the 1st, 5th, 10th and 14th days of storage, while total phenolics (TF levels were determined on the 14th, 24th, 32nd, 48th, 72nd, 120th, 240th and 336th hours of storage. In all samples during storage, hardness and viscosity increased along with the acidity increase, although the increases in YTSM and YTSMC were lower than in YTSMX. In YTSMX, in spite of the increase in acidity after the 1st day, serum separation was very low while viscosity and hardness values were higher compared to the other samples. YTSMX was found to be superior to the other samples in terms of physicochemical, textural, microbiological and sensory properties. Total phenolic contents and L*a*b* levels increased in all samples throughout storage, the highest values of which were in YTSMX. After the 5th day of the storage, Lactobacillus delbrueckii subsp. bulgaricus became the dominant microbial flora. After the 5th day of storage, Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus levels were highest in YTSMX.

Kinetic studies of the action of Lactacin F, a bacteriocin produced by Lactobacillus johnsonii that forms poration complexes in the cytoplasmic membrane.

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Abee, T.; Klaenhammer, T.R.; Letellier, L.

1994-01-01

The bacteriocin lactacin F is bactericidal against Lactobacillus delbrueckii, Lactobacillus helveticus, and Enterococcus faecalis. Activity against L. delbrueckii was recently shown to be dependent on two peptides, LafA and LafX, which are encoded within the lactacin F operon (T. R. Klaenhammer,

Lactic Acid Yield Using Different Bacterial Strains, Its Purification, and Polymerization through Ring-Opening Reactions

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F. G. Orozco

2014-01-01

Full Text Available Laboratory-scale anaerobic fermentation was performed to obtain lactic acid from lactose, using five lactic acid bacteria: Lactococcus lactis, Lactobacillus bulgaricus, L. delbrueckii, L. plantarum, and L. delbrueckii lactis. A yield of 0.99 g lactic acid/g lactose was obtained with L. delbrueckii, from which a final concentration of 80.95 g/L aqueous solution was obtained through microfiltration, nanofiltration, and inverse osmosis membranes. The lactic acid was polymerized by means of ring-opening reactions (ROP to obtain poly-DL-lactic acid (PDLLA, with a viscosity average molecular weight (Mv of 19,264 g/mol.

An in vitro investigation of immunomodulatory properties of Lactobacillus plantarum and L. delbrueckii cells and their extracellular polysaccharides.

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Kishimoto, Mana; Nomoto, Ryohei; Mizuno, Masashi; Osawa, Ro

2017-01-01

Many probiotic lactobacilli and their extracellular polysaccharides (EPS) have beneficial immunological properties. However, it is unclear how they elicit the host immune response. We thus investigated the immunological properties of UV-killed Lactobacillus delbrueckii TU-1 and L. plantarum KM-9 cells as well as their extracellular polysaccharides (EPSs). High-performance liquid chromatography and ion exchange chromatography analyses showed that their EPSs differ in sugar composition and sugar fractionation. The immunological properties were evaluated in a semi-intestinal model using a Transwell co-culture system that employed human intestinal epithelial (Caco-2) cells on the apical side and murine macrophage (RAW264.7) cells on the basolateral side. The UV-killed cells and EPSs were added to the apical side to allow direct contact with Caco-2 cells and incubated for 6 hr. After incubation, the amounts of tumor necrosis factor-α and several cytokines released by RAW264.7 or Caco-2 cells were quantified by cytotoxic activity on L929 cells (murine fibrosarcoma cell line) and quantitative reverse-transcriptase PCR. We found that the UV-killed cells and their EPSs had immunological effects on RAW264.7 cells via Caco-2 cells. The RAW264.7 cells showed different cytokine production profiles when treated with UV-killed cells and EPSs. The UV-killed cells and EPSs promoted a Th1-type cellular response. Furthermore, we found that the UV-killed cells sent positive signals through Toll-like receptor (TLR) 2. Meanwhile, neither EPS sent a positive signal through TLR4 and TLR2. This evidence suggests that both UV-killed cells of the lactobacillus strains and their EPSs trigger a Th1-type immune response in a human host, with the former triggering the response via the TLRs expressed on its epithelium and the latter employing a mechanism yet to be determined, possibly involving a novel receptor that is designed to recognize specific patterns of repeating sugar in the EPSs.

Changes of Raffinose and Stachyose in Soy Milk Fermentation by Lactic Acid Bacteria From Local Fermented Foods of Indonesian

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Sumarna

2008-01-01

Full Text Available The objective of this study was to evaluate the fermentative characteristics of lactic acid bacteria isolated from local fermented foods and consume raffinose and stachyose during fermentation soymilk. Lactobacillus plantarum pentosus SMN, 01, Lactobacillus casei subsp rhamnosus FNCC, 098, Lactobacillus casei subsp rhamnosus FNCC, 099, Streptococcus thermofilus, 001, Lactobacillus delbrueckii subsp. bulgaricus FNCC, 0045, Lactobacillus plantarum SMN, 25, and Lactobacillus plantarum pentosus FNCC, 235 exhibited variable α-galactosidase activity with Lactobacillus plantarum SMN, 25, showing the highest activity in MRS supplemented media. However, all organisms reached the desired therapeutic level (10^8 cfu/mL likely due to their ability to metabolize oligosaccharides during fermentation in soymilk at 41 °C. The oligosaccharide metabolism depended on α-galactosidase activity. Lactobacillus plantarum SMN, 25, L. plantarum pentosus SMN, 01 and Lactobacillus plantarum pentosus FNCC, 235 reduced raffinose and stachyose by 81.5, 73.0, 67.0 %, and 78.0, 72.5, 66.0 % respectively in soymilk.

Relationships between functional genes in Lactobacillus delbrueckii ssp. bulgaricus isolates and phenotypic characteristics associated with fermentation time and flavor production in yogurt elucidated using multilocus sequence typing.

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Liu, Wenjun; Yu, Jie; Sun, Zhihong; Song, Yuqin; Wang, Xueni; Wang, Hongmei; Wuren, Tuoya; Zha, Musu; Menghe, Bilige; Heping, Zhang

2016-01-01

Lactobacillus delbrueckii ssp. bulgaricus (L. bulgaricus) is well known for its worldwide application in yogurt production. Flavor production and acid producing are considered as the most important characteristics for starter culture screening. To our knowledge this is the first study applying functional gene sequence multilocus sequence typing technology to predict the fermentation and flavor-producing characteristics of yogurt-producing bacteria. In the present study, phenotypic characteristics of 35 L. bulgaricus strains were quantified during the fermentation of milk to yogurt and during its subsequent storage; these included fermentation time, acidification rate, pH, titratable acidity, and flavor characteristics (acetaldehyde concentration). Furthermore, multilocus sequence typing analysis of 7 functional genes associated with fermentation time, acid production, and flavor formation was done to elucidate the phylogeny and genetic evolution of the same L. bulgaricus isolates. The results showed that strains significantly differed in fermentation time, acidification rate, and acetaldehyde production. Combining functional gene sequence analysis with phenotypic characteristics demonstrated that groups of strains established using genotype data were consistent with groups identified based on their phenotypic traits. This study has established an efficient and rapid molecular genotyping method to identify strains with good fermentation traits; this has the potential to replace time-consuming conventional methods based on direct measurement of phenotypic traits. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Proteolytic and antimicrobial activity of lactic acid bacteria grown in goat milk.

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Atanasova, Jivka; Moncheva, Penka; Ivanova, Iskra

2014-11-02

We examined 62 strains and 21 trade starter cultures from the collection of LB Bulgaricum PLC for proteolytic and antimicrobial activity of lactic acid bacteria (LAB) grown in goat milk. The aim of this study was to investigate the fermentation of caseins, α-lactalbumin and β-lactoglobulin by LAB, using the o -phthaldialdehyde (OPA) spectrophotometric assay and sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). The proteolysis targeted mainly caseins, especially β-casein. Whey proteins were proteolyzed, essentially β-lactoglobulin. The proteolytic activity of Lactococcus lactis l598, Streptococcus thermophilus t3D1, Dt1, Lactobacillus lactis 1043 and L. delbrueckii subsp. bulgaricus b38, b122 and b24 was notably high. The proteolysis process gave rise to medium-sized peptide populations. Most of the examined strains showed antimicrobial activity against some food pathogens, such as Escherichia coli , Staphylococcus aureus , Salmonella cholere enteridis , Listeria monocytogenes , Listeria innocua and Enterobacter aerogenes . The most active producers of antimicrobial-active peptides were strains of L. delbrueckii subsp. bulgaricus and S. thermophilus , which are of practical importance. The starter cultures containing the examined species showed high proteolytic and antimicrobial activity in skimmed goat milk. The greatest antimicrobial activity of the cultures was detected against E. aerogenes . The obtained results demonstrated the significant proteolytic potential of the examined strains in goat milk and their potential for application in the production of dairy products from goat's milk. The present results could be considered as the first data on the proteolytic capacity of strains and starter cultures in goat milk for the purposes of trade interest of LB Bulgaricum PLC.

Phenotypic, fermentation characterization, and resistance mechanism analysis of bacteriophage-resistant mutants of Lactobacillus delbrueckii ssp. bulgaricus isolated from traditional Chinese dairy products.

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Deng, Kaibo; Fang, Wei; Zheng, Baodong; Miao, Song; Huo, Guicheng

2018-03-01

Bacteriophage infection is a large factor in dairy industrial production failure on the basis of pure inoculation fermentation, and developing good commercial starter cultures from wild dairy products and improving the environmental vigor of starter cultures by enhancing their phage resistance are still the most effective solutions. Here we used a spontaneous isolation method to obtain bacteriophage-resistant mutants of Lactobacillus delbrueckii ssp. bulgaricus strains that are used in traditional Chinese fermented dairy products. We analyzed their phenotypes, fermentation characteristics, and resistance mechanisms. The results showed that bacteriophage-insensitive mutants (BIM) BIM8 and BIM12 had high bacteriophage resistance while exhibiting fermentation and coagulation attributes that were as satisfying as those of their respective parent strains KLDS1.1016 and KLDS1.1028. According to the attachment receptor detection, mutants BIM8 and BIM12 exhibited reduced absorption to bacteriophage phiLdb compared with their respective bacteriophage-sensitive parent strains because of changes to the polysaccharides or teichoic acids connected to their peptidoglycan layer. Additionally, genes, including HSDR, HSDM, and HSDS, encoding 3 subunits of a type I restriction-modification system were identified in their respective parent strains. We also discovered that HSDR and HSDM were highly conserved but that HSDS was variable because it is responsible for the DNA specificity of the complex. The late lysis that occurred only in strain KLDS1.1016 and not in strain KLDS1.1028 suggests that the former and its mutant BIM8 also may have an activatable restriction-modification mechanism. We conclude that the L. bulgaricus BIM8 and BIM12 mutants have great potential in the dairy industry as starter cultures, and their phage-resistance mechanism was effective mainly due to the adsorption interference and restriction-modification system. Copyright © 2018 American Dairy Science

Impact of Bifidobacterium animalis subsp. lactis BB-12 and, Lactobacillus acidophilus LA-5-containing yoghurt, on fecal bacterial counts of healthy adults.

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Savard, Patricia; Lamarche, Benoît; Paradis, Marie-Eve; Thiboutot, Hélène; Laurin, Émilie; Roy, Denis

2011-09-01

This randomized, placebo-controlled, double blind, parallel dose-response study investigated the impact of 4-week commercial yoghurt consumption supplemented with Bifidobacterium animalis subsp. lactis (BB-12) and Lactobacillus acidophilus (LA-5) on fecal bacterial counts of healthy adults. Fifty-eight volunteers were randomly assigned to three different groups: 1. placebo (no probiotic, no starter and no green tea extract); 2. Yoptimal (10(9)cfu/100g of BB-12 and LA-5 and 40mg of green tea extract) and 3. Yoptimal-10 (10(10)cfu/100g of BB-12, 10(9)cfu/100g of LA-5 and 40mg of green tea extract). These yoghurt products also contained Lactobacillus delbrueckii subsp. bulgaricus (10(7)cfu/100g) and Streptococcus thermophilus (10(10)cfu/100g). The quantitative PCR (qPCR) results showed that there were significant increases (P=0.02) in bifidobacteria counts with the Yoptimal treatment as compared to baseline. The fecal numbers of B. animalis subsp. lactis and LA-5 significantly increased in the two probiotic treatments compared to the placebo treatment. Viable counts of fecal lactobacilli were significantly higher (P=0.05) and those of enterococci were significantly lower (P=0.04) after the intervention when compared to placebo. No significant difference was observed between treatments in volunteers' weight, waist girth, blood pressure, fasting plasma triglyceride and HDL-C concentrations, as well as cholesterol/HDL-cholesterol ratio. However, a significant increase in plasma cholesterol levels was observed in the placebo group (P=0.0018) but the levels remained stable in the two probiotic yoghurt groups. These results show that probiotic strains supplemented in the form of yoghurt remain active during gut transit and are associated with an increase in beneficial bacteria and a reduction in potentially pathogenic bacteria. This trial was registered at clinicaltrials.gov as NCT00730626. Copyright © 2011 Elsevier B.V. All rights reserved.

Evaluación de la producción de ácido láctico a partir de cascarilla de arroz porLactobacillus delbrueckii

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Jeimmy Proaños

2014-06-01

Full Text Available En Colombia se producen más de 2’000.000 de toneladas de arroz y por lo tanto aproximadamente 400.000 toneladas de cascarilla. Este es un subproducto con altos contenidos de polisacáridos que puede ser utilizadopara la producción de azúcares fermentables y su posterior biotransformación en ácido láctico, como alternativa de valorización. En este trabajo se estudióla aplicación de pretratamiento alcalino (NaOH 2 y 3%(m/v, 121 °C, 0,1 MPa, 1h para romper la estructura compleja de la cascarilla y favorecer la producción de ácido láctico mediante un proceso de hidrólisis y fermentación simultáneas (HFS (40 °C, 100 rpm, 48 h.En el proceso de HFS, se estudió la producción de ácido láctico a diferentes concentraciones de cascarilla de arroz (pretratada y sin tratamiento como sustrato(10, 40 y 80 g/L, utilizando enzimas comerciales y Lactobacillus delbrueckii. La máxima concentraciónde ácido láctico obtenida fue de 1,81 ± 0,11 g/L a las 12 h de proceso utilizando cascarilla sin pretratar (80g/L y el máximo rendimiento Y ps fue de 0,075 g de ácido láctico/g de cascarilla, utilizando 20 g/L como sustrato pretratado con NaOH al 3%. Aunque este pretratamiento favorece la producción de ácido láctico a bajas concentraciones de sustrato en el proceso HFS, es necesario explorar otras posibilidades para mejorar los rendimientos obtenidos.

Effect of Pretreatment with Lactobacillus delbrueckii and Streptococcus thermophillus on Tailored Triple Therapy for Helicobacter pylori Eradication: A Prospective Randomized Controlled Clinical Trial.

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Tongtawee, Taweesak; Dechsukhum, Chavaboon; Leeanansaksiri, Wilairat; Kaewpitoon, Soraya; Kaewpitoon, Natthawut; Loyd, Ryan A; Matrakool, Likit; Panpimanmas, Sukij

2015-01-01

Helicobacter pylori plays an important role in gastric cancer and typical eradication regimens are no longer effective in many countries, including Thailand. The aim of our study was to compare the effect of Lactobacillus delbrueckii and Streptococcus thermophillus on tailored triple therapy for Helicobacter pylori eradication. This prospective single-center study was conducted in Thailand. Helicobacter pylori associated gastritis patients were randomized to 2 groups: group 1 (n=100) was tailored triple therapy with placebo (esomeprazole 20 mg bid, clarithromycin 500 mg bid or metronidazole 400 mg tid if clarithromycin resistance and amoxicillin 1000 mg bid), and group 2 was tailored triple therapy plus pretreatment with probiotic containing yogurt. Successful eradication was defined as both negative histology and negative rapid urease test at four weeks after treatment. A total of 200 infected patients were enrolled. PP analysis involved 194 patients: 96 in the tailored triple therapy with placebo group (group 1) and 98 the in tailored triple therapy plus pretreatment with probiotic containing yogurt group (group 2). Successful eradication was observed in 170 (87.6%) patients; by PP analysis, the eradication rate was significantly higher in group 2 (P=0.04, 95%CI; 0.02-0.13) than in group 1. ITT analysis also showed that the value was significantly higher in the tailored triple threapy plus pretreatment with probiotic containing yogurt group (group 2) (89/100; 89%) than in the tailored triple therapy with placebo group (group 1) (P=0.01, 95%CI; 0.04-0.15). In terms of adverse events, there was no significant difference between the two groups. Pretreatment with probiotic containing yogurt can improve Helicobacter pylori eradication rates with tailored triple therapy. Adding probiotics does not reduce adverse effects of the medication.

DETERMINATION OF QUALITY PROPERTIES OF DIET ACIDOPHILUS BIFIDUS YOGHURT AND DIET YOGHURT

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Oğuz GÜRSOY

1999-03-01

Full Text Available Diet yoghurt and diet Asidophilus bifidus yoghurt were produced from cow milk and fat ratio was decreased below 1 %. In production of diet Asidophilus bifidus yoghurt, freeze dried DVS culture which contains normal yoghurt bacteria (Streptococcus thermophilus ve Lactobacillus delbrueckii subsp. bulgaricus and therapeutic lactic acid bacteria (Lactobacillus acidophilus and Bifidobacteria was used. In production of diet yoghurt, normal yoghurt bacteria were used. Chemical, microbiological and sensory properties of these products were determined and compared. Generally, except the consistency sensed in mouth, chemical, microbiological and sensory properties were approximately same. Finally, these products were healthier than other yoghurt products, because of the amount of low fat and containing therapeutic bacteria.

Unprecedented large inverted repeats at the replication terminus of circular bacterial chromosomes suggest a novel mode of chromosome rescue

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El Kafsi, Hela; Loux, Valentin; Mariadassou, Mahendra; Blin, Camille; Chiapello, Hélène; Abraham, Anne-Laure; Maguin, Emmanuelle; van de Guchte, Maarten

2017-01-01

The first Lactobacillus delbrueckii ssp. bulgaricus genome sequence revealed the presence of a very large inverted repeat (IR), a DNA sequence arrangement which thus far seemed inconceivable in a non-manipulated circular bacterial chromosome, at the replication terminus. This intriguing observation prompted us to investigate if similar IRs could be found in other bacteria. IRs with sizes varying from 38 to 76 kbp were found at the replication terminus of all 5 L. delbrueckii ssp. bulgaricus chromosomes analysed, but in none of 1373 other chromosomes. They represent the first naturally occurring very large IRs detected in circular bacterial genomes. A comparison of the L. bulgaricus replication terminus regions and the corresponding regions without IR in 5 L. delbrueckii ssp. lactis genomes leads us to propose a model for the formation and evolution of the IRs. The DNA sequence data are consistent with a novel model of chromosome rescue after premature replication termination or irreversible chromosome damage near the replication terminus, involving mechanisms analogous to those proposed in the formation of very large IRs in human cancer cells. We postulate that the L. delbrueckii ssp. bulgaricus-specific IRs in different strains derive from a single ancestral IR of at least 93 kbp. PMID:28281695

Microbiological and chemical characteristics of tarubá, an indigenous beverage produced from solid cassava fermentation.

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Ramos, Cíntia L; de Sousa, Edinaira S O; Ribeiro, Jessimara; Almeida, Tayanny M M; Santos, Claudia Cristina A do A; Abegg, Maxwel A; Schwan, Rosane F

2015-08-01

The aim of this work was to identify and characterize the microbiota present during fermentation and in the final beverage, tarubá, by culture-dependent and -independent methods. In addition, target chemical compounds (carbohydrates, organic acids, and ethanol) were evaluated. Lactic acid bacteria (LAB) and mesophilic bacteria were the predominant microorganisms. Among them, Lactobacillus plantarum, Lactobacillus brevis, Leuconostoc mesenteroides, and Bacillus subtilis were frequently isolated and detected by DGGE analysis. Torulaspora delbrueckii was the dominant yeast species. Yeast isolates Pichia exigua, Candida rugosa, T. delbrueckii, Candida tropicalis, Pichia kudriavzevii, Wickerhamomyces anomalus, and Candida ethanolica and bacteria isolates Lb. plantarum, Bacillus subtilis, Bacillus amyloliquefaciens, Bacillus licheniformis, Bacillus sp., and Chitinophaga terrae showed amylolytic activity. Only isolates of P. exigua and T. delbrueckii and all species of the genus Bacillus identified in this work exhibited proteolytic activity. All microbial isolates grew at 38 °C, and only the isolates belonging to Hanseniaspora uvarum species did not grow at 42 °C. These characteristics are important for further development of starter cultures; isolates of T. delbrueckii, P. exigua, and Bacillus species identified in this work displayed all of these properties and are potential strains for use as starter culture in cassava fermented food. Copyright © 2015 Elsevier Ltd. All rights reserved.

Identificação bioquímica e molecular de Lactobacillus spp. isolados do íleo de frangos de corte tratados ou não com antimicrobianos Biochemical and molecular characterization of Lactobacillus spp. isolated from the ileum of broilers treated with or without antimicrobials

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Surama Freitas Zanini

2012-09-01

Full Text Available Objetivou-se caracterizar bioquimicamente e molecularmente as espécies de Lactobacillus spp. isoladas do íleo de frangos de corte tratados ou não com antimicrobianos. Utilizou-se 400 pintos de corte alojados em 25 boxes de 2m² (16 aves/boxe, distribuídos em um delineamento inteiramente casualizado, em grupos de cinco tratamentos e cinco repetições: dieta sem promotor de crescimento; dieta com promotor de crescimento; dieta com 0,4% de óleo de aroeira-vermelha (OAV; dieta com 200mg de vitamina E kg-1; dieta com 0,4% OAV e 200mg de vitamina E kg-1. Após a caracterização fenotípica do gênero Lactobacillus, foram identificadas, em ambas as metodologias, 100 amostras de Lactobacillus spp. sendo 20 amostras por tratamento. Os resultados bioquímicos identificaram L. acidophilus, L. fermentum, L. plantarum, L. delbrueckii subsp. delbrueckii além de Lactococcus lactis subp. lactis. Para as amostras padrão ATCC, a identificação bioquímica suscitou algumas dúvidas em relação aos seus resultados. Os resultados da identificação molecular mostraram que os Lactobacillus que amplificaram ambos os iniciadores (LU-1'/ Lac-2 e (Laci-1 / 23-10C são os da espécie L. acidophilus. As amostras que amplificaram apenas com o iniciador (LU-1'/ Lac-2 tratam-se das demais espécies que compõe o grupo L. acidophilus. Já as amostras com o iniciador L. fermentum (Fer 3/Fer 4 amplificaram um fragmento de 192pb padrão para essa espécie. Conclui-se que a identificação das espécies de Lactobacillus spp. isoladas do íleo a partir da PCR apresentou-se mais sensível que o método bioquímico.This study aimed to characterize biochemically and molecular species of Lactobacillus spp. isolated from the ileum of broiler chickens treated with or without antimicrobial. A total of 400 day-old male chicks, Cobb, distributed in a randomized design in groups of five treatments and five replicates: diet without antimicrobials; diet with antimicrobials; diet

The influences of fish infusion broth on the biogenic amines formation by lactic acid bacteria

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Esmeray Küley

2013-01-01

Full Text Available The influences of fish infusion decarboxylase broth (IDB on biogenic amines (BA formation by lactic acid bacteria (LAB were investigated. BA productions by single LAB strains were tested in five different fish (anchovy, mackerel, white shark, sardine and gilthead seabream IDB. The result of the study showed that significant differences in ammonia (AMN and BA production were observed among the LAB strains in fish IDB (p < 0.05. The highest AMN and TMA production by LAB strains were observed for white shark IDB. The all tested bacteria had decarboxylation activity in fish IDB. The uppermost accumulated amines by LAB strains were tyramine (TYM, dopamine, serotonin and spermidine. The maximum histamine production was observed in sardine (101.69 mg/L and mackerel (100.84 mg/L IDB by Leuconostoc mesenteroides subsp. cremoris and Pediococcus acidophilus, respectively. Lactobacillus delbrueckii subsp. lactis and Pediococcus acidophilus had a high TYM producing capability (2943 mg/L and 1157 mg/L in sardine IDB.

Bioaugmentation of Lactobacillus delbrueckii ssp. bulgaricus TISTR 895 to enhance bio-hydrogen production of Rhodobacter sphaeroides KKU-PS5.

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Laocharoen, Sucheera; Reungsang, Alissara; Plangklang, Pensri

2015-01-01

Bioaugmentation or an addition of the desired microorganisms or specialized microbial strains into the anaerobic digesters can enhance the performance of microbial community in the hydrogen production process. Most of the studies focused on a bioaugmentation of native microorganisms capable of producing hydrogen with the dark-fermentative hydrogen producers while information on bioaugmentation of purple non-sulfur photosynthetic bacteria (PNSB) with lactic acid-producing bacteria (LAB) is still limited. In our study, bioaugmentation of Rhodobacter sphaeroides KKU-PS5 with Lactobacillus delbrueckii ssp. bulgaricus TISTR 895 was conducted as a method to produce hydrogen. Unfortunately, even though well-characterized microorganisms were used in the fermentation system, a cultivation of two different organisms in the same bioreactor was still difficult because of the differences in their metabolic types, optimal conditions, and nutritional requirements. Therefore, evaluation of the physical and chemical factors affecting hydrogen production of PNSB augmented with LAB was conducted using a full factorial design followed by response surface methodology (RSM) with central composite design (CCD). A suitable LAB/PNSB ratio and initial cell concentration were found to be 1/12 (w/w) and 0.15 g/L, respectively. The optimal initial pH, light intensity, and Mo concentration obtained from RSM with CCD were 7.92, 8.37 klux and 0.44 mg/L, respectively. Under these optimal conditions, a cumulative hydrogen production of 3396 ± 66 mL H2/L, a hydrogen production rate (HPR) of 9.1 ± 0.2 mL H2/L h, and a hydrogen yield (HY) of 9.65 ± 0.23 mol H2/mol glucose were obtained. KKU-PS5 augmented with TISTR 895 produced hydrogen from glucose at a relatively high HY, 9.65 ± 0.23 mol H2/mol glucose, i.e., 80 % of the theoretical yield. The ratio of the strains TISTR 895/KKU-PS5 and their initial cell concentrations affected the rate of lactic acid production and its

Oral administration of Lactobacillus delbrueckii subspecies bulgaricus OLL1073R-1 suppresses inflammation by decreasing interleukin-6 responses in a murine model of atopic dermatitis.

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Kano, Hiroshi; Kita, Junko; Makino, Seiya; Ikegami, Shuji; Itoh, Hiroyuki

2013-06-01

The oral intake of Lactobacillus spp. can provide beneficial effects to the host by modulating the immune response. Atopic dermatitis (AD) is an allergic inflammatory disease mediated by various immune responses. In this study, we examined the effect of a Lactobacillus strain, Lactobacillus delbrueckii ssp. bulgaricus OLL1073R-1 (OLL1073R-1), on AD development in a murine model of AD that was developed by the topical application of mite antigen in NC/Nga mice. The oral intake of heat-killed OLL1073R-1 cells inhibited both the development of dermatitis and the elevation of an acute inflammation marker, serum amyloid A. Another bacterial strain, Lactobacillus rhamnosus OLL2984, exerted no inhibitory effects on dermatitis. The oral intake of heat-killed OLL1073R-1 cells also attenuated secretion of IL-6 from lymph node cells in response to mite antigen and reduced IL-6 levels in inflamed tissues, such as auricles. Production of IFN-γ or IL-4 was not influenced by OLL1073R-1 intake. We also found that inhibition of IL-6 signaling by gp130-Fc (a fusion protein consisting of the extracellular portion of glycoprotein 130 fused to the Fc region of human IgG1) markedly decreased the severity of dermatitis in NC/Nga mice. Moreover, secretion of IL-6 by lymph node cells was augmented in NC/Nga mice compared with that in BALB/c mice. These results indicate that IL-6 plays an essential role in the development of dermatitis in the NC/Nga mouse model of AD, and that OLL1073R-1 inhibits dermatitis, at least in part, by suppressing the IL-6 response. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Dynamic analysis of Lactobacillus delbrueckii subsp. bulgaricus CFL1 physiological characteristics during fermentation.

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Rault, Aline; Bouix, Marielle; Béal, Catherine

2008-12-01

This study aimed at examining and comparing the relevance of various methods in order to discriminate different cellular states of Lactobacillus bulgaricus CFL1 and to improve knowledge on the dynamics of the cellular physiological state during growth and acidification. By using four fluorescent probes combined with multiparametric flow cytometry, membrane integrity, intracellular esterase activity, cellular vitality, membrane depolarization, and intracellular pH were quantified throughout fermentations. Results were compared and correlated with measurements of cultivability, acidification activity (Cinac system), and cellular ability to recover growth in fresh medium (Bioscreen system). The Cinac system and flow cytometry were relevant to distinguish different physiological states throughout growth. Lb. bulgaricus cells maintained their high viability, energetic state, membrane potential, and pH gradient in the late stationary phase, despite the gradual decrease of both cultivability and acidification activity. Viability and membrane integrity were maintained during acidification, at the expense of their cultivability and acidification activity. Finally, this study demonstrated that the physiological state during fermentation was strongly affected by intracellular pH and the pH gradient. The critical pHi of Lb. bulgaricus CFL1 was found to be equal to pH 5.8. Through linear relationships between dpH and cultivability and pHi and acidification activity, pHi and dpH well described the time course of metabolic activity, cultivability, and viability in a single analysis.

Lactic Acid and Probiotic Bacteria from Fermented and Probiotic Dairy Products

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B.K.L. Karna

2007-12-01

Full Text Available Lactic acid and probiotic bacteria were enumerated and isolated from commercially available yoghurt andprobiotic milk products. Lactobacillus delbrueckii ssp. bulgaricus were enumerated and isolated usingMRS agar incubated anaerobically at 37oC for 72 hrs. M17 agar was used for the enumeration andisolation of Streptococcus thermophilus incubated aerobically at 37oC for 48 hrs. MRS agar and modifiedMRS agar (MRS + L-cysteine + LiCl + Na propionate were used for the enumeration and isolation ofprobiotic bacteria. Both were incubated anaerobically at 37oC for 72 hrs. Morphological, physiologicaland biochemical reactions were used to characterize the isolates.Str. thermophilus counts ranged from 2.6 x 1011 to 2.9 x 1020 CFU/g with Fruit Yoghurt (FY having thehighest count and Yoghurt Natural (YN with the lowest count. Highest Lactobacillus delbrueckii ssp.bulgaricus count was obtained in Duo Yoghurt (DY, 1.1 x 109 and lowest in Yoghurt Drink (YD, 8.0 x 107CFU/g. The highest probiotic bacterial count of 2.3 x 108 was obtained in Yakult (YK and Neslac (Nesshowed the lowest, 1.6 x 102 CFU/g. The viable counts of all the products examined met the prescribedminimum viable count of 105 to 106CFU/g for the claimed health benefits for the consumer except forChamyto Plain (CP, Nes and Nan-2 (Nan.Morphological, physiological and biochemical characteristics showed that the following genera andspecies were present Pediococcus acidilactici (YN, P. pentosaceus (FY, Lactobacillus delbrueckiidelbrueckii and L. brevis in Non Fat High Calcium Yoghurt (NC, L. acidophilus and L. delbrueckiidelbrueckii (DY, YD, P. damnosus and P. pentosaceus in Chamyto Orange (CO, L. delbrueckii bulgaricus,L. acidophilus, and L. delbrueckii delbrueckii (CP, L. para. paracasei (YK and Bifidobacterium ssp.(Nes and Nan.Of the 28 isolates characterized in this study, 15 were Lactobacillus (5 species, 5 werePediococcus (3 species, 6 were Bifidobacterium (species not identified, and 2 were

An operon from Lactobacillus helveticus composed of a proline iminopeptidase gene (pepI) and two genes coding for putative members of the ABC transporter family of proteins.

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Varmanen, P; Rantanen, T; Palva, A

1996-12-01

A proline iminopeptidase gene (pepI) of an industrial Lactobacillus helveticus strain was cloned and found to be organized in an operon-like structure of three open reading frames (ORF1, ORF2 and ORF3). ORF1 was preceded by a typical prokaryotic promoter region, and a putative transcription terminator was found downstream of ORF3, identified as the pepI gene. Using primer-extension analyses, only one transcription start site, upstream of ORF1, was identifiable in the predicted operon. Although the size of mRNA could not be judged by Northern analysis either with ORF1-, ORF2- or pepI-specific probes, reverse transcription-PCR analyses further supported the operon structure of the three genes. ORF1, ORF2 and ORF3 had coding capacities for 50.7, 24.5 and 33.8 kDa proteins, respectively. The ORF3-encoded PepI protein showed 65% identity with the PepI proteins from Lactobacillus delbrueckii subsp. bulgaricus and Lactobacillus delbrueckii subsp. lactis. The ORF1-encoded protein had significant homology with several members of the ABC transporter family but, with two distinct putative ATP-binding sites, it would represent an unusual type among the bacterial ABC transporters. ORF2 encoded a putative integral membrane protein also characteristic of the ABC transporter family. The pepI gene was overexpressed in Escherichia coli. Purified PepI hydrolysed only di and tripeptides with proline in the first position. Optimum PepI activity was observed at pH 7.5 and 40 degrees C. A gel filtration analysis indicated that PepI is a dimer of M(r) 53,000. PepI was shown to be a metal-independent serine peptidase having thiol groups at or near the active site. Kinetic studies with proline-p-nitroanilide as substrate revealed Km and Vmax values of 0.8 mM and 350 mmol min-1 mg-1, respectively, and a very high turnover number of 135,000 s-1.

Protective role of probiotic lactic acid bacteria against dietary fumonisin B1-induced toxicity and DNA-fragmentation in sprague-dawley rats.

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Khalil, Ashraf A; Abou-Gabal, Ashgan E; Abdellatef, Amira A; Khalid, Ahmed E

2015-08-18

The genus Fusarium, especially F. verticillioides and F. proliferatum, has been found in several agricultural products worldwide, especially in maize. Regardless the occurrence of symptoms, the presence of Fusarium in maize constitutes an imminent risk due to its ability to produce fumonisins, mycotoxins with proven carcinogenic effect on rats, swine, and equines and already classified as possible carcinogens to humans. The toxicity of incremental levels of fumonisin B1 (FB1), that is, 50, 100, and 200 mg FB1/kg diet, and the role of Lactobacillus delbrueckii subsp. lactis DSM 20076 (LL) and Pediococcus acidilactici NNRL B-5627 (PA) supplementation in counteracting the FB1 effects in intoxicated rats were monitored over a period of 4 weeks. Effects on the feed intake and body weight gain were noticed. A significant (p ≤ 0.05) increase in the level of liver and kidney functions markers and DNA fragmentation was also noticed in rat groups T100 and T200. The lactic acid bacteria (LAB) supplementation could bring back the normal serum biochemical parameters in rats fed on fumonisin B1-contaminated diets (T50 and T100) compared to FB1-treated groups. In rats of high-dosage dietary groups supplemented with LAB (T200-LL and T200-PA), the supplementation reduced the serum activity levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), and creatinine by 11.3, 11.9, 32, and 20%, respectively. DNA fragmentations were observed in the rat group treated with 200 mg FB1 after 3 weeks, while fragmentation was noticed in treated groups with 100 and 200 mg FB1 after 4 weeks. No DNA fragmentation was apparent in FB1-treated rats co-administered the LL or PA strain. These results suggest that in male rats consuming diets containing FB1, there is a time- and dose-dependent increase in serum enzyme activities and DNA lesions. Moreover, Lb. delbrueckii subsp. lactis (LL) and P. acidilactici (PA) strains have a protective effect

Lactobacillus bulgaricus Fajlarının Restriksiyon Fragment Uzunluk Polimorfizmi, Protein Profilleri ve Konakçı Özgüllüklerine Göre Tanımlanması

OpenAIRE

Soykut, Esra Acar; Tunail, Nezihe

2014-01-01

Lactobacillus delbrueckii subsp. bulgaricus suşlarına etkili 19 adet faj, restriksiyon fragment uzunluk polimorfizmi (RFLP), yapısal protein şablonları ve konakçı spektrumlarına göre tanımlanmış ve sınıflandırılmıştır. Fajlar, farklı süt ürünlerinden L. bulgaricus starter kültürleri (Y4, V1 ve V2) ile izole edilmiştir. Konakçı spektrumunun belirlenmesi için; doğal ve ticari L. bulgaricus suşlarının L. bulgaricus V1 ve V2 fajları ile S. thermophilus B3 fajlarına duyarlılıkları test edilmiştir....

Identification and Functional Validation of Autolysis-Associated Genes in Lactobacillus bulgaricus ATCC BAA-365.

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Pang, Xiaoyang; Zhang, Shuwen; Lu, Jing; Liu, Lu; Ma, Changlu; Yang, Yang; Ti, Panpan; Gao, Weihua; Lv, Jiaping

2017-01-01

Lactic acid bacteria (LAB) are important organisms in food production. Indeed, LAB autolysis is very critical in dairy processing. For example, it influences the development of cheese flavor by releasing intracellular enzymes, and controls cell growth in yogurts and probiotic products. Two component systems (TCS) constitute essential environmental sensors and effectors of signal transduction in most bacteria. In the present work, mutants of one TCS (LBUL_RS00115/LBUL_RS00110) were generated to assess the relationship between TCS and cell autolysis. The mutants displayed decreased autolysis in comparison with wild type; meanwhile, complementation reversed this effect. The interaction between LBUL_RS00115 and LBUL_RS00110 was confirmed by yeast two-hybrid analysis. These observations suggested that the TCS (LBUL_RS00115/LBUL_RS00110) was involved in autolysis in Lactobacillus delbrueckii subsp. bulgaricus .

Effect of probiotics on the development of dimethylhydrazine-induced preneoplastic lesions in the mice colon

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Juliana Costa Liboredo

2013-05-01

Full Text Available PURPOSE: To determine the effect of probiotics on the development of chemically induced (1, 2-dimethylhydrazine colonic preneoplastic lesions, in mice. METHODS: The animals were divided into five groups. The control group was injected with carcinogen alone and the other groups also received probiotics (1- Lactobacillus delbrueckii UFV-H2b20; 2- Bifidobacterium animalis var. lactis Bb12; 3- L. delbrueckii UFV-H2b20 plus B. animalis var. lactis Bb12; and 4- Saccharomyces boulardii administered orally in drinking water throughout fourteen weeks. RESULTS: Consumption of lactobacilli and bifidobacteria alone resulted in a significant reduction of the total number of aberrant crypt foci (55.7% and 45.1%, respectively. Significant reduction in the number of these small foci (3 aberrant crypts crypts had no significant reduction. CONCLUSION: L. delbrueckii UFV-H2b20 and B. animalis var. lactis Bb12 administered alone protect colonic preneoplastic lesions in mice, while the combined treatment of these bacteria and the administration of S.boulardii were not effective in reducing such colonic lesions.

Reactive oxygen species and lipid peroxidation product-scavenging ability of yogurt organisms.

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Lin, M Y; Yen, C L

1999-08-01

The antioxidative activity of the intracellular extracts of yogurt organisms was investigated. All 11 strains tested, including five strains of Streptococcus thermophilus and six strains of Lactobacillus delbrueckii ssp. bulgaricus, demonstrated an antioxidative effect on the inhibition of linoleic acid peroxidation. The antioxidative effect of intracellular extracts of 10(8) cells of yogurt organisms was equivalent to 25 to 96 ppm butylated hydroxytoluene, which indicated that all strains demonstrated excellent antioxidative activity. The scavenging of reactive oxygen species, hydroxyl radical, and hydrogen peroxide was studied for intracellular extracts of yogurt organisms. All strains showed reactive oxygen species-scavenging ability. Lactobacillus delbrueckii ssp. bulgaricus Lb demonstrated the highest hydroxyl radical-scavenging ability at 234 microM. Streptococcus thermophilus MC and 821 and L. delbrueckii ssp. bulgaricus 448 and 449 scavenged the most hydrogen peroxide at approximately 50 microM. The scavenging ability of lipid peroxidation products, t-butylhydroperoxide and malondialdehyde, was also evaluated. Results showed that the extracts were not able to scavenge the t-butylhydroperoxide. Nevertheless, malondialdehyde was scavenged well by most strains.

Fig Juice Fermented with Lactic Acid Bacteria as a Nutraceutical Product

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Sima Khezri 1, Parvin Dehghan 2 * , Razzagh Mahmoudi 3, Mahdi Jafarlou 4

2016-12-01

Full Text Available Background: Probiotics are live microorganisms bringing useful effects to the host through balancing intestine microbiota. This research was undertaken to determine the suitability of fig juice as raw material for production of probiotic juice by three species of lactic acid bacteria (Lactobacillus casei, Lactobacillus plantarum and Lactobacillus delbrueckii. Methods: Heat treated fig juices were inoculated (6 log CFU/ml by three species inocula separately and incubated at 30 °C for 72 h. Changes in the pH, acidity, reducing sugar content and viable cell counts during the fermentation were monitored. Sensory characteristics of probiotic fig juice were also evaluated. Results: L. delbrueckii grew well on fig juice; reached nearly 9 log CFU/ml after 48 h of fermentation at 30 °C. After 4 weeks of cold storage at 4 °C, the viable cell counts of L. delbrueckii and L. plantarum were still 6 and 5 log CFU/ml, respectively, in fermented fig juice; but L. casei was just survived until 2th week of cold storage time, reduced from 9 to 3 log CFU/ml. The results of the sensory evaluation showed that fermented fig juice samples were significantly different (P<0.05 from the control sample in taste, odor, consistency and overall acceptability. L. casei was more acceptable comparing to the others. Conclusion: L. delbrueckii was the most suitable strain from the point of survivability among other species at the consumption time. Therefore, probiotic fig juice can serve as healthy beverage for vegetarians and consumers with lactose-allergy.

Manufacture of Fior di Latte cheese by incorporation of probiotic lactobacilli.

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Minervini, F; Siragusa, S; Faccia, M; Dal Bello, F; Gobbetti, M; De Angelis, M

2012-02-01

This work aimed to select heat-resistant probiotic lactobacilli to be added to Fior di Latte (high-moisture cow milk Mozzarella) cheese. First, 18 probiotic strains belonging to Lactobacillus casei, Lactobacillus delbrueckii ssp. bulgaricus, Lactobacillus paracasei, Lactobacillus plantarum, Lactobacillus rhamnosus, and Lactobacillus reuteri were screened. Resistance to heating (65 or 55°C for 10 min) varied markedly between strains. Adaptation at 42°C for 10 min increased the heat resistance at 55°C for 10 min of all probiotic lactobacilli. Heat-adapted L. delbrueckii ssp. bulgaricus SP5 (decimal reduction time at 55°C of 227.4 min) and L. paracasei BGP1 (decimal reduction time at 55°C of 40.8 min) showed the highest survival under heat conditions that mimicked the stretching of the curd and were used for the manufacture of Fior di Latte cheese. Two technology options were chosen: chemical (addition of lactic acid to milk) or biological (Streptococcus thermophilus as starter culture) acidification with or without addition of probiotics. As determined by random amplified polymorphic DNA-PCR and 16S rRNA gene analyses, the cell density of L. delbrueckii ssp. bulgaricus SP5 and L. paracasei BGP1 in chemically or biologically acidified Fior di Latte cheese was approximately 8.0 log(10)cfu/g. Microbiological, compositional, biochemical, and sensory analyses (panel test by 30 untrained judges) showed that the use of L. delbrueckii ssp. bulgaricus SP5 and L. paracasei BGP1 enhanced flavor formation and shelf-life of Fior di Latte cheeses. Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

[Isolation and characterization of vaginal lactobacilli producing hydrogen peroxide].

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Pashaian, M M; Oganesian, G G

2011-01-01

Isolation and characteristics of vaginal lactobacilli that actively generate H2O2 and have high antagonistic activity. Staphylococcus aureus 8956, Escherichia coli 8852, Klebsiella pneumoniae 8795 and Candida albicans 5646 were used as target-strains. Skim milk and MRS medium were used for lactobacilli isolation and cultivation. Antagonism was studied in complete agar and Saburo medium. Merckoquant peroxide test (Merck) stripes were used for the determination of H2O2. Antibacterial activity was determined by diffusion into agar. Specific culture growth rate was determined by conventional method, acidification of the culture medium--by pH-meter. 12 strains were isolated from vaginal smears of healthy women. These strains have an ability to ferment milk among which a highly active H2O2 producer was isolated and attributed to Lactobacillus delbrueckii by the results of 16S rRNA and alpha-subunit RNA polymerase gene sequence analysis (16S rDNA and rpoA genes are registered in GenBank, numbers HQ379171 and HQ379180 respectively). L. delbrueckii MH-10 bacterial cells were characterized by specific growth speed 1.26 per hour, reaching a maximum titer of 2 x 10(9) PFU/ml with lowering medium pH to 4.0. Under aerated conditions H2O2 concentration reached 100 microg/ml or more. L. delbrueckii MH-10 has high antibacterial activity against S. aureus, E. coli, K. pneumoniae. L. delbrueckii MH-10 isolate is an active H2O2 producer, has high growth speed and broad antibacterial activity spectrum, is a perspective candidate for the development of probiotic preparation for the prophylaxis and therapy of vaginoses.

Identification and Functional Validation of Autolysis—Associated Genes in Lactobacillus bulgaricus ATCC BAA-365

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Xiaoyang Pang

2017-07-01

Full Text Available Lactic acid bacteria (LAB are important organisms in food production. Indeed, LAB autolysis is very critical in dairy processing. For example, it influences the development of cheese flavor by releasing intracellular enzymes, and controls cell growth in yogurts and probiotic products. Two component systems (TCS constitute essential environmental sensors and effectors of signal transduction in most bacteria. In the present work, mutants of one TCS (LBUL_RS00115/LBUL_RS00110 were generated to assess the relationship between TCS and cell autolysis. The mutants displayed decreased autolysis in comparison with wild type; meanwhile, complementation reversed this effect. The interaction between LBUL_RS00115 and LBUL_RS00110 was confirmed by yeast two-hybrid analysis. These observations suggested that the TCS (LBUL_RS00115/LBUL_RS00110 was involved in autolysis in Lactobacillus delbrueckii subsp. bulgaricus.

Identification and Functional Validation of Autolysis—Associated Genes in Lactobacillus bulgaricus ATCC BAA-365

Science.gov (United States)

Pang, Xiaoyang; Zhang, Shuwen; Lu, Jing; Liu, Lu; Ma, Changlu; Yang, Yang; Ti, Panpan; Gao, Weihua; Lv, Jiaping

2017-01-01

Lactic acid bacteria (LAB) are important organisms in food production. Indeed, LAB autolysis is very critical in dairy processing. For example, it influences the development of cheese flavor by releasing intracellular enzymes, and controls cell growth in yogurts and probiotic products. Two component systems (TCS) constitute essential environmental sensors and effectors of signal transduction in most bacteria. In the present work, mutants of one TCS (LBUL_RS00115/LBUL_RS00110) were generated to assess the relationship between TCS and cell autolysis. The mutants displayed decreased autolysis in comparison with wild type; meanwhile, complementation reversed this effect. The interaction between LBUL_RS00115 and LBUL_RS00110 was confirmed by yeast two-hybrid analysis. These observations suggested that the TCS (LBUL_RS00115/LBUL_RS00110) was involved in autolysis in Lactobacillus delbrueckii subsp. bulgaricus. PMID:28769917

Synthesis of β-Maltooligosaccharides of Glycitein and Daidzein and their Anti-Oxidant and Anti-Allergic Activities

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Hiroki Hamada

2010-07-01

Full Text Available The production of β-maltooligosaccharides of glycitein and daidzein using Lactobacillus delbrueckii and cyclodextrin glucanotransferase (CGTase as biocatalysts was investigated. The cells of L. delbrueckii glucosylated glycitein and daidzein to give their corresponding 4'- and 7-O-β-glucosides. The β-glucosides of glycitein and daidzein were converted into the corresponding  β-maltooligosides by CGTase. The 7-O-β-glucosides of glycitein and daidzein and 7-O-β-maltoside of glycitein showed inhibitory effects on IgE antibody production. On the other hand, β-glucosides of glycitein and daidzein exerted 2,2-diphenyl-1-picrylhydrazyl (DPPH free-radical scavenging activity and supeoxide-radical scavenging activity.

Variability of bacterial biofilms of the "tina" wood vats used in the ragusano cheese-making process.

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Licitra, G; Ogier, J C; Parayre, S; Pediliggieri, C; Carnemolla, T M; Falentin, H; Madec, M N; Carpino, S; Lortal, S

2007-11-01

Ragusano cheese is a "protected denomination of origin" cheese made in the Hyblean region of Sicily from raw milk using traditional wooden tools, without starter. To explore the Ragusano bacterial ecosystem, molecular fingerprinting was conducted at different times during the ripening and biofilms from the wooden vats called "tinas" were investigated. Raw milks collected at two farm sites, one on the mountain and one at sea level, were processed to produce Ragusano cheese. Raw milk, curd before and after cooking, curd at stretching time (cheese 0 time), and cheese samples (4 and 7 months) were analyzed by PCR-temporal temperature gel electrophoresis (PCR-TTGE) and by classical enumeration microbiology. With the use of universal primers, PCR-TTGE revealed many differences between the raw milk profiles, but also notable common bands identified as Streptococcus thermophilus, Lactobacillus lactis, Lactobacillus delbrueckii, and Enterococcus faecium. After the stretching, TTGE profiles revealed three to five dominant species only through the entire process of ripening. In the biofilms of the two tinas used, one to five species were detected, S. thermophilus being predominant in both. Biofilms from five other tinas were also analyzed by PCR-TTGE, PCR-denaturating gradient gel electrophoresis, specific PCR tests, and sequencing, confirming the predominance of lactic acid bacteria (S. thermophilus, L. lactis, and L. delbrueckii subsp. lactis) and the presence of a few high-GC-content species, like coryneform bacteria. The spontaneous acidification of raw milks before and after contact with the five tinas was followed in two independent experiments. The lag period before acidification can be up to 5 h, depending on the raw milk and the specific tina, highlighting the complexity of this natural inoculation system.

Impact of thistle rennet from Carlina acanthifolia All. subsp. acanthifolia on bacterial diversity and dynamics of a specialty Italian raw ewes' milk cheese.

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Cardinali, Federica; Osimani, Andrea; Taccari, Manuela; Milanović, Vesna; Garofalo, Cristiana; Clementi, Francesca; Polverigiani, Serena; Zitti, Silvia; Raffaelli, Nadia; Mozzon, Massimo; Foligni, Roberta; Franciosi, Elena; Tuohy, Kieran; Aquilanti, Lucia

2017-08-16

Caciofiore della Sibilla is an Italian specialty soft cheese manufactured with Sopravissana raw ewes' milk and thistle rennet prepared with young fresh leaves and stems of Carlina acanthifolia All. subsp. acanthifolia, according to an ancient tradition deeply rooted in the territory of origin (mountainous hinterland of the Marche region, Central Italy). In this study, the impact of thistle rennet on the bacterial dynamics and diversity of Caciofiore della Sibilla cheese was investigated by applying a polyphasic approach based on culture and DNA-based techniques (Illumina sequencing and PCR-DGGE). A control cheese manufactured with the same batch of ewes' raw milk and commercial animal rennet was analyzed in parallel. Overall, a large number of bacterial taxa were identified, including spoilage, environmental and pro-technological bacteria, primarily ascribed to Lactobacillales. Thistle rennet was observed clearly to affect the early bacterial dynamics of Caciofiore della Sibilla cheese with Lactobacillus alimentarius/paralimentarius and Lactobacillus plantarum/paraplantarum/pentosus being detected in the phyllosphere of C. acanthifolia All., thistle rennet and curd obtained with thistle rennet. Other bacterial taxa, hypothetically originating from the vegetable coagulant (Enterococcus faecium, Lactobacillus brevis, Lactobacillus delbrueckii, Leuconostoc mesenteroides/pseudomesenteroides), were exclusively found in Caciofiore della Sibilla cheese by PCR-DGGE. At the end of the maturation period, Illumina sequencing demonstrated that both cheeses were dominated by Lactobacillales; however curd and cheese produced with thistle rennet were co-dominated by Lactobacillus and Leuconostoc, whereas Lactoccous prevailed in curd and cheese produced with commercial animal rennet followed by Lactobacillus. Differences in the bacterial composition between the two cheeses at the end of their maturation period were confirmed by PCR-DGGE analysis. Copyright © 2017 Elsevier B

Identification of Lactobacillus UFV H2b20 (probiotic strain using DNA-DNA hybridization Identificação de Lactobacillus UFV H2b20 (linhagem probiótica através de hibridização DNA-DNA

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J.T. de Magalhães

2008-09-01

Full Text Available Sequence analyses of the 16S rDNA gene and DNA-DNA hybridization tests were performed for identification of the species of the probiotic Lactobacillus UFV H2b20 strain. Using these two tests, we concluded that this strain, originally considered Lact. acidophilus, should be classified as Lact. delbrueckii.Análise da seqüência do gene 16S rDNA e ensaios de hibridização DNA_DNA foram empregados para identificar a espécie da cepa probiótica Lactobacillus UFV H2b20. Empregando-se estes dois testes, concluímos que esta cepa, originalmente considerada Lact. acidophilus, deve ser classificada como Lact. delbrueckii.

Effects of NS lactobacillus strains on lipid metabolism of rats fed a high-cholesterol diet

Science.gov (United States)

2013-01-01

Background Elevated serum cholesterol level is generally considered to be a risk factor for the development of cardiovascular diseases which seriously threaten human health. The cholesterol-lowering effects of lactic acid bacteria have recently become an area of great interest and controversy for many researchers. In this study, we investigated the effects of two NS lactobacillus strains, Lactobacillus plantarum NS5 and Lactobacillus delbrueckii subsp. bulgaricus NS12, on lipid metabolism of rats fed a high cholesterol diet. Methods Thirty-two SD rats were assigned to four groups and fed either a normal or a high-cholesterol diet. The NS lactobacillus treated groups received the high-cholesterol diet supplemented with Lactobacillus plantarum NS5 or Lactobacillus delbrueckii subsp. bulgaricus NS12 in drinking water. The rats were sacrificed after a 6-week feeding period. Body weights, visceral organ and fat weights, serum and liver cholesterol and lipid levels, intestinal microbiota and liver mRNA expression levels related to cholesterol metabolism were analyzed. Liver lipid deposition and adipocyte size were evaluated histologically. Results Compared with rats fed a high cholesterol diet, serum total cholesterol, low-density lipoprotein cholesterol, apolipoprotein B and free fatty acids levels were decreased and apolipoprotein A-I level was increased in NS5 or NS12 strain treated rats, and with no significant change in high-density lipoprotein cholesterol level. Liver cholesterol and triglyceride levels were also significantly decreased in NS lactobacillus strains treated groups. Meanwhile, the NS lactobacillus strains obviously alleviated hepatic injuries, decreased liver lipid deposition and reduced adipocyte size of high cholesterol diet fed rats. NS lactobacillus strains restored the changes in intestinal microbiota compositions, such as the increase in Bacteroides and the decrease in Clostridium. NS lactobacillus strains also regulated the mRNA expression

The role of beneficial bacteria wall elasticity in regulating innate immune response.

Science.gov (United States)

Мokrozub, Viktoria V; Lazarenko, Liudmyla M; Sichel, Liubov M; Babenko, Lidia P; Lytvyn, Petro M; Demchenko, Olga M; Melnichenko, Yulia O; Boyko, Nadiya V; Biavati, Bruno; DiGioia, Diana; Bubnov, Rostyslav V; Spivak, Mykola Ya

2015-01-01

Probiotics have great potential to contribute to development of healthy dietary regimes, preventive care, and an integrated approach to immunity-related disease management. The bacterial wall is a dynamic entity, depending on many components and playing an essential role in modulating immune response. The impact of cell wall elasticity on the beneficial effects of probiotic strains has not been sufficiently studied. The aim was to investigate the effect of lactic acid bacteria (LAB) and bifidobacteria strains on phagocytic system cells (macrophages) as related to bacterial wall elasticity, estimated using atomic force microscopy (AFM). We conducted studies on Balb/c line mice 18-20 g in weight using lyophilized strains of LAB-Lactobacillus acidophilus IMV B-7279, Lactobacillus casei IMV B-7280, Lactobacillus delbrueckii subsp. bulgaricus IMV B-7281, and bifidobacteria-Bifidobacterium animalis VKL and Bifidobacterium animalis VKB. We cultivated the macrophages obtained from the peritoneal cavity of mice individually with the strains of LAB and bifidobacteria and evaluated their effect on macrophages, oxygen-dependent bactericidal activity, nitric oxide production, and immunoregulatory cytokines. We used AFM scanning to estimate bacterial cell wall elasticity. All strains had a stimulating effect on the functional activity of macrophages and ability to produce NO/NO2 in vitro. Lactobacilli strains increased the production of IL-12 and IFN-γ in vitro. The AFM demonstrated different cell wall elasticity levels in various strains of LAB and bifidobacteria. The rigidity of the cell walls among lactobacilli was distributed as follows: Lactobacillus acidophilus IMV B-7279 > Lactobacillus casei IMV B-7280 > Lactobacillus delbrueckii subsp. bulgaricus IMV B-7281; among the strains of bifidobacteria: B. animalis VKB > B. animalis VKL. Probiotic strain survival in the macrophages depended on the bacterial cell wall elasticity and on the time of their joint cultivation. LAB

Efeito do teor de soro, açúcar e de frutooligossacarídeos sobre a população de bactérias lácticas probióticas em bebidas fermentadas Effect of whey, suggar and frutooligosacharides on the probiotic lactic acid bacteria population in fermented beverages

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Karime Giannetti Thamer

2005-09-01

Full Text Available Nos últimos anos tem havido muito interesse por produtos alimentícios de baixas calorias e probióticos. A incorporação de Lactobacillus acidophilus e Bifidobacterium em bebidas fermentadas pode resultar em um produto lácteo com extraordinário valor terapêutico e eficaz redução calórica. O objetivo deste trabalho foi estudar o efeito do teor de soro, açúcar e de frutooligossacarídeos sobre a população de bactérias lácticas de doze formulações de bebidas fermentadas. Foram determinadas as populações de Streptococcus thermophilus, Lactobacillus delbrueckii subsp. bulgaricus, Bifidobacterium e Lactobacillus acidophilus. As maiores populações de microrganismos probióticos foram observadas nas bebidas com mais baixa acidez e elevado teor de sólidos, além de haver predominância do Streptococcus thermophilus sobre os demais microrganismos. As amostras atenderam a legislação brasileira em vigor, independente das formulações, pela presença de no mínimo 10(6 UFC/mL de bactérias lácticas. As bebidas lácteas formuladas podem ser consideradas probióticas pelas contagens elevadas de Bifidobacterium spp. e Lactobacillus acidophilusThe demand for low calories and probiotics foods has increased during the last years. The incorporation of Lactobacillus acidophilus and Bifidobacterium in fermented beverages can result in dairy products with excellent therapeutic value and efficient calories reduction. The aim of this research was study the effects of whey, sugar and fructooligosaccharides levels on the lactic acid bacteria population of twelve formulations of fermented beverages. The populations of Streptococcus thermophilus, Lactobacillus delbrueckii subsp. bulgaricus, Bifidobacterium spp. and Lactobacillus acidophilus were carried out. The highest probiotic microorganisms' populations were observed in beverages with lower acidity and higher solids level, besides there was a predominance of Streptococcus thermophilus over the

Characterization of goat milk and potentially symbiotic non-fat yogurt

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Noelia Fernanda Paz

2014-09-01

Full Text Available Combining prebiotics and probiotic microorganisms improve quality in the formulation of foods. In this paper, the characteristics of goat milk and symbiotic yogurt were studied. Raw goat milk was analyzed and the skimming process was optimized. For the formulation of a potentially non-fat symbiotic yogurt made with skimmed goat milk, inulin, gelatin, sugar, and Streptococcus salivarius subsp. thermophilus, Lactobacillus delbrueckii subsp. bulgaricus and Lactobacillus casei subsp. rhamnoshus. Chemical characteristics, acceptability, and viability of lactic acid bacteria and probiotic culture were assessed. The protein and fat content of the raw milk was 2.90 and 3.56 g/100 mL, respectively. The optimum skimming process was obtained at 9,800 rpm and 4 °C for 15 minutes. The product formulated had a protein and fat content of 4.04 to 0.04 g/100 mL, good sensory properties, and acceptability of 95%. The lactic bacteria count was 9 × 10(7 CFU mL- 1, and probiotic culture count was higher than 1 × 10(6 CFU mL- 1, which guarantees their effect and capacity to survive in the digestive tract and spread in the intestine. The yogurt was stable during the 21 days of storage. Therefore, this study shows that goat milk yogurt is an adequate delivery vehicle of the probiotic culture L. casei and inulin.

Studying the effect of some growth factors and gamma radiation on the production of polysaccharides by lactic acid bacteria

International Nuclear Information System (INIS)

Mansour, W.S.H.

2008-01-01

using cheese whey as a microbial production medium for exo polysaccharides (EPS) presents a cleaner production opportunity (CPO)to create value-added products and protect the environment. In the present study, fifty lactic acid bacterial strains were isolated from some traditional dairy products including buttermilk, Karish cheese, and yoghurt. The isolates were assessed for EPS production , and three isolates were selected as good EPS producers. When comparing the growth and production kinetics achieved by the selected 3 isolates (Lactobacillus delbrueckii ssp. bulgaricus l1, Lactococcus lactis ssp. cremoris I2, Lactobacillus delbrueckii ssp. Bulgaricus I3) and 3 reference LAB strains including Lactococcus lactis ssp. cremoris DSM 20069, Lactobacillus delbrueckii ssp. bulgaricus EMCC 1102 and Lactobacillus rhamnosus EMCC 1105 in MRS broth and whey based medium (WBM), it was found that reference strains achieved higher growth and EPS productivity than isolates. In addition the growth and productivity achieved in MRS broth were higher than these achieved in WBM. In this study, the optimum nutritional supplements for EPS production in WBM by the studied strains were identified as 100 g/l glucose and 30 g/l yeast extract. In addition, the optimum fermentation conditions were identified as incubation temperature of 37 degree C, initial ph of 6.2 and agitation speed of 50 rpm.

Biochemical Characteristics and Viability of Probiotic and Yogurt Bacteria in Yogurt during the Fermentation and Refrigerated Storage

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F Sarvari

2014-09-01

Full Text Available This research aimed to investigate the viability of probiotic bacteria (Lactobacillus acidophilus LA-5 and Bifidobacterium lactis BB-12 and yogurt bacteria (Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus in yogurt during the fermentation, immediately after fermentation and during refrigerated storage (21 d, 4˚C. Also the biochemical characteristics of milk as affected by the commercial 4-strain mixed starter culture were investigated. Storage time affected the viability of all bacterial species. The concentration of lactic acid during the fermentation increased in parallel with the titrable acidity, and the concentration of acetic acid was proportional to the viability of Bifidobacterium lactis. The acetaldehyde level was decreased in the yogurt from day 0 up to the end of the storage. Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus were multiplied considerably during the fermentation. Streptococcus thermophilus could maintain its viability to the highest level, but Lactobacillus delbrueckii ssp. bulgaricus lost its viability rapidly during the cold storage compared to Streptococcus thermophilus. The multiplication and viability of probiotic bacteria were also influenced by the associative strains and species of yogurt organisms. Bifidobacteria counts were satisfactory. The loss of viability for bifidobacteria was gradual and steady during the storage, and they showed good stability during the storage as compared to Lactobacillus acidophilus.

Improvement of production performance of functional fermented whey-based beverage

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Bulatović Maja Lj.

2014-01-01

Full Text Available The aim of this study was improvement of the performances for the production of whey-based beverages with highly productive strains of Lactobacillus. Individual or mixed culture containing Lactobacillus helveticus ATCC 15009, Lactobacillus delbrueckii ssp. lactis NRRL B-4525 and Streptococcus thermophilus S3 were studied. The scientific hypothesis was that production performances, especially aroma and viable cell count, are positively affected by the strains combination and temperature. Based on the results, beverages obtained by mixed cultures Lb. helveticus ATCC 15009 - S. thermophilus S3 and Lb. delbrueckii ssp. lactis - S. thermophilus S3 had higher aroma values than beverages obtained by individual strains. The symbiosis of tested strains has positive impact on the aroma of produced beverage. In addition, the temperature has significant influence on cell viability during the storage and fermentation dynamic. The beverages produced by mixed cultures Lb. helveticus ATCC 15009 - S. thermophilus S3 and Lb. delbrueckii ssp. lactis - S. thermophilus S3 at 42 oC achieved higher storage stability (19 to 22 days than beverages produced at 37°C and 45°C (13 to 19 days. Subsequently, at 42 °C fermentation time for both mixed cultures was 1.5 h shorter, compared to the time achieved at 37°C.

Use of Probiotics to Control Aflatoxin Production in Peanut Grains

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Juliana Fonseca Moreira da Silva

2015-01-01

Full Text Available Probiotic microorganisms (Saccharomyces cerevisiae var. boulardii, S. cerevisiae UFMG 905, and Lactobacillus delbrueckii UFV H2b20 were evaluated as biological control agents to reduce aflatoxin and spore production by Aspergillus parasiticus IMI 242695 in peanut. Suspensions containing the probiotics alone or in combinations were tested by sprinkling on the grains followed by incubation for seven days at 25°C. All probiotic microorganisms, in live and inactivated forms, significantly reduced A. parasiticus sporulation, but the best results were obtained with live cells. The presence of probiotics also altered the color of A. parasiticus colonies but not the spore morphology. Reduction in aflatoxin production of 72.8 and 65.8% was observed for S. boulardii and S. cerevisiae, respectively, when inoculated alone. When inoculated in pairs, all probiotic combinations reduced significantly aflatoxin production, and the best reduction was obtained with S. boulardii plus L. delbrueckii (96.1% followed by S. boulardii plus S. cerevisiae and L. delbrueckii plus S. cerevisiae (71.1 and 66.7%, resp.. All probiotics remained viable in high numbers on the grains even after 300 days. The results of the present study suggest a different use of probiotics as an alternative treatment to prevent aflatoxin production in peanut grains.

Staphylococcus cohnii subspecies: Staphylococcus cohnii subsp. cohnii subsp. nov. and Staphylococcus cohnii subsp. urealyticum subsp. nov.

Science.gov (United States)

Kloos, W E; Wolfshohl, J F

1991-04-01

Two major subspecies of Staphylococcus cohnii, namely S. cohnii subsp. cohnii, from humans, and S. cohnii subsp. urealyticum, from humans and other primates, are described on the basis of a study of 14 to 25 strains and 18 to 33 strains, respectively. DNA-DNA hybridization studies conducted in our laboratory in 1983 (W. E. Kloos and J. F. Wolfshohl, Curr. Microbiol. 8:115-121, 1983) demonstrated that strains representing the different subspecies were significantly divergent. S. cohnii subsp. urealyticum can be distinguished from S. cohnii subsp. cohnii on the basis of its greater colony size; pigmentation; positive urease, beta-glucuronidase, and beta-galactosidase activities; delayed alkaline phosphatase activity; ability to produce acid aerobically from alpha-lactose; and fatty acid profile. The type strain of S. cohnii subsp. cohnii is ATCC 29974, the designated type strain of S. cohnii Schleifer and Kloos 1975b, 55. The type strain of S. cohnii subsp. urealyticum is ATCC 49330.

Effect of transglutaminase treatment on skimmed yogurt properties

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Iuliana BANU

2012-12-01

Full Text Available The aim of the present study was to evaluate the effect of microbial transglutaminase on the stability and rheological properties of skimmed yogurt. The fermentation was carried out with Streptococus theromophilus and Lactobacillus delbrueckii subsp. Bulgaricus after incubating the milk with various enzyme concentrations ranging from 0 to 0.04%, at different setting temperatures (30, 40 and 50°C, for 60, 90 and 120 min. The postacidification process and the stability of the yogurt samples were influenced by the degree of polymerization of the milk proteins which depended on the conditions of the milk treated with microbial transglutaminase. The best results in terms of whey separation and rheological properties were obtained when preincubating the milk with 0.04% transglutaminase for 120 min setting at 40°C. The results indicate that transglutaminase may be successfully used for enhancing the functional properties of yogurt with low fat content.

Physicochemical and sensory characteristics of a medicinal soy yogurt containing health-benefit ingredients.

Science.gov (United States)

Pyo, Young-Hee; Song, Sun-Mi

2009-01-14

Medicinal soy yogurt (sogurt) containing high levels of gamma-aminobutyric acid (GABA), free amino acids (FAAs), statins, and isoflavone aglycones was developed using lactic acid bacteria (1:1 mixture of Lactobacillus delbrueckii subsp. latis KFRI 01181 and Lactobacillus plantarum KFRI 00144) and Monascus-fermented soybean extract (MFSE, 1.5%, w/v). Changes in the content of some functional components (GABA, FAAs, statins, isoflavones) and physical (pH, titratable acidity, water-holding capacity), biological (viable cell counts), and sensory characteristics of sogurts during fermentation and cold storage were examined. The medicinal sogurt contained significantly (p fermentation for 24 h at 35 degrees C. During cold storage for 30 days at 4 degrees C, medicinal sogurt displayed higher water-holding capacity and titratable acidity and total bacterial cells and lower pH than the control sogurt (p yogurt, resulting in enhanced health-benefit ingredients and consumers' preferences.

Occurrence, isolation and DNA identification of Streptococcus ...

African Journals Online (AJOL)

ajl yemi

2011-11-28

Nov 28, 2011 ... Streptococcus thermophilus involved in Algerian ... among reference, and wild strains of S. thermophilus and for their differentiation from Enterococcus spp. ..... Isolation and characterization of Lactobacillus delbrueckii ssp.

Effect of ratio variation of crop wastes on the production of poultry ...

African Journals Online (AJOL)

Proteus mirabilis, Proteus morganii, Enterobacter aerogenes, Klebsiella pneumoniae, Pseudomonas aeruginosa, Bacillus subtilis, Bacillus licheniformis, Acetobacter orleanensis, Clostridium butyricum, Micrococcus roseus, Lactobacillus delbrueckii, Clostridium spheroides, and Methanobacillus species. Seven fungal ...

Enhancement productivity of lactic acid bacteria (LAB) to produced ex polysaccharide

International Nuclear Information System (INIS)

EL-Fouly, M.; Meleigy, S.A; Hendawy, W.S.; Magdoub, M.I.N.; Aita, O.A.

2010-01-01

Isolation and characterization of exo cellular polysaccharide was studied in order to evaluate some parameters in the synthesis of exo polysaccharide (EPS) and improve their production through submerged fermentation processes. Isolation strains Lactobacillus delbrueckii ssp bulgaricus (IS1), Lactococcus lactis ssp cremoris (IS2) and Lactobacillus delbrueckii ssp bulgaricus (IS3) were studied in shake flasks using yeast extract, surfactants and different exposure doses of gamma irradiation. The optimum concentration of (EPS) formation (0.762 g/l) by Lactococcus lactis ssp cremoris (IS2) at and 3.0(g/l) yeast extract, 1.72 (g/l) at 0.5 (%) surfactant Triton X-100. Also, EPS (1.842 g/l) was produced when Lactococcus lactis ssp cremoris (IS2) exposed to 0.2 kGy dose level

Isolation and Characterization of Lactic Acid Bacteria (LAB) Produced Exo cellular Polysaccharide

International Nuclear Information System (INIS)

Meleigy, S.A.; Hendawy, W.S.

2009-01-01

Isolation and characterization of exo cellular polysaccharide was studied in order to evaluate some parameters in the synthesis of exo polysaccharide (EPS) and improve their production through submerged fermentation processes. Isolation strains Lactobacillus delbrueckii ssp bulgaricus (IS 1 ), Lactococcus lactis ssp cremoris (IS 2 ) and Lactobacillus delbrueckii ssp bulgaricus (IS 3 ) were studied in shake flasks using yeast extract, surfactants and different exposure doses of gamma irradiation.The optimum concentration of (EPS) formation (0.762 g/l) by Lactococcus lactis ssp cremoris (IS 2 ), 3.0 (g/l) yeast extract, 1.72 (g/l) at 0.5 (%) surfactant Triton X-100. Also, EPS (1.842 g/l) was produced when Lactococcus lactis ssp cremoris (IS 2 ) exposed to 0.2 kGy dose level.

Characterization of Probiotic Fermented Milk Prepared by Different Inoculation Size of Mesophilic and Thermophilic Lactic Acid Bacteria

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Sara Nasiri Boosjin

2016-10-01

Full Text Available Background and Objectives: Importance of development of novel probiotic fermented milk and challenge made for its acceptability is well known. In this research, the impact of different inoculation sizes of yogurt and DL-type starter culture (mesophilic and thermophilic LAB on titratable acidity, viscosity, sensorial and microbial properties of fermented milk was investigated; and finally, probiotic Langfil was produced.Materials and Methods: Fermented milk produced by 1, 2 and 3% v v-1 inocula consisting thermophilic: mesophilic starter cultures 10:90 (Lactococcus lactis subsp. lactis, Lactococcus lactis subsp. cremoris, Lactococcus lactis subsp. lactis, Lactococcus lactis subsp. lactis biovar. diacetylactis and Leuconostoc mesenteroides subsp. cremoris. Streptococcus thermophilus and Lactobacillus delbrueckii subsp. Bulgaricus were analyzed for determination of titratable acidity, viscosity, viability of mesophilic starter cultures and sensory properties on days 5, 10, and 15 of storage at 4°C. Then, the most suitable treatments were selected for the producing probiotic Langfil, containing probiotic starter culture (2% v v-1 inoculums with equal ratio of Lactobacillus acidophilus and Bifidobacterium bifidum. Lactococcus lactis and L. cremoris were counted on M17 agar, while Leuconostoc and Lactobacillus were counted aerobically on tomato juice agar and MRS bile agar, respectively. Bifidobacterium was cultured anaerobically on MRS bile agar. Sensory evaluation was carried out by ten trained panelists, based on a nine-point hedonic scale during the cold storage.Results and Conclusion: According to results, the best organoleptic properties were achieved in the product prepared with 2% the mesophilic and thermophilic starter cultures and 2% probiotic. This product had a high viscosity. An Iranian probiotic Langfil with desired properties was produced using the best treatment prepared.Conflict of interests: The authors declare no conflict of

Optimization of the quenching method for metabolomics analysis of Lactobacillus bulgaricus.

Science.gov (United States)

Chen, Ming-ming; Li, Ai-li; Sun, Mao-cheng; Feng, Zhen; Meng, Xiang-chen; Wang, Ying

2014-04-01

This study proposed a quenching protocol for metabolite analysis of Lactobacillus delbrueckii subsp. bulgaricus. Microbial cells were quenched with 60% methanol/water, 80% methanol/glycerol, or 80% methanol/water. The effect of the quenching process was assessed by the optical density (OD)-based method, flow cytometry, and gas chromatography-mass spectrometry (GC-MS). The principal component analysis (PCA) and orthogonal partial least squares-discriminant analysis (OPLS-DA) were employed for metabolite identification. The results indicated that quenching with 80% methanol/water solution led to less damage to the L. bulgaricus cells, characterized by the lower relative fraction of prodium iodide (PI)-labeled cells and the higher OD recovery ratio. Through GC-MS analysis, higher levels of intracellular metabolites (including focal glutamic acid, aspartic acid, alanine, and AMP) and a lower leakage rate were detected in the sample quenched with 80% methanol/water compared with the others. In conclusion, we suggested a higher concentration of cold methanol quenching for L. bulgaricus metabolomics due to its decreasing metabolite leakage.

Dairy Streptococcus thermophilus improves cell viability of Lactobacillus brevis NPS-QW-145 and its γ-aminobutyric acid biosynthesis ability in milk

Science.gov (United States)

Wu, Qinglong; Law, Yee-Song; Shah, Nagendra P.

2015-01-01

Most high γ-aminobutyric acid (GABA) producers are Lactobacillus brevis of plant origin, which may be not able to ferment milk well due to its poor proteolytic nature as evidenced by the absence of genes encoding extracellular proteinases in its genome. In the present study, two glutamic acid decarboxylase (GAD) genes, gadA and gadB, were found in high GABA-producing L. brevis NPS-QW-145. Co-culturing of this organism with conventional dairy starters was carried out to manufacture GABA-rich fermented milk. It was observed that all the selected strains of Streptococcus thermophilus, but not Lactobacillus delbrueckii subsp. bulgaricus, improved the viability of L. brevis NPS-QW-145 in milk. Only certain strains of S. thermophilus improved the gadA mRNA level in L. brevis NPS-QW-145, thus enhanced GABA biosynthesis by the latter. These results suggest that certain S. thermophilus strains are highly recommended to co-culture with high GABA producer for manufacturing GABA-rich fermented milk. PMID:26245488

THE EFFECT OF TRANSGLUTAMINASE ON THE RHEOLOGICAL PROPERTIES OF YOGURT

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Iuliana Aprodu

2011-05-01

Full Text Available The aim of this study was to investigate the rheological characteristics of yogurts obtained from milk treated with transglutaminase prior to fermentation with Streptococus theromophilus and Lactobacillus delbrueckii subsp. Bulgaricus. A set of 36 experiments were carried out to test the influence of various enzyme concentrations ranging from 0 to 0.04%, different setting temperatures (35, 40 and 45 oC, and setting time (60, 90 and 120 min. The cross-linking of milk proteins influenced the post-acidification process as well as the stability of the yogurt samples. The enzymatic treatment of milk allowed avoiding the syneresis phenomena during yogurt storage at 4 oC; the water holding capacity during centrifugation was also improved. Concerning the rheological properties, the apparent viscosity of yogurt increased by increasing the enzyme concentration and the setting time for the entire tested domain of shear rates. The results indicate that transglutaminase catalyzed cross-linking is an effective tool for improving functional properties of yogurt.

Separation of Oligosaccharides from Lotus Seeds via Medium-pressure Liquid Chromatography Coupled with ELSD and DAD

Science.gov (United States)

Lu, Xu; Zheng, Zhichang; Miao, Song; Li, Huang; Guo, Zebin; Zhang, Yi; Zheng, Yafeng; Zheng, Baodong; Xiao, Jianbo

2017-03-01

Lotus seeds were identified by the Ministry of Public Health of China as both food and medicine. One general function of lotus seeds is to improve intestinal health. However, to date, studies evaluating the relationship between bioactive compounds in lotus seeds and the physiological activity of the intestine are limited. In the present study, by using medium pressure liquid chromatography coupled with evaporative light-scattering detector and diode-array detector, five oligosaccharides were isolated and their structures were further characterized by electrospray ionization-mass spectrometry and gas chromatography-mass spectrometry. In vitro testing determined that LOS3-1 and LOS4 elicited relatively good proliferative effects on Lactobacillus delbrueckii subsp. bulgaricus. These results indicated a structure-function relationship between the physiological activity of oligosaccharides in lotus seeds and the number of probiotics applied, thus providing room for improvement of this particular feature. Intestinal probiotics may potentially become a new effective drug target for the regulation of immunity.

Screening of potential lactobacilli antigenotoxicity by microbial and mammalian cell-based tests.

Science.gov (United States)

Caldini, G; Trotta, F; Villarini, M; Moretti, M; Pasquini, R; Scassellati-Sforzolini, G; Cenci, G

2005-06-25

Antigenotoxicity is considered an important property for probiotic lactobacilli. The ability of non probiotic lactobacilli from dairy products and starters to inhibit two reference genotoxins: 4-nitroquinoline-1-oxide and N-methyl-N'-nitro-N-nitrosoguanidine was evaluated. The study was carried out using short-term assays with different targets, such as procaryotic cells (SOS-Chromotest for genotoxicity in Escherichia coli and Ames test for mutagenicity in Salmonella typhimurium) and eucaryotic cells (Comet assay for genotoxicity in Caco-2 enterocytes). A high proportion of strains inhibiting 4-nitroquinoline-1-oxide activity was found in Lactobacillus casei, Lactobacillus acidophilus, Lactobacillus rhamnosus, Lactobacillus delbrueckii subsp. bulgaricus and Lactobacillus plantarum. Inhibition of N-methyl-N'-nitro-N-nitrosoguanidine activity occurred in only one L. acidophilus strain. All the strains with antigenotoxic properties also demonstrated antimutagenic activity and produced modifications in genotoxin spectroscopic profiles. Strain viability during and after genotoxin exposure was confirmed. Concordance of the results obtained with microbial and mammalian cell-based tests is underlined.

Dairy Streptococcus thermophilus improves cell viability of Lactobacillus brevis NPS-QW-145 and its γ-aminobutyric acid biosynthesis ability in milk.

Science.gov (United States)

Wu, Qinglong; Law, Yee-Song; Shah, Nagendra P

2015-08-06

Most high γ-aminobutyric acid (GABA) producers are Lactobacillus brevis of plant origin, which may be not able to ferment milk well due to its poor proteolytic nature as evidenced by the absence of genes encoding extracellular proteinases in its genome. In the present study, two glutamic acid decarboxylase (GAD) genes, gadA and gadB, were found in high GABA-producing L. brevis NPS-QW-145. Co-culturing of this organism with conventional dairy starters was carried out to manufacture GABA-rich fermented milk. It was observed that all the selected strains of Streptococcus thermophilus, but not Lactobacillus delbrueckii subsp. bulgaricus, improved the viability of L. brevis NPS-QW-145 in milk. Only certain strains of S. thermophilus improved the gadA mRNA level in L. brevis NPS-QW-145, thus enhanced GABA biosynthesis by the latter. These results suggest that certain S. thermophilus strains are highly recommended to co-culture with high GABA producer for manufacturing GABA-rich fermented milk.

Characterization of pMC11, a plasmid with dual origins of replication isolated from Lactobacillus casei MCJ and construction of shuttle vectors with each replicon

DEFF Research Database (Denmark)

Chen, Zhengjun; Lin, Jinzhong; Ma, Chengjie

2014-01-01

. These plasmids showed distinct properties: pEL5.7 was capable of replicating in L. casei MCJΔ1 and Lactobacillus delbrueckii subsp. lactic LBCH-1 but failed to do so in two other tested lactobacilli strains whereas pEL5.6 replicated in three different strains, including L. casei MCJΔ1, L. casei NJ, Lactobacillus......Many lactic acid bacteria carry different plasmids, particularly those that replicate via a theta mechanism. Here we describe Lactobacillus casei MCJ(CCTCC AB20130356), a new isolate that contains pMC11, carrying two distinct theta-type replicons. Each replicon contained an iteron in the origin...... of replication (oriV1 or oriV2) and a gene coding for the replicase (RepA_1 or RepB_1), both of which are essential for plasmid replication. Escherichia coli/Lactobacillus shuttle vectors were constructed with each replicon, yielding pEL5.7 and pEL5.6 that are based on oriV2 and oriV1 replicons, respectively...

Antioxidant Activity of Whey from Milk Fermented with Lactobacillus Species Isolated from Nigerian Fermented Foods

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Ifeoma Korie

2010-01-01

Full Text Available Eight Lactobacillus isolates obtained from five indigenous fermented foods (ogi, ogi baba, wara, kunnu and ugba were investigated. Wara is a dairy-based food while the others are not dairy-based. The bacteria were isolated on MRS agar and purified by successive streaking on the same medium. The whey fraction of skimmed milk fermented with each isolate was assayed for radical scavenging effects using 2,2-diphenyl-1-picrylhydrazyl (DPPH radical. All the whey fractions showed radical scavenging activities. The five isolates with the highest activities were selected. On the basis of Gram stain reaction, cellular morphology, biochemical tests and carbohydrate utilization profiles they were identified as strains of Lactobacillus brevis, L. fermentum, L. plantarum, L. casei and L. delbrueckii. The antioxidant activities of whey fractions from 24-hour fermentations with the selected organisms were investigated using both radical scavenging effects and lipid peroxidation inhibitory activity. The radical scavenging activity was generally higher than the lipid peroxidation inhibition, except in the L. plantarum strain, which did not show any significant difference in both activities. The probiotic potential of the isolates was evaluated by pH and bile tolerance. None of the selected isolates showed any growth at pH=2.0 but L. casei and L. delbrueckii survived at this pH. Four of the five selected isolates were able to grow in 0.5 % dehydrated bile, with L. casei strain showing the highest level of growth, followed by L. delbrueckii. L. plantarum strain was not bile tolerant. The ability of L. casei and L. delbrueckii strains to survive at pH=2 and grow in the presence of bile indicates that the isolates may be able to colonize the gastrointestinal tract. The findings of this study indicate that Lactobacillus strains isolated from indigenous Nigerian fermented foods could be useful as starter cultures to provide antioxidants in food and that fermented milk

Production of a Functional Frozen Yogurt Fortified with Bifidobacterium spp.

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Abdelazez, Amro; Muhammad, Zafarullah; Zhang, Qiu-Xue; Zhu, Zong-Tao; Abdelmotaal, Heba; Sami, Rokayya; Meng, Xiang-Chen

2017-01-01

Frozen dairy products have characteristics of both yogurt and ice cream and could be the persuasive carriers of probiotics. Functions of the frozen yogurt containing viable bifidobacterial cells are recognized and favored by the people of all ages. We developed a kind of yogurt supplemented by Bifidobacterium species. Firstly, five strains of Bifidobacterium spp. ( Bifidobacterium bifidum ATCC 11547, Bifidobacterium longum ATCC 11549, Bifidobacterium infantis ATCC 11551, Bifidobacterium adolescentis ATCC 11550, and Bifidobacterium breve ATCC 11548) were evaluated based on the feasibility criteria of probiotics, comprising acid production, bile tolerance, and adhesion to epithelial cells. Formerly, we combined the optimum strains with yogurt culture ( Lactobacillus delbrueckii subsp. bulgaricus EMCC 11102 and Streptococcus salivarius subsp. thermophilus EMCC 11044) for producing frozen yogurt. Finally, physiochemical properties and sensory evaluation of the frozen yogurt were investigated during storage of 60 days at -18°C. Results directed that Bifidobacterium adolescentis ATCC 11550 and Bifidobacterium infantis ATCC 11551 could be utilized with yogurt culture for producing frozen yogurt. Moreover, the frozen yogurt fermented by two bifidobacterial strains and yogurt culture gained the high evaluation in the physiochemical properties and sensory evaluation. In summary, our results revealed that there was no significant difference between frozen yogurt fermented by Bifidobacterium spp. and yogurt culture and that fermented by yogurt culture only.

Antibiotic resistance of lactic acid bacteria and Bifidobacterium spp. isolated from dairy and pharmaceutical products.

Science.gov (United States)

D'Aimmo, Maria Rosaria; Modesto, Monica; Biavati, Bruno

2007-04-01

The outlines of antibiotic resistance of some probiotic microorganisms were studied. This study was conducted with the double purpose of verifying their ability to survive if they are taken simultaneously with an antibiotic therapy and to increase the selective properties of suitable media for the isolation of samples containing mixed bacterial populations. We isolated from commercial dairy and pharmaceutical products, 34 strains declared as probiotics, belonging to the genera Bifidobacterium and Lactobacillus, and 21 strains of starter culture bacteria. All the microorganisms have been compared by electrophoresis of the soluble proteins for the purpose of identifying them. A Multiplex-PCR with genus- and species-specific primers was used to detect for Bifidobacterium animalis subsp. lactis presence. All bifidobacteria were B. animalis subsp. lactis except one Bifidobacterium longum. Sometimes the identification showed that the used strain was not the one indicated on the label. The lactobacilli were Lactobacillus acidophilus, Lactobacillus casei, and Lactobacillus delbrueckii subsp. bulgaricus. The streptococci were all Streptococcus thermophilus. The minimal inhibitory concentration (MIC) of 24 common antibiotic substances has been valued by the broth microdilution method. All tested strains were susceptible to ampicillin, bacitracin, clindamycin, dicloxacillin, erytromycin, novobiocin, penicillin G, rifampicin (MIC(90) ranging from 0.01 to 4 microg/ml); resistant to aztreonam, cycloserin, kanamycin, nalidixic acid, polymyxin B and spectinomycin (MIC(90) ranging from 64 to >1000 microg/ml). The susceptibility to cephalothin, chloramphenicol, gentamicin, lincomycin, metronidazole, neomycin, paromomycin, streptomycin, tetracycline and vancomycin was variable and depending on the species.

Effects of yogurt fermented with Lactobacillus delbrueckii ssp. bulgaricus OLL1073R-1 on the IgA flow rate of saliva in elderly persons residing in a nursing home: A before-after non-randomised intervention study.

Science.gov (United States)

Yamamoto, Yuko; Fujino, Kazuhiro; Saruta, Juri; Takahashi, Toru; To, Masahiro; Fuchida, Shinya; Shimizu, Tomoko; Kamata, Yohei; Misawa, Kyoko; Tsukinoki, Keiichi

2017-12-01

The aim of this study was to investigate the alterations in the salivary IgA levels of elderly persons administered yogurt fermented with Lactobacillus delbrueckii ssp. bulgaricus (L. bulgaricus) OLL1073R-1, which has been reported to reduce the risk of colds. Salivary immunoglobulin (Ig)A plays an important role in the defence of the oral cavity mucous membrane against foreign antigens and pathogens. Accordingly, low levels of salivary IgA are associated with an increased risk of upper respiratory tract infection. Furthermore, salivary IgA secretion has been reported to decrease with age. Recently, several studies have reported that certain strains of Lactobacillus and their products can modulate the immune response, but there are currently few studies on the effects of on the IgA level in human saliva. This was a before-after non-randomised intervention study. Thirty-seven elderly persons (mean age, 82.7 years) residing in a single nursing home ingested 112 g of the yogurt every morning for 12 weeks. The participants' saliva was collected before and after 4, 8 and 12 weeks of yogurt intake. Our results showed that yogurt intake affected the concentration of IgA in the saliva (P < .0001). Additionally, yogurt intake and the body weight of the participants affected the IgA flow rate of saliva (P = .0003 and .03, respectively). Continuous intake of yogurt fermented with L. bulgaricus OLL1073R-1 may help improve the mucosal immune function in elderly people with weakened immune systems. © 2017 John Wiley & Sons A/S and The Gerodontology Association. Published by John Wiley & Sons Ltd.

Influence of starter culture of lactic acid bacteria on the shelf life of ...

African Journals Online (AJOL)

A total of eight lactic acid bacteria were isolated from various fermented cereal gruels (ogi). They were identified as Lactobacillus plantarum, Lactobacillus casei, Leuconostoc mesenteroides, Lactobacillus brevis, Lactobacillus fermentum, Lactobacillus delbrueckii, Lactobacillus acidophilus and Pediococcus acidilactici.

Screening of antimicrobial activity of lactic acid bacteria isolated ...

African Journals Online (AJOL)

They were identified as Lactobacillus fermentum (46%), L. plantarum (23%),. Enterococcus ... specific yoghurt-like sour flavor that distinguishes it .... 5 µl of each primer (10 pmol µl-1), 0.125 µl of. Ex-Taq ... Lactobacillus delbrueckii. F/31. MRS ...

Identification of exopolysaccharides-producing lactic acid bacteria ...

African Journals Online (AJOL)

Spacer region between 16S and 23 S rRNA genes of thirteen lactic acid bacteria strains from Burkina Faso fermented milk samples were amplified by the polymerase chain reaction (PCR). Lactobacillus delbrueckii, Lactobacillus acidophilus, Lactobacillus fermentum, Streptococcus thermophilus, Pediococcus spp, ...

Production of a Functional Frozen Yogurt Fortified with Bifidobacterium spp.

Science.gov (United States)

Muhammad, Zafarullah; Zhang, Qiu-Xue; Zhu, Zong-Tao

2017-01-01

Frozen dairy products have characteristics of both yogurt and ice cream and could be the persuasive carriers of probiotics. Functions of the frozen yogurt containing viable bifidobacterial cells are recognized and favored by the people of all ages. We developed a kind of yogurt supplemented by Bifidobacterium species. Firstly, five strains of Bifidobacterium spp. (Bifidobacterium bifidum ATCC 11547, Bifidobacterium longum ATCC 11549, Bifidobacterium infantis ATCC 11551, Bifidobacterium adolescentis ATCC 11550, and Bifidobacterium breve ATCC 11548) were evaluated based on the feasibility criteria of probiotics, comprising acid production, bile tolerance, and adhesion to epithelial cells. Formerly, we combined the optimum strains with yogurt culture (Lactobacillus delbrueckii subsp. bulgaricus EMCC 11102 and Streptococcus salivarius subsp. thermophilus EMCC 11044) for producing frozen yogurt. Finally, physiochemical properties and sensory evaluation of the frozen yogurt were investigated during storage of 60 days at −18°C. Results directed that Bifidobacterium adolescentis ATCC 11550 and Bifidobacterium infantis ATCC 11551 could be utilized with yogurt culture for producing frozen yogurt. Moreover, the frozen yogurt fermented by two bifidobacterial strains and yogurt culture gained the high evaluation in the physiochemical properties and sensory evaluation. In summary, our results revealed that there was no significant difference between frozen yogurt fermented by Bifidobacterium spp. and yogurt culture and that fermented by yogurt culture only. PMID:28691028

Farklı İnkübasyon Sonu Asitliğinin Ayran Kalitesine Etkisi

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Balkır Tamuçay-Özünlü

2015-02-01

Full Text Available Bu çalışmada, ayran üretimi sırasında farklı pH’larda (4.6, 4.3 ve 4.0 pH inkübasyonu sonlandırmanın, ayranın fiziksel, kimyasal, mikrobiyolojik ve duyusal nitelikleri üzerine olan etkileri incelenmiştir. Depolamanın tüm dönemlerinde (1., 7. ve 14. günler en düşük pH (4.0 pH değerlerine sahip ayran örneği, en yüksek titrasyon asitliği ve laktik asit değerlerini göstermiştir. Farklı inkübasyon çıkış pH’larının örneklerin pH, titrasyon asitliği, laktik asit içeriği, serum ayrılması (P<0.01, asetaldehit içeriği ve viskozite değerleri (P<0.05 ile Lactobacillus delbrueckii subsp. bulgaricus sayısı üzerine etkisi önemli bulunurken (P<0.01, Streptococcus salivarius subsp. thermophilus sayısı (P>0.01 ile tat, aroma ve kıvam gibi duyusal özellikleri üzerine olan etkisinin ise önemli olmadığı (P>0.05 belirlenmiştir.

Molecular characterization of Lactobacillus plantarum DMDL 9010, a strain with efficient nitrite degradation capacity.

Science.gov (United States)

Fei, Yong-tao; Liu, Dong-mei; Luo, Tong-hui; Chen, Gu; Wu, Hui; Li, Li; Yu, Yi-gang

2014-01-01

Nitrites commonly found in food, especially in fermented vegetables, are potential carcinogens. Therefore, limiting nitrites in food is critically important for food safety. A Lactobacillus strain (Lactobacillus sp. DMDL 9010) was previously isolated from fermented vegetables by our group, and is not yet fully characterized. A number of phenotypical and genotypical approaches were employed to characterize Lactobacillus sp. DMDL 9010. Its nitrite degradation capacity was compared with four other Lactobacillus strains, including Lactobacillus casei subsp. rhamnosus 719, Lactobacillus delbrueckii subsp. bulgaricu 1.83, Streptococcus thermophilus 1.204, and lactobacillus plantarum 8140, on MRS medium. Compared to these four Lactobacillus strains, Lactobacillus sp. DMDL 9010 had a significantly higher nitrite degradation capacity (PLactobacillus sp. DMDL 9010 was identified as either Lactobacillus plantarum or Lactobacillus pentosus. To further identify this strain, the flanking regions (922 bp and 806 bp upstream and downstream, respectively) of the L-lactate dehydrogenase 1 (L-ldh1) gene were amplified and sequenced. Lactobacillus sp. DMDL 9010 had 98.92 and 76.98% sequence identity in the upstream region with L. plantarum WCFS1 and L. pentosus IG1, respectively, suggesting that Lactobacillu sp. DMDL 9010 is an L. plantarum strain. It was therefore named L. plantarum DMDL 9010. Our study provides a platform for genetic engineering of L. plantarum DMDL 9010, in order to further improve its nitrite degradation capacity.

Production of a Functional Frozen Yogurt Fortified with Bifidobacterium spp.

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Amro Abdelazez

2017-01-01

Full Text Available Frozen dairy products have characteristics of both yogurt and ice cream and could be the persuasive carriers of probiotics. Functions of the frozen yogurt containing viable bifidobacterial cells are recognized and favored by the people of all ages. We developed a kind of yogurt supplemented by Bifidobacterium species. Firstly, five strains of Bifidobacterium spp. (Bifidobacterium bifidum ATCC 11547, Bifidobacterium longum ATCC 11549, Bifidobacterium infantis ATCC 11551, Bifidobacterium adolescentis ATCC 11550, and Bifidobacterium breve ATCC 11548 were evaluated based on the feasibility criteria of probiotics, comprising acid production, bile tolerance, and adhesion to epithelial cells. Formerly, we combined the optimum strains with yogurt culture (Lactobacillus delbrueckii subsp. bulgaricus EMCC 11102 and Streptococcus salivarius subsp. thermophilus EMCC 11044 for producing frozen yogurt. Finally, physiochemical properties and sensory evaluation of the frozen yogurt were investigated during storage of 60 days at −18°C. Results directed that Bifidobacterium adolescentis ATCC 11550 and Bifidobacterium infantis ATCC 11551 could be utilized with yogurt culture for producing frozen yogurt. Moreover, the frozen yogurt fermented by two bifidobacterial strains and yogurt culture gained the high evaluation in the physiochemical properties and sensory evaluation. In summary, our results revealed that there was no significant difference between frozen yogurt fermented by Bifidobacterium spp. and yogurt culture and that fermented by yogurt culture only.

Filtration behaviors of rod-shaped bacterial broths in unsteady-state phase of cross-flow filtration

Energy Technology Data Exchange (ETDEWEB)

Tanaka, T.; Usui, K.; Koda, K.; Nakanishi, K. [Okayama University, Okayama (Japan). Faculty of Engineering

1996-12-20

Filtration behaviors in the unsteady-state phase of crossflow filtration of broths of Bacillus subtilis, Escherichia coli, and Lactobacillus delbrueckii, which are rod-shaped, were studied from the viewpoint of the changes in the specific resistance and in the structure of the microbial cake formed on the membrane surface. The permeation flux followed the cake filtration law at the initial stage of the crossflow filtration of the broths of B. subtilis and E. coli, where the cells deposited randomly on the membrane. In the case of the crossflow filtration of a L. delbrueckii broth, the period of random deposition was shorter. The specific resistance for the cake formed at the initial stage agreed with that measured in dead-end filtration. Then, the specific resistance started to increase in comparison with that measured in dead-end filtration due to shear-induced arrangement of the cells. The extent of the increase in specific resistance became higher and the time taken to start the cell arrangement became shorter with increasing circulation flow rate. The increase in specific resistance due to the shear-induced arrangement was more appreciable in the crossflow filtration of the broth of L. delbrueckii than that of B. subtilis and E. coli. The average permeation flux was increased considerably by applying periodical backwashing with appropriate time intervals. The permeation flux was well predicted by the cake filtration law, since the cells deposited in a way similar to that for dead-end filtration during a sufficiently short period of crossflow filtration in a backwashing mode. 21 refs., 11 figs.

Antagonistic effect of Lactobacillus strains against gas-producing coliforms isolated from colicky infants

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Oggero Roberto

2011-06-01

Full Text Available Abstract Background Infantile colic is a common disturb within the first 3 months of life, nevertheless the pathogenesis is incompletely understood and treatment remains an open issue. Intestinal gas production is thought to be one of the causes of abdominal discomfort in infants suffering from colic. However, data about the role of the amount of gas produced by infants' colonic microbiota and the correlation with the onset of colic symptoms are scanty. The benefit of supplementation with lactobacilli been recently reported but the mechanisms by which they exert their effects have not yet been fully defined. This study was performed to evaluate the interaction between Lactobacillus spp. strains and gas-forming coliforms isolated from stools of colicky infants. Results Strains of coliforms were isolated from stools of 45 colicky and 42 control breastfed infants in McConkey Agar and identified using PCR with species-specific primers, and the BBL™ Enterotube™ II system for Enterobacteriaceae. Gas-forming capability of coliforms was assessed in liquid cultures containing lactose as sole carbon source. The average count of total coliforms in colicky infants was significantly higher than controls: 5.98 (2.00-8.76 log10 vs 3.90 (2.50-7.10 CFU/g of faeces (p = 0.015. The following strains were identified: Escherichia coli, Klebsiella pneumoniae, Klebsiella oxytoca, Enterobacter aerogenes, Enterobacter cloacae and Enterococcus faecalis. Then, 27 Lactobacillus strains were tested for their antagonistic effect against coliforms both by halo-forming method and in liquid co-cultures. Lactobacillus delbrueckii subsp.delbrueckii DSM 20074 and L. plantarum MB 456 were able to inhibit all coliforms strains (halo-forming method, also in liquid co-cultures, thus demonstrating an antagonistic activity. Conclusions This study shows that two out of 27 strains of Lactobacillus examined possess an antimicrobial effect against six species of gas-forming coliforms

Antagonistic effect of Lactobacillus strains against gas-producing coliforms isolated from colicky infants.

Science.gov (United States)

Savino, Francesco; Cordisco, Lisa; Tarasco, Valentina; Locatelli, Emanuela; Di Gioia, Diana; Oggero, Roberto; Matteuzzi, Diego

2011-06-30

Infantile colic is a common disturb within the first 3 months of life, nevertheless the pathogenesis is incompletely understood and treatment remains an open issue. Intestinal gas production is thought to be one of the causes of abdominal discomfort in infants suffering from colic. However, data about the role of the amount of gas produced by infants' colonic microbiota and the correlation with the onset of colic symptoms are scanty. The benefit of supplementation with lactobacilli been recently reported but the mechanisms by which they exert their effects have not yet been fully defined. This study was performed to evaluate the interaction between Lactobacillus spp. strains and gas-forming coliforms isolated from stools of colicky infants. Strains of coliforms were isolated from stools of 45 colicky and 42 control breastfed infants in McConkey Agar and identified using PCR with species-specific primers, and the BBL™ Enterotube™ II system for Enterobacteriaceae. Gas-forming capability of coliforms was assessed in liquid cultures containing lactose as sole carbon source. The average count of total coliforms in colicky infants was significantly higher than controls: 5.98 (2.00-8.76) log10 vs 3.90 (2.50-7.10) CFU/g of faeces (p = 0.015). The following strains were identified: Escherichia coli, Klebsiella pneumoniae, Klebsiella oxytoca, Enterobacter aerogenes, Enterobacter cloacae and Enterococcus faecalis. Then, 27 Lactobacillus strains were tested for their antagonistic effect against coliforms both by halo-forming method and in liquid co-cultures. Lactobacillus delbrueckii subsp. delbrueckii DSM 20074 and L. plantarum MB 456 were able to inhibit all coliforms strains (halo-forming method), also in liquid co-cultures, thus demonstrating an antagonistic activity. This study shows that two out of 27 strains of Lactobacillus examined possess an antimicrobial effect against six species of gas-forming coliforms isolated from colicky infants. Our findings may stimulate

The determination of the first normal stress coefficient of an exopolysaccharide solution by rheo-optical measurements

NARCIS (Netherlands)

Zarzycki, R.; Linden, van der E.; Sagis, L.M.C.; Venema, P.; Babuchowski, A.

2004-01-01

Abstract This paper illustrates how rheo-optical techniques may be utilized to determine the first normal stress coefficient for an exopolysaccharide (EPS) produced by the Lactobacillus delbrueckii ssp. bulgaricus LY03, which is widely used in yoghurt production. In this technique both shear stress,

Optimization of the quenching method for metabolomics analysis of Lactobacillus bulgaricus *

Science.gov (United States)

Chen, Ming-ming; Li, Ai-li; Sun, Mao-cheng; Feng, Zhen; Meng, Xiang-chen; Wang, Ying

2014-01-01

This study proposed a quenching protocol for metabolite analysis of Lactobacillus delbrueckii subsp. bulgaricus. Microbial cells were quenched with 60% methanol/water, 80% methanol/glycerol, or 80% methanol/water. The effect of the quenching process was assessed by the optical density (OD)-based method, flow cytometry, and gas chromatography-mass spectrometry (GC-MS). The principal component analysis (PCA) and orthogonal partial least squares-discriminant analysis (OPLS-DA) were employed for metabolite identification. The results indicated that quenching with 80% methanol/water solution led to less damage to the L. bulgaricus cells, characterized by the lower relative fraction of prodium iodide (PI)-labeled cells and the higher OD recovery ratio. Through GC-MS analysis, higher levels of intracellular metabolites (including focal glutamic acid, aspartic acid, alanine, and AMP) and a lower leakage rate were detected in the sample quenched with 80% methanol/water compared with the others. In conclusion, we suggested a higher concentration of cold methanol quenching for L. bulgaricus metabolomics due to its decreasing metabolite leakage. PMID:24711354

Growth of probiotic bacteria and bifidobacteria in a soy yogurt formulation.

Science.gov (United States)

Farnworth, E R; Mainville, I; Desjardins, M-P; Gardner, N; Fliss, I; Champagne, C

2007-05-01

Soy beverage and cows' milk yogurts were produced with Steptococcus thermophilus (ATCC 4356) and Lactobacillus delbrueckii subsp. bulgaricus (IM 025). The drop in pH during fermentation was faster in the soy beverage than in cows' milk, but the final pH values were similar. Yogurts were prepared with a yogurt starter in conjunction with either the probiotic bacteria Lactobacillus johnsonii NCC533 (La-1), Lactobacillus rhamnosus ATCC 53103 (GG) or human derived bifidobacteria. The presence of the probiotic bacteria did not affect the growth of the yogurt strains. Approximately 2 log increases in both L. rhamnosus GG and L. johnsonii La-1 were observed when each was added with the yogurt strains in both cows' milk and the soy beverage. Two of the five bifidobacteria strains grew well in the cows' milk and soy beverage during fermentation with the yogurt bacteria. High pressure liquid chromatography (HPLC) analyses showed that the probiotic bacteria and the bifidobacteria were using different sugars to support their growth, depending on whether the bacteria were growing in cows' milk or soy beverage.

Fructanase and fructosyltransferase activity of non-Saccharomyces yeasts isolated from fermenting musts of Mezcal.

Science.gov (United States)

Arrizon, Javier; Morel, Sandrine; Gschaedler, Anne; Monsan, Pierre

2012-04-01

Fructanase and fructosyltransferase are interesting for the tequila process and prebiotics production (functional food industry). In this study, one hundred thirty non-Saccharomyces yeasts isolated from "Mezcal de Oaxaca" were screened for fructanase and fructosyltransferase activity. On solid medium, fifty isolates grew on Agave tequilana fructans (ATF), inulin or levan. In liquid media, inulin and ATF induced fructanase activities of between 0.02 and 0.27U/ml depending of yeast isolate. High fructanase activity on sucrose was observed for Kluyveromyces marxianus and Torulaspora delbrueckii, while the highest fructanase activity on inulin and ATF was observed for Issatchenkia orientalis, Cryptococcus albidus, and Candida apicola. Zygosaccharomyces bisporus and Candida boidinii had a high hydrolytic activity on levan. Sixteen yeasts belonging to K. marxianus, T. delbrueckii and C. apicola species were positive for fructosyltransferase activity. Mezcal microbiota proved to showed to be a source for new fructanase and fructosyltransferases with potential application in the tequila and food industry. Copyright © 2012 Elsevier Ltd. All rights reserved.

Evaluation of soymilk fermentation with a lactic culture

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Martha Cecilia Quicazán

2001-07-01

Full Text Available Soymilk, the protein slurry extracted in water from soybeans, obtained by means of a process tested previously at ICTA (the National University of Colombia's Institute of Food Science and Technology, was fermented by using a thermophyllic lactic culture consisting of L delbrueckii ss. bulgaricus, L. delbrueckii ss. lactis and S. salivarius ss. thermophilus. The soymilk composition was standardised (before fermentation, regarding solids and protein contení, by means of Brix0 as process variable. Soymilk was fermented by applying those same basic operations followed in cow milk fermentation. Acidification was assessed by evaluating pH, titrable acidity and organic acid production during the process by HPLC in an ionic exclusion column. Reologyc property modification was studied and compared with that for cow milk. It was proved that, despite the absence of lactose as substrate, soymilk acidification during this process can be explained by lactic acid production and that soymilk solid content influences acid production and changes in viscosity.

Combining catalytical and biological processes to transform cellulose into high value-added products

Science.gov (United States)

Gavilà, Lorenc; Güell, Edgar J.; Maru, Biniam T.; Medina, Francesc; Constantí, Magda

2017-04-01

Cellulose, the most abundant polymer of biomass, has an enormous potential as a source of chemicals and energy. However, its nature does not facilitate its exploitation in industry. As an entry point, here, two different strategies to hydrolyse cellulose are proposed. A solid and a liquid acid catalysts are tested. As a solid acid catalyst, zirconia and different zirconia-doped materials are proved, meanwhile liquid acid catalyst is carried out by sulfuric acid. Sulfuric acid proved to hydrolyse 78% of cellulose, while zirconia doped with sulfur converted 22% of cellulose. Both hydrolysates were used for fermentation with different microbial strains depending on the desired product: Citrobacter freundii H3 and Lactobacillus delbrueckii, for H2 or lactic acid production respectively. A measure of 2 mol H2/mol of glucose was obtained from the hydrolysate using zirconia with Citrobacter freundii; and Lactobacillus delbrueckii transformed all glucose into optically pure D-lactic acid.

Plant extract enhances the viability of Lactobacillus delbrueckii subsp. bulgaricus and Lactobacillus acidophilus in probiotic nonfat yogurt

Science.gov (United States)

Michael, Minto; Phebus, Randall K; Schmidt, Karen A

2015-01-01

A commercial plant extract (prepared from olive, garlic, onion and citrus extracts with sodium acetate (SA) as a carrier) was evaluated to extend the viability of yogurt starter and probiotic bacteria as a means to enhance the shelf life of live and active culture, probiotic nonfat yogurt. Yogurts prepared from three different formulas (0.5* plant extract, 0.25* SA, or no supplement) and cultures (yogurt starter plus Bifidobacterium animalis,Lactobacillus acidophilus, or both probiotics) were assessed weekly during 29 days of storage at 5°C. Supplemented yogurt mixes had greater buffering capacities than non-supplemented yogurt mixes. At the end of storage, Lactobacillus bulgaricus and L. acidophilus counts in supplemented yogurts were greater compared with non-supplemented yogurts. Supplementation did not affect Streptococcus thermophilus and B. animalis counts. Hence the greater buffering capacity of yogurt containing plant extract could enhance the longevity of the probiotics, L. bulgaricus and L. acidophilus, during storage. PMID:25650127

Plant extract enhances the viability of Lactobacillus delbrueckii subsp. bulgaricus and Lactobacillus acidophilus in probiotic nonfat yogurt.

Science.gov (United States)

Michael, Minto; Phebus, Randall K; Schmidt, Karen A

2015-01-01

A commercial plant extract (prepared from olive, garlic, onion and citrus extracts with sodium acetate (SA) as a carrier) was evaluated to extend the viability of yogurt starter and probiotic bacteria as a means to enhance the shelf life of live and active culture, probiotic nonfat yogurt. Yogurts prepared from three different formulas (0.5* plant extract, 0.25* SA, or no supplement) and cultures (yogurt starter plus Bifidobacterium animalis,Lactobacillus acidophilus, or both probiotics) were assessed weekly during 29 days of storage at 5°C. Supplemented yogurt mixes had greater buffering capacities than non-supplemented yogurt mixes. At the end of storage, Lactobacillus bulgaricus and L. acidophilus counts in supplemented yogurts were greater compared with non-supplemented yogurts. Supplementation did not affect Streptococcus thermophilus and B. animalis counts. Hence the greater buffering capacity of yogurt containing plant extract could enhance the longevity of the probiotics, L. bulgaricus and L. acidophilus, during storage.

Effect of ropy and capsular exopolysaccharides producing strain of ...

African Journals Online (AJOL)

The contribution of selected ropy and capsular Lactobacillus plantarum 162RM on texture of fermented milk as well as on the functionality of kareish cheese was established in this study. The cell suspension of this strain was used in combination with commercial starter cultures MY900 (Lactobacillus delbrueckii ssp.

Transfer of several phytopathogenic Pseudomonas species to Acidovorax as Acidovorax avenae subsp. avenae subsp. nov., comb. nov., Acidovorax avenae subsp. citrulli, Acidovorax avenae subsp. cattleyae, and Acidovorax konjaci.

Science.gov (United States)

Willems, A; Goor, M; Thielemans, S; Gillis, M; Kersters, K; De Ley, J

1992-01-01

DNA-rRNA hybridizations, DNA-DNA hybridizations, polyacrylamide gel electrophoresis of whole-cell proteins, and a numerical analysis of carbon assimilation tests were carried out to determine the relationships among the phylogenetically misnamed phytopathogenic taxa Pseudomonas avenae, Pseudomonas rubrilineans, "Pseudomonas setariae," Pseudomonas cattleyae, Pseudomonas pseudoalcaligenes subsp. citrulli, and Pseudomonas pseudoalcaligenes subsp. konjaci. These organisms are all members of the family Comamonadaceae, within which they constitute a separate rRNA branch. Only P. pseudoalcaligenes subsp. konjaci is situated on the lower part of this rRNA branch; all of the other taxa cluster very closely around the type strain of P. avenae. When they are compared phenotypically, all of the members of this rRNA branch can be differentiated from each other, and they are, as a group, most closely related to the genus Acidovorax. DNA-DNA hybridization experiments showed that these organisms constitute two genotypic groups. We propose that the generically misnamed phytopathogenic Pseudomonas species should be transferred to the genus Acidovorax as Acidovorax avenae and Acidovorax konjaci. Within Acidovorax avenae we distinguished the following three subspecies: Acidovorax avenae subsp. avenae, Acidovorax avenae subsp. cattleyae, and Acidovorax avenae subsp. citrulli. Emended descriptions of the new taxa are presented.

PENGARUH TINGKAT YOGURT DAN WAKTU FERMENTASI TERHADAP KECERNAAN IN VITRO BAHAN KERING, BAHAN ORGANIK, PROTEIN, DAN SERAT KASAR KULIT NANAS FERMENTASI

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Nurhayati (Nurhayati

2014-10-01

Full Text Available Penelitian dilaksanakan untuk melihat pengaruh tingkat yogurt dan waktu fermentasi terhadap kecernaan in vitro bahan kering, bahan organik, protein, dan serat kasar kulit nanas fermentasi. Penelitian dilakukan menggunakan Rancangan Acak Lengkap pola faktorial dengan 2 faktor yaitu tingkat yogurt (0, 3, 6, dan 9 ml/kg dan lama waktu fermentasi (24, 48, dan 72 jam yang diulang sebanyak 5 kali. Bahan yang digunakan adalah kulit nanas, plain yogurt yang mengandung bakteri Lactobacillus delbrueckii subsp. bulgaricus dan Streptococcus salivarius subsp. thermophilus, bahan kimia yang digunakan untuk analisis proksimat protein dan serat kasar kulit nanas fermentasi, larutan saliva buatan McDougall dan cairan rumen. Hasil penelitian menunjukkan perbedaan pengaruh yang nyata (P<0,05 tingkat yogurt terhadap kecernaan in vitro bahan kering, bahan organik, dan protein kasar tetapi tidak berbeda nyata terhadap kecernaan serat kasar. Waktu fermentasi berpengaruh nyata (P<0,05 terhadap kecernaan bahan kering, bahan organik, protein kasar, dan serat kasar secara in vitro. Interaksi tingkat yogurt dengan waktu fermentasi memberikan perbedaan pengaruh yang nyata (P<0,05 terhadap kecernaan bahan kering, bahan organik dan protein kasar tetapi tidak memberikan perbedaan pengaruh nyata terhadap kecernaan serat kasar. Kesimpulan dari penelitian ini bahwa tingkat yogurt 6 ml/kg dan waktu fermentasi 72 jam dapat meningkatkan kecernaan in vitro bahan kering, bahan organik, dan protein kasar serta menurunkan kecernaan in vitro serat kasar kulit nanas fermentasi. (Kata kunci: Fermentasi, Kecernaan in vitro, Kulit nanas, Yogurt

Molecular characterization of Lactobacillus plantarum DMDL 9010, a strain with efficient nitrite degradation capacity.

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Yong-tao Fei

Full Text Available Nitrites commonly found in food, especially in fermented vegetables, are potential carcinogens. Therefore, limiting nitrites in food is critically important for food safety. A Lactobacillus strain (Lactobacillus sp. DMDL 9010 was previously isolated from fermented vegetables by our group, and is not yet fully characterized. A number of phenotypical and genotypical approaches were employed to characterize Lactobacillus sp. DMDL 9010. Its nitrite degradation capacity was compared with four other Lactobacillus strains, including Lactobacillus casei subsp. rhamnosus 719, Lactobacillus delbrueckii subsp. bulgaricu 1.83, Streptococcus thermophilus 1.204, and lactobacillus plantarum 8140, on MRS medium. Compared to these four Lactobacillus strains, Lactobacillus sp. DMDL 9010 had a significantly higher nitrite degradation capacity (P<0.001. Based on 16S rDNA sequencing and sequence comparison, Lactobacillus sp. DMDL 9010 was identified as either Lactobacillus plantarum or Lactobacillus pentosus. To further identify this strain, the flanking regions (922 bp and 806 bp upstream and downstream, respectively of the L-lactate dehydrogenase 1 (L-ldh1 gene were amplified and sequenced. Lactobacillus sp. DMDL 9010 had 98.92 and 76.98% sequence identity in the upstream region with L. plantarum WCFS1 and L. pentosus IG1, respectively, suggesting that Lactobacillu sp. DMDL 9010 is an L. plantarum strain. It was therefore named L. plantarum DMDL 9010. Our study provides a platform for genetic engineering of L. plantarum DMDL 9010, in order to further improve its nitrite degradation capacity.

Probiotic properties of lactic acid bacteria isolated from water-buffalo mozzarella cheese.

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Jeronymo-Ceneviva, Ana Beatriz; de Paula, Aline Teodoro; Silva, Luana Faria; Todorov, Svetoslav Dimitrov; Franco, Bernadette Dora G Mello; Penna, Ana Lúcia B

2014-12-01

This study evaluated the probiotic properties (stability at different pH values and bile salt concentration, auto-aggregation and co-aggregation, survival in the presence of antibiotics and commercial drugs, study of β-galactosidase production, evaluation of the presence of genes encoding MapA and Mub adhesion proteins and EF-Tu elongation factor, and the presence of genes encoding virulence factor) of four LAB strains (Lactobacillus casei SJRP35, Leuconostoc citreum SJRP44, Lactobacillus delbrueckii subsp. bulgaricus SJRP57 and Leuconostoc mesenteroides subsp. mesenteroides SJRP58) which produced antimicrobial substances (antimicrobial peptides). The strains survived the simulated GIT modeled in MRS broth, whole and skim milk. In addition, auto-aggregation and the cell surface hydrophobicity of all strains were high, and various degrees of co-aggregation were observed with indicator strains. All strains presented low resistance to several antibiotics and survived in the presence of commercial drugs. Only the strain SJRP44 did not produce the β-galactosidase enzyme. Moreover, the strain SJRP57 did not show the presence of any genes encoding virulence factors; however, the strain SJRP35 presented vancomycin resistance and adhesion of collagen genes, the strain SJRP44 harbored the ornithine decarboxylase gene and the strain SJRP58 generated positive results for aggregation substance and histidine decarboxylase genes. In conclusion, the strain SJRP57 was considered the best candidate as probiotic cultures for further in vivo studies and functional food products development.

Microbes of fermented kefir-like using combination of kefir grains and Bifidobacterium longum

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Sri Usmiati

2005-03-01

Full Text Available The objectives of research were to find out physico-chemical characters and to detect flavor volatile compound of kefir-like. Material used was skim milk TS 9.5% which was heated at 85oC for 30 minutes and cooled at 22oC before innoculation of the starter. Microorganisms used were (a Lactobacillus acidophilus P155110, (b Lactobacillus delbrueckii subsp. Bulgaricus NCIMB 11778, (c Lactococcus lactis P155610, (d Leuconostoc mesenteroides subsp. dextranicum NCIMB 3350, (e Acetobacter aceti P154810, (f Bifidobacterium longum BF1, and (g Saccharomyces cerevisiae P156252. The treatments consist of P1 = without (b; P2 = without (a; and P3= used (a until (g. The physico-chemical characters identified were lactic acid and lactose percentages, pH, viscosity, organoleptic test for intensity of kefir-like sensory attributes. Results indicated that B. longum was potential bacterium use for starter combination on kefir-like making. The use starter P1 combination has high acidity and viscosity, low pH and lactose percentage, and high intensity on attribute creamy-white color, soft and curdle consistency, and kefir specific aroma on kefir-like. Volatile compound acid group were dominate by high acidity character on kefir-like resulted from starter P1 combination. Compound of 3-hydroxi-2-butanone (acetoin was affecting butter-like of P3 character. This compound resulted from which is a character of fermented milk flavor was not detected on P1 kefir-like.

Some low homogenization pressures improve certain probiotic characteristics of yogurt culture bacteria and Lactobacillus acidophilus LA-K.

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Muramalla, T; Aryana, K J

2011-08-01

Lactobacillus delbrueckii ssp. bulgaricus, Streptococcus salivarius ssp. thermophilus, and Lactobacillus acidophilus are dairy cultures widely used in the manufacture of cultured dairy products. Commonly used homogenization pressures in the dairy industry are 13.80 MPa or less. It is not known whether low homogenization pressures can stimulate bacteria to improve their probiotic characteristics. Objectives were to determine the effect of homogenization at 0, 3.45, 6.90, 10.34, and 13.80 MPa on acid tolerance, bile tolerance, protease activity, and growth of L. delbrueckii ssp. bulgaricus LB-12, S. salivarius ssp. thermophilus ST-M5, and L. acidophilus LA-K. The cultures were individually inoculated in cool autoclaved skim milk (4°C) and homogenized for 5 continuous passes. Growth and bile tolerance of samples were determined hourly for 10h of incubation. Acid tolerance was determined every 20 min for 120 min of incubation. Protease activity was determined at 0, 12, and 24h of incubation. All homogenization pressures studied improved acid tolerance of L. delbrueckii ssp. bulgaricus LB-12 but had no beneficial effect on protease activity and had negative effects on growth and bile tolerance. A pressure of 6.90 MPa improved acid tolerance, bile tolerance, and protease activity of S. salivarius ssp. thermophilus ST-M5, but none of the homogenization pressures studied had an effect on its growth. Homogenization pressures of 13.80 and 6.90 MPa improved acid tolerance and bile tolerance, respectively, of L. acidophilus LA-K but had no effect on protease activity and its growth. Some low homogenization pressures positively influenced some characteristics of yogurt culture bacteria and L. acidophilus LA-K. Culture pretreatment with some low homogenization pressures can be recommended for improvement of certain probiotic characteristics. Copyright © 2011 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Anti-Listeria starters: in vitro selection and production plant evaluation.

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Raimondi, Stefano; Popovic, Mina; Amaretti, Alberto; Di Gioia, Diana; Rossi, Maddalena

2014-05-01

Anti-Listeria bacterial starters are highly demanded by the meat industry. Novel bioprotective anti-Listeria starters were searched among Lactobacillus species strains isolated from artisanal sausages. The screening confirmed that anti-Listeria activity is a strain-specific property and yielded only 1 strain (of 36) exhibiting a satisfactory level of inhibition, L. delbrueckii WC0286. This strain was compared with two commercial bioprotective starters, SafePro B-SF-43 and SafePro B-LC-20, in a model simulating in vitro the first step of the fermentation process. The presence of the bioprotective starters did not modify the pH in such a way that could affect the safety or organoleptic properties of the product. Both SafePro B-SF-43 and SafePro B-LC-20 effected an important reduction of Listeria counts (0.56 and 0.72 log CFU g(-1), respectively, in 72 h), while the anti-Listeria effect of L. delbrueckii WC0286 was minor (0.15 log CFU g(-1)). These results discouraged the utilization of L. delbrueckii WC0286 for a challenge test in a pilot salami production, in favor of the best-performing bioprotective starter, SafePro B-LC-20. The test confirmed that SafePro B-LC-20 did not alter the acidification trend of sausages and was capable of inhibiting Listeria, which decreased by 1.21 log CFU g(-1). This information is relevant to address research activity toward the development of new bioprotective starters. The data herein presented demonstrate that the efficacy in Listeria control of potentially bioprotective bacterial starters requires further validation in real meat matrixes, possibly by using in vitro meat fermentation experiments to narrow down the list of candidates before pilot scale challenge tests.

Evaluation of different lactic acid bacterial strains for probiotic characteristics

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B. Srinu,

2013-08-01

Full Text Available Objective: The objective of the present study was to collect different Lactic acid bacterial strains from culture collection centers and screen their functional probiotic characteristics such as acid tolerance, bile tolerance, antibacterial activity and antibiotic sensitivity for their commercial use. Materials and Methods: Acid and bile tolerence of selected LAB(Lactic acid bacteria was determined. The antibiotic resistance of Lactobacillus species was assessed using different antibiotic discs on de Mann Rogosa Sharpe broth (MRS agar plates seeded with the test probiotic organism. The antibacterial activity of LAB was assessed by using well diffusion method.Results: Among the six probiotic strains tested, all showed good survivability at high bile salt concentration (0.3 to 2.0 % oxgall and good growth at a low pH of 1.5 to 3.5. These probiotic species showed good survival abilities in acidic pH of 2.0 to 3.5 except Lactobacillus delbrueckii subspp. bulgaricus 281 which did not grown at pH of 2.0. Lactobacillus fermentum 141 was able to grow even at pH of 1.5 also. Among the six lactic acid species, Lactobacillus fermentum 141 (except Tetracycline, Lactobacillus delbrueckii subspp. Bulgaricus 281 except (Cefpodoxime and all other LAB were resistant to all the antibiotics tested (Ampicillin, Nalidixic acid , Ciprofloxacin ,Co-Trimoxazole, Gentamicin and Cefpodoxime. All these probiotic organisms were screened for their in vitro inhibition ability against pathogenic microorganisms namely, E.coli ATCC (American type culture collection centre, Pseudomonas aeruginosa, Salmonella paratyphi, Staphylococcus aureus. Lactobacillus delbrueckii subspp. bulgaricus 281, Lactobacillus casei 297 and Lactobacillus fermentum 141 inhibited the growth of all the pathogenic bacteria used in the study. Conclusion: The study indicated Lactobacillus fermentum 141 and Lactobacillus casei 297 as potential functional probiotics for future in vivo studies for

Clustering of Pan- and Core-genome of Lactobacillus provides Novel Evolutionary Insights for Differentiation.

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Inglin, Raffael C; Meile, Leo; Stevens, Marc J A

2018-04-24

Bacterial taxonomy aims to classify bacteria based on true evolutionary events and relies on a polyphasic approach that includes phenotypic, genotypic and chemotaxonomic analyses. Until now, complete genomes are largely ignored in taxonomy. The genus Lactobacillus consists of 173 species and many genomes are available to study taxonomy and evolutionary events. We analyzed and clustered 98 completely sequenced genomes of the genus Lactobacillus and 234 draft genomes of 5 different Lactobacillus species, i.e. L. reuteri, L. delbrueckii, L. plantarum, L. rhamnosus and L. helveticus. The core-genome of the genus Lactobacillus contains 266 genes and the pan-genome 20'800 genes. Clustering of the Lactobacillus pan- and core-genome resulted in two highly similar trees. This shows that evolutionary history is traceable in the core-genome and that clustering of the core-genome is sufficient to explore relationships. Clustering of core- and pan-genomes at species' level resulted in similar trees as well. Detailed analyses of the core-genomes showed that the functional class "genetic information processing" is conserved in the core-genome but that "signaling and cellular processes" is not. The latter class encodes functions that are involved in environmental interactions. Evolution of lactobacilli seems therefore directed by the environment. The type species L. delbrueckii was analyzed in detail and its pan-genome based tree contained two major clades whose members contained different genes yet identical functions. In addition, evidence for horizontal gene transfer between strains of L. delbrueckii, L. plantarum, and L. rhamnosus, and between species of the genus Lactobacillus is presented. Our data provide evidence for evolution of some lactobacilli according to a parapatric-like model for species differentiation. Core-genome trees are useful to detect evolutionary relationships in lactobacilli and might be useful in taxonomic analyses. Lactobacillus' evolution is directed

Survival of Lactobacillus bulgaricus and Bifidobacterium animalis in yoghurts made from commercial starter cultures during refrigerated storage

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Eva Dudriková

2017-01-01

Full Text Available All over the world, fermented dairy products have been consumed for nutrition and maintenance of good health for a very long time. This study evaluated the survival of Lactobacillus delbrueckii ssp. bulgaricus and Bifidobacterium animalis ssp. lactis BB-12 in yoghurts after the manufacturing during the shelf-life up to 21 days at 4 °C, which is mostly accepted by the consumers. The titratable acidity and pH showed the same patterns of increase or decline after manufacturing and storage of yoghurts. There was a significant difference (p <0.05 in acidity between yoghurts in glass bottle and plastic cup. The increase in numbers of lactobacilli and bifidobacteria and their survival during storage time were dependent on the species and strain of associative yoghurt bacteria (control-only yoghurt lactic acid bacteria and experimental containing except yoghurt culture also Bifidobacterium animalis ssp. lactis BB-12 and on the packaging material (glass bottle versus plastic cup. It was observed, that counts of bifidobacteria were lower than counts of Lactobacillus delbrueckii ssp. bulgaricus (190 to 434 x 107 at 1d and slowly increased (p <0.001 at maximum level on day 7 (294.3 - 754 x 107 and then slowly declined to 6.33 x 107 in glass bottle and 2.33 x 107 in plastic cups, respectively. Lactobacillus delbrueckii ssp. bulgaricus multiplied better in glass bottles than in plastic cups, as observed during experimental period in-group with Bifidobacterium animalis ssp. lactis BB-12. At the end of the storage period at 4 ºC, viable counts of lactobacilli were higher (p <0.001 in glass bottles. Al the yoghurts, contained the recommended levels of lactobacilli and bifidobacteria (107 cfu.g-1 at the end of storage period (21 d. 

Molecular quantification of lactic acid bacteria in fermented milk products using real-time quantitative PCR.

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Furet, Jean-Pierre; Quénée, Pascal; Tailliez, Patrick

2004-12-15

Real-time quantitative PCR assays were developed for the absolute quantification of lactic acid bacteria (LAB) (Streptococcus thermophilus, Lactobacillus delbrueckii, L. casei, L. paracasei, L. rhamnosus, L. acidophilus and L. johnsonii) in fermented milk products. The results of molecular quantification and classic bacterial enumeration did not differ significantly with respect to S. thermophilus and the species of the L. casei group which were detected in the six commercial fermented products tested, thus showing that DNA extraction was efficient and that genomic DNA solutions were free of PCR inhibitors. For L. delbrueckii, the results of bacterial enumeration were generally lower by a factor 10 to 100 than those of PCR quantification, suggesting a loss of viability during storage of the dairy products at 1-8 degrees C for most of the strains in this species. Real-time quantitative assays enabled identification of the species of lactic acid bacterial strains initially present in commercial fermented milk products and their accurate quantification with a detection threshold of 10(3) cells per ml of product.

New oenological practice to promote non-Saccharomyces species of interest: saturating grape juice with carbon dioxide.

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Chasseriaud, Laura; Coulon, Joana; Marullo, Philippe; Albertin, Warren; Bely, Marina

2018-04-01

Non-Saccharomyces yeast species, naturally found in grape must, may impact wine quality positively or negatively. In this study, a mixture of five non-Saccharomyces species (Torulaspora delbrueckii, Metschnikowia spp., Starmerella bacillaris (formerly called Candida zemplinina), Hanseniaspora uvarum, Pichia kluyveri), mimicking the composition of the natural non-Saccharomyces community found in grape must, was used for alcoholic fermentation. The impact of CO 2 saturation of the grape juice was studied first on this mixture alone, and then in the presence of Saccharomyces cerevisiae. Two isogenic strains of this species were used: the first with a short and the second a long fermentation lag phase. This study demonstrated that saturating grape juice with CO 2 had interesting potential as an oenological technique, inhibiting undesirable species (S. bacillaris and H. uvarum) and stimulating non-Saccharomyces of interest (T. delbrueckii and P. kluyveri). This stimulating effect was particularly marked when CO 2 saturation was associated with the presence of S. cerevisiae with long fermentation lag phase. The direct consequence of this association was an enhancement of 3-SH levels in the resulting wine.

Hydrogen production by co-cultures of Lactobacillus and a photosynthetic bacterium, Rhodobacter sphaeroides RV

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Asada, Yasuo; Ishimi, Katsuhiro [Department of General Education, College of Science and Technology, Nihon University, Narashinodai, Chiba 274-8501 (Japan); Tokumoto, Masaru; Aihara, Yasuyuki; Oku, Masayo; Kohno, Hideki [Department of Applied Molecular Chemistry, College of Industrial Technology, Nihon University, Izumi-cho, Chiba 275-8575 (Japan); Wakayama, Tatsuki; Miyake, Jun [Research Institute for Cell Engineering, National Institute of Advanced Industrial Science and Technology, Nakoji, Amagasaki, Hyogo 661-0974 (Japan); Tomiyama, Masamitsu [Genetic Diversity Department, National Institute of Agrobiological Science, Tsukuba, Ibaraki 305-8602 (Japan)

2006-09-15

Hydrogen production with glucose by using co-immobilized cultures of a lactic acid bacterium, Lactobacillus delbrueckii NBRC13953, and a photosynthetic bacterium, Rhodobacter sphaeroides RV, in agar gels was studied. Glucose was converted to hydrogen gas in a yield of 7.1mol of hydrogen per mole of glucose at a maximum under illuminated conditions. (author)

Improvement of the Texture of Yogurt by Use of Exopolysaccharide Producing Lactic Acid Bacteria.

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Han, Xue; Yang, Zhe; Jing, Xueping; Yu, Peng; Zhang, Yingchun; Yi, Huaxi; Zhang, Lanwei

2016-01-01

19 Streptococcus thermophilus with high exopolysaccharide production were isolated from traditional Chinese fermented dairy products. The exopolysaccharide and viscosity of milk fermented by these 19 isolates were assayed. The strains of Streptococcus thermophilus zlw TM11 were selected because its fermented milk had the highest exopolysaccharide content (380 mg/L) and viscosity (7716 mpa/s). Then Streptococcus thermophilus zlw TM11 was combined with Lactobacillus delbrueckii subsp. bulgaricus 3 4.5 and the combination was named SH-1. The quality of the yogurt fermented by SH-1 and two commercial starter cultures (YO-MIX 465, YF-L711) were compared. It was shown that the exopolysaccharide content of yogurt fermented by SH-1 was similar to that of yogurt fermented by YF-L711 and significantly higher than YO-MIX 465 (p yogurt fermented by SH-1 had the lowest syneresis (8.5%) and better texture and sensory than the samples fermented by YO-MIX 465 and YF-L711. It manifested that the selected higher exopolysaccharide production starter SH-1 could be used as yogurt starter and reduce the amount of adding stabilizer, which can compare with the imported commercial starter culture.

Effect of physical properties on the stability of Lactobacillus bulgaricus in a freeze-dried galacto-oligosaccharides matrix.

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Tymczyszyn, E Elizabeth; Sosa, Natalia; Gerbino, Esteban; Hugo, Ayelen; Gómez-Zavaglia, Andrea; Schebor, Carolina

2012-04-16

The ability of galacto-oligosaccharides (GOS) to protect Lactobacillus delbrueckii subsp. bulgaricus upon freeze drying was analyzed on the basis of their capacity to form glassy structures. Glass transition temperatures (T(g)) of a GOS matrix at various relative humidities (RH) were determined by DSC. Survival of L. bulgaricus in a glassy GOS matrix was investigated after freezing, freeze drying, equilibration at different RHs and storage at different temperatures. At 32 °C, a drastic viability loss was observed. At 20 °C, the survival was affected by the water content, having the samples stored at lower RHs, the highest survival percentages. At 4°C, no decay in the cells count was observed after 45 days of storage. The correlation between molecular mobility [as measured by Proton nuclear magnetic resonance (¹H NMR)] and loss of viability explained the efficiency of GOS as cryoprotectants. The preservation of microorganisms was improved at low molecular mobility and this condition was obtained at low water contents and low storage temperatures. These results are important in the developing of new functional foods containing pre and probiotics. Copyright © 2012 Elsevier B.V. All rights reserved.

Improvement of the Texture of Yogurt by Use of Exopolysaccharide Producing Lactic Acid Bacteria

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Han, Xue; Yang, Zhe; Jing, Xueping; Yu, Peng; Zhang, Yingchun

2016-01-01

19 Streptococcus thermophilus with high exopolysaccharide production were isolated from traditional Chinese fermented dairy products. The exopolysaccharide and viscosity of milk fermented by these 19 isolates were assayed. The strains of Streptococcus thermophilus zlw TM11 were selected because its fermented milk had the highest exopolysaccharide content (380 mg/L) and viscosity (7716 mpa/s). Then Streptococcus thermophilus zlw TM11 was combined with Lactobacillus delbrueckii subsp. bulgaricus 3 4.5 and the combination was named SH-1. The quality of the yogurt fermented by SH-1 and two commercial starter cultures (YO-MIX 465, YF-L711) were compared. It was shown that the exopolysaccharide content of yogurt fermented by SH-1 was similar to that of yogurt fermented by YF-L711 and significantly higher than YO-MIX 465 (p yogurt fermented by SH-1 had the lowest syneresis (8.5%) and better texture and sensory than the samples fermented by YO-MIX 465 and YF-L711. It manifested that the selected higher exopolysaccharide production starter SH-1 could be used as yogurt starter and reduce the amount of adding stabilizer, which can compare with the imported commercial starter culture. PMID:27294135

Dominant lactic acid bacteria in artisanal Pirot cheeses of different ripening period

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Terzić-Vidojević Amarela

2009-01-01

Full Text Available In this study two raw cow's milk cheeses of a different ripening period were examined. The cheeses were taken from a country household in the region of mountain Stara Planina and manufactured without adding of starter culture. A total 106 lactic acid bacteria (LAB strains were isolated from both cheeses. They are tested by classical physiological tests as well as by API 50 CH tests. Proteolytic and antimicrobial activities were done too. Identification of LAB isolates was done by repetitive extragenic palindromic-polimerase chain reaction (rep-PCR with (GTG5 primer. The LAB isolates from cheese BGPT9 (four days old belonged to the eight species of LAB (Lactobacillus plantarum, Lactobacillus paracasei subsp. paracasei, Lactobacillus delbrueckii, Lactobacillus brevis, Enterococcus faecium, Enterococcus faecalis, Enterococcus durans and Leuconostoc garlicum, while in the BGPT10 cheese (eight months old only two species were present (Lactobacillus plantarum and Enterococcus faecium. Proteolytic activity showed 30 LAB from BGPT9 cheese, mainly enterococci. From BGPT10 cheese only one isolate (which belonged to the Lactobacillus plantarum species possessed partial ability to hydrolyze β-casein. Seven enterococci from BGPT9 cheese and four enterococci from BGPT10 cheese produced antimicrobial compounds.

Role of viability of probiotic strains in their persistence in the gut and in mucosal immune stimulation.

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Galdeano, C Maldonado; Perdigón, G

2004-01-01

To determine how probiotic bacteria contact with intestinal epithelial and immune cells and the conditions to induce a good mucosal immune stimulation. Lactobacillus casei was studied by transmission electron microscopy (TEM) to determine its interaction with the gut. We compared the influence of viable and nonviable lactic acid bacteria on the intestinal mucosal immune system (IMIS) and their persistence in the gut of mice. TEM showed whole Lact. casei adhered to the villi; the bacterial antigen was found in the cytoplasm of the enterocytes. Viable bacteria stimulated the IMIS to a greater extent than nonviable bacteria with the exception of Lact. delbrueckii subsp. bulgaricus. For all the strains assayed at 72 h no antigenic particles were found in the intestine. Antigenic particles but not the whole bacteria can enter to epithelial cells and contact with the immune cells. Bacterial viability is a condition for a better stimulation of the IMIS. We demonstrated that only antigenic particle interact with the immune cells and their fast clearance from the gut agrees with those described for the particulate antigens. The regular consumption of probiotics should not adversely affect the host.

Microbial community dynamics in thermophilic undefined milk starter cultures.

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Parente, Eugenio; Guidone, Angela; Matera, Attilio; De Filippis, Francesca; Mauriello, Gianluigi; Ricciardi, Annamaria

2016-01-18

Model undefined thermophilic starter cultures were produced from raw milk of nine pasta-filata cheesemaking plants using a selective procedure based on pasteurization and incubation at high temperature with the objective of studying the microbial community dynamics and the variability in performances under repeated (7-13) reproduction cycles with backslopping. The traditional culture-dependent approach, based on random isolation and molecular characterization of isolates was coupled to the determination of pH and the evaluation of the ability to produce acid and fermentation metabolites. Moreover, a culture-independent approach based on amplicon-targeted next-generation sequencing was employed. The microbial diversity was evaluated by 16S rRNA gene sequencing (V1-V3 regions), while the microdiversity of Streptococcus thermophilus populations was explored by using novel approach based on sequencing of partial amplicons of the phosphoserine phosphatase gene (serB). In addition, the occurrence of bacteriophages was evaluated by qPCR and by multiplex PCR. Although it was relatively easy to select for a community dominated by thermophilic lactic acid bacteria (LAB) within a single reproduction cycle, final pH, LAB populations and acid production activity fluctuated over reproduction cycles. Both culture-dependent and -independent methods showed that the cultures were dominated by either S. thermophilus or Lactobacillus delbrueckii subsp. lactis or by both species. Nevertheless, subdominant mesophilic species, including lactococci and spoilage organisms, persisted at low levels. A limited number of serB sequence types (ST) were present in S. thermophilus populations. L. delbrueckii and Lactococcus lactis bacteriophages were below the detection limit of the method used and high titres of cos type S. thermophilus bacteriophages were detected in only two cases. In one case a high titre of bacteriophages was concurrent with a S. thermophilus biotype shift in the culture

Persistence of Escherichia coli O157:H7 in dairy fermentation systems.

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Dineen, S S; Takeuchi, K; Soudah, J E; Boor, K J

1998-12-01

We examined (i) the persistence of Escherichia coli O157:H7 as a postpasteurization contaminant in fermented dairy products; (ii) the ability of E. coli O157:H7 strains with and without the general stress regulatory protein, RpoS, to compete with commercial starter cultures in fermentation systems; and (iii) the survival of E. coli O157:H7 in the yogurt production process. In commercial products inoculated with 10(3) CFU/ml, E. coli O157:H7 was recovered for up to 12 days in yogurt (pH 4.0), 28 days in sour cream (pH 4.3), and at levels > 10(2) CFU/ml at 35 days in buttermilk (pH 4.1). For the starter culture competition trials, the relative inhibition of E. coli O157:H7 in the experimental fermentation systems was, in decreasing order, thermophilic culture mixture, Lactobacillus delbrueckii subsp. bulgaricus R110 alone, Lactococcus lactis subsp. lactis D280 alone, Lactococcus lactis subsp. cremoris D62 alone, and Streptococcus thermophilus C90 alone showing the least inhibition. Recovery of the rpoS mutant was lower than recovery of its wild-type parent by 72 h or earlier in the presence of individual starter cultures. No E. coli O157:H7 were recovered after the curd formation step in yogurt manufactured with milk inoculated with 10(5) CFU/ml. Our results show that (i) postprocessing entry of E. coli O157:H7 into fermented dairy products represents a potential health hazard; (ii) commercial starter cultures differ in their ability to reduce E. coli O157:H7 CFU numbers in fermentation systems; and (iii) the RpoS protein appears to most effectively contribute to bacterial survival in the presence of conditions that are moderately lethal to the cell.

Screening of probiotic activities of forty-seven strains of Lactobacillus spp. by in vitro techniques and evaluation of the colonization ability of five selected strains in humans.

Science.gov (United States)

Jacobsen, C N; Rosenfeldt Nielsen, V; Hayford, A E; Møller, P L; Michaelsen, K F; Paerregaard, A; Sandström, B; Tvede, M; Jakobsen, M

1999-11-01

The probiotic potential of 47 selected strains of Lactobacillus spp. was investigated. The strains were examined for resistance to pH 2.5 and 0.3% oxgall, adhesion to Caco-2 cells, and antimicrobial activities against enteric pathogenic bacteria in model systems. From the results obtained in vitro, five strains, Lactobacillus rhamnosus 19070-2, L. reuteri DSM 12246, L. rhamnosus LGG, L. delbrueckii subsp. lactis CHCC 2329, and L. casei subsp. alactus CHCC 3137, were selected for in vivo studies. The daily consumption by 12 healthy volunteers of two doses of 10(10) freeze-dried bacteria of the selected strains for 18 days was followed by a washout period of 17 days. Fecal samples were taken at days 0 and 18 and during the washout period at days 5 and 11. Lactobacillus isolates were initially identified by API 50CHL and internal transcribed spacer PCR, and their identities were confirmed by restriction enzyme analysis in combination with pulsed-field gel electrophoresis. Among the tested strains, L. rhamnosus 19070-2, L. reuteri DSM 12246, and L. rhamnosus LGG were identified most frequently in fecal samples; they were found in 10, 8, and 7 of the 12 samples tested during the intervention period, respectively, whereas reisolations were less frequent in the washout period. The bacteria were reisolated in concentrations from 10(5) to 10(8) cells/g of feces. Survival and reisolation of the bacteria in vivo appeared to be linked to pH tolerance, adhesion, and antimicrobial properties in vitro.

Effects of copper supplement on growth and viability of strains used as starters and adjunct cultures for Emmental cheese manufacture.

Science.gov (United States)

Rodríguez, L Mato; Alatossava, T

2008-10-01

To determine the effects of supplemented copper (Cu2+) on growth and viability of strains used as starters and adjunct cultures for Emmental cheese manufacture. Thirteen strains belonging to Lactobacillus delbrueckii, Lactobacillus helveticus, Lactobacillus rhamnosus, Streptococcus thermophilus or Propionibacterium freudenreichii species were exposed to various copper concentrations in the proper growth medium at relevant growth temperatures, and the effects of supplemented copper on bacterial growth and cell viability were determined by optical density and pH measurements, also by platings. Among the species considered, L. delbrueckii was the most copper resistant and S. thermophilus the most sensitive to copper. Anaerobic conditions increased this sensitivity significantly. There was also a considerable amount of variation in copper resistance at strain level. Copper resistance is both a species- and strain-dependent property and may reflect variability in copper-binding capacities by cell wall components among species and strains. In addition, the chemical state of copper may be involved. This study revealed that copper resistance is a highly variable property among starter and adjunct strains, and this variability should be considered when strains are selected for Emmental cheese manufacture.

Pyrosequencing analysis of the microbial diversity of airag, khoormog and tarag, traditional fermented dairy products of mongolia.

Science.gov (United States)

Oki, Kaihei; Dugersuren, Jamyan; Demberel, Shirchin; Watanabe, Koichi

2014-01-01

Here, we used pyrosequencing to obtain a detailed analysis of the microbial diversities of traditional fermented dairy products of Mongolia. From 22 Airag (fermented mare's milk), 5 Khoormog (fermented camel's milk) and 26 Tarag (fermented milk of cows, goats and yaks) samples collected in the Mongolian provinces of Arhangai, Bulgan, Dundgobi, Tov, Uburhangai and Umnugobi, we obtained a total of 81 operational taxonomic units, which were assigned to 15 families, 21 genera and 41 species in 3 phyla. The genus Lactobacillus is a core bacterial component of Mongolian fermented milks, and Lactobacillus helveticus, Lactobacillus kefiranofaciens and Lactobacillus delbrueckii were the predominant species of lactic acid bacteria (LAB) in the Airag, Khoormog and Tarag samples, respectively. By using this pyrosequencing approach, we successfully detected most LAB species that have been isolated as well as seven LAB species that have not been found in our previous culture-based study. A subsequent analysis of the principal components of the samples revealed that L. delbrueckii, L. helveticus, L. kefiranofaciens and Streptococcus thermophilus were the main factors influencing the microbial diversity of these Mongolian traditional fermented dairy products and that this diversity correlated with the animal species from which the milk was sourced.

Acidovorax avenae subsp. avenae

African Journals Online (AJOL)

Jane

2011-06-24

Jun 24, 2011 ... Studies on Acidovorax avenae subsp. avenae, associated with red stripe disease of sugarcane was ... fiber, organic fertilizer and many by-products/co-products with ... colour, colony diameter and size of bacteria (µm) (Dye and Kemp, ..... leaf blight of turmeric caused by Acidovorax avenae subsp. avenae in.

Streptococcus Thermophilus ve Lactobacillus Delbrueckii Subsp. Bulgaricus Virülent Fajlarının Morfolojik Karakterizasyonu (İngilizce

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Esra Acar Soykut

2015-02-01

Full Text Available Bu çalışmada 25 adet S. thermophilus ve 25 adet L. bulgaricus fajının elektron mikroskobik incelemesi yapılarak morfolojik karakterizasyonu gerçekleştirilmiştir. S. thermophilus fajlarında izometrik, hegzagonal baş çapının 53-74 nm, kontraktil olmayan kuyruk uzunluğunun 182-290 nm ve kuyruk genişliğinin de 7-14 nm arasında değiştiği görülmüştür. Bu fajlarda yaka, kuyruk plağı ve fibril benzeri yapıya rastlanmamıştır. İncelenen tüm fajlar, elde edilen verilere dayanılarak diğer S. thermophilus fajları gibi Ackermann sınıflaması Siphoviridae familyasına ve/veya Bradley sınıflaması B grubuna dâhil edilmiştir. S. thermophilus fajlarında olduğu gibi Lb. bulgaricus fajlarında da izometrik, hegzagonal kapsit ve kontraktil olmayan kuyruk yapısı belirlenmiştir. Kapsit çapları 47-73 nm arasında değişirken, kontraktil olmayan kuyruk uzunlukları 117-162 nm ve kuyruk enleri 7-13 nm arasında bulunmuştur. Ackermann sınıflaması Siphoviridae familyasına ve/veya Bradley sınıflaması B grubuna dâhil edilen bu fajlarda yaka, kuyruk tablası ve fibril yapısının varlığı dikkat çekmiştir. S. thermophilus ve L. bulgaricus faj örneklerinin hazırlanmasındaki farklılıkların ve kullanılan elektron mikroskop tiplerinin kuyruk yapılarının görünebilirliğini etkilediği düşünülmüştür.

Lactococcus lactis subsp. tructae subsp. nov. isolated from the intestinal mucus of brown trout (Salmo trutta) and rainbow trout (Oncorhynchus mykiss).

Science.gov (United States)

Pérez, Tania; Balcázar, José Luis; Peix, Alvaro; Valverde, Angel; Velázquez, Encarna; de Blas, Ignacio; Ruiz-Zarzuela, Imanol

2011-08-01

The species Lactococcus lactis currently includes three subspecies; L. lactis subsp. lactis and L. lactis subsp. cremoris, isolated from milk sources, and L. lactis subsp. hordniae, isolated from the leafhopper Hordnia circellata. In this study, three strains, designated L105(T), I3 and L101, were isolated from the intestinal mucus of brown trout (Salmo trutta) and rainbow trout (Oncorhynchus mykiss). These strains were closely related to members of the species Lactococcus lactis. Strain L105(T) showed 99.4 % 16S rRNA gene sequence similarity to that of the type strains L. lactis subsp. lactis NCDO 604(T) and L. lactis subsp. hordniae NCDO 2181(T) and showed 99.9 % similarity to the type strain Lactococcus lactis subsp. cremoris NCDO 607(T). Analysis of two housekeeping genes, rpoB and recA, confirmed the close relationship between the novel strains and L. lactis subsp. cremoris with similarities of 99.3 and 99.7 %, respectively. The three strains could, however, be differentiated from their closest relatives on the basis of several phenotypic characteristics, as was the case for L. lactis subsp. lactis and L. lactis subsp. hordniae, which were also closely related on the basis of 16S rRNA, rpoB and recA gene sequence similarities. The strains isolated in this study represent a new subspecies, for which the name Lactococcus lactis subsp. tructae subsp. nov. is proposed. The type strain is L105(T) ( = LMG 24662(T)  = DSM 21502(T)).

Microbiological characterization of traditional dough fermentation starter (Jiaozi) for steamed bread making by culture-dependent and culture-independent methods.

Science.gov (United States)

Li, Zhijian; Li, Haifeng; Bian, Ke

2016-10-03

In this study, the microbial composition of two types of Jiaozi (a dough fermentation starter in making steamed bread) was investigated using both culture-dependent and culture-independent (PCR-DGGE) methods. The numbers of the cultivable bacteria on MRS at 30°C and yeast on YPD at 28°C in the maize flour Jiaozi (MFJ) were 9.21±0.16 Log CFU/g and 9.18±0.05 Log CFU/g, respectively, which were higher than that in the rice flour Jiaozi (RFJ) (Pyeasts were isolated and identified on the basis of the sequences of their 16S rRNA gene and ITS region. The culture-dependent method showed that Acetobacter tropicalis and Enterococcus durans were the predominant bacteria strains in MFJ, and accounted for 45.7% and 25.7% of the bacteria, and Lactobacillus plantarum and Pediococcus pentosaceus represented 12.8% and 8.6%. In the RFJ sample, the most prominent isolate was P. pentosaceus (38.6%), followed by L. plantarum (24.3%), A. tropicalis (22.8%), and E. durans (5.7%). P. pentosaceus and L. plantarum were also detected in both starters by PCR-DGGE, while some bacteria species such as A. tropicalis and E. durans, recovered as pure cultures, were not detected by direct PCR-DGGE. On the other hand, Lactobacillus brevis, Weissella sp. and Lactobacillus alimentarius detected by PCR-DGGE were not recovered in any of the media and conditions used. In the MFJ sample, the isolated main yeast species were identified as Wickerhamomyces anomalus (67.2%), Saccharomyces cerevisiae (27.9%) and Torulaspora delbrueckii (4.9%). In addition to S. cerevisiae (42.9%), W. anomalus (27.0%) and T. delbrueckii (7.9%), Saccharomycopsis fibuligera was also identified as the predominant isolate in RFJ samples and accounted for 22.2%. PCR-DGGE also indicated the presence of W. anomalus and S. cerevisiae in both MFJ and RFJ starters and S. fibuligera was also detected in RFJ, but T. delbrueckii was not detected in both samples. Copyright © 2016 Elsevier B.V. All rights reserved.

[Identification of lactic acid bacteria in commercial yogurt and their antibiotic resistance].

Science.gov (United States)

Qin, Yuxuan; Li, Jing; Wang, Qiuya; Gao, Kexin; Zhu, Baoli; Lv, Na

2013-08-04

To identify lactic acid bacteria (LAB) in commercial yogurts and investigate their antibiotic resistance. LABs were cultured from 5 yogurt brands and the isolates were identified at the species level by 16S rRNA sequence. Genotyping was performed by repetitive extragenic palindromic PCR (rep-PCR). The sensitivity to 7 antibiotics was tested for all LAB isolates by Kirby-Bauer paper diffusion (K-B method). Meanwhile, 9 antibiotic resistance genes (ARGs), including erythromycin resistance genes (ermA and ermB) and tetracycline resistance genes (tetM, tetK, tetS, tetQ, tetO, tetL and tetW), were detected by PCR amplification in the identified LAB isolates. The PCR products were confirmed by sequencing. Total 100 LABs were isolated, including 23 Lactobacillus delbrueckii ssp. bulgaricus, 26 Lactobacillus casei, 30 Streptococcus thermophilus, 5 Lactobacillus acidophilus, 6 Lactobacillus plantarum, and 10 Lactobacillus paracasei. The drug susceptibility test shows that all 100 isolates were resistant to gentamicin and streptomycin, 42 isolates were resistant to vancomycin, and on the contrary all were sensitive to cefalexin, erythromycin, tetracycline and oxytetracycline. Moreover, 5 ARGs were found in the 28 sequencing confirmed isolates, ermB gene was detected in 8 isolates, tet K in 4 isolates, tetL in 2 isolates, tetM in 4 isolates, tetO in 2 isolates. erm A, tet S, tet Q and tet W genes were not detected in the isolates. Antibiotic resistance genes were found in 53.57% (15/28) sequenced isolates, 2 -3 antibiotic resistance genes were detected in 4 isolates of L. delbrueckii ssp. bulgaricus. Some LABs were not labeled in commercial yogurt products. Antibiotic resistance genes tend to be found in the starter culture of L. delbrueckii ssp. Bulgaricus and S. thermophilus. All the LAB isolates were sensitive to erythromycin and tetracycline, even though some carried erythromycin and/or tetracycline resistance genes. We proved again that LAB could carry antibiotic

Defining the bacteroides ribosomal binding site.

Science.gov (United States)

Wegmann, Udo; Horn, Nikki; Carding, Simon R

2013-03-01

The human gastrointestinal tract, in particular the colon, hosts a vast number of commensal microorganisms. Representatives of the genus Bacteroides are among the most abundant bacterial species in the human colon. Bacteroidetes diverged from the common line of eubacterial descent before other eubacterial groups. As a result, they employ unique transcription initiation signals and, because of this uniqueness, they require specific genetic tools. Although some tools exist, they are not optimal for studying the roles and functions of these bacteria in the human gastrointestinal tract. Focusing on translation initiation signals in Bacteroides, we created a series of expression vectors allowing for different levels of protein expression in this genus, and we describe the use of pepI from Lactobacillus delbrueckii subsp. lactis as a novel reporter gene for Bacteroides. Furthermore, we report the identification of the 3' end of the 16S rRNA of Bacteroides ovatus and analyze in detail its ribosomal binding site, thus defining a core region necessary for efficient translation, which we have incorporated into the design of our expression vectors. Based on the sequence logo information from the 5' untranslated region of other Bacteroidales ribosomal protein genes, we conclude that our findings are relevant to all members of this order.

Improvement of the Texture of Yogurt by Use of Exopolysaccharide Producing Lactic Acid Bacteria

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Xue Han

2016-01-01

Full Text Available 19 Streptococcus thermophilus with high exopolysaccharide production were isolated from traditional Chinese fermented dairy products. The exopolysaccharide and viscosity of milk fermented by these 19 isolates were assayed. The strains of Streptococcus thermophilus zlw TM11 were selected because its fermented milk had the highest exopolysaccharide content (380 mg/L and viscosity (7716 mpa/s. Then Streptococcus thermophilus zlw TM11 was combined with Lactobacillus delbrueckii subsp. bulgaricus 3 4.5 and the combination was named SH-1. The quality of the yogurt fermented by SH-1 and two commercial starter cultures (YO-MIX 465, YF-L711 were compared. It was shown that the exopolysaccharide content of yogurt fermented by SH-1 was similar to that of yogurt fermented by YF-L711 and significantly higher than YO-MIX 465 (p<0.05. In addition, the yogurt fermented by SH-1 had the lowest syneresis (8.5% and better texture and sensory than the samples fermented by YO-MIX 465 and YF-L711. It manifested that the selected higher exopolysaccharide production starter SH-1 could be used as yogurt starter and reduce the amount of adding stabilizer, which can compare with the imported commercial starter culture.

Immunobiotic Lactobacillus strains augment NLRP3 expression in newborn and adult porcine gut-associated lymphoid tissues.

Science.gov (United States)

Tohno, Masanori; Shimosato, Takeshi; Aso, Hisashi; Kitazawa, Haruki

2011-12-15

We isolated cDNA encoding porcine nucleotide-binding domain-like receptor family, pryin domain containing 3 (NLRP3) from Peyer's patches. The complete nucleotide open reading frame of porcine NLRP3 contains 3108-bp encoding a deduced polypeptide of 1036-amino acid residues. The porcine NLRP3 amino acid sequence is more similar to the longest isoform of human than the mouse counterpart. The predicted amino acid sequence of porcine NLRP3 presented nine C-terminal leucine-rich repeat domains. In newborn swine, the expression of NLRP3 was detected at higher levels in spleen and mesenteric lymph nodes, while lower levels were observed in intestinal tissues. In adult swine, NLRP3 was strongly expressed in Peyer's patches and the mesenteric lymph nodes, and the expression level in the lower intestinal tissues was comparable to that in spleen. Toll-like receptor and nucleotide-binding domain ligands, as well as Lactobacillus delbrueckii subsp. bulgaricus and Lactobacillus gasseri, enhanced NLRP3 expression in gut-associated lymphoid tissues (GALT) of newborn and adult swine. Our results should aid in understanding the intestinal immunoregulatory mechanisms underlying NLRP3 activation and the priming ability of immunobiotic lactic acid bacteria in porcine GALT. Copyright © 2011 Elsevier B.V. All rights reserved.

The potential of species-specific tagatose-6-phosphate (T6P) pathway in Lactobacillus casei group for galactose reduction in fermented dairy foods.

Science.gov (United States)

Wu, Qinglong; Shah, Nagendra P

2017-04-01

Residual lactose and galactose in fermented dairy foods leads to several industrial and health concerns. There is very little information pertaining to manufacture of fermented dairy foods that are low in lactose and galactose. In the present study, comparative genomic survey demonstrated the constant presence of chromosome-encoded tagatose-6-phosphate (T6P) pathway in Lactobacillus casei group. Lactose/galactose utilization tests and β-galactosidase assay suggest that PTS Gal system, PTS Lac system and T6P pathway are major contributors for lactose/galactose catabolism in this group of organisms. In addition, it was found than lactose catabolism by Lb. casei group accumulated very limited galactose in the MRS-lactose medium and in reconstituted skim milk, whereas Streptococcus thermophilus and Lb. delbrueckii subsp. bulgaricus (Lb. bulgaricus) strains secreted high amount of galactose extracellularly. Moreover, co-culturing Lb. casei group with Str. thermophilus showed significant reduction in galactose content, while co-culturing Lb. casei group with Lb. bulgaricus showed significant reduction in lactose content but significant increase in galactose content in milk. Overall, the present study highlighted the potential of Lb. casei group for reducing galactose accumulation in fermented milks due to its species-specific T6P pathway. Copyright © 2016 Elsevier Ltd. All rights reserved.

Novel Method of Lactic Acid Production by Electrodialysis Fermentation

OpenAIRE

Hongo, Motoyoshi; Nomura, Yoshiyuki; Iwahara, Masayoshi

1986-01-01

In lactic acid fermentation by Lactobacillus delbrueckii, the produced lactic acid affected the lactic acid productivity. Therefore, for the purpose of alleviating this inhibitory effect, an electrodialysis fermentation method which can continuously remove produced lactic acid from the fermentation broth was applied to this fermentation process. As a result, the continuation of fermentation activity was obtained, and the productivity was three times higher than in non-pH-controlled fermentati...

Biochemical Characteristics and Viability of Probiotic and Yogurt Bacteria in Yogurt during the Fermentation and Refrigerated Storage

OpenAIRE

F Sarvari; A.M. Mortazavian; M.R. Fazei

2014-01-01

This research aimed to investigate the viability of probiotic bacteria (Lactobacillus acidophilus LA-5 and Bifidobacterium lactis BB-12) and yogurt bacteria (Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus) in yogurt during the fermentation, immediately after fermentation and during refrigerated storage (21 d, 4˚C). Also the biochemical characteristics of milk as affected by the commercial 4-strain mixed starter culture were investigated. Storage time affected the via...

Iogurte probiótico produzido com leite de cabra suplementado com Bifidobacterium spp

Directory of Open Access Journals (Sweden)

V Mazochi

2010-12-01

Full Text Available Avaliaram-se iogurtes de leite de cabra contendo ou não Bifidobacterium longum, B. breve, B. pseudolongum ou B. bifidum, adicionados ou não de aroma de morango. Os dados obtidos nas análises higiênico-sanitárias e físico-químicas foram dentro dos valores exigidos pela legislação brasileira; apenas o valor encontrado para lactose esteve abaixo do recomendado. Quanto às bactérias do iogurte, não houve diferença na contagem de Streptococcus salivarius subsp. thermophilus durante a estocagem, e não foi detectado Lactobacillus delbrueckii subsp. bulgaricus nas diluições utilizadas. A enumeração de Bifidobacterium spp. manteve-se entre 10(6 e 10(8UFC/mL e não diferiu entre as espécies ao longo do tempo. Considerando-se a adição ou não de aroma, a análise das variáveis tempo e aroma não mostrou diferença estatística. A contagem entre os Bifidobacterium spp. demonstrou que nenhum microrganismo apresentou um comportamento superior a outro. Na análise sensorial, as amostras de iogurtes adicionados ou não de Bifidobacterium spp. e adicionados de aroma de morango não apresentaram diferenças entre si. O estudo mostrou ser possível a elaboração de iogurte de leite de cabra adicionado de Bifidobacterium spp. e de aroma de morango com qualidade assegurada, potencial para uso probiótico e boa aceitação pelo consumidor.

Prevalence of Streptococcus dysgalactiae subsp. equisimilis and S. equi subsp. zooepidemicus in a sample of healthy dogs, cats and horses.

Science.gov (United States)

Acke, E; Midwinter, A C; Lawrence, K; Gordon, S J G; Moore, S; Rasiah, I; Steward, K; French, N; Waller, A

2015-09-01

To estimate the prevalence of β-haemolytic Lancefield group C streptococci in healthy dogs, cats and horses; to determine if frequent contact with horses was associated with isolation of these species from dogs and cats; and to characterise recovered S. equi subsp. zooepidemicus isolates by multilocus sequence typing. Oropharyngeal swabs were collected from 197 dogs and 72 cats, and nasopharyngeal swabs from 93 horses. Sampling was carried out at the Massey University Veterinary Teaching Hospital, on sheep and beef farms or on premises where horses were present. All animals were healthy and were categorised as Urban dogs and cats (minimal contact with horses or farm livestock), Farm dogs (minimal contact with horses) and Stable dogs and cats (frequent contact with horses). Swabs were cultured for β-haemolytic Streptococcus spp. and Lancefield group C streptococcal subspecies were confirmed by phenotypic and molecular techniques. Of the 197 dogs sampled, 21 (10.7 (95% CI= 4.0-25.4)%) tested positive for S. dysgalactiae subsp. equisimilis and 4 (2.0 (95% CI=0.7-5.5)%) tested positive for S. equi subsp. zooepidemicus. All these isolates, except for one S. dysgalactiae subsp. equisimilis isolate in an Urban dog, were from Stable dogs. S. dysgalactiae subsp. equisimilis was isolated from one Stable cat. Of the 93 horses, 22 (23.7 (95% CI=12.3-40.6)%) and 6 (6.5 (95% CI=2.8-14.1)%) had confirmed S. dysgalactiae subsp. equisimilis and S. equi subsp. zooepidemicus isolation respectively. Isolation of S. dysgalactiae subsp. equisimilis from dogs was associated with frequent contact with horses (OR=9.8 (95% CI=2.6-72.8)). Three different multilocus sequence type profiles of S. equi subsp. zooepidemicus that have not been previously reported in dogs were recovered. Subclinical infection or colonisation by S. equi subsp. zooepidemicus and S. dysgalactiae subsp. equisimilis occurs in dogs and further research on inter-species transmission and the pathogenic potential of these

Outlining the influence of non-conventional yeasts in wine ageing over lees.

Science.gov (United States)

Belda, Ignacio; Navascués, Eva; Marquina, Domingo; Santos, Antonio; Calderón, Fernando; Benito, Santiago

2016-07-01

During the last decade, the use of innovative yeast cultures of both Saccharomyces cerevisiae and non-Saccharomyces yeasts as alternative tools to manage the winemaking process have turned the oenology industry. Although the contribution of different yeast species to wine quality during fermentation is increasingly understood, information about their role in wine ageing over lees is really scarce. This work aims to analyse the incidence of three non-Saccharomyces yeast species of oenological interest (Torulaspora delbrueckii, Lachancea thermotolerans and Metschnikowia pulcherrima) and of a commercial mannoprotein-overproducer S. cerevisiae strain compared with a conventional industrial yeast strain during wine ageing over lees. To evaluate their incidence in mouthfeel properties of wine after 4 months of ageing, the mannoprotein content of wines was evaluated, together with other wine analytic parameters, such as colour and aroma, biogenic amines and amino acids profile. Some differences among the studied parameters were observed during the study, especially regarding the mannoprotein concentration of wines. Our results suggest that the use of T. delbrueckii lees in wine ageing is a useful tool for the improvement of overall wine quality by notably increasing mannoproteins, reaching values higher than obtained using a S. cerevisiae overproducer strain. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Technical note: development of a quantitative PCR method for monitoring strain dynamics during yogurt manufacture.

Science.gov (United States)

Miller, D M; Dudley, E G; Roberts, R F

2012-09-01

Yogurt starter cultures may consist of multiple strains of Lactobacillus delbrueckii ssp. bulgaricus (LB) and Streptococcus thermophilus (ST). Conventional plating methods for monitoring LB and ST levels during yogurt manufacture do not allow for quantification of individual strains. The objective of the present work was to develop a quantitative PCR method for quantification of individual strains in a commercial yogurt starter culture. Strain-specific primers were designed for 2 ST strains (ST DGCC7796 and ST DGCC7710), 1 LB strain (DGCC4078), and 1 Lactobacillus delbrueckii ssp. lactis strain (LL; DGCC4550). Primers for the individual ST and LB strains were designed to target unique DNA sequences in clustered regularly interspersed short palindromic repeats. Primers for LL were designed to target a putative mannitol-specific IIbC component of the phosphotransferase system. Following evaluation of primer specificity, standard curves relating cell number to cycle threshold were prepared for each strain individually and in combination in yogurt mix, and no significant differences in the slopes were observed. Strain balance data was collected for yogurt prepared at 41 and 43°C to demonstrate the potential application of this method. Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Effect of addition of Versagel on microbial, chemical, and physical properties of low-fat yogurt.

Science.gov (United States)

Ramchandran, L; Shah, N P

2008-09-01

The objective of this study was to examine the effect of Versagel on the growth and proteolytic activity of Streptococcus thermophilus 1275 and Lactobacillus delbrueckii ssp. bulgaricus 1368 and angiotensin-I converting enzyme inhibitory activity of the peptides generated thereby as well as on the physical properties of low-fat yogurt during a storage period of 28 d at 4 degrees C. Three different types of low-fat yogurts, YV0, YV1, and YV2, were prepared using Versagel as a fat replacer. The fermentation time of the low-fat yogurts containing Versagel was less than that of the control yogurt (YV0). The starter cultures maintained their viability (8.68 to 8.81 log CFU/g of S. thermophilus and 8.51 to 8.81 log CFU/g of L. delbrueckii ssp. bulgaricus) in all the yogurts throughout the storage period. There was some decrease in the pH of the yogurts during storage and an increase in the concentration of lactic acid. However, the proteolytic and ACE-inhibitory potential of the starter cultures was suppressed in the presence of Versagel. On the other hand, the addition of Versagel had a positive impact on the physical properties of the low-fat yogurt, namely, spontaneous whey separation, firmness, and pseudoplastic properties.

Evaluation of the Components Released by Wine Yeast Strains on Protein Haze Formation in White Wine

Directory of Open Access Journals (Sweden)

Ellen Cristine Giese

2016-12-01

Full Text Available Cultures of 23 indigenous yeast strains (22 Saccharomyces cerevisiae and a non-Saccharomyces, Torulaspora delbrueckii, isolated from fermentation tanks at wineries in Castilla-La Mancha (Spain, and were performed under winemaking conditions using a synthetic must. Polysaccharide analysis and turbidity assays were conducted so as to observe the capacity of the released mannoproteins against protein haze formation in white wine, and 3 strains (2 Saccharomyces cerevisiae and T. delbrueckii were chosen for further experiments. The action of a commercial b-glucanolytic enzyme preparation (Lallzyme BETA®, and a β-(1→3-glucanase preparation from Trichoderma harzianum Rifai were evaluated to release polysaccharides from the different yeast strains’ cell walls. Protection against protein haze formation was strain dependent, and only two strains (Sc2 and Sc4 presented >50% stabilization in comparison to controls. Addition of β-glucanases did not increase the concentrations of polysaccharides in the fermentation musts; however, a significant increase of polymeric mannose (mannoproteins was detected using an enzymatic assay following total acid hydrolysis of the soluble polysaccharides. Enzymatic treatment presented positive effects and decreased protein haze formation in white wine. DOI http://dx.doi.org/10.17807/orbital.v8i6.869

Non-Conventional Yeast Strains Increase the Aroma Complexity of Bread

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Rezaei, Mohammad Naser; Steensels, Jan; Courtin, Christophe M.; Verstrepen, Kevin J.

2016-01-01

Saccharomyces cerevisiae is routinely used yeast in food fermentations because it combines several key traits, including fermentation efficiency and production of desirable flavors. However, the dominance of S. cerevisiae in industrial fermentations limits the diversity in the aroma profiles of the end products. Hence, there is a growing interest in non-conventional yeast strains that can help generate the diversity and complexity desired in today’s diversified and consumer-driven markets. Here, we selected a set of non-conventional yeast strains to examine their potential for bread fermentation. Here, we tested ten non-conventional yeasts for bread fermentation, including two Saccharomyces species that are not currently used in bread making and 8 non-Saccharomyces strains. The results show that Torulaspora delbrueckii and Saccharomyces bayanus combine satisfactory dough fermentation with an interesting flavor profile. Sensory analysis and HS-SPME-GC-MS analysis confirmed that these strains produce aroma profiles that are very different from that produced by a commercial bakery strain. Moreover, bread produced with these yeasts was preferred by a majority of a trained sensory panel. These results demonstrate the potential of T. delbrueckii and S. bayanus as alternative yeasts for bread dough leavening, and provide a general experimental framework for the evaluation of more yeasts and bacteria. PMID:27776154

Non-Conventional Yeast Strains Increase the Aroma Complexity of Bread.

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Aslankoohi, Elham; Herrera-Malaver, Beatriz; Rezaei, Mohammad Naser; Steensels, Jan; Courtin, Christophe M; Verstrepen, Kevin J

2016-01-01

Saccharomyces cerevisiae is routinely used yeast in food fermentations because it combines several key traits, including fermentation efficiency and production of desirable flavors. However, the dominance of S. cerevisiae in industrial fermentations limits the diversity in the aroma profiles of the end products. Hence, there is a growing interest in non-conventional yeast strains that can help generate the diversity and complexity desired in today's diversified and consumer-driven markets. Here, we selected a set of non-conventional yeast strains to examine their potential for bread fermentation. Here, we tested ten non-conventional yeasts for bread fermentation, including two Saccharomyces species that are not currently used in bread making and 8 non-Saccharomyces strains. The results show that Torulaspora delbrueckii and Saccharomyces bayanus combine satisfactory dough fermentation with an interesting flavor profile. Sensory analysis and HS-SPME-GC-MS analysis confirmed that these strains produce aroma profiles that are very different from that produced by a commercial bakery strain. Moreover, bread produced with these yeasts was preferred by a majority of a trained sensory panel. These results demonstrate the potential of T. delbrueckii and S. bayanus as alternative yeasts for bread dough leavening, and provide a general experimental framework for the evaluation of more yeasts and bacteria.

Non-Conventional Yeast Strains Increase the Aroma Complexity of Bread.

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Elham Aslankoohi

Full Text Available Saccharomyces cerevisiae is routinely used yeast in food fermentations because it combines several key traits, including fermentation efficiency and production of desirable flavors. However, the dominance of S. cerevisiae in industrial fermentations limits the diversity in the aroma profiles of the end products. Hence, there is a growing interest in non-conventional yeast strains that can help generate the diversity and complexity desired in today's diversified and consumer-driven markets. Here, we selected a set of non-conventional yeast strains to examine their potential for bread fermentation. Here, we tested ten non-conventional yeasts for bread fermentation, including two Saccharomyces species that are not currently used in bread making and 8 non-Saccharomyces strains. The results show that Torulaspora delbrueckii and Saccharomyces bayanus combine satisfactory dough fermentation with an interesting flavor profile. Sensory analysis and HS-SPME-GC-MS analysis confirmed that these strains produce aroma profiles that are very different from that produced by a commercial bakery strain. Moreover, bread produced with these yeasts was preferred by a majority of a trained sensory panel. These results demonstrate the potential of T. delbrueckii and S. bayanus as alternative yeasts for bread dough leavening, and provide a general experimental framework for the evaluation of more yeasts and bacteria.

The investigation of probiotic potential of lactic acid bacteria isolated from traditional Mongolian dairy products.

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Takeda, Shiro; Yamasaki, Keiko; Takeshita, Masahiko; Kikuchi, Yukiharu; Tsend-Ayush, Chuluunbat; Dashnyam, Bumbein; Ahhmed, Abdulatef M; Kawahara, Satoshi; Muguruma, Michio

2011-08-01

The aims of this study were to investigate the diversity of lactic acid bacteria (LAB) isolated from traditional Mongolian dairy products, and to estimate the probiotic potential of the isolated strains. We collected 66 samples of the traditional Mongolian dairy products tarag (n = 45), airag (n = 7), aaruul (n = 8), byasulag (n = 1) and eezgii (n = 5), from which 543 LAB strains were isolated and identified based on 16S ribosomal DNA sequence. The predominant species of those products were Lactobacillus (L.) delbrueckii ssp. bulgaricus, L. helveticus, L. fermentum, L. delbrueckii ssp. lactis and Lactococcus lactis ssp. lactis. However, we could not detect any LAB strains from eezgii. All LAB isolates were screened for tolerance to low pH and to bile acid, gas production from glucose, and adherence to Caco-2 cells. In vitro, we found 10 strains possess probiotic properties, and almost identified them as L. plantarum or L. paracasei subspecies, based on 16S ribosomal DNA and carbohydrate fermentation pattern. These strains were differentiated from each other individually by randomly amplified polymorphic DNA analysis. Additionally, it was notable that 6/10 strains were isolated from camel milk tarag from the Dornogovi province. 2011 The Authors. Animal Science Journal © 2011 Japanese Society of Animal Science.

The application of non-Saccharomyces yeast in fermentations with limited aeration as a strategy for the production of wine with reduced alcohol content.

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Contreras, A; Hidalgo, C; Schmidt, S; Henschke, P A; Curtin, C; Varela, C

2015-07-16

High alcohol concentrations reduce the complexity of wine sensory properties. In addition, health and economic drivers have the wine industry actively seeking technologies that facilitate the production of wines with lower alcohol content. One of the simplest approaches to achieve this aim would be the use of wine yeast strains which are less efficient at transforming grape sugars into ethanol, however commercially available wine yeasts produce very similar ethanol yields. Non-conventional yeast, in particular non-Saccharomyces species, have shown potential for producing wines with lower alcohol content. These yeasts are naturally present in the early stages of fermentation but in general are not capable of completing alcoholic fermentation. We have evaluated 48 non-Saccharomyces isolates to identify strains that, with limited aeration and in sequential inoculation regimes with S. cerevisiae, could be used for the production of wine with lower ethanol concentration. Two of these, Torulaspora delbrueckii AWRI1152 and Zygosaccharomyces bailii AWRI1578, enabled the production of wine with reduced ethanol concentration under limited aerobic conditions. Depending on the aeration regime T. delbrueckii AWRI1152 and Z. bailii AWRI1578 showed a reduction in ethanol concentration of 1.5% (v/v) and 2.0% (v/v) respectively, compared to the S. cerevisiae anaerobic control. Copyright © 2015 Elsevier B.V. All rights reserved.

Gene knockout and overexpression analysis revealed the role of N-acetylmuramidase in autolysis of Lactobacillus delbrueckii subsp. bulgaricus ljj-6.

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Xiao-Yang Pang

Full Text Available Autolysis of lactic acid bacteria (LAB plays a vital role in dairy processing. During cheese making, autolysis of LAB affects cheese flavor development through release of intracellular enzymes and restricts the proliferation of cells in yogurt fermentation and probiotics production. In order to explore the mechanism of autolysis, the gene for the autolytic enzymes of L. bulgaricus, N-acetylmuramidase (mur, was cloned and sequenced (GenBank accession number: KF157911. Mur gene overexpression and gene knockout vectors were constructed based on pMG76e and pUC19 vectors. Recombinant plasmids were transformed into L. bulgaricus ljj-6 by electroporation, then three engineered strains with pMG76e-mur vector and fifteen engineered strains with pUC19-mur::EryBII were screened. The autolysis of the mur knockout strain was significantly lower and autolysis of the mur overexpressed strain was significantly higher compared with that of the wild type strain ljj-6. This result suggested that the mur gene played an important role in autolysis of L. bulgaricus. On the other hand, autolytic activity in a low degree was still observed in the mur knockout strain, which implied that other enzymes but autolysin encoded by mur were also involved in autolysis of L. bulgaricus.

Gene knockout and overexpression analysis revealed the role of N-acetylmuramidase in autolysis of Lactobacillus delbrueckii subsp. bulgaricus ljj-6.

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Pang, Xiao-Yang; Cui, Wen-Ming; Liu, Lu; Zhang, Shu-Wen; Lv, Jia-Ping

2014-01-01

Autolysis of lactic acid bacteria (LAB) plays a vital role in dairy processing. During cheese making, autolysis of LAB affects cheese flavor development through release of intracellular enzymes and restricts the proliferation of cells in yogurt fermentation and probiotics production. In order to explore the mechanism of autolysis, the gene for the autolytic enzymes of L. bulgaricus, N-acetylmuramidase (mur), was cloned and sequenced (GenBank accession number: KF157911). Mur gene overexpression and gene knockout vectors were constructed based on pMG76e and pUC19 vectors. Recombinant plasmids were transformed into L. bulgaricus ljj-6 by electroporation, then three engineered strains with pMG76e-mur vector and fifteen engineered strains with pUC19-mur::EryBII were screened. The autolysis of the mur knockout strain was significantly lower and autolysis of the mur overexpressed strain was significantly higher compared with that of the wild type strain ljj-6. This result suggested that the mur gene played an important role in autolysis of L. bulgaricus. On the other hand, autolytic activity in a low degree was still observed in the mur knockout strain, which implied that other enzymes but autolysin encoded by mur were also involved in autolysis of L. bulgaricus.

Identification of Mycobacterium avium subsp. hominissuis Isolated From Drinking Water

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Mycobacterium avium (MA) is divided into four subspecies based primarily on host-range and consists of MA subsp. avium (birds), MA subsp. silvaticum (wood pigeons), MA subsp. paratuberculosis (broad, poorly-defined host range), and the recently described MA subsp. hominissuis (hu...

Scarce Evidence of Yogurt Lactic Acid Bacteria in Human Feces after Daily Yogurt Consumption by Healthy Volunteers

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del Campo, Rosa; Bravo, Daniel; Cantón, Rafael; Ruiz-Garbajosa, Patricia; García-Albiach, Raimundo; Montesi-Libois, Alejandra; Yuste, Francisco-Javier; Abraira, Victor; Baquero, Fernando

2005-01-01

In a double-blind prospective study including 114 healthy young volunteers, the presence in human feces of the yogurt organisms Lactobacillus delbrueckii and Streptococcus thermophilus after repeated yogurt consumption (15 days) was analyzed by culture, specific PCR, and DNA hybridization of total fecal DNA. Detection of yogurt lactic acid bacteria in total fecal DNA by bacterial culture and PCR assay was consistently negative. DNA compatible with yogurt bacteria was found by hybridization ex...

Efeito do teor de sólidos e da concentração de sacarose na acidificação, firmeza e viabilidade de bactérias do iogurte e probióticas em leite fermentado Effect of total solids and sucrose contents on acidity, firmness and viability of yogurt and probiotic bacteria in fermented milk

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Maricê N. Oliveira

2003-12-01

Full Text Available Doze lotes de leites fermentados foram preparados a 42ºC nos quais as variáveis estudadas foram o teor de sólidos totais (12 e 15%, o teor de sacarose (0% e 8% e o tipo de co-cultura (Streptococcus thermophilus e Lactobacillus delbrueckii subsp. bulgaricus ; Streptococcus thermophilus e Lactobacillus acidophilus ; Streptococcus thermophilus e Lactobacillus rhamnosus. Parâmetros cinéticos para a diminuição do pH até 4,5 foram calculados. Determinações físico-químicas e microbiológicas foram realizadas após um e sete dias de armazenamento dos produtos a 4ºC. Com o aumento do teor de sólidos totais e adição de sacarose, a atividade de água do leite diminuiu e o tempo para atingir pH 4,5 variou conforme a co-cultura empregada. Os leites fermentados por S. thermophilus e L. acidphilus (STLA apresentaram pós-acidificação mais acentuada. Aqueles fermentados por S. thermophilus e L. rhamnosus (STLR foram mais estáveis. Os leites contendo maiores teores de sólidos totais foram aqueles com maior acidez total independente da co-cultura usada. Com o aumento do teor de sacarose e de sólidos solúveis houve um aumento da firmeza usando-se as co-culturas STLR e STLA. Após sete dias, o número de bactérias do iogurte e as probióticas não variou significativamente. Em todos os lotes, o número de bactérias probióticas ficou acima do sugerido pela literatura.Twelve batches of fermented milk were prepared at 42ºC where the studied variables were total solids content (12 and 15%, sucrose concentration (0 and 8%, and co-culture type (Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus ; Streptococcus thermophilus and Lactobacillus acidophilus ; Streptococcus thermophilus and Lactobacillus rhamnosus. Kinetic parameters to decrease pH until 4.5 were calculated. Physico-chemical and microbiological determinations were carried out on products after 1 and 7 days of storage at 4ºC. The increase in total solids and

Diversity of the subspecies Bifidobacterium animalis subsp. lactis.

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Bunesova, Vera; Killer, Jiri; Javurkova, Barbora; Vlkova, Eva; Tejnecky, Vaclav; Musilova, Sarka; Rada, Vojtech

2017-04-01

Strains of Bifidobacterium animalis subsp. lactis are well-known health-promoting probiotics used commercially. B. animalis subsp. lactis has been isolated from different sources, and little is known about animal isolates of this taxon. The aim of this study was to examine the genotypic and phenotypic diversity between B. animalis subsp. lactis strains different animal hosts including Cameroon sheep, Barbary sheep, okapi, mouflon, German shepard and to compare to BB12, food isolates and the collection strain DSM 10140. Ten strains of B. animalis subsp. lactis from different sources were characterised by phenotyping, fingerprinting, and multilocus sequence typing (MLST). Regardless of origin, MLST and phylogenetic analyses revealed a close relationship between strains of B. animalis subsp. lactis with commercial and animal origin with the exception of isolates from ovine cheese, mouflon and German Shepard dog. Moreover, isolates from dog and mouflon showed significant differences in fermentation profiles and peptide mass fingerprints (MALDI-TOF). Results indicated phenotypic and genotypic diversity among strains of B. animalis subsp. lactis. Copyright © 2017 Elsevier Ltd. All rights reserved.

Peptidoglycan Hydrolases of Local Lactic Acid Bacteria from Kazakh Traditional Food

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Serik Shaikhin

2014-01-01

Full Text Available Introduction: Peptidoglycan (PG is a major component of the cell wall of Gram-positive bacteria and is essential for maintaining the integrity of the bacterial cell and its shape. The bacteria synthesize PG hydrolases, which are capable of cleaving the covalent bonds of PG. They also play an important role in modeling PG, which is required for bacterial growth and division. In an era of increasing antibiotic-resistant pathogens, PG hydrolases that destroy these important structures of the cell wall act as a potential source of new antimicrobials. The aim of this study is to identify the main PG hydrolases of local lactic acid bacteria isolated from traditional foods that enhance probiotic activity of a biological preparation. Methods. Lactococcus lactis 17А and Lactococcus garvieae 19А were isolated from the traditional sausage-like meat product called kazy. They were isolated according to standards methods of microbiology. Genetic identification of the isolates were tested by determining the nucleotide sequences of 16S rDNA. The Republican collection of microorganisms took strains of Lactobacillus casei subsp. Rhamnosus 13-P, L. delbrueckii subsp. lactis CG-1 B-RKM 0044 from cheese, Lactobacillus casei subsp. casei B-RKM 0202 from homemade butter. They used the standard technique of renaturating polyacrylamide gel electrophoresis to detect PG hydrolases activity. Results. According to the profiles of PG hydrolase activity on zymograms, the enzymes of Lactococci 17A and 19A in kazy are similar in electrophoretic mobility to major autolysin AcmA, while the lactobacilli of industrial and home-made dairy products have enzymes similar to extracellular proteins p40 and p75, which have probiotic activity. Conclusions. Use of peptidoglycan hydrolases seems to be an interesting approach in the fight against multi-drug resistant strains of bacteria and could be a valuable tool for the treatment of diseases caused by these microorganisms in Kazakhstan.

Dynamics of fecal microbiota in hospitalized elderly fed probiotic LKM512 yogurt.

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Matsumoto, Mitsuharu; Sakamoto, Mitsuo; Benno, Yoshimi

2009-08-01

The comprehensive dynamics of intestinal microbiota including uncultured bacteria in response to probiotic consumption have not been well studied. The aims of this study were twofold: firstly to analyze the impact on intestinal microbiota of yogurt fermented by Bifidobacterium animalis subsp. lactis LKM512, Lactobacillus delbrueckii subsp. bulgaricus LKM1759, and Streptococcus thermophilus LKM1742 (LKM512 yogurt) and placebo fermented by these lactic acid bacterial strains without LKM512; and secondly to investigate the changes in intestinal microbiota that influence the concentration of PA, one of the beneficial metabolites produced by bacteria in the intestine. The LKM512 yogurt/placebo trial was performed in six hospitalized elderly patients (three men and three women with an average age of 80.3 years) and lasted seven weeks with the following schedule: pre-consumption for one week, LKM512 yogurt consumption for two weeks, washout period for two weeks, and placebo consumption for two weeks. The amount of ingested LKM512 yogurt or placebo was 100 g/day/individual. Fecal samples were analyzed using T-RFLP and real-time PCR. The T-RFLP patterns in five of the six volunteers were changed in a similar fashion by LKM512 yogurt consumption, although these patterns were individually changed following consumption of placebo. It was confirmed that B. animalis subsp. lactis was increased dramatically and Lactobacillus spp. tended to be decreased by LKM512 yogurt consumption. Some indigenous uncultured bacteria were increased and some decreased by LKM512 yogurt/placebo consumption. The similar changes in the intestinal microbiota of the elderly caused by consumption of the LKM512 yogurt were found to be influenced by the LKM512 strain itself, and not by the lactic acid bacteria in the yogurt. Moreover, this study suggests that the increase in intestinal PA concentrations caused by LKM512 yogurt consumption is probably dependent on the LKM512 strain colonizing the intestine.

Demonstration of Mycoplasma capricolum subsp capripneumoniae and Mycoplasma mycoides subsp mycoides, small colony type in outbreaks of caprine pleuropneumonia in eastern Tanzania

DEFF Research Database (Denmark)

Kusiluka, L.J.M.; Semuguruka, W.D.; Kazwala, R.R.

2000-01-01

by different degrees of vasculitis, and fibrinocellular exudation into the alveolar septae and lumina, and into interlobular septae and pleura. Mycoplasma capricolum subsp. capripneumoniae, Mycoplasma mycoides subsp. mycoides, Small Colony type Mycoplasma ovipneumoniae and Mycoplasma arginini were isolated...... from some of the examined goats including a case with a sequestrum which yielded Mycoplasma mycoides subsp. mycoides, Small Colony type. This work reports the first description of an outbreak of caprine pleuropneumonia in Tanzania in which M. capripneumoniae and M. mycoides subsp. mycoides, Small...

Probiotic viability and storage stability of yogurts and fermented milks prepared with several mixtures of lactic acid bacteria.

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Mani-López, E; Palou, E; López-Malo, A

2014-05-01

Currently, the food industry wants to expand the range of probiotic yogurts but each probiotic bacteria offers different and specific health benefits. Little information exists on the influence of probiotic strains on physicochemical properties and sensory characteristics of yogurts and fermented milks. Six probiotic yogurts or fermented milks and 1 control yogurt were prepared, and we evaluated several physicochemical properties (pH, titratable acidity, texture, color, and syneresis), microbial viability of starter cultures (Lactobacillus delbrueckii ssp. bulgaricus and Streptococcus thermophilus) and probiotics (Lactobacillus acidophilus, Lactobacillus casei, and Lactobacillus reuteri) during fermentation and storage (35 d at 5°C), as well as sensory preference among them. Decreases in pH (0.17 to 0.50 units) and increases in titratable acidity (0.09 to 0.29%) were observed during storage. Only the yogurt with S. thermophilus, L. delbrueckii ssp. bulgaricus, and L. reuteri differed in firmness. No differences in adhesiveness were determined among the tested yogurts, fermented milks, and the control. Syneresis was in the range of 45 to 58%. No changes in color during storage were observed and no color differences were detected among the evaluated fermented milk products. Counts of S. thermophilus decreased from 1.8 to 3.5 log during storage. Counts of L. delbrueckii ssp. bulgaricus also decreased in probiotic yogurts and varied from 30 to 50% of initial population. Probiotic bacteria also lost viability throughout storage, although the 3 probiotic fermented milks maintained counts ≥ 10(7)cfu/mL for 3 wk. Probiotic bacteria had variable viability in yogurts, maintaining counts of L. acidophilus ≥ 10(7) cfu/mL for 35 d, of L. casei for 7d, and of L. reuteri for 14 d. We found no significant sensory preference among the 6 probiotic yogurts and fermented milks or the control. However, the yogurt and fermented milk made with L. casei were better accepted. This

Identification of Lactobacillus species isolated from traditional cheeses of west Azerbaijan

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Ali Ehsani

2014-06-01

Results: In present study, from a total of 118 isolates of lactobacilli were determined. Lactobacillus plantarum (24%, Lactobacillus casei (20% and Lactobacillus agillis (18% from facultative heterofermentative Lactobacilli and Lactobacillus delbrueckii (21%, Lactobacillus helveticus (14% and Lactobacillus salvariu s (3% from obligative homofermentative Lactobacilli were found to be more dominant species.Conclusions: So for achievement to organoleptic characteristics of traditional cheeses in industrial productions, mixed starters including dominant Lactobacillus species identified in cheeses can be employed.

Isolation and identification of lactic acid bacteria from koumiss in Eastern Inner Mongolia of China

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Bai, Lijuan; Ji, Shujuan

2017-01-01

Koumiss is a traditional fermented dairy product and known as its unique physiological actions. Isolation and identification of LAB in it will yield valuable knowledge. In total, 55 LAB strains were isolated and identified of 12 koumiss samples collected in limited regions of Eastern Inner Mongolia. 16S rRNA sequence analysis results showed that were Lactobacillus helveticus, Lactobacillus casei, Lactobacillus plantarum, Lactobacillus delbrueckii, Enterococcus. durans, Leuconostoc lactis and Leuconostoc mesenteroides. It is benefit to further research on koumiss.

Genetic Diversity of Pectobacterium carotovorum subsp. brasiliensis Isolated in Korea

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Dong Hwan Lee

2014-06-01

Full Text Available The plant pathogenic bacterial genus Pectobacteirum consists of heterogeneous strains. The P. carotovorum species is a complex strain showing divergent characteristics, and a new subspecies named P. carotovorum subsp. brasiliensis has been identified recently. In this paper, we re-identified the P. carotovorum subsp. brasiliensis isolates from those classified under the subspecies carotovorum and newly isolated P. carotovorum subsp. brasiliensis strains. All isolates were able to produce plant cell-wall degrading enzymes such as pectate lyase, polygalacturonase, cellulase and protease. We used genetic and biochemical methods to examine the diversity of P. carotovorum subsp. brasiliensis isolates, and found genetic diversity within the brasiliensis subsp. isolates in Korea. The restriction fragment length polymorphism analysis based on the recA gene revealed a unique pattern for the brasiliensis subspecies. The Korean brasiliensis subsp. isolates were divided into four clades based on pulsed-field gel electrophoresis. However, correlations between clades and isolated hosts or year could not be found, suggesting that diverse brasiliensis subsp. isolates existed.

Description of Mycobacterium chelonae subsp. bovis subsp. nov., isolated from cattle (Bos taurus coreanae), emended description of Mycobacterium chelonae and creation of Mycobacterium chelonae subsp. chelonae subsp. nov.

Science.gov (United States)

Kim, Byoung-Jun; Kim, Ga-Na; Kim, Bo-Ram; Jeon, Che Ok; Jeong, Joseph; Lee, Seon Ho; Lim, Ji-Hun; Lee, Seung-Heon; Kim, Chang Ki; Kook, Yoon-Hoh; Kim, Bum-Joon

2017-10-01

Three rapidly growing mycobacterial strains, QIA-37 T , QIA-40 and QIA-41, were isolated from the lymph nodes of three separate Korean native cattle, Hanwoo (Bos taurus coreanae). These strains were previously shown to be phylogenetically distinct but closely related to Mycobacterium chelonae ATCC 35752 T by taxonomic approaches targeting three genes (16S rRNA, hsp6 and rpoB) and were further characterized using a polyphasic approach in this study. The 16S rRNA gene sequences of all three strains showed 99.7 % sequence similarity with that of the M. chelonae type strain. A multilocus sequence typing analysis targeting 10 housekeeping genes, including hsp65 and rpoB, revealed a phylogenetic cluster of these strains with M. chelonae. DNA-DNA hybridization values of 78.2 % between QIA-37 T and M. chelonae indicated that it belongs to M. chelonae but is a novel subspecies distinct from M. chelonae. Phylogenetic analysis based on whole-genome sequences revealed a 95.44±0.06 % average nucleotide identity (ANI) value with M. chelonae, slightly higher than the 95.0 % ANI criterion for determining a novel species. In addition, distinct phenotypic characteristics such as positive growth at 37 °C, at which temperature M. chelonae does not grow, further support the taxonomic status of these strains as representatives of a novel subspecies of M. chelonae. Therefore, we propose an emended description of Mycobacterium chelonae, and descriptions of M. chelonae subsp. chelonae subsp. nov. and M. chelonae subsp. bovis subsp. nov. are presented; strains ATCC 35752 T (=CCUG 47445 T =CIP 104535 T =DSM 43804 T =JCM 6388 T =NCTC 946 T ) and QIA-37 T (=KCTC 39630 T =JCM 30986 T ) are the type strains of the two novel subspecies.

In vitro selection of bacteria with potential for use as probiotics in marine shrimp culture

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Felipe do Nascimento Vieira

2013-08-01

Full Text Available The objective of this work was to isolate strains of lactic acid bacteria with probiotic potential from the digestive tract of marine shrimp (Litopenaeus vannamei, and to carry out in vitro selection based on multiple characters. The ideotype (ideal proposed strain was defined by the highest averages for the traits maximum growth velocity, final count of viable cells, and inhibition halo against nine freshwater and marine pathogens, and by the lowest averages for the traits duplication time and resistance of strains to NaCl (1.5 and 3%, pH (6, 8, and 9, and biliary salts (5%. Mahalanobis distance (D² was estimated among the evaluated strains, and the best ones were those with the shortest distances to the ideotype. Ten bacterial strains were isolated and biochemically identified as Lactobacillus plantarum (3, L. brevis (3, Weissella confusa (2, Lactococcus lactis (1, and L. delbrueckii (1. Lactobacillus plantarum strains showed a wide spectrum of action and the largest inhibition halos against pathogens, both Gram-positive and negative, high growth rate, and tolerance to all evaluated parameters. In relation to ideotype, L. plantarum showed the lowest Mahalanobis (D² distance, followed by the strains of W. confusa, L. brevis, L. lactis, and L. delbrueckii. Among the analyzed bacterial strains, those of Lactobacillus plantarum have the greatest potential for use as a probiotic for marine shrimp.

Yeast Monitoring of Wine Mixed or Sequential Fermentations Made by Native Strains from D.O. “Vinos de Madrid” Using Real-Time Quantitative PCR

Science.gov (United States)

García, Margarita; Esteve-Zarzoso, Braulio; Crespo, Julia; Cabellos, Juan M.; Arroyo, Teresa

2017-01-01

There is an increasing trend toward understanding the impact of non-Saccharomyces yeasts on the winemaking process. Although Saccharomyces cerevisiae is the predominant species at the end of fermentation, it has been recognized that the presence of non-Saccharomyces species during alcoholic fermentation can produce an improvement in the quality and complexity of the final wines. A previous work was developed for selecting the best combinations between S. cerevisiae and five non-Saccharomyces (Torulaspora delbrueckii, Schizosaccharomyces pombe, Candida stellata, Metschnikowia pulcherrima, and Lachancea thermotolorans) native yeast strains from D.O. “Vinos de Madrid” at the laboratory scale. The best inoculation strategies between S. cerevisiae and non-Saccharomyces strains were chosen to analyze, by real-time quantitative PCR (qPCR) combined with the use of specific primers, the dynamics of inoculated populations throughout the fermentation process at the pilot scale using the Malvar white grape variety. The efficiency of the qPCR system was verified independently of the samples matrix, founding the inoculated yeast species throughout alcoholic fermentation. Finally, we can validate the positive effect of selected co-cultures in the Malvar wine quality, highlighting the sequential cultures of T. delbrueckii CLI 918/S. cerevisiae CLI 889 and C. stellata CLI 920/S. cerevisiae CLI 889 and, mixed and sequential cultures of L. thermotolerans 9-6C combined with S. cerevisiae CLI 889. PMID:29326669

Yeast Monitoring of Wine Mixed or Sequential Fermentations Made by Native Strains from D.O. “Vinos de Madrid” Using Real-Time Quantitative PCR

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Margarita García

2017-12-01

Full Text Available There is an increasing trend toward understanding the impact of non-Saccharomyces yeasts on the winemaking process. Although Saccharomyces cerevisiae is the predominant species at the end of fermentation, it has been recognized that the presence of non-Saccharomyces species during alcoholic fermentation can produce an improvement in the quality and complexity of the final wines. A previous work was developed for selecting the best combinations between S. cerevisiae and five non-Saccharomyces (Torulaspora delbrueckii, Schizosaccharomyces pombe, Candida stellata, Metschnikowia pulcherrima, and Lachancea thermotolorans native yeast strains from D.O. “Vinos de Madrid” at the laboratory scale. The best inoculation strategies between S. cerevisiae and non-Saccharomyces strains were chosen to analyze, by real-time quantitative PCR (qPCR combined with the use of specific primers, the dynamics of inoculated populations throughout the fermentation process at the pilot scale using the Malvar white grape variety. The efficiency of the qPCR system was verified independently of the samples matrix, founding the inoculated yeast species throughout alcoholic fermentation. Finally, we can validate the positive effect of selected co-cultures in the Malvar wine quality, highlighting the sequential cultures of T. delbrueckii CLI 918/S. cerevisiae CLI 889 and C. stellata CLI 920/S. cerevisiae CLI 889 and, mixed and sequential cultures of L. thermotolerans 9-6C combined with S. cerevisiae CLI 889.

Yeast communities associated with artisanal mezcal fermentations from Agave salmiana.

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Verdugo Valdez, A; Segura Garcia, L; Kirchmayr, M; Ramírez Rodríguez, P; González Esquinca, A; Coria, R; Gschaedler Mathis, A

2011-11-01

The aims of this work were to characterize the fermentation process of mezcal from San Luis Potosi, México and identify the yeasts present in the fermentation using molecular culture-dependent methods (RFLP of the 5.8S-ITS and sequencing of the D1/D2 domain) and also by using a culture-independent method (DGGE). The alcoholic fermentations of two separate musts obtained from Agave salmiana were analyzed. Sugar, ethanol and major volatile compounds concentrations were higher in the first fermentation, which shows the importance of having a quality standard for raw materials, particularly in the concentration of fructans, in order to produce fermented Agave salmiana must with similar characteristics. One hundred ninety-two (192) different yeast colonies were identified, from those present on WL agar plates, by RFLP analysis of the ITS1-5.8S- ITS2 from the rRNA gene, with restriction endonucleases, HhaI, HaeIII and HinfI. The identified yeasts were: Saccharomyces cerevisiae, Kluyveromyces marxianus, Pichia kluyveri, Zygosaccharomyces bailii, Clavispora lusitaniae, Torulaspora delbrueckii, Candida ethanolica and Saccharomyces exiguus. These identifications were confirmed by sequencing the D1-D2 region of the 26S rRNA gene. With the PCR-DGGE method, bands corresponding to S. cerevisiae, K. marxianus and T. delbrueckii were clearly detected, confirming the results obtained with classic techniques.

Encapsulation in alginate-skim milk microspheres improves viability of Lactobacillus bulgaricus in stimulated gastrointestinal conditions.

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Pan, Ling-Xia; Fang, Xiu-Juan; Yu, Zhen; Xin, Yang; Liu, Xiao-Ying; Shi, Lu-E; Tang, Zhen-Xing

2013-05-01

Lactobacillus delbrueckii subsp. bulgaricus (L. bulgaricus) was encapsulated in alginate-skim milk microspheres. Characteristics of encapsulated L. bulgaricus, such as pH stability, bile stability, storage stability and release property, were studied in this paper. The viability of free L. bulgaricus was not observed after 1 min in simulated gastric fluids (SGF) at pH 2.5 or 2.0. Compared with that of free L. bulgaricus, the viability of encapsulated L. bulgaricus only decreased 0.7 log CFU/g and 2 log CFU/g after 2.0 h incubation in SGF at pH 2.5 and pH 2.0, respectively. L. bulgaricus was also sensitive to bile solution. The viability of free L. bulgaricus was fully lost after 1 h incubation in 1 and 2% bile solution, while the viability of encapsulated L. bulgaricus was only lost 2 log CFU/g and 2.6 log CFU/g in 1 and 2% bile solution at the same time, respectively. Encapsulated L. bulgaricus could be completely released from microspheres in simulated intestinal fluid (pH 6.8) within 2 h. The viability of encapsulated L. bulgaricus retained around 8 log CFU/g when stored at 4°C for 30 days. The current encapsulation technique enables a large proportion of L. bulgaricus to remain good bioactive in a simulated gastrointestinal tract environment.

Benzoic Acid Production with Respect to Starter Culture and Incubation Temperature during Yogurt Fermentation using Response Surface Methodology.

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Yu, Hyung-Seok; Lee, Na-Kyoung; Jeon, Hye-Lin; Eom, Su Jin; Yoo, Mi-Young; Lim, Sang-Dong; Paik, Hyun-Dong

2016-01-01

Benzoic acid is occasionally used as a raw material supplement in food products and is sometimes generated during the fermentation process. In this study, the production of naturally occurring yogurt preservatives was investigated for various starter cultures and incubation temperatures, and considered food regulations. Streptococcus thermophilus, Lactobacillus acidophilus, Lactobacillus delbrueckii subsp. bulgaricus, Lactobacillus rhamnosus, Lactobacillus casei, Lactobacillus paracasei, Lactobacillus reuteri, Lactobacillus plantarum, Bifidobacterium longum, Bifidobacterium lactis, Bifidobacterium bifidum, Bifidobacterium infantis, and Bifidobacterium breve were used as yogurt starter cultures in commercial starters. Among these strains, L. rhamnosus and L. paracasei showed the highest production of benzoic acid. Therefore, the use of L. rhamnosus, L. paracasei, S. thermophilus, and different incubation temperatures were examined to optimize benzoic acid production. Response surface methodology (RSM) based on a central composite design was performed for various incubation temperatures (35-44℃) and starter culture inoculum ratios (0-0.04%) in a commercial range of dairy fermentation processes. The optimum conditions were 0.04% L. rhamnosus, 0.01% L. paracasei, 0.02% S. thermophilus, and 38.12℃, and the predicted and estimated concentrations of benzoic acid were 13.31 and 13.94 mg/kg, respectively. These conditions maximized naturally occurring benzoic acid production during the yogurt fermentation process, and the observed production levels satisfied regulatory guidelines for benzoic acid in dairy products.

Activity of encapsulated Lactobacillus bulgaricus in alginate-whey protein microspheres

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Meng-Yan Chen

2014-10-01

Full Text Available In this work, alginate-whey protein was used as wall materials for encapsulating Lactobacillus delbrueckii subsp. bulgaricus (L. bulgaricus. The characteristics of encapsulated and free L. bulgaricus showed that the free L. bulgaricus lost viability after 1 min exposure to simulated gastric fluid (SGF at pH 2.0 and 2.5. However, the viability of encapsulated L. bulgaricus did not decrease in SGF at pH 2.5 for 2 h incubation. The viable numbers of encapsulated L. bulgaricus decreased less than 1.0 log unit for 2 h incubation in SGF at pH 2.0. For bile stability, only 1.2 log units and 2.0 log units viability of the encapsulated L. bulgaricus was lost in 1 and 2% bile for 1 h exposure, respectively, compared with no survival of free L. bulgaricus under the same conditions. Encapsulated L. bulgaricus was completely released from the microspheres in simulated intestinal fluid (SIF, pH 6.8 in 3 h. The viability of the encapsulated L. bulgaricus retained more 8.0 log CFU/g after stored at 4°C for four weeks. However, for free L. bulgaricus, only around 3.0 log CFU/mL was found at the same storage conditions. Results showed that the encapsulation could improve the stability of L. bulgaricus.

Influence of Lactobacillus plantarum WCFS1 on post-acidification, metabolite formation and survival of starter bacteria in set-yoghurt.

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Settachaimongkon, Sarn; van Valenberg, Hein J F; Gazi, Inge; Nout, M J Robert; van Hooijdonk, Toon C M; Zwietering, Marcel H; Smid, Eddy J

2016-10-01

The objectives of this study were to evaluate the growth and survival of the model probiotic strain Lactobacillus plantarum WCFS1 in co-culture with traditional yoghurt starters and to investigate the impact of preculturing on their survival and metabolite formation in set-yoghurt. L. plantarum WCFS1 was precultured under sublethal stress conditions (combinations of elevated NaCl and low pH) in a batch fermentor before inoculation in milk. Adaptive responses of L. plantarum WCFS1 were evaluated by monitoring bacterial population dynamics, milk acidification and changes in volatile and non-volatile metabolite profiles of set-yoghurt. The results demonstrated that sublethal preculturing did not significantly affect survival of L. plantarum WCFS1. On the other hand, incorporation of sublethally precultured L. plantarum WCFS1 significantly impaired the survival of Lactobacillus delbrueckii subsp. bulgaricus which consequently reduced the post-acidification of yoghurt during refrigerated storage. A complementary metabolomics approach using headspace SPME-GC/MS and (1)H NMR combined with multivariate statistical analysis revealed substantial impact of sublethally precultured L. plantarum WCFS1 on the metabolite profiles of set-yoghurt. This study provides insight in the technological implications of non-dairy model probiotic strain L. plantarum WCFS1, such as its good stability in fermented milk and the inhibitory effect on post-acidification. Copyright © 2016 Elsevier Ltd. All rights reserved.

The impact of heterologous catalase expression and superoxide dismutase overexpression on enhancing the oxidative resistance in Lactobacillus casei.

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Lin, Jinzhong; Zou, Yexia; Cao, Kunlin; Ma, Chengjie; Chen, Zhengjun

2016-05-01

Two heme-dependent catalase genes were amplified from genomic DNA of Lactobacillus plantarum WCFS1 (KatE1) and Lactobacillus brevis ATCC 367 (KatE2), respectively, and a manganese-containing superoxide dismutase from Lactobacillus casei MCJΔ1 (MnSOD) were cloned into plasmid pELX1, yielding pELX1-KatE1, pELX1-KatE2 and pELX1-MnSOD, then the recombinant plasmids were transferred into L. casei MCJΔ1. The strains of L. casei MCJΔ1/pELX1-KatE1 and L. casei MCJΔ1/pELX1-KatE2 were tolerant at 2 mM H2O2. The survival rates of L. casei MCJΔ1/pELX1-KatE1 and L. casei MCJΔ1/pELX1-KatE2 were 270-fold and 300-fold higher than that of the control strain on a short-term H2O2 exposure, and in aerated condition, the survival cells counts were 146- and 190-fold higher than that of the control strain after 96 h of incubation. Furthermore, L. casei MCJΔ1/pELX1-MnSOD was the best in three recombinants which was superior in the living cell viability during storage when co-storage with Lactobacillus delbrueckii subsp. lactis LBCH-1.

Functional role of pyruvate kinase from Lactobacillus bulgaricus in acid tolerance and identification of its transcription factor by bacterial one-hybrid.

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Zhai, Zhengyuan; An, Haoran; Wang, Guohong; Luo, Yunbo; Hao, Yanling

2015-11-19

Lactobacillus delbrueckii subsp. bulgaricus develops acid tolerance response when subjected to acid stress conditions, such as the induction of enzymes associated with carbohydrate metabolism. In this study, pyk gene encoding pyruvate kinase was over-expressed in heterologous host Lactococcus lactis NZ9000, and SDS-PAGE analysis revealed the successful expression of this gene in NZ9000. The survival rate of Pyk-overproducing strain was 45-fold higher than the control under acid stress condition (pH 4.0). In order to determine the transcription factor (TF) which regulates the expression of pyk by bacterial one-hybrid, we constructed a TF library including 65 TFs of L. bulgaricus. Western blotting indicated that TFs in this library could be successfully expressed in host strains. Subsequently, the promoter of pfk-pyk operon in L. bulgaricus was identified by 5'-RACE PCR. The bait plasmid pH3U3-p01 carrying the deletion fragment of pfk-pyk promoter captured catabolite control protein A (CcpA) which could regulate the expression of pyk by binding to a putative catabolite-responsive element (5'-TGTAAGCCCTAACA-3') upstream the -35 region. Real-time qPCR analysis revealed the transcription of pyk was positively regulated by CcpA. This is the first report about identifying the TF of pyk in L. bulgaricus, which will provide new insight into the regulatory network.

Biocontrol of Pectobacterium carotovorum subsp. carotovorum using bacteriophage PP1.

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Lim, Jeong-A; Jee, Samnyu; Lee, Dong Hwan; Roh, Eunjung; Jung, Kyusuk; Oh, Changsik; Heu, Sunggi

2013-08-01

Pectobacterium carotovorum subsp. carotovorum (formerly Erwinia carotovora subsp. carotovora) is a plant pathogen that causes soft rot and stem rot diseases in several crops, including Chinese cabbage, potato, and tomato. To control this bacterium, we isolated a bacteriophage, PP1, with lytic activity against P. carotovorum subsp. carotovorum. Transmission electron microscopy revealed that the PP1 phage belongs to the Podoviridae family of the order Caudovirales, which exhibit icosahedral heads and short non-contractile tails. PP1 phage showed high specificity for P. carotovorum subsp. carotovorum, and several bacteria belonging to different species and phyla were resistant to PP1. This phage showed rapid and strong lytic activity against its host bacteria in liquid medium and was stable over a broad range of pH values. Disease caused by P. carotovorum subsp. carotovorum was significantly reduced by PP1 treatment. Overall, PP1 bacteriophage effectively controls P. carotovorum subsp. carotovorum.

Major Role of NAD-Dependent Lactate Dehydrogenases in the Production of l-Lactic Acid with High Optical Purity by the Thermophile Bacillus coagulans.

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Wang, Limin; Cai, Yumeng; Zhu, Lingfeng; Guo, Honglian; Yu, Bo

2014-12-01

Bacillus coagulans 2-6 is an excellent producer of optically pure l-lactic acid. However, little is known about the mechanism of synthesis of the highly optically pure l-lactic acid produced by this strain. Three enzymes responsible for lactic acid production-NAD-dependent l-lactate dehydrogenase (l-nLDH; encoded by ldhL), NAD-dependent d-lactate dehydrogenase (d-nLDH; encoded by ldhD), and glycolate oxidase (GOX)-were systematically investigated in order to study the relationship between these enzymes and the optical purity of lactic acid. Lactobacillus delbrueckii subsp. bulgaricus DSM 20081 (a d-lactic acid producer) and Lactobacillus plantarum subsp. plantarum DSM 20174 (a dl-lactic acid producer) were also examined in this study as comparative strains, in addition to B. coagulans. The specific activities of key enzymes for lactic acid production in the three strains were characterized in vivo and in vitro, and the levels of transcription of the ldhL, ldhD, and GOX genes during fermentation were also analyzed. The catalytic activities of l-nLDH and d-nLDH were different in l-, d-, and dl-lactic acid producers. Only l-nLDH activity was detected in B. coagulans 2-6 under native conditions, and the level of transcription of ldhL in B. coagulans 2-6 was much higher than that of ldhD or the GOX gene at all growth phases. However, for the two Lactobacillus strains used in this study, ldhD transcription levels were higher than those of ldhL. The high catalytic efficiency of l-nLDH toward pyruvate and the high transcription ratios of ldhL to ldhD and ldhL to the GOX gene provide the key explanations for the high optical purity of l-lactic acid produced by B. coagulans 2-6. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Análisis comparativo del cariotipo en poblaciones de Alstroemeria ligtu subsp. ligtu y A. ligtu subsp. simsii (Alstroemeriaceae de Chile

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Carlos M. Baeza

2006-01-01

Full Text Available Alstroemeria (Alstroemeriaceae es un género endémico de América del Sur. En Chile, este género se distribuye desde el extremo norte hasta la Patagonia, y la mayor diversidad de especies se encuentra en la zona central. Precisamente en esta zona crece Alstroemeria ligtu con sus 3 subespecies: A. ligtu subsp. ligtu, A. ligtu subsp. incarnata, A. ligtu subsp. simsii. Se realizó un estudio comparativo del cariotipo de individuos provenientes de 5 poblaciones de A. ligtu subsp. ligtu de la VIII Región, y de una población de A. ligtu subsp. simsii de la V Región, mediante tinción de los cromosomas con DAPI u orceína acética. Las seis poblaciones estudiadas presentaron un cariotipo asimétrico, con 2n=2x=16 cromosomas. Las poblaciones de A. ligtu subsp. ligtu presentaron una fórmula haploide conformada por cuatro cromosomas metacéntricos (los pares 1 y 2 con microsatélites, uno submetacéntrico con microsatélite y tres telocéntricos con microsatélites. La población de A. ligtu subsp. simsii se caracterizó por poseer cinco cromosomas metacéntricos (el par 2 con un microsatélite y el par 6 con una constricción secundaria y tres cromosomas telocéntricos con satélite. Estos resultados indican que el cariotipo en A. ligtu es variable, y es probable que cambios a nivel cromosómico hayan contribuido en la diversificación de esta especie.

Potential Transmission Pathways of Streptococcus gallolyticus subsp. gallolyticus.

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Jessika Dumke

Full Text Available Streptococcus gallolyticus subsp. gallolyticus (S. gallolyticus subsp. gallolyticus, a member of group D streptococci, is an inhabitant of the animal and human gastrointestinal tract. Furthermore, it is a facultative pathogen which causes e.g. endocarditis, septicemia and mastitis. S. gallolyticus subsp. gallolyticus may be transmitted either directly or indirectly between animals and humans. However, the transmission routes are an unsolved issue. In this study, we present systematic analyses of an S. gallolyticus subsp. gallolyticus isolate of an infective endocarditis patient in relation to isolates of his laying hen flock. Isolates from pooled droppings of laying hens, pooled dust samples and human blood culture were characterized by using multilocus sequence typing (MLST and DNA fingerprinting. MLST revealed the same allelic profile of isolates from the human blood culture and from the droppings of laying hens. In addition, these isolates showed clonal identity regarding a similar DNA fingerprinting pattern. For the first time, we received a hint that transmission of S. gallolyticus subsp. gallolyticus between poultry and humans may occur. This raises the question about the zoonotic potential of isolates from poultry and should be considered in future studies.

Atividade antibacteriana e antioxidante de óleos essenciais cítricos com potencialidade para inclusão como aditivos em alimentos

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Santos, Adriana Oliveira Santos; Freire, Josinaura Aparecida de S.; de Carvalho, Thaís Dantas; Barbosa, Thayara Corrado; Prates, Rodrigo Pereira; Lopes Silva, Júlio César Rodrigues; Farias, Paula Karoline Soares

2016-01-01

Indubitavelmente, os óleos essenciais atraem cada vez mais o interesse da população por sua eficiência orgânica beneficente. O presente trabalho avaliou o potencial antibacteriano e a atividade antioxidante dos óleos essenciais cítricos de Citrus aurantium var. dulcis (laranja doce), Passiflora edulis (maracujá) e Citrus reticulata v. tangerine (tangerina) frente a bactérias lácticas e patogênicas. Foram utilizadas bactérias lácticas de Streptococcus thermophilus e Lactobacillus delbrueckii s...

Isolation of cultivable thermophilic lactic acid bacteria from cheeses made with mesophilic starter and molecular comparison with dairy-related Lactobacillus helveticus strains

DEFF Research Database (Denmark)

Jensen, Marie Elisabeth Penderup; Ardö, Ylva Margareta; Vogensen, Finn Kvist

2009-01-01

-related Lact. helveticus strains indicated that one isolate was a Lact. helveticus. Partial sequencing of 16S rRNA confirmed this, and the remaining four strains were identified as Lactobacillus delbrueckii, Lactobacillus fermentum and Enterococcus faecium. The rep-PCR profile of the isolated Lact. helveticus......Aims: To isolate cultivable thermophilic lactic acid bacteria from cheeses made with mesophilic starter and compare them with dairy-related Lactobacillus helveticus strains using molecular typing methods. Methods and Results: The number of thermophilic bacteria in seven commercial cheeses...

Proteolytic and ACE-inhibitory activities of probiotic yogurt containing non-viable bacteria as affected by different levels of fat, inulin and starter culture

OpenAIRE

Shakerian, Mansour; Razavi, Seyed Hadi; Ziai, Seyed Ali; Khodaiyan, Faramarz; Yarmand, Mohammad Saeid; Moayedi, Ali

2013-01-01

In this study, the effects of fat (0.5 %, 3.2 % and 5.0 %), inulin (0.0 and 1.0 %) and starter culture (0.0 %, 0.5 %, 1.0 % and 1.5 %) on the angiotensin converting enzyme (ACE)-inhibitory activity of probiotic yogurt containing non-viable bacteria were assessed. Proteolytic activities of bacteria were also investigated. Yogurts were prepared either using a sole yogurt commercial culture including Streptococcus thermophilus and Lactobacillus delbrueckii subs. bulgaricus or bifidobacterium ani...

Russian isolates enlarge the known geographic diversity of Francisella tularensis subsp. mediasiatica.

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Vitalii Timofeev

Full Text Available Francisella tularensis, a small Gram-negative bacterium, is capable of infecting a wide range of animals, including humans, and causes a plague-like disease called tularemia-a highly contagious disease with a high mortality rate. Because of these characteristics, F. tularensis is considered a potential agent of biological terrorism. Currently, F. tularensis is divided into four subspecies, which differ in their virulence and geographic distribution. Two of them, subsp. tularensis (primarily found in North America and subsp. holarctica (widespread across the Northern Hemisphere, are responsible for tularemia in humans. Subsp. novicida is almost avirulent in humans. The fourth subspecies, subsp. mediasiatica, is the least studied because of its limited distribution and impact in human health. It is found only in sparsely populated regions of Central Asia. In this report, we describe the first focus of naturally circulating F. tularensis subsp. mediasiatica in Russia. We isolated and characterized 18 strains of this subspecies in the Altai region. All strains were highly virulent in mice. The virulence of subsp. mediasiatica in a vaccinated mouse model is intermediate between that of subsp. tularensis and subsp. holarctica. Based on a multiple-locus variable number tandem repeat analysis (MLVA, we show that the Altaic population of F. tularensis subsp. mediasiatica is genetically distinct from the classical Central Asian population, and probably is endemic to Southern Siberia. We propose to subdivide the mediasiatica subspecies into three phylogeographic groups, M.I, M.II and M.III.

Proposal to rename Carnobacterium inhibens as Carnobacterium inhibens subsp. inhibens subsp. nov. and description of Carnobacterium inhibens subsp. gilichinskyi subsp. nov., a psychrotolerant bacterium isolated from Siberian permafrost.

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Nicholson, Wayne L; Zhalnina, Kateryna; de Oliveira, Rafael R; Triplett, Eric W

2015-02-01

A novel, psychrotolerant facultative anaerobe, strain WN1359(T), was isolated from a permafrost borehole sample collected at the right bank of the Kolyma River in Siberia, Russia. Gram-positive-staining, non-motile, rod-shaped cells were observed with sizes of 1-2 µm long and 0.4-0.5 µm wide. Growth occurred in the range of pH 5.8-9.0 with optimal growth at pH 7.8-8.6 (pH optimum 8.2). The novel isolate grew at temperatures from 0-37 °C and optimal growth occurred at 25 °C. The novel isolate does not require NaCl; growth was observed between 0 and 8.8 % (1.5 M) NaCl with optimal growth at 0.5 % (w/v) NaCl. The isolate was a catalase-negative, facultatively anaerobic chemo-organoheterotroph that used sugars but not several single amino acids or dipeptides as substrates. The major metabolic end-product was lactic acid in the ratio of 86 % l-lactate : 14 % d-lactate. Strain WN1359(T) was sensitive to ampicillin, chloramphenicol, fusidic acid, lincomycin, monocycline, rifampicin, rifamycin SV, spectinomycin, streptomycin, troleandomycin and vancomycin, and resistant to nalidixic acid and aztreonam. The fatty acid content was predominantly unsaturated (70.2 %), branched-chain unsaturated (11.7 %) and saturated (12.5 %). The DNA G+C content was 35.3 mol% by whole genome sequence analysis. 16S rRNA gene sequence analysis showed 98.7 % sequence identity between strain WN1359(T) and Carnobacterium inhibens. Genome relatedness was computed using both Genome-to-Genome Distance Analysis (GGDA) and Average Nucleotide Identity (ANI), which both strongly supported strain WN1359(T) belonging to the species C. inhibens. On the basis of these results, the permafrost isolate WN1359(T) represents a novel subspecies of C. inhibens, for which the name Carnobacterium inhibens subsp. gilichinskyi subsp. nov. is proposed. The type strain is WN1359(T) ( = ATCC BAA-2557(T) = DSM 27470(T)). The subspecies Carnobacterium inhibens subsp. inhibens subsp. nov. is created automatically. An

Lactobacillus paracasei subsp. paracasei B21060 suppresses human T-cell proliferation.

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Peluso, Ilaria; Fina, Daniele; Caruso, Roberta; Stolfi, Carmine; Caprioli, Flavio; Fantini, Massimo Claudio; Caspani, Giorgio; Grossi, Enzo; Di Iorio, Laura; Paone, Francesco Maria; Pallone, Francesco; Monteleone, Giovanni

2007-04-01

Recent studies have shown that probiotics are beneficial in T-cell-mediated inflammatory diseases. The molecular mechanism by which probiotics work remains elusive, but accumulating evidence indicates that probiotics can modulate immune cell responses. Since T cells express receptors for bacterial products or components, we examined whether different strains of lactobacilli directly regulate the functions of human T cells. CD4(+) T cells were isolated from blood and intestinal lamina propria (LP) of normal individuals and patients with inflammatory bowel disease (IBD). Mononuclear cells were also isolated from Peyer's patches. Cells were activated with anti-CD3/CD2/CD28 in the presence or absence of Lactobacillus paracasei subsp. paracasei B21060, L. paracasei subsp. paracasei F19, or L. casei subsp. casei DG. Cell proliferation and death, Foxp3, intracellular pH, and cytokine production were evaluated by flow cytometry. We showed that L. paracasei subsp. paracasei B21060 but neither L. paracasei subsp. paracasei F19 nor L. casei subsp. casei DG inhibited blood CD4(+) T-cell growth. This effect was associated with no change in cell survival, expression of Foxp3, or production of gamma interferon, interleukin-4 (IL-4), IL-5, and IL-10. L. paracasei subsp. paracasei B21060-mediated blockade of CD4(+) T-cell proliferation required a viable bacterium and was associated with decreased MCT-1 expression and low intracellular pH. L. paracasei subsp. paracasei B21060 also inhibited the growth of Peyer's patch mononuclear cells, normal lymphocytes, and IBD CD4(+) LP lymphocytes without affecting cytokine production. The data show that L. paracasei subsp. paracasei B21060 blocks T-cell growth, thus suggesting a mechanism by which these probiotics could interfere with T-cell-driven immune responses.

Comparative genomics of Lactobacillus and other LAB

DEFF Research Database (Denmark)

Wassenaar, Trudy M.; Lukjancenko, Oksana

2014-01-01

that of the others, with the two Streptococcus species having the shortest genomes. The widest distribution in genome content was observed for Lactobacillus. The number of tRNA and rRNA gene copies varied considerably, with exceptional high numbers observed for Lb. delbrueckii, while these numbers were relatively......The genomes of 66 LABs, belonging to five different genera, were compared for genome size and gene content. The analyzed genomes included 37 Lactobacillus genomes of 17 species, six Lactococcus lactis genomes, four Leuconostoc genomes of three species, six Streptococcus genomes of two species...

Role of Blossoms in Watermelon Seed Infestation by Acidovorax avenae subsp. citrulli.

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Walcott, R R; Gitaitis, R D; Castro, A C

2003-05-01

ABSTRACT The role of watermelon blossom inoculation in seed infestation by Acidovorax avenae subsp. citrulli was investigated. Approximately 98% (84/87) of fruit developed from blossoms inoculated with 1 x 10(7) or 1 x 10(9) CFU of A. avenae subsp. citrulli per blossom were asymptomatic. Using immunomagnetic separation and the polymerase chain reaction, A. avenae subsp. citrulli was detected in 44% of the seed lots assayed, despite the lack of fruit symptoms. Furthermore, viable colonies were recovered from 31% of the seed lots. Of these lots, 27% also yielded seedlings expressing bacterial fruit blotch symptoms when planted under conditions of 30 degrees C and 90% relative humidity. A. avenae subsp. citrulli was detected and recovered from the pulp of 33 and 19%, respectively, of symptomless fruit whose blossoms were inoculated with A. avenae subsp. citrulli. The ability to penetrate watermelon flowers was not unique to A. avenae subsp. citrulli, because blossoms inoculated with Pantoea ananatis also resulted in infested seed and pulp. The data indicate that watermelon blossoms are a potential site of ingress for fruit and seed infestation by A. avenae subsp. citrulli.

Enhanced Microbial, Functional and Sensory Properties of Herbal Yogurt Fermented with Korean Traditional Plant Extracts

Science.gov (United States)

Joung, Jae Yeon; Lee, Ji Young; Ha, Young Sik; Shin, Yong Kook; Kim, Younghoon; Kim, Sae Hun; Oh, Nam Su

2016-01-01

This study evaluated the effects of two Korean traditional plant extracts (Diospyros kaki THUNB. leaf; DK, and Nelumbo nucifera leaf; NN) on the fermentation, functional and sensory properties of herbal yogurts. Compared to control fermentation, all plant extracts increased acidification rate and reduced the time to complete fermentation (pH 4.5). Supplementation of plant extracts and storage time were found to influence the characteristics of the yogurts, contributing to increased viability of starter culture and phenolic compounds. In particular, the increase in the counts of Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus was highest (2.95 and 1.14 Log CFU/mL respectively) in DK yogurt. Furthermore, supplementation of the plant extracts significantly influenced to increase the antioxidant activity and water holding capacity and to produce volatile compounds. The higher antioxidant activity and water holding capacity were observed in NN yogurt than DK yogurt. Moreover, all of the sensory characteristics were altered by the addition of plant extracts. Addition of plant extracts increased the scores related to flavor, taste, and texture from plain yogurt without a plant extract, as a result of volatile compounds analysis. Thus, the overall preference was increased by plant extracts. Consequently, supplementation of DK and NN extracts in yogurt enhanced the antioxidant activity and physical property, moreover increased the acceptability of yogurt. These findings demonstrate the possibility of using plant extracts as a functional ingredient in the manufacture of herbal yogurt. PMID:27499669

Enhanced Microbial, Functional and Sensory Properties of Herbal Yogurt Fermented with Korean Traditional Plant Extracts.

Science.gov (United States)

Joung, Jae Yeon; Lee, Ji Young; Ha, Young Sik; Shin, Yong Kook; Kim, Younghoon; Kim, Sae Hun; Oh, Nam Su

2016-01-01

This study evaluated the effects of two Korean traditional plant extracts (Diospyros kaki THUNB. leaf; DK, and Nelumbo nucifera leaf; NN) on the fermentation, functional and sensory properties of herbal yogurts. Compared to control fermentation, all plant extracts increased acidification rate and reduced the time to complete fermentation (pH 4.5). Supplementation of plant extracts and storage time were found to influence the characteristics of the yogurts, contributing to increased viability of starter culture and phenolic compounds. In particular, the increase in the counts of Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus was highest (2.95 and 1.14 Log CFU/mL respectively) in DK yogurt. Furthermore, supplementation of the plant extracts significantly influenced to increase the antioxidant activity and water holding capacity and to produce volatile compounds. The higher antioxidant activity and water holding capacity were observed in NN yogurt than DK yogurt. Moreover, all of the sensory characteristics were altered by the addition of plant extracts. Addition of plant extracts increased the scores related to flavor, taste, and texture from plain yogurt without a plant extract, as a result of volatile compounds analysis. Thus, the overall preference was increased by plant extracts. Consequently, supplementation of DK and NN extracts in yogurt enhanced the antioxidant activity and physical property, moreover increased the acceptability of yogurt. These findings demonstrate the possibility of using plant extracts as a functional ingredient in the manufacture of herbal yogurt.

Sebze Püresi ile Üretilen Yoğurtların Tekstürel ve Duyusal Özelliklerinin Belirlenmesi

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Tülay Özcan

2016-07-01

Full Text Available Bu çalışmada kontrol (K; balkabağı (YBK, havuç (YHA, bezelye (YBE ve yeşil kabak püreli (YYK yoğurt olmak üzere 5 farklı set tipi yoğurt üretilmiştir. Sebzeli yoğurtlarda bulunan diyet liflerinin bakteri gelişmesini teşvik eden potansiyel etkisi sonucu Streptococcus thermophilus ile Lactobacillus delbrueckii subsp. bulgaricus sayılarının arttığı saptanmıştır. Yoğurtların sebze püreleri ile zenginleştirilmesinin pH, titrasyon asitliği, serum ayrılması, duyusal özelikler ile sertlik, iç yapışkanlık, konsistens ve viskozite indeksi gibi tekstürel özellikler üzerinde etkili olduğu gözlenmiştir. Havuç püresi ile üretilen yoğurtlarda viskozite, konsistens ve sertliğin yüksek olduğu saptanırken, yeşil kabak ilaveli olanlar daha zayıf tekstürel özellikler göstermiştir. Sonuç olarak sebze püresi ilavesinin set tipi yoğurtlarda tekstürel özelliklerinin iyileştirilmesi konusunda önemli rol oynadığı ve fonksiyonel süt ürünlerinin geliştirilmesinde kullanılabileceği belirlenmiştir.

Exploring the Behavior and Metabolic Transformations of SeNPs in Exposed Lactic Acid Bacteria. Effect of Nanoparticles Coating Agent

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Maria Palomo-Siguero

2017-08-01

Full Text Available The behavior and transformation of selenium nanoparticles (SeNPs in living systems such as microorganisms is largely unknown. To address this knowledge gap, we examined the effect of three types of SeNP suspensions toward Lactobacillus delbrueckii subsp. bulgaricus LB-12 using a variety of techniques. SeNPs were synthesized using three types of coating agents (chitosan (CS-SeNPs, hydroxyethyl cellulose (HEC-SeNPs and a non-ionic surfactant, surfynol (ethoxylated-SeNPs. Morphologies of SeNPs were all spherical. Transmission electron microscopy (TEM was used to locate SeNPs in the bacteria. High performance liquid chromatography (HPLC on line coupled to inductively coupled plasma mass spectrometry (ICP-MS was applied to evaluate SeNP transformation by bacteria. Finally, flow cytometry employing the live/dead test and optical density measurements at 600 nm (OD600 were used for evaluating the percentages of bacteria viability when supplementing with SeNPs. Negligible damage was detected by flow cytometry when bacteria were exposed to HEC-SeNPs or CS-SeNPs at a level of 10 μg Se mL−1. In contrast, ethoxylated-SeNPs were found to be the most harmful nanoparticles toward bacteria. CS-SeNPs passed through the membrane without causing damage. Once inside, SeNPs were metabolically transformed to organic selenium compounds. Results evidenced the importance of capping agents when establishing the true behavior of NPs.

Assessing the inactivation of Mycobacterium avium subsp. paratuberculosis during composting of livestock carcasses.

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Tkachuk, Victoria L; Krause, Denis O; McAllister, Tim A; Buckley, Katherine E; Reuter, Tim; Hendrick, Steve; Ominski, Kim H

2013-05-01

Mycobacterium avium subsp. paratuberculosis causes Johne's disease (JD) in ruminants, with substantial economic impacts on the cattle industry. Johne's disease is known for its long latency period, and difficulties in diagnosis are due to insensitivities of current detection methods. Eradication is challenging as M. avium subsp. paratuberculosis can survive for extended periods within the environment, resulting in new infections in naïve animals (W. Xu et al., J. Environ. Qual. 38:437-450, 2009). This study explored the use of a biosecure, static composting structure to inactivate M. avium subsp. paratuberculosis. Mycobacterium smegmatis was also assessed as a surrogate for M. avium subsp. paratuberculosis. Two structures were constructed to hold three cattle carcasses each. Naturally infected tissues and ground beef inoculated with laboratory-cultured M. avium subsp. paratuberculosis and M. smegmatis were placed in nylon and plastic bags to determine effects of temperature and compost environment on viability over 250 days. After removal, samples were cultured and growth of both organisms was assessed after 12 weeks. After 250 days, M. avium subsp. paratuberculosis was still detectable by PCR, while M. smegmatis was not detected after 67 days of composting. Furthermore, M. avium subsp. paratuberculosis remained viable in both implanted nylon and plastic bags over the composting period. As the compost never reached a homogenous thermophilic (55 to 65°C) state throughout each structure, an in vitro experiment was conducted to examine viability of M. avium subsp. paratuberculosis after exposure to 80°C for 90 days. Naturally infected lymph tissues were mixed with and without compost. After 90 days, M. avium subsp. paratuberculosis remained viable despite exposure to temperatures typically higher than that achieved in compost. In conclusion, it is unlikely composting can be used as a means of inactivating M. avium subsp. paratuberculosis associated with cattle

Assessing the Inactivation of Mycobacterium avium subsp. paratuberculosis during Composting of Livestock Carcasses

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Tkachuk, Victoria L.; Krause, Denis O.; McAllister, Tim A.; Buckley, Katherine E.; Reuter, Tim; Hendrick, Steve

2013-01-01

Mycobacterium avium subsp. paratuberculosis causes Johne's disease (JD) in ruminants, with substantial economic impacts on the cattle industry. Johne's disease is known for its long latency period, and difficulties in diagnosis are due to insensitivities of current detection methods. Eradication is challenging as M. avium subsp. paratuberculosis can survive for extended periods within the environment, resulting in new infections in naïve animals (W. Xu et al., J. Environ. Qual. 38:437-450, 2009). This study explored the use of a biosecure, static composting structure to inactivate M. avium subsp. paratuberculosis. Mycobacterium smegmatis was also assessed as a surrogate for M. avium subsp. paratuberculosis. Two structures were constructed to hold three cattle carcasses each. Naturally infected tissues and ground beef inoculated with laboratory-cultured M. avium subsp. paratuberculosis and M. smegmatis were placed in nylon and plastic bags to determine effects of temperature and compost environment on viability over 250 days. After removal, samples were cultured and growth of both organisms was assessed after 12 weeks. After 250 days, M. avium subsp. paratuberculosis was still detectable by PCR, while M. smegmatis was not detected after 67 days of composting. Furthermore, M. avium subsp. paratuberculosis remained viable in both implanted nylon and plastic bags over the composting period. As the compost never reached a homogenous thermophilic (55 to 65°C) state throughout each structure, an in vitro experiment was conducted to examine viability of M. avium subsp. paratuberculosis after exposure to 80°C for 90 days. Naturally infected lymph tissues were mixed with and without compost. After 90 days, M. avium subsp. paratuberculosis remained viable despite exposure to temperatures typically higher than that achieved in compost. In conclusion, it is unlikely composting can be used as a means of inactivating M. avium subsp. paratuberculosis associated with cattle

Environmental Mycobacterium avium subsp. paratuberculosis hosted by free-living amoebae

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Mycobacterium avium subsp. paratuberculosis is responsible for paratuberculosis in animals. This disease, leading to an inflammation of the gastrointestinal tract, has a high impact on animal health and an important economic burden. The environmental life cycle of Mycobacterium avium subsp. paratube...

Relationship between presence of cows with milk positive for Mycobacterium avium subsp. paratuberculosis-specific antibody by enzyme-linked immunosorbent assay and viable M. avium subsp. paratuberculosis in dust in cattle barns.

Science.gov (United States)

Eisenberg, Susanne W F; Chuchaisangrat, Ruj; Nielen, Mirjam; Koets, Ad P

2013-09-01

Paratuberculosis, or Johne's disease, in cattle is caused by Mycobacterium avium subsp. paratuberculosis, which has recently been suspected to be transmitted through dust. This longitudinal study on eight commercial M. avium subsp. paratuberculosis-positive dairy farms studied the relationship between the number of cows with M. avium subsp. paratuberculosis antibody-positive milk and the presence of viable M. avium subsp. paratuberculosis in settled-dust samples, including their temporal relationship. Milk and dust samples were collected in parallel monthly for 2 years. M. avium subsp. paratuberculosis antibodies in milk were measured by enzyme-linked immunosorbent assay (ELISA) and used as a proxy for M. avium subsp. paratuberculosis shedding. Settled-dust samples were collected by using electrostatic dust collectors (EDCs) at six locations in housing for dairy cattle and young stock. The presence of viable M. avium subsp. paratuberculosis was identified by liquid culture and PCR. The results showed a positive relationship (odds ratio [OR], 1.2) between the number of cows with ELISA-positive milk and the odds of having positive EDCs in the same airspace as the adult dairy cattle. Moreover, the total number of lactating cows also showed an OR slightly above 1. This relationship remained the same for settled-dust samples collected up to 2 months before or after the time of milk sampling. The results suggest that removal of adult cows with milk positive for M. avium subsp. paratuberculosis-specific antibody by ELISA might result in a decrease in the presence of viable M. avium subsp. paratuberculosis in dust and therefore in the environment. However, this decrease is likely delayed by several weeks at least. In addition, the data support the notion that M. avium subsp. paratuberculosis exposure of young stock is reduced by separate housing.

Thermal Inactivation of Mycobacterium avium subsp. paratuberculosis in Artificially Contaminated Milk by Direct Steam Injection

Science.gov (United States)

Butot, Sophie; Jagadeesan, Balamurugan; Bakker, Douwe; Donaghy, John

2016-01-01

ABSTRACT The efficiency of direct steam injection (DSI) at 105°C for 3 s to inactivate Mycobacterium avium subsp. paratuberculosis in milk at a pilot-plant scale was investigated. Milk samples were artificially contaminated with M. avium subsp. paratuberculosis and also with cow fecal material naturally infected with M. avium subsp. paratuberculosis. We also tested milk artificially contaminated with Mycobacterium smegmatis as a candidate surrogate to compare thermal inactivation between M. smegmatis and M. avium subsp. paratuberculosis. Following the DSI process, no viable M. avium subsp. paratuberculosis or M. smegmatis was recovered using culture methods for both strains. For pure M. avium subsp. paratuberculosis cultures, a minimum reduction of 5.6 log10 was achieved with DSI, and a minimum reduction of 5.7 log10 was found with M. smegmatis. The minimum log10 reduction for wild-type M. avium subsp. paratuberculosis naturally present in feces was 3.3. In addition, 44 dairy and nondairy powdered infant formula (PIF) ingredients used during the manufacturing process of PIF were tested for an alternate source for M. avium subsp. paratuberculosis and were found to be negative by quantitative PCR (qPCR). In conclusion, the results obtained from this study indicate that a >7-fold-log10 reduction of M. avium subsp. paratuberculosis in milk can be achieved with the applied DSI process. IMPORTANCE M. avium subsp. paratuberculosis is widespread in dairy herds in many countries. M. avium subsp. paratuberculosis is the causative agent of Johne's disease in cattle, and infected animals can directly or indirectly (i.e., fecal contamination) contaminate milk. Despite much research and debate, there is no conclusive evidence that M. avium subsp. paratuberculosis is a zoonotic bacterium, i.e., one that causes disease in humans. The presence of M. avium subsp. paratuberculosis or its DNA has been reported in dairy products, including pasteurized milk, cheese, and infant formula

Isolation and characterisation of new putative probiotic bacteria from human colonic flora.

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Raz, Irit; Gollop, Natan; Polak-Charcon, Sylvie; Schwartz, Betty

2007-04-01

The present study describes a novel bacterial isolate exhibiting high ability to synthesise and secrete butyrate. The novel isolated bacterium was obtained from human faeces and grown in selective liquid intestinal microflora medium containing rumen fluid under microaerobic conditions. Its probiotic properties were demonstrated by the ability of the isolate to survive high acidity and medium containing bile acids and the ability to adhere to colon cancer cells (Caco-2) in vitro. Phylogenetic identity to Enterococcus durans was established using specific primers for 16S rRNA (99% probability). PCR analyses with primers to the bacterial gene encoding butyrate kinase, present in the butyrogenic bacteria Clostridium, showed that this gene is present in E. durans. The in vivo immunoprotective and anti-inflammatory effects of E. durans were assessed in dextran sodium sulfate (DSS)-induced colitis in Balb/c mice. Administration of E. durans ameliorated histological, clinical and biochemical scores directly related to intestinal inflammation whereas the lactic acid bacterium Lactobacillus delbrueckii was ineffective in this regard. Colonic cDNA concentrations of IL-1beta and TNF-alpha were significantly down regulated in DSS-treated E. durans-fed mice but not in control or DSS-treated L. delbrueckii- fed mice. Fluorescent in situ hybridisation analyses of colonic tissue from mice fed E. durans, using a butyrate kinase probe, demonstrated that E. durans significantly adheres to the colonic tissue. The novel isolated bacterium described in the present paper, upon further characterisation, can be developed into a useful probiotic aimed at the treatment of patients suffering from ulcerative colitis.

Impact of oxygenation on the performance of three non-Saccharomyces yeasts in co-fermentation with Saccharomyces cerevisiae.

Science.gov (United States)

Shekhawat, Kirti; Bauer, Florian F; Setati, Mathabatha E

2017-03-01

The sequential or co-inoculation of grape must with non-Saccharomyces yeast species and Saccharomyces cerevisiae wine yeast strains has recently become a common practice in winemaking. The procedure intends to enhance unique aroma and flavor profiles of wine. The extent of the impact of non-Saccharomyces strains depends on their ability to produce biomass and to remain metabolically active for a sufficiently long period. However, mixed-culture wine fermentations tend to become rapidly dominated by S. cerevisiae, reducing or eliminating the non-Saccharomyces yeast contribution. For an efficient application of these yeasts, it is therefore essential to understand the environmental factors that modulate the population dynamics of such ecosystems. Several environmental parameters have been shown to influence population dynamics, but their specific effect remains largely uncharacterized. In this study, the population dynamics in co-fermentations of S. cerevisiae and three non-Saccharomyces yeast species: Torulaspora delbrueckii, Lachancea thermotolerans, and Metschnikowia pulcherrima, was investigated as a function of oxygen availability. In all cases, oxygen availability strongly influenced population dynamics, but clear species-dependent differences were observed. Our data show that L. thermotolerans required the least oxygen, followed by T. delbrueckii and M. pulcherrima. Distinct species-specific chemical volatile profiles correlated in all cases with increased persistence of non-Saccharomyces yeasts, in particular increases in some higher alcohols and medium chain fatty acids. The results highlight the role of oxygen in regulating the succession of yeasts during wine fermentations and suggests that more stringent aeration strategies would be necessary to support the persistence of non-Saccharomyces yeasts in real must fermentations.

VIABILIDADE DE BACTÉRIAS ÁCIDO LÁTICAS EM SORVETES DE IOGURTE DURANTE O PERÍODO DE ESTOCAGEM

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Daniela Peres MIGUEL

2009-07-01

Full Text Available

Recentemente, o mercado colocou à disposição dos consumidores uma nova versão de iogurte: o frozen yogurt, obtido a partir do iogurte tradicional, no qual as bactérias ácido láticas permanecem viáveis até o momento do consumo. Esse produto tornou-se popular entre adultos devido ao seu potencial em exercer efeitos benéficos à saúde. O objetivo deste trabalho foi verificar a viabilidade de bactérias ácido láticas em sorvetes de iogurte armazenados a -23ºC durante um período de seis meses de estocagem. As amostras de sorvetes de iogurte foram processadas a partir dos seguintes tipos de iogurte: (1 iogurte convencional (leite de vaca fermentado com L. delbrueckii ssp. bulgaricus e S. thermophillus; (2 "iogurte" soja, fermentado com cultivo misto de Lactobacillus delbrueckii ssp. bulgaricus e Streptococcus thermophillus; (3 "iogurte" de soja, utilizando como inóculo um cultivo misto de Lactobacillus jugurti e Enterococcus faecium, este último com capacidade hipocolesterolêmica já demonstrada em ensaios "in vitro" e "in vivo" (cultura probiótica. Todos os produtos foram processados em 3 ocasiões distintas. Os resultados demonstraram que os produtos fermentados, tanto com culturas probióticas quanto convencionais, apresentaram contagens de células viáveis superiores a 106 UFC/ml ao longo do período de estocagem. PALAVRAS-CHAVE: Sorvete; iogurte; probiótico; bactérias ácido láticas; E. faecium.

Antioxidant activity profiling by spectrophotometric methods of aqueous methanolic extracts of Helichrysum stoechas subsp. rupestre and Phagnalon saxatile subsp. saxatile.

Science.gov (United States)

Haddouchi, Farah; Chaouche, Tarik Mohammed; Ksouri, Riadh; Medini, Faten; Sekkal, Fatima Zohra; Benmansour, Abdelhafid

2014-06-01

The aqueous methanolic extracts of two plants from Algeria, Helichrysum stoechas subsp. rupestre and Phagnalon saxatile subsp. saxatile, were investigated for their antioxidant activity. Total phenolics, flavonoids, and tannins were determined by spectrophotometric techniques. In vitro antioxidant and radical scavenging profiling was determined by spectrophotometric methods, through: Total antioxidant capacity, and radical scavenging effects by the DPPH and ABTS methods, reducing and chelating power, and blanching inhibition of the β-carotene. All of the extracts showed interesting antioxidant and radical scavenging activity. The highest contents in phenolics, tannins, and the highest total antioxidant capacity as gallic acid equivalents of 97.5 ± 0.33 mg GAE/g DW was obtained for the flowers of H. stoechas subsp. rupestre extract in the phosphomolybdenum assay. An extract of the leafy stems of P. saxatile subsp. saxatile revealed the highest content of flavonoids, and the highest antioxidant activity by the radical scavenging and β-carotene assays when compared with standards. The best activity was by the scavenging radical DPPH with an IC50 value of 5.65 ± 0.10 μg·mL(-1). The studied medicinal plants could provide scientific evidence for some traditional uses in the treatment of diseases related to the production of reactive oxygen species (ROS) and oxidative stress. Copyright © 2014 China Pharmaceutical University. Published by Elsevier B.V. All rights reserved.

Structural studies of exopolysaccharides produced by Lactobacillus delbrueckii ssp. bulgaricus

NARCIS (Netherlands)

Sanchez de Medina Herrera, I.M.

2007-01-01

Exopolysaccharides (EPSs) produced by lactic acid bacteria are widely used in the food industry, especially for the preparation of dairy products, such as yoghurt and cheese. Their interesting physical and rheological properties make them suitable as gellifying or viscosifying agents in the

Probiotic Yoghurts From Ultrafiltered Concentrated Milk

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Kozludzhova Siyka

2015-12-01

Full Text Available In this paper, yoghurts from ultrafiltered concentrated whole milk with a volume reduction ratio 0, 2 and 3 with three different probiotic yoghurt starters were obtained. Their physiological, microbiological and rheological properties were examined. The concentrated probiotic yoghurts had high concentration of viable cells of the probiotic strain Lactobacillus delbrueckii ssp. bulgaricus (over 1010cfu/cm3. For the preparation of concentrated probiotic yoghurts the most appropriate volume reduction ratio was 2. The probiotic yoghurts with starters MZ2 and 1CM had the best structure. The concentrated probiotic yoghurts with all starters are functional foods.

of gastro-intestinal discomfort (ID 2946, 2951, 2974), decreasing potentially pathogenic gastro-intestinal microorganisms (ID 2946, 2951, 2974), improved lactose digestion (ID 2946, 2951, 2974), and reduction in numbers of circulating CD34+ cells (ID 2947, 2952, 2975) (further assessment) pursuant

DEFF Research Database (Denmark)

Tetens, Inge

of Lactobacillus acidophilus BCCM/LMG P-18806, Lactobacillus delbrueckii BCCM/LMG P-18805 and Streptococcus thermophilus BCCM/LMG P-18807 and reduction of gastro-intestinal discomfort, decreasing potentially pathogenic gastro-intestinal microorganisms, improved lactose digestion, and reduction in numbers......, might be a beneficial physiological effect for the general population. The claimed effect, improved lactose digestion, is a beneficial physiological effect for individuals with lactose maldigestion. No human intervention studies were provided from which conclusions could be drawn for the scientific...... and reduction of gastro-intestinal discomfort, decreasing potentially pathogenic gastro-intestinal microorganisms, and improved lactose digestion....

Effects of yogurt starter cultures on the survival of Lactobacillus acidophilus.

Science.gov (United States)

Ng, Elizabeth W; Yeung, Marie; Tong, Phillip S

2011-01-31

Recognized to confer health benefits to consumers, probiotics such as Lactobacillus acidophilus are commonly incorporated into fermented dairy products worldwide; among which yogurt is a popular delivery vehicle. To materialize most of the putative health benefits associated with probiotics, an adequate amount of viable cells must be delivered at the time of consumption. However, the loss in their viabilities during refrigerated storage has been demonstrated previously. This study focused on the effects of yogurt starter cultures on the survival of five strains of L. acidophilus, with emphases on low pH and acid production. Differential survival behavior between L. acidophilus strains was further analyzed. To this end, viable cell counts of L. acidophilus were determined weekly during 4°C storage in various types of yogurts made with Streptococcus thermophilus alone, L. delbrueckii ssp. bulgaricus alone, both species of the starter cultures, or glucono-delta-lactone (GDL). All yogurt types, except for pasteurized yogurts, were co-fermented with L. acidophilus. Yogurt filtrate was analyzed for the presence of any inhibitory substance and for the amount of hydrogen peroxide. Multiplication of L. acidophilus was not affected by the starter cultures as all strains reached high level on day 0 of the storage period. Throughout the 28-day storage period, cell counts of L. acidophilus PIM703 and SBT2062 remained steady (~6 × 10(7)CFU/g) in yogurts made with both starter cultures, whereas those of ATCC 700396 and NCFM were reduced by a maximum of 3 and 4.6 logs, respectively. When starter cultures were replaced by GDL, all strains survived well, suggesting that a low pH was not a critical factor dictating their survival. In addition, the filtrate collected from yogurts made with starter cultures appeared to have higher inhibitory activities against L. acidophilus than that made with GDL. The presence of viable starter cultures was necessary to adversely affect the

Bioaccessible peptides released by in vitro gastrointestinal digestion of fermented goat milks.

Science.gov (United States)

Moreno-Montoro, Miriam; Jauregi, Paula; Navarro-Alarcón, Miguel; Olalla-Herrera, Manuel; Giménez-Martínez, Rafael; Amigo, Lourdes; Miralles, Beatriz

2018-06-01

In this study, ultrafiltered goat milks fermented with the classical starter bacteria Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus salivarus subsp. thermophilus or with the classical starter plus the Lactobacillus plantarum C4 probiotic strain were analyzed using ultra-high performance liquid chromatography-quadrupole-time-of-flight tandem mass spectrometry (UPLC-Q-TOF-MS/MS) and/or high performance liquid chromatography-ion trap (HPLC-IT-MS/MS). Partial overlapping of the identified sequences with regard to fermentation culture was observed. Evaluation of the cleavage specificity suggested a lower proteolytic activity of the probiotic strain. Some of the potentially identified peptides had been previously reported as angiotensin-converting enzyme (ACE) inhibitory, antioxidant, and antibacterial and might account for the in vitro activity previously reported for these fermented milks. Simulated digestion of the products was conducted in the presence of a dialysis membrane to retrieve the bioaccessible peptide fraction. Some sequences with reported physiological activity resisted digestion but were found in the non-dialyzable fraction. However, new forms released by digestion, such as the antioxidant α s1 -casein 144 YFYPQL 149 , the antihypertensive α s2 -casein 90 YQKFPQY 96 , and the antibacterial α s2 -casein 165 LKKISQ 170 , were found in the dialyzable fraction of both fermented milks. Moreover, in the fermented milk including the probiotic strain, the k-casein dipeptidyl peptidase IV inhibitor (DPP-IV) 51 INNQFLPYPY 60 as well as additional ACE inhibitory or antioxidant sequences could be identified. With the aim of anticipating further biological outcomes, quantitative structure activity relationship (QSAR) analysis was applied to the bioaccessible fragments and led to potential ACE inhibitory sequences being proposed. Graphical abstract Ultrafiltered goat milks were fermented with the classical starter bacteria (St) and with St plus the

The effect of disinfectants on Clavibacter michiganensis subsp. sepedonicus and Erwinia carotovora subsp. atroseptica on different surface materials

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Hilkka Koponen

1992-12-01

Full Text Available The effect of seven disinfectants on Clavibacter michiganensis subsp. sepedonicus and Erwinia carotovora subsp. atroseptica was tested on metal, plastic and wood surfaces in laboratory trials. lobac P was the most effective disinfectant in the control of E. carotovora on clean and dirty surfaces. Ipasept and Menno-Ter-forte were effective on plastic surfaces, but dirt reduced their efficacy. The least effective preparations were Deskem-1, Virkon S and Korsolin. lobac P, Korsolin and Virkon S were the most effective disinfectants against C. michiganensis. The efficacy of Ipasept and Menno-Ter-forte was reduced by dirt. The least effective preparation was Deskem-1.

Mycobacterium avium subsp. paratuberculosis: presencia en los alimentos y su relación con la enfermedad de Crohn Mycobacterium avium subsp. paratuberculosis in food and its relationship with Crohn's disease

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K. Cirone

2007-03-01

Full Text Available La paratuberculosis o enfermedad de Johne es una enteritis crónica producida por Mycobacterium avium subsp. paratuberculosis, que afecta a bovinos y a otras especies. En la Argentina se ha caracterizado en rodeos bovinos y de ciervos, con aislamientos tipificados en distintos patrones genéticos. M. avium subsp. paratuberculosis ha sido vinculado en humanos con una inflamación crónica del intestino, denominada enfermedad de Crohn. Existen evidencias clínicas y experimentales que relacionan a M. avium subsp. paratuberculosis con la enfermedad en el humano, mediante su detección por PCR y por cultivo a partir de biopsias de órganos, de leche materna y de sangre de pacientes afectados. La leche y sus subproductos serían posibles fuentes de infección y se ha sugerido que M. avium subsp. paratuberculosis resistiría las condiciones de pasteurización. Diversos trabajos de investigación demostraron que esta micobacteria podría estar presente en leches comercializadas en diversos países, como Reino Unido, Estados Unidos, República Checa, y también en la Argentina. La presencia de M. avium subsp. paratuberculosis en productos lácteos y agua de consumo ha sido relacionada con la resistencia del microorganismo tanto a los procesos de elaboración como a los factores climáticos adversos, lo que enfatiza el rol de los alimentos y del agua como vías de transmisión al humano. Las investigaciones en curso podrían ratificar el riesgo y las implicancias de la exposición del humano a M. avium subsp. paratuberculosis a través de los alimentos y del agua contaminados, para determinar la importancia de la paratuberculosis como enfermedad zoonótica.Paratuberculosis or Johne's disease is a chronic enteritis of the cattle and other small ruminant animals caused by Mycobacterium avium subsp. paratuberculosis. In Argentina, the strains were characterized in beef and dairy cattle and deer in different genetic patterns by molecular tools. M. avium

Technological and Genomic Analysis of Roles of the Cell-Envelope Protease PrtS in Yoghurt Starter Development

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Hui Tian

2018-04-01

Full Text Available The cell-envelope protease PrtS was proved to be efficient in optimal bacterial growth and fast acidification in pure culture, while its positive effect on the performance of mixed-cultures in milk fermentation was not defined. The aim was to analyze effects of the PrtS on the symbiosis between strains during yoghurt production and cold storage. Two Streptococcus thermophilus strains, KLDS3.1012 and KLDS SM, and two different proteolytic strains of Lactobacillus delbrueckii subsp. Bulgaricus, L7 and L12, were used. Technological properties (viability, acid production, and proteolysis were determined. Comparative genomics was used to analyze the proteolytic system (cell-envelope protease, transport system, intracellular peptidase of Streptococcus thermophilus strains. S. thermophilus KLDS SM possesses an intact gene encoding PrtS (A9497_00420, which was not found in the genome of S. thermophilus KLDS3.1012. This gene is the main difference in the proteolytic system between the two genomes. PrtS endowed KLDS SM high levels of viability during fermentation and cold storage. When combined with a weaker lactobacillus strain during fermentation, the acceleration of acid production of mixed-culture by KLDS SM would start at an earlier time. KLDS SM increased the post-acidification of yoghurts during cold storage, but the pH was steadily maintained during 14–28 days. Results suggest that strains of Streptococcus thermophilus with strong proteolytic ability could be used in a wide range of dairy production. The present study provided data for yoghurt starter development from the point of view of proteolysis.

Influence of Spirulina platensis powder on the microflora of yoghurt and acidophilus milk

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Metin Guldas

2010-12-01

Full Text Available The main purpose of this research was to monitor the influence of the powdered Cyanobacterium Spirulina platensis addition to plain yoghurt and the yoghurt containing Lactobacillus acidophiluson survival of the microbiota during the refrigerated storage. The cell viability of yoghurt starter cultures (Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus and Lactobacillus acidophilus under refrigeration conditions in yoghurts prepared with (0.5 or 1.0 (w/w % and without the addition of Spirulina powder was investigated. The yoghurts were prepared under hygienic laboratory conditions and their pH and acidity were controlled during the process. The samples of yoghurts were stored at 4 °C and investigated on days 1, 5, 10, 15, 20, 25 and 30. Viable counts of the lactic acid bacteria were above 6 cfu g-1of all “spirulina powder” added samples whereas control yoghurt samples contained lower lactic acid bacteria count at the end of the storage period. Addition of 1 % Spirulina platensis powder into the yoghurts did not cause significant differences on the viable lactic acid bacteria (p≤0.05. The results showed the positive effect of S. platensis powder on the survival of the lactic acid bacteria during storage of yoghurt (P≤0.05. The sensory analysis was also performed for the yoghurt samples. Sensory scores of 0.5 % spirulina powder added yoghurt samples were better than 1 % spirulina powder added ones. It was determined that spirulina powder added yoghurt is a good medium of lactic acid bacteria during the 30 days of refrigerated storage.

DİYET ACIDOPHILUS BIFIDUS YOĞURDU VE DİYET YOĞURDUN KALİTE NİTELİKLERİNİN İNCELENMESİ

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Oğuz GÜRSOY

1999-03-01

Full Text Available Bu araştırmada, yağ oranı % 1'in altına düşürülmüş sütten; normal yoğurt bakterileri (Streptococcus thermophilus ve Lactobacillus delbrueckii subsp. bulgaricus kullanılarak diyet yoğurt ve yoğurt bakterilerinin yanı sıra Lactobacillus acidophilus ve Bifidobakterileri içeren freeze dried DVS bakteri kültürü kullanılarak diyet Asidofilus bifudus yoğurdu üretilmiş, bu ürünlerin kimyasal, mikrobiyolojik ve duyusal özellikleri karşılaştırmalı olarak incelenmiştir. Genel olarak diyet yoğurt ile diyet Asidofilus bifidus yoğurdunun ağızda hissedilen kıvam dışındaki duyusal özellikleriyle, kimyasal ve mikrobiyolojik özellikleri yönünden birbirine benzer ürünler oldukları tespit edilmiştir. Sonuç olarak bu ürünlerin, normal yoğurt ve yoğurt benzeri ürünlere göre yağ oranlarının düşük olması yanında diyet Asidofilus bifidus yoğurdunda kullanılan kültürün dietetik ve terapötik etkisinden dolayı daha sağlıklı olabilecekleri kanısına varılmıştır.

High quality draft genome sequence of Staphylococcus cohnii subsp. cohnii strain hu-01

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Hu, XinJun; Li, Ang; Lv, LongXian; Yuan, Chunhui; Guo, Lihua; Jiang, Xiawei; Jiang, Haiyin; Qian, GuiRong; Zheng, BeiWen; Guo, Jing; Li, LanJuan

2014-01-01

Staphylococcus cohnii subsp. cohnii belongs to the family Staphylococcaceae in the order Bacillales , class Bacilli and phylum Firmicutes . The increasing relevance of S. cohnii to human health prompted us to determine the genomic sequence of Staphylococcus cohnii subsp. cohnii strain hu-01, a multidrug-resistant isolate from a hospital in China. Here we describe the features of S. cohnii subsp. cohnii strain hu-01, together with the genome sequence and its annotation. This is the first genom...

Diversity, dynamics, and activity of bacterial communities during production of an artisanal Sicilian cheese as evaluated by 16S rRNA analysis.

Science.gov (United States)

Randazzo, Cinzia L; Torriani, Sandra; Akkermans, Antoon D L; de Vos, Willem M; Vaughan, Elaine E

2002-04-01

The diversity and dynamics of the microbial communities during the manufacturing of Ragusano cheese, an artisanal cheese produced in Sicily (Italy), were investigated by a combination of classical and culture-independent approaches. The latter included PCR, reverse transcriptase-PCR (RT-PCR), and denaturing gradient gel electrophoresis (DGGE) of 16S rRNA genes (rDNA). Bacterial and Lactobacillus group-specific primers were used to amplify the V6 to V8 and V1 to V3 regions of the 16S rRNA gene, respectively. DGGE profiles from samples taken during cheese production indicated dramatic shifts in the microbial community structure. Cloning and sequencing of rDNA amplicons revealed that mesophilic lactic acid bacteria (LAB), including species of Leuconostoc, Lactococcus lactis, and Macrococcus caseolyticus were dominant in the raw milk, while Streptococcus thermophilus prevailed during lactic fermentation. Other thermophilic LAB, especially Lactobacillus delbrueckii and Lactobacillus fermentum, also flourished during ripening. Comparison of the rRNA-derived patterns obtained by RT-PCR to the rDNA DGGE patterns indicated a substantially different degree of metabolic activity for the microbial groups detected. Identification of cultivated LAB isolates by phenotypic characterization and 16S rDNA analysis indicated a variety of species, reflecting to a large extent the results obtained from the 16S rDNA clone libraries, with the significant exception of the Lactobacillus delbrueckii species, which dominated in the ripening cheese but was not detected by cultivation. The present molecular approaches combined with culture can effectively describe the complex ecosystem of natural fermented dairy products, giving useful information for starter culture design and preservation of artisanal fermented food technology.

Lactobacillus fermentum ATCC 23271 Displays In vitro Inhibitory Activities against Candida spp.

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do Carmo, Monique S.; Noronha, Francisca M. F.; Arruda, Mariana O.; Costa, Ênnio P. da Silva; Bomfim, Maria R. Q.; Monteiro, Andrea S.; Ferro, Thiago A. F.; Fernandes, Elizabeth S.; Girón, Jorge A.; Monteiro-Neto, Valério

2016-01-01

Lactobacilli are involved in the microbial homeostasis in the female genital tract. Due to the high prevalence of many bacterial diseases of the female genital tract and the resistance of microorganisms to various antimicrobial agents, alternative means to control these infections are necessary. Thus, this study aimed to evaluate the probiotic properties of well-characterized Lactobacillus species, including L. acidophilus (ATCC 4356), L. brevis (ATCC 367), L. delbrueckii ssp. delbrueckii (ATCC 9645), L. fermentum (ATCC 23271), L. paracasei (ATCC 335), L. plantarum (ATCC 8014), and L. rhamnosus (ATCC 9595), against Candida albicans (ATCC 18804), Neisseria gonorrhoeae (ATCC 9826), and Streptococcus agalactiae (ATCC 13813). The probiotic potential was investigated by using the following criteria: (i) adhesion to host epithelial cells and mucus, (ii) biofilm formation, (iii) co-aggregation with bacterial pathogens, (iv) inhibition of pathogen adhesion to mucus and HeLa cells, and (v) antimicrobial activity. Tested lactobacilli adhered to mucin, co-aggregated with all genital microorganisms, and displayed antimicrobial activity. With the exception of L. acidophilus and L. paracasei, they adhered to HeLa cells. However, only L. fermentum produced a moderate biofilm and a higher level of co-aggregation and mucin binding. The displacement assay demonstrated that all Lactobacillus strains inhibit C. albicans binding to mucin (p < 0.001), likely due to the production of substances with antimicrobial activity. Clinical isolates belonging to the most common Candida species associated to vaginal candidiasis were inhibited by L. fermentum. Collectively, our data suggest that L. fermentum ATCC 23271 is a potential probiotic candidate, particularly to complement candidiasis treatment, since presented with the best probiotic profile in comparison with the other tested lactobacilli strains. PMID:27833605

Lactobacillus fermentum ATCC 23271 displays in vitro inhibitory activities against Candida spp.

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Monique Santos Carmo

2016-10-01

Full Text Available Lactobacilli are involved in the microbial homeostasis in the female genital tract. Due to the high prevalence of many bacterial diseases of the female genital tract and the resistance of microorganisms to various antimicrobial agents, alternative means to control these infections are necessary. Thus, this study aimed to evaluate the probiotic properties of well-characterized Lactobacillus species, including L. acidophilus (ATCC 4356, L. brevis (ATCC 367, L. delbrueckii ssp. delbrueckii (ATCC 9645, L. fermentum (ATCC 23271, L. paracasei (ATCC 335, L. plantarum (ATCC 8014, and L. rhamnosus (ATCC 9595, against Candida albicans (ATCC 18804, Neisseria gonorrhoeae (ATCC 9826, and Streptococcus agalactiae (ATCC 13813. The probiotic potential was investigated by using the following criteria: i adhesion to host epithelial cells and mucus, ii biofilm formation, iii co-aggregation with bacterial pathogens, iv inhibition of pathogen adhesion to mucus and HeLa cells, and v antimicrobial activity. Tested lactobacilli adhered to mucin, co-aggregated with all genital microorganisms, and displayed antimicrobial activity. With the exception of L. acidophilus and L. paracasei, they adhered to HeLa cells. However, only L. fermentum produced a moderate biofilm and a higher level of co-aggregation and mucin binding. The displacement assay demonstrated that all Lactobacillus strains inhibit C. albicans binding to mucin (p < 0.001, likely due to the production of substances with antimicrobial activity. Clinical isolates belonging to the most common Candida species associated to vaginal candidosis were inhibited by L. fermentum. Collectively, our data suggest that L. fermentum ATCC 23271 is a potential probiotic candidate, particularly to complement candidosis treatment, since presented with the best probiotic profile in comparison with the other tested lactobacilli strains.

Yeast-yeast interactions revealed by aromatic profile analysis of Sauvignon Blanc wine fermented by single or co-culture of non-Saccharomyces and Saccharomyces yeasts.

Science.gov (United States)

Sadoudi, Mohand; Tourdot-Maréchal, Raphaëlle; Rousseaux, Sandrine; Steyer, Damien; Gallardo-Chacón, Joan-Josep; Ballester, Jordi; Vichi, Stefania; Guérin-Schneider, Rémi; Caixach, Josep; Alexandre, Hervé

2012-12-01

There has been increasing interest in the use of selected non-Saccharomyces yeasts in co-culture with Saccharomyces cerevisiae. The main reason is that the multistarter fermentation process is thought to simulate indigenous fermentation, thus increasing wine aroma complexity while avoiding the risks linked to natural fermentation. However, multistarter fermentation is characterised by complex and largely unknown interactions between yeasts. Consequently the resulting wine quality is rather unpredictable. In order to better understand the interactions that take place between non-Saccharomyces and Saccharomyces yeasts during alcoholic fermentation, we analysed the volatile profiles of several mono-culture and co-cultures. Candida zemplinina, Torulaspora delbrueckii and Metschnikowia pulcherrima were used to conduct fermentations either in mono-culture or in co-culture with S. cerevisiae. Up to 48 volatile compounds belonging to different chemical families were quantified. For the first time, we show that C. zemplinina is a strong producer of terpenes and lactones. We demonstrate by means of multivariate analysis that different interactions exist between the co-cultures studied. We observed a synergistic effect on aromatic compound production when M. pulcherrima was in co-culture with S. cerevisiae. However a negative interaction was observed between C. zemplinina and S. cerevisiae, which resulted in a decrease in terpene and lactone content. These interactions are independent of biomass production. The aromatic profiles of T. delbrueckii and S. cerevisiae in mono-culture and in co-culture are very close, and are biomass-dependent, reflecting a neutral interaction. This study reveals that a whole family of compounds could be altered by such interactions. These results suggest that the entire metabolic pathway is affected by these interactions. Copyright © 2012 Elsevier Ltd. All rights reserved.

Tulum Peynirlerinden izole Edilen Lactococcus lactis subsp. lactis YBML9 ve

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Yasin TUNCER

2009-04-01

Full Text Available Bu çalısmanın amacı tulum peynirlerinden izole edilen Lactococcus lactis suslarının fenotipik tanısı ve bu suslar tarafından üretilen bakteriyosinlerin kısmi karakterizasyonlarıdır. Bu amaçla Türkiye'nin sekiz farklı ilinden (Ankara, Antalya, Burdur, Denizli, Erzincan, Isparta, İstanbul ve İzmir yöresel pazarlardan toplanan 60 adet tulum peyniri örneginden 40 adet Lactococcus lactis susu (31 adet L. lactis subsp. lactis ve 9 adet L. lactis subsp. cremoris izole edildi. 40 adet L. lactis susu içerisinden, 2 adet L. lactis subsp. lactis (YBML9 ve YBML21 susu bakteriyosin üretme yeteneginde bulundu. L. lactis subsp. lactis YBML9 ve YBML21 susları tarafından üretilen bakteriyosinler, farklı enzim, pH ve sıcaklık uygulamaları sonucu; sırasıyla nisin ve laktisin 481 olarak tanımlandı.

High quality draft genome sequence of Staphylococcus cohnii subsp. cohnii strain hu-01.

Science.gov (United States)

Hu, XinJun; Li, Ang; Lv, LongXian; Yuan, Chunhui; Guo, Lihua; Jiang, Xiawei; Jiang, Haiyin; Qian, GuiRong; Zheng, BeiWen; Guo, Jing; Li, LanJuan

2014-06-15

Staphylococcus cohnii subsp. cohnii belongs to the family Staphylococcaceae in the order Bacillales, class Bacilli and phylum Firmicutes. The increasing relevance of S. cohnii to human health prompted us to determine the genomic sequence of Staphylococcus cohnii subsp. cohnii strain hu-01, a multidrug-resistant isolate from a hospital in China. Here we describe the features of S. cohnii subsp. cohnii strain hu-01, together with the genome sequence and its annotation. This is the first genome sequence of the species Staphylococcus cohnii.

Antimicrobial susceptibility of microflora from ovine cheese.

Science.gov (United States)

Kmeť, V; Drugdová, Z

2012-07-01

Strains identified in ovine cheese and bryndza by matrix-assisted laser desorption/ionization time-of-flight analysis belonged to ten species of non-enterococcal lactic acid bacteria and included Lactobacillus casei/Lactobacillus paracasei, Lactobacillus plantarum, Lactobacillus rhamnosus, Lactobacillus helveticus, Lactobacillus delbrueckii, Lactobacillus fermentum, Lactobacillus brevis, Lactococcus lactis, Pediococcus pentosaceus and Pediococcus acidilactici. The susceptibility toward antibiotics was determined in lactobacilli, lactococci and pediococci and also in Escherichia coli for comparison. Analysis of L. fermentum and pediococci revealed the presence of non-wild-type epidemiological cut-offs in streptomycin, clindamycin or gentamicin. E. coli were resistant to ampicillin, tetracycline, enrofloxacin and florfenicol. No extended spectrum β-lactamases were detected.

Scarce Evidence of Yogurt Lactic Acid Bacteria in Human Feces after Daily Yogurt Consumption by Healthy Volunteers

Science.gov (United States)

del Campo, Rosa; Bravo, Daniel; Cantón, Rafael; Ruiz-Garbajosa, Patricia; García-Albiach, Raimundo; Montesi-Libois, Alejandra; Yuste, Francisco-Javier; Abraira, Victor; Baquero, Fernando

2005-01-01

In a double-blind prospective study including 114 healthy young volunteers, the presence in human feces of the yogurt organisms Lactobacillus delbrueckii and Streptococcus thermophilus after repeated yogurt consumption (15 days) was analyzed by culture, specific PCR, and DNA hybridization of total fecal DNA. Detection of yogurt lactic acid bacteria in total fecal DNA by bacterial culture and PCR assay was consistently negative. DNA compatible with yogurt bacteria was found by hybridization experiments in only 10 (10.52%) of 96 individuals after consumption of fresh yogurt and in 2 (2.10%) of 96 individuals after consumption of pasteurized yogurt (P = 0.01). PMID:15640233

Investigation of Phenolic Compounds and Antioxidant Activity of Mentha spicata L. subsp. spicata and M. longifolia (L.) L. subsp. typhoides (Briq.) Harley Decoction and Infusion

OpenAIRE

ÖZER, Züleyha

2018-01-01

In present study, we report phenolic compounds and antioxidant activity of decoctionand infusion of Mentha spicata L. subsp. spicataand M. longifolia (L.) L. subsp. typhoides (Briq.) Harley. The quantitativeamounts of the phenolic contents were determined by LC-MS/MS.  The main compounds and amounts of M. spicata weredetermined as follow for decoction; caffeic acid, quercetagetin-3,6-dimethyletherand penduletin (4126.6; 2141.5; 1472.7 mg/kg dried herba, respectively), for infusion;fumaric aci...

Tomato fruit and seed colonization by Clavibacter michiganensis subsp. michiganensis through external and internal routes.

Science.gov (United States)

Tancos, Matthew A; Chalupowicz, Laura; Barash, Isaac; Manulis-Sasson, Shulamit; Smart, Christine D

2013-11-01

The Gram-positive bacterium Clavibacter michiganensis subsp. michiganensis, causal agent of bacterial wilt and canker of tomato, is an economically devastating pathogen that inflicts considerable damage throughout all major tomato-producing regions. Annual outbreaks continue to occur in New York, where C. michiganensis subsp. michiganensis spreads via infected transplants, trellising stakes, tools, and/or soil. Globally, new outbreaks can be accompanied by the introduction of contaminated seed stock; however, the route of seed infection, especially the role of fruit lesions, remains undefined. In order to investigate the modes of seed infection, New York C. michiganensis subsp. michiganensis field strains were stably transformed with a gene encoding enhanced green fluorescent protein (eGFP). A constitutively eGFP-expressing virulent C. michiganensis subsp. michiganensis isolate, GCMM-22, was used to demonstrate that C. michiganensis subsp. michiganensis could not only access seeds systemically through the xylem but also externally through tomato fruit lesions, which harbored high intra- and intercellular populations. Active movement and expansion of bacteria into the fruit mesocarp and nearby xylem vessels followed, once the fruits began to ripen. These results highlight the ability of C. michiganensis subsp. michiganensis to invade tomato fruits and seeds through multiple entry routes.

Mass transfer behavior in lactic acid fermentation using immobilized lactobacillus delbrueckii

Energy Technology Data Exchange (ETDEWEB)

Wang, H.; Seki, M.; Furusaki, S. [The University of Tokyo, Tokyo (Japan). Faculty of Engineering

1995-08-20

We performed simulation studies on mass transfer behavior for immobilized cells in lactic acid fermentation using the mathematical model developed previously. The simulations pointed to an unusual result; that lactate ion diffuses into the bead center from outside during the batch fermentation and the startup period of the continuous fermentation, whereas free lactic acid and protons diffuse in the opposite direction. This phenomenon is caused by the addition of base to keep pH constant in the broth. Also, using an appropriate buffer to control pH in the broth can reduce the inward diffusion of lactate ion and improve the productivity of lactic acid. A singular mass transfer phenomenon is expected to take place in other production processes using immobilized cells (or enzyme), where alkali solution is added to broth to keep pH constant. 9 refs., 6 figs.

Genetic variation in Mediterranean Helichrysum italicum (Asteraceae; Gnaphalieae): do disjunct populations of subsp. microphyllum have a common origin?

Science.gov (United States)

Galbany-Casals, M; Blanco-Moreno, J M; Garcia-Jacas, N; Breitwieser, I; Smissen, R D

2011-07-01

The yellow-flowered everlasting daisy Helichrysum italicum (Asteraceae, Gnaphalieae) is widely distributed in the Mediterranean basin, where it grows in continuous and widespread populations in diverse open habitats. Helichrysum italicum subsp. microphyllum has a disjunct distribution in the Balearic Islands (Majorca and Dragonera), Corsica, Sardinia, Crete and Cyprus. Numerous morphological intermediates between subsp. italicum and subsp. microphyllum are known from Corsica, where the two subspecies co-occur. The aims of the study were to investigate if subsp. microphyllum has a common origin, constituting an independent gene pool from subsp. italicum, or if the morphological differences between subsp. microphyllum and subsp. italicum have arisen independently in different locations from a common wider gene pool. Our analyses of AFLP, cpDNA sequences and morphological characters show that there is geographic structure to the genetic variation within H. italicum, with eastern and western Mediterranean groups, which do not correspond with the division into subsp. microphyllum and subsp. italicum as currently circumscribed. Local selection on quantitative trait loci provides sufficient explanation for the morphological divergence observed and is consistent with genetic data. Within the western Mediterranean group of the species we found considerable polymorphism in chloroplast DNA sequences among and within some populations. Comparison with chloroplast DNA sequences from other Helichrysum species showed that some chloroplast haplotypes are shared across species. © 2010 German Botanical Society and The Royal Botanical Society of the Netherlands.

Pork meat as a potential source of Salmonella enterica subsp. arizonae infection in humans.

Science.gov (United States)

Evangelopoulou, Grammato; Kritas, Spyridon; Govaris, Alexander; Burriel, Angeliki R

2014-03-01

Salmonella enterica subsp. arizonae was isolated from 13 of 123 slaughtered pigs in central Greece. The samples cultured were feces, ileum tissue, mesenteric lymph nodes, and gallbladder swabs. A total of 74 isolates from 492 samples were identified as Salmonella spp. by use of standard laboratory culture media and two commercial micromethods and by use of a polyvalent slide agglutination test for the detection of O and H antigens. Among them were 19 (25.68%) suspected to be S. enterica subsp. arizonae according to analysis with standard laboratory culture media. Of those, 14 were identified as S. enterica subsp. arizonae by the API 20E (bioMérieux, France) and the Microgen GnA+B-ID (Microgen Bioproducts, Ltd., United Kingdom) identification systems. All the isolates were tested for resistance to 23 antimicrobials. Strains identified as S. enterica subsp. arizonae were resistant to 17 (70.8%) antibiotics. The highest proportions of resistance were observed for sulfamethoxazole-trimethoprim (71.4%), tetracycline (71.4%), ampicillin (64.3%), and amoxicillin (57.1%). Two isolates were resistant to aztreonam (7.1%) and tigecycline (7.1%), used only for the treatment of humans. Thus, pork meat may play a role in the transmission of antibiotic-resistant S. enterica subsp. arizonae to human consumers. This is the first report of S. enterica subsp. arizonae isolation from pigs.

Improvement of DNA transfer frequency and transposon mutagenesis of Erwinia carotovora subsp. betavasculorum.

Science.gov (United States)

Rella, M; Axelrood, P E; Weinhold, A R; Schroth, M N

1989-01-01

The production of antibiotics and their role in microbial competition under natural conditions can be readily studied by the use of transposon mutants. Several antibiotic-producing strains of Erwinia carotovora subsp. betavasculorum were unable to accept foreign DNA. A plasmid delivery system was developed, using ethyl methanesulfonate mutagenesis, which entailed isolating E. carotovora subsp. betavasculorum mutants able to accept foreign DNA and transfer it to other strains. This enabled transposon mutagenesis of a wild-type antibiotic-producing strain of E. carotovora subsp. betavasculorum. Twelve antibiotic-negative mutants were isolated, and one of these showed a reduction in antibiotic production in vitro. Many of these mutants also showed a reduction in their ability to macerate potato tissue. The mutants were classified into four genetic groups on the basis of their genetic and phenotypic characteristics, indicating that several genes are involved in antibiotic biosynthesis by E. carotovora subsp. betavasculorum. PMID:2543291

Multilocus sequence typing reveals two evolutionary lineages of Acidovorax avenae subsp. citrulli.

Science.gov (United States)

Feng, Jianjun; Schuenzel, Erin L; Li, Jianqiang; Schaad, Norman W

2009-08-01

Acidovorax avenae subsp. citrulli, causal agent of bacterial fruit blotch, has caused considerable damage to the watermelon and melon industry in China and the United States. Understanding the emergence and spread of this pathogen is important for controlling the disease. To build a fingerprinting database for reliable identification and tracking of strains of A. avenae subsp. citrulli, a multilocus sequence typing (MLST) scheme was developed using seven conserved loci. The study included 8 original strains from the 1978 description of A. avenae subsp. citrulli, 51 from China, and 34 from worldwide collections. Two major clonal complexes (CCs), CC1 and CC2, were identified within A. avenae subsp. citrulli; 48 strains typed as CC1 and 45 as CC2. All eight original 1978 strains isolated from watermelon and melon grouped in CC1. CC2 strains were predominant in the worldwide collection and all but five were isolated from watermelon. In China, a major seed producer for melon and watermelon, the predominant strains were CC1 and were found nearly equally on melon and watermelon.

Streptococcus equi subsp zooepidemicus Invades and Survives in Epithelial Cells

DEFF Research Database (Denmark)

Skive, Bolette; Rohde, Manfred; Molinari, Gabriella

2017-01-01

Streptococcus equi subsp. zooepidemicus (S. zooepidemicus) is an opportunistic pathogen of several species including humans. S. zooepidemicus is found on mucus membranes of healthy horses, but can cause acute and chronic endometritis. Recently S. zooepidemicus was found able to reside in the endo......Streptococcus equi subsp. zooepidemicus (S. zooepidemicus) is an opportunistic pathogen of several species including humans. S. zooepidemicus is found on mucus membranes of healthy horses, but can cause acute and chronic endometritis. Recently S. zooepidemicus was found able to reside...

Quantitative assessment of Lactococcus lactis subsp. cremoris present in artisanal raw cow’s milk cheese

Directory of Open Access Journals (Sweden)

Milena Alicja Stachelska

2018-01-01

Full Text Available Lactococcus lactis subsp. cremoris belongs to lactic acid bacteria that play a crucial role in cheese production and it is known to be beneficial to human health. The aim of the study was to establish a rapid and accurate quantitative real-time polymerase chain reaction (qPCR method to detect and enumerate L. lactis subsp. cremoris in artisanal raw cow’s milk cheese. Artisanal raw cow’s milk cheese samples were used to check for presence and number of L. lactis subsp. cremoris strains. The method applies a set of target-specific PCR (polymerase chain reaction primers and a fluorogenic probe, and amplifies a part of the LACR_RS01280 gene that encodes the aminoacetone oxidase family flavin adenine dinucleotide (FAD binding enzyme. All 5 L. lactis subsp. cremoris strains examined were found to be qPCR positive. There was no signal recorded for 8 strains which belong to closely related species. The limit of detection amounted to ten copies per reaction and the assay indicated a linear dynamic range of seven logs. This method may be applied in detection and enumeration of L. lactis subsp. cremoris in cheese during its ripening. Moreover, it may be applied to examine the distribution of L. lactis subsp. cremoris during the cheese production and ripening.

Comparative Phenotypic and Molecular Genetic Profiling of Wild Lactococcus lactis subsp. lactis Strains of the L. lactis subsp. lactis and L. lactis subsp. cremoris Genotypes, Isolated from Starter-Free Cheeses Made of Raw Milk▿

Science.gov (United States)

Fernández, Elena; Alegría, Ángel; Delgado, Susana; Martín, M. Cruz; Mayo, Baltasar

2011-01-01

Twenty Lactococcus lactis strains with an L. lactis subsp. lactis phenotype isolated from five traditional cheeses made of raw milk with no added starters belonging to the L. lactis subsp. lactis and L. lactis subsp. cremoris genotypes (lactis and cremoris genotypes, respectively; 10 strains each) were subjected to a series of phenotypic and genetic typing methods, with the aims of determining their phylogenetic relationships and suitability as starters. Pulsed-field gel electrophoresis (PFGE) analysis of intact genomes digested with SalI and SmaI proved that all strains were different except for three isolates of the cremoris genotype, which showed identical PFGE profiles. Multilocus sequence typing (MLST) analysis using internal sequences of seven loci (namely, atpA, rpoA, pheS, pepN, bcaT, pepX, and 16S rRNA gene) revealed considerable intergenotype nucleotide polymorphism, although deduced amino acid changes were scarce. Analysis of the MLST data for the present strains and others from other dairy and nondairy sources showed that all of them clustered into the cremoris or lactis genotype group, by using both independent and combined gene sequences. These two groups of strains also showed distinctive carbohydrate fermentation and enzyme activity profiles, with the strains in the cremoris group showing broader profiles. However, the profiles of resistance/susceptibility to 16 antibiotics were very similar, showing no atypical resistance, except for tetracycline resistance in three identical cremoris genotype isolates. The numbers and concentrations of volatile compounds produced in milk by the strains belonging to these two groups were clearly different, with the cremoris genotype strains producing higher concentrations of more branched-chain, derived compounds. Together, the present results support the idea that the lactis and cremoris genotypes of phenotypic Lactococcus lactis subsp. lactis actually represent true subspecies. Some strains of the two subspecies

Protein Profile and Plasmid Content of Lactococcus lactis subsp. lactis LL52 and Lactococcus lactis subsp. cremoris LC79 Strains under Several Stress Conditions

OpenAIRE

LALE, Rahmi; TÜKEL, Çağla; AKÇELİK, Mustafa

2014-01-01

Differences in the protein and plasmid content of 2 Lactococcus lactis strains, L. lactis subsp. lactis LL52 and L. lactis subsp. cremoris LC79, under the stresses of high and low temperature, osmotic shock, and low pH were determined. We identified 3 new proteins with molecular masses of 16.0, 29.4, and 45.0 kDa as high temperature stress response specific in strain LL52. High temperature stress did not cause any changes in the protein content of strain LC79. Proteins that were specific for ...

Bioaccessible Antioxidants in Milk Fermented by Bifidobacterium longum subsp. longum Strains

Science.gov (United States)

Gagnon, Mérilie; Savard, Patricia; Rivière, Audrey; LaPointe, Gisèle

2015-01-01

Bifidobacterium longum subsp. longum is among the dominant species of the human gastrointestinal microbiota and could thus have potential as probiotics. New targets such as antioxidant properties have interest for beneficial effects on health. The objective of this study was to evaluate the bioaccessibility of antioxidants in milk fermented by selected B. longum subsp. longum strains during in vitro dynamic digestion. The antioxidant capacity of cell extracts from 38 strains, of which 32 belong to B. longum subsp. longum, was evaluated with the ORAC (oxygen radical absorbance capacity) method. On the basis of screening and gene sequence typing by multilocus locus sequence analysis (MLSA), five strains were chosen for fermenting reconstituted skim milk. Antioxidant capacity varied among the strains tested (P = 0.0009). Two strains of B. longum subsp. longum (CUETM 172 and 171) showed significantly higher ORAC values than the other bifidobacteria strains. However, there does not appear to be a relationship between gene sequence types and antioxidant capacity. The milk fermented by each of the five strains selected (CUETM 268, 172, 245, 247, or PRO 16-10) did not have higher initial ORAC values compared to the nonfermented milk samples. However, higher bioaccessibility of antioxidants in fermented milk (175–358%) was observed during digestion. PMID:25802836

MAO-A inhibition profiles of some benzophenone glucosides from Gentiana verna subsp. pontica

DEFF Research Database (Denmark)

Kaya, Duygu; Jäger, Anna; Yalçin, Funda N

2014-01-01

Gentiana verna L. subsp. pontica (Soltok.) Hayek, G. pyrenaica L., and G. verna L. subsp. balcanica Pritchard from Turkey were tested for their MAO-A inhibitory effects. A photometric peroxidase linked MAO-A bioassay performed on the H20 extracts prepared from the methanolic extracts of the title...

A single or multistage mycobacterium avium subsp. paratuberculosis subunit vaccine

DEFF Research Database (Denmark)

2014-01-01

The present invention provides one or more immunogenic polypeptides for use in a preventive or therapeutic vaccine against latent or active infection in a human or animal caused by a Mycobacterium species, e.g. Mycobacterium avium subsp. paratuberculosis. Furthermore a single or multi-phase vaccine...... comprising the one or more immunogenic polypeptides is provided for administration for the prevention or treatment of infection with a Mycobacterium species, e.g. Mycobacterium avium subsp. paratuberculosis. Additionally, nucleic acid vaccines, capable of in vivo expression of the multi-phase vaccine...

Bacterial Canker (Clavibacter michiganensis subsp. michiganensis) of tomato in commercial seed produced in Indonesia

NARCIS (Netherlands)

Anwar, A.; Zouwen, van der P.S.; Ilyas, S.; Wolf, van der J.M.

2004-01-01

In 2002, Clavibacter michiganensis subsp. michiganensis (Smith) Davis, the causal organism of bacterial canker of tomato (Lycopersicon esculentum), was isolated from two of six commercial asymptomatic tomato seed lots produced on Java in Indonesia. C. michiganensis subsp. michiganensis has not been

Immunomodulation in gut-associated lymphoid tissue of neonatal chicks by immunobiotic diets.

Science.gov (United States)

Sato, K; Takahashi, K; Tohno, M; Miura, Y; Kamada, T; Ikegami, S; Kitazawa, H

2009-12-01

Developmental changes in immunocompetent cells of the gut during the first week posthatch were determined in broiler chicks fed immunobiotic lactic acid bacteria in the form of Lactobacillus jensenii TL2937-, Lactobacillus gasseri JCM1131(T)-, Lactobacillus delbrueckii ssp. bulgaricus NIAIB6-, or L. gasseri TL2919-supplemented diets. The relative weights of spleen and bursa of Fabricius in chicks fed the immunobiotic diets were slightly higher than the control valued at 1 and 3 d of age, with the exception of spleen weight in the L. gasseri JCM1131(T) at 3 d of age, the bursa of Fabricius weight in the L. gasseri JCM1131(T) at 1 and 3 d of age, and bursa of Fabricius weight in the L. gasseri TL2919 group at 1 d of age. There were no significant differences in body and liver weights among the treatments. When chicks were fed the L. jensenii TL2937- or L. gasseri TL2919-supplemented diets, expression of T cell-related mRNA [cluster of differentiation 3 (CD3), interleukin-2 (IL-2), and interferon-gamma (IFN-gamma)] in the foregut was significantly higher than that of control chicks at 3 or 7 d of age. Expression levels of toll-like receptor (TLR) mRNA tended to increase in the foregut of chicks fed the immunobiotic diets, except for the L. delbrueckii ssp. bulgaricus NIAIB6, compared with expression levels in control chicks. The Bu-1 mRNA expression levels in the bursa of Fabricius were not affected by the supplementations with immunobiotic lactic acid bacteria. These results show that immunobiotics, particularly L. gasseri TL2919, might be useful as immunomodulators to stimulate the gut-associated immune system in neonatal chicks, and thereby protect them from disease without decreasing growth performance as a possible substitution of antibiotics.

Laminaria japonica Extract, an Inhibitor of Clavibater michiganense Subsp. Sepedonicum.

Directory of Open Access Journals (Sweden)

Jin Cai

Full Text Available Bacterial ring rot of potato is one of the most serious potato plant and tuber diseases. Laminaria japonica extract was investigated for its antimicrobial activity against Clavibater michiganense subsp. sepedonicum (Spieckermann & Kotthoff Davis et al., the causative agent of bacterial ring rot of potato. The results showed that the optimum extraction conditions of antimicrobial substances from L. japonica were an extraction temperature of 80°C, an extraction time of 12 h, and a solid to liquid ratio of 1∶25. Active compounds of L. japonica were isolated by solvent partition, thin layer chromatography (TLC and column chromatography. All nineteen fractionations had antimicrobial activities against C. michiganense subsp. sepedonicum, while Fractionation three (Fr.3 had the highest (P<0.05 antimicrobial activity. Chemical composition analysis identified a total of 26 components in Fr.3. The main constituents of Fr.3 were alkanes (80.97%, esters (5.24%, acids (4.87% and alcohols (2.21%. Antimicrobial activity of Fr.3 against C. michiganense subsp. sepedonicum could be attributed to its ability to damage the cell wall and cell membrane, induce the production of reactive oxygen species (ROS, increase cytosolic Ca2+ concentration, inhibit the glycolytic pathway (EMP and tricarboxylic acid (TCA cycle, inhibit protein and nucleic acid synthesis, and disrupt the normal cycle of DNA replication. These findings indicate that L. japonica extracts have potential for inhibiting C. michiganense subsp. sepedonicum.

Reproductive biology of Corymbia citriodora subsp. variegata and ...

African Journals Online (AJOL)

Reproductive biology of Corymbia citriodora subsp. variegata and effective pollination across its native range in Queensland, Australia. CFE Bacles, J Brooks, DJ Lee, PM Schenk, AJ Lowe, A Kremer ...

Cloning, Sequencing, and Expression of the Pyruvate Carboxylase Gene in Lactococcus lactis subsp. lactis C2†

OpenAIRE

Wang, H.; O'Sullivan, D. J.; Baldwin, K. A.; McKay, L. L.

2000-01-01

A functional pyc gene was isolated from Lactococcus lactis subsp. lactis C2 and was found to complement a Pyc defect in L. lactis KB4. The deduced lactococcal Pyc protein was highly homologous to Pyc sequences of other bacteria. The pyc gene was also detected in Lactococcus lactis subsp. cremoris and L. lactis subsp. lactis bv. diacetylactis strains.

Rapid and sensitive method to identify Mycobacterium avium subsp. paratuberculosis in cow's milk by DNA methylase genotyping.

Science.gov (United States)

Mundo, Silvia Leonor; Gilardoni, Liliana Rosa; Hoffman, Federico José; Lopez, Osvaldo Jorge

2013-03-01

Paratuberculosis is an infectious, chronic, and incurable disease that affects ruminants, caused by Mycobacterium avium subsp. paratuberculosis. This bacterium is shed primarily through feces of infected cows but can be also excreted in colostrum and milk and might survive pasteurization. Since an association of genomic sequences of M. avium subsp. paratuberculosis in patients with Crohn's disease has been described; it is of interest to rapidly detect M. avium subsp. paratuberculosis in milk for human consumption. IS900 insertion is used as a target for PCR amplification to identify the presence of M. avium subsp. paratuberculosis in biological samples. Two target sequences were selected: IS1 (155 bp) and IS2 (94 bp). These fragments have a 100% identity among all M. avium subsp. paratuberculosis strains sequenced. M. avium subsp. paratuberculosis was specifically concentrated from milk samples by immunomagnetic separation prior to performing PCR. The amplicons were characterized using DNA methylase Genotyping, i.e., the amplicons were methylated with 6-methyl-adenine and digested with restriction enzymes to confirm their identity. The methylated amplicons from 100 CFU of M. avium subsp. paratuberculosis can be visualized in a Western blot format using an anti-6-methyl-adenine monoclonal antibody. The use of DNA methyltransferase genotyping coupled to a scintillation proximity assay allows for the detection of up to 10 CFU of M. avium subsp. paratuberculosis per ml of milk. This test is rapid and sensitive and allows for automation and thus multiple samples can be tested at the same time.

Influence of galactooligosaccharides and modified waxy maize starch on some attributes of yogurt.

Science.gov (United States)

Prasad, Laxmi N; Sherkat, Frank; Shah, Nagendra P

2013-01-01

This study examined the influence of galactooligosaccharides (GOS) and modified waxy maize starch (MWMS) addition on the growth of starter cultures, and syneresis and firmness of low-fat yogurt during storage for 28 d at 4 °C. The control yogurt (CY) was prepared without any prebiotics. Incorporation of 2.0% (w/v) GOS improved the growth of L. delbrueckii ssp. bulgaricus ATCC 11842 resulting in a shorter fermentation time. There was a significant (P yogurt made with GOS (GOSY) as measured by absorbance value (0.728). Addition of GOS resulted in higher (P 0.05) difference in the firmness among the 3 types of yogurt. © 2012 Institute of Food Technologists®

Functional Starters for Functional Yogurt

Directory of Open Access Journals (Sweden)

Mattia P. Arena

2015-02-01

Full Text Available In this study, we investigated the multifunctionality (microbial starters and probiotics of Lactobacillus plantarum WCFS1 and Lactobacillus plantarum CECT 8328 strains used as microbial starters for the production of yogurt in combination with Lactobacillus delbrueckii ssp. bulgaricus and Streptococcus thermophilus. The ability of the probiotic strains to survive oro-gastrointestinal stresses was monitored by an in vitro assay simulating the human digestive tract. The transcriptional level of several genes involved in the immune response suggested that the probiotic strains may have a favorable influence on immunomodulation. Overall, this study revealed that the tested Lactobacilli exhibited suitable technological features for yogurt production and might be used to formulate novel food with immunomodulating effects.

Influence of nitrogen sources on growth and fermentation performance of different wine yeast species during alcoholic fermentation

DEFF Research Database (Denmark)

Kemsawasd, Varongsiri; Monteiro Lomba Viana, Tiago; Ardö, Ylva

2015-01-01

-Saccharomyces yeast species (Lachancea thermotolerans, Metschnikowia pulcherrima, Hanseniaspora uvarum and Torulaspora delbrueckii) was investigated during alcoholic fermentation. Briefly, the N-sources with beneficial effects on all performance parameters (or for the majority of them) for each yeast species were...... for L. thermotolerans, H. uvarum and M. pulcherrima, single amino acids affected growth and fermentation performance to the same extent as the mixtures. Moreover, we found groups of N-sources with similar effects on the growth and/or fermentation performance of two or more yeast species. Finally...... species under oxygen-limited conditions, which, in turn, may be used to, e.g. optimize growth and fermentation performance of the given yeast upon N-source supplementation during wine fermentations....

Isolation of Salmonella enterica subsp. enterica (O:4,5:i and Salmonella enterica subsp. Typhimurium from free-living domestic pigeons (Columba livia

Directory of Open Access Journals (Sweden)

R.C. Rocha-e-Silva

2014-10-01

Full Text Available The present study reports the isolation of Salmonella enterica in organs of free-living domestic pigeons. In the clinic examination, the presence of feces in the peri-cloacal and abdominal regions were observed, as well as symptoms such as cachexy, incoordination and opisthotonos. Before any therapeutic protocol was applied the bird died and a necropsy was then performed for the removal of spleen, liver, kidney and intestine for bacteriological examination and antibiotic sensitivity test. Salmonella enterica subsp.enterica (O:4,5:i- and Salmonella enterica subsp. enterica serovar Typhimurium were isolated from the liver and intestine and the sensitivity test demonstrated that these strains are sensitive to several antibiotics.

Application of Impedance Microbiology for Evaluating Potential Acidifying Performances of Starter Lactic Acid Bacteria to Employ in Milk Transformation.

Science.gov (United States)

Bancalari, Elena; Bernini, Valentina; Bottari, Benedetta; Neviani, Erasmo; Gatti, Monica

2016-01-01

Impedance microbiology is a method that enables tracing microbial growth by measuring the change in the electrical conductivity. Different systems, able to perform this measurement, are available in commerce and are commonly used for food control analysis by mean of measuring a point of the impedance curve, defined "time of detection." With this work we wanted to find an objective way to interpret the metabolic significance of impedance curves and propose it as a valid approach to evaluate the potential acidifying performances of starter lactic acid bacteria to be employed in milk transformation. To do this it was firstly investigated the possibility to use the Gompertz equation to describe the data coming from the impedance curve obtained by mean of BacTrac 4300®. Lag time (λ), maximum specific M% rate (μmax), and maximum value of M% (Yend) have been calculated and, given the similarity of the impedance fitted curve to the bacterial growth curve, their meaning has been interpreted. Potential acidifying performances of eighty strains belonging to Lactobacillus helveticus, Lactobacillus delbrueckii subsp. bulgaricus, Lactococcus lactis , and Streptococcus thermophilus species have been evaluated by using the kinetics parameters, obtained from Excel add-in DMFit version 2.1. The novelty and importance of our findings, obtained by means of BacTrac 4300®, is that they can also be applied to data obtained from other devices. Moreover, the meaning of λ, μmax, and Yend that we have extrapolated from Modified Gompertz equation and discussed for lactic acid bacteria in milk, can be exploited also to other food environment or other bacteria, assuming that they can give a curve and that curve is properly fitted with Gompertz equation.

Effects of probiotics and antibiotics on the intestinal homeostasis in a computer controlled model of the large intestine

Directory of Open Access Journals (Sweden)

Rehman Ateequr

2012-03-01

Full Text Available Abstract Background Antibiotic associated diarrhea and Clostridium difficile infection are frequent complications of broad spectrum antibiotic therapy. Probiotic bacteria are used as therapeutic and preventive agents in these disorders, but the exact functional mechanisms and the mode of action are poorly understood. The effects of clindamycin and the probiotic mixture VSL#3 (containing the 8 bacterial strains Streptococcus thermophilus, Bifidobacterium breve, Bifidobacterium longum, Bifidobacterium infantis, Lactobacillus acidophilus, Lactobacillus plantarum, Lactobacillus paracasei and Lactobacillus delbrueckii subsp. Bulgaricus consecutively or in combination were investigated and compared to controls without therapy using a standardized human fecal microbiota in a computer-controlled in vitro model of large intestine. Microbial metabolites (short chain fatty acids, lactate, branched chain fatty acids, and ammonia and the intestinal microbiota were analyzed. Results Compared to controls and combination therapy, short chain fatty acids and lactate, but also ammonia and branched chain fatty acids, were increased under probiotic therapy. The metabolic pattern under combined therapy with antibiotics and probiotics had the most beneficial and consistent effect on intestinal metabolic profiles. The intestinal microbiota showed a decrease in several indigenous bacterial groups under antibiotic therapy, there was no significant recovery of these groups when the antibiotic therapy was followed by administration of probiotics. Simultaneous application of anti- and probiotics had a stabilizing effect on the intestinal microbiota with increased bifidobacteria and lactobacilli. Conclusions Administration of VSL#3 parallel with the clindamycin therapy had a beneficial and stabilizing effect on the intestinal metabolic homeostasis by decreasing toxic metabolites and protecting the endogenic microbiota from destruction. Probiotics could be a reasonable

The Karyotype of Alstroemeria diluta Ehr. Bayer subsp. chrysantha (Alstroemeriaceae Karyotype of Alstroemeria diluta Ehr. Bayer subsp. chrysantha (Alstroemeriaceae

Directory of Open Access Journals (Sweden)

Carlos M Baeza

2010-12-01

Full Text Available The karyotype of Alstroemeria diluta subsp. chrysantha Ehr. Bayer from Chile was examined. The species has 2n = 2x = 16 chromosomes, with 4m + 4sm + 2st-sat + 4t + 2t-sat. The reported karyotype is very asymmetrical (AsK % = 71.4 and Syi = 40.0%. This karyotype is similar to that published previously for Alstroemeria graminea Phil.Alstroemeria diluta subsp. chrysantha Ehr. Bayer (Alstroemeriaceae fue examinada citológicamente. Esta especie presenta un número cromosómico somático de 2n = 2x = 16 cromosomas, con una fórmula haploide constituida por 4m + 4sm + 2st-sat + 4t + 2t-sat cromosomas. El cariotipo es muy asimétrico, con valores de AsK % = 71,4 y Syi = 40,0%. Estos resultados se compararon con los de Alstroemeria graminea Phil., especie que presenta un cariotipo muy similar.

Bioprocessing of some agro-industrial residues for endoglucanase production by the new subsp.; Streptomyces albogriseolus subsp. cellulolyticus strain NEAE-J

Directory of Open Access Journals (Sweden)

Noura El-Ahmady El-Naggar

2014-06-01

Full Text Available The use of low cost agro-industrial residues for the production of industrial enzymes is one of the ways to reduce significantly production costs. Cellulase producing actinomycetes were isolated from soil and decayed agricultural wastes. Among them, a potential culture, strain NEAE-J, was selected and identified on the basis of morphological, cultural, physiological and chemotaxonomic properties, together with 16S rDNA sequence. It is proposed that strain NEAE-J should be included in the species Streptomyces albogriseolus as a representative of a novel sub-species, Streptomyces albogriseolus subsp. cellulolyticus strain NEAE-J and sequencing product was deposited in the GenBank database under accession number JN229412. This organism was tested for its ability to produce endoglucanase and release reducing sugars from agro-industrial residues as substrates. Sugarcane bagasse was the most suitable substrate for endoglucanase production. Effects of process variables, namely incubation time, temperature, initial pH and nitrogen source on production of endoglucanase by submerged fermentation using Streptomyces albogriseolus subsp. cellulolyticus have been studied. Accordingly optimum conditions have been determined. Incubation temperature of 30 ºC after 6 days, pH of 6.5, 1% sugarcane bagasse as carbon source and peptone as nitrogen source were found to be the optimum for endoglucanase production. Optimization of the process parameters resulted in about 2.6 fold increase in the endoglucanase activity. Therefore, Streptomyces albogriseolus subsp. cellulolyticus coud be potential microorganism for the intended application.

Bioprocessing of some agro-industrial residues for endoglucanase production by the new subsp.; Streptomyces albogriseolus subsp. cellulolyticus strain NEAE-J

Science.gov (United States)

El-Naggar, Noura El-Ahmady; Abdelwahed, Nayera A.M.; Saber, Wesam I.A.; Mohamed, Asem A.

2014-01-01

The use of low cost agro-industrial residues for the production of industrial enzymes is one of the ways to reduce significantly production costs. Cellulase producing actinomycetes were isolated from soil and decayed agricultural wastes. Among them, a potential culture, strain NEAE-J, was selected and identified on the basis of morphological, cultural, physiological and chemotaxonomic properties, together with 16S rDNA sequence. It is proposed that strain NEAE-J should be included in the species Streptomyces albogriseolus as a representative of a novel sub-species, Streptomyces albogriseolus subsp. cellulolyticus strain NEAE-J and sequencing product was deposited in the GenBank database under accession number JN229412. This organism was tested for its ability to produce endoglucanase and release reducing sugars from agro-industrial residues as substrates. Sugarcane bagasse was the most suitable substrate for endoglucanase production. Effects of process variables, namely incubation time, temperature, initial pH and nitrogen source on production of endoglucanase by submerged fermentation using Streptomyces albogriseolus subsp. cellulolyticus have been studied. Accordingly optimum conditions have been determined. Incubation temperature of 30 °C after 6 days, pH of 6.5, 1% sugarcane bagasse as carbon source and peptone as nitrogen source were found to be the optimum for endoglucanase production. Optimization of the process parameters resulted in about 2.6 fold increase in the endoglucanase activity. Therefore, Streptomyces albogriseolus subsp. cellulolyticus coud be potential microorganism for the intended application. PMID:25242966

Anoxybacillus kamchatkensis subsp. asaccharedens subsp. nov., a thermophilic bacterium isolated from a hot spring in Batman.

Science.gov (United States)

Gul-Guven, Reyhan; Guven, Kemal; Poli, Annarita; Nicolaus, Barbara

2008-12-01

A new thermophilic spore-forming strain KG8(T) was isolated from the mud of Taslidere hot spring in Batman. Strain KG8(T) was aerobe, Gram-positive, rod-shaped, motile, occurring in pairs or filamentous. Growth was observed from 35-65 degrees C (optimum 55 degrees C) and at pH 5.5-9.5 (optimum pH 7.5). It was capable of utilizing starch, growth was observed until 3% NaCl (w/v) and it was positive for nitrate reduction. On the basis of 16S rRNA gene sequence similarity, strain KG8(T) was shown to be related most closely to Anoxybacillus species. Chemotaxonomic data (major isoprenoid quinone-menaquinone-7; major fatty acid-iso-C15:0 and iso-C17:0) supported the affiliation of strain KG8(T) to the genus Anoxybacillus. The results of DNA-DNA hybridization, physiological and biochemical tests allowed genotypic and phenotypic differentiation of strain KG8(T). Based on these results we propose assigning a novel subspecies of Anoxybacillus kamchatkensis, to be named Anoxybacillus kamchatkensis subsp. asaccharedens subsp. nov. with the type strain KG8(T) (DSM 18475(T)=CIP 109280(T)).

Chemical composition of essential oil of mentha longifolia l. subsp. longifolia growing wild

International Nuclear Information System (INIS)

Okut, N.; Yagmur, M.; Yildirim, B.

2017-01-01

The essential oil of Mentha longifolia L., is very important to some culinary usage and antimicrobial activity. The essential oil of Mentha longifolia subsp. longifolia growing in the Bahcesaray area (Van Province, Turkey) was studied. This study designed for determine of essential oil constituent Mentha longifolia subsp. longifolia that collected from wild area. Mint leaves sample essential oils obtained by hydro distillation and essential oil components were determined using GC-MS. The main component of wild grown Mentha longifolia subsp. longifolia was Menthone (19.31%). Second one and others were Pulegone (12.42%), Piperitone (11.05%), Dihydrocarvon (8.32%), Limonene (6.1%), 3-Terpinolenone (5.66%), 1,8-Cineole (4.37%), Germacrene D (3.38%) and Caryopyllene (3.19%), respectively. (author)

Stable transformation of the gram-positive phytopathogenic bacterium Clavibacter michiganensis subsp. sepedonicus with several cloning vectors.

Science.gov (United States)

Laine, M J; Nakhei, H; Dreier, J; Lehtilä, K; Meletzus, D; Eichenlaub, R; Metzler, M C

1996-05-01

In this paper we describe transformation of Clavibacter michiganensis subsp. sepedonicus, the potato ring rot bacterium, with plasmid vectors. Three of the plasmids used, pDM100, pDM302, and pDM306, contain the origin of replication from pCM1, a native plasmid of C. michiganensis subsp. michiganensis. We constructed two new cloning vectors, pHN205 and pHN216, by using the origin of replication of pCM2, another native plasmid of C. michiganensis subsp. michiganensis. Plasmids pDM302, pHN205, and pHN216 were stably maintained without antibiotic selection in various strains of C. michiganensis subsp. sepedonicus. We observed that for a single plasmid, different strains of C. michiganensis subsp. sepedonicus showed significantly different transformation efficiencies. We also found unexplained strain-to-strain differences in stability with various plasmid constructions containing different arrangements of antibiotic resistance genes and origins of replication. We examined the effect of a number of factors on transformation efficiency. The best transformation efficiencies were obtained when C. michiganensis subsp. sepedonicus cells were grown on DM agar plates, harvested during the early exponential growth phase, and used fresh (without freezing) for electroporation. The maximal transformation efficiency obtained was 4.6 x 10(4) CFU/microgram of pHN216 plasmid DNA. To demonstrate the utility of this transformation system, we cloned a beta-1,4-endoglucanase-encoding gene from C. michiganensis subsp. sepedonicus into pHN216. When this construction, pHN216:C8, was electroporated into competent cells of a cellulase-deficient mutant, it restored cellulase production to almost wild-type levels.

Rapid detection of Mycobacterium avium subsp. paratuberculosis ...

African Journals Online (AJOL)

Therefore, alternative diagnostic tests such as PCR, are needed for quick detection of infected animals. In this study, the conventional enrichment and isolation procedure and two IS900-based PCR methods for detection of Mycobactrium avium subsp. paratuberculosis in clinical samples from zoo animals and cattle were ...

Mean effective sensitivity for Mycobacterium avium subsp paratuberculosis infection in cattle herds

DEFF Research Database (Denmark)

Kirkeby, Carsten; Græsbøll, Kaare; Hisham Beshara Halasa, Tariq

2015-01-01

Background: Mycobacterium avium subsp. paratuberculosis (MAP) infections in cattle are generally challenging to detect and cost-effective test strategies are consequently difficult to identify. MAP-specific antibody ELISAs for milk and serum are relatively inexpensive, but their utility is influe......Background: Mycobacterium avium subsp. paratuberculosis (MAP) infections in cattle are generally challenging to detect and cost-effective test strategies are consequently difficult to identify. MAP-specific antibody ELISAs for milk and serum are relatively inexpensive, but their utility...

Xylella fastidiosa Isolates from Both subsp. multiplex and fastidiosa Cause Disease on Southern Highbush Blueberry (Vaccinium sp.) Under Greenhouse Conditions.

Science.gov (United States)

Oliver, J E; Cobine, P A; De La Fuente, L

2015-07-01

Xylella fastidiosa is a xylem-limited gram-negative plant pathogen that affects numerous crop species, including grape, citrus, peach, pecan, and almond. Recently, X. fastidiosa has also been found to be the cause of bacterial leaf scorch on blueberry in the southeastern United States. Thus far, all X. fastidiosa isolates obtained from infected blueberry have been classified as X. fastidiosa subsp. multiplex; however, X. fastidiosa subsp. fastidiosa isolates are also present in the southeastern United States and commonly cause Pierce's disease of grapevines. In this study, seven southeastern U.S. isolates of X. fastidiosa, including three X. fastidiosa subsp. fastidiosa isolates from grape, one X. fastidiosa subsp. fastidiosa isolate from elderberry, and three X. fastidiosa subsp. multiplex isolates from blueberry, were used to infect the southern highbush blueberry 'Rebel'. Following inoculation, all isolates colonized blueberry, and isolates from both X. fastidiosa subsp. multiplex and X. fastidiosa subsp. fastidiosa caused symptoms, including characteristic stem yellowing and leaf scorch symptoms as well as dieback of the stem tips. Two X. fastidiosa subsp. multiplex isolates from blueberry caused more severe symptoms than the other isolates examined, and infection with these two isolates also had a significant impact on host mineral nutrient content in sap and leaves. These findings have potential implications for understanding X. fastidiosa host adaptation and expansion and the development of emerging diseases caused by this bacterium.

Intoxicação espontânea por Ipomoea carnea subsp. fistulosa (Convolvulaceae em bovinos no Pantanal Matogrossense Spontaneous Ipomoea carnea subsp. fistulosa (Convolvulaceae poisoning of cattle in the Brazilian Pantanal

Directory of Open Access Journals (Sweden)

Nadia A.B. Antoniassi

2007-10-01

Full Text Available Relata-se a intoxicação espontânea por Ipomoea carnea subsp. fistulosa (canudo, algodoeiro em bovinos no Pantanal Matogrossense. As investigações iniciaram após a morte de 12 bovinos, de um rebanho de 500 animais, criados em uma extensa área intensamente infestada por I. carnea subsp. fistulosa com escassa disponibilidade de outra forragem. As mortes ocorreram entres os meses de junho e setembro de 2006. O quadro clínico foi caracterizado por emagrecimento e sinais neurológicos com dificuldade locomotora. Um bovino foi necropsiado sem que se observassem alterações macroscópicas significativas. Histologicamente havia tumefação e vacuolização celular, em neurônios, células acinares pancreáticas, tubulares renais e foliculares da tireóide. Bovinos com quadro clínico similar foram retirados da área invadida por I. carnea subsp. fistulosa e colocadas em áreas com pastagem nativa e de Brachiaria sp. e apresentaram melhora clínica após período de 15 dias.A spontaneous Ipomoea carnea subsp. fistulosa (canudo, algodoeiro poisoning of cattle in the county of Poconé, Brazilian Pantanal, is reported. The investigation began after 12 cattle had died from a flock of 500 animals maintained in an extensive area intensely infested by I. carnea subsp. fistulosa with scarce availability of other fodder plants. The deaths occurred from June to September of 2006. Clinical signs were loss of weight and neurological deficits with hypermetry and incoordination. No significant gross lesions were observed at postmortem examination of one bovine. Histological changes comprised widespread cytoplasmic vacuolation of neurons, cells of the thyroid, kidney and pancreas. Cattle with similar clinical picture, that had been removed from the area invaded by I. carnea subsp. fistulosa and placed into areas with native and Brachiaria sp. pasture, recovered clinically within 15 days.

Isolation of Bartonella henselae and Two New Bartonella Subspecies, Bartonella koehlerae Subspecies boulouisii subsp. nov. and Bartonella koehlerae Subspecies bothieri subsp. nov. from Free-Ranging Californian Mountain Lions and Bobcats

Science.gov (United States)

Chomel, Bruno B.; Molia, Sophie; Kasten, Rickie W.; Borgo, Gina M.; Stuckey, Matthew J.; Maruyama, Soichi; Chang, Chao-chin; Haddad, Nadia; Koehler, Jane E.

2016-01-01

Domestic cats are the natural reservoir of Bartonella henselae, B. clarridgeiae and B. koehlerae. To determine the role of wild felids in the epidemiology of Bartonella infections, blood was collected from 14 free-ranging California mountain lions (Puma concolor) and 19 bobcats (Lynx rufus). Bartonella spp. were isolated from four (29%) mountain lions and seven (37%) bobcats. These isolates were characterized using growth characteristics, biochemical reactions, molecular techniques, including PCR-RFLP of selected genes or interspacer region, pulsed-field gel electrophoresis (PFGE), partial sequencing of several genes, and DNA-DNA hybridization. Two isolates were identical to B. henselae genotype II. All other isolates were distinguished from B. henselae and B. koehlerae by PCR-RFLP of the gltA gene using endonucleases HhaI, TaqI and AciI, with the latter two discriminating between the mountain lion and the bobcat isolates. These two novel isolates displayed specific PFGE profiles distinct from B. henselae, B. koehlerae and B. clarridgeiae. Sequences of amplified gene fragments from the three mountain lion and six bobcat isolates were closely related to, but distinct from, B. henselae and B. koehlerae. Finally, DNA-DNA hybridization studies demonstrated that the mountain lion and bobcat strains are most closely related to B. koehlerae. We propose naming the mountain lion isolates B. koehlerae subsp. boulouisii subsp. nov. (type strain: L-42-94), and the bobcat isolates B. koehlerae subsp. bothieri subsp. nov. (type strain: L-17-96), and to emend B. koehlerae as B. koehlerae subsp. koehlerae. The mode of transmission and the zoonotic potential of these new Bartonella subspecies remain to be determined. PMID:26981874

A Rapid Method for Quantifying Viable Mycobacterium avium subsp. paratuberculosis in Cellular Infection Assays

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Pooley, Hannah B.; de Silva, Kumudika; Purdie, Auriol C.; Begg, Douglas J.; Whittington, Richard J.

2016-01-01

ABSTRACT Determining the viability of bacteria is a key outcome of in vitro cellular infection assays. Currently, this is done by culture, which is problematic for fastidious slow-growing bacteria such as Mycobacterium avium subsp. paratuberculosis, where it can take up to 4 months to confirm growth. This study aimed to identify an assay that can rapidly quantify the number of viable M. avium subsp. paratuberculosis cells in a cellular sample. Three commercially available bacterial viability assays along with a modified liquid culture method coupled with high-throughput quantitative PCR growth detection were assessed. Criteria for assessment included the ability of each assay to differentiate live and dead M. avium subsp. paratuberculosis organisms and their accuracy at low bacterial concentrations. Using the culture-based method, M. avium subsp. paratuberculosis growth was reliably detected and quantified within 2 weeks. There was a strong linear association between the 2-week growth rate and the initial inoculum concentration. The number of viable M. avium subsp. paratuberculosis cells in an unknown sample was quantified based on the growth rate, by using growth standards. In contrast, none of the commercially available viability assays were suitable for use with samples from in vitro cellular infection assays. IMPORTANCE Rapid quantification of the viability of Mycobacterium avium subsp. paratuberculosis in samples from in vitro cellular infection assays is important, as it allows these assays to be carried out on a large scale. In vitro cellular infection assays can function as a preliminary screening tool, for vaccine development or antimicrobial screening, and also to extend findings derived from experimental animal trials. Currently, by using culture, it takes up to 4 months to obtain quantifiable results regarding M. avium subsp. paratuberculosis viability after an in vitro infection assay; however, with the quantitative PCR and liquid culture method

Arabis soyeri Reuter ex Huet subsp. soyeri (Brassicaceae en el Pirineo aragonés [Arabis soyeri Reuter & Huet subsp. soyeri (Brassicaceae, in the Aragonese Pyrenees

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José Vicente FERRÁNDEZ PALACIO

2012-12-01

Full Text Available RESUMEN: En esta nota confirmamos la presencia de Arabis soyeri subsp. soyeri en el Pirineo aragonés (provincia de Huesca. Esta cita oscense se sitúa en el límite SW de su área de distribución endémica. Además, comentamos algunos aspectos sobre su autoecología y conservación.SUMMARY: Arabis soyeri Reuter & Huet subsp. soyeri is confirmed for the flora of the Aragonese Pyrenees (Huesca province, Spain. Moreower, this new station is located on the south-western border of its endemic range. Some aspects on its autecology and conservation are discussed as well.

Stable transformation of the gram-positive phytopathogenic bacterium Clavibacter michiganensis subsp. sepedonicus with several cloning vectors.

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Laine, M J; Nakhei, H; Dreier, J; Lehtilä, K; Meletzus, D; Eichenlaub, R; Metzler, M C

1996-01-01

In this paper we describe transformation of Clavibacter michiganensis subsp. sepedonicus, the potato ring rot bacterium, with plasmid vectors. Three of the plasmids used, pDM100, pDM302, and pDM306, contain the origin of replication from pCM1, a native plasmid of C. michiganensis subsp. michiganensis. We constructed two new cloning vectors, pHN205 and pHN216, by using the origin of replication of pCM2, another native plasmid of C. michiganensis subsp. michiganensis. Plasmids pDM302, pHN205, a...

A case of acute diarrhea due to the emerging pathogen Campylobacter jejuni subsp. doylei in Southern Chile Um caso de diarréia aguda devido ao patógeno emergente Campylobacter jejuni subsp. doylei no sul do Chile

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Heriberto Fernández

2003-04-01

Full Text Available The first documented case of acute diarrhea due to C. jejuni subsp. doylei in Chile is reported. The clinical findings, the absence of other enteropathogens, virus or parasites and the fact that C. jejuni subsp. doylei was the only bacteria isolated support the assumption that it was the etiological agent of this diarrheal case.O primeiro caso documentado de diarréia aguda por C. jejuni subsp. doylei no sul do Chile é apresentado. As características clínicas, a ausência de outros enteropatógenos, vírus ou parasitas, e o fato de C. jejuni subsp. doylei ter sido a única bactéria isolada, permitem assumir que este microrganismo é o agente etiológico neste caso de diarréia.

Salmonella enterica suppresses Pectobacterium carotovorum subsp. carotovorum population and soft rot progression by acidifying the microaerophilic environment.

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Kwan, Grace; Charkowski, Amy O; Barak, Jeri D

2013-02-12

Although enteric human pathogens are usually studied in the context of their animal hosts, a significant portion of their life cycle occurs on plants. Plant disease alters the phyllosphere, leading to enhanced growth of human pathogens; however, the impact of human pathogens on phytopathogen biology and plant health is largely unknown. To characterize the interaction between human pathogens and phytobacterial pathogens in the phyllosphere, we examined the interactions between Pectobacterium carotovorum subsp. carotovorum and Salmonella enterica or Escherichia coli O157:H7 with regard to bacterial populations, soft rot progression, and changes in local pH. The presence of P. carotovorum subsp. carotovorum enhanced the growth of both S. enterica and E. coli O157:H7 on leaves. However, in a microaerophilic environment, S. enterica reduced P. carotovorum subsp. carotovorum populations and soft rot progression by moderating local environmental pH. Reduced soft rot was not due to S. enterica proteolytic activity. Limitations on P. carotovorum subsp. carotovorum growth, disease progression, and pH elevation were not observed on leaves coinoculated with E. coli O157:H7 or when leaves were coinoculated with S. enterica in an aerobic environment. S. enterica also severely undermined the relationship between the phytobacterial population and disease progression of a P. carotovorum subsp. carotovorum budB mutant defective in the 2,3-butanediol pathway for acid neutralization. Our results show that S. enterica and E. coli O157:H7 interact differently with the enteric phytobacterial pathogen P. carotovorum subsp. carotovorum. S. enterica inhibition of soft rot progression may conceal a rapidly growing human pathogen population. Whereas soft rotted produce can alert consumers to the possibility of food-borne pathogens, healthy-looking produce may entice consumption of contaminated vegetables. Salmonella enterica and Escherichia coli O157:H7 may use plants to move between animal

Improvement of DNA transfer frequency and transposon mutagenesis of Erwinia carotovora subsp. betavasculorum.

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Rella, M; Axelrood, P E; Weinhold, A R; Schroth, M N

1989-01-01

The production of antibiotics and their role in microbial competition under natural conditions can be readily studied by the use of transposon mutants. Several antibiotic-producing strains of Erwinia carotovora subsp. betavasculorum were unable to accept foreign DNA. A plasmid delivery system was developed, using ethyl methanesulfonate mutagenesis, which entailed isolating E. carotovora subsp. betavasculorum mutants able to accept foreign DNA and transfer it to other strains. This enabled tra...

Characteristics of the Leuconostoc mesenteroides subsp. mesenteroides strains from fresh vegetables

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Dimić Gordana R.

2006-01-01

Full Text Available Strains synthesizing extracellular polysaccharide dextran on a medium with 10% sucrose were isolated from different kind of vegetables (cabbage, cucumber, cauliflower, kohlrabi, carrot, green beans, red beet, pepper, eggplant, radish. Carbohydrate fermentation was examined using a bioMerieux API 50 CHL test system. Among micropopulations with characteristic spherical cell morphology, 94.9% belonged to Leuconostoc mesenteroides subsp. mesenteroides and 5.1% were identified as Leuconostoc mesenteroides subsp. dextranicum. According to fermentation of pentoses L. mesenteroides strains were divided into three groups with a certain number of biotypes; 10 strains were tested on acid production. .

The effect on lactic fermentation of concentrating inert material with immobilised cells in a calcium alginate biocatalyser

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Juan Carlos Serrato

2005-05-01

Full Text Available Colombia is one of the world’s main sugarcane cultivating countries but it has not diversified its fermentation industry; a few fermentation industries produce alcohol and yeasts. Lactic acid and its derivatives then become alternatives providing added value to the sugar produced, thus benefiting the regions producing the sugar.This work evaluated the kinetics of lactic acid production using immobilised cells in calcium alginate at different concentrations of inert material. Lactobacillus delbrueckiI was the microorganism used and fermentation broth mainly consisted of sucrose and yeast exact. CSTR reactors were used without pH control. The results suggested that 2% to 3% inert material in the biocatalyst increased cellular retention and diffusiveness, leading to improved conversion and reaction rate.

Identification of Predominant Lactic Acid Bacteria and Yeasts of Turkish Sourdoughs and Selection of Starter Cultures for Liquid Sourdough Production Using Different Flours and Dough Yields

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Yağmur Gülten

2016-06-01

Full Text Available Eight samples of mature sourdough were collected from five provinces of Turkey. Lactic acid bacteria and yeasts were isolated and identified and used in different combinations to produce liquid sourdoughs. Microbiological and physicochemical characteristics of the experimental sourdoughs made with different flour types and dough yields were studied. The main lactic acid bacteria species identified were Lactobacillus (L. sanfranciscensis, Pediococcus pentosaceus, L. plantarum, L. namurencis, L. rossiae, Leuconostoc mesenteroides and L. zymae. L. spicheri, L. paralimentarius, L. mindensis, L. farciminis, L. acetotolerans, L. casei, Enterococcus faecium and Enterococcus durans were also found in sourdoughs at subdominant levels. Among yeasts, mainly Saccharomyces cerevisiae, but also Pichia guiliermondii and Torulaspora delbrueckii were the predominant species of yeasts identified in sourdoughs.