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Sample records for acid bacteria revisited

  1. Lactic Acid Bacteria

    ToddKlaenhammer

    2013-04-01

    Full Text Available Lactic acid bacteria (LAB are a diverse group of Gram-positive bacteria found in a vast array of environments including dairy products and the human gastrointestinal tract. In both niches, surface proteins play a crucial role in mediating interactions with the surrounding environment. The sortase enzyme is responsible for covalently coupling a subset of surface dependent proteins (SDPs to the cell wall of Gram-positive organisms through recognition of a conserved C-terminal LPXTG motif. Genomic sequencing of LAB and annotation has allowed for the identification of sortase and SDPs. Historically, sortase and SDPs were predominately investigated for their role in mediating pathogenesis. Identification of these proteins in LAB has shed light on their important roles in mediating nutrient acquisition through proteinase P as well as positive probiotic attributes including adhesion, mucus barrier function, and immune signaling. Furthermore, sortase expression signals in LAB have been exploited as a means to develop oral vaccines targeted to the gastrointestinal tract. In this review, we examine the collection of studies which evaluate sortase and SDPs in select species of dairy associated and health promoting LAB.

  2. LACTIC ACID BACTERIA: PROBIOTIC APPLICATIONS

    NEENA GARG

    2015-01-01

    Lactic acid bacteria (LAB) is a heterotrophic Gram-positive bacteria which under goes lactic acid fermentations and leads to production of lactic acid as an end product. LAB includes Lactobacillus, Leuconostoc, Pediococcus, Lactococcus and Streptococcus which are grouped together in the family lactobacillaceae. LAB shows numerous antimicrobial activities due to production of antibacterial and antifungal compounds such as organic acids, bacteriocins, diacetyl, hydrogen peroxide and reutrin. LA...

  3. LACTIC ACID BACTERIA: PROBIOTIC APPLICATIONS

    NEENA GARG

    2015-10-01

    Full Text Available Lactic acid bacteria (LAB is a heterotrophic Gram-positive bacteria which under goes lactic acid fermentations and leads to production of lactic acid as an end product. LAB includes Lactobacillus, Leuconostoc, Pediococcus, Lactococcus and Streptococcus which are grouped together in the family lactobacillaceae. LAB shows numerous antimicrobial activities due to production of antibacterial and antifungal compounds such as organic acids, bacteriocins, diacetyl, hydrogen peroxide and reutrin. LAB are used as starter culture, consortium members and bioprotective agents in food industry that improve food quality, safety and shelf life. A variety of probiotic LAB species are available including Lactobacillus acidophilus, L. bulgaricus, L. lactis, L. plantarum, L. rhamnosus, L. reuteri, L. fermentum, Bifidobacterium longum, B. breve, B. bifidum, B. esselnsis, B. lactis, B. infantis that are currently recommended for development of functional food products with health-promoting capacities.

  4. Engineering robust lactic acid bacteria

    Bron, P.A.; Bokhorst-van de Veen, van H.; Wels, M.; Kleerebezem, M.

    2011-01-01

    For centuries, lactic acid bacteria (LAB) have been industrially exploited as starter cultures in the fermentation of foods and feeds for their spoilage-preventing and flavor-enhancing characteristics. More recently, the health-promoting effects of LAB on the consumer have been widely acknowledged,

  5. Electron transport chains of lactic acid bacteria

    Brooijmans, R.J.W.

    2008-01-01

    Lactic acid bacteria are generally considered facultative anaerobic obligate fermentative bacteria. They are unable to synthesize heme. Some lactic acid bacteria are unable to form menaquinone as well. Both these components are cofactors of respiratory (electron transport) chains of prokaryotic bacteria. Lactococcus lactis, and several other lactic acid bacteria, however respond to the addition of heme in aerobic growth conditions. This response includes increased biomass and robustness. In t...

  6. Genetics of Lactic Acid Bacteria

    Zagorec, Monique; Anba-Mondoloni, Jamila; Coq, Anne-Marie Crutz-Le; Champomier-Vergès, Marie-Christine

    Many meat (or fish) products, obtained by the fermentation of meat originating from various animals by the flora that naturally contaminates it, are part of the human diet since millenaries. Historically, the use of bacteria as starters for the fermentation of meat, to produce dry sausages, was thus performed empirically through the endogenous micro-biota, then, by a volunteer addition of starters, often performed by back-slopping, without knowing precisely the microbial species involved. It is only since about 50 years that well defined bacterial cultures have been used as starters for the fermentation of dry sausages. Nowadays, the indigenous micro-biota of fermented meat products is well identified, and the literature is rich of reports on the identification of lactic acid bacteria (LAB) present in many traditional fermented products from various geographical origin, obtained without the addition of commercial starters (See Talon, Leroy, & Lebert, 2007, and references therein).

  7. Lactic Acid Bacteria in the Gut

    Stolaki, M.; Vos, de W.M.; Kleerebezem, M.; Zoetendal, E.G.

    2012-01-01

    From all bacterial groups, the lactic acid bacteria (LAB) are probably the group of bacteria that is most associated with human lifestyle. The term LAB mainly refers to the ability of these organisms to convert sugars to lactic acid. The LAB comprise non-sporing, aerotolerant, coccus or rod-shaped,

  8. Comparative genomics of the lactic acid bacteria

    Lactic acid-producing bacteria are associated with various plant and animal niches and play a key role in the production of fermented foods and beverages. We report nine genome sequences representing the phylogenetic and functional diversity of these bacteria. The small genomes of lactic acid bacter...

  9. Intramolecular Amide Hydrolysis in N-Methylmaleamic Acid Revisited

    2002-01-01

    The intramolecular amide hydrolysis of N-methylmaleamic acid have been revisited by use of density functional theory and inclusion of solvent effects. The results indicate that concerted reaction mechanism is favored over stepwise reaction mechanism. This is in agreement with the previous theoretical study. Sovlent effects have significant influence on the reaction barrier.

  10. Quorum sensing mechanism in lactic acid bacteria

    Hatice Yılmaz - Yıldıran

    2015-04-01

    and detection occurs as a consecution it is hard to understand their QS mechanism. In this review, connection between QS mechanism and some characteristics of lactic acid bacteria are evaluated such as concordance with its host, inhibition of pathogen development and colonization in gastrointestinal system, bacteriocin production, acid and bile resistance, adhesion to epithelium cells. Understanding QS mechanism of lactic acid bacteria will be useful to design metabiotics which is defined as novel probiotics.

  11. Genetics of proteinases of lactic acid bacteria

    Kok, Jan; Venema, Gerhardus

    1988-01-01

    Because it is essential for good growth with concomitant rapid acid production, and for the production of flavorous peptides and amino acids, the proteolytic ability of lactic acid bacteria is of crucial importance for reliable dairy product quality. In view of this importance, considerable research

  12. Acidophilic, Heterotrophic Bacteria of Acidic Mine Waters

    Wichlacz, Paul L.; Unz, Richard F.

    1981-01-01

    Obligately acidophilic, heterotrophic bacteria were isolated both from enrichment cultures developed with acidic mine water and from natural mine drainage. The bacteria were grouped by the ability to utilize a number of organic acids as sole carbon sources. None of the strains were capable of chemolithotrophic growth on inorganic reduced iron and sulfur compounds. All bacteria were rod shaped, gram negative, nonencapsulated, motile, capable of growth at pH 2.6 but not at pH 6.0, catalase and ...

  13. Comparative genomics of the lactic acid bacteria

    Makarova, K.; Slesarev, A.; Wolf, Y.; Sorokin, A.; Mirkin, B.; Koonin, E.; Pavlov, A.; Pavlova, N.; Karamychev, V.; Polouchine, N.; Shakhova, V.; Grigoriev, I.; Lou, Y.; Rokhsar, D.; Lucas, S.; Huang, K.; Goodstein, D. M.; Hawkins, T.; Plengvidhya, V.; Welker, D.; Hughes, J.; Goh, Y.; Benson, A.; Baldwin, K.; Lee, J. -H.; Diaz-Muniz, I.; Dosti, B.; Smeianov, V; Wechter, W.; Barabote, R.; Lorca, G.; Altermann, E.; Barrangou, R.; Ganesan, B.; Xie, Y.; Rawsthorne, H.; Tamir, D.; Parker, C.; Breidt, F.; Broadbent, J.; Hutkins, R.; O' Sullivan, D.; Steele, J.; Unlu, G.; Saier, M.; Klaenhammer, T.; Richardson, P.; Kozyavkin, S.; Weimer, B.; Mills, D.

    2006-06-01

    Lactic acid-producing bacteria are associated with various plant and animal niches and play a key role in the production of fermented foods and beverages. We report nine genome sequences representing the phylogenetic and functional diversity of these bacteria. The small genomes of lactic acid bacteria encode a broad repertoire of transporters for efficient carbon and nitrogen acquisition from the nutritionally rich environments they inhabit and reflect a limited range of biosynthetic capabilities that indicate both prototrophic and auxotrophic strains. Phylogenetic analyses, comparison of gene content across the group, and reconstruction of ancestral gene sets indicate a combination of extensive gene loss and key gene acquisitions via horizontal gene transfer during the coevolution of lactic acid bacteria with their habitats.

  14. Amino Acid Decarboxylase Activity of Some Lactic Acid Bacteria

    Pelin ERTÜRKMEN; Turhan, İlkay; Öner, Zübeyde

    2015-01-01

    Microorganisms which have decarboxylase activity can form biogenic amine by enzymatic decarboxylation of amino acids in foods. Histamine poisoning results from consumption of foods typically certain types of fish and cheeses that contain unusually high levels of histamine. Therefore, decarboxylase activity is an important problem at the selection of lactic acid bacteria as a starter culture in fermented products. In this study, decarboxylase activities of 161 lactic acid bacteria (LAB) strain...

  15. Study of fatty acid-bacteria interactions

    Complete text of publication follows. During our work we investigated fatty acid-bacteria interactions. The antibacterial property of fatty acids was reported by several authors. Despite of them there is not reassuring explanation about the mechanism of the antibacterial activity of these compounds. An effect can considerably change in case of different structured fatty acids. Our earlier studies conduct that small changes in the structures can modify changes in their behavior towards bacteria. The stearic acid does not cause any antibacterial effects during the first few hours of the investigation, may even help the bacterial growth. However, linolic acid (C18:2) shows a strong antibacterial effect during the first hours. After 24 hours this effect wears out and the bacteria have adapted to the stress. We studied the antibacterial activity using direct bioautography. This method has the advantage to allow examining lipophilic compounds. The linoleic acid decomposes in time under different physiological conditions creating numerous oxidized molecules. This may be the reason of its antimicrobial effect. For studying this phenomenon we used infrared and mass spectroscopic methods. We applied infrared spectroscopy for indicating any changes in the spectra of the fatty acids after the interaction of fatty acids with bacteria. So we are able to deduct on what could happen during these process. We paid great attention towards the changes of double bonds, on methylation and demethylation processes. Using mass spectroscopy we searched for oxidized products that may play important role in this process. These studies are only part of our more widespreading investigations, dealing with the antimicrobial properties of fatty acids.

  16. Acid resistance in enteric bacteria.

    Gorden, J; Small, P L

    1993-01-01

    Shigella species require a uniquely small inoculum for causing dysentery. One explanation for the low infective dose is that Shigella species are better able to survive the acidic conditions encountered in the stomach than are other enteric pathogens. We have tested Shigella species, Escherichia coli, and Salmonella species for the ability to survive at pH 2.5 for at least 2 h. Most isolates of Shigella and E. coli survived this treatment, whereas none of the Salmonella isolates were able to ...

  17. Discovering lactic acid bacteria by genomics

    Klaenhammer, T; Altermann, E; Arigoni, F; Bolotin, A; Breidt, F; Broadbent, J; Cano, R; Chaillou, S; Deutscher, J; Gasson, M; van de Guchte, M; Guzzo, J; Hartke, A; Hawkins, T; Hols, P; Hutkins, R; Kleerebezem, M; Kok, J; Kuipers, O; Maguin, E; McKay, L; Mills, D; Nauta, A; Overbeek, R; Pel, H; Pridmore, D; Saier, M; van Sinderen, D; Sorokin, A; Steele, J; O'Sullivan, D; de Vos, W; Weimer, B; Zagorec, M; Siezen, R

    2002-01-01

    This review summarizes a collection of lactic acid bacteria that are now undergoing genomic sequencing and analysis. Summaries are presented on twenty different species, with each overview discussing the organisms fundamental and practical significance, environmental habitat, and its role in ferment

  18. Bacteriocins From Lactic Acid Bacteria: Interest For Food Products Biopreservation

    Dortu, C.; Thonart, Philippe

    2009-01-01

    Bacteriocins from lactic acid bacteria: interest for food products biopreservation. Bacteriocins from lactic acid bacteria are low molecular weight antimicrobial peptides. They have inhibitory activity against the bacteria that are closed related to the producer strains and a narrow inhibitory spectrum. Nevertheless, most of them have activity against some food-born pathogenic bacteria as Listeria monocytogenes. The application of bacteriocins or bacteriocin producing lactic acid bacteria in ...

  19. Freeze-drying of lactic acid bacteria.

    Fonseca, Fernanda; Cenard, Stéphanie; Passot, Stéphanie

    2015-01-01

    Lactic acid bacteria are of great importance for the food and biotechnology industry. They are widely used as starters for manufacturing food (e.g., yogurt, cheese, fermented meats, and vegetables) and probiotic products, as well as for green chemistry applications. Freeze-drying or lyophilization is a convenient method for preservation of bacteria. By reducing water activity to values below 0.2, it allows long-term storage and low-cost distribution at suprazero temperatures, while minimizing losses in viability and functionality. Stabilization of bacteria via freeze-drying starts with the addition of a protectant solution to the bacterial suspension. Freeze-drying includes three steps, namely, (1) freezing of the concentrated and protected cell suspension, (2) primary drying to remove ice by sublimation, and (3) secondary drying to remove unfrozen water by desorption. In this chapter we describe a method for freeze-drying of lactic acid bacteria at a pilot scale, thus allowing control of the process parameters for maximal survival and functionality recovery. PMID:25428024

  20. Food preservation using antifungal lactic acid bacteria

    Crowley, Sarah Catherine Mary

    2013-01-01

    Fungal spoilage of food and feed prevails as a major problem for the food industry. The use antifungal-producing lactic acid bacteria (LAB) may represent a safer, natural alternative to the use of chemical preservatives in foods. A large scale screen was undertaken to identify a variety of LAB with antifungal properties from plant, animal and human sources. A total of 6,720 LAB colonies were isolated and screened for antifungal activity against the indicator Penicillium expansum. 94 broad-spe...

  1. Biosynthesis of myristic acid in luminescent bacteria

    In vivo pulse-label studies have demonstrated that luminescent bacteria can provide myritic acid (14:0) required for the synthesis of the luciferase substrate myristyl aldehyde. Luminescent wild type Vibrio harveyi incubated with [14C] acetate in a nutrient-depleted medium accumulated substantial tree [14C]fatty acid (up to 20% of the total lipid label). Radio-gas chromatography revealed that > 75% of the labeled fatty acid is 14:0. No free fatty acid was detected in wild type cells labeled prior to the development of bioluminescence in the exponential growth phase, or in a dark mutant of V. harveyi (mutant M17) that requires exogenous 14:0 for light emission. The preferential accumulation of 14:0 was not observed when wild type cells were labeled with [14C]acetate in regular growth medium. Moreover, all V. harveyi strains exhibited similar fatty acid mass compositions regardless of the state of bioluminescence. Since earlier work has shown that a luminescence-related acyltransferase (defective in the M17 mutant) can catalyze the deacylation of fatty acyl-acyl carrier protein in vitro, the present results are consistent with a model in which this enzyme diverts 14:0 to the luminescence system during fatty acid biosynthesis. Under normal conditions, the supply of 14:0 by this pathway is tightly regulated such that bioluminescence development does not significantly alter the total fatty acid composition

  2. IDENTIFICATION OF INDUSTRIALLY IMPORTANT LACTIC ACID BACTERIA IN FOODSTUFFS

    Prosekov, A.; Babich, O.; Bespomestnykh, K.

    2013-01-01

    Universal genus-specific primers for comparative analysis of two aligned 16S rRNA gene nucleotide sequences of lactic acid bacteria were constructed. The method to identify lactic acid bacteria and a comprehensive plan for their genus and species identification may be used to characterize isolated strains of the Lactobacillus genus bacteria and in quality control of foodstuffs enriched with Lactobacillus.

  3. The effect of lactic acid bacteria on cocoa bean fermentation.

    Ho, Van Thi Thuy; Zhao, Jian; Fleet, Graham

    2015-07-16

    Cocoa beans (Theobroma cacao L.) are the raw material for chocolate production. Fermentation of cocoa pulp by microorganisms is crucial for developing chocolate flavor precursors. Yeasts conduct an alcoholic fermentation within the bean pulp that is essential for the production of good quality beans, giving typical chocolate characters. However, the roles of bacteria such as lactic acid bacteria and acetic acid bacteria in contributing to the quality of cocoa bean and chocolate are not fully understood. Using controlled laboratory fermentations, this study investigated the contribution of lactic acid bacteria to cocoa bean fermentation. Cocoa beans were fermented under conditions where the growth of lactic acid bacteria was restricted by the use of nisin and lysozyme. The resultant microbial ecology, chemistry and chocolate quality of beans from these fermentations were compared with those of indigenous (control) fermentations. The yeasts Hanseniaspora guilliermondii, Pichia kudriavzevii, Kluyveromyces marxianus and Saccharomyces cerevisiae, the lactic acid bacteria Lactobacillus plantarum, Lactobacillus pentosus and Lactobacillus fermentum and the acetic acid bacteria Acetobacter pasteurianus and Gluconobacter frateurii were the major species found in control fermentations. In fermentations with the presence of nisin and lysozyme, the same species of yeasts and acetic acid bacteria grew but the growth of lactic acid bacteria was prevented or restricted. These beans underwent characteristic alcoholic fermentation where the utilization of sugars and the production of ethanol, organic acids and volatile compounds in the bean pulp and nibs were similar for beans fermented in the presence of lactic acid bacteria. Lactic acid was produced during both fermentations but more so when lactic acid bacteria grew. Beans fermented in the presence or absence of lactic acid bacteria were fully fermented, had similar shell weights and gave acceptable chocolates with no differences

  4. Probiotic Lactic Acid Bacteria and Skin Health.

    Jeong, Ji Hye; Lee, Chang Y; Chung, Dae Kyun

    2016-10-25

    Human skin is the first defense barrier against the external environment, especially microbial pathogens and physical stimulation. Many studies on skin health with Lactic acid bacteria (LAB) have been published for many years, including prevention of skin disease and improvement of skin conditions. LAB, a major group of gram-positive bacteria, are known to be beneficial to human health by acting as probiotics. Recent studies have shown that LAB and their extracts have beneficial effects on maintenance and improvement of skin health. Oral administration of Lactobacillus delbrueckii inhibits the development of atopic disease. In addition, LAB and LAB extracts are known to have beneficial effects on intestinal diseases, with Lactobacillus plantarum having been shown to attenuate IL-10 deficient colitis. In addition to intestinal health, L. plantarum also has beneficial effects on skin. pLTA, which is lipoteichoic acid isolated from L. plantarum, has anti-photoaging effects on human skin cells by regulating the expression matrix meralloprotionase-1 (MMP-1) expression. While several studies have proposed a relationship between diseases of the skin and small intestines, there are currently no published reviews of the effects of LAB for skin health through regulation of intestinal conditions and the immune system. In this review, we discuss recent findings on the effects of LAB on skin health and its potential applications in beauty foods. PMID:26287529

  5. Functional genomics of lactic acid bacteria: from food to health

    Douillard, F.P.; Vos, de, W.M.

    2014-01-01

    Genome analysis using next generation sequencing technologies has revolutionized the characterization of lactic acid bacteria and complete genomes of all major groups are now available. Comparative genomics has provided new insights into the natural and laboratory evolution of lactic acid bacteria and their environmental interactions. Moreover, functional genomics approaches have been used to understand the response of lactic acid bacteria to their environment. The results have been instrumen...

  6. Selection of lactic acid bacteria able to ferment inulin hydrolysates

    Octavian BASTON; Oana Emilia CONSTANTIN

    2012-01-01

    Eight homofermentative lactic acid bacteria isolates were tested for lactic acid production using chicory and Jerusalem artichoke hydrolysate as substrate. The pH, lactic acid yield and productivity were used to select the best homolactic bacteria for lactic acid production. The selected strains produced lactic acid at maximum yield after 24 hours of fermentation and the productivity was greater at 24 hours of fermentation. From all studied strains, Lb1 and Lb2 showed the best results regardi...

  7. Towards lactic acid bacteria-based biorefineries.

    Mazzoli, Roberto; Bosco, Francesca; Mizrahi, Itzhak; Bayer, Edward A; Pessione, Enrica

    2014-11-15

    Lactic acid bacteria (LAB) have long been used in industrial applications mainly as starters for food fermentation or as biocontrol agents or as probiotics. However, LAB possess several characteristics that render them among the most promising candidates for use in future biorefineries in converting plant-derived biomass-either from dedicated crops or from municipal/industrial solid wastes-into biofuels and high value-added products. Lactic acid, their main fermentation product, is an attractive building block extensively used by the chemical industry, owing to the potential for production of polylactides as biodegradable and biocompatible plastic alternative to polymers derived from petrochemicals. LA is but one of many high-value compounds which can be produced by LAB fermentation, which also include biofuels such as ethanol and butanol, biodegradable plastic polymers, exopolysaccharides, antimicrobial agents, health-promoting substances and nutraceuticals. Furthermore, several LAB strains have ascertained probiotic properties, and their biomass can be considered a high-value product. The present contribution aims to provide an extensive overview of the main industrial applications of LAB and future perspectives concerning their utilization in biorefineries. Strategies will be described in detail for developing LAB strains with broader substrate metabolic capacity for fermentation of cheaper biomass. PMID:25087936

  8. Antifungal Activity of Selected Lactic Acid Bacteria and Propionic Acid Bacteria against Dairy-Associated Spoilage Fungi

    Aunsbjerg, Stina Dissing

    Bacterial cultures of lactic and propionic acid bacteria are widely used in fermented products including dairy products. Spoilage fungi may constitute a quality and safety issue in these products. The antifungal properties of some lactic and propionic acid bacteria make them potential candidates...... metabolites produced. Besides diacetyl and lactic acid, 6 antifungal hydroxy acids were identified. Of these, 3 have previously been reported from antifungal lactic acid bacteria, whereas the other 3 hydroxy acids have not previously been reported produced by antifungal lactic acid bacteria....... for prolonging shelf-life of food without the addition of specific preservatives. Increased interest in the use of these bacteria for biopreservation has led to identification of a range of potent strains, and in addition, isolation and identification of various antifungal metabolites produced by...

  9. Stress Physiology of Lactic Acid Bacteria.

    Papadimitriou, Konstantinos; Alegría, Ángel; Bron, Peter A; de Angelis, Maria; Gobbetti, Marco; Kleerebezem, Michiel; Lemos, José A; Linares, Daniel M; Ross, Paul; Stanton, Catherine; Turroni, Francesca; van Sinderen, Douwe; Varmanen, Pekka; Ventura, Marco; Zúñiga, Manuel; Tsakalidou, Effie; Kok, Jan

    2016-09-01

    Lactic acid bacteria (LAB) are important starter, commensal, or pathogenic microorganisms. The stress physiology of LAB has been studied in depth for over 2 decades, fueled mostly by the technological implications of LAB robustness in the food industry. Survival of probiotic LAB in the host and the potential relatedness of LAB virulence to their stress resilience have intensified interest in the field. Thus, a wealth of information concerning stress responses exists today for strains as diverse as starter (e.g., Lactococcus lactis), probiotic (e.g., several Lactobacillus spp.), and pathogenic (e.g., Enterococcus and Streptococcus spp.) LAB. Here we present the state of the art for LAB stress behavior. We describe the multitude of stresses that LAB are confronted with, and we present the experimental context used to study the stress responses of LAB, focusing on adaptation, habituation, and cross-protection as well as on self-induced multistress resistance in stationary phase, biofilms, and dormancy. We also consider stress responses at the population and single-cell levels. Subsequently, we concentrate on the stress defense mechanisms that have been reported to date, grouping them according to their direct participation in preserving cell energy, defending macromolecules, and protecting the cell envelope. Stress-induced responses of probiotic LAB and commensal/pathogenic LAB are highlighted separately due to the complexity of the peculiar multistress conditions to which these bacteria are subjected in their hosts. Induction of prophages under environmental stresses is then discussed. Finally, we present systems-based strategies to characterize the "stressome" of LAB and to engineer new food-related and probiotic LAB with improved stress tolerance. PMID:27466284

  10. Fermentation of Fructooligosaccharides by Lactic Acid Bacteria and Bifidobacteria†

    Kaplan, Handan; Hutkins, Robert W.

    2000-01-01

    Lactic acid bacteria and bifidobacteria were screened of their ability to ferment fructooligosaccharides (FOS) on MRS agar. Of 28 strains of lactic acid bacteria and bifidobacteria examined, 12 of 16 Lactobacillus strains and 7 of 8 Bifidobacterium strains fermented FOS. Only strains that gave a positive reaction by the agar method reached high cell densities in broth containing FOS.

  11. Functional genomics of lactic acid bacteria: from food to health

    Douillard, F.P.; Vos, de W.M.

    2014-01-01

    Genome analysis using next generation sequencing technologies has revolutionized the characterization of lactic acid bacteria and complete genomes of all major groups are now available. Comparative genomics has provided new insights into the natural and laboratory evolution of lactic acid bacteria a

  12. Antibiotic resistance of lactic acid bacteria

    Bulajić Snežana

    2008-01-01

    Full Text Available Knowledge on the antibiotic resistance of lactic acid bacteria is still limited, possibly because of the large numbers of genera and species encountered in this group, as well as variances in their resistance spectra. The EFSA considers antibiotic resistances, especially transferable resistances, an important decision criterion for determining a strain's QPS status. There are no approved standards for the phenotypic or genotypic evaluation of antibiotic resistances in food isolates. Also, the choice of media is problematic, as well as the specification of MIC breakpoint values as a result of the large species variation and the possible resulting variation in MIC values between species and genera. The current investigations in this field showed that we might end up with a range of different species- or genus-specific breakpoint values that may further increase the current complexity. Another problem associated with safety determinations of starter strains is that once a resistance phenotype and an associated resistance determinant have been identified, it becomes difficult to show that this determinant is not transferable, especially if the resistance gene is not located on a plasmid and no standard protocols for showing genetic transfer are available. Encountering those problems, the QPS system should allow leeway for the interpretations of results, especially when these relate to the methodology for resistance phenotype determinations, determinations of MIC breakpoints for certain genera, species, or strains, the nondeterminability of a genetic basis of a resistance phenotype and the transferability of resistance genes.

  13. Lactic Acid Bacteria Differentially Activate Natural Killer Cells

    Fink, Lisbeth Nielsen; Christensen, Hanne Risager; Frøkiær, Hanne

    antigen presenting cells and T-cells. Bacteria translocating across the gastrointestinal mucosa are presumed to gain access to NK cell compartments, as consumption of certain strains of lactic acid bacteria has been shown to increase in vivo NK cytotoxic activity. On-going research in our lab aims at...... describing strain-dependent effects of lactic acid bacteria on regulatory functions of NK-cells. Here, we have investigated how human gut flora-derived non-pathogenic lactic acid bacteria affect NK cells in vitro, by measuring proliferation and IFN-gamma production of human peripheral blood NK cells upon...... bacterial stimulation. Methods: CD3-CD56+ NK cells were isolated from buffy coats by negative isolation using a lineage specific antibody cocktail and magnetic beads binding the labelling antibodies on non-NK cells. NK cells were incubated either with 10 microg/ml UV-inactivated lactic acid bacteria or 10...

  14. COMPARISON OF OCCURENCE LACTIC ACID BACTERIA IN CHOSEN YOGURTS

    Silvia Pinterová

    2010-11-01

    Full Text Available The yogurt is healthy food, which contains at least 100 million cultures per gram. Probiotic bacteria have been proven to reduce the effects of some gastrointestinal problems, probiotics can greatly reduce lactose intolerance, have also been proven to prevent colon cancers, there are also a natural immune system booster. In our research we detected numbers of lactid acid bacteria in yogurts in slovak market. There were classical yogurts, yogurts with probiotics, yogurts with fat and non fat. We numbered lactid acid bacteria from and after expiration, in agars MRS and Lee´s. In examined yogurts we detected from expiration from 78.107  to 169.107  and after expiration from 59.107 to 133.107 lactic acid bacteria in 1 ml of yogurt. In agreement with Food Codex of SR (2010 of rules all these yogurts satisfy number of lactid acid bacteria. doi:10.5219/31

  15. The impact of lactic acid bacteria on sourdough fermentation

    Savić Dragiša S.; Joković Nataša

    2005-01-01

    The baking of sourdough breads represents one of the oldest biotechnological processes. Despite traditionality, sourdough bread has great potential because of its benefits. Sourdough is a mixture of flour and water that is dominated by a complex microflora composed of yeasts and lactic acid bacteria that are crucial in the preparation of bread dough. Lactic acid bacteria cause acidification by producing lactic acid that increases the shelf life of bread by preventing the growth of undesirable...

  16. Quorum sensing mechanism in lactic acid bacteria

    Hatice Yılmaz - Yıldıran; Aynur Gül Karahan; Gülden Başyiğit - Kılıç

    2015-01-01

    For a long time, microorganisms were considered as just multiplying, finding nutrients and living by themselves organisms. But that belief changed 50 years ago along with the discovery of bacteria communication with each other and environment by microbiologists. The language used in the communication consists of signal molecules and these molecules are generally called 'auto inducer'. Bacteria are capable of measuring density of these molecules and by this way they are able to detect amoun...

  17. Interaction of neptunium with humic acid and anaerobic bacteria

    Humic acid and bacteria play an important role in the migration of radionuclides in groundwaters. The interaction of neptunium with humic acid and anaerobic bacteria has been investigated by liquid/liquid and solid/liquid extraction systems. For liquid/liquid extraction, the apparent complex formation constant, βα was obtained from the distribution between two phases of neptunium. For solid/liquid extraction, the ratio of sorption to bacteria, Kd, was measured. Kd of humic acid can be evaluated from βα. The large value of βα and Kd means strong interaction of neptunium with organisms. In order to examine the effect of the nature of organism on interaction, the interaction with humic acid was compared to that with non-sterilized or sterilized mixed anaerobic bacteria. The value of βα of humate depended on neptunium ion concentration as well as pH, which showed the effect of polyelectrolyte properties and heterogeneous composition of humic acid. The comparison of interaction with humic acid and bacteria indicated that the Kd value of humic acid was larger than that of bacteria and more strongly depend on pH. (author)

  18. Production of Value-added Products by Lactic Acid Bacteria

    Lactic acid bacteria (LAB) are a group of facultative anaerobic, catalase negative, nonmotile and nonsporeforming–Gram positive bacteria. Most LAB utilize high energy C sources including monomer sugars to produce energy to maintain cellular structure and function. This anaerobic fermentation proce...

  19. Inhibition of seafood-borne bacteria in cooked mackerel (Rastrelliger kanagurta) fish meat by lactic acid bacteria

    Kanappan, S.; G. Gopikrishna

    2008-01-01

    Antagonistic activity of lactic acid bacteria (LAB) namely Streptococcus faecalis, Pediococcus cerevisiae and Lactobacillus casei was tested against seafood-borne bacteria such as Staphylococcus aureus, Bacillus cereus, Escherichia coli, Clostridium perfringens and Listeria monocytogenes. Three lactic acid bacteria such as Streptococcus faecalis, Lactobacillus casei and Pediococcus cerevisiae were coated on cooked mackerel meat, individually and in combination against fish-borne bacteria. S. ...

  20. DNA fingerprinting of lactic acid bacteria in sauerkraut fermentations

    Previous studies using traditional biochemical methods to study the ecology of commercial sauerkraut fermentations revealed that four lactic acid bacteria species, Leuconostoc mesenteroides, Lactobacillus plantarum, Pediococcus pentosaceus, and Lactobacillus brevis were the primary microorganisms in...

  1. Cell wall structure and function in lactic acid bacteria

    Kulakauskas, Saulius

    2014-01-01

    The cell wall of Gram-positive bacteria is a complex assemblage of glycopolymers and proteins. It consists of a thick peptidoglycan sacculus that surrounds the cytoplasmic membrane and that is decorated with teichoic acids, polysaccharides, and proteins. It plays a major role in bacterial physiology since it maintains cell shape and integrity during growth and division; in addition, it acts as the interface between the bacterium and its environment. Lactic acid bacteria (LAB) are traditionall...

  2. Controlled overproduction of proteins by lactic acid bacteria

    Kuipers, Oscar P; Ruyter, Pascalle G.G.A. de; Kleerebezem, Michiel; de Vos, Willem M

    1997-01-01

    Lactic acid bacteria are widely used in industrial food fermentations, contributing to flavour, texture and preservation of the fermented products. Here we describe recent advances in the development of controlled gene expression systems, which allow the regulated overproduction of any desirable protein by lactic acid bacteria. Some systems benefit from the fact that the expression vectors, marker genes and inducing factors can be used directly in food applications since they are all derived ...

  3. Flow cytometric assessment of viability of lactic acid bacteria

    Bunthof, C.J.; Bloemen, K.; Breeuwer, P.; Rombouts, F. M.; Abee, T

    2001-01-01

    The viability of lactic acid bacteria is crucial for their applications as dairy starters and as probiotics. We investigated the usefulness of flow cytometry (FCM) for viability assessment of lactic acid bacteria. The esterase substrate carboxyfluorescein diacetate (cFDA) and the dye exclusion DNA binding probes propidium iodide (PI) and TOTO-1 were tested for live/dead discrimination using a Lactococcus, a Streptococcus, three Lactobacillus, two Leuconostoc, an Enterococcus, and a Pediococcu...

  4. The impact of lactic acid bacteria on sourdough fermentation

    Savić Dragiša S.

    2005-01-01

    Full Text Available The baking of sourdough breads represents one of the oldest biotechnological processes. Despite traditionality, sourdough bread has great potential because of its benefits. Sourdough is a mixture of flour and water that is dominated by a complex microflora composed of yeasts and lactic acid bacteria that are crucial in the preparation of bread dough. Lactic acid bacteria cause acidification by producing lactic acid that increases the shelf life of bread by preventing the growth of undesirable microorganisms and affects the nutritional value of bread by increasing the availability of minerals. In addition to these advantages, the use of sourdough fermentation also improves dough machinability, breadcrumb structure and the characteristic flavour of bread. Lactic acid bacteria in sourdough fermentation are well known representing both homofermentative and heterofermentative bacteria. They may originate from selected natural contaminants in the flour or from a starter culture containing one or more known species of lactic acid bacteria. Sourdough can be cultivated in bakeries or obtained from commercial suppliers. However, many bakeries in Europe still use spontaneously fermented sourdoughs, which have been kept metabolically active for decades by the addition of flour and water at regular intervals. The impact of lactic acid bacteria on sourdough fermentation and their influence on dough and bread quality was discussed on the basis of research and literature data.

  5. Effects of Lactic Acid Bacteria Inoculated Fermentation on Pickled Cucumbers

    Xiaoyi Ji; Yuan Wu; Xingzhu Wu; Yonghua Lin; Weiwei Xu; Hui Ruan; Guoqing He

    2013-01-01

    The aim of this study was to determine the effects of Lactic Acid Bacteria (LAB) fermentation on the texture and organic acid of pickled cucumbers. Texture and sensory evaluation as well as a microscopic observation were performed to study the textural differences among fresh cucumber, Spontaneous fermentation (SF) cucumber and LAB Inoculating Fermentation (LABIF) cucumber. Accumulation of seven organic acids i.e., oxalic, tartaric, malic, lactic, acetic, citric and succinic acid during cucum...

  6. Making More of Milk Sugar by Engineering Lactic Acid Bacteria

    Vos, Willem M. de; Hols, Pascal; Kranenburg, Richard van; Luesink, Evert; Kuipers, Oscar P.; Oost, John van der; Kleerebezem, Michiel; Hugenholtz, Jeroen

    1998-01-01

    By exploiting their genetic and metabolic capacity, lactic acid bacteria can be used to generate a variety of products from milk sugar lactose other than the archetypical lactic acid. This review will outline the different genetic and metabolic engineering strategies that can be applied to lactic ac

  7. Remediation of Acid Mine Drainage with Sulfate Reducing Bacteria

    Hauri, James F.; Schaider, Laurel A.

    2009-01-01

    Sulfate reducing bacteria have been shown to be effective at treating acid mine drainage through sulfide production and subsequent precipitation of metal sulfides. In this laboratory experiment for undergraduate environmental chemistry courses, students design and implement a set of bioreactors to remediate acid mine drainage and explain observed…

  8. Lactic acid bacteria from fresh fruit and vegetables as biocontrol agents of phytopathogenic bacteria and fungi

    Trias Mansilla, Rosalia; Bañeras Vives, Lluís; Montesinos Seguí, Emilio; Badosa Romañó, Esther

    2008-01-01

    This study evaluated the efficacy of lactic acid bacteria (LAB) isolated from fresh fruits and vegetables as biocontrol agents against the phytopathogenic and spoilage bacteria and fungi, Xanthomonas campestris, Erwinia carotovora, Penicillium expansum, Monilinia laxa, and Botrytis cinerea. The antagonistic activity of 496 LAB strains was tested in vitro and all tested microorganisms except P. expansum were inhibited by at least one isolate. The 496 isolates were also analyzed for the inhibit...

  9. Comparative functional genomics of amino acid metabolism of lactic acid bacteria

    Pastink, M.I.

    2009-01-01

    The amino acid metabolism of lactic acid bacteria used as starters in industrial fermentations has profound effects on the quality of the fermented foods. The work described in this PhD thesis was initiated to use genomics technologies and a comparative approach to link the gene content of some well-known lactic acid bacteria to flavor formation and to increase our general knowledge in the area of amino acid metabolism. The three well-known lactic acid bacteria that were used in these studies...

  10. Fatty acid composition of cream fermented by probiotic bacteria

    Lutfiye Yilmaz-Ersan

    2013-01-01

    The production of fatty acids in cream containing one of the three probiotic microorganisms (Bifidobacterium lactis, Lactobacillus acidophilus and Lactobacillus rhamnosus) was evaluated at 4±1 °C for up to 15 days. Gas chromatographic analysis of the fatty acid content showed that during storage the amount of linoleic and α-linolenic acids increased in the probiotic cream fermented with B. lactis compared to the control cream. Probiotic bacteria were all associated with increases in medium ch...

  11. Clostridium sticklandii, a specialist in amino acid degradation:revisiting its metabolism through its genome sequence

    Pelletier Eric

    2010-10-01

    Full Text Available Abstract Background Clostridium sticklandii belongs to a cluster of non-pathogenic proteolytic clostridia which utilize amino acids as carbon and energy sources. Isolated by T.C. Stadtman in 1954, it has been generally regarded as a "gold mine" for novel biochemical reactions and is used as a model organism for studying metabolic aspects such as the Stickland reaction, coenzyme-B12- and selenium-dependent reactions of amino acids. With the goal of revisiting its carbon, nitrogen, and energy metabolism, and comparing studies with other clostridia, its genome has been sequenced and analyzed. Results C. sticklandii is one of the best biochemically studied proteolytic clostridial species. Useful additional information has been obtained from the sequencing and annotation of its genome, which is presented in this paper. Besides, experimental procedures reveal that C. sticklandii degrades amino acids in a preferential and sequential way. The organism prefers threonine, arginine, serine, cysteine, proline, and glycine, whereas glutamate, aspartate and alanine are excreted. Energy conservation is primarily obtained by substrate-level phosphorylation in fermentative pathways. The reactions catalyzed by different ferredoxin oxidoreductases and the exergonic NADH-dependent reduction of crotonyl-CoA point to a possible chemiosmotic energy conservation via the Rnf complex. C. sticklandii possesses both the F-type and V-type ATPases. The discovery of an as yet unrecognized selenoprotein in the D-proline reductase operon suggests a more detailed mechanism for NADH-dependent D-proline reduction. A rather unusual metabolic feature is the presence of genes for all the enzymes involved in two different CO2-fixation pathways: C. sticklandii harbours both the glycine synthase/glycine reductase and the Wood-Ljungdahl pathways. This unusual pathway combination has retrospectively been observed in only four other sequenced microorganisms. Conclusions Analysis of the C

  12. Food-grade Selection Markers in Lactic Acid Bacteria

    Song He; Fanghong Gong; Ya'nan Guo; Dechun Zhang.

    2012-01-01

    Lactic acid bacteria (LAB) are generally regarded as safe (GRAS) microorganisms and widely used in industry and medicine. We are trying to add additional properties to them by gene engineering. However, the genetically modified bacteria are not acceptable to use in food and medicine due to the presence of antibiotic resistance genes in plasmids. Thus, it is necessary to develop food-grade selection markers. Food-grade markers can be divided into three classes based on their selected character...

  13. Selection of lactic acid bacteria able to ferment inulin hydrolysates

    Octavian BASTON

    2012-12-01

    Full Text Available Eight homofermentative lactic acid bacteria isolates were tested for lactic acid production using chicory and Jerusalem artichoke hydrolysate as substrate. The pH, lactic acid yield and productivity were used to select the best homolactic bacteria for lactic acid production. The selected strains produced lactic acid at maximum yield after 24 hours of fermentation and the productivity was greater at 24 hours of fermentation. From all studied strains, Lb1 and Lb2 showed the best results regarding lactic acid yields andproductivity. After 48 hours of chicory and Jerusalem artichhoke hydrolysates fermentation, from all the studied strains, Lb2 produced the highest lactic acid yield (0.97%. Lb2 produced after 48 hours of fermentation the lowest pH value of 3.45±0.01. Lb2 showed greater lactic acid productivity compared to the other studied lactic acid bacteria, the highest values, 0.13 g·L-1·h-1fromJerusalem artichoke hydrolysate and 0.11g·L-1·h-1 from chicory hydrolysate, being produced after 24 hours of fermentation.

  14. Nucleotide Metabolism and its Control in Lactic Acid Bacteria

    Kilstrup, Mogens; Hammer, Karin; Jensen, Peter Ruhdal;

    2005-01-01

    Most metabolic reactions are connected through either their utilization of nucleotides or their utilization of nucleotides or their regulation by these metabolites. In this review the biosynthetic pathways for pyrimidine and purine metabolism in lactic acid bacteria are described including the...... interconversion pathways, the formation of deoxyribonucleotides and the salvage pathways for use of exogenous precursors. The data for the enzymatic and the genetic regulation of these pathways are reviewed, as well as the gene organizations in different lactic acid bacteria. Mutant phenotypes and methods for...... manipulation of nucleotide pools are also discussed. Our aim is to provide an overview of the physiology and genetics of nucleotide metabolism and its regulation that will facilitate the interpretation of data arising from genetics, metabolomics, proteomics, and transcriptomics in lactic acid bacteria....

  15. ldentification and Mutagenesis of Lactic Acid Bacteria from Chinese Sauerkraut

    Yajing CHAl; Hao SHl; Ri NA

    2015-01-01

    ln order to analyze the fermentation properties of lactic acid bacteria in Chinese sauerkraut and to improve acid production, 21 samples of Chinese sauerkraut from lnner Mongolia and Northeast China were col ected and isolated with a Man-Rogosa-Sharpe (MRS) culture. Sixteen strains of lactic acid bacteria were identified by combining both phenotype and genotype methods. After activation, the 16 strains were inoculated into the MRS medium with a concentration of 4%and then incubated at 37 ℃. The pH and the absorbance of the culture were mea-sured. The activated strains were then mutagenized in a field of 4 KV/cm mutation, with dosages administered within 20 minutes and 30 minutes, respectively. The variation curves of the pH and the absorbance of the culture were determined. The experimental results showed that the lactic acid bacteria isolated from the soup were identified as Lactobacil us and the acid production of the bacteria was signifi-cantly improved by the mutagenesis of the corona electric field.

  16. Acetic acid bacteria: A group of bacteria with versatile biotechnological applications.

    Saichana, Natsaran; Matsushita, Kazunobu; Adachi, Osao; Frébort, Ivo; Frebortova, Jitka

    2015-11-01

    Acetic acid bacteria are gram-negative obligate aerobic bacteria assigned to the family Acetobacteraceae of Alphaproteobacteria. They are members of the genera Acetobacter, Gluconobacter, Gluconacetobacter, Acidomonas, Asaia, Kozakia, Swaminathania, Saccharibacter, Neoasaia, Granulibacter, Tanticharoenia, Ameyamaea, Neokomagataea, and Komagataeibacter. Many strains of Acetobacter and Komagataeibacter have been known to possess high acetic acid fermentation ability as well as the acetic acid and ethanol resistance, which are considered to be useful features for industrial production of acetic acid and vinegar, the commercial product. On the other hand, Gluconobacter strains have the ability to perform oxidative fermentation of various sugars, sugar alcohols, and sugar acids leading to the formation of several valuable products. Thermotolerant strains of acetic acid bacteria were isolated in order to serve as the new strains of choice for industrial fermentations, in which the cooling costs for maintaining optimum growth and production temperature in the fermentation vessels could be significantly reduced. Genetic modifications by adaptation and genetic engineering were also applied to improve their properties, such as productivity and heat resistance. PMID:25485864

  17. Surface Binding of Aflatoxin B1 by Lactic Acid Bacteria

    Haskard, Carolyn A.; El-Nezami, Hani S.; Kankaanpää, Pasi E.; Salminen, Seppo; Ahokas, Jorma T.

    2001-01-01

    Specific lactic acid bacterial strains remove toxins from liquid media by physical binding. The stability of the aflatoxin B1 complexes formed with 12 bacterial strains in both viable and nonviable (heat- or acid-treated) forms was assessed by repetitive aqueous extraction. By the fifth extraction, up to 71% of the total aflatoxin B1 remained bound. Nonviable bacteria retained the highest amount of aflatoxin B1. Lactobacillus rhamnosus strain GG (ATCC 53103) and L. rhamnosus strain LC-705 (DS...

  18. Effects of lactic acid bacteria contamination on lignocellulosic ethanol fermentation

    Slower fermentation rates, mixed sugar compositions, and lower sugar concentrations may make lignocellulosic fermentations more susceptible to contamination by lactic acid bacteria (LAB), which is a common and costly problem to the corn-based fuel ethanol industry. To examine the effects of LAB con...

  19. Mucosal Vaccination and Therapy with Genetically Modified Lactic Acid Bacteria

    Wells, J.

    2011-01-01

    Lactic acid bacteria (LAB) have proved to be effective mucosal delivery vehicles that overcome the problem of delivering functional proteins to the mucosal tissues. By the intranasal route, both live and killed LAB vaccine strains have been shown to elicit mucosal and systemic immune responses that

  20. Lactic acid bacteria in a changing legislative environment

    Feord, J.

    2002-01-01

    The benefits of using lactic acid bacteria in the food chain, both through direct consumption and production of ingredients, are increasingly recognised by the food industry and consumers alike. The regulatory environment surrounding these products is diverse, covering foods and food ingredients, pr

  1. Make use of lactic acid bacteria in biomass to biofuel

    Lactic acid bacteria (LAB) have been widely used in dairy fermentations, nutraceuticals, and probiotic/prebiotic applications. Selected strains from the LAB could potentially be used as microbial catalysts for production of fuels and chemicals from lignocellulosic biomass. The unique traits of lac...

  2. PRODUCTION OF MANNITOL BY LACTIC ACID BACTERIA: A REVIEW

    Mannitol, a naturally occurring polyol, can be produced by lactic acid bacteria (LAB) by fermentation. Some homofermentative LAB produce small amounts of mannitol from glucose. Several heterofermentative LAB can produce mannitol effectively from fructose. In this article, a review on mannitol pro...

  3. Identification and characterisation of probiotic lactic acid bacteria

    Španová, A.; Rittich, B.; Horák, Daniel; Dráb, V.; Drbohlav, J.

    Hydebarad : Osmania University, 2008. s. 17. [International Congress on Bioprocesses in Food Industries /3./ & Convention of the Biotech Research Society India /5./. 06.11.2008-08.11.2008, Hyderabad] Institutional research plan: CEZ:AV0Z40500505 Keywords : probiotic lactic acid bacteria Subject RIV: CE - Biochemistry

  4. Acetic acid bacteria spoilage of bottled red wine -- a review.

    Bartowsky, Eveline J; Henschke, Paul A

    2008-06-30

    Acetic acid bacteria (AAB) are ubiquitous organisms that are well adapted to sugar and ethanol rich environments. This family of Gram-positive bacteria are well known for their ability to produce acetic acid, the main constituent in vinegar. The oxidation of ethanol through acetaldehyde to acetic acid is well understood and characterised. AAB form part of the complex natural microbial flora of grapes and wine, however their presence is less desirable than the lactic acid bacteria and yeast. Even though AAB were described by Pasteur in the 1850s, wine associated AAB are still difficult to cultivate on artificial laboratory media and until more recently, their taxonomy has not been well characterised. Wine is at most risk of spoilage during production and the presence of these strictly aerobic bacteria in grape must and during wine maturation can be controlled by eliminating, or at least limiting oxygen, an essential growth factor. However, a new risk, spoilage of wine by AAB after packaging, has only recently been reported. As wine is not always sterile filtered prior to bottling, especially red wine, it often has a small resident bacterial population (Bottled red wines, sealed with natural cork closures, and stored in a vertical upright position may develop spoilage by acetic acid bacteria. This spoilage is evident as a distinct deposit of bacterial biofilm in the neck of the bottle at the interface of the wine and the headspace of air, and is accompanied with vinegar, sherry, bruised apple, nutty, and solvent like off-aromas, depending on the degree of spoilage. This review focuses on the wine associated AAB species, the aroma and flavour changes in wine due to AAB metabolism, discusses the importance of oxygen ingress into the bottle and presents a hypothesis for the mechanism of spoilage of bottled red wine. PMID:18237809

  5. Lactic acid bacteria isolated from soy sauce mash in Thailand.

    Tanasupawat, Somboon; Thongsanit, Jaruwan; Okada, Sanae; Komagata, Kazuo

    2002-08-01

    Fourteen sphere-shaped and 30 rod-shaped lactic acid bacteria were isolated from soy sauce mash of two factories in Thailand. These strains were separated into two groups, Group A and Group B, by cell shape and DNA-DNA similarity. Group A contained 14 tetrad-forming strains, and these strains were identified as Tetragenococcus halophilus by DNA similarity. Group B contained 30 rod-shaped bacteria, and they were further divided into four Subgroups, B1, B2, B3, and B4, and three ungrouped strains by phenotypic characteristics and DNA similarity. Subgroup B1 contained 16 strains, and these strains were identified as Lactobacillus acidipiscis by DNA similarity. Subgroup B2 included two strains, and the strains were identified as Lactobacillus farciminis by DNA similarity. Subgroup B3 contained five strains. The strains had meso-diaminopimelic acid in the cell wall, and were identified as Lactobacillus pentosus by DNA similarity. The strains tested produced DL-lactic acid from D-glucose. Subgroup B4 contained four strains. The strains had meso-diaminopimelic acid in the cell wall, and they were identified as Lactobacillus plantarum by DNA similarity. Two ungrouped strains were homofermentative, and one was heterofermentative. They showed a low degree of DNA similarity with the type strains tested, and were left unnamed. The distribution of lactic acid bacteria in soy sauce mash in Thailand is discussed. PMID:12469319

  6. Lactic Acid Bacteria – Friend or Foe? Lactic Acid Bacteria in the Production of Polysaccharides and Fuel Ethanol

    Lactic acid bacteria (LAB) have been widely used in the production of fermented foods and as probiotics. Alternan is a glucan with a distinctive backbone structure of alternating a-(1,6) and a-(1,3) linkages produced by the LAB Leuconostoc mesenteroides. In recent years, we have developed improved...

  7. Antibiotic resistance in food lactic acid bacteria--a review.

    Mathur, Shalini; Singh, Rameshwar

    2005-12-15

    Antibiotics are a major tool utilized by the health care industry to fight bacterial infections; however, bacteria are highly adaptable creatures and are capable of developing resistance to antibiotics. Consequently, decades of antibiotic use, or rather misuse, have resulted in bacterial resistance to many modern antibiotics. This antibiotic resistance can cause significant danger and suffering for many people with common bacterial infections, those once easily treated with antibiotics. For several decades studies on selection and dissemination of antibiotic resistance have focused mainly on clinically relevant species. However, recently many investigators have speculated that commensal bacteria including lactic acid bacteria (LAB) may act as reservoirs of antibiotic resistance genes similar to those found in human pathogens. The main threat associated with these bacteria is that they can transfer resistance genes to pathogenic bacteria. Genes conferring resistance to tetracycline, erythromycin and vancomycin have been detected and characterized in Lactococcus lactis, Enterococci and, recently, in Lactobacillus species isolated from fermented meat and milk products. A number of initiatives have been recently launched by various organizations across the globe to address the biosafety concerns of starter cultures and probiotic microorganisms. The studies can lead to better understanding of the role played by the dairy starter microorganisms in horizontal transfer of antibiotic resistance genes to intestinal microorganisms and food-associated pathogenic bacteria. PMID:16289406

  8. Lactic acid bacteria as a cell factory for riboflavin production.

    Thakur, Kiran; Tomar, Sudhir Kumar; De, Sachinandan

    2016-07-01

    Consumers are increasingly becoming aware of their health and nutritional requirements, and in this context, vitamins produced in situ by microbes may suit their needs and expectations. B groups vitamins are essential components of cellular metabolism and among them riboflavin is one of the vital vitamins required by bacteria, plants, animals and humans. Here, we focus on the importance of microbial production of riboflavin over chemical synthesis. In addition, genetic abilities for riboflavin biosynthesis by lactic acid bacteria are discussed. Genetically modified strains by employing genetic engineering and chemical analogues have been developed to enhance riboflavin production. The present review attempts to collect the currently available information on riboflavin production by microbes in general, while placing greater emphasis on food grade lactic acid bacteria and human gut commensals. For designing riboflavin-enriched functional foods, proper selection and exploitation of riboflavin-producing lactic acid bacteria is essential. Moreover, eliminating the in situ vitamin fortification step will decrease the cost of food production. PMID:26686515

  9. Fatty Acid Biosynthesis Revisited: Structure Elucidation and Metabolic Engineering

    Beld, Joris; Lee, D. John; Burkart, Michael D.

    2014-01-01

    Fatty acids are primary metabolites synthesized by complex, elegant, and essential biosynthetic machinery. Fatty acid synthases resemble an iterative assembly line, with an acyl carrier protein conveying the growing fatty acid to necessary enzymatic domains for modification. Each catalytic domain is a unique enzyme spanning a wide range of folds and structures. Although they harbor the same enzymatic activities, two different types of fatty acid synthase architectures are observed in nature. ...

  10. Occurrence and role of lactic acid bacteria in seafood products

    Leroi, Francoise

    2010-01-01

    Lactic acid bacteria (LAB) in fish flesh has long been disregarded because the high post-mortem pH, the low percentage of sugars, the high content of low molecular weight nitrogenous molecules and the low temperature of temperate waters favor the rapid growth of pH-sensitive psychrotolerant marine Gram-negative bacteria like Pseudomonas, Shewanella and Photobacterium. In seafood packed in both vacuum (VP) and modified atmosphere (MAP) packaging commonly CO2 enriched, the growth of the Gram-ne...

  11. Adaptation and tolerance of bacteria against acetic acid.

    Trček, Janja; Mira, Nuno Pereira; Jarboe, Laura R

    2015-08-01

    Acetic acid is a weak organic acid exerting a toxic effect to most microorganisms at concentrations as low as 0.5 wt%. This toxic effect results mostly from acetic acid dissociation inside microbial cells, causing a decrease of intracellular pH and metabolic disturbance by the anion, among other deleterious effects. These microbial inhibition mechanisms enable acetic acid to be used as a preservative, although its usefulness is limited by the emergence of highly tolerant spoilage strains. Several biotechnological processes are also inhibited by the accumulation of acetic acid in the growth medium including production of bioethanol from lignocellulosics, wine making, and microbe-based production of acetic acid itself. To design better preservation strategies based on acetic acid and to improve the robustness of industrial biotechnological processes limited by this acid's toxicity, it is essential to deepen the understanding of the underlying toxicity mechanisms. In this sense, adaptive responses that improve tolerance to acetic acid have been well studied in Escherichia coli and Saccharomyces cerevisiae. Strains highly tolerant to acetic acid, either isolated from natural environments or specifically engineered for this effect, represent a unique reservoir of information that could increase our understanding of acetic acid tolerance and contribute to the design of additional tolerance mechanisms. In this article, the mechanisms underlying the acetic acid tolerance exhibited by several bacterial strains are reviewed, with emphasis on the knowledge gathered in acetic acid bacteria and E. coli. A comparison of how these bacterial adaptive responses to acetic acid stress fit to those described in the yeast Saccharomyces cerevisiae is also performed. A systematic comparison of the similarities and dissimilarities of the ways by which different microbial systems surpass the deleterious effects of acetic acid toxicity has not been performed so far, although such exchange

  12. Cell wall structure and function in lactic acid bacteria.

    Chapot-Chartier, Marie-Pierre; Kulakauskas, Saulius

    2014-08-29

    The cell wall of Gram-positive bacteria is a complex assemblage of glycopolymers and proteins. It consists of a thick peptidoglycan sacculus that surrounds the cytoplasmic membrane and that is decorated with teichoic acids, polysaccharides, and proteins. It plays a major role in bacterial physiology since it maintains cell shape and integrity during growth and division; in addition, it acts as the interface between the bacterium and its environment. Lactic acid bacteria (LAB) are traditionally and widely used to ferment food, and they are also the subject of more and more research because of their potential health-related benefits. It is now recognized that understanding the composition, structure, and properties of LAB cell walls is a crucial part of developing technological and health applications using these bacteria. In this review, we examine the different components of the Gram-positive cell wall: peptidoglycan, teichoic acids, polysaccharides, and proteins. We present recent findings regarding the structure and function of these complex compounds, results that have emerged thanks to the tandem development of structural analysis and whole genome sequencing. Although general structures and biosynthesis pathways are conserved among Gram-positive bacteria, studies have revealed that LAB cell walls demonstrate unique properties; these studies have yielded some notable, fundamental, and novel findings. Given the potential of this research to contribute to future applied strategies, in our discussion of the role played by cell wall components in LAB physiology, we pay special attention to the mechanisms controlling bacterial autolysis, bacterial sensitivity to bacteriophages and the mechanisms underlying interactions between probiotic bacteria and their hosts. PMID:25186919

  13. Phenolic Biotransformations during Conversion of Ferulic Acid to Vanillin by Lactic Acid Bacteria

    Baljinder Kaur

    2013-01-01

    Full Text Available Vanillin is widely used as food additive and as a masking agent in various pharmaceutical formulations. Ferulic acid is an important precursor of vanillin that is available in abundance in cell walls of cereals like wheat, corn, and rice. Phenolic biotransformations can occur during growth of lactic acid bacteria (LAB, and their production can be made feasible using specialized LAB strains that have been reported to produce ferulic acid esterases. The present study aimed at screening a panel of LAB isolates for their ability to release phenolics from agrowaste materials like rice bran and their biotransformation to industrially important compounds such as ferulic acid, 4-ethyl phenol, vanillic acid, vanillin, and vanillyl alcohol. Bacterial isolates were evaluated using ferulic acid esterase, ferulic acid decarboxylase, and vanillin dehydrogenase assays. This work highlights the importance of lactic acid bacteria in phenolic biotransformations for the development of food grade flavours and additives.

  14. Lactobionic and cellobionic acid production profiles of the resting cells of acetic acid bacteria.

    Kiryu, Takaaki; Kiso, Taro; Nakano, Hirofumi; Murakami, Hiromi

    2015-01-01

    Lactobionic acid was produced by acetic acid bacteria to oxidize lactose. Gluconobacter spp. and Gluconacetobacter spp. showed higher lactose-oxidizing activities than Acetobacter spp. Gluconobacter frateurii NBRC3285 produced the highest amount of lactobionic acid per cell, among the strains tested. This bacterium assimilated neither lactose nor lactobionic acid. At high lactose concentration (30%), resting cells of the bacterium showed sufficient oxidizing activity for efficient production of lactobionic acid. These properties may contribute to industrial production of lactobionic acid by the bacterium. The bacterium showed higher oxidizing activity on cellobiose than that on lactose and produced cellobionic acid. PMID:25965080

  15. Lactic acid bacteria fermentations in oat-based suspensions

    Mårtensson, Olof

    2002-01-01

    This thesis deals with the fermentation characteristics of lactic acid bacteria (LAB) in oat-based suspensions, with formulation work of fermented products based on oat and with nutritional studies of these products. Changes in structure in terms of viscosity and ropiness were studied when exopolysaccharide (EPS)-producing LAB strains, namely, Lactobacillus delbrueckii subsp. bulgaricus NCFB 2772, Lactobacillus brevis G-77 and Pediococcus damnosus 2.6 were grown in these oat-based suspensions...

  16. Lactic acid bacteria: the bugs of the new millennium

    Konings, W N; Kok, J; Kuipers, O P; Poolman, B.

    2000-01-01

    Lactic acid bacteria (LABs) are widely used in the manufacturing of fermented food and are among the best-studied microorganisms. Detailed knowledge of a number of physiological traits has opened new potential applications for these organisms in the food industry, while other traits might be beneficial for human health. Important new developments have been made in the research of LABs in the areas of multidrug resistance, bacteriocins and quorum sensing, osmoregulation, proteolysis, autolysin...

  17. Interactions between Cooccurring Lactic Acid Bacteria in Honey Bee Hives

    Rokop, Z. P.; Horton, M. A.; Newton, I. L. G.

    2015-01-01

    In contrast to the honey bee gut, which is colonized by a few characteristic bacterial clades, the hive of the honey bee is home to a diverse array of microbes, including many lactic acid bacteria (LAB). In this study, we used culture, combined with sequencing, to sample the LAB communities found across hive environments. Specifically, we sought to use network analysis to identify microbial hubs sharing nearly identical operational taxonomic units, evidence which may indicate cooccurrence of ...

  18. Naturally Occurring Lactic Acid Bacteria Isolated from Tomato Pomace Silage

    Wu, Jing-Jing; Du, Rui-ping; Gao, Min; Sui, Yao-qiang; Xiu, Lei; Wang, Xiao

    2014-01-01

    Silage making has become a significant method of forage conservation worldwide. To determine how tomato pomace (TP) may be used effectively as animal feed, it was ensilaged for 90 days and microbiology counts, fermentation characteristics and chemical composition of tomato pomace silage (TPS) were evaluated at the 30th, 60th, and 90th days, respectively. In addition, 103 lactic acid bacteria were isolated from TPS. Based on the phenotypic and chemotaxonomic characteristics, 16S rDNA sequence ...

  19. Research of Sichuan Paocai and Lactic Acid Bacteria

    Chen Gong; Yu Wen-Hua; Zhang Qi-sheng; Song Ping; Zhang Bei-Bei; Liu Zhu; You Jing-gang; Li Heng

    2014-01-01

    Sichuan Paocai with long history is a typical representative of Chinese pickles, which has been inherited for thousands years. Its strong vitality was largely due to its unique microbial fermentation style. In this study, molecular microbial technology and traditional microbial technology were employed to study the distributions and changes of the microorganisms during the fermentation. The results showed that the lactic acid bacteria such as Leuconostoc mesenteroides, Lactobacillus plantarum...

  20. SCREENING OF BACTERIA FOR LACTIC ACID PRODUCTION FROM WHEY WATER

    Vethakanraj Helen Shiphrah

    2013-01-01

    Full Text Available Lactobacilli have the property of converting lactose and other sugars to lactic acid through fermentation. So whey water, the greenish translucent liquid rich in lactose, vitamins, proteins and mineral salts, obtained as a by-product after the precipitation of cheese can be used as a substrate for Lactobacilli for lactic acid production which otherwise is a serious environmental pollutant when disposed without pre-treatment. 16 isolates of Lactic acid producing bacteria isolated from various biological sources were inoculated in whey water (1% inoculum and kept at 37°C in the shaker at a speed of 150 revolutions per minute for 36 h. Lactic acid production was estimated after 36 h and the strains 4a, 12a and 15b showed lactic acid production of which 12a produced the highest concentration. The amount of Lactic acid produced by 12a was 0.62 g L-1 under unadjusted condition which is comparable to previously reported strains in enriched medium. So the lactic acid production by strain 12a was further investigated to find the effect of pH and temperature on the production efficiency. Lactic acid production was also checked in Luria-Bertani broth and whey water was found to be the medium of choice for prolonged lactic acid production.

  1. Intracellular pH of acid-tolerant ruminal bacteria.

    Russell, J B

    1991-01-01

    Acid-tolerant ruminal bacteria (Bacteroides ruminicola B1(4), Selenomonas ruminantium HD4, Streptococcus bovis JB1, Megasphaera elsdenii B159, and strain F) allowed their intracellular pH to decline as a function of extracellular pH and did not generate a large pH gradient across the cell membrane until the extracellular pH was low (less than 5.2). This decline in intracellular pH prevented an accumulation of volatile fatty acid anions inside the cells.

  2. Probiotication of tomato juice by lactic acid bacteria.

    Yoon, Kyung Young; Woodams, Edward E; Hang, Yong D

    2004-12-01

    This study was undertaken to determine the suitability of tomato juice as a raw material for production of probiotic juice by four lactic acid bacteria (Latobacillus acidophilus LA39, Lactobacillus plantarum C3, Lactobacillus casei A4, and Lactobacillus delbrueckii D7). Tomato juice was inoculated with a 24-h-old culture and incubated at 30 degrees C. Changes in pH, acidity, sugar content, and viable cell counts during fermentation under controlled conditions were measured. The lactic acid cultures reduced the pH to 4.1 or below and increased the acidity to 0.65% or higher, and the viable cell counts (CFU) reached nearly 1.0 to 9.0 x 10(9)/ml after 72 h fermentation. The viable cell counts of the four lactic acid bacteria in the fermented tomato juice ranged from 10(6) to 10(8) CFU/ml after 4 weeks of cold storage at 4 degrees C. Probiotic tomato juice could serve as a health beverage for vegetarians or consumers who are allergic to dairy products. PMID:15650688

  3. Revisiting the cape cod bacteria injection experiment using a stochastic modeling approach

    Maxwell, R.M.; Welty, C.; Harvey, R.W.

    2007-01-01

    Bromide and resting-cell bacteria tracer tests conducted in a sandy aquifer at the U.S. Geological Survey Cape Cod site in 1987 were reinterpreted using a three-dimensional stochastic approach. Bacteria transport was coupled to colloid filtration theory through functional dependence of local-scale colloid transport parameters upon hydraulic conductivity and seepage velocity in a stochastic advection - dispersion/attachment - detachment model. Geostatistical information on the hydraulic conductivity (K) field that was unavailable at the time of the original test was utilized as input. Using geostatistical parameters, a groundwater flow and particle-tracking model of conservative solute transport was calibrated to the bromide-tracer breakthrough data. An optimization routine was employed over 100 realizations to adjust the mean and variance ofthe natural-logarithm of hydraulic conductivity (InK) field to achieve best fit of a simulated, average bromide breakthrough curve. A stochastic particle-tracking model for the bacteria was run without adjustments to the local-scale colloid transport parameters. Good predictions of mean bacteria breakthrough were achieved using several approaches for modeling components of the system. Simulations incorporating the recent Tufenkji and Elimelech (Environ. Sci. Technol. 2004, 38, 529-536) correlation equation for estimating single collector efficiency were compared to those using the older Rajagopalan and Tien (AIChE J. 1976, 22, 523-533) model. Both appeared to work equally well at predicting mean bacteria breakthrough using a constant mean bacteria diameter for this set of field conditions. Simulations using a distribution of bacterial cell diameters available from original field notes yielded a slight improvement in the model and data agreement compared to simulations using an average bacterial diameter. The stochastic approach based on estimates of local-scale parameters for the bacteria-transport process reasonably captured

  4. Lactic acid bacteria from fresh fruit and vegetables as biocontrol agents of phytopathogenic bacteria and fungi.

    Trias, Rosalia; Bañeras, Lluís; Montesinos, Emilio; Badosa, Esther

    2008-12-01

    This study evaluated the efficacy of lactic acid bacteria (LAB) isolated from fresh fruits and vegetables as biocontrol agents against the phytopathogenic and spoilage bacteria and fungi, Xanthomonas campestris, Erwinia carotovora, Penicillium expansum, Monilinia laxa, and Botrytis cinerea. The antagonistic activity of 496 LAB strains was tested in vitro and all tested microorganisms except P. expansum were inhibited by at least one isolate. The 496 isolates were also analyzed for the inhibition of P. expansum infection in wounds of Golden Delicious apples. Four strains (TC97, AC318, TM319, and FF441) reduced the fungal rot diameter of the apples by 20%; only Weissella cibaria strain TM128 decreased infection levels by 50%. Cell-free supernatants of selected antagonistic bacteria were studied to determine the nature of the antimicrobial compounds produced. Organic acids were the preferred mediators of inhibition but hydrogen peroxide was also detected when strains BC48, TM128, PM141 and FF441 were tested against E. carotovora. While previous reports of antifungal activity by LAB are scarce, our results support the potential of LAB as biocontrol agents against postharvest rot. PMID:19204894

  5. Mechanistic modeling of biocorrosion caused by biofilms of sulfate reducing bacteria and acid producing bacteria.

    Xu, Dake; Li, Yingchao; Gu, Tingyue

    2016-08-01

    Biocorrosion is also known as microbiologically influenced corrosion (MIC). Most anaerobic MIC cases can be classified into two major types. Type I MIC involves non-oxygen oxidants such as sulfate and nitrate that require biocatalysis for their reduction in the cytoplasm of microbes such as sulfate reducing bacteria (SRB) and nitrate reducing bacteria (NRB). This means that the extracellular electrons from the oxidation of metal such as iron must be transported across cell walls into the cytoplasm. Type II MIC involves oxidants such as protons that are secreted by microbes such as acid producing bacteria (APB). The biofilms in this case supply the locally high concentrations of oxidants that are corrosive without biocatalysis. This work describes a mechanistic model that is based on the biocatalytic cathodic sulfate reduction (BCSR) theory. The model utilizes charge transfer and mass transfer concepts to describe the SRB biocorrosion process. The model also includes a mechanism to describe APB attack based on the local acidic pH at a pit bottom. A pitting prediction software package has been created based on the mechanisms. It predicts long-term pitting rates and worst-case scenarios after calibration using SRB short-term pit depth data. Various parameters can be investigated through computer simulation. PMID:27071053

  6. Bacteriocins from lactic acid bacteria and their applications in meat and meat products.

    Woraprayote, Weerapong; Malila, Yuwares; Sorapukdee, Supaluk; Swetwiwathana, Adisorn; Benjakul, Soottawat; Visessanguan, Wonnop

    2016-10-01

    Meat and meat products have always been an important part of human diet, and contain valuable nutrients for growth and health. Nevertheless, they are perishable and susceptible to microbial contamination, leading to an increased health risk for consumers as well as to the economic loss in meat industry. The utilization of bacteriocins produced by lactic acid bacteria (LAB) as a natural preservative has received a considerable attention. Inoculation of bacteriocin-producing LAB cell as starter or protective cultures is suitable for fermented meats, whilst the direct addition of bacteriocin as food additive is more preferable when live cells of LAB could not produce bacteriocin in the real meat system. The incorporation of bacteriocins in packaging is another way to improve meat safety to avoid direct addition of bacteriocin to meat. Utilization of bacteriocins can effectively contribute to food safety, especially when integrated into hurdle concepts. In this review, LAB bacteriocins and their applications in meat and meat products are revisited. The molecular structure and characteristics of bacteriocins recently discovered, as well as exemplary properties are also discussed. PMID:27118166

  7. CHARACTERIZATION OF LACTIC ACID BACTERIA ISOLATED FROM SUMBAWA MARE MILK

    Nengah Sujaya

    2008-06-01

    Full Text Available A study was carried out to isolate and characterize lactic acid bacteria (LAB from the Sumbawa mares milk The Isolation of LAB was conducted in Man Rogosa Sharpe (MRS agar. The isolates were characterized by standard methods, such as Gram staining, cell morphology study and fermentation activities. The ability of the isolates to inhibit some pathogenic bacteria was studied by dual culture assay. Isolates showing the widest spectrum of inhibiting pathogenic bacteria were further identified using API 50 CHL. The results showed that Sumbawa mare milk was dominated by lactobacilli and weisella/leuconostoc. As many as 26 out 36 isolates belong to homofermentative lactobacilli and another 10 isolates belong to both heterofermentative lactobacilli and weissella or leuconostoc. Twenty four isolates inhibited the growth of Escherichia coli 25922, Shigela flexneri, Salmonella typhimurium, and Staphylococcus aureus 29213. Two promising isolates with the widest spectrum of inhibiting pathogenic bacteria, Lactobacillus sp. SKG34 and Lactobacillus sp. SKG49, were identified respectively as Lactobacillus rhamnosus SKG34 and Lactobacillus ramnosus SKG49. These two isolates were specific strains of the sumbawa mare milk and are very potential to be developed as probiotic for human.

  8. Inhibition of citrus fungal pathogens by using lactic acid bacteria.

    Gerez, C L; Carbajo, M S; Rollán, G; Torres Leal, G; Font de Valdez, G

    2010-08-01

    The effect of lactic acid bacteria (LAB) on pathogenic fungi was evaluated and the metabolites involved in the antifungal effect were characterized. Penicillium digitatum (INTA 1 to INTA 7) and Geotrichum citri-aurantii (INTA 8) isolated from decayed lemon from commercial packinghouses were treated with imazalil and guazatine to obtain strains resistant to these fungicides. The most resistant strains (4 fungal strains) were selected for evaluating the antifungal activity of 33 LAB strains, among which only 8 strains gave positive results. The antifungal activity of these LAB strains was related to the production of lactic acid, acetic acid, and phenyllactic acid (PLA). A central composite design and the response surface methodology were used to evaluate the inhibitory effect of the organic acids produced by the LAB cultures. The antifungal activity of lactic acid was directly related to its concentration; however, acetic acid and PLA showed a peak of activity at 52.5 and 0.8 mM, respectively, with inhibition rates similar to those obtained with Serenade((R)) (3.0 ppm) imazalil (50 ppm) and guazatine (50 ppm). Beyond the peak of activity, a reduction in effectiveness of both acetic acid and PLA was observed. Comparing the inhibition rate of the organic acids, PLA was about 66- and 600-fold more effective than acetic acid and lactic acid, respectively. This study presents evidences on the antifungal effect of selected LAB strains and their end products. Studies are currently being undertaken to evaluate the effectiveness in preventing postharvest diseases on citrus fruits. PMID:20722936

  9. Revisiting the Cape Cod Bacteria Injection Experiment Using a Stochastic Modeling Approach

    Maxwell, R M; Welty, C; Harvey, R W

    2006-11-22

    Bromide and resting-cell bacteria tracer tests carried out in a sand and gravel aquifer at the USGS Cape Cod site in 1987 were reinterpreted using a three-dimensional stochastic approach and Lagrangian particle tracking numerical methods. Bacteria transport was strongly coupled to colloid filtration through functional dependence of local-scale colloid transport parameters on hydraulic conductivity and seepage velocity in a stochastic advection-dispersion/attachment-detachment model. Information on geostatistical characterization of the hydraulic conductivity (K) field from a nearby plot was utilized as input that was unavailable when the original analysis was carried out. A finite difference model for groundwater flow and a particle-tracking model of conservative solute transport was calibrated to the bromide-tracer breakthrough data using the aforementioned geostatistical parameters. An optimization routine was utilized to adjust the mean and variance of the lnK field over 100 realizations such that a best fit of a simulated, average bromide breakthrough curve is achieved. Once the optimal bromide fit was accomplished (based on adjusting the lnK statistical parameters in unconditional simulations), a stochastic particle-tracking model for the bacteria was run without adjustments to the local-scale colloid transport parameters. Good predictions of the mean bacteria breakthrough data were achieved using several approaches for modeling components of the system. Simulations incorporating the recent Tufenkji and Elimelech [1] equation for estimating single collector efficiency were compared to those using the Rajagopalan and Tien [2] model. Both appeared to work equally well at predicting mean bacteria breakthrough using a constant mean bacteria diameter for this set of field conditions, with the Rajagopalan and Tien model yielding approximately a 30% lower peak concentration and less tailing than the Tufenkji and Elimelech formulation. Simulations using a distribution

  10. Affinity sensor using 3-aminophenylboronic acid for bacteria detection.

    Wannapob, Rodtichoti; Kanatharana, Proespichaya; Limbut, Warakorn; Numnuam, Apon; Asawatreratanakul, Punnee; Thammakhet, Chongdee; Thavarungkul, Panote

    2010-10-15

    Boronic acid that can reversibly bind to diols was used to detect bacteria through its affinity binding reaction with diol-groups on bacterial cell walls. 3-aminophenylboronic acid (3-APBA) was immobilized on a gold electrode via a self-assembled monolayer. The change in capacitance of the sensing surface caused by the binding between 3-APBA and bacteria in a flow system was detected by a potentiostatic step method. Under optimal conditions the linear range of 1.5×10(2)-1.5×10(6) CFU ml(-1) and the detection limit of 1.0×10(2) CFU ml(-1) was obtained. The sensing surface can be regenerated and reused up to 58 times. The method was used for the analysis of bacteria in several types of water, i.e., bottled, well, tap, reservoir and wastewater. Compared with the standard plate count method, the results were within one standard deviation of each other. The proposed method can save both time and cost of analysis. The electrode modified with 3-APBA would also be applicable to the detection of other cis-diol-containing analytes. The concept could be extended to other chemoselective ligands, offering less expensive and more robust affinity sensors for a wide range of compounds. PMID:20801635

  11. Biosynthesis of myristic acid in luminescent bacteria. [Vibrio harveyi

    Byers, D.M.

    1987-05-01

    In vivo pulse-label studies have demonstrated that luminescent bacteria can provide myritic acid (14:0) required for the synthesis of the luciferase substrate myristyl aldehyde. Luminescent wild type Vibrio harveyi incubated with (/sup 14/C) acetate in a nutrient-depleted medium accumulated substantial tree (/sup 14/C)fatty acid (up to 20% of the total lipid label). Radio-gas chromatography revealed that > 75% of the labeled fatty acid is 14:0. No free fatty acid was detected in wild type cells labeled prior to the development of bioluminescence in the exponential growth phase, or in a dark mutant of V. harveyi (mutant M17) that requires exogenous 14:0 for light emission. The preferential accumulation of 14:0 was not observed when wild type cells were labeled with (/sup 14/C)acetate in regular growth medium. Moreover, all V. harveyi strains exhibited similar fatty acid mass compositions regardless of the state of bioluminescence. Since earlier work has shown that a luminescence-related acyltransferase (defective in the M17 mutant) can catalyze the deacylation of fatty acyl-acyl carrier protein in vitro, the present results are consistent with a model in which this enzyme diverts 14:0 to the luminescence system during fatty acid biosynthesis. Under normal conditions, the supply of 14:0 by this pathway is tightly regulated such that bioluminescence development does not significantly alter the total fatty acid composition.

  12. Ability of Thermophilic Lactic Acid Bacteria To Produce Aroma Compounds from Amino Acids

    Helinck, Sandra; Le Bars, Dominique; Moreau, Daniel; Yvon, Mireille

    2004-01-01

    Although a large number of key odorants of Swiss-type cheese result from amino acid catabolism, the amino acid catabolic pathways in the bacteria present in these cheeses are not well known. In this study, we compared the in vitro abilities of Lactobacillus delbrueckii subsp. lactis, Lactobacillus helveticus, and Streptococcus thermophilus to produce aroma compounds from three amino acids, leucine, phenylalanine, and methionine, under mid-pH conditions of cheese ripening (pH 5.5), and we investigated the catabolic pathways used by these bacteria. In the three lactic acid bacterial species, amino acid catabolism was initiated by a transamination step, which requires the presence of an α-keto acid such as α-ketoglutarate (α-KG) as the amino group acceptor, and produced α-keto acids. Only S. thermophilus exhibited glutamate dehydrogenase activity, which produces α-KG from glutamate, and consequently only S. thermophilus was capable of catabolizing amino acids in the reaction medium without α-KG addition. In the presence of α-KG, lactobacilli produced much more varied aroma compounds such as acids, aldehydes, and alcohols than S. thermophilus, which mainly produced α-keto acids and a small amount of hydroxy acids and acids. L. helveticus mainly produced acids from phenylalanine and leucine, while L. delbrueckii subsp. lactis produced larger amounts of alcohols and/or aldehydes. Formation of aldehydes, alcohols, and acids from α-keto acids by L. delbrueckii subsp. lactis mainly results from the action of an α-keto acid decarboxylase, which produces aldehydes that are then oxidized or reduced to acids or alcohols. In contrast, the enzyme involved in the α-keto acid conversion to acids in L. helveticus and S. thermophilus is an α-keto acid dehydrogenase that produces acyl coenzymes A. PMID:15240255

  13. Amino acid catabolism and generation of volatiles by lactic acid bacteria

    Tavaria, F. K.; Dahl, S.; Carballo, F. J.; Malcata, F. X.

    2002-01-01

    Twelve isolates of lactic acid bacteria, belonging to the Lactobacillus, Lactococcus, Leuconostoc, and Enterococcus genera, were previously isolated from 180- d-old Serra da Estrela cheese, a traditional Portuguese cheese manufactured from raw milk and coagulated with a plant rennet. These isolates were subsequently tested for their ability to catabolize free amino acids, when incubated independently with each amino acid in free form or with a mixture thereof. Attempts...

  14. Phenolic Biotransformations during Conversion of Ferulic Acid to Vanillin by Lactic Acid Bacteria

    Baljinder Kaur; Debkumar Chakraborty; Balvir Kumar

    2013-01-01

    Vanillin is widely used as food additive and as a masking agent in various pharmaceutical formulations. Ferulic acid is an important precursor of vanillin that is available in abundance in cell walls of cereals like wheat, corn, and rice. Phenolic biotransformations can occur during growth of lactic acid bacteria (LAB), and their production can be made feasible using specialized LAB strains that have been reported to produce ferulic acid esterases. The present study aimed at screening a panel...

  15. Development of Mucosal Vaccines Based on Lactic Acid Bacteria

    Bermúdez-Humarán, Luis G.; Innocentin, Silvia; Lefèvre, Francois; Chatel, Jean-Marc; Langella, Philippe

    Today, sufficient data are available to support the use of lactic acid bacteria (LAB), notably lactococci and lactobacilli, as delivery vehicles for the development of new mucosal vaccines. These non-pathogenic Gram-positive bacteria have been safely consumed by humans for centuries in fermented foods. They thus constitute an attractive alternative to the attenuated pathogens (most popular live vectors actually studied) which could recover their pathogenic potential and are thus not totally safe for use in humans. This chapter reviews the current research and advances in the use of LAB as live delivery vectors of proteins of interest for the development of new safe mucosal vaccines. The use of LAB as DNA vaccine vehicles to deliver DNA directly to antigen-presenting cells of the immune system is also discussed.

  16. Current taxonomy of phages infecting lactic acid bacteria

    Jennifer eMahony

    2014-01-01

    Full Text Available Phages infecting lactic acid bacteria have been the focus of significant research attention over the past three decades. Through the isolation and characterization of hundreds of phage isolates, it has been possible to classify phages of the dairy starter and adjunct bacteria Lactococus lactis, Streptococcus thermophilus, Leuconostoc spp. and Lactobacillus spp. Among these, phages of L. lactis have been most thoroughly scrutinized and serve as an excellent model system to address issues that arise when attempting taxonomic classification of phages infecting other LAB species. Here, we present an overview of the current taxonomy of phages infecting LAB genera of industrial significance, the methods employed in these taxonomic efforts and how these may be employed for the taxonomy of phages of currently underrepresented and emerging phage species.

  17. Screening and characterization of novel bacteriocins from lactic acid bacteria.

    Zendo, Takeshi

    2013-01-01

    Bacteriocins produced by lactic acid bacteria (LAB) are expected to be safe antimicrobial agents. While the best studied LAB bacteriocin, nisin A, is widely utilized as a food preservative, various novel ones are required to control undesirable bacteria more effectively. To discover novel bacteriocins at the early step of the screening process, we developed a rapid screening system that evaluates bacteriocins produced by newly isolated LAB based on their antibacterial spectra and molecular masses. By means of this system, various novel bacteriocins were identified, including a nisin variant, nisin Q, a two-peptide bacteriocin, lactococcin Q, a leaderless bacteriocin, lacticin Q, and a circular bacteriocin, lactocyclicin Q. Moreover, some LAB isolates were found to produce multiple bacteriocins. They were characterized as to their structures, mechanisms of action, and biosynthetic mechanisms. Novel LAB bacteriocins and their biosynthetic mechanisms are expected for applications such as food preservation and peptide engineering. PMID:23649268

  18. Metabolic strategies of beer spoilage lactic acid bacteria in beer.

    Geissler, Andreas J; Behr, Jürgen; von Kamp, Kristina; Vogel, Rudi F

    2016-01-01

    Beer contains only limited amounts of readily fermentable carbohydrates and amino acids. Beer spoilage lactic acid bacteria (LAB) have to come up with metabolic strategies in order to deal with selective nutrient content, high energy demand of hop tolerance mechanisms and a low pH. The metabolism of 26 LAB strains of 6 species and varying spoilage potentialwas investigated in order to define and compare their metabolic capabilities using multivariate statistics and outline possible metabolic strategies. Metabolic capabilities of beer spoilage LAB regarding carbohydrate and amino acids did not correlate with spoilage potential, but with fermentation type (heterofermentative/homofermentative) and species. A shift to mixed acid fermentation by homofermentative (hof) Pediococcus claussenii and Lactobacillus backii was observed as a specific feature of their growth in beer. For heterofermentative (hef) LAB a mostly versatile carbohydrate metabolism could be demonstrated, supplementing the known relevance of organic acids for their growth in beer. For hef LAB a distinct amino acid metabolism, resulting in biogenic amine production, was observed, presumably contributing to energy supply and pH homeostasis. PMID:26398285

  19. Fermentation of aqueous plant seed extracts by lactic acid bacteria

    Schafner, D.W.; Beuchat, R.L.

    1986-05-01

    The effects of lactic acid bacterial fermentation on chemical and physical changes in aqueous extracts of cowpea (Vigna unguiculata), peanut (Arachis hypogea), soybean (Glycine max), and sorghum (Sorghum vulgare) were studied. The bacteria investigated were Lactobacillus helveticus, L. delbrueckii, L. casei, L. bulgaricus, L. acidophilus, and Streptococcus thermophilus. Organisms were inoculated individually into all of the seed extracts; L. bulgaricus and S. thermophilus were also evaluated together as inocula for fermenting the legume extracts. During fermentation, bacterial population and changes in titratable acidity, pH, viscosity, and color were measured over a 72 h period at 37 degrees C. Maximum bacterial populations, titratable acidity, pH, and viscosity varied depending upon the type of extract and bacterial strain. The maximum population of each organism was influenced by fermentable carbohydrates, which, in turn, influenced acid production and change in pH. Change in viscosity was correlated with the amount of protein and titratable acidity of products. Color was affected by pasteurization treatment and fermentation as well as the source of extract. In the extracts inoculated simultaneously with L. bulgaricus and S. thermophilus, a synergistic effect resulted in increased bacterial populations, titratable acidity, and viscosity, and decreased pH in all the legume extracts when compared to the extracts fermented with either of these organisms individually. Fermented extracts offer potential as substitutes for cultured dairy products. 24 references.

  20. Occurrence and role of lactic acid bacteria in seafood products.

    Françoise, Leroi

    2010-09-01

    Lactic acid bacteria (LAB) in fish flesh has long been disregarded because the high post-mortem pH, the low percentage of sugars, the high content of low molecular weight nitrogenous molecules and the low temperature of temperate waters favor the rapid growth of pH-sensitive psychrotolerant marine Gram-negative bacteria like Pseudomonas, Shewanella and Photobacterium. In seafood packed in both vacuum (VP) and modified atmosphere (MAP) packaging commonly CO(2) enriched, the growth of the Gram-negative aerobic bacteria group (predominantly pseudomonads) is effectively inhibited and the number reached by LAB during storage is higher than that achieved in air but always several log units lower than the trimethylamine oxide (TMA-O) reducing and CO(2)-resistant organisms (Shewanella putrefaciens and Photobacterium phosphoreum). Accordingly, LAB are not of much concern in seafood neither aerobically stored nor VP and MAP. However, they may acquire great relevance in lightly preserved fish products (LPFP), including those VP or MAP. Fresh fish presents a very high water activity (aw) value (0.99). However, aw is reduced to about 0.96 when salt (typically 6% WP) is added to the product. As a result, aerobic Gram-negative bacteria are inhibited, which allows the growth of other organisms more resistant to reduced aw, i.e. LAB, and then they may acquire a central role in the microbial events occurring in the product. Changes in consumers' habits have led to an increase of convenient LPFP with a relative long shelf-life (at least 3 weeks) which, on the other hand, may constitute a serious problem from a safety perspective since Listeria monocytogenes and sometimes Clostridium botulinum (mainly type E) may able to grow. In any case the LAB function in marine products is complex, depending on species, strains, interaction with other bacteria and the food matrix. They may have no particular effect or they may be responsible for spoilage and, in certain cases, they may even exert

  1. Preparation of lactic acid bacteria fermented wheat-yoghurt mixtures

    Michal Magala

    2013-09-01

    Full Text Available Background. Tarhana, a wheat-yoghurt fermented mixture, is considered as a good source of saccharides, proteins, some vitamins and minerals. Moreover, their preparation is inexpensive and lactic acid fermentation offers benefi ts like product preservation, enhancement of nutritive value and sensory properties improvement. The aim of this work was to evaluate changes of some chemical parameters during fermentation of tarhana, when the level of salt and amount of yoghurt used were varied. Some functional and sensory characteristics of the fi nal product were also determined. Material and methods. Chemical analysis included determination of pH, titrable acidity, content of reducing saccharides, lactic, acetic and citric acid. Measured functional properties of tarhana powder were foaming capacity, foam stability, water absorption capacity, oil absorption capacity and emulsifying activity. Tarhana soups samples were evaluated for their sensory characteristics (colour, odor, taste, consistency and overall acceptability. Results. Fermentation of tarhana by lactic acid bacteria and yeasts led to decrease in pH, content of reducing saccharides and citric acid, while titrable acidity and concentration of lactic and acetic acid increased. Determination of functional properties of tarhana powder showed, that salt absence and increased amount of yoghurt in tarhana recipe reduced foaming capacity and oil absorption capacity, whereas foam stability and water absorption capacity were improved. Sensory evaluation of tarhana soups showed that variations in tarhana recipe adversly affected sensory parameters of fi nal products. Conclusion. Variations in tarhana recipe (salt absence, increased proportion of yoghurt led to changes in some chemical parameters (pH, titrable acidity, reducing saccharides, content of lactic, acetic and citric acid. Functional properties were also affected with changed tarhana recipe. Sensory characteristics determination showed, that

  2. Phytase-active lactic acid bacteria from sourdoughs

    Nuobariene, Lina; Cizeikiene, Dalia; Gradzeviciute, Egle;

    2015-01-01

    Whole-grain foods play an important role in human diet as they are relatively rich in minerals, however, the absorption of those minerals in human gut can be very low due to high content of the mineral binding phytate. Therefore, the object of this study was to identify phytase-active lactic acid...... bacteria (LAB) which could be used as a starter to increase mineral bioavailability in whole-meal bread. Hence, LAB isolates were isolated from Lithuanian sourdoughs, tested for phytase activity, and phytase active isolates were identified. Studies of phytase activity of the isolates were carried out at...

  3. Overview on mechanisms of acetic acid resistance in acetic acid bacteria.

    Wang, Bin; Shao, Yanchun; Chen, Fusheng

    2015-02-01

    Acetic acid bacteria (AAB) are a group of gram-negative or gram-variable bacteria which possess an obligate aerobic property with oxygen as the terminal electron acceptor, meanwhile transform ethanol and sugar to corresponding aldehydes, ketones and organic acids. Since the first genus Acetobacter of AAB was established in 1898, 16 AAB genera have been recorded so far. As the main producer of a world-wide condiment, vinegar, AAB have evolved an elegant adaptive system that enables them to survive and produce a high concentration of acetic acid. Some researches and reviews focused on mechanisms of acid resistance in enteric bacteria and made the mechanisms thoroughly understood, while a few investigations did in AAB. As the related technologies with proteome, transcriptome and genome were rapidly developed and applied to AAB research, some plausible mechanisms conferring acetic acid resistance in some AAB strains have been published. In this review, the related mechanisms of AAB against acetic acid with acetic acid assimilation, transportation systems, cell morphology and membrane compositions, adaptation response, and fermentation conditions will be described. Finally, a framework for future research for anti-acid AAB will be provided. PMID:25575804

  4. Diversity of lactic acid bacteria of the bioethanol process

    Azevedo Vasco

    2010-11-01

    Full Text Available Abstract Background Bacteria may compete with yeast for nutrients during bioethanol production process, potentially causing economic losses. This is the first study aiming at the quantification and identification of Lactic Acid Bacteria (LAB present in the bioethanol industrial processes in different distilleries of Brazil. Results A total of 489 LAB isolates were obtained from four distilleries in 2007 and 2008. The abundance of LAB in the fermentation tanks varied between 6.0 × 105 and 8.9 × 108 CFUs/mL. Crude sugar cane juice contained 7.4 × 107 to 6.0 × 108 LAB CFUs. Most of the LAB isolates belonged to the genus Lactobacillus according to rRNA operon enzyme restriction profiles. A variety of Lactobacillus species occurred throughout the bioethanol process, but the most frequently found species towards the end of the harvest season were L. fermentum and L. vini. The different rep-PCR patterns indicate the co-occurrence of distinct populations of the species L. fermentum and L. vini, suggesting a great intraspecific diversity. Representative isolates of both species had the ability to grow in medium containing up to 10% ethanol, suggesting selection of ethanol tolerant bacteria throughout the process. Conclusions This study served as a first survey of the LAB diversity in the bioethanol process in Brazil. The abundance and diversity of LAB suggest that they have a significant impact in the bioethanol process.

  5. Production of probiotic cabbage juice by lactic acid bacteria.

    Yoon, Kyung Young; Woodams, Edward E; Hang, Yong D

    2006-08-01

    Research was undertaken to determine the suitability of cabbage as a raw material for production of probiotic cabbage juice by lactic acid bacteria (Lactobacillus plantarum C3, Lactobacillus casei A4, and Lactobacillus delbrueckii D7). Cabbage juice was inoculated with a 24-h-old lactic culture and incubated at 30 degrees C. Changes in pH, acidity, sugar content, and viable cell counts during fermentation under controlled conditions were monitored. L. casei, L. delbrueckii, and L. plantarum grew well on cabbage juice and reached nearly 10x10(8) CFU/mL after 48 h of fermentation at 30 degrees C. L. casei, however, produced a smaller amount of titratable acidity expressed as lactic acid than L. delbrueckii or L. plantarum. After 4 weeks of cold storage at 4 degrees C, the viable cell counts of L. plantarum and L. delbrueckii were still 4.1x10(7) and 4.5x10(5) mL(-1), respectively. L. casei did not survive the low pH and high acidity conditions in fermented cabbage juice and lost cell viability completely after 2 weeks of cold storage at 4 degrees C. Fermented cabbage juice could serve as a healthy beverage for vegetarians and lactose-allergic consumers. PMID:16125381

  6. Antagonism Between Osmophilic Lactic Acid Bacteria and Yeasts in Brine Fermentation of Soy Sauce

    Noda, Fumio; HAYASHI, Kazuya; Mizunuma, Takeji

    1980-01-01

    Brine fermentation by osmophilic lactic acid bacteria and yeasts for long periods of time is essential to produce a good quality of shoyu (Japanese fermented soy sauce). It is well known that lactic acid fermentation by osmophilic lactic acid bacteria results in the depression of alcoholic fermentation by osmophilic yeasts, but the nature of the interaction between osmophilic lactic acid bacteria and yeasts in brine fermentation of shoyu has not been revealed. The inhibitory effect of osmophi...

  7. Bacteriocins produced by lactic acid bacteria: A review

    Vesković-Moračanin Slavica M.

    2014-01-01

    Full Text Available Lactic acid bacteria (LAB have an essential role in the production of fermented products. With their metabolic activity, they influence the ripening processes - leading to desired sensory qualities while at the same time inhibiting the growth of undesired microorganisms. Because of their dominant role during fermentation and because of a long tradition of utilization, Lhave been designated as “safe microbiota”. Biological protection of LAB, as a naturally present and/or selected and intentionally added microflora, is realized through the production of non-specific (lactic acid, acetic acid and other volatile organic acids, hydrogen peroxide, diacetyl, etc and specific metabolites, bacteriocins. Bacteriocins are extracellularly released proteins or peptides which possess certain antibacterial activity towards certain types of microorganisms, usually related to the producing bacteria. Today, bacteriocins represent a very interesting potential for their application in the food industry. Their application can reduce the use of synthetic preservatives and/or the intensity of thermal treatment during food production consumer’s need for safe, fresh and minimally-processed food. With the intention of realizing this potential to the fullest, it is necessary to understand the nature of bacteriocins, their production mechanisms, regulations and actions, as well as the influence of external factors on the their antimicrobial activity. The composition of food, i.e. its characteristics (pH, temperature, ingredients and additives, types and quantities of epiphytic microbiota and the actual technological process used in production, can all influence the stability and activity of the added bacteriocins. The future research in this field should also aim to clarify this unknown aspect of the application of bacteriocins, to provide the necessary knowledge about the optimization of the external conditions and open up the possibility of discovering their new

  8. Probiotic properties of endemic strains of lactic acid bacteria

    Flora N. Tkhruni

    2013-01-01

    Full Text Available Strains of lactic acid bacteria (LAB isolated from various samples of matsun, yogurt and salted cheese from natural farms of Armenia were studied. They have high antimicrobial and probiotic activities, growth rate and differ by their resistance to enzymes. Supernatants of LAB retain bactericidal activity at рН 3.0-8.0 and inhibit growth of various microflora. The application of different methods of identification and LAB genotyping (API 50 CH, 16S rRNA sequencing, GS-PCR, RAPD PCR showed that isolated LAB evidenced a 99.9% similarity with L. rhamnosus, L. plantarum and L. pentosus species and coccoid forms of Streptococcus and Enterococcus species. It can be concluded, that some strains of lactic acid bacteria, isolated from dairy products from natural farms of Armenia, can be properly used for biopreservation of some foodstuffs. On the basis of experimental data, the LAB can be used as basis for obtaining the new products of functional nutrition.

  9. Naturally occurring lactic Acid bacteria isolated from tomato pomace silage.

    Wu, Jing-Jing; Du, Rui-Ping; Gao, Min; Sui, Yao-Qiang; Xiu, Lei; Wang, Xiao

    2014-05-01

    Silage making has become a significant method of forage conservation worldwide. To determine how tomato pomace (TP) may be used effectively as animal feed, it was ensilaged for 90 days and microbiology counts, fermentation characteristics and chemical composition of tomato pomace silage (TPS) were evaluated at the 30th, 60th, and 90th days, respectively. In addition, 103 lactic acid bacteria were isolated from TPS. Based on the phenotypic and chemotaxonomic characteristics, 16S rDNA sequence and carbohydrate fermentation tests, the isolates were identified as 17 species namely: Lactobacillus coryniformis subsp. torquens (0.97%), Lactobacillus pontis (0.97%), Lactobacillus hilgardii (0.97%), Lactobacillus pantheris (0.97%), Lactobacillus amylovorus (1.9%), Lactobacillus panis (1.9%), Lactobacillus vaginalis (1.9%), Lactobacillus rapi (1.9%), Lactobacillus buchneri (2.9%), Lactobacillus parafarraginis (2.9%), Lactobacillus helveticus (3.9%), Lactobacillus camelliae (3.9%), Lactobacillus fermentum (5.8%), Lactobacillus manihotivorans (6.8%), Lactobacillus plantarum (10.7%), Lactobacillus harbinensis (16.5%) and Lactobacillus paracasei subsp. paracasei (35.0%). This study has shown that TP can be well preserved for 90 days by ensilaging and that TPS is not only rich in essential nutrients, but that physiological and biochemical properties of the isolates could provide a platform for future design of lactic acid bacteria (LAB) inoculants aimed at improving the fermentation quality of silage. PMID:25049999

  10. Naturally Occurring Lactic Acid Bacteria Isolated from Tomato Pomace Silage

    Wu, Jing-jing; Du, Rui-ping; Gao, Min; Sui, Yao-qiang; Xiu, Lei; Wang, Xiao

    2014-01-01

    Silage making has become a significant method of forage conservation worldwide. To determine how tomato pomace (TP) may be used effectively as animal feed, it was ensilaged for 90 days and microbiology counts, fermentation characteristics and chemical composition of tomato pomace silage (TPS) were evaluated at the 30th, 60th, and 90th days, respectively. In addition, 103 lactic acid bacteria were isolated from TPS. Based on the phenotypic and chemotaxonomic characteristics, 16S rDNA sequence and carbohydrate fermentation tests, the isolates were identified as 17 species namely: Lactobacillus coryniformis subsp. torquens (0.97%), Lactobacillus pontis (0.97%), Lactobacillus hilgardii (0.97%), Lactobacillus pantheris (0.97%), Lactobacillus amylovorus (1.9%), Lactobacillus panis (1.9%), Lactobacillus vaginalis (1.9%), Lactobacillus rapi (1.9%), Lactobacillus buchneri (2.9%), Lactobacillus parafarraginis (2.9%), Lactobacillus helveticus (3.9%), Lactobacillus camelliae (3.9%), Lactobacillus fermentum (5.8%), Lactobacillus manihotivorans (6.8%), Lactobacillus plantarum (10.7%), Lactobacillus harbinensis (16.5%) and Lactobacillus paracasei subsp. paracasei (35.0%). This study has shown that TP can be well preserved for 90 days by ensilaging and that TPS is not only rich in essential nutrients, but that physiological and biochemical properties of the isolates could provide a platform for future design of lactic acid bacteria (LAB) inoculants aimed at improving the fermentation quality of silage. PMID:25049999

  11. IN VITRO CHARACTERIZATION OF PROBIOTIC PROPERTIES OF LACTIC ACID BACTERIA FROM BULGARIAN RYE SOURDOUGHS

    Dobreva-Yosifova, G.; Yocheva, L.; Mehmed, A.; Danova, S.; Antonova-Nikolova, S.

    2009-01-01

    Lactic acid bacteria play a key role in human health. These friendly bacteria as a part of the microflora of the gastrointestinal tract (GIT) have a beneficial influence on microbial balance. The probiotic cultures stimulate the growth of beneficial microorganisms, crowd out potentially harmful bacteria and reinforce the body's natural defense mechanisms. Recent data improve the positive effects of probiotics and stimulate research for discovering of new lactic acid bacteria strains with prob...

  12. Protection of live bacteria from bile acid toxicity using bile acid adsorbing resins.

    Edwards, Alexander D; Slater, Nigel K H

    2009-06-12

    We previously demonstrated that a dry, room temperature stable formulation of a live bacterial vaccine was highly susceptible to bile, and suggested that this will lead to significant loss of viability of any live bacterial formulation released into the intestine using an enteric coating or capsule. We found that bile and acid tolerance is very rapidly recovered after rehydration with buffer or water, raising the possibility that rehydration in the absence of bile prior to release into the intestine might solve the problem of bile toxicity to dried cells. We describe here a novel formulation that combines extensively studied bile acid adsorbent resins with the dried bacteria, to temporarily adsorb bile acids and allow rehydration and recovery of bile resistance of bacteria in the intestine before release. Tablets containing the bile acid adsorbent cholestyramine release 250-fold more live bacteria when dissolved in a bile solution, compared to control tablets without cholestyramine or with a control resin that does not bind bile acids. We propose that a simple enteric coated oral dosage form containing bile acid adsorbent resins will allow improved live bacterial delivery to the intestine via the oral route, a major step towards room temperature stable, easily administered and distributed vaccine pills and other bacterial therapeutics. PMID:19490986

  13. Purification Techniques of Bacteriocins from Lactic Acid Bacteria and Other Gram-Positive Bacteria

    Saavedra, Lucila; Sesma, Fernando

    The search for new antimicrobial peptides produced by lactic acid ­bacteria and other Gram-positive microorganisms has become an interesting field of research in the past decades. The fact that bacteriocins are active against numerous foodborne and human pathogens, are produced by generally regarded as safe (GRAS) microorganisms, and are readily degraded by proteolytic host systems makes them attractive candidates for biotechnological applications. However, before suggesting or choosing a new bacteriocin for future technology developments, it is necessary to elucidate its biochemical structure and its mode of action, which may be carried out once the bacteriocin is purified to homogeneity. This chapter focuses on describing the main strategies used for the purification of numerous bacteriocins.

  14. PROBIOTIC POTENTIALS AMONG LACTIC ACID BACTERIA ISOLATED FROM CURD

    Shruthy VV

    2011-02-01

    Full Text Available Curd is a commonly used fermented milk product in India since time immemorial. The scientific use of curd as a source of probiotic (good bacteria for health has not been much examined. The yougurt (curd containing probiotics is in Indian market and highly acclaimed. Therefore the status of curd as a source of probiotics is in question and requires scientific examination of its content, so the study was carried out. Probiotic potentials of two bacterial isolates from 20 different curd samples were identified as Lactobacillus spp. by the determination of morphological, cultural, physiological and biochemical characteristics, were investigated. The antibacterial potential against diarrhoegenic bacterial pathogens was also examined. The reference strain used was Lactobacillus acidophilus, MTCC 447. The percentage survivability of the strains at pH 3.5, was found to be satisfactory (>90%. Bile salt resistance (0.3% sodium thioglycollate was found to be between 80.41% and 83.2%. The pH decrease of the strains with time showed slow acidification activity. The lactic acid production of the strains ranges from 1.83 ± 0.12 to 3.93 ± 0.07 g. The strains were β-galactosidase producer and were resistant to principal antibiotics tested. But the absence of plasmids showed that they are intrinsically resistant or chromosome encoded. Strains showed maximum inhibition zone against V. cholerae O139 (13.67 ± 0.57 to 15.33 ± 0.57 mm in comparison to other diarrhoeagenic bacteria. Only 10% of the examined curd samples had probiotic bacteria. Isolated strains of Lactobacillus spp. showed satisfactory probiotic potentials in comparison with reference strains and with antibacterial activity against diarrhoeagenic pathogens and thus maybe useful in the management of diarrhoea and also in functional food industry.

  15. Interactions between Cooccurring Lactic Acid Bacteria in Honey Bee Hives.

    Rokop, Z P; Horton, M A; Newton, I L G

    2015-10-01

    In contrast to the honey bee gut, which is colonized by a few characteristic bacterial clades, the hive of the honey bee is home to a diverse array of microbes, including many lactic acid bacteria (LAB). In this study, we used culture, combined with sequencing, to sample the LAB communities found across hive environments. Specifically, we sought to use network analysis to identify microbial hubs sharing nearly identical operational taxonomic units, evidence which may indicate cooccurrence of bacteria between environments. In the process, we identified interactions between noncore bacterial members (Fructobacillus and Lactobacillaceae) and honey bee-specific "core" members. Both Fructobacillus and Lactobacillaceae colonize brood cells, bee bread, and nectar and may serve the role of pioneering species, establishing an environment conducive to the inoculation by honey bee core bacteria. Coculture assays showed that these noncore bacterial members promote the growth of honey bee-specific bacterial species. Specifically, Fructobacillus by-products in spent medium supported the growth of the Firm-5 honey bee-specific clade in vitro. Metabolic characterization of Fructobacillus using carbohydrate utilization assays revealed that this strain is capable of utilizing the simple sugars fructose and glucose, as well as the complex plant carbohydrate lignin. We tested Fructobacillus for antibiotic sensitivity and found that this bacterium, which may be important for establishment of the microbiome, is sensitive to the commonly used antibiotic tetracycline. Our results point to the possible significance of "noncore" and environmental microbial community members in the modulation of honey bee microbiome dynamics and suggest that tetracycline use by beekeepers should be limited. PMID:26253685

  16. Immunomodulation of monocytes by probiotic and selected lactic Acid bacteria.

    Jensen, Hanne; Drømtorp, Signe Marie; Axelsson, Lars; Grimmer, Stine

    2015-03-01

    Some lactic acid bacteria (LAB), especially bacteria belonging to the genus Lactobacillus, are recognized as common inhabitants of the human gastrointestinal tract and have received considerable attention in the last decades due to their postulated health-promoting effects. LAB and probiotic bacteria can modulate the host immune response. However, much is unknown about the mediators and mechanisms responsible for their immunological effect. Here, we present a study using cytokine secretion from the monocytic cell line THP-1 and NF-κB activation in the monocytic cell line U937-3xkB-LUC to elucidate immune stimulating abilities of LAB in vitro. In this study, we investigate both commercially available and potential probiotic LAB strains, and the role of putative surface proteins of L. reuteri using mutants. L. reuteri strains induced the highest cytokine secretion and the highest NF-κB activation, whereas L. plantarum strains and L. rhamnosus GG were low inducers/activators. One of the putative L. reuteri surface proteins, Hmpref0536_10802, appeared to be of importance for the stimulation of THP-1 cells and the activation of NF-κB in U937-3xkB-LUC cells. Live and UV-inactivated preparations resulted in different responses for two of the strains investigated. Our results add to the complexity in the interaction between LAB and human cells and suggest the possible involvement of secreted pro- and anti-inflammatory mediators of LAB. It is likely that it is the sum of bacterial surface proteins and bacterial metabolites and/or secreted proteins that induce cytokine secretion in THP-1 cells and activate NF-κB in U937-3xkB-LUC cells in this study. PMID:25331988

  17. STUDY ON PROBIOTIC POTENTIAL AND LABORATORY SCALE PRODUCTION OF LACTIC ACID BACTERIA

    Ambule A.H.; Timande S.P; Soni S.B

    2012-01-01

    Lactic acid bacteria were isolated from dairy food. They were identified on the basis of theirmorphological, cultural and biochemical characterastics.The cell free supernatant of lactic acid bacteria were ableto inhibit the growth ofE.coli,Klebsiella aerogens,Salmonella spp. , S.aureus, P.mirabilies and Ps .aeruginosa.The probiotic properties of isolate of lactic acid bacteria (LAB-VI) were investigated. The LAB-VI wassusceptible to antibiotics like ampicillin, gentamycin, ciprofloxacin, oflo...

  18. Growth inhibition of Streptococcus mutans by cellular extracts of human intestinal lactic acid bacteria.

    Ishihara, K; Miyakawa, H; Hasegawa, A.; Takazoe, I; Kawai, Y.

    1985-01-01

    The in vitro growth of Streptococcus mutans was completely inhibited by water-soluble extracts from cells of various intestinal lactic acid bacteria identified as Streptococcus faecium, Streptococcus equinus, Lactobacillus fermentum, and Lactobacillus salivarius. The growth inhibition was dependent on the concentrations of the extracts. In contrast, the extracts did not inhibit the growth of the major indigenous intestinal lactic acid bacteria isolated from humans. These lactic acid bacteria ...

  19. Perspectives of engineering lactic acid bacteria for biotechnological polyol production.

    Monedero, Vicente; Pérez-Martínez, Gaspar; Yebra, María J

    2010-04-01

    Polyols are sugar alcohols largely used as sweeteners and they are claimed to have several health-promoting effects (low-caloric, low-glycemic, low-insulinemic, anticariogenic, and prebiotic). While at present chemical synthesis is the only strategy able to assure the polyol market demand, the biotechnological production of polyols has been implemented in yeasts, fungi, and bacteria. Lactic acid bacteria (LAB) are a group of microorganisms particularly suited for polyol production as they display a fermentative metabolism associated with an important redox modulation and a limited biosynthetic capacity. In addition, LAB participate in food fermentation processes, where in situ production of polyols during fermentation may be useful in the development of novel functional foods. Here, we review the polyol production by LAB, focusing on metabolic engineering strategies aimed to redirect sugar fermentation pathways towards the synthesis of biotechnologically important sugar alcohols such as sorbitol, mannitol, and xylitol. Furthermore, possible approaches are presented for engineering new fermentation routes in LAB for production of arabitol, ribitol, and erythritol. PMID:20180114

  20. Lactic acid bacteria as adjuvants for sublingual allergy vaccines.

    Van Overtvelt, Laurence; Moussu, Helene; Horiot, Stéphane; Samson, Sandrine; Lombardi, Vincent; Mascarell, Laurent; van de Moer, Ariane; Bourdet-Sicard, Raphaëlle; Moingeon, Philippe

    2010-04-01

    We compared immunomodulatory properties of 11 strains of lactic acid bacteria as well as their capacity to enhance sublingual immunotherapy efficacy in a murine asthma model. Two types of bacterial strains were identified, including: (i) potent inducers of IL-12p70 and IL-10 in dendritic cells, supporting IFN-gamma and IL-10 production in CD4+ T cells such as Lactobacillus helveticus; (ii) pure Th1 inducers such as L. casei. Sublingual administration in ovalbumin-sensitized mice of L. helveticus, but not L. casei, reduced airways hyperresponsiveness, bronchial inflammation and proliferation of specific T cells in cervical lymph nodes. Thus, probiotics acting as a Th1/possibly Treg, but not Th1 adjuvant, potentiate tolerance induction via the sublingual route. PMID:20175969

  1. Variations in prebiotic oligosaccharide fermentation by intestinal lactic acid bacteria.

    Endo, Akihito; Nakamura, Saki; Konishi, Kenta; Nakagawa, Junichi; Tochio, Takumi

    2016-03-01

    Prebiotic oligosaccharides confer health benefits on the host by modulating the gut microbiota. Intestinal lactic acid bacteria (LAB) are potential targets of prebiotics; however, the metabolism of oligosaccharides by LAB has not been fully characterized. Here, we studied the metabolism of eight oligosaccharides by 19 strains of intestinal LAB. Among the eight oligosaccharides used, 1-kestose, lactosucrose and galactooligosaccharides (GOSs) led to the greatest increases in the numbers of the strains tested. However, mono- and disaccharides accounted for more than half of the GOSs used, and several strains only metabolized the mono- and di-saccharides in GOSs. End product profiles indicated that the amounts of lactate produced were generally consistent with the bacterial growth recorded. Oligosaccharide profiling revealed the interesting metabolic manner in Lactobacillus paracasei strains, which metabolized all oligosaccharides, but left sucrose when cultured with fructooligosaccharides. The present study clearly indicated that the prebiotic potential of each oligosaccharide differs. PMID:26888650

  2. Phenolic acid degradation potential and growth behavior of lactic acid bacteria in sunflower substrates.

    Fritsch, Caroline; Heinrich, Veronika; Vogel, Rudi F; Toelstede, Simone

    2016-08-01

    Sunflower flour provides a high content of protein with a well-balanced amino acid composition and is therefore regarded as an attractive source for protein. The use for human nutrition is hindered by phenolic compounds, mainly chlorogenic acid, which can lead under specific circumstances to undesirable discolorations. In this study, growth behavior and degradation ability of chlorogenic acid of four lactic acid bacteria were explored. Data suggested that significant higher fermentation performances on sunflower flour as compared to sunflower protein concentrate were reached by Lactobacillus plantarum, Pediococcus pentosaceus, Lactobacillus gasseri and Bifidobacterium animalis subsp. lactis. In fermentation with the latter two strains reduced amounts of chlorogenic acid were observed in sunflower flour (-11.4% and -19.8%, respectively), which were more pronounced in the protein concentrate (-50.7% and -95.6%, respectively). High tolerances against chlorogenic acid and the cleavage product quinic acid with a minimum inhibitory concentration (MIC) of ≥20.48 mg/ml after 48 h were recorded for all strains except Bifidobacterium animalis subsp. lactis, which was more sensitive. The second cleavage compound, caffeic acid revealed a higher antimicrobial potential with MIC values of 0.64-5.12 mg/ml. In this proof of concept study, degradation versus inhibitory effect suggest the existence of basic mechanisms of interaction between phenolic acids in sunflower and lactic acid bacteria and a feasible way to reduce the chlorogenic acid content, which may help to avoid undesired color changes. PMID:27052717

  3. Probiotic lactic acid bacteria for applications in vegetarian food products

    Charernjiratrakul, W.

    2007-07-01

    Full Text Available Total of 225 isolates of lactic acid bacteria were isolated from 152 samples of various fermented foods. The strains were investigated for their probiotic properties based on stability in bile salt (0.30% and high acidity (pH 3, growth under both aerobic and anaerobic conditions, ability to grow without vitamin B12. According to the above criteria, 40 isolates were selected. Using an agar spot method, 16 isolates were able to inhibit Salmonella typhimurium, S. typhi, S. enteritidis, S. paratyphi and 4 strains of E. coli O157 : H7 as clear zone greater than 10 mm. Moreover, utilization of protein or fat or starch was also considered. Only 5 isolates were able to utilize protein and further selected for antibiotics sensitivity test. The selected isolates were susceptible to following antibiotics: ampicillin, chloramphenicol, erythromycin , kanamycin, tetracycline and vancomycin; however they were resistant to ceptazidime and norfloxacin. They all showed better growth in vegetarian medium (coconut juice medium than MRS medium both under static and shaking conditions. Five active isolates were identified as Lactobacillus plantarum LL13, LN18, LP11, LS35 and Pediococcus pentosaceus LT02 by API 50 CH system. All cultures grew well in carrot juice by reducing pH from 6.4 to below 4.0 after 24 h of fermentation at 35oC. The lactic cultures in fermented carrot juice lost their viability about 2 log cycles after 15 days of cold storage at 4oC.

  4. Kinetic Analysis of Strains of Lactic Acid Bacteria and Acetic Acid Bacteria in Cocoa Pulp Simulation Media toward Development of a Starter Culture for Cocoa Bean Fermentation ▿

    Lefeber, Timothy; Janssens, Maarten; Camu, Nicholas; De Vuyst, Luc

    2010-01-01

    The composition of cocoa pulp simulation media (PSM) was optimized with species-specific strains of lactic acid bacteria (PSM-LAB) and acetic acid bacteria (PSM-AAB). Also, laboratory fermentations were carried out in PSM to investigate growth and metabolite production of strains of Lactobacillus plantarum and Lactobacillus fermentum and of Acetobacter pasteurianus isolated from Ghanaian cocoa bean heap fermentations, in view of the development of a defined starter culture. In a first step, a...

  5. Antimicrobial properties of lactic acid bacteria isolated from uruguayan artisan cheese

    Martín Fraga Cotelo; Karen Perelmuter Schein; Sheila Solange Giacaman Salvo; Pablo Miguel Zunino Abirad; Silvana Beatriz Carro Techera

    2013-01-01

    Uruguayan artisan cheese is elaborated with raw milk and non-commercial starters. The associated native microbiota may include lactic acid bacteria and also potentially pathogenic bacteria. Lactic acid bacteria were isolated from artisan cheese, raw milk, and non-commercial starter cultures, and their potential bacteriocin production was assessed. A culture collection of 509 isolates was obtained, and five isolates were bacteriocin-producers and were identified as Enterococcus durans,Lactobac...

  6. Naturally fermented Jijelian black olives: microbiological characteristics and isolation of lactic acid bacteria

    Karam, Nour-Eddine; Leghouchi, Essaid; Boudjerda, Jamel; Idoui, Tayeb

    2009-01-01

    A study of the microflora of traditionally fermented black olives in Eastern Algeria is presented. A count of the following microbial groups was carried out: mesophilic bacteria, enterobacteria, lactic acid bacteria (LAB), staphylococci and yeast. In a second phase, the identification and assessment of the technological traits of LAB was performed. Seventeen lactic acid bacteria were isolated and identified. These isolates were represented by two genera: Lactobacillus and Leuconostoc. The res...

  7. Isolation and characterization of lactic acid bacteria and yeasts from the Brazilian grape sourdough

    Krischina Singer Aplevicz; Jaciara Zarpellon Mazo; Eunice Cassanego Ilha; Andréia Zilio Dinon; Ernani Sebastião Sant´Anna

    2014-01-01

    Sourdough is a mixture of flour and water fermented by lactic acid bacteria and yeast, with a large use in bakery products. This study was developed with Brazilian grape (Niagara rosada) sourdough obtained from spontaneous fermentation. The aim of this work was to characterize genotypic and phenotypically lactic acid bacteria and yeasts isolated from sourdough. The phenotypic identification for bacteria and yeasts was performed by using the kit API50CHL and 20CAUX and the genotypic characteri...

  8. Myosin-cross-reactive antigens from four different lactic acid bacteria are fatty acid hydratases.

    Yang, Bo; Chen, Haiqin; Song, Yuanda; Chen, Yong Q; Zhang, Hao; Chen, Wei

    2013-01-01

    The 67 kDa myosin-cross-reactive antigen (MCRA) is a member of the MCRA family of proteins present in a wide range of bacteria and was predicted to have fatty acid isomerase function. We have now characterised the catalytic activity of MCRAs from four LAB stains, including Lactobacillus rhamnosus LGG, L. plantarum ST-III, L. acidophilus NCFM and Bifidobacterium animalis subsp. lactis BB-12. MCRA genes from these strains were cloned and expressed in Escherichia coli, and the recombinant protein function was analysed with lipid profiles by GC-MS. The four MCRAs catalysed the conversion of linoleic acid and oleic acid to their respective 10-hydroxy derivatives, which suggests that MCRA proteins catalyse the first step in conjugated linoleic acid production. This is the first report of MCRA from L. rhamnosus with such catalytic function. PMID:22955678

  9. Activity of capryloyl collagenic acid against bacteria involved in acne.

    Fourniat, J; Bourlioux, P

    1989-12-01

    Synopsis Capryloyl collagenic acid (Lipacide C8Co) has similar bacteriostatic activity in vitro to that of benzoyl peroxide towards the bacteria found in acne lesions (Staphylococcus aureus, Staphylococcus epidermidis and Propionibacterium acnes) (MIC between 1 and 4 mg ml(-1) for C8Co, and between 0.5 and 5 mg ml(-1) for benzoyl peroxide). The presence of Emulgine M8 did not affect the bacteriostatic activity of C8Co. A 4% w/v solution of C8Co (incorporating Emulgine M8) fulfilled the criteria for an antiseptic preparation as laid down by the French Pharmacopoeia (10th Edition), and had a spectrum 5 bactericidal activity according to the French Standard AFNOR NF T 72-151. The excellent cutaneous tolerance of capryloyl collagenic acid would indicate that an aqueous solution might be of value for topical treatment of the bacterial component of acne. Résumé Activité antibactérienne de l'acide capryloyl-collagénique vis à vis des bactéries impliquées dans l'etiologie de l'acné L'acide capryloyl-collagénique (Lipacide C8Co) et le peroxyde de benzoyle présentent une activité bactériostatique in-vitroéquivalente vis à vis des espèces bactériennes retrouvées au niveau des lésions acnéiques (Staphylococcus aureus, S. epidermidis et Propionibacterium acnes) (CMI comprise entre 1 et 4 mg ml(-1) pour le lipoaminoacide, et 0,5 et 5 mg ml(-1) pour le peroxyde de benzoyle). La mise en solution aqueuse de l'acide capryloyl-collagénique en présence d'Emulgine M8 ne modifie pas son activité bactériostatique. Une telle solution, à 4% m/V d'acide capryloyl-collagénique et 5% m/V d'Emulgine M8, satisfait à l'essai d'activité des préparations antiseptiques décrit à la Pharmacopée Française (Xème Ed.) (concentration minimale antiseptique: 10% v/V, pour un temps de contact de 5 min à 32 degrees C entre les germes tests et la solution diluée en eau distillée), et posséde une activité bactéricide antiseptique spectre 5 conforme à la norme AFNOR NF T

  10. Isolation and characterisation of lactic acid bacteria from donkey milk.

    Soto Del Rio, Maria de Los Dolores; Andrighetto, Christian; Dalmasso, Alessandra; Lombardi, Angiolella; Civera, Tiziana; Bottero, Maria Teresa

    2016-08-01

    During the last years the interest in donkey milk has increased significantly mainly because of its compelling functional elements. Even if the composition and nutritional properties of donkey milk are known, its microbiota is less studied. This Research Communication aimed to provide a comprehensive characterisation of the lactic acid bacteria in raw donkey milk. RAPD-PCR assay combined with 16S rDNA sequencing analysis were used to describe the microbial diversity of several donkey farms in the North West part of Italy. The more frequently detected species were: Lactobacillus paracasei, Lactococcus lactis and Carnobacterium maltaromaticum. Less abundant genera were Leuconostoc, Enterococcus and Streptococcus. The yeast Kluyveromyces marxianus was also isolated. The bacterial and biotype distribution notably diverged among the farms. Several of the found species, not previously detected in donkey milk, could have an important probiotic activity and biotechnological potential. This study represents an important insight to the ample diversity of the microorganisms present in the highly selective ecosystem of raw donkey milk. PMID:27600975

  11. Antimicrobial susceptibility of lactic acid bacteria isolated from Sombor cheese

    Bulajić Snežana

    2011-01-01

    Full Text Available Extensive literature data pointed out that some lactic acid bacteria (LABs, the predominant microbiota in fermented dairy products, may serve as reservoirs of antibiotic resistance genes potentially transferable to human pathogens. Hence, there is a growing interest in the possible role of Las vectors of antibiotic resistance determinants. This paper reports the susceptibility patterns of a number of Lspecies (belonging to the genera Lactococcus, Lactobacillus, and Enterococcus isolated from different batches of autochthonous Sombor cheese, traditionally made without the addition of starter cultures, and currently proposed as a candidate for PDO/PGI designation. The experimental work was performed to select strains that do not contain antibiotic resistance genes among those with desirable technological characteristics such as rapid acidification, proteolysis, ability to metabolise citrate and form aromogenic compounds. In addition, the results of these screening procedures could also indicate the types and degrees of antimicrobial resistance already present among the Lcommunity of Sombor cheese, which according to their geographically restricted areas of production, specific manufacturing process and characteristic aroma and appearance, represent a distinct ecological niche.

  12. Optimization of β-galactosidase production from lactic acid bacteria

    Carević Milica

    2015-01-01

    Full Text Available β-galactosidase, commonly known as lactase, represents commercially important enzyme that is prevalently used for lactose hydrolysis in milk and whey. To the date, it has been isolated from various sources. In this study different strains of lactic acid bacteria were assessed for their β-galactosidase productivity, and Lactobacillus acidophilus ATCC 4356 resulted with the highest production potential. Thereafter, optimal conditions for accomplishing high yields of β-galactosidase activity were determined. Maximal specific activity (1.01 IU mL-1 was accomplished after 2 days shake flask culture fermentation (150 rpm at 37ºC, with modified Man Rogosa Sharpe culture broth using lactose (2.5% as sole carbon source. Finally, in order to intensify release of intracellular β-galactosidase different mechanical and chemical methods were conducted. Nevertheless, vortexing with quartz sand (150 μm as abrasive was proven to be the most efficient method of cell disruption. The optimum temperature of obtained β-galactosidase was 45°C and the optimum range pH 6.5-7.5.

  13. Co-culture-inducible bacteriocin production in lactic acid bacteria.

    Chanos, Panagiotis; Mygind, Tina

    2016-05-01

    It is common knowledge that microorganisms have capabilities, like the production of antimicrobial compounds, which do not normally appear in ideal laboratory conditions. Common antimicrobial discovery techniques require the isolation of monocultures and their individual screening against target microorganisms. One strategy to achieve expression of otherwise hidden antimicrobials is induction by co-cultures. In the area of bacteriocin-producing lactic acid bacteria, there has been some research focusing into the characteristics of co-culture-inducible bacteriocin production and particularly the molecular mechanism(s) of such interactions. No clear relationship has been seen between bacteriocin-inducing and bacteriocin-producing microorganisms. The three-component regulatory system seems to be playing a central role in the induction, but inducing compounds have not been identified or characterized. However, the presence of the universal messenger molecule autoinducer-2 has been associated in some cases with the co-culture-inducible bacteriocin phenotype and it may play the role in the additional regulation of the three-component regulatory system. Understanding the mechanisms of induction would facilitate the development of strategies for screening and development of co-culture bacteriocin-producing systems and novel products as well as the perseverance of such systems in food and down to the intestinal tract, possibly conferring a probiotic effect on the host. PMID:27037694

  14. Removal of Paralytic Shellfish Toxins by Probiotic Lactic Acid Bacteria

    Mari Vasama

    2014-07-01

    Full Text Available Paralytic shellfish toxins (PSTs are non-protein neurotoxins produced by saltwater dinoflagellates and freshwater cyanobacteria. The ability of Lactobacillus rhamnosus strains GG and LC-705 (in viable and non-viable forms to remove PSTs (saxitoxin (STX, neosaxitoxin (neoSTX, gonyautoxins 2 and 3 (GTX2/3, C-toxins 1 and 2 (C1/2 from neutral and acidic solution (pH 7.3 and 2 was examined using HPLC. Binding decreased in the order of STX ~ neoSTX > C2 > GTX3 > GTX2 > C1. Removal of STX and neoSTX (77%–97.2% was significantly greater than removal of GTX3 and C2 (33.3%–49.7%. There were no significant differences in toxin removal capacity between viable and non-viable forms of lactobacilli, which suggested that binding rather than metabolism is the mechanism of the removal of toxins. In general, binding was not affected by the presence of other organic molecules in solution. Importantly, this is the first study to demonstrate the ability of specific probiotic lactic bacteria to remove PSTs, particularly the most toxic PST-STX, from solution. Further, these results warrant thorough screening and assessment of safe and beneficial microbes for their usefulness in the seafood and water industries and their effectiveness in vivo.

  15. Antibiotics influence on lactic acid bacteria inhibiting gastrointestinal tract

    Andreja Čanžek Majhenič

    2001-04-01

    Full Text Available Lactic acid bacteria (LAB are common inhabitants of the gastrointestinal (GI tract and have important role in maintaining the equilibrium of GI flora, which can be influenced by various factors like diets, antimicrobials and stress. Minimal inhibitory concentrations (MIC and minimal bactericidal concentrations (MBC of 6 antibiotics, commonly used in human medicine for 8 selected lactobacilli strains were determined by macrodilution and microdilution methods in liquid media and by diffusion method on agar plates. The effects of Penicillin G and Ampicillin on intestinal LAB were tested in vivoon mice as well. Lactobacilli were sensitive to Penicillin G, (penicillines and their derivatives and Erythromycin (macrolides by in vitro testing. Clyndamycin (pyranosid showed moderate inhibitory effect. All lactobacilli strains were resistant to Kanamycin and Neomycin (aminoglycosides, while L. salivarius IM 124 has shown extra resistance to Erythromycin and Clyndamycin. The influence of orally administered Ampicillin showed no significant influence on LAB count in mice faeces. The effect of Penicillin G on mice LAB total count was significant, while no effect of orally administered lactobacilli was determined.

  16. Engineering strategies aimed at control of acidification rate of lactic acid bacteria

    Martinussen, Jan; Solem, Christian; Holm, Anders Koefoed;

    2013-01-01

    The ability of lactic acid bacteria to produce lactic acid from various sugars plays an important role in food fermentations. Lactic acid is derived from pyruvate, the end product of glycolysis and thus a fast lactic acid production rate requires a high glycolytic flux. In addition to lactic acid......, alternative end products - ethanol, acetic acid and formic acid - are formed by many species. The central role of glycolysis in lactic acid bacteria has provoked numerous studies aiming at identifying potential bottleneck(s) since knowledge about flux control could be important not only for optimizing food...... fermentation processes, but also for novel applications of lactic acid bacteria, such as cell factories for the production of green fuels and chemicals. With respect to the control and regulation of the fermentation mode, some progress has been made, but the question of which component(s) control the main...

  17. Activity of H(+)-ATPase in ruminal bacteria with special reference to acid tolerance.

    Miwa, T.; Esaki, H; Umemori, J; Hino, T.

    1997-01-01

    Batch culture experiments showed that permeabilized cells and membranes of Ruminococcus albus and Fibrobacter succinogenes, acid-intolerant celluloytic bacteria, have only one-fourth to one-fifth as much H(+)-ATPase as Megasphaera elsdenii and Streptococcus bovis, which are relatively acid tolerant. Even in the cells grown in continuous culture at pH 7.0, the acid-intolerant bacteria contained less than half as much H(+)-ATPase as the acid-tolerant bacteria. The amounts of H(+)-ATPase in the ...

  18. Examination of Lactic Acid Bacteria to Secretion of Bacteriocins

    Maira Urazova

    2014-01-01

    Full Text Available Introduction: Bacteriocins produced by lactic acid bacteria (LAB have the potential to cover a very broad field of applications, including the food industry and the medical sector. In the food industry, bacteriocinogenic LAB strains can be used as starter cultures, co-cultures, and bioprotective cultures, which would be used to improve food quality and safety. In the medical sector, bacteriocins of probiotic LAB might play a role in interactions, which take place in human gastrointestinal tract, and contribute to gut health. The aim of this study was the examine the effect of LAB antimicrobial activity. Methods: LAB were isolated from different commercial and home made products, such as kazy and sour cream. To screen for bacteriocin producing LAB, we used an agar diffusion bioassay, described in a previous study by Dr. Yang, with three modifications in cell-free supernatant (CFS. First we had a clear supernatant, second we adjusted the CFS to pH 6.0 to eliminate acids antimicrobial effects, and third the CFS pH 6.0 was treated with catalase to exclude the action of H2O2 and confirm action of bacteriocin-like substances. Pathogenic S.marcescens, E. coli, S.aureus cultures were used as indicators. Results: Screening of 95 strains of LAB through deferred antagonism to six indicator cultures showed that all of the selected strains had a high value of antibacterial activity. However, CFS of only 50 strains retained their antimicrobial activity, and 10 of them lost this activity in the second modification of CFS with pH 6.0 to test culture S.marcescens, which confirmed the acidic nature of antimicrobial activity of CFS. Lb.rhamnosus (P-1, Lb.fermentum (N-6, and Lc.lactis (7M lost antibacterial activity in the presence of the catalase. All modifications of CFS of three strains: Lb.pentosus (16al, Lb.pentosus (P-2, and Pediococcusacidilactici (8 retained inhibitory activity to E.coli and S. aureus. Supernatants of only Lactococcusgarvieae (10a and

  19. Production of γ-Amino Butyric Acid in Tea Leaves wit Treatment of Lactic Acid Bacteria

    Watanabe, Yuko; Hayakawa, Kiyoshi; Ueno, Hiroshi

    Lactic acid bacteria was searched for producing termented tea that contained a lot of γ-amino butyric acid(GABA). Also examined were the growth condition, GABA production and changes in catechin contents in the tea leaves. Lactobacillus brevis L12 was found to be suitable for the production of fermented tea since it gave as much GABA as gabaron tea when tea leaves being suspended with water at 10% and incubated for 4 days at 25°C. The amount of GABA produced was more than calculated based upon the content of glutamic acid in tea leaves. It is probable to assume that glutamate derived from glutamine and theanine is converted into GABA.

  20. TECHNOLOGICAL AND FUNCTIONAL PROPERTIES OF LACTIC ACID BACTERIA: THE IMPORTANCE OF THESE MICROORGANISMS FOR FOOD

    Amanda de Souza Motta; Melina Da Silva Mesquita Gomes

    2015-01-01

    Eacters of coccus or rods Gram-positive, catalase negative, non-sporulating, which produce lactic acid as the major end product during the fermentation of carbohydrates. When applied on food, provides beneficial effects to consumers through its functional and technological properties. With this the present review article, explore the potential application of lactic acid bacteria in food. The following genera are considered the principal lactic acid bacteria: Aerococcus, Carnobacterium, Entero...

  1. Effect of fermented broth from lactic acid bacteria on pathogenic bacteria proliferation.

    Gutiérrez, S; Martínez-Blanco, H; Rodríguez-Aparicio, L B; Ferrero, M A

    2016-04-01

    In this study, the effect that 5 fermented broths of lactic acid bacteria (LAB) strains have on the viability or proliferation and adhesion of 7 potentially pathogenic microorganisms was tested. The fermented broth from Lactococcus lactis C660 had a growth inhibitory effect on Escherichia coli K92 that reached of 31%, 19% to Pseudomonas fluorescens, and 76% to Staphylococcus epidermidis. The growth of Staph. epidermidis was negatively affected to 90% by Lc. lactis 11454 broth, whereas the growth of P. fluorescens (25%) and both species of Staphylococcus (35% to Staphylococcus aureus and 76% to Staph. epidermidis) were inhibited when they were incubated in the presence of Lactobacillus casei 393 broth. Finally, the fermented broth of Lactobacillus rhamnosus showed an inhibitory effect on growth of E. coli K92, Listeria innocua, and Staph. epidermidis reached values of 12, 28, and 76%, respectively. Staphylococcus epidermidis was the most affected strain because the effect was detected from the early stages of growth and it was completely abolished. The results of bacterial adhesion revealed that broths from Lc. lactis strains, Lactobacillus paracasei, and Lb. rhamnosus caused a loss of E. coli K92 adhesion. Bacillus cereus showed a decreased of adhesion in the presence of the broths of Lc. lactis strains and Lb. paracasei. Listeria innocua adhesion inhibition was observed in the presence of Lb. paracasei broth, and the greatest inhibitory effect was registered when this pathogenic bacterium was incubated in presence of Lc. lactis 11454 broth. With respect to the 2 Pseudomonas, we observed a slight adhesion inhibition showed by Lactobacillus rhamnosus broth against Pseudomonas putida. These results confirm that the effect caused by the different LAB assayed is also broth- and species-specific and reveal that the broth from LAB tested can be used as functional bioactive compounds to regulate the adhesion and biofilm synthesis and ultimately lead to preventing food and

  2. Solution Structure and Backbone Dynamics of Human Liver Fatty Acid Binding Protein: Fatty Acid Binding Revisited

    Cai, Jun; Lücke, Christian; Chen, Zhongjing; Qiao, Ye; Klimtchuk, Elena; Hamilton, James A.

    2012-01-01

    Liver fatty acid binding protein (L-FABP), a cytosolic protein most abundant in liver, is associated with intracellular transport of fatty acids, nuclear signaling, and regulation of intracellular lipolysis. Among the members of the intracellular lipid binding protein family, L-FABP is of particular interest as it can i), bind two fatty acid molecules simultaneously and ii), accommodate a variety of bulkier physiological ligands such as bilirubin and fatty acyl CoA. To better understand the p...

  3. Revisiting formic acid decomposition on metallic powder catalysts: Exploding the HCOOH decomposition volcano curve

    Tang, Yadan; Roberts, Charles A.; Perkins, Ryan T.; Wachs, Israel E.

    2016-08-01

    This study revisits the classic volcano curve for HCOOH decomposition by metal catalysts by taking a modern catalysis approach. The metal catalysts (Au, Ag, Cu, Pt, Pd, Ni, Rh, Co and Fe) were prepared by H2 reduction of the corresponding metal oxides. The number of surface active sites (Ns) was determined by formic acid chemisorption. In situ IR indicated that both monodentate and bidentate/bridged surface HCOO* were present on the metals. Heats of adsorption (ΔHads) for surface HCOO* values on metals were taken from recently reported DFT calculations. Kinetics for surface HCOO* decomposition (krds) were determined with TPD spectroscopy. Steady-state specific activity (TOF = activity/Ns) for HCOOH decomposition over the metals was calculated from steady-state activity (μmol/g-s) and Ns (μmol/g). Steady-state TOFs for HCOOH decomposition weakly correlated with surface HCOO* decomposition kinetics (krds) and ΔHads of surface HCOO* intermediates. The plot of TOF vs. ΔHads for HCOOH decomposition on metal catalysts does not reproduce the classic volcano curve, but shows that TOF depends on both ΔHads and decomposition kinetics (krds) of surface HCOO* intermediates. This is the first time that the classic catalysis study of HCOOH decomposition on metallic powder catalysts has been repeated since its original publication.

  4. Selection of Lactic Acid Bacteria as Probiotic Candidate for Chicken

    F. Hamida

    2015-08-01

    Full Text Available Lactic acid bacteria (LAB regarded as safe microorganisms; they can naturally live in gastrointestinal tract, so appropriately used as a probiotic for chicken. This study aimed to select six isolates of LAB (E1223, E3, E4, E5, E7, and E8 to obtain the isolates potentially as probiotic candidate for chicken. The six isolates were derived from spontaneous fermented corn obtained from Laboratory of Animal Biotechnology and Biomedical, PPSHB, Bogor Agricultural University, Indonesia. LAB isolates were tested their susceptibility to antibiotics (bambermycin, erythromycin, chloramphenicol, and tetracycline then were examined in vitro for their tolerance to gastrointestinal pH (2, 3, 4, and 7.2 and 0.5% bile salt condition, antimicrobial activity against Salmonella enteritidis and Enterococcus casseliflavus, and ability to adhere to chicken ileal cells. The results showed the isolates E5, E7, and E8 were sensitive to tetracycline and chloramphenicol, they could survive at pH 2, 3, 4, and 7.2, could survive at 0.5% bile salts, produced antimicrobial activity, and able to adhere to ileal cells (9.40±0.00 Log CFU/cm2 of E8 and were significantly (P<0.05 higher than those of control (5.30±0.14 Log CFU/cm2. In conclusion, this study showed that isolate E8 had better potential compared to isolates E5 and E7 in most in vitro assays as a probiotic candidate for chicken. E5, E7, and E8 were closely related with Pediococcus pentosaceus based on 16S rRNA gene.

  5. Resistance to antibiotics in Lacid acid bacteria - strain Lactococcus

    Filipić Brankica

    2015-01-01

    Full Text Available Lactic acid bacteria (LAB are widely used in the food industry, especially in the production of fermented dairy products and meat. The most studied species among Lis Lactococcus lactis. L. lactis strains are of great importance in the production of fermented dairy products such as yogurt, butter, fresh cheese and some kind of semi-hard cheese. Although L. lactis acquired the „Generally Regarded As Safe“ (GRAS status, many investigations indicated that lactococci may act as reservoirs of antibiotic resistance genes, which could be transferred to other bacterial species in human gastrointestinal tract includ­ing pathogens. The genome analysis of L. lactis indicated the presence of at least 40 putative drug transporter genes, and only four multidrug resistance (MDR transporters are functionally characterized: LmrA, LmrP, LmrCD i CmbT. LmrA is the first described MDR transporter in prokaryotes. LmrCD is responsible for resistance to cholate, which is an integral part of human bile and LmrCD is important for intestinal survival of lactococci that are used as probiotics. Secondary multidrug transporter LmrP confers resistance to lincosamides, macrolides, streptogramins and tetracyclines. CmbT protein has an effect on the host cell resistance to lincomycin, sulfadiazine, streptomycin, rifampicin, puromycin and sulfametox­azole. Since the food chain is an important way of transmitting resistance genes in human and animal population, it is of great importance to study the mechanisms of resistance in lactococci and other LAB, intended for the food industry. [Projekat Ministarstva nauke Republike Srbije, br. 173019: Izučavanje gena i molekularnih mehanizama u osnovi probiotičke aktivnosti bakterija mlečne kiseline izolovanih sa područja Zapadnog Balkana

  6. Hypolipidemic effects of lactic acid bacteria fermented cereal in rats

    Banjoko Immaculata

    2012-12-01

    Full Text Available Abstract Background The objectives of the present study were to investigate the efficacy of the mixed culture of Lactobacillus acidophilus (DSM 20242, Bifidobacterium bifidum (DSM 20082 and Lactobacillus helveticus (CK60 in the fermentation of maize and the evaluation of the effect of the fermented meal on the lipid profile of rats. Methods Rats were randomly assigned to 3 groups and each group placed on a Diet A (high fat diet into which a maize meal fermented with a mixed culture of Lb acidophilus (DSM 20242, B bifidum (DSM 20082 and Lb helveticus (CK 60 was incorporated, B (unfermented high fat diet or C (commercial rat chow respectively after the first group of 7 rats randomly selected were sacrificed to obtain the baseline data. Thereafter 7 rats each from the experimental and control groups were sacrificed weekly for 4 weeks and the plasma, erythrocytes, lipoproteins and organs of the rats were assessed for cholesterol, triglyceride and phospholipids. Results Our results revealed that the mixed culture of Lb acidophilus (DSM 20242, B bifidum (DSM 20082 and Lb helveticus (CK 60 were able to grow and ferment maize meal into ‘ogi’ of acceptable flavour. In addition to plasma and hepatic hypercholesterolemia and hypertriglyceridemia, phospholipidosis in plasma, as well as cholesterogenesis, triglyceride constipation and phospholipidosis in extra-hepatic tissues characterized the consumption of unfermented hyperlipidemic diets. However, feeding the animals with the fermented maize diet reversed the dyslipidemia. Conclusion The findings of this study indicate that consumption of mixed culture lactic acid bacteria (Lb acidophilus (DSM 20242, Bifidobacterium bifidum (DSM 20082 and Lb helveticus (CK 60 fermented food results in the inhibition of fat absorption. It also inhibits the activity of HMG CoA reductase. This inhibition may be by feedback inhibition or repression of the transcription of the gene encoding the enzyme via activation of the

  7. The Effects of Lactic Acid Bacteria and Lactic Acid Bacteria+Enzyme Mixture Silage Inoculants on Maize Silage Fermentation and Nutrient Digestibility in Lambs

    M. L. Ozduven

    2005-01-01

    Full Text Available This study was carried out to determine the effects of lactic acid bacteria and lact ic acidbacteria+enzyme mixture inoculants as silage additives, on the fermentation, aerobic stability, cell wallcontent, and nutrient digestibility in lambs of maize silages. Pioneer 1174 (Iowa, USA, and Maize -All(Alltech, UK were used as lactic acid bacteria and lactic acid bacteria+enzyme mixture inoculants. Plantmaterials were fermented for 60 days in bunker type silos. Aerobic stability test was applied to all silosopened in the end of fermentation period. Relating to silage fermentation analysis of pH, ammonia nitrogen,water soluble carbohydrate, organic acids (lactic, acetic and butyric acid were carried out andmicrobiological analyses had been done. Digestional value of crude nutritive matters of silages determinedwith classical digestive experiments. Both inoculants increased characteristics of fermentation but impairedaerobic stability of maize silages. Inoculants were not effect on the nutritient digestibility of silages. Lacticacid bacteria+enzyme mixture inoculant decreased neutral and acid detergent fiber content.

  8. Cd(II) Sorption on Montmorillonite-Humic acid-Bacteria Composites

    Du, Huihui; Chen, Wenli; Cai, Peng; Rong, Xingmin; Dai, Ke; Peacock, Caroline L.; Huang, Qiaoyun

    2016-01-01

    Soil components (e.g., clays, bacteria and humic substances) are known to produce mineral-organic composites in natural systems. Herein, batch sorption isotherms, isothermal titration calorimetry (ITC), and Cd K-edge EXAFS spectroscopy were applied to investigate the binding characteristics of Cd on montmorillonite(Mont)-humic acid(HA)-bacteria composites. Additive sorption and non-additive Cd(II) sorption behaviour is observed for the binary Mont-bacteria and ternary Mont-HA-bacteria composite, respectively. Specifically, in the ternary composite, the coexistence of HA and bacteria inhibits Cd adsorption, suggesting a “blocking effect” between humic acid and bacterial cells. Large positive entropies (68.1 ~ 114.4 J/mol/K), and linear combination fitting of the EXAFS spectra for Cd adsorbed onto Mont-bacteria and Mont-HA-bacteria composites, demonstrate that Cd is mostly bound to bacterial surface functional groups by forming inner-sphere complexes. All our results together support the assertion that there is a degree of site masking in the ternary clay mineral-humic acid-bacteria composite. Because of this, in the ternary composite, Cd preferentially binds to the higher affinity components-i.e., the bacteria. PMID:26792640

  9. Inactivation of bacteria on surfaces by sprayed slightly acidic hypochlorous acid water: in vitro experiments.

    Hakim, Hakimullah; Alam, Md Shahin; Sangsriratanakul, Natthanan; Nakajima, Katsuhiro; Kitazawa, Minori; Ota, Mari; Toyofuku, Chiharu; Yamada, Masashi; Thammakarn, Chanathip; Shoham, Dany; Takehara, Kazuaki

    2016-08-01

    The capacity of slightly acidic hypochlorous acid water (SAHW), in both liquid and spray form, to inactivate bacteria was evaluated as a potential candidate for biosecurity enhancement in poultry production. SAHW (containing 50 or 100 ppm chlorine, pH 6) was able to inactivate Escherichia coli and Salmonella Infantis in liquid to below detectable levels (≤2.6 log10 CFU/ml) within 5 sec of exposure. In addition, SAHW antibacterial capacity was evaluated by spraying it using a nebulizer into a box containing these bacteria, which were present on the surfaces of glass plates and rayon sheets. SAHW was able to inactivate both bacterial species on the glass plates (dry condition) and rayon sheets within 5 min spraying and 5 min contact times, with the exception of 50 ppm SAHW on the rayon sheets. Furthermore, a corrosivity test determined that SAHW does not corrode metallic objects, even at the longest exposure times (83 days). Our findings demonstrate that SAHW is a good candidate for biosecurity enhancement in the poultry industry. Spraying it on the surfaces of objects, eggshells, egg incubators and transport cages could reduce the chances of contamination and disease transmission. These results augment previous findings demonstrating the competence of SAHW as an anti-viral disinfectant. PMID:27052464

  10. Characterization of anti-listerial lactic acid bacteria isolated from Thai fermented fish products

    Østergaard, Anya; Embarek, Peter Karim Ben; Wedell-Neergaard, C.;

    1998-01-01

    Thai fermented fish products were screened for lactic acid bacteria capable of inhibiting Listeria sp. (Listeria innocua). Of 4150 assumed lactic acid bacteria colonies from MRS agar plates that were screened by an agar-overlay method 58 (1.4%) were positive. Forty four of these strains were...... further characterized and 43 strains were inhibitory against Listeria monocytogenes. The strains were inhibitory to other Gram- positive (lactic acid) bacteria probably because of production of bacteriocins. All 44 strains inhibited both Vibrio cholerae and Vibrio parahaemolyticus and 37 were inhibitory...... to a mesophilic fish spoilage bacterium tan Aeromonas sp.). Inhibition of Gram-negative bacteria was attributed to production of lactic acid. Most strains were identified as Lactobacillus spp., and all grew well at ambient temperatures (25-37 degrees C) and tolerated up to 6.5% NaCl. Glucose was...

  11. Bacillus spp. produce antibacterial activities against lactic acid bacteria that contaminate fuel ethanol plants

    Lactic acid bacteria (LAB) frequently contaminate commercial fuel ethanol fermentations, reducing yields and decreasing profitability of biofuel production. Microorganisms from environmental sources in different geographic regions of Thailand were tested for antibacterial activity against LAB. Fou...

  12. Molecular Characterization of Intrinsic and Acquired antibiotic resistance in lactic Acid bacteria and Bifidobacteria

    Ammor, M.S.; Flórez, A.B.; Hoek, van A.H.A.M.; Reyes-Gavilan, de los C.G.; Aarts, H.J.M.; Margolles, A.; Mayo, B.

    2008-01-01

    The minimum inhibitory concentrations (MICs) of 6 different antibiotics (chloramphenicol, clindamycin, erythromycin, streptomycin, tetracycline and vancomycin) were determined for 143 strains of lactic acid bacteria and bifidobacteria using the Etest. Different MICs were found for different species

  13. Isolation of lactic acid bacteria for its possible use in the fermentation of green algerian olives

    Nour-Eddine, Karam; Halima, Zadi-Karam; Mourad, Kacem

    2004-01-01

    This study was undertaken with the aim of obtaining lactic acid bacteria with the ability to ferment olives for possible use as starter cultures. For this reason, 32 isolates of lactic acid bacteria isolated from the spontaneous fermentation of green olives were characterized and identified on the basis of morphological and biochemical criteria. 14 of them were identified as Lactococcus lactis, 11 isolates as Lactobacillus plantarum and 7 isolates as Enterococcus sp. Of the 18 isolates examin...

  14. LACTIC ACID BACTERIA FLORA OF KONYA KUFLU CHEESE: A TRADITIONAL CHEESE FROM KONYA PROVINCE IN TURKEY

    Ziba Guley; Harun R. Uysal; Sevda Kilic

    2014-01-01

    The aim of this study was to characterize the lactic acid bacteria flora of mature Konya Kuflu cheese. Konya Kuflu cheese is a traditional blue cheese which is produced from raw milk without starter culture addition and mould growth occurs in uncontrolled conditions during its ripening. Lactic acid bacteria (LAB) isolated from 9 mature Konya Kuflu cheese samples were investigated using a combination of conventional biochemical tests, API test kits, and molecular approaches. For some isolates,...

  15. Isolation and identification of indigenous lactic acid bacteria from North Sumatra river buffalo milk

    2015-01-01

    Buffalo milk is a source of various lactic acid bacteria (LAB) which is potential as culture starter as well as the probiotic. This study was conducted to isolate and identify LAB from indigenous North Sumatra river buffalo milk. Lactic acid bacteria was isolated and grown in medium De Man Rogosa Sharpe Agar (MRSA). The isolation was conducted to obtain pure isolate. The identification of LAB was studied in terms of morphology, physiology, biochemistry and survival on low pH. Morphology test...

  16. ISOLATION AND IDENTIFICATION OF LACTIC ACID PRODUCING BACTERIA FROM CAMEL MILK

    Toqeer Ahmad, Rashida Kanwal, Izhar Hussain Athar1, Najam Ayub

    2002-01-01

    Lactic acid bacteria (LAB) were isolated from camel milk by culturing the camel milk on specific media and pure culture was obtained by sub culturing. Purification of culture was confirmed by Gram's staining and identified by different bio-chemical tests. Camel milk contains lactic acid producing bacteria including Strpptococci such as S. cremoris and S. lactis and Lactobacilli such as L. acidophilus L. acidophilus grows more rapidly in camel milk than others as its growth is supported by cam...

  17. Immune Modulation Capability of Exopolysaccharides Synthesised by Lactic Acid Bacteria and Bifidobacteria

    Hidalgo-Cantabrana, Claudio; López, Patricia; Gueimonde Fernández, Miguel; González de los Reyes-Gavilán, Clara; Suárez, Ana; Margolles Barros, Abelardo; Ruas-Madiedo, Patricia

    2012-01-01

    During recent years, the exopolysaccharides (EPS) produced by some strains of lactic acid bacteria and bifidobacteria have attracted the attention of researchers, mainly due to their potential technological applications. However, more recently, it has been observed that some of these EPS present immunomodulatory properties, which suggest a potential effect on human health. Whereas EPS from lactic acid bacteria have been studied in some detail, those of bifidobacteria largely remain uncharacte...

  18. Survival of Listeria monocytogenes, Listeria innocua, and Lactic acid bacteria species in chill brine

    Meadows, Bridget Archibald

    2004-01-01

    SURVIVAL OF LISTERIA MONOCYTOGENES, LISTERIA INNOCUA, AND LACTIC ACID BACTERIA SPECIES IN CHILL BRINES Bridget Archibald Meadows (ABSTRACT) Listeria monocytogenes is the major pathogen in ready-to-eat meat products such as deli meats and frankfurters. Contamination can occur via the salt brines that are used to cool thermally processed meats. Both L. monocytogenes and lactic acid bacteria can grow and thrive under these brine conditions, and may become competitive with each ot...

  19. A Novel Lactic Acid Bacteria Growth-stimulating Peptide from Broad Bean (Vicia faba .) Protein Hydrolysates

    Ping Xiao; Yuan Liu; Rizwan-ur-Rehman; Ran Kang; Yanping Wang

    2015-01-01

    In this study, broad bean protein hydrolysates (BPH) produced by alcalase with strong-stimulating activity for lactic acid bacteria (LAB) was first time reported. In order to obtain the key peptide that have growth-stimulating activity for lactic acid bacteria (LAB), gel filtration chromatography and Reverse Phase High Performance Liquid Chromatography (RP-HPLC) were applied to isolate and purify the peptides from BPH. Finally, F4-2 elicited the highest activity for LAB, corresponding to amin...

  20. Acetic Acid Bacteria and the Production and Quality of Wine Vinegar

    Albert Mas; María Jesús Torija; María del Carmen García-Parrilla; Ana María Troncoso

    2014-01-01

    The production of vinegar depends on an oxidation process that is mainly performed by acetic acid bacteria. Despite the different methods of vinegar production (more or less designated as either “fast” or “traditional”), the use of pure starter cultures remains far from being a reality. Uncontrolled mixed cultures are normally used, but this review proposes the use of controlled mixed cultures. The acetic acid bacteria species determine the quality of vinegar, although the final quality is a ...

  1. Adhesion of Zearalenone to the Surface of Lactic Acid Bacteria Cells

    Čvek, Domagoj; Markov, Ksenija; Frece, Jadranka; Friganović, Maja; Duraković, Lejla; Delaš, Frane

    2012-01-01

    Zearalenone is mycotoxin harmful to the health of humans and animals and is present in food and feed. Therefore, last few decades, great attention is paid to the development of biological detoxification methods with reference to the application of lactic acid bacteria in binding and removal of mycotoxins from food and feed. The aim of this work was to investigate the ability of lactic acid bacteria Lactobacillus rhamnosus GG (ATCC 53103) and Lactobacillus plantarum A1 to bind zearalenone unto...

  2. ISOLATION OF LACTIC ACID BACTERIA UNDER LOW TEMPERATURE FOR THE PREPARATION OF YOGURT

    Javid Ahmad Bhat; Mohd Irfan Naik; R.K Tenguria

    2014-01-01

    An investigation of isolation of Lactic acid bacteria was carried out under low temperature for the preparation of Yogurt by using various food supplements like carrot, ground-nut and tomato juices. Methods: Various samples of Cow milk, Skimmed milk were processed along with nutrients like Carrot, ground nut and tomato juices with Tryptone glucose yeast extract agar (TGYA) at different temperatures like 50C, 150C and 220C for the isolation of Lactic acid bacteria for the preparation of yogurt...

  3. Isolation, characterization and optimization of indigenous acetic acid bacteria and evaluation of their preservation methods

    K Beheshti-Maal

    2010-06-01

    Full Text Available Background and Objectives: Acetic acid bacteria (AAB are useful in industrial production of vinegar. The present study aims at isolation and identification of acetic acid bacteria with characterization, optimization, and evaluation of their acetic acid productivity."nMaterials and Methods: Samples from various fruits were screened for presence of acetic acid bacteria on glucose, yeast extract, calcium carbonate (GYC medium. Carr medium supplemented with bromocresol green was used for distinguishing Acetobacter from Gluconobacter. The isolates were cultured in basal medium to find the highest acetic acid producer. Biochemical tests followed by 16S rRNA and restriction analyses were employed for identification of the isolate and phylogenic tree was constructed. Bacterial growth and acid production conditions were optimized based on optimal inoculum size, pH, temperature, agitation, aeration and medium composition."nResults: Thirty-seven acetic acid bacteria from acetobacter and gluconobacter members were isolated. Acetic acid productivity yielded 4 isolates that produced higher amounts of acid. The highest producer of acid (10.03% was selected for identification. The sequencing and restriction analyses of 16S rRNA revealed a divergent strain of Acetobacter pasteurianus (Gene bank accession number # GU059865. The optimum condition for acid production was a medium composed of 2% glucose, 2% yeast extract, 3% ethanol and 3% acid acetic at inoculum size of 4% at 3L/Min aeration level in the production medium. The isolate was best preserved in GYC medium at 12oC for more than a month. Longer preservation was possible at -70oC."nConclusion: The results are suggestive of isolation of an indigenous acetic acid bacteria. Pilot plan is suggested to study applicability of the isolated strain in acetic acid production.

  4. Antimicrobial properties of lactic acid bacteria isolated from uruguayan artisan cheese

    Martín Fraga Cotelo

    2013-12-01

    Full Text Available Uruguayan artisan cheese is elaborated with raw milk and non-commercial starters. The associated native microbiota may include lactic acid bacteria and also potentially pathogenic bacteria. Lactic acid bacteria were isolated from artisan cheese, raw milk, and non-commercial starter cultures, and their potential bacteriocin production was assessed. A culture collection of 509 isolates was obtained, and five isolates were bacteriocin-producers and were identified as Enterococcus durans,Lactobacillus casei, and Lactococcus lactis. No evidence of potential virulence factors were found in E. durans strains. These are promising results in terms of using these native strains for cheese manufacture and to obtain safe products.

  5. Acetic acid bacteria in traditional balsamic vinegar: phenotypic traits relevant for starter cultures selection.

    Gullo, Maria; Giudici, Paolo

    2008-06-30

    This review focuses on acetic acid bacteria in traditional balsamic vinegar process. Although several studies are available on acetic acid bacteria ecology, metabolism and nutritional requirements, their activity as well as their technological traits in homemade vinegars as traditional balsamic vinegar is not well known. The basic technology to oxidise cooked grape must to produce traditional balsamic vinegar is performed by the so called "seed-vinegar" that is a microbiologically undefined starter culture obtained from spontaneous acetification of previous raw material. Selected starter cultures are the main technological improvement in order to innovate traditional balsamic vinegar production but until now they are rarely applied. To develop acetic acid bacteria starter cultures, selection criteria have to take in account composition of raw material, acetic acid bacteria metabolic activities, applied technology and desired characteristics of the final product. For traditional balsamic vinegar, significative phenotypical traits of acetic acid bacteria have been highlighted. Basic traits are: ethanol preferred and efficient oxidation, fast rate of acetic acid production, tolerance to high concentration of acetic acid, no overoxidation and low pH resistance. Specific traits are tolerance to high sugar concentration and to a wide temperature range. Gluconacetobacter europaeus and Acetobacter malorum strains can be evaluated to develop selected starter cultures since they show one or more suitable characters. PMID:18177968

  6. Antibacterial Activity of Some Lactic Acid Bacteria Isolated from an Algerian Dairy Product

    Abdelkader Mezaini

    2009-01-01

    Full Text Available In the present study, the antibacterial effect of 20 lactic acid bacteria isolates from a traditional cheese was investigated. 6 isolates showed antibacterial effect against Gram positive bacteria. Streptococcus thermophilus T2 strain showed the wide inhibitory spectrum against the Gram positive bacteria. Growth and bacteriocin production profiles showed that the maximal bacteriocin production, by S. thermophilus T2 cells, was measured by the end of the late-log phase (90 AU ml−1 with a bacteriocine production rate of 9.3 (AU ml−1 h−1. In addition, our findings showed that the bacteriocin, produced by S. thermophilus T2, was stable over a wide pH range (4–8; this indicates that such bacteriocin may be useful in acidic as well as nonacidic food. This preliminarily work shows the potential application of autochthonous lactic acid bacteria to improve safety of traditional fermented food.

  7. Isolation of lactic acid bacteria with potential protective culture characteristics from fruits

    Hashim, Nurul Huda; Sani, Norrakiah Abdullah

    2015-09-01

    Lactic acid bacteria are also known as beneficial microorganisms abundantly found in fermented food products. In this study, lactic acid bacteria were isolated from fresh cut fruits obtained from local markets. Throughout the isolation process from 11 samples of fruits, 225 presumptive lactic acid bacteria were isolated on MRS agar medium. After catalase and oxidase tests, 149 resulted to fit the characteristics of lactic acid bacteria. Further identification using Gram staining was conducted to identify the Gram positive bacteria. After this confirmation, the fermentation characteristics of these isolates were identified. It was found that 87 (58.4%) isolates were heterofermentative, while the rest of 62 (41.6%) are homofermentative lactic acid bacteria. Later, all these isolates were investigated for the ability to inhibit growth of Staphylococcus aureus using agar spot assay method. Seven (4.7%) isolates showed strong antagonistic capacity, while 127 (85.2%) and 8 (5.4%) isolates have medium and weak antagonistic capacity, respectively. The other 7 (4.7%) isolates indicated to have no antagonistic effect on S. aureus. Results support the potential of LAB isolated in this study which showed strong antagonistic activity against S. aureus may be manipulated to become protective cultures in food products. While the homofermentative or heterofermentative LAB can be utilized in fermentation of food and non-food products depending on the by-products required during the fermentation.

  8. Metabolic Induction of Lactic Acid Bacteria for Urea Removal

    ZHANG Su-ai; BAI Yu; LI Dong-xia; CHEN Bo-li; SONG Cun-jiang; QIAO Ming-qiang; KONG De-ling; YU Yao-ting

    2009-01-01

    Objective:This study aims to induce nonpathogenic bacteria for urea removal as a potential treatment in renal failure. Methods:Lactococus lactis MG1363 was induced by repeated exposure to urea-rich culture media, the ability to remove urea from the media was evaluated. The effect of gastroenteric environment, such as low pH, bile salt and antiagonistic properties were investigated.The antimicrobial activities on pathogenic E.coli and S.aureus in the intestinal tract and the antibiotic tolerance of the induced bacteria were also studied.Results: Induced bacteria of 50 generations could decrease the urea level from 40.01 mg/dL to 32.99 mg/dL after 24 h. The bacteria could grow after treatment at pH3.0 for 2 h and in 0.1% bile salt for 6 h, and the urea removal activity was retained in such simulated gastroenteric environment. The removal of urea was significantly enhanced to 35.8% by addition of Ni2+ to the culture medium at neutral pH. It was also found that the induced bacteria could inhibit the growth of E.coli and S.aureus, and tolerate ampicillin,gentamicin,roxithromycin,tetracycline and cefradine. The safety tests were performed by feeding normal rats with either Lactococus lactis MG1363 or induced Lactococus lactis MG1363. The two materials did not cause any changes in blood cells, blood biochemical indexes and body weight. Conclusion: These results suggest that the induced Lactococus lactis MG1363 has the potential as an oral therapy for the removal of urea in patients with renal failure.

  9. Preservation of acidified cucumbers with a natural preservative combination of fumaric acid and allyl isothiocyanate that target lactic acid bacteria and yeasts

    Without the addition of preservative compounds cucumbers acidified with 150 mM acetic acid with pH adjusted to 3.5 typically undergo fermentation by lactic acid bacteria. Fumaric acid (20 mM) inhibited growth of Lactobacillus plantarum and the lactic acid bacteria present on fresh cucumbers, but sp...

  10. Metabolic engineering of lactic acid bacteria for the production of nutraceuticals

    Hugenholtz, J.; Sybesma, W.; Groot, M.N.; Wisselink, W.; Ladero, V.; Burgess, K.; Sinderen, van D.; Piard, J.C.; Eggink, G.; Smid, E.J.; Savoy, G.; Sesma, F.; Jansen, T.; Hols, P.; Kleerebezem, M.

    2002-01-01

    Lactic acid bacteria display a relatively simple and well-described metabolism where the sugar source is converted mainly to lactic acid. Here we will shortly describe metabolic engineering strategies on the level of sugar metabolism, that lead to either the efficient re-routing of the lactococcal s

  11. Lactic acid bacteria as a cell factory for riboflavin production

    Thakur, Kiran; Tomar, Sudhir Kumar; De, Sachinandan

    2015-01-01

    Summary Consumers are increasingly becoming aware of their health and nutritional requirements, and in this context, vitamins produced in situ by microbes may suit their needs and expectations. B groups vitamins are essential components of cellular metabolism and among them riboflavin is one of the vital vitamins required by bacteria, plants, animals and humans. Here, we focus on the importance of microbial production of riboflavin over chemical synthesis. In addition, genetic abilities for r...

  12. Local domestication of lactic acid bacteria via cassava beer fermentation

    Colehour, Alese M.; Meadow, James F.; Liebert, Melissa A.; Tara J. Cepon-Robins; Theresa E. Gildner; Urlacher, Samuel S.; Bohannan, Brendan J.M.; Snodgrass, J. Josh; Lawrence S. Sugiyama

    2014-01-01

    Cassava beer, or chicha, is typically consumed daily by the indigenous Shuar people of the Ecuadorian Amazon. This traditional beverage made from cassava tuber (Manihot esculenta) is thought to improve nutritional quality and flavor while extending shelf life in a tropical climate. Bacteria responsible for chicha fermentation could be a source of microbes for the human microbiome, but little is known regarding the microbiology of chicha. We investigated bacterial community composition of chic...

  13. Production and transformation of dissolved neutral sugars and amino acids by bacteria in seawater

    Jørgensen, Linda; Lechtenfeld, O.J.; Benner, R.; Middelboe, M.; Stedmon, Colin

    2014-01-01

    production and degradation processes. This study provides insight into the bioavailability of biomolecules as well as the chemical composition of DOM produced by bacteria. The molecular compositions of combined neutral sugars and amino acids were investigated in DOM produced by bacteria and in DOM remaining...... degradation are not strongly influenced by the initial substrate or bacterial community. The molecular composition of neutral sugars released by bacteria was characterized by a high glucose content (47 mol %) and heterogeneous contributions from other neutral sugars (3–14 mol %). DOM remaining after bacterial...... acid, glutamic acid, serine and alanine reached around 0.79, 0.32, 0.30 and 0.51 in all treatments, respectively. The striking similarity in neutral sugar and amino acid compositions between natural (representing marine semi-labile and refractory DOM) and artificial (representing bacterially produced...

  14. Molecular Identification of Lactic Acid Bacteria Producing Antimicrobial Agents from Bakasang, An Indonesian Traditional Fermented Fish Product

    Helen Joan Lawalata; Langkah Sembiring; Endang Sutriswati Rahayu

    2015-01-01

    AbstractTwenty seven strains of lactic acid bacteria (LAB) were isolated from bakasang, Indonesian traditional fermented fish product. In general, LAB have inhibitory activity againts pathogenic bacteria and spoilage bacteria. Screening for antimicrobia activity of isolates were performed with well-diffusion method. One isolate that was designed as Pediococcus BksC24 was the strongest against bacteria pathogenic and spoilage bacteria. This strain was further identified by 16S rRNA gen sequenc...

  15. Bioprocessing with enzymes and lactic acid bacteria for production of new functional faba bean ingredients

    Karsma, Anni

    2015-01-01

    Faba bean (Vicia Faba L.) is a nutritious high protein crop widely cultivated for uses of both food and feed. Its use has limited due to presence of anti-nutritional factors, including phytic acid, bitter taste and poor technological functionality. Phytic acid is the major storage of phosphorus in cereals and legumes lowering the bioavailability of proteins and micronutrients. The aim of this master’s thesis was to study the impacts of bioprocessing with enzymes and lactic acid bacteria on bo...

  16. Repetitive sequence based polymerase chain reaction to differentiate close bacteria strains in acidic sites

    XIE Ming; YIN Hua-qun; LIU Yi; LIU Jie; LIU Xue-duan

    2008-01-01

    To study the diversity of bacteria strains newly isolated from several acid mine drainage(AMD) sites in China,repetitive sequence based polymerase chain reaction (rep-PCR),a well established technology for diversity analysis of closely related bacteria strains,was conducted on 30 strains of bacteria Leptospirillum ferriphilium,8 strains of bacteria Acidithiobacillus ferrooxidans,as well as the Acidithiobacillus ferrooxidans type strain ATCC (American Type Culture Collection) 23270.The results showed that,using ERIC and BOX primer sets,rep-PCR produced highly discriminatory banding patterns.Phylogenetic analysis based on ERIC-PCR banding types was made and the results indicated that rep-PCR could be used as a rapid and highly discriminatory screening technique in studying bacterial diversity,especially in differentiating bacteria within one species in AMD.

  17. HYDROLYTIC BREAKDOWN OF LACTOFERRICIN BY LACTIC ACID BACTERIA

    Lactoferricin is a 25 amino acid antimicrobial peptide domain that is liberated by pepsin digestion of lactoferrin in bovine milk. Along with its antibacterial properties, lactoferricin has also been reported to have immunostimulatory, antiviral, and anticarcinogenic effects. There is substantial ...

  18. Occurrence of Lactic Acid Bacteria During the Different Stages of Vinification and Conservation of Wines

    Lafon-Lafourcade, S.; Carre, E.; Ribéreau-Gayon, P.

    1983-01-01

    We showed that the growth of lactic acid bacteria during alcoholic fermentation depends on the composition of the must. We illustrated how the addition of sulfur dioxide to the must before fermentation and the temperature of storage both affect the growth of these bacteria in the wine. Whereas species of Lactobacillus and Leuconostoc mesenteroides were isolated from grapes and must, Leuconostoc oenos was the only species isolated after alcoholic fermentation. This organism was responsible for...

  19. Biotechnology and pasta-making: Lactic Acid Bacteria as a new driver of innovation

    GiuseppeSpano; VittorioCapozzi; DanielaFiocco; MariagiovannaFragasso

    2012-01-01

    Cereals-derived foods represent a key constituent in the diet of many populations. In particular, pasta is consumed in large quantities throughout the world in reason of its nutritive importance, containing significant amounts of complex carbohydrates, proteins, B-vitamins, and iron. Lactic acid bacteria (LAB) are a heterogeneous group of bacteria that play a key role in the production of fermented foods and beverages with high relevance for human and animal health. A wide literature testifie...

  20. Biotechnology and Pasta-Making: Lactic Acid Bacteria as a New Driver of Innovation

    Capozzi, Vittorio; Russo, Pasquale; Fragasso, Mariagiovanna; de Vita, Pasquale; Fiocco, Daniela; Spano, Giuseppe

    2012-01-01

    Cereals-derived foods represent a key constituent in the diet of many populations. In particular, pasta is consumed in large quantities throughout the world in reason of its nutritive importance, containing significant amounts of complex carbohydrates, proteins, B-vitamins, and iron. Lactic acid bacteria (LAB) are a heterogeneous group of bacteria that play a key role in the production of fermented foods and beverages with high relevance for human and animal health. A wide literature testifie...

  1. Lactic acid bacteria from Jijel's traditional butter: Isolation, identification and major technological traits

    Idoui, Tayeb; Karam, Nour-Eddine

    2008-01-01

    Twenty seven (27) lactic acid bacteria were isolated from Jijel’s traditional butter. These strains belong to three genera: Lactococcus, Lactobacillus and Leuconostoc. The results showed that Lactobacillus plantarum was the predominant species in this traditional butter. It appears that these strains have some interesting technological properties.Se aíslan veintisiete (27) bacterias acidolácticas de la mantequilla tradicional de Jijel. Éstas pertenecen a los géneros Lactococcus, Lactobacill...

  2. Bacteriophages of lactic acid bacteria and their impact on milk fermentations

    Garneau, Josiane E.; Moineau, Sylvain

    2011-01-01

    Every biotechnology process that relies on the use of bacteria to make a product or to overproduce a molecule may, at some time, struggle with the presence of virulent phages. For example, phages are the primary cause of fermentation failure in the milk transformation industry. This review focuses on the recent scientific advances in the field of lactic acid bacteria phage research. Three specific topics, namely, the sources of contamination, the detection methods and the control procedures w...

  3. Bio-detoxification of mycotoxins by lactic acid bacteria from different food matrices

    Inês, António; Guimarães, Ana; Maria, J. C.; Laranjo,V.; Venâncio, Armando; Abrunhosa, Luís

    2015-01-01

    Lactic acid bacteria (LAB) play a key role in the biopreservation of a wide range of fermented food products, such as yogurt, cheese, fermented milks, meat, fish, vegetables (sauerkraut, olives and pickles), certain beer brands, wines and silage, allowing their safe consumption, which gave to these bacteria a GRAS (Generally Recognised as Safe) status. Besides that, the use of LAB in food and feed is a promising strategy to reduce the exposure to dietary mycotoxins, improving their ...

  4. Influence of aeration intensity and medium acidity on phosphate mobilization affected by soil bacteria

    K. V. Lavrentyeva; P. I. Kharchenko; N. V. Cherevach; A. I. Vinnikov

    2009-01-01

    The paper deals with the investigation of phosphate solubilisation conducted by two bacteria Pseudomonas putida and Enterobacter dissolvens under conditions of different rates of aeration and рН. Bacterial development was characterized by different media acidity and aeration levels. It was established optimal aeration rates and potential of hydrogen for soil bacteria growth and phosphate solubilisation – 0.5721 mole О2/l per hour and pH ≈ 6.0.

  5. Lactic acid bacteria: reviewing the potential of a promising delivery live vector for biomedical purposes

    Cano-Garrido, Olivia; Seras-Franzoso, Joaquin; Garcia-Fruitós, Elena

    2015-01-01

    Lactic acid bacteria (LAB) have a long history of safe exploitation by humans, being used for centuries in food production and preservation and as probiotic agents to promote human health. Interestingly, some species of these Gram-positive bacteria, which are generally recognized as safe organisms by the US Food and Drug Administration (FDA), are able to survive through the gastrointestinal tract (GIT), being capable to reach and colonize the intestine, where they play an important role. Besi...

  6. Lactic acid bacteria and their antimicrobial peptides : Induction,detection,partial characterization, and potential applications

    Abbas Hilmi, Hanan

    2010-01-01

    Bacteriocin-producing lactic acid bacteria and their isolated peptide bacteriocins are of value to control pathogens and spoiling microorganisms in foods and feed. Nisin is the only bacteriocin that is commonly accepted as a food preservative and has a broad spectrum of activity against Gram-positive organisms including spore forming bacteria. In this study nisin induction was studied from two perspectives, induction from inside of the cell and selection of nisin inducible strains with increa...

  7. Mechanical and acid neutralizing properties and bacteria inhibition of amorphous calcium phosphate dental nanocomposite

    Moreau, Jennifer L.; Sun, Limin; Chow, Laurence C.; Xu, Hockin H. K.

    2011-01-01

    Dental composites do not hinder bacteria colonization and plaque formation. Caries at the restoration margins is a frequent reason for replacement of existing restorations, which accounts for 50 to 70% of all restorations. The objectives of this study were to examine the filler level effect on nanocomposite containing nanoparticles of amorphous calcium phosphate (NACP) and investigate the load-bearing and acid-neutralizing properties and bacteria inhibition. NACP with 116-nm particle size wer...

  8. The evolution of lactic acid bacteria community during the development of mature sourdough

    Savić Dragiša S.; Joković Nataša M.; Žugić-Petrović Tanja D.

    2009-01-01

    In order to follow the composition and changes in lactic acid bacteria (LAB) population of rye flour sourdough that was continuously propagated by a repeated inoculation, sixty-two strains of LAB were isolated and characterized. The LAB were the only bacteria detected, both at the end of the second propagation step and in the stage of mature sourdough (after two weeks of continuous daily refreshment). The stable ecological system in rye sourdough could be established from the second propagati...

  9. Relevance and application of sortase and sortase-dependent proteins in lactic acid bacteria

    ToddKlaenhammer

    2013-01-01

    Lactic acid bacteria (LAB) are a diverse group of Gram-positive bacteria found in a vast array of environments including dairy products and the human gastrointestinal tract. In both niches, surface proteins play a crucial role in mediating interactions with the surrounding environment. The sortase enzyme is responsible for covalently coupling a subset of surface dependent proteins (SDPs) to the cell wall of Gram-positive organisms through recognition of a conserved C-terminal LPXTG motif. Ge...

  10. Application of molecular techniques for identification and ennumeration of acetic acid bacteria

    González Benito, Angel

    2005-01-01

    Application of molecular techniques for identification and enumeration of acetic acid bacteria:Los principales objetivos de la tesis son el desarrollo de técnicas de biología molecular rápidas y fiables para caracterizar bacterias acéticas.Las bacterias acéticas son las principales responsables del picado de los vinos y de la producción de vinagre. Sin embargo, existe un desconocimiento importante sobre su comportamiento y evolución. Las técnicas de enumeración y de identificación basadas en ...

  11. Role in Cheese Flavour Formation of Heterofermentative Lactic Acid Bacteria from Mesophilic Starter Cultures

    Pedersen, Thomas Bæk

    Undefined mesophilic cheese starters are complex ecosystems that contain both homofermentative and heterofermentative lactic acid bacteria, with the Lactococcus genera representing the former and Lceuonostoc and sometimes Lactobacillus the latter. These starters originate from old butter starters...... dairy strains had, in comparison with plant isolates, the ability to ferment citrate and lacked several genes involved in the fermentation of complex carbohydrates. The presented research in this thesis has gained insight in to the role of heterofermentative lactic acid bacteria in cheese flavour...... formation. The traditional DL-starters contained numerous of strains of heterofermentative Le. mesenteroides, whereas Le. pseudomesenteroides and  only were found in some starters. The potential of heterofermentative lactic acid bacteria to effect the flavour formation in cheese seems to be dependent on how...

  12. Phenotypic and genotypic characterization of lactic acid bacteria isolated from raw goat milk and effect of farming practices on the dominant species of lactic acid bacteria.

    Tormo, Hélène; Ali Haimoud Lekhal, Djamila; Roques, C

    2015-10-01

    Lactic acid bacteria, in particular Lactococcus lactis, play a decisive role in the cheese making process and more particularly in lactic cheeses which are primarily produced on goat dairy farms. The objective of this study was therefore to identify the main lactic acid bacteria found in raw goats' milk from three different regions in France and evaluate if certain farming practices have an effect on the distribution of species of lactic acid bacteria in the various milk samples. Identification at genus or species level was carried out using phenotypic tests and genotypic methods including repetitive element REP-PCR, species-specific PCR and 16S rRNA gene sequencing. The distribution of the main bacterial species in the milk samples varied depending on farms and their characteristics. Out of the 146 strains identified, L. lactis was the dominant species (60% of strains), followed by Enterococcus (38%) of which Enterococcus faecalis and Enterococcus faecium. Within the species L. lactis, L. lactis subsp lactis was detected more frequently than L. lactis subsp cremoris (74% vs. 26%). The predominance of L. lactis subsp cremoris was linked to geographical area studied. It appears that the animals' environment plays a role in the balance between the dominance of L. lactis and enterococci in raw goats' milk. The separation between the milking parlor and the goat shed (vs no separation) and only straw in the bedding (vs straw and hay) seems to promote L. lactis in the milk (vs enterococci). PMID:26082325

  13. [Comparative genomics and evolutionary analysis of CRISPR loci in acetic acid bacteria].

    Kai, Xia; Xinle, Liang; Yudong, Li

    2015-12-01

    The clustered regularly interspaced short palindromic repeat (CRISPR) is a widespread adaptive immunity system that exists in most archaea and many bacteria against foreign DNA, such as phages, viruses and plasmids. In general, CRISPR system consists of direct repeat, leader, spacer and CRISPR-associated sequences. Acetic acid bacteria (AAB) play an important role in industrial fermentation of vinegar and bioelectrochemistry. To investigate the polymorphism and evolution pattern of CRISPR loci in acetic acid bacteria, bioinformatic analyses were performed on 48 species from three main genera (Acetobacter, Gluconacetobacter and Gluconobacter) with whole genome sequences available from the NCBI database. The results showed that the CRISPR system existed in 32 species of the 48 strains studied. Most of the CRISPR-Cas system in AAB belonged to type I CRISPR-Cas system (subtype E and C), but type II CRISPR-Cas system which contain cas9 gene was only found in the genus Acetobacter and Gluconacetobacter. The repeat sequences of some CRISPR were highly conserved among species from different genera, and the leader sequences of some CRISPR possessed conservative motif, which was associated with regulated promoters. Moreover, phylogenetic analysis of cas1 demonstrated that they were suitable for classification of species. The conservation of cas1 genes was associated with that of repeat sequences among different strains, suggesting they were subjected to similar functional constraints. Moreover, the number of spacer was positively correlated with the number of prophages and insertion sequences, indicating the acetic acid bacteria were continually invaded by new foreign DNA. The comparative analysis of CRISR loci in acetic acid bacteria provided the basis for investigating the molecular mechanism of different acetic acid tolerance and genome stability in acetic acid bacteria. PMID:26704949

  14. 10-oxo-12(Z)-octadecenoic acid, a linoleic acid metabolite produced by gut lactic acid bacteria, potently activates PPARγ and stimulates adipogenesis

    Goto, Tsuyoshi, E-mail: tgoto@kais.kyoto-u.ac.jp [Laboratory of Molecular Function of Food, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji 611-0011 (Japan); Research Unit for Physiological Chemistry, The Center for the Promotion of Interdisciplinary Education and Research, Kyoto University (Japan); Kim, Young-Il; Furuzono, Tomoya [Laboratory of Molecular Function of Food, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji 611-0011 (Japan); Takahashi, Nobuyuki [Laboratory of Molecular Function of Food, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji 611-0011 (Japan); Research Unit for Physiological Chemistry, The Center for the Promotion of Interdisciplinary Education and Research, Kyoto University (Japan); Yamakuni, Kanae; Yang, Ha-Eun; Li, Yongjia [Laboratory of Molecular Function of Food, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji 611-0011 (Japan); Ohue, Ryuji [Laboratory of Molecular Function of Food, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji 611-0011 (Japan); Research Unit for Physiological Chemistry, The Center for the Promotion of Interdisciplinary Education and Research, Kyoto University (Japan); Nomura, Wataru [Laboratory of Molecular Function of Food, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji 611-0011 (Japan); Sugawara, Tatsuya [Laboratory of Marine Bioproducts Technology, Division of Applied Biosciences, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502 (Japan); Yu, Rina [Department of Food Science and Nutrition, University of Ulsan, Ulsan 680-749 (Korea, Republic of); Kitamura, Nahoko [Laboratory of Fermentation Physiology and Applied Microbiology, Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502 (Japan); and others

    2015-04-17

    Our previous study has shown that gut lactic acid bacteria generate various kinds of fatty acids from polyunsaturated fatty acids such as linoleic acid (LA). In this study, we investigated the effects of LA and LA-derived fatty acids on the activation of peroxisome proliferator-activated receptors (PPARs) which regulate whole-body energy metabolism. None of the fatty acids activated PPARδ, whereas almost all activated PPARα in luciferase assays. Two fatty acids potently activated PPARγ, a master regulator of adipocyte differentiation, with 10-oxo-12(Z)-octadecenoic acid (KetoA) having the most potency. In 3T3-L1 cells, KetoA induced adipocyte differentiation via the activation of PPARγ, and increased adiponectin production and insulin-stimulated glucose uptake. These findings suggest that fatty acids, including KetoA, generated in gut by lactic acid bacteria may be involved in the regulation of host energy metabolism. - Highlights: • Most LA-derived fatty acids from gut lactic acid bacteria potently activated PPARα. • Among tested fatty acids, KetoA and KetoC significantly activated PPARγ. • KetoA induced adipocyte differentiation via the activation of PPARγ. • KetoA enhanced adiponectin production and glucose uptake during adipogenesis.

  15. 10-oxo-12(Z)-octadecenoic acid, a linoleic acid metabolite produced by gut lactic acid bacteria, potently activates PPARγ and stimulates adipogenesis

    Our previous study has shown that gut lactic acid bacteria generate various kinds of fatty acids from polyunsaturated fatty acids such as linoleic acid (LA). In this study, we investigated the effects of LA and LA-derived fatty acids on the activation of peroxisome proliferator-activated receptors (PPARs) which regulate whole-body energy metabolism. None of the fatty acids activated PPARδ, whereas almost all activated PPARα in luciferase assays. Two fatty acids potently activated PPARγ, a master regulator of adipocyte differentiation, with 10-oxo-12(Z)-octadecenoic acid (KetoA) having the most potency. In 3T3-L1 cells, KetoA induced adipocyte differentiation via the activation of PPARγ, and increased adiponectin production and insulin-stimulated glucose uptake. These findings suggest that fatty acids, including KetoA, generated in gut by lactic acid bacteria may be involved in the regulation of host energy metabolism. - Highlights: • Most LA-derived fatty acids from gut lactic acid bacteria potently activated PPARα. • Among tested fatty acids, KetoA and KetoC significantly activated PPARγ. • KetoA induced adipocyte differentiation via the activation of PPARγ. • KetoA enhanced adiponectin production and glucose uptake during adipogenesis

  16. Bile Salt and Acid Tolerant of Lactic Acid Bacteria Isolated from Proventriculus of Broiler Chicken

    E. Damayanti

    2014-08-01

    Full Text Available The aim of this research was to obtain the lactic acid bacteria (LAB as probiotic candidates which have resistance to bile salt and acid condition. LAB was obtained using isolation method from proventriculus of broiler chicken. Selective MRS media with 0.2% CaCO3 addition were used for LAB isolation using pour plate sampling method under anaerobic condition. The result showed that four selected isolates had morphological and biochemical characteristics as LAB. The selected LAB was characterized as follow: antibacterial activities, antibiotic sensitivity, resistance on bile salt, gastric juice and acid condition, and biochemical identification. Antibacterial activities assay of cell free supernatant was confirmed using disc paper diffusion method which was arranged on factorial design and each treatment consisted of three replications. The cell free supernatant of LAB isolates had antibacterial activities against Escherichia coli, Pseudomonas aerugenosa, and Salmonella pullorum. Molecular identification procedure using 16S rRNA sequence analysis showed that R01 and R02 as Pediococcus acidilactici. The viability of the two isolates were tested by acid pH (pH 1, 2, and 3, gastric juice pH 2, and bile salt condition for digestives tract simulation. The result showed that R01 and R02 had a high viability percentages at pH 1, 2, and 3 (95.45%, 99.49%, 104.01%, and 67.17%, 120.74%, 103.4%, respectively and at bile salt simulation for 1-2 hours (100.35%-102.71% and 100.02%-102.65%, respectively, but at gastric juice simulation for 1-2 hours, the P. acidilactici R01 had higher viability than P. acidilactici R02 (59.69%-76.53% versus 43.57%-40.69%, respectively. In the antibiotic sensitivity test for three antibiotics (i.e. erythromicin 15 µg, penicillin G 10 µg, and streptomycin 10 µg, the P. acidilactici R02 showed resistance to Streptomycin and Penicillin. It is concluded that P. acidilactici R01 and P. acidilactici R02 isolated from proventriculus

  17. TO THE QUESTION OF BIOSYNTHESIS OF CROTONALDEHYDE OF WINE YEAST AND LACTIC ACID BACTERIA DURING VINIFICATION

    Kushnereva E. V.

    2014-01-01

    Full Text Available The article investigates the possible pathways for the formation of crotonaldehyde in wine production in the result of the activity of wine yeast and lactic acid bacteria. It established that exposure to exhaust gases, noble rot, pathogens and pests on grape plant does not lead to the biosynthesis of crotonaldehyde in grape berry. The experimental data to identify probable pathways for the formation of crotonaldehyde during vinification has been presented. The effect of the test substance on the life of yeasts and lactic acid bacteria has been estimated

  18. Plasmids from Food Lactic Acid Bacteria: Diversity, Similarity, and New Developments

    Yanhua Cui

    2015-06-01

    Full Text Available Plasmids are widely distributed in different sources of lactic acid bacteria (LAB as self-replicating extrachromosomal genetic materials, and have received considerable attention due to their close relationship with many important functions as well as some industrially relevant characteristics of the LAB species. They are interesting with regard to the development of food-grade cloning vectors. This review summarizes new developments in the area of lactic acid bacteria plasmids and aims to provide up to date information that can be used in related future research.

  19. Effect of proteolitic enzymes with probiotic of lactic acid bacteria on characteristics of cow milk dadih

    Miskiyah; S. Usmiati; Mulyorini

    2011-01-01

    Texture of dadih from cow milk tends to be soft, while dadih from buffalo milk have more compact and solid texture. Enzyme is one of food additives that may produce fermented products made from cow milk that has same charcteristic as dadih’s from buffalo milk. Lactic acid bacteria in fermented milk affect product characteristics. This study aimed to determine the effect of combination of enzyme and probiotic lactic acid bacteria on the characteristics of cow's milk dadih. The study was aime d...

  20. Development of a Method for Detection of Lactic Acid Bacteria Producing Exclusively the l-(+)- Isomer of Lactic Acid

    Jehanno, D.; Thuault, D; Bourgeois, C. M.

    1992-01-01

    A method was developed for the detection and isolation, within a population of lactic acid bacteria, of strains producing exclusively the l-(+)- isomer of lactic acid; the visual detection of colonies of these particular strains can be carried out directly on agar plates (50 to 70 colonies per plate). The method is based on an enzymatic stereospecific reaction involving d-(−)-lactate dehydrogenase and linked to a staining reaction; the diffusion area of the d-(−)- isomer stains red around the...

  1. Lactic Acid Bateria - Friend or Foe? Lactic Acid Bacteria in the Production of Polysaccharides and Fuel Ethanol

    Lactic acid bacteria (LAB) have been widely used in the production of fermented foods and as probiotics. Alternan is a glucan with a distinctive backbone structure of alternating alpha-(1,6) and alpha-(1,3) linkages produced by the LAB Leuconostoc mesenteroides. In recent years, improved strains f...

  2. Phenolic content, antioxidant activities and stimulatory roles of citrus fruits on some lactic acid bacteria

    Irkin Reyhan

    2015-01-01

    Full Text Available In this study, phenolic compounds and antioxidant activities in citrus fruits and their peels were determined, and their stimulatory roles on some lactic acid bacteria were investigated. Phenolic compounds in citrus fruits such as mandarin, lemon, orange and grapefruit were determined either in the juices or in the peel extracts. Total phenolic content was determined in a spectrophotometer at 685 nm using the adapted Folin-Ciocalteu method. Total flavonoid content was measured using LC/MS (liquid chromatography-mass spectrometry. The effects of the fruit juices and peel extracts on the selected lactic acid bacteria (Lactobacillus delbrueckii NRRL B5448, Lb. casei NRRL B1922, Lb. acidophilus NRRL B4495 were investigated. The tested lactic acid bacteria were significantly affected by chlorogenic acid, hesperidin, naringin and caffeic acid compared to the control samples (P≤0.05. Antioxidant properties of fruit samples were also measured using the DPPH (2,2-diphenyl-1-picrylhydrazyl method. The phenolics positively affected the metabolism of bacteria, with the stimulatory effects of the assayed samples being influenced by the phenolic profile.

  3. PENAMBAHAN BAKTERI ASAM LAKTAT TERENKAPSULASI UNTUK MENEKAN PERTUMBUHAN BAKTERI PATOGEN PADA PROSES PRODUKSI TAPIOKA [Addition of Encapsulated Lactic Acid Bacteria to Suppress the Growth of Pathogenic Bacteria during Tapioca Production

    Glisina Dwinoor Rembulan; Titi Candra Sunarti; Anja Meryandini

    2015-01-01

    Lactic acid bacteria (LAB) produce organic acids and active compounds which can inhibit the growth of pathogenic bacteria. Lactic acid bacteria potentially can be introduced to inhibit pathogenic bacteria in the tapioca production at the extraction stage, especially during the settling process since there is possibility of starch slurry to be contaminated by pathogenic bacteria from water. The objectives of this research were to design a solid starter of LAB through encapsulation by using mod...

  4. Addicting diverse bacteria to a noncanonical amino acid.

    Tack, Drew S; Ellefson, Jared W; Thyer, Ross; Wang, Bo; Gollihar, Jimmy; Forster, Matthew T; Ellington, Andrew D

    2016-03-01

    Engineered orthogonal translation systems have greatly enabled the expansion of the genetic code using noncanonical amino acids (NCAAs). However, the impact of NCAAs on organismal evolution remains unclear, in part because it is difficult to force the adoption of new genetic codes in organisms. By reengineering TEM-1 β-lactamase to be dependent on a NCAA, we maintained bacterial NCAA dependence for hundreds of generations without escape. PMID:26780407

  5. Acid production in dental plaque after exposure to probiotic bacteria

    Keller Mette K; Twetman Svante

    2012-01-01

    Abstract Background The increasing interest in probiotic lactobacilli in health maintenance has raised the question of potential risks. One possible side effect could be an increased acidogenicity in dental plaque. The aim of this study was to investigate the effect of probiotic lactobacilli on plaque lactic acid (LA) production in vitro and in vivo. Methods In the first part (A), suspensions of two lactobacilli strains (L. reuteri DSM 17938, L. plantarum 299v) were added to suspensions of su...

  6. Local domestication of lactic acid bacteria via cassava beer fermentation.

    Colehour, Alese M; Meadow, James F; Liebert, Melissa A; Cepon-Robins, Tara J; Gildner, Theresa E; Urlacher, Samuel S; Bohannan, Brendan J M; Snodgrass, J Josh; Sugiyama, Lawrence S

    2014-01-01

    Cassava beer, or chicha, is typically consumed daily by the indigenous Shuar people of the Ecuadorian Amazon. This traditional beverage made from cassava tuber (Manihot esculenta) is thought to improve nutritional quality and flavor while extending shelf life in a tropical climate. Bacteria responsible for chicha fermentation could be a source of microbes for the human microbiome, but little is known regarding the microbiology of chicha. We investigated bacterial community composition of chicha batches using Illumina high-throughput sequencing. Fermented chicha samples were collected from seven Shuar households in two neighboring villages in the Morona-Santiago region of Ecuador, and the composition of the bacterial communities within each chicha sample was determined by sequencing a region of the 16S ribosomal gene. Members of the genus Lactobacillus dominated all samples. Significantly greater phylogenetic similarity was observed among chicha samples taken within a village than those from different villages. Community composition varied among chicha samples, even those separated by short geographic distances, suggesting that ecological and/or evolutionary processes, including human-mediated factors, may be responsible for creating locally distinct ferments. Our results add to evidence from other fermentation systems suggesting that traditional fermentation may be a form of domestication, providing endemic beneficial inocula for consumers, but additional research is needed to identify the mechanisms and extent of microbial dispersal. PMID:25071997

  7. Local domestication of lactic acid bacteria via cassava beer fermentation

    Alese M. Colehour

    2014-07-01

    Full Text Available Cassava beer, or chicha, is typically consumed daily by the indigenous Shuar people of the Ecuadorian Amazon. This traditional beverage made from cassava tuber (Manihot esculenta is thought to improve nutritional quality and flavor while extending shelf life in a tropical climate. Bacteria responsible for chicha fermentation could be a source of microbes for the human microbiome, but little is known regarding the microbiology of chicha. We investigated bacterial community composition of chicha batches using Illumina high-throughput sequencing. Fermented chicha samples were collected from seven Shuar households in two neighboring villages in the Morona-Santiago region of Ecuador, and the composition of the bacterial communities within each chicha sample was determined by sequencing a region of the 16S ribosomal gene. Members of the genus Lactobacillus dominated all samples. Significantly greater phylogenetic similarity was observed among chicha samples taken within a village than those from different villages. Community composition varied among chicha samples, even those separated by short geographic distances, suggesting that ecological and/or evolutionary processes, including human-mediated factors, may be responsible for creating locally distinct ferments. Our results add to evidence from other fermentation systems suggesting that traditional fermentation may be a form of domestication, providing endemic beneficial inocula for consumers, but additional research is needed to identify the mechanisms and extent of microbial dispersal.

  8. Naturally fermented Jijelian black olives: microbiological characteristics and isolation of lactic acid bacteria

    Karam, Nour-Eddine

    2009-12-01

    Full Text Available A study of the microflora of traditionally fermented black olives in Eastern Algeria is presented. A count of the following microbial groups was carried out: mesophilic bacteria, enterobacteria, lactic acid bacteria (LAB, staphylococci and yeast. In a second phase, the identification and assessment of the technological traits of LAB was performed. Seventeen lactic acid bacteria were isolated and identified. These isolates were represented by two genera: Lactobacillus and Leuconostoc. The results showed that Lactobacillus plantarum was the predominant species in this traditional product.Un estudio sobre la microflora de aceitunas negras fermentada por métodos tradicionales en el Este de Argelia es presentado. Se realizo el siguiente recuento de grupos de microorganismos: bacterias mesófilas, enterobacterias, bacterias ácido lácticas (LAB, staphylococcus y levaduras. En una segunda fase, la identificación y evaluación de aspectos tecnológicos de LAB fue realizada. Setenta bacterias ácido lácticas fueron aisladas e identificadas. Estos aislados contenían principalmente dos géneros: Lactobacillus y Leuconostoc. Los resultados mostraron que Lactobacillus plantarum fue la especie predominante en este producto tradicional.

  9. Lactic acid bacteria in dairy food: surface characterization and interactions with food matrix components.

    Burgain, J; Scher, J; Francius, G; Borges, F; Corgneau, M; Revol-Junelles, A M; Cailliez-Grimal, C; Gaiani, C

    2014-11-01

    This review gives an overview of the importance of interactions occurring in dairy matrices between Lactic Acid Bacteria and milk components. Dairy products are important sources of biological active compounds of particular relevance to human health. These compounds include immunoglobulins, whey proteins and peptides, polar lipids, and lactic acid bacteria including probiotics. A better understanding of interactions between bioactive components and their delivery matrix may successfully improve their transport to their target site of action. Pioneering research on probiotic lactic acid bacteria has mainly focused on their host effects. However, very little is known about their interaction with dairy ingredients. Such knowledge could contribute to designing new and more efficient dairy food, and to better understand relationships between milk constituents. The purpose of this review is first to provide an overview of the current knowledge about the biomolecules produced on bacterial surface and the composition of the dairy matter. In order to understand how bacteria interact with dairy molecules, adhesion mechanisms are subsequently reviewed with a special focus on the environmental conditions affecting bacterial adhesion. Methods dedicated to investigate the bacterial surface and to decipher interactions between bacteria and abiotic dairy components are also detailed. Finally, relevant industrial implications of these interactions are presented and discussed. PMID:25277266

  10. Heterologous surface display on lactic acid bacteria: non-GMO alternative?

    Zadravec, Petra; Štrukelj, Borut; Berlec, Aleš

    2015-01-01

    Lactic acid bacteria (LAB) are food-grade hosts for surface display with potential applications in food and therapy. Alternative approaches to surface display on LAB would avoid the use of recombinant DNA technology and genetically-modified organism (GMO)-related regulatory requirements. Non-covalent surface display of proteins can be achieved by fusing them to various cell-wall binding domains, of which the Lysine motif domain (LysM) is particularly well studied. Fusion proteins have been isolated from recombinant bacteria or from their growth medium and displayed on unmodified bacteria, enabling heterologous surface display. This was demonstrated on non-viable cells devoid of protein content, termed bacteria-like particles, and on various species of genus Lactobacillus. Of the latter, Lactobacillus salivarius ATCC 11741 was recently shown to be particularly amenable for LysM-mediated display. Possible regulatory implications of heterologous surface display are discussed, particularly those relevant for the European Union. PMID:25880164

  11. Acid production in dental plaque after exposure to probiotic bacteria

    Keller Mette K

    2012-10-01

    Full Text Available Abstract Background The increasing interest in probiotic lactobacilli in health maintenance has raised the question of potential risks. One possible side effect could be an increased acidogenicity in dental plaque. The aim of this study was to investigate the effect of probiotic lactobacilli on plaque lactic acid (LA production in vitro and in vivo. Methods In the first part (A, suspensions of two lactobacilli strains (L. reuteri DSM 17938, L. plantarum 299v were added to suspensions of supragingival dental plaque collected from healthy young adults (n=25. LA production after fermentation with either xylitol or fructose was analyzed. In the second part (B, subjects (n=18 were given lozenges with probiotic lactobacilli (L. reuteri DSM 17938 and ATCC PTA 5289 or placebo for two weeks in a double-blinded, randomized cross-over trial. The concentration of LA in supragingival plaque samples was determined at baseline and after 2 weeks. Salivary counts of mutans streptococci (MS and lactobacilli were estimated with chair-side methods. Results Plaque suspensions with L. reuteri DSM 17938 produced significantly less LA compared with L. plantarum 299v or controls (p Conclusion Lactic acid production in suspensions of plaque and probiotic lactobacilli was strain-dependant and the present study provides no evidence of an increase in plaque acidity by the supply of selected probiotic lactobacilli when challenged by fructose or xylitol. The study protocol was approved by The Danish National Committee on Biomedical Research Ethics (protocol no H-2-2010-112. Trial registration NCT01700712

  12. Cholesterol Assimilation by Lactic Acid Bacteria and Bifidobacteria Isolated from the Human Gut

    Dora I A Pereira; Gibson, Glenn R.

    2002-01-01

    The objective of this study was to evaluate the effect of human gut-derived lactic acid bacteria and bifidobacteria on cholesterol levels in vitro. Continuous cultures inoculated with fecal material from healthy human volunteers with media supplemented with cholesterol and bile acids were used to enrich for potential cholesterol assimilators among the indigenous bacterial populations. Seven potential probiotics were found: Lactobacillus fermentum strains F53 and KC5b, Bifidobacterium infantis...

  13. Evaluation of Immunomodulatory Effects of Lactic Acid Bacteria in Turbot (Scophthalmus maximus)

    Villamil, L.; Tafalla, C.; Figueras, A.; Novoa, B.

    2002-01-01

    In the present work, the effects of several lactic acid bacteria on the immune response of turbot (Scophthalmus maximus) macrophages have been studied both in vitro and in vivo. Out of six lactic acid bacterial strains tested, only heat-killed Lactococcus lactis significantly increased the turbot head kidney macrophage chemiluminescent (CL) response after 24 h of incubation. Nitric oxide (NO) was also significantly enhanced by this bacterium after 72 h of incubation with either viable (103 an...

  14. Lactic acid bacteria in Hamei and Marcha of North East India

    Tamang, J. P.; Dewan, S.; Tamang, B.; Rai, A; Schillinger, U.; Holzapfel, W. H.

    2007-01-01

    Hamei and Marcha are mixed dough inocula used as starters for preparation of various indigenous alcoholic beverages in Manipur and Sikkim in India, respectively. These starters are traditionally prepared from rice with wild herbs and spices. Samples of Hamei and Marcha, collected from Manipur and Sikkim, respectively, were analysed for lactic acid bacterial composition. The population of lactic acid bacteria (LAB) was 6.9 and 7.1 Log cfu/g in Hamei and Marcha, respectively. On the basis of ph...

  15. Selection of potential probiotic lactic acid bacteria from fermented olives by in vitro tests

    Argyri, Anthoula; Zoumpopoulou, Georgia; Karatzas, Kimon Andreas; Tsakalidou, Effie; Nychas, George John; Panagou, Efstathios; Tassou, Chrysoula

    2012-01-01

    The present study aims to evaluate the probiotic potential of lactic acid bacteria (LAB) isolated from naturally fermented olives and select candidates to be used as probiotic starters for the improvement of the traditional fermentation process and the production of newly added value functional foods. Seventy one (71) lactic acid bacterial strains (17 Leuconostoc mesenteroides, 1 Ln. pseudomesenteroides, 13 Lactobacillus plantarum, 37 Lb. pentosus, 1 Lb. paraplantarum, and 2 Lb. paracasei sub...

  16. Selection of exopolysaccharide-producing lactic acid bacteria isolates from Inner Mongolian traditional yoghurt

    Zhang Chun-lei; Li Jia-qi; Guo Hai-tao; Wang Jie; Xu Ri-hua

    2014-01-01

    Lactic acid bacteria (LAB) isolated from Inner Mongolian traditional yoghurt were evaluated for the production of exopolysaccharides (EPS) by phenol-sulphuric acid method after ethanol precipitation and dialysis. Total polysaccharide was extracted from sucrose-containing MRS broth cultures of the selected LAB strains. Comparison of the EPS yields revealed that among tested LAB, strain 37 exhibited the highest production of 536.904 mg/L. The strain was identified as Leuconostoc citreum with ca...

  17. Competition mechanisms of lactic acid bacteria and bifidobacteria: Fermentative metabolism and colonization

    Tabasco, Raquel; Fernández de Palencia, P.; Fontecha, F. Javier; Peláez, Carmen; Requena, Teresa

    2014-01-01

    Enzyme activities (α- and β-glucosidases, α- and β-galactosidases and β-fructofuranosidase) and organic acid production of four strains of lactic acid bacteria (LAB; Streptococcus thermophilus STY-31, Lactobacillus delbrueckii subsp. bulgaricus LBY-27, Lactobacillus casei LC-01 and Lactobacillus acidophilus LA-5) and Bifidobacterium lactis BB-12 were tested on milk and MRS fermentation broth with glucose, lactose or fructooligosaccharides (FOS) as carbon source. The highest β-galactosidase ac...

  18. Selected Lactic Acid Bacteria Synthesize Antioxidant Peptides during Sourdough Fermentation of Cereal Flours

    Coda, Rossana; Rizzello, Carlo Giuseppe; Pinto, Daniela; Gobbetti, Marco

    2012-01-01

    A pool of selected lactic acid bacteria was used for the sourdough fermentation of various cereal flours with the aim of synthesizing antioxidant peptides. The radical-scavenging activity of water/salt-soluble extracts (WSE) from sourdoughs was significantly (P < 0.05) higher than that of chemically acidified doughs. The highest activity was found for whole wheat, spelt, rye, and kamut sourdoughs. Almost the same results were found for the inhibition of linoleic acid autoxidation. WSE were su...

  19. Evolution of Acetic Acid Bacteria During Fermentation and Storage of Wine

    Joyeux, A.; Lafon-Lafourcade, S.; Ribéreau-Gayon, P.

    1984-01-01

    Acetic acid bacteria were present at all stages of wine making, from the mature grape through vinification to conservation. A succession of Gluconobacter oxydans, Acetobacter pasteurianus, and Acetobacter aceti during the course of these stages was noted. Low levels of A. aceti remained in the wine; they exhibited rapid proliferation on short exposure of the wine to air and caused significant increases in the concentration of acetic acid. Higher temperature of wine storage and higher wine pH ...

  20. Surviving the Acid Test: Responses of Gram-Positive Bacteria to Low pH

    Cotter, Paul D.; Hill, Colin

    2003-01-01

    Gram-positive bacteria possess a myriad of acid resistance systems that can help them to overcome the challenge posed by different acidic environments. In this review the most common mechanisms are described: i.e., the use of proton pumps, the protection or repair of macromolecules, cell membrane changes, production of alkali, induction of pathways by transcriptional regulators, alteration of metabolism, and the role of cell density and cell signaling. We also discuss the reponses of Listeria...

  1. Natural Killer Cells Are Activated by Lactic Acid Bacteria-Matured Dendritic Cells

    Fink, Lisbeth Nielsen; Christensen, Hanne Risager; Frøkiær, Hanne

    of certain lactic acid bacteria has been shown to increase in vivo NK cytotoxicity. Here, we investigated how human gut flora-derived lactobacilli affect NK cells in vitro, by measuring proliferation and IFN-gamma production of human NK cells upon bacterial stimulation. Human peripheral blood NK...... encounter of NK cells with lactic acid bacteria will affect NK cell activation. Such activation of NK cells may potentially skew an on-going or subsequent immune response towards a Th1 response.......Natural killer (NK) cells are cells of the non-specific immune system lysing altered self-cells. A non-cytolytic subset of NK cells may serve a regulatory role by secreting cytokines. Bacteria translocating across the gastrointestinal mucosa are presumed to gain access to NK cells, as consumption...

  2. Isolation and characterization of lactic acid bacteria and yeasts from the Brazilian grape sourdough

    Krischina Singer Aplevicz

    2014-04-01

    Full Text Available Sourdough is a mixture of flour and water fermented by lactic acid bacteria and yeast, with a large use in bakery products. This study was developed with Brazilian grape (Niagara rosada sourdough obtained from spontaneous fermentation. The aim of this work was to characterize genotypic and phenotypically lactic acid bacteria and yeasts isolated from sourdough. The phenotypic identification for bacteria and yeasts was performed by using the kit API50CHL and 20CAUX and the genotypic characterization was performed by sequencing method. A total of four isolated strains were analyzed in this study. Two of these strains were phenotypically and genotypic identified as Lactobacillus paracasei and one as Saccharomyces cerevisiae. Another sample phenotypically identified as Candida pelliculosa did not show the same identity by sequencing. It shows the need to use phenotypic and genotypic characterization associated for the correct microorganism identification.

  3. Short-chain fatty acids produced by intestinal bacteria.

    Topping, D L

    1996-03-01

    The colon is the major site of bacterial colonisation in the human gut and the resident species are predominantly anaerobes. They include potential pathogens but the greater proportion appear to be organisms which salvage energy through the metabolism of undigested carbohydrates and gut secretions. The major products of carbohydrate metabolism are the short chain fatty acids (SCFA), acetate, propionate and butyrate. In addition to general effects (such as lowering of pH) individual acids exert specific effects. All of the major SCFA appear to promote the flow of blood through the colonic vasculature while propionate enhances muscular activity and epithelial cell proliferation. Butyrate appears to promote a normal cell phenotype as well as being a major fuel for colonocytes. Important substrates for bacterial fermentation include non-starch polysaccharides (major components of dietary fibre) but it seems that starch which has escaped digestion in the small intestine (resistant starch) is the major contributor. Oligosaccharides are utilised by probiotic organisms and in the diet, act as prebiotics in promoting their numbers in faeces. High amylose starch is a form of RS and it appears to act as a prebiotic also. Although there is evidence that probiotics such as Bifidobacteria metabolise oligosaccharides and other carbohydrates, there appears to be little evidence to support a change in faecal SCFA excretion. It seems that any health benefits of probiotics are exerted through means other than SCFA. PMID:24394459

  4. Batch fermentations on synthetic mixed sugar and starch medium with amylolytic lactic acid bacteria

    Thomsen, Mette Hedegaard; Guyot, J.P.; Kiel, P.

    2007-01-01

    process. A number of amylolytic lactic acid bacteria have been identified, and in this work, six different strains were tested for their ability to produce alpha-amylase and to utilise all sugars with high lactic acid yield in a medium with a complex composition of free sugars (brown juice) and starch...... brown juice. Brown juice was shown to be an excellent medium for lactic acid fermentation. The aim of this study was to investigate the utilisation of brown juice in the production of polylactic acid, where wheat starch would be added to increase the lactic acid yield and, thus, the feasibility of the....... Lactobacillus plantarum A6 was the only strain that showed both a good lactic acid production and utilisation of starch in this medium. The growth rate of this strain was approximately 0.4 h(-1) and the lactic acid yield was 0.7....

  5. Ammonia production by human faecal bacteria, and the enumeration, isolation and characterization of bacteria capable of growth on peptides and amino acids

    Richardson Anthony J

    2013-01-01

    Full Text Available Abstract Background The products of protein breakdown in the human colon are considered to be detrimental to gut health. Amino acid catabolism leads to the formation of sulfides, phenolic compounds and amines, which are inflammatory and/or precursors to the formation of carcinogens, including N-nitroso compounds. The aim of this study was to investigate the kinetics of protein breakdown and the bacterial species involved. Results Casein, pancreatic casein hydrolysate (mainly short-chain peptides or amino acids were incubated in vitro with suspensions of faecal bacteria from 3 omnivorous and 3 vegetarian human donors. Results from the two donor groups were similar. Ammonia production was highest from peptides, followed by casein and amino acids, which were similar. The amino acids metabolized most extensively were Asp, Ser, Lys and Glu. Monensin inhibited the rate of ammonia production from amino acids by 60% (P = 0.001, indicating the involvement of Gram-positive bacteria. Enrichment cultures were carried out to investigate if, by analogy with the rumen, there was a significant population of asaccharolytic, obligately amino acid-fermenting bacteria (‘hyper-ammonia-producing’ bacteria; HAP in the colon. Numbers of bacteria capable of growth on peptides or amino acids alone averaged 3.5% of the total viable count, somewhat higher than the rumen. None of these were HAP, however. The species enriched included Clostridium spp., one of which was C. perfringens, Enterococcus, Shigella and Escherichia coli. Conclusions Protein fermentation by human faecal bacteria in the absence of sugars not only leads to the formation of hazardous metabolic products, but also to the possible proliferation of harmful bacteria. The kinetics of protein metabolism were similar to the rumen, but HAP bacteria were not found.

  6. Competitive selection of lactic acid bacteria that persist in the human oral cavity

    Snel, J.; Marco, M.L.; Kingma, F.; Noordman, W.M.; Rademaker, J.; Kleerebezem, M.

    2011-01-01

    Lactic acid bacteria (LAB) might offer opportunities as oral probiotics provided candidate strains persist in the mouth. After intake of a mixture of 69 LAB, strains of Lactobacillus fermentum and Lactobacillus salivarius were especially recovered. Coaggregation with other microbes is likely not a prerequisite for persistence since L. salivarius strongly coaggregated with typical oral cavity isolates, whereas L. fermentum failed to display this phenotype.

  7. Distinct gut-derived lactic acid bacteria elicit divergent dendritic cell-mediated NK cell responses

    Fink, Lisbeth Nielsen; Zeuthen, Louise Hjerrild; Christensen, Hanne;

    2007-01-01

    Lactic acid bacteria (LAB) are abundant in the gastrointestinal tract where they continuously regulate the immune system. NK cells are potently activated by dendritic cells (DCs) matured by inflammatory stimuli, and NK cells are present in the gut epithelium and in mesenteric lymph nodes, but it is...

  8. Potential and opportunities for use of recombinant lactic acid bacteria in human health

    Hanniffy, S.; Wiedermann, U.; Repa, A.; Mercenier, A.; Daniel, C.; Fioramonti, J.; Tlaskalová, Helena; Kozáková, Hana; Israelsen, H.; Madsen, S.; Vrang, A.; Hols, P.; Delcour, J.; Bron, P.; Kleerebezem, M.; Wells, J.

    2004-01-01

    Roč. 56, - (2004), s. 1-64. ISSN 0065-2164 Grant ostatní: EC contract(XE) QLK3-CT-QLK3-CT-2000-00340 Keywords : lactic acid bacteria * human health Subject RIV: EE - Microbiology, Virology Impact factor: 1.156, year: 2004

  9. TECHNOLOGICAL AND FUNCTIONAL PROPERTIES OF LACTIC ACID BACTERIA: THE IMPORTANCE OF THESE MICROORGANISMS FOR FOOD

    Amanda de Souza Motta

    2015-12-01

    Full Text Available Eacters of coccus or rods Gram-positive, catalase negative, non-sporulating, which produce lactic acid as the major end product during the fermentation of carbohydrates. When applied on food, provides beneficial effects to consumers through its functional and technological properties. With this the present review article, explore the potential application of lactic acid bacteria in food. The following genera are considered the principal lactic acid bacteria: Aerococcus, Carnobacterium, Enterococcus, Lactobacillus, Lactococcus, Leuconostoc, Oenococcus, Pediococcus, Streptococcus, Tetragenococcus, Vagococcus and Weissella. These cultures have been used as starter or adjunct cultures for the fermentation of foods and beverages due to their contributions to the sensorial characteristics of these products and by microbiological stability. Their probiotic properties have also been investigated. More recent studies by indigenous cultures have received increased attention in light of the search for isolated cultures of a given raw material and a certain region. These microorganisms are being investigated for its functional and technological potential that may be applied in product development with its own characteristics and designation of origin. Those properties will be discussed in the present review in order to highlight the performance of these bacteria and the high degree of control over the fermentation process and standardization of the final product. The use of autochthonous cultures will be considered due the increase of studies of new cultures of lactic acid bacteria isolated of milk and meat of distinct products.

  10. Improving farm management by modeling the contamination of farm tank milk with butyric acid bacteria

    Vissers, M.M.M.; Driehuis, F.; Giffel, te M.C.; Jong, de P.; Lankveld, J.M.G.

    2006-01-01

    Control of contamination of farm tank milk (FTM) with the spore-forming butyric acid bacteria (BAB) is important to prevent the late-blowing defect in semi-hard cheeses. The risk of late blowing can be decreased via control of the contamination level of FTM with BAB. A modeling approach was applied

  11. Intrinsic nitric oxide-stimulatory activity of lipoteichoic acids from different Gram-positive bacteria

    Zídek, Zdeněk; Farghali, H.; Kmoníčková, Eva

    2010-01-01

    Roč. 23, č. 4 (2010), s. 300-310. ISSN 1089-8603 R&D Projects: GA ČR GA305/08/0535 Institutional research plan: CEZ:AV0Z50390512 Keywords : Lipoteichoic acid * Gram-positive bacteria * Nitric oxide Subject RIV: FR - Pharmacology ; Medidal Chemistry Impact factor: 3.384, year: 2010

  12. Inducible gene expression and environmentally regulated genes in lactic acid bacteria

    Kok, Jan

    1996-01-01

    Relatively recently, a number of genes and operons have been identified in lactic acid bacteria that are inducible and respond to environmental factors. Some of these genes/operons had been isolated and analysed because of their importance in the fermentation industry and, consequently, their transc

  13. Surface of Lactic Acid Bacteria: Relationships between Chemical Composition and Physicochemical Properties

    Boonaert, C J; Rouxhet, Paul

    2000-01-01

    The surface chemical composition and physicochemical properties (hydrophobicity and zeta potential) of two lactic acid bacteria, Lactococcus lactis subsp. lactis bv. diacetilactis and Lactobacillus helveticus, have been investigated using cells harvested in exponential or stationary growth phase. The surface composition determined by X-ray photoelectron spectroscopy (XPS) was converted into a molecular composition in terms of proteins, polysaccharides, and hydrocarbonlike compounds. The conce...

  14. Systems biology and metabolic engineering of lactic acid bacteria for improved fermented foods

    Flahaut, N.A.L.; Vos, de W.M.

    2014-01-01

    Lactic acid bacteria have long been used in industrial dairy and other food fermentations that make use of their metabolic activities leading to products with specific organoleptic properties. Metabolic engineering is a rational approach to steer fermentations toward the production of desired compou

  15. Protective Effect of Adonitol on Lactic Acid Bacteria Subjected to Freeze-Drying

    de Valdéz, Graciela F.; de Giori, Graciela S.; de Ruiz Holgado, Aída A. P.; Oliver, Guillermo

    1983-01-01

    The protective effects of glycerol, adonitol, and four other related polyhydric alcohols on lactic acid bacteria subjected to freeze-drying were examined. The presence of adonitol in the suspending medium markedly protected the viabilities of the 12 stains tested. Dulcitol, mannitol, m-inositol, and sorbitol were found to provide little or no protection.

  16. Towards metagenome-scale models for industrial applications-the case of Lactic Acid Bacteria

    Branco Dos Santos, F.; Vos, de W.M.; Teusink, B.

    2013-01-01

    We review the uses and limitations of modelling approaches that are in use in the field of Lactic Acid Bacteria (LAB). We describe recent developments in model construction and computational methods, starting from application of such models to monocultures. However, since most applications in food b

  17. Diversity, vitality and activities of intestinal lactic acid bacteria and bifidobacteria assessed by molecular approaches

    Vaughan, E.E.; Heilig, G.H.J.; Ben-Amor, K.; Vos, de W.M.

    2005-01-01

    While lactic acid bacteria and bifidobacteria have been scientifically important for over a century, many of these are marketed today as probiotics and have become a valuable and rapidly expanding sector of the food market that is leading functional foods in many countries. The human gastro-intestin

  18. Comparison of phenotypic and molecular tests to identify lactic acid bacteria

    Paula Mendonça Moraes; Luana Martins Perin; Abelardo Silva Júnior; Luís Augusto Nero

    2013-01-01

    Twenty-nine lactic acid bacteria (LAB) isolates were submitted for identification using Biolog, API50CHL, 16S rDNA sequencing, and species-specific PCR reactions. The identification results were compared, and it was concluded that a polyphasic approach is necessary for proper LAB identification, being the molecular analyzes the most reliable.

  19. Pediocin PA-1, a wide-spectrum bacteriocin from lactic acid bacteria

    Rodriguez, JM; Martinez, MI; Kok, J

    2002-01-01

    Pediocin PA-1 is a broad-spectrum lactic acid bacteria bacteriocin that shows a particularly strong activity against Listeria monocytogenes, a foodborne pathogen of special concern among the food industries. This antimicrobial peptide is the most extensively studied class IIa (or pediocin family) ba

  20. Characterization of airag collected in Ulaanbaatar, Mongolia with emphasis on isolated lactic acid bacteria

    Choi, Suk-Ho

    2016-01-01

    Background Airag, alcoholic sour-tasting beverage, has been traditionally prepared by Mongolian nomads who naturally ferment fresh mares’ milk. Biochemical and microbiological compositions of airag samples collected in Ulaanbaatar, Mongolia and physiological characteristics of isolated lactic acid bacteria were investigated. Methods Protein composition and biochemical composition were determined using sodium dodecyl sulfate-gel electrophoresis and high performance liquid chromatography, respe...

  1. Minimizing the level of butyric acid bacteria spores in farm tank milk

    Vissers, M.M.M.; Driehuis, F.; Giffel, M.C.T.; Jong, de P.; Lankveld, J.M.G.

    2007-01-01

    A year-long survey of 24 dairy farms was conducted to determine the effects of farm management on the concentrations of butyric acid bacteria (BAB) spores in farm tank milk (FTM). The results were used to validate a control strategy derived from model simulations. The BAB spore concentrations were m

  2. Bacteria and Archaea in acidic environments and a key to morphological identification

    Robbins, E.I.

    2000-01-01

    Natural and anthropogenic acidic environments are dominated by bacteria and Archaea. As many as 86 genera or species have been identified or isolated from pH <4.5 environments. This paper reviews the worldwide literature and provide tables of morphological characteristics, habitat information and a key for light microscope identification for the non-microbiologist.

  3. Biohydrogenation of Linoleic Acid by Lactic Acid Bacteria for the Production of Functional Cultured Dairy Products: A Review

    Gabriela Christina Kuhl; Juliano De Dea Lindner

    2016-01-01

    Conjugated linoleic acid (CLA) isomers have attracted significant attention due to their important physiological properties, which have been observed in humans. Many lactic acid bacteria (LAB) demonstrate the ability to produce CLA isomers (C18:2 cis-9, trans-11 and C18:2 trans-10, cis-12) from the linoleic acid (LA) present in milk or in synthetic media. CLA isomers can be synthesized in vitro by LAB using vegetable oils rich in LA. The aim of this review is to present an update on the studi...

  4. Can electrophoretic types of listeria monocytogenes induce different sensitivity to lactic acid bacteria bacteriocins?

    Dimitrijević Mirjana

    2005-01-01

    Full Text Available The aim of this study was to find if electrophoretic types (ETs of Listeria monocytogenes, typed by multilocus enzyme electrophoresis (MEE, can induce different sensitivity to lactic acid bacteria bacteriocins. Bacteriocins are extracellular peptides or protein molecules, produced by lactic acid bacteria, which not only have bactericidal or bacteriostatic effects, on usually closely related bacterial strains, but also they may have destructive effects on some not so closely related Gram positive bacteria, for example Listeria monocytogenes. Listeria monocytogenes is commonly found in the intestines of humans and animals, in milk, soil, leafy vegetables and in food processing environments. These bacteria have been isolated in a variety of foods, including raw and cooked poultry, meat, seafood, salads and sandwiches. Many techniques for typing of Listeria monocytogenes in foodstuffs, have been developed for the purpose of identification of the origin of infection for epidemiological and epizootological studies. Among the 98 examined isolates of Listeria monocytogenes (50 clinical/human and 48 from food of animal origin 32 electrophoretic types have been detected. Bacteriocins, which we have used in the study, originated from the following lacic acid bacteria: Lactobacillus sake 148, Lactococcus UW, Lactobacillus sake 706, Pediococcus 347 and Lactobacillus sake 265. In this study, on the basis of a dendogram, our results indicate that a reliable relationship between genetic distance of Listeria monocytogenes electrophoretic types and their sensitivity to lactic acid bacteria bacteriocins cannot been found. MEE may, however, be of future benefit in establishing links between isolates from human disease cases and thus be useful in establishing the epidemiology of not only sporadic cases, but of outbreaks of listeriosis, as well.

  5. Genome-wide Studies of Mycolic Acid Bacteria: Computational Identification and Analysis of a Minimal Genome

    Kamanu, Frederick Kinyua

    2012-12-01

    The mycolic acid bacteria are a distinct suprageneric group of asporogenous Grampositive, high GC-content bacteria, distinguished by the presence of mycolic acids in their cell envelope. They exhibit great diversity in their cell and morphology; although primarily non-pathogens, this group contains three major pathogens Mycobacterium leprae, Mycobacterium tuberculosis complex, and Corynebacterium diphtheria. Although the mycolic acid bacteria are a clearly defined group of bacteria, the taxonomic relationships between its constituent genera and species are less well defined. Two approaches were tested for their suitability in describing the taxonomy of the group. First, a Multilocus Sequence Typing (MLST) experiment was assessed and found to be superior to monophyletic (16S small ribosomal subunit) in delineating a total of 52 mycolic acid bacterial species. Phylogenetic inference was performed using the neighbor-joining method. To further refine phylogenetic analysis and to take advantage of the widespread availability of bacterial genome data, a computational framework that simulates DNA-DNA hybridisation was developed and validated using multiscale bootstrap resampling. The tool classifies microbial genomes based on whole genome DNA, and was deployed as a web-application using PHP and Javascript. It is accessible online at http://cbrc.kaust.edu.sa/dna_hybridization/ A third study was a computational and statistical methods in the identification and analysis of a putative minimal mycolic acid bacterial genome so as to better understand (1) the genomic requirements to encode a mycolic acid bacterial cell and (2) the role and type of genes and genetic elements that lead to the massive increase in genome size in environmental mycolic acid bacteria. Using a reciprocal comparison approach, a total of 690 orthologous gene clusters forming a putative minimal genome were identified across 24 mycolic acid bacterial species. In order to identify new potential drug

  6. The influence of stress conditions on the growth of selected lactic acid bacteria

    A study was undertaken to determine the effects of certain stress conditions on selected lactic acid bacteria. Where recontamination occurred, lactic acid bacteria was already the dominant bacterial group, with counts of higher than 106/g in vacuum-packaged 'shelf stable' meat products after 1 week storage at 25 and 37 degrees Celsius respectively. Some of the isolates were capable of growing at a pH of 3,9. The minimum pH for growth of a specific culture was dependant on the type of acid that was used to lower the pH. Lactic and acetic acid had the highest inhibitory action. Hydrochloric and citric acid showed similar inhibitory effects, while the effects when using ascorbic acid or gluconic acid for lowering the pH were also fairly similar. Increase in the activity of certain lactic acid bacteria was noticed where the ratio of undissociated to dissociated citric acid in the medium was increased. After exceeding a concentration of 0,048 moles/l undissosiated citric acid in the medium, the activity of the majority of cultures was progressively inhibited. This phenomenon was also found with acetic acid for certain cultures. Selected lactic acid bacteria were resistant to an water activity (a (sub w)) of 0,94 in MRS broth, where NaCl or glycerol was used as a humectant. The minimum a (sub w) for growth was dependent on the type of humectant used. Concentrations of sodium benzoate and potassium sorbate were necessary to inhibit the majority of strains. The % inhibition by sodium benzoate and methyl paraben did not significantly change with a lowering in the pH of the growth medium. Except in the case of lactic acid, the different acids used to lower the pH of the medium did not have a significant effect on the % inhibition by the chemical preservatives. For the cocci, gamma D10 values of between 0,82 and 1,29 kGy were recorded, whereas the lactobacilli were less resistant to gamma rays, with D10 values of between 0,21 and 0,54 kGy

  7. Physicochemical Cell Surface and Adhesive Properties of Coryneform Bacteria Related to the Presence and Chain Length of Mycolic Acids

    1993-01-01

    The presence and chain length of mycolic acids of bacteria of the genera Corynebacterium, Rhodococcus, Gordona, Mycobacterium, and Arthrobacter and of coryneform bacteria containing a type B peptidoglycan were related to the cell surface hydrophobicity of the bacteria, which in turn was related to adhesion of the cells to defined surfaces such as Teflon and glass. The origin of the overall negative charge of these bacteria is discussed.

  8. Phytic acid degrading lactic acid bacteria in tef-injera fermentation.

    Fischer, Maren M; Egli, Ines M; Aeberli, Isabelle; Hurrell, Richard F; Meile, Leo

    2014-11-01

    Ethiopian injera, a soft pancake, baked from fermented batter, is preferentially prepared from tef (Eragrostis tef) flour. The phytic acid (PA) content of tef is high and is only partly degraded during the fermentation step. PA chelates with iron and zinc in the human digestive tract and strongly inhibits their absorption. With the aim to formulate a starter culture that would substantially degrade PA during injera preparation, we assessed the potential of microorganisms isolated from Ethiopian household-tef fermentations to degrade PA. Lactic acid bacteria (LAB) were found to be among the dominating microorganisms. Seventy-six isolates from thirteen different tef fermentations were analyzed for phytase activity and thirteen different isolates of seven different species were detected to be positive in a phytase screening assay. In 20-mL model tef fermentations, out of these thirteen isolates, the use of Lactobacillus (L.) buchneri strain MF58 and Pediococcus pentosaceus strain MF35 resulted in lowest PA contents in the fermented tef of 41% and 42%, respectively of its initial content. In comparison 59% of PA remained when spontaneously fermented. Full scale tef fermentation (0.6L) and injera production using L. buchneri MF58 as culture additive decreased PA in cooked injera from 1.05 to 0.34±0.02 g/100 g, representing a degradation of 68% compared to 42% in injera from non-inoculated traditional fermentation. The visual appearance of the pancakes was similar. The final molar ratios of PA to iron of 4 and to zinc of 12 achieved with L. buchneri MF58 were decreased by ca. 50% compared to the traditional fermentation. In conclusion, selected LAB strains in tef fermentations can degrade PA, with L. buchneri MF58 displaying the highest PA degrading potential. The 68% PA degradation achieved by the application of L. buchneri MF58 would be expected to improve human zinc absorption from tef-injera, but further PA degradation is probably necessary if iron absorption has to

  9. Spatio-Temporal Variations of High and Low Nucleic Acid Content Bacteria in an Exorheic River

    Ma, Lili; Ji, Yurui; Bartlam, Mark; Wang, Yingying

    2016-01-01

    Bacteria with high nucleic acid (HNA) and low nucleic acid (LNA) content are commonly observed in aquatic environments. To date, limited knowledge is available on their temporal and spatial variations in freshwater environments. Here an investigation of HNA and LNA bacterial abundance and their flow cytometric characteristics was conducted in an exorheic river (Haihe River, Northern China) over a one year period covering September (autumn) 2011, December (winter) 2011, April (spring) 2012, and July (summer) 2012. The results showed that LNA and HNA bacteria contributed similarly to the total bacterial abundance on both the spatial and temporal scale. The variability of HNA on abundance, fluorescence intensity (FL1) and side scatter (SSC) were more sensitive to environmental factors than that of LNA bacteria. Meanwhile, the relative distance of SSC between HNA and LNA was more variable than that of FL1. Multivariate analysis further demonstrated that the influence of geographical distance (reflected by the salinity gradient along river to ocean) and temporal changes (as temperature variation due to seasonal succession) on the patterns of LNA and HNA were stronger than the effects of nutrient conditions. Furthermore, the results demonstrated that the distribution of LNA and HNA bacteria, including the abundance, FL1 and SSC, was controlled by different variables. The results suggested that LNA and HNA bacteria might play different ecological roles in the exorheic river. PMID:27082986

  10. A Novel Lactic Acid Bacteria Growth-stimulating Peptide from Broad Bean (Vicia faba . Protein Hydrolysates

    Ping Xiao

    2015-03-01

    Full Text Available In this study, broad bean protein hydrolysates (BPH produced by alcalase with strong-stimulating activity for lactic acid bacteria (LAB was first time reported. In order to obtain the key peptide that have growth-stimulating activity for lactic acid bacteria (LAB, gel filtration chromatography and Reverse Phase High Performance Liquid Chromatography (RP-HPLC were applied to isolate and purify the peptides from BPH. Finally, F4-2 elicited the highest activity for LAB, corresponding to amino acid sequence Ser-Ala-Gln (304.10Da was identified by Matrix-Assisted Laser Desorption/Ionization Time of Flight Mass Spectrometry (MALDI-TOF/TOF MS/MS. Thus, this study shows that broad bean peptide is a good source to promote the LAB growth and this function is reported for the first time.

  11. Genomewide expression analysis in amino acid-producing bacteria using DNA microarrays.

    Polen, Tino; Wendisch, Volker F

    2004-01-01

    DNA microarray technology has become an important research tool for biotechnology and microbiology. It is now possible to characterize genetic diversity and gene expression in a genomewide manner. DNA microarrays have been applied extensively to study the biology of many bacteria including Escherichia coli, but only recently have they been developed for the Gram-positive Corynebacterium glutamicum. Both bacteria are widely used for biotechnological amino acid production. In this article, in addition to the design and generation of microarrays as well as their use in hybridization experiments and subsequent data analysis, we describe recent applications of DNA microarray technology regarding amino acid production in C. glutamicum and E. coli. We also discuss the impact of functional genomics studies on fundamental as well as applied aspects of amino acid production with C. glutamicum and E. coli. PMID:15304751

  12. Isolation and identification of indigenous lactic acid bacteria from North Sumatra river buffalo milk

    Heni Rizqiati

    2015-06-01

    Full Text Available Buffalo milk is a source of various lactic acid bacteria (LAB which is potential as culture starter as well as the probiotic. This study was conducted to isolate and identify LAB from indigenous North Sumatra river buffalo milk. Lactic acid bacteria was isolated and grown in medium De Man Rogosa Sharpe Agar (MRSA. The isolation was conducted to obtain pure isolate. The identification of LAB was studied in terms of morphology, physiology, biochemistry and survival on low pH. Morphology tests were conducted by Gram staining and cell forming; physiology tests were conducted for growing viability at pH 4.5 and temperature at 45oC; whereas biochemistry tests were conducted for CO2, dextran and NH3 productions. Determination of LAB species was conducted using Analytical Profile Index (API test CHL 50. Results of identification showed that 41 isolates were identified as LAB with Gram-positive, catalase-negative, rod and round shaped characteristics. Resistance test done to low pH (pH 2 for the lactic acid bacteria showed decrease of bacteria viability up to1.24±0.68 log cfu/ml. The resistant isolates at low pH were L12, L16, L17, L19, L20, M10, P8, S3, S19 and S20. Identification with API test CHL 50 for 10 isolates showed that four isolates were identified as Lactobacillus plantarum, L. brevis, L. pentosus and Lactococuslactis.

  13. Development of radiation sterilized dip slides for enumerating lactic acid bacteria and total count in foodstuffs

    Eisenberg, E.; Padova, R.; Kirsch, E.; Weissman, Sh.; Hirshfeld, T.; Shenfeld, A.

    APT agar (APT) used for enumeration of lactic acid bacteria and Plate Count agar (PCA) applied for total count were sterilized by gamma radiation using radiation dose of 10-15 kGy. Radiosterilized PCA and APT modified by adding catalase prior to irradiation, or APT with increased content of yeast extract performed, as well as, the heat sterilized commercial media. Growth performance was evaluated on several strains of microorganisms, as well as, by enumeration of bacteria in food products. Radiosterilization of culture media in final packaging, can be applied to produce dip slide kits containing PCA or APT.

  14. Typing some of lactic acid bacteria in Syria using PCR and FT-IR techniques

    Lactic Acid Bacteria (LAB) are considered to be the most useful microorganisms. They are beneficial in flavoring foods, inhibiting pathogenic as well as spoilage bacteria in food products. The isolates of LAB were obtained from traditional Syrian dairy products (white cheese and curdled yogurt) obtained from different regions in Syria. The isolates were subjected to phenotypic characterization analyses. The PCR technique of bacterial DNA was evaluated as an advanced tool for the identification of LAB. It was found that strains: E. faecium, E. faecalis and S. thermophilus dominate in white cheese and in yogurt. Our results demonstrated that we could identify LAB using Fourier transform infrared spectroscopy (FT-IR) patterns. (Authors)

  15. Lactic acid bacteria from Jijel's traditional butter: Isolation, identification and major technological traits

    Idoui, Tayeb

    2008-12-01

    Full Text Available Twenty seven (27 lactic acid bacteria were isolated from Jijel’s traditional butter. These strains belong to three genera: Lactococcus, Lactobacillus and Leuconostoc. The results showed that Lactobacillus plantarum was the predominant species in this traditional butter. It appears that these strains have some interesting technological properties.Se aíslan veintisiete (27 bacterias acidolácticas de la mantequilla tradicional de Jijel. Éstas pertenecen a los géneros Lactococcus, Lactobacillus y Leuconostoc. Los resultados muestran que Lactobacillus plantarum es la especie predominante en dicha mantequilla. Diversas cepas presentan algunas propiedades tecnológicas interesantes.

  16. Development of radiation sterilized dip slides for enumerating lactic acid bacteria and total count in foodstuffs

    APT agar (APT) used for enumeration of lactic acid bacteria and Plate Count agar (PCA) applied for total count were sterilized by gamma radiation using radiation dose of 10-15 kGy. Radiosterilized PCA and APT modified by adding catalase prior to irradiation, or APT with increased content of yeast extract performed, as well as, the heat sterilized commercial media. Growth performance was evaluated on several strains of microorganisms, as well as, by enumeration of bacteria in food products. Radiosterilization of culture media in final packaging, can be applied to produce dip slide kits containing PCA or APT. (author)

  17. Typing some of lactic acid bacteria in Syria using PCR and FT-IR techniques

    Lactic Acid Bacteria (LAB) are considered to be the most useful microorganisms. They are beneficial in flavoring foods, inhibiting pathogenic as well as spoilage bacteria in food products. The isolates of LAB were obtained from traditional Syrian dairy products (white cheese and curdled yogurt) obtained from different regions in Syria. The isolates were subjected to phenotypic characterization analyses. The PCR technique of bacterial DNA was evaluated as an advanced tool for the identification of LAB. It was found that strains: E. faecium, E. faecalis and S. thermophilus dominate in white cheese and in yogurt. Our results demonstrated that we could identify LAB using Fourier transform infrared spectroscopy (FT-IR) patterns. (author)

  18. Behavior of Psychrotrophic Lactic Acid Bacteria Isolated from Spoiling Cooked Meat Products

    Hamasaki, Yoshikatsu; Ayaki, Mitsuko; Fuchu, Hidetaka; Sugiyama, Masaaki; Morita, Hidetoshi

    2003-01-01

    Three kinds of lactic acid bacteria were isolated from spoiling cooked meat products stored below 10°C. They were identified as Leuconostoc mesenteroides subsp. mesenteroides, Lactococcus lactis subsp. lactis, and Leuconostoc citreum. All three strains grew well in MRS broth at 10°C. In particular, L. mesenteroides subsp. mesenteroides and L. citreum grew even at 4°C, and their doubling times were 23.6 and 51.5 h, respectively. On the other hand, although the bacteria were initially below the...

  19. Lactic Acid Bacteria Inducing a Weak Interleukin-12 and Tumor Necrosis Alpha Response in Human Dendritic Cells Inhibit Strongly Stimulating Lactic Acid Bacteria but Act Synergistically with Gram-Negative Bacteria

    Zeuthen, Louise Hjerrild; Christensen, Hanne Risager; Frøkiær, Hanne

    2006-01-01

    The development and maintenance of immune homeostasis indispensably depend on signals from the gut flora. Lactic acid bacteria (LAB), which are gram-positive (G+) organisms, are plausible significant players and have received much attention. Gram-negative (G-) commensals, such as members of the...... family Enterobacteriaceae, may, however, be immunomodulators that are as important as G+ organisms but tend to be overlooked. Dendritic cells (DCs) are crucial immune regulators, and therefore, the present study aimed at investigating differences among human gut flora-derived LAB and G- bacteria in their...... patterns of DC polarization. Human monocyte-derived DCs were exposed to UV-killed bacteria, and cytokine secretion and surface marker expression were analyzed. Profound differences in the DC polarization patterns were found among the strains. While strains of LAB varied greatly in their capacity to induce...

  20. Isolation of acetic, propionic and butyric acid-forming bacteria from biogas plants.

    Cibis, Katharina Gabriela; Gneipel, Armin; König, Helmut

    2016-02-20

    In this study, acetic, propionic and butyric acid-forming bacteria were isolated from thermophilic and mesophilic biogas plants (BGP) located in Germany. The fermenters were fed with maize silage and cattle or swine manure. Furthermore, pressurized laboratory fermenters digesting maize silage were sampled. Enrichment cultures for the isolation of acid-forming bacteria were grown in minimal medium supplemented with one of the following carbon sources: Na(+)-dl-lactate, succinate, ethanol, glycerol, glucose or a mixture of amino acids. These substrates could be converted by the isolates to acetic, propionic or butyric acid. In total, 49 isolates were obtained, which belonged to the phyla Firmicutes, Tenericutes or Thermotogae. According to 16S rRNA gene sequences, most isolates were related to Clostridium sporosphaeroides, Defluviitoga tunisiensis and Dendrosporobacter quercicolus. Acetic, propionic or butyric acid were produced in cultures of isolates affiliated to Bacillus thermoamylovorans, Clostridium aminovalericum, Clostridium cochlearium/Clostridium tetani, C. sporosphaeroides, D. quercicolus, Proteiniborus ethanoligenes, Selenomonas bovis and Tepidanaerobacter sp. Isolates related to Thermoanaerobacterium thermosaccharolyticum produced acetic, butyric and lactic acid, and isolates related to D. tunisiensis formed acetic acid. Specific primer sets targeting 16S rRNA gene sequences were designed and used for real-time quantitative PCR (qPCR). The isolates were physiologically characterized and their role in BGP discussed. PMID:26779817

  1. STUDY ON PROBIOTIC POTENTIAL AND LABORATORY SCALE PRODUCTION OF LACTIC ACID BACTERIA

    Ambule A.H.

    2012-08-01

    Full Text Available Lactic acid bacteria were isolated from dairy food. They were identified on the basis of theirmorphological, cultural and biochemical characterastics.The cell free supernatant of lactic acid bacteria were ableto inhibit the growth ofE.coli,Klebsiella aerogens,Salmonella spp. , S.aureus, P.mirabilies and Ps .aeruginosa.The probiotic properties of isolate of lactic acid bacteria (LAB-VI were investigated. The LAB-VI wassusceptible to antibiotics like ampicillin, gentamycin, ciprofloxacin, ofloxacin and streptomycin. Maximumbiomass of LAB – VI was obtained at pH: 5, inoculum size 4% v/v & incubation period 48 hrs. Efficacy ofcoconut extract medium (Type I and Type II on growth, lactic acid and hydrogen peroxide production by LAB-VI was studied using laboratory bioreactor in batch fermentation. The type II coconut extract medium gave higherbiomass yield than type I (coconut extract medium. The biomass production from MRS was more than coconutextract medium. The formulated coconut extract medium (Type II should be used to substitute MRS, since thesubstrate is economical, readily available and reduce quantity of the expensive supplements. The bacteriocinactivity of the bacteriocin from fermented Type I & Type II coconut extract media were 1:6 & 1:8 respectively.The bacteriocin activity was tested againstKlebsiella aerogens

  2. Lactic acid bacteria convert glucosinolates to nitriles efficiently yet differently from enterobacteriaceae.

    Mullaney, Jane A; Kelly, William J; McGhie, Tony K; Ansell, Juliet; Heyes, Julian A

    2013-03-27

    Glucosinolates from the genus Brassica can be converted into bioactive compounds known to induce phase II enzymes, which may decrease the risk of cancers. Conversion via hydrolysis is usually by the brassica enzyme myrosinase, which can be inactivated by cooking or storage. We examined the potential of three beneficial bacteria, Lactobacillus plantarum KW30, Lactococcus lactis subsp. lactis KF147, and Escherichia coli Nissle 1917, and known myrosinase-producer Enterobacter cloacae to catalyze the conversion of glucosinolates in broccoli extract. Enterobacteriaceae consumed on average 65% glucoiberin and 78% glucoraphanin, transforming them into glucoiberverin and glucoerucin, respectively, and small amounts of iberverin nitrile and erucin nitrile. The lactic acid bacteria did not accumulate reduced glucosinolates, consuming all at 30-33% and transforming these into iberverin nitrile, erucin nitrile, sulforaphane nitrile, and further unidentified metabolites. Adding beneficial bacteria to a glucosinolate-rich diet may increase glucosinolate transformation, thereby increasing host exposure to bioactives. PMID:23461529

  3. Aflatoxin B1 binding capacity of autochthonous strains of lactic acid bacteria.

    Fazeli, Mohammad R; Hajimohammadali, M; Moshkani, Azamossadat; Samadi, Nasrin; Jamalifar, Hossein; Khoshayand, Mohammad R; Vaghari, Elham; Pouragahi, Samieh

    2009-01-01

    Some foods are prone to contamination with aflatoxins, with detrimental effect on human health. Lactic acid bacteria have been reported to bind aflatoxins and remove them from foods and feeds. Reduction of aflatoxin B1 (AFB1) from the liquid media by the autochthonous lactic acid bacteria (Lactobacillus casei, Lactobacillus plantarum, and Lactobacillus fermentum) isolated from traditional Iranian sourdough and dairy products is reported in the current study. The effect of incubation time on the binding capacity of the strains to AFB1 was also investigated. Duplicates of individual bacteria with population equivalent to 2 X 10(10) CFU/ml were incubated in the presence of AFB1 at 37 degrees C for a period of 72 h, and the amounts of unbound AFB1 were quantitated by reverse-phase high-performance liquid chromatography. All the strains were capable of removal of AFB1, and the reduction of AFB1 ranged from 25 to 61% throughout the incubation period. Removal of AFB1 was a rapid process, with approximately 61 and 56% of the toxin taken instantly by L. fermentum and L. plantarum, respectively. Binding was of a reversible nature, and some of the bound AFB1 was released into the media by the repeated centrifugation and resuspension of the cell pellets. The stability of the bacteria-toxin complex was strain dependent, and L. casei was a stronger binder of AFB1 compared with the other bacteria. No toxin release was observed after 24 h. These findings tend to suggest that certain novel probiotic bacteria with high aflatoxin binding capacity could be selected for detoxification of foods. PMID:19205485

  4. Impact of gluconic fermentation of strawberry using acetic acid bacteria on amino acids and biogenic amines profile.

    Ordóñez, J L; Sainz, F; Callejón, R M; Troncoso, A M; Torija, M J; García-Parrilla, M C

    2015-07-01

    This paper studies the amino acid profile of beverages obtained through the fermentation of strawberry purée by a surface culture using three strains belonging to different acetic acid bacteria species (one of Gluconobacter japonicus, one of Gluconobacter oxydans and one of Acetobacter malorum). An HPLC-UV method involving diethyl ethoxymethylenemalonate (DEEMM) was adapted and validated. From the entire set of 21 amino acids, multiple linear regressions showed that glutamine, alanine, arginine, tryptophan, GABA and proline were significantly related to the fermentation process. Furthermore, linear discriminant analysis classified 100% of the samples correctly in accordance with the microorganism involved. G. japonicus consumed glucose most quickly and achieved the greatest decrease in amino acid concentration. None of the 8 biogenic amines were detected in the final products, which could serve as a safety guarantee for these strawberry gluconic fermentation beverages, in this regard. PMID:25704705

  5. Metabolic engineering of lactic acid bacteria and characterization of novel enzymes for the production of industrially important compounds

    Aarnikunnas, Johannes Sakari

    2006-01-01

    Lactic acid bacteria (LAB) are a heterogeneous group of gram-positive bacteria that produce lactic acid as their main end-product during sugar fermentation. Because the LAB are able to rapidly lower pH through acid formation and additionally produce many flavor compounds, they are commonly used in the food and feed industry. LAB are also attractive organisms for metabolic engineering because their energy metabolism is generally not connected to their biosynthetic activity. Therefore, their su...

  6. Molecular Identification of Lactic Acid Bacteria Producing Antimicrobial Agents from Bakasang, An Indonesian Traditional Fermented Fish Product

    Helen Joan Lawalata

    2015-11-01

    Full Text Available AbstractTwenty seven strains of lactic acid bacteria (LAB were isolated from bakasang, Indonesian traditional fermented fish product. In general, LAB have inhibitory activity againts pathogenic bacteria and spoilage bacteria. Screening for antimicrobia activity of isolates were performed with well-diffusion method. One isolate that was designed as Pediococcus BksC24 was the strongest against bacteria pathogenic and spoilage bacteria. This strain was further identified by 16S rRNA gen sequence comparison. Isolates LAB producing antimicrobial agents from bakasang were identified as Pediococcus acidilactici.Keywords : Bakasang, LAB, antimicrobial, phenotypic characteristics, 16S rRNA gene

  7. Novel Simplified and Rapid Method for Screening and Isolation of Polyunsaturated Fatty Acids Producing Marine Bacteria

    Ashwini Tilay

    2012-01-01

    Full Text Available Bacterial production of polyunsaturated fatty acids (PUFAs is a potential biotechnological approach for production of valuable nutraceuticals. Reliable method for screening of number of strains within short period of time is great need. Here, we report a novel simplified method for screening and isolation of PUFA-producing bacteria by direct visualization using the H2O2-plate assay. The oxidative stability of PUFAs in growing bacteria towards added H2O2 is a distinguishing characteristic between the PUFAs producers (no zone of inhibition and non-PUFAs producers (zone of inhibition by direct visualization. The confirmation of assay results was performed by injecting fatty acid methyl esters (FAMEs produced by selected marine bacteria to Gas Chromatography-Mass Spectrometry (GCMS. To date, this assay is the most effective, inexpensive, and specific method for bacteria producing PUFAs and shows drastically reduction in the number of samples thus saves the time, effort, and cost of screening and isolating strains of bacterial PUFAs producers.

  8. Application of Lactic Acid Bacteria (LAB) in freshness keeping of tilapia fillets as sashimi

    Cao, Rong; Liu, Qi; Chen, Shengjun; Yang, Xianqing; Li, Laihao

    2015-08-01

    Aquatic products are extremely perishable food commodities. Developing methods to keep the freshness of fish represents a major task of the fishery processing industry. Application of Lactic Acid Bacteria (LAB) as food preservative is a novel approach. In the present study, the possibility of using lactic acid bacteria in freshness keeping of tilapia fillets as sashimi was examined. Fish fillets were dipped in Lactobacillus plantarum 1.19 (obtained from China General Microbiological Culture Collection Center) suspension as LAB-treated group. Changes in K-value, APC, sensory properties and microbial flora were analyzed. Results showed that LAB treatment slowed the increase of K-value and APC in the earlier storage, and caused a smooth decrease in sensory score. Gram-negative bacteria dominated during refrigerated storage, with Pseudomonas and Aeromonas being relatively abundant. Lactobacillus plantarum 1.19 had no obvious inhibitory effect against these Gram-negatives. However, Lactobacillus plantarum 1.19 changed the composition of Gram-positive bacteria. No Micrococcus were detected and the proportion of Staphylococcus decreased in the spoiled LAB-treated samples. The period that tilapia fillets could be used as sashimi material extended from 24 h to 48 h after LAB treatment. The potential of using LAB in sashimi processing was confirmed.

  9. Dual-coated lactic acid bacteria: an emerging innovative technology in the field of probiotics.

    Alvarez-Calatayud, Guillermo; Margolles, Abelardo

    2016-01-01

    Probiotics are living micro-organisms that do not naturally have shelf life, and normally are weakly protected against the digestive action of the GI tract. A new dual coating technology has been developed in an effort to maximize survival, that is, to be able to reach the intestine alive and in sufficient numbers to confer the beneficial health effects on the host. Dual-coating of lactic acid bacteria (LAB) is the result of fourth-generation coating technology for the protection of these bacteria at least 100-fold or greater than the uncoated LAB. This innovative technique involves a first pH-dependent protein layer that protects bacteria from gastric acid and bile salt, and a second polysaccharide matrix that protects bacteria from external factors, such as humidity, temperature and pressure, as well as the digestive action during the passage through the GI tract. Dual-coated probiotic formulation is applicable to different therapeutic areas, including irritable bowel syndrome, atopic dermatitis, acute diarrhea, chronic constipation, Helicobacter pylori eradication, and prevention of antibiotic-associated diarrhea. An updated review of the efficacy of doubly coated probiotic strains for improving bacterial survival in the intestinal tract and its consequent clinical benefits in humans is here presented. PMID:26780116

  10. From physiology to systems metabolic engineering for the production of biochemicals by lactic acid bacteria

    Gaspar, Paula; Carvalho, Ana L.; Vinga, Susana;

    2013-01-01

    The lactic acid bacteria (LAB) are a functionally related group of low-GC Gram-positive bacteria known essentially for their roles in bioprocessing of foods and animal feeds. Due to extensive industrial use and enormous economical value, LAB have been intensively studied and a large body of compr...... food fermentations. Here we discuss recent metabolic engineering strategies to improve particular cellular traits of LAB and to design LAB cell factories for the bioproduction of added value chemicals.......The lactic acid bacteria (LAB) are a functionally related group of low-GC Gram-positive bacteria known essentially for their roles in bioprocessing of foods and animal feeds. Due to extensive industrial use and enormous economical value, LAB have been intensively studied and a large body...... of comprehensive data on their metabolism and genetics was generated throughout the years. This knowledge has been instrumental in the implementation of successful applications in the food industry, such as the selection of robust starter cultures with desired phenotypic traits. The advent of genomics, functional...

  11. Breeding of citric acid-producing bacteria by 15 keV N+ ion implantation

    Aspergillus niger strains CK1-16, the bacteria commonly used in industrial production of citric acid, were implanted with 3.10 x 1014 to 2.58 x 1015 ions/cm2 of 15 keV N+ ions. Survival rate of the bacteria at different doses was investigated, and mutagenic effects of the microbe were studied. From the ion-implanted specimens, authors were able to obtain three mutant strains that produce increased yield of citric acid. The 71 hours yield of Mutant Strain 4 hash-8-1 incubated in cassava and corn flour media is 14% higher than the CK1-16 strain, while Mutant Strains 4hash-8-7and 4hash-8-7, incubated in corn flour media are 15.9% and 17.0% higher than the CK1-16 strain, respectively. The results also show that the mutant strains have high genetic stability. (authors)

  12. LACTIC ACID BACTERIA FLORA OF KONYA KUFLU CHEESE: A TRADITIONAL CHEESE FROM KONYA PROVINCE IN TURKEY

    Ziba Guley

    2014-12-01

    Full Text Available The aim of this study was to characterize the lactic acid bacteria flora of mature Konya Kuflu cheese. Konya Kuflu cheese is a traditional blue cheese which is produced from raw milk without starter culture addition and mould growth occurs in uncontrolled conditions during its ripening. Lactic acid bacteria (LAB isolated from 9 mature Konya Kuflu cheese samples were investigated using a combination of conventional biochemical tests, API test kits, and molecular approaches. For some isolates, different results were obtained according to the identification technique. The overall LAB profile of Konya Kuflu cheese samples revealed that Lactobacillus brevis, Lactobacillus paracasei/Lactobacillus casei, Lactobacillus plantarum, Enterococcus faecium, and Enterococcus faecalis are the predominant species. In addition, 1 Pediococcus parvulus and 1 Enterococcus durans were also identified.

  13. Antilisterial activity of lactic acid bacteria isolated from vacuum-packaged brazilian meat and meat products

    Martinis Elaine C.P. De

    2001-01-01

    Full Text Available Twenty samples of Brazilian meat and meat products were screened by the agar overlay method for bacteriocin-producing lactic acid bacteria, using Lactobacillus sake ATCC 15521 as indicator strain. Based on Gram staining, KOH reaction, catalase test and fermentation of 49 carbohydrates (API 50 CH, three out of seven isolates with confirmed antagonist properties were identified as Lactobacillus curvatus, one as Leuconostoc mesenteroides and one as Leuconostoc sp. Two isolates could not be properly identified using these tests. The inhibitors produced by these strains were sensitive to proteases. Inhibition due to lytic bacteriophages was ruled out, so the isolates were classified as bacteriocin-producing lactic acid bacteria. Four of them presented antilisterial activity and a potential application as biopreservatives in meat systems.

  14. Characterization of Lactic Acid Bacteria Isolated from Sauce-type Kimchi.

    Jung, Suk Hee; Park, Joung Whan; Cho, Il Jae; Lee, Nam Keun; Yeo, In-Cheol; Kim, Byung Yong; Kim, Hye Kyung; Hahm, Young Tae

    2012-09-01

    This study was carried out to investigate the isolation and characterization of lactic acid bacteria (LAB) from naturally fermented sauce-type kimchi. Sauce-type kimchi was prepared with fresh, chopped ingredients (Korean cabbage, radish, garlic, ginger, green onion, and red pepper). The two isolated bacteria from sauce-type kimchi were identified as Pediococcus pentosaceus and Lactobacillus brevis by 16S rDNA sequencing and tentatively named Pediococcus sp. IJ-K1 and Lactobacillus sp. IJ-K2, respectively. Pediococcus sp. IJ-K1 was isolated from the early and middle fermentation stages of sauce-type kimchi whereas Lactobacillus sp. IJ-K2 was isolated from the late fermentation stage. The resistance of Pediococcus sp. IJ-K1 and Lactobacillus sp. IJ-K2 to artificial gastric and bile acids led to bacterial survival rates that were 100% and 84.21%, respectively. PMID:24471087

  15. The influence of gene transfer on the lactic acid bacteria evolution

    Višnja Bačun-Družina

    2009-09-01

    Full Text Available In the case of preparing various dairy products, the exploitation of lactic acid bacteria has been essential in the course of past millennia in all known nations. Numerous comparative analyses of gene and genome sequences reveal that the exchange of genetic material within and between bacterial species is far more general and frequent than has previously been thought. Consequently, the horizontal gene transfer between distant species or within the same species is an important factor in the Lactobacillales evolution. Knowledge about the exchange of lactobacillus genetic information through horizontal gene transfer, mobile genetic elements, and its evolution is very important due to characterizations and stability maintenance of autochthonous as well as industrial lactic acid bacteria strains in dairy products that benefit human health.

  16. Effect of oxidoreduction potential on aroma biosynthesis by lactic acid bacteria in nonfat yogurt.

    Martin, F; Cachon, R; Pernin, K; De Coninck, J; Gervais, P; Guichard, E; Cayot, N

    2011-02-01

    The aim of this study was to investigate the effect of oxidoreduction potential (Eh) on the biosynthesis of aroma compounds by lactic acid bacteria in non-fat yogurt. The study was done with yogurts fermented by Lactobacillus bulgaricus and Streptococcus thermophilus. The Eh was modified by the application of different gaseous conditions (air, nitrogen, and nitrogen/hydrogen). Acetaldehyde, dimethyl sulfide, diacetyl, and pentane-2,3-dione, as the major endogenous odorant compounds of yogurt, were chosen as tracers for the biosynthesis of aroma compounds by lactic acid bacteria. Oxidative conditions favored the production of acetaldehyde, dimethyl sulfide, and diketones (diacetyl and pentane-2,3-dione). The Eh of the medium influences aroma production in yogurt by modifying the metabolic pathways of Lb. bulgaricus and Strep. thermophilus. The use of Eh as a control parameter during yogurt production could permit the control of aroma formation. PMID:21257030

  17. Development of growth rate measuring method for intracellular, parasitic acid-fast bacteria using radioisotopes

    To prevent and treat infections diseases caused by pathogenic acid-fast bacteria such as Mycobacterium leprae, Tubercle bacillus, it is important to elucidate the mechanisms of intracellular proliferations of these bacteria. This research project was started to make DNA library using a new constructed shuttle vector. Development of in vitro evaluation method for intracellular proliferation of mycobacterium and its transformed cells was attempted on the basis of Buddemeyer method. This method was able to precisely determine the metabolic activities as low as those in leprae and its modified method using 14C-palmitic acid was highly sensitive and the results were obtainable in a shorter period. The generated CO2 was satisfactorily absorbed into scintillator without using a filter paper. A new culture medium from which arginine, a NO-producing compound was eliminated was used to repress the sterilizing effects of NO, but the metabolic activities of leprae was not enhanced. (M.N.)

  18. Structure of an Extracellular Polysaccharide from a Strain of Lactic Acid Bacteria

    顾笑梅; 马桂荣; 吴厚铭

    2003-01-01

    A new extracellular polysaccharide (EPS-I) isolated and purified from Z222, a strain of Lactic acid bacteria has been investigated. Sugar composition analysis, methylation analysis and 1H NMR and 13C NMR spectroscopy reveal that the EPS-I is composed of a pentasaccharide repeating unit. The sequence of sugar residue was determined by using two-dlmensional NMR spectroscopy, including heteronudear multiple-bond correlation(HMBC) and nuclear overhauser effect spectroscopy (NOESY).

  19. Evolution of Yeasts and Lactic Acid Bacteria During Fermentation and Storage of Bordeaux Wines

    Fleet, G. H.; Lafon-Lafourcade, S.; Ribéreau-Gayon, P.

    1984-01-01

    The levels of yeasts and lactic acid bacteria that naturally developed during the vinification of two red and two white Bordeaux wines were quantitatively examined. Yeasts of the genera Rhodotorula, Pichia, Candida, and Metschnikowia occurred at low levels in freshly extracted grape musts but died off as soon as fermentation commenced. Kloeckera apiculata (Hanseniaspora uvarum), Torulopsis stellata, and Saccharomyces cerevisiae, the dominant yeasts in musts, proliferated to conduct alcoholic ...

  20. Analysis of the lactic acid bacteria microflora in traditional Caucasus cow's milk cheeses

    Terzić-Vidojević Amarela; Nikolić Milica; Veljović Katarina; Tolinački Maja; Busarčević M.; Topisirović L.

    2009-01-01

    A total of 157 lactic acid bacteria (LAB) were isolated from three hand-made cheeses taken from different households in the region of the Caucasus Mountains. The cheeses were manufactured from cow's milk without the addition of a starter culture. The isolates of LAB were characterized by subjecting them to phenotypic and genotypic tests. The results of identification of LAB indicate that the examined cheeses contained 10 species, viz., Lactobacillus plantarum, Lactobacillus paraplantarum, Lac...

  1. Identification and characterization of lactic acid bacteria isolated from artisanal white brined Golija cows’ milk cheeses

    Terzić-Vidojević Amarela; Mihajlović Sanja; Uzelac Gordana; Golić Nataša; Fira Đ.; Kojić M.; Topisirović Lj.

    2014-01-01

    The aim of this study was to identify and characterize the lactic acid bacteria (LAB) of artisanal Golija raw and cooked cows’ milk cheeses traditionally manufactured without the addition of starter culture. A total of 188 Gram-positive and catalase-negative isolates of Golija cheeses were obtained from seven samples of different ripening time. Phenotypebased assays as well as rep-PCR and 16S rDNA sequence analysis were undertaken for all 188 Lstrains. The ...

  2. Comparative analysis of antimicrobial and proteolytic activity of lactic acid bacteria isolated from Zlatar cheese

    Topisirović Ljubiša; Veljović Katarina; Terzić-Vidojević Amarela; Strahinić Ivana; Kojić Milan

    2007-01-01

    Traditional artisan Zlatar cheese belongs to the group of white, semi hard home-made cheeses, which are produced from no pasteurized cow's milk, without addition of any known bacterial starter culture. In total, 253 Gram-positive and catalase negative lactic acid bacteria (LAB) were isolated. Results showed that 70 out of 253 analyzed isolates produced antimicrobial compounds known as bacteriocins. Most isolates from genera Lactococcus and Enterococcus, and isolates belonging to ...

  3. Dominant lactic acid bacteria in artisanal Pirot cheeses of different ripening period

    Terzić-Vidojević Amarela; Lozo Jelena; Topisirović Ljubiša

    2009-01-01

    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 b...

  4. Production of freeze-dried lactic acid bacteria starter culture for cassava fermentation into gari.

    Yao, Amenan Anastasie; Dortu, Carine; Egounlety, Moutairu; Pinto, Cristina; Vinodh, A. Edward; Huch, Melanie; Franz, Charles M. A. P.; Holzapfel, Willhelm; Mbugua, Samuel; Mengu, Moses; Thonart, Philippe

    2009-01-01

    Sixteen lactic acid bacteria, eight Lactobacillus plantarum, three L. pentosus, 2 Weissella paramesenteroides, two L. fermemtum and one Leuconostoc mesenteroides ssp. mesenteroides were previously isolated from cassava fermentation and selected on the basis of their biochemical properties with a view to selecting appropriate starter cultures during cassava fermentation for gari production. In this study, the potential of these pre-selected strains as suitable freeze-dried cultures was eval...

  5. Characteristics of Some Lactic Acid Bacteria Used as Starter Cultures in Dry Sausage Production

    Nordal, John; Slinde, Erik

    1980-01-01

    The fermentation characteristics of two commercial (Duploferment 66 and Saga II) and five Norwegian lactic acid bacteria used in dry sausage production were compared with those of Lactobacillus plantarum ATCC 8014. The Norwegian strains lacked the ability to ferment mannitol, sorbitol, lactose, and d-(+)-raffinose and grew at 8 but not at 42°C, in contrast to the ATCC culture and the two commercial strains. The lactate dehydrogenase activity of the Norwegian strains was not stimulated by pyru...

  6. In Vitro Properties of Potential Probiotic Indigenous Lactic Acid Bacteria Originating from Traditional Pickles

    Mehmet Tokatlı; Gökşen Gülgör; Simel Bağder Elmacı; Nurdan Arslankoz İşleyen; Filiz Özçelik

    2015-01-01

    The suitable properties of potential probiotic lactic acid bacteria (LAB) strains (preselected among 153 strains on the basis of their potential technological properties) isolated from traditional Çubuk pickles were examined in vitro. For this purpose, these strains (21 Lactobacillus plantarum, 11 Pediococcus ethanolidurans, and 7 Lactobacillus brevis) were tested for the ability to survive at pH 2.5, resistance to bile salts, viability in the presence of pepsin-pancreatin, ability to deconju...

  7. Inhibition of mycotoxin-producing Aspergillus nomius vsc 23 by lactic acid bacteria and Saccharomyces cerevisiae

    Muñoz, R; Arena, M.E.; Silva, J.; S.N. González

    2010-01-01

    The effect of different fermenting microorganisms on growth of a mycotoxin- producing Aspergillus nomius was assayed. Two lactic acid bacteria, Lactobacillus fermentum and Lactobacillus rhamnosus, and Saccharomyces cerevisiae, all of which are widely used in fermentation and preservation of food, were assayed on their fungus inhibitory properties. Assays were carried out by simultaneous inoculation of one of the possible inhibiting microorganisms and the fungus or subsequent inoculation of on...

  8. Lactic Acid and Probiotic Bacteria from Fermented and Probiotic Dairy Products

    B.K.L. Karna; Virginia L. Barraquio; O. C. Emata

    2007-01-01

    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 ...

  9. Molecular characterization of lactic acid bacteria recovered from natural fermentation of beet root and carrot Kanji

    Kingston, J. J.; Radhika, M.; Roshini, P. T.; Raksha, M. A.; H.S. Murali; Batra, H. V.

    2010-01-01

    The lactic acid bacteria (LAB) play an important role in the fermentation of vegetables to improve nutritive value, palatability, acceptability, microbial quality and shelf life of the fermented produce. The LAB associated with beetroot and carrot fermentation were identified and characterized using different molecular tools. Amplified ribosomal DNA restriction analysis (ARDRA) provided similar DNA profile for the 16 LAB strains isolated from beetroot and carrot fermentation while repetitive ...

  10. Acetic acid bacteria genomes reveal functional traits for adaptation to life in insect guts

    B. Chouaia; Gaiarsa, S.; Crotti, E.; Comandatore, F.; Degli Esposti, M.; I. RICCI; Alma, A.; Favia, G.; Bandi, C.; D. Daffonchio

    2014-01-01

    Acetic acid bacteria (AAB) live in sugar rich environments, including food matrices, plant tissues, and the gut of sugar-feeding insects. By comparing the newly sequenced genomes of Asaia platycodi and Saccharibacter sp., symbionts of Anopheles stephensi and Apis mellifera, respectively, with those of 14 other AAB, we provide a genomic view of the evolutionary pattern of this bacterial group and clues on traits that explain the success of AAB as insect symbionts. A specific pre-adaptive trait...

  11. Bioactive Molecules Released in Food by Lactic Acid Bacteria: Encrypted Peptides and Biogenic Amines

    Pessione, Enrica; Cirrincione, Simona

    2016-01-01

    Lactic acid bacteria (LAB) can produce a huge amount of bioactive compounds. Since their elective habitat is food, especially dairy but also vegetal food, it is frequent to find bioactive molecules in fermented products. Sometimes these compounds can have adverse effects on human health such as biogenic amines (tyramine and histamine), causing allergies, hypertensive crises, and headache. However, some LAB products also display benefits for the consumers. In the present review article, the ma...

  12. Mechanism of gallic acid biosynthesis in bacteria (Escherichia coli) and walnut (Juglans regia)

    Muir, Ryann M.; Ibáñez, Ana M.; Uratsu, Sandra L; Ingham, Elizabeth S.; Leslie, Charles A; McGranahan, Gale H.; Batra, Neelu; Goyal, Sham; Joseph, Jorly; Jemmis, Eluvathingal D; Dandekar, Abhaya M

    2011-01-01

    Gallic acid (GA), a key intermediate in the synthesis of plant hydrolysable tannins, is also a primary anti-inflammatory, cardio-protective agent found in wine, tea, and cocoa. In this publication, we reveal the identity of a gene and encoded protein essential for GA synthesis. Although it has long been recognized that plants, bacteria, and fungi synthesize and accumulate GA, the pathway leading to its synthesis was largely unknown. Here we provide evidence that shikimate dehydrogenase (SDH),...

  13. The influence of gene transfer on the lactic acid bacteria evolution

    Višnja Bačun-Družina; Jasna Mrvčić; Ana Butorac; Krešimir Gjuračić

    2009-01-01

    In the case of preparing various dairy products, the exploitation of lactic acid bacteria has been essential in the course of past millennia in all known nations. Numerous comparative analyses of gene and genome sequences reveal that the exchange of genetic material within and between bacterial species is far more general and frequent than has previously been thought. Consequently, the horizontal gene transfer between distant species or within the same species is an important factor in the La...

  14. The influence of a cryoprotective medium containing glycerol on the lyophilization of lactic acid bacteria (NOTE)

    JOSIP BARAS; SUZANA DIMITRIJEVIC-BRANKOVIC; ALEKSANDAR KODZIC; NADA TRSIC-MILANOVIC

    2001-01-01

    The aims of liophilization (freeze-drying) of lactic acid bacteria are to preserve pure cultures or to prepare starters for the dairy industry. In both cases, the choice of the cryoprotectant is very important. In this work, samples of Bifidobacterium breve A71 and Bifidobacterium bifidum BbTD were freeze-dried in a new cryoprotective medium containing lactose, gelatine and glycerol (medium B). The reference medium contained saccharose, gelatine and skim milk (medium A). Before liophilization...

  15. Oxalate-Degrading Capacities of Gastrointestinal Lactic Acid Bacteria and Urinary Tract Stone Formation

    Mohammad Kargar; Rouhi Afkari; Sadegh Ghorbani-Dalini

    2013-01-01

    Background: Calcium oxalate is one the most significant causes of human kidney stones. Increasing oxalate uptake results in increased urinary oxalate. Elevated urinary oxalate is one the most important causes of kidney stone formation. This study aims to evaluate oxalate-degrading capacity of lactic acid bacteria and its impact on incidence of kidney stone.Materials and Methods: This case-control study was conducted on serum, urinary, and fecal samples. The research population included a tota...

  16. Lactic acid bacteria against post-harvest moulds and ochratoxin A isolated from stored wheat

    Belkacem-Hanfi, N.; Fhoula, I.; Semmar, N.; Guesmi, A.; Perraud Gaime, Isabelle; Ouzari, H. I.; A. Boudabous; Roussos, Sevastianos

    2014-01-01

    A total of 54 lactic acid bacteria (LAB) were isolated from stored wheat samples sourced from grain silos in North Tunisia. Fifteen representative isolates were identified by 16S rDNA sequencing as Pediococcus pentosaceus, Lactobacillus plantarum, Lactobacillus graminis, Lactobacillus coryniformis and Weissella cibaria. These isolates were screened for antifungal activity in dual culture agar plate assay against eight post-harvest moulds (Penicillium expansum, Penicillium chrysogenum, Penicil...

  17. PROTEOLYTIC AND FIBRINOLYTIC ACTIVITIES OF HALOPHILIC LACTIC ACID BACTERIA FROM TWO INDONESIAN FERMENTED FOODS

    Prihanto, Asep A.; Darius; Muhamad Firdaus

    2013-01-01

    Exploration of fermented foods as sources of fibrinolytic enzymes is increased in the last decades. Terasi and Jambal roti is Indonesian traditional fermented fish products, which were famous in Java Island. Both are important products in Indonesian dishes, especially in Java. Investigation on halophilic lactic acid bacteria using MRS and M-17 agar obtained seventy four isolated strains. Their proteolytic and fibrinolytic activities were determined using skim milk agar and plasminogen-free fi...

  18. Efficacy of Lactic Acid Bacteria (LAB) supplement in management of constipation among nursing home residents

    Kim Jung; Kim Mi; Lee Do; Jang Seok; Baek Eun; An Hyang; Lee Kang; Park Jong; Ha Nam

    2010-01-01

    Abstract Background Constipation is a significant problem in the elderly, specifically nursing home and/or extended-care facility residents are reported to suffer from constipation. Lactic acid bacteria (LAB) are beneficial probiotic organisms that contribute to improved nutrition, microbial balance, and immuno-enhancement of the intestinal tract, as well as diarrhea and constipation effect. The objective of this study was to investigate the efficacy of this LAB supplement in the management o...

  19. Production of bacteriocin-like substances by lactic acid bacteria isolated from regional ovine cheese

    Cássia Regina Nespolo; Adriano Brandelli

    2010-01-01

    Lactic acid bacteria (LAB) were isolated from ovine milk and cheeses manufactured in the South Region of Brazil. Among 112 bacterial isolates investigated, 59 were chosen through a screening for LAB. Among these 59 strains of LAB, 21% showed antimicrobial, proteolytic and lipolytic activities. Based on this screening, Lactobacillus plantarum LCN 17 and Lactobacillus rhamnosus LCN 43 were selected and tested for the production of bacteriocin-like substances (BLS). The BLS produced by both isol...

  20. Lactic acid bacteria affect serum cholesterol levels, harmful fecal enzyme activity, and fecal water content

    Chung Myung; Shin Hea; Lee Kyung; Kim Mi; Baek Eun; Jang Seok; Lee Do; Kim Jin; Lee Kang; Ha Nam

    2009-01-01

    Abstract Background Lactic acid bacteria (LAB) are beneficial probiotic organisms that contribute to improved nutrition, microbial balance, and immuno-enhancement of the intestinal tract, as well as lower cholesterol. Although present in many foods, most trials have been in spreads or dairy products. Here we tested whether Bifidobacteria isolates could lower cholesterol, inhibit harmful enzyme activities, and control fecal water content. Methods In vitro culture experiments were performed to ...

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

    Esmeray Küley; Fatih Özogul; Esra Balikçi; Mustafa Durmus; Deniz Ayas

    2013-01-01

    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 obser...

  2. Screening of biogenic amine production by lactic acid bacteria isolated from grape musts and wine

    Moreno-Arribas, M. Victoria; Polo, María Carmen; Jorganes, Felisa; Muñoz, Rosario

    2003-01-01

    The potential to produce the biogenic amines tyramine, histamine and putrescine, was investigated for lactic acid bacteria (LAB) of various origin, including commercial malolactic starter cultures, type strains and 78 strains isolated from Spanish grape must and wine. The presence of biogenic amines in a decarboxylase synthetic broth was determined by reverse-phase high performance liquid chromatography (RP-HPLC). Tyramine was the main amine formed by the LAB strains investigated. ...

  3. Lactic acid bacteria contribution to gut microbiota complexity: lights and shadows

    Pessione, Enrica

    2012-01-01

    Lactic Acid Bacteria (LAB) are ancient organisms that cannot biosynthesize functional cytochromes, and cannot get ATP from respiration. Besides sugar fermentation, they evolved electrogenic decarboxylations and ATP-forming deiminations. The right balance between sugar fermentation and decarboxylation/deimination ensures buffered environments thus enabling LAB to survive in human gastric trait and colonize gut. A complex molecular cross-talk between LAB and host exists. LAB moonlight proteins ...

  4. Characterization and in vitro probiotic evaluation of lactic acid bacteria isolated from idli batter

    Iyer, Bharti K.; Singhal, Rekha S.; Ananthanarayan, Laxmi

    2011-01-01

    An Indian traditional fermented food, idli batter, was used as a source for isolation of lactic acid bacteria (LAB). A total of 15 LAB strains were isolated on the basis of their Gram nature and catalase activity. Of these, one lactobacilli strain and one lactococci strain which showed antimicrobial activity were identified using biochemical characterization, sugar utilization and molecular sequencing. The microbes, labeled as IB-1 (Lactobacillus plantarum) and IB-2 (Lactococcus lactis) were ...

  5. Investigation of immune-modulatory properties of non-digestible oligosaccharides and lactic acid bacteria

    Lehmann, Sarah

    2015-01-01

    This work characterizes immune-modulatory properties of non-digestible oligosaccharides (NDO) mimicking the natural distribution of NDO in human breast milk and different lactic acid bacteria (LAB) like Lactobacilli or Bifidobacteria in human immune cells. The obtained results indicate anti-inflammatory and direct, microbiota independent, immune-regulatory properties of NDO in dendritic cells and T cells, as well as specific immune-modulatory capacities of the tested LAB in an in vitro co-cul...

  6. Cytotoxic effects of various lactic acid bacteria on Caco-2 cells

    ER, Sevda; Koparal, Ayşe Tansu; Merih KIVANÇ

    2015-01-01

    Probiotics are live microbial food supplements that can be considered a functional food. They benefit the health of a host animal by maintaining their intestinal microbial balance. Most probiotic microorganisms are lactic acid bacteria (LAB) such as Lactobacillus spp., Bifidobacterium spp., and Enterococcus spp. LAB have been reported to possess certain anticancer properties. The vast majority of studies on their anticancer effects have dealt with colorectal cancers, although there have also ...

  7. Molecular characterization of lactic acid bacteria isolated from industrially fermented Greek table olives

    Doulgeraki, Agapi; Pramateftaki, Paraskevi; Argyri, Anthoula; Nychas, George John; Tassou, Chrysoula; Panagou, Efstathios

    2012-01-01

    A total of 145 lactic acid bacteria (LAB) isolates have been recovered from fermented table olives and brine and characterized at strain level with molecular tools. Pulsed-Field Gel Electrophoresis (PFGE) of ApaI macrorestriction fragments was applied for strain differentiation. Species differentiation was based either on Denaturing Gradient Gel Electrophoresis (PCR-DGGE) (black olives) or on restriction analysis of the amplified 16S rRNA gene (PCR-ARDRA) (brine and green olives). Species ide...

  8. Bacteriocins from lactic acid bacteria: purification, properties and use as biopreservatives

    José Luis Parada; Carolina Ricoy Caron; Adriane Bianchi P. Medeiros; Carlos Ricardo Soccol

    2007-01-01

    Biopreservation systems in foods are of increasing interest for industry and consumers. Bacteriocinogenic lactic acid bacteria and/or their isolated bacteriocins are considered safe additives (GRAS), useful to control the frequent development of pathogens and spoiling microorganisms in foods and feed. The spreading of bacterial antibiotic resistance and the demand for products with fewer chemicals create the necessity of exploring new alternatives, in order to reduce the abusive use of therap...

  9. Selective removal of transition metals from acidic mine waters by novel consortia of acidophilic sulfidogenic bacteria

    Ňancucheo, Ivan; Johnson, D. Barrie

    2011-01-01

    Summary Two continuous‐flow bench‐scale bioreactor systems populated by mixed communities of acidophilic sulfate‐reducing bacteria were constructed and tested for their abilities to promote the selective precipitation of transition metals (as sulfides) present in synthetic mine waters, using glycerol as electron donor. The objective with the first system (selective precipitation of copper from acidic mine water containing a variety of soluble metals) was achieved by maintaining a bioreactor p...

  10. Enzymatic hydrolysates from food wastewater as a source of peptones for lactic acid bacteria productions

    Vázquez, José Antonio; Murado García, Miguel Anxo

    2008-01-01

    A diverse group of peptones obtained by enzymatic hydrolysis of wastewater from the industrial processing of octopus showed their effectiveness to promote the growth of lactic acid bacteria (LAB) and the production of bacteriocins. The highest nisin formation by Lactococcus lactis was reached using peptones from papain hydrolysis for 24 h (enzyme concentration: 1.25 mg papain/g protein). On the other hand, the highest pediocin production by Pediococcus acidilactici was obtained with peptones ...

  11. Rapid In Situ Assay for Indoleacetic Acid Production by Bacteria Immobilized on a Nitrocellulose Membrane

    Bric, John M.; Richard M Bostock; Silverstone, Sara E.

    1991-01-01

    We have developed a new assay that differentiates between indoleacetic acid (IAA)-producing and -nonproducing bacteria on a colony plate lift. Medium supplemented with 5 mM L-tryptophan is inoculated with isolates of interest, overlaid with a nitrocellulose membrane, and then incubated until bacterial colonies reach 1 to 2 mm in diameter. The membrane is removed to a filter paper saturated with Salkowski reagent and incubated until distinct red haloes form around the colonies. The colorimetri...

  12. ANTI – SHIGELLA DYSENTERIAE ACTIVITY BY PROBIOTIC LACTIC ACID BACTERIA (PEDIOCOCCUS PENTOSACEUS); AN IN VITRO STUDY

    Srividya D.; Chandra Prakash S. V.; Shylaja M. Dharmesh; Renu Agrawal

    2015-01-01

    Shigellosis caused by Shigella is prevalent throughout the world with approximately 164.7 million cases, of which 163.2 million are in developing countries as per the World Health Organization report. In the current study the effect of a known Probiotic Lactic acid Bacteria (PLB) Pediococcus pentosaceus, a previously reported strain of PLB from our laboratory on gastroenteric pathogen – Shigella dysenteriae was studied and its mode of action was established. In agar diffusion tests PLB lysate...

  13. Fresh-Cut Pineapple as a New Carrier of Probiotic Lactic Acid Bacteria

    2014-01-01

    Due to the increasing interest for healthy foods, the feasibility of using fresh-cut fruits to vehicle probiotic microorganisms is arising scientific interest. With this aim, the survival of probiotic lactic acid bacteria, belonging to Lactobacillus plantarum and Lactobacillus fermentum species, was monitored on artificially inoculated pineapple pieces throughout storage. The main nutritional, physicochemical, and sensorial parameters of minimally processed pineapples were monitored. Finally,...

  14. Natural populations of lactic acid bacteria in douchi from Yunnan Province, China*

    Liu, Chen-jian; Gong, Fu-ming; Li, Xiao-ran; Li, Hai-Yan; Zhang, Zhong-Hua; Feng, Yue; Nagano, Hiroko

    2012-01-01

    This research was aimed at isolating and identifying the predominant lactic acid bacteria (LAB) in the traditional Chinese salt-fermented soybean food, douchi, from Yunnan, China. The predominant LAB present were isolated and identified by conventional culture-dependent methods combined with molecular biological methods. Two hundred and sixty isolates were obtained from thirty kinds of traditional fermented douchi from six cities and counties in Yunnan, and those strains were divided into twe...

  15. In vitro screening of probiotic lactic acid bacteria and prebiotic glucooligosaccharides to select effective synbiotics

    Grimoud, Julien; Durand, Henri; Courtin, Céline; Monsan, Pierre; Ouarné, Françoise; Theodorou, Vassilia; Roques, Christine

    2010-01-01

    Probiotics and prebiotics have been demonstrated to positively modulate the intestinal microflora and could promote host health. Although some studies have been performed on combinations of probiotics and prebiotics, constituting synbiotics, results on the synergistic effects tend to be discordant in the published works. The first aim of our study was to screen some lactic acid bacteria on the basis of probiotic characteristics (resistance to intestinal conditions, inhibition of pathogenic st...

  16. Stochastic modelling of Listeria monocytogenes single cell growth in cottage cheese with mesophilic lactic acid bacteria from aroma producing cultures

    Østergaard, Nina Bjerre; Christiansen, Lasse Engbo; Dalgaard, Paw

    2015-01-01

    A stochastic model was developed for simultaneous growth of low numbers of Listeria monocytogenes and populations of lactic acid bacteria from the aroma producing cultures applied in cottage cheese. During more than two years, different batches of cottage cheese with aroma culture were analysed for...... pH, lactic acid concentration and initial concentration of lactic acid bacteria. These data and bootstrap sampling were used to represent product variability in the stochastic model. Lag time data were estimated from observed growth data (lactic acid bacteria) and from literature on L. monocytogenes....... 2014. Modelling the effect of lactic acid bacteria from starter- and aroma culture on growth of Listeria monocytogenes in cottage cheese. International Journal of Food Microbiology. 188, 15-25]. Growth of L. monocytogenes single cells, using lag time distributions corresponding to three different...

  17. Ethanol Production by Selected Intestinal Microorganisms and Lactic Acid Bacteria Growing under Different Nutritional Conditions.

    Elshaghabee, Fouad M F; Bockelmann, Wilhelm; Meske, Diana; de Vrese, Michael; Walte, Hans-Georg; Schrezenmeir, Juergen; Heller, Knut J

    2016-01-01

    To gain some specific insight into the roles microorganisms might play in non-alcoholic fatty liver disease (NAFLD), some intestinal and lactic acid bacteria and one yeast (Anaerostipes caccae, Bacteroides thetaiotaomicron, Bifidobacterium longum, Enterococcus fecalis, Escherichia coli, Lactobacillus acidophilus, Lactobacillus fermentum, Lactobacillus plantarum, Weissella confusa, Saccharomyces cerevisiae) were characterized by high performance liquid chromatography for production of ethanol when grown on different carbohydrates: hexoses (glucose and fructose), pentoses (arabinose and ribose), disaccharides (lactose and lactulose), and inulin. Highest amounts of ethanol were produced by S. cerevisiae, L. fermentum, and W. confusa on glucose and by S. cerevisiae and W. confusa on fructose. Due to mannitol-dehydrogenase expressed in L. fermentum, ethanol production on fructose was significantly (P fermentative, mannitol-dehydrogenase negative lactic acid bacterium, may promote NAFLD through ethanol produced from sugar fermentation, while other intestinal bacteria and homo- and hetero-fermentative but mannitol-dehydrogenase positive lactic acid bacteria may not promote NAFLD. Also, our studies indicate that dietary factors interfering with gastrointestinal microbiota and microbial metabolism may be important in preventing or promoting NAFLD. PMID:26858714

  18. Immune Modulation Capability of Exopolysaccharides Synthesised by Lactic Acid Bacteria and Bifidobacteria.

    Hidalgo-Cantabrana, Claudio; López, Patricia; Gueimonde, Miguel; de Los Reyes-Gavilán, Clara G; Suárez, Ana; Margolles, Abelardo; Ruas-Madiedo, Patricia

    2012-12-01

    During recent years, the exopolysaccharides (EPS) produced by some strains of lactic acid bacteria and bifidobacteria have attracted the attention of researchers, mainly due to their potential technological applications. However, more recently, it has been observed that some of these EPS present immunomodulatory properties, which suggest a potential effect on human health. Whereas EPS from lactic acid bacteria have been studied in some detail, those of bifidobacteria largely remain uncharacterized in spite of the ubiquity of EPS genes in Bifidobacterium genomes. In this review, we have analysed the data collected in the literature about the potential immune-modulating capability of EPS produced by lactic acid bacteria and bifidobacteria. From this data analysis, as well as from results obtained in our group, a hypothesis relating the physicochemical characteristics of EPS with their immune modulation capability was highlighted. We propose that EPS having negative charge and/or small size (molecular weight) are able to act as mild stimulators of immune cells, whereas those polymers non-charged and with a large size present a suppressive profile. PMID:26782182

  19. Assessment of Antifungal Activity of Lactic Acid Bacteria Strains Against Bread Spoilage Fungus Aspergillus ochraceus

    Adrian Matei

    2015-11-01

    Full Text Available Lactic acid bacteria (LAB are generally recognized as safe and can be used against fungi that contaminate various food commodities. The aim of the research was to select LAB strains with high antifungal activity for the biocontrol of Aspergillus ochraceus. The antifungal activity of eight strains of lactic acid bacteria has been evaluated by overlay assay method against the spoilage fungus, Aspergillus ochraceus isolated from white bread. The antifungal effect was assessed by co-cultivation of lactic acid bacteria strains and Aspergillus ochraceus in liquid media and mycelium growth inhibition was monitored for over 14 days. The LAB strains Lpl, LAB 43 and LAB 13 presented intense antifungal activity with large inhibition zones of fungal growth and sporulation, but smaller for Lpa and LAB 15 strains. Total inhibition of mycelia growth was induced by the strains LAB 43, LAB 13 and Lpa. The strains LAB 15 and LAB 35 had a moderate inhibition activity on the mycelia growth. The results of this study demonstrated the antifungal activity of several LAB strains by overlay assay and by co-cultivation method. Therefore, it was confirmed the inhibitory effect of the strains LAB 43 and LAB 13 against Aspergillus ochraceus. The experiment revealed that these LAB strains could be further used as biocontrol agents.

  20. Taxonomic homogeneity of a salt-tolerant lactic acid bacteria isolated from shoyu mash.

    Hanagata, Hiroshi; Shida, Osamu; Takagi, Hiroaki

    2003-04-01

    Forty-seven salt-tolerant lactic acid bacteria, which had been isolated from different places and grown in 15% NaCl, were examined to assess their taxonomic heterogeneity. Among the isolates, 42 were isolated from shoyu mash during the acid fermentation phase, 2 were from miso and 3 were from anchovy pickles. All isolates were identified as Tetragenococcus halophilus on the basis of DNA relatedness values. We further examined 102 phenotypic characteristics of them. The isolates exhibited differences in only 16, supporting the conclusion obtained from the DNA relatedness analysis. PMID:12833212

  1. SELECTED PROPERTIES OF LACTIC ACID BACTERIA ISOLATED FROM RAW COW'S MILK

    Miroslav Kročko

    2012-02-01

    Full Text Available Normal 0 21 false false false MicrosoftInternetExplorer4 For the identification of lactic acid bacteria derived from raw cow's milk, 151 colonies were isolated. The grow conditions of lactic acid bacteria were at temperature 37 °C for 3 days on MRS medium. Based on microscopical preparation, negative catalase and Gram-positive test were 81 isolates confirmed as genus Lactobacillus. Out of these, 9 isolates were evaluated for acidifying activity in UHT milk at 25 °C, 30 °C and 37 °C at regular intervals during 24 hours. The average count of NSLAB lactobacilli in raw cow's milk reached the value 1.54.104 KTJ.ml-1. It was found that all tested strains of lactobacilli did not cause significant changes of titratable acidity in milk at 25 °C and 30 °C. Only one strain significantly improved the titratable acidity of milk at 37 °C after 24 hours. The acidity reached the value from 7.5 °SH to 41.9 °SH. This strain was confirmed by PCR method as Lactobacillus helveticus.doi:10.5219/177

  2. Fermentation of Prefermented and Extruded Rice Flour by Lactic Acid Bacteria from Sikhae

    Lee, C. H.; Min, K. C.; Souane, M.;

    1992-01-01

    decreased in the same substrates. The final pH of the cereal lactic beverage was in the range of 3.4 - 4.1, L. mesenteroides(sikhae) had relatively higher pH compared to other lactic acid bacteria. L. mesenteroides(sikhae) produced apple juice-like flavor, while L. plantarum, L. casei and L. lactis yielded......The acid- and flavor-forming properties of Lactobacillus plantarum and Leuconostoc mesenteroides isolated from Sikhae, a Korean traditional lactic acid fermented fish product, were examined and compared to those of Lactobacillus casei and Lactococcus lactis subsp. diacetylactis DRC3. The effects of...... prefermentation of rice flour in solid-state with Bacillus laevolacticus and Saccharomyces cerevisiae, extrusion cooking and addition of soymilk as the substrate of lactic acid fermentation were tested. Extrusion cooking and prefermentation of rice increased the soluble solid and sugar contents before malt...

  3. Study of Lactic Acid Bacteria Community From Raw Milk of Iranian One Humped Camel and Evaluation of Their Probiotic Properties

    Davati, Nafiseh; Tabatabaee Yazdi, Farideh; Zibaee, Saeed; Shahidi, Fakhri; Edalatian, Mohammad Reza

    2015-01-01

    Background: Camel milk is amongst valuable food sources in Iran. On the other hand, due to the presence of probiotic bacteria and bacteriocin producers in camel milk, probiotic bacteria can be isolated and identified from this food product. Objectives: The objectives of the present research were the isolation and molecular identification of lactic acid bacteria from camel milk and evaluation of their probiotic properties. Materials and Methods: A total of ten samples of camel milk were collec...

  4. Antimicrobial Potentials of Lactic Acid Bacteria Isolated From a Nigerian Menstruating Woman

    Funmilola Abidemi Ayeni

    2013-06-01

    Full Text Available ABSTRACT Background: Racial differences affect the composition of lactic acid bacteria (LAB in women’s vagina. However, the bacteria present in women’s vagina exert protective effect against invading uropathogens through production of several inhibitory compounds. The LAB composition of the vagina of a menstruating Nigerian woman was examined to detect any difference between the subject’s vaginal LAB flora and reported cases of women from western world and to investigate the antimicrobial activities of these lactic acid bacteria against potential uropathogens and enteropathogens with analysis of possible compounds that may be responsible for inhibition. Methods: Informed consent was obtained from the subject. LAB were identified by partially sequencing the 16S rRNA gene. The organic acids were detected through High Performance Liquid Chromatography (HPLC while the volatile compounds were detected by gas chromatography. The hydrogen peroxide production was assayed through enzymatic reactions. Results: Enterococcus faecalis FAA025 and Streptococcus equines FAA026 were the only bacterial strains isolated. The two LAB strains inhibited the growth of all tested uropathogens and enteropathogens to remarkable degree. Both strains produced high quantities of lactic acid while high quantities of hydrogen peroxide, acetic acid and ethanol were only observed in Streptococcus equines FAA026. Conclusions: The results of this study suggest that in spite of absence of lactobacilli during menstruation in the subject, other LAB present (Enterococcus faecalis FAA025 and Streptococcus equines FAA026 can exert protective effects against invading uropathogens. Also, the LAB composition of the Nigerian woman is similar to her counterparts in the West. [TAF Prev Med Bull 2013; 12(3.000: 283-290

  5. Plant-based Paste Fermented by Lactic Acid Bacteria and Yeast: Functional Analysis and Possibility of Application to Functional Foods

    Shinsuke Kuwaki; Nobuyoshi Nakajima; Hidehiko Tanaka; Kohji Ishihara

    2012-01-01

    A plant-based paste fermented by lactic acid bacteria and yeast (fermented paste) was made from various plant materials. The paste was made of fermented food by applying traditional food-preservation techniques, that is, fermentation and sugaring. The fermented paste contained major nutrients (carbohydrates, proteins, and lipids), 18 kinds of amino acids, and vitamins (vitamin A, B1, B2, B6, B12, E, K, niacin, biotin, pantothenic acid, and folic acid). It contained five kinds of organic acids...

  6. Ten years of subproteome investigations in lactic acid bacteria: A key for food starter and probiotic typing

    Mangiapane, E.; Mazzoli, R.; Pessione, A.;

    2015-01-01

    in bacteria, chiefly lactic acid bacteria. Production of desired and undesired metabolites, differences between strains belonging to same species but isolated from different ecological niches, the effect of cryoprotectants on survival to lyophilization as well as the adhesive capability of strains, were...

  7. Naphthenic acid extraction and characterization from crude oils and naphthenate field deposits revisited

    Ahmed, M.M.; Sorbie, K.S. [Heriot-Watt Univ., Edinburgh, Scotland (United Kingdom). Inst. of Petroleum Engineering

    2008-07-01

    Crude oil with high total acid number (TAN) often results in the formation of either sodium emulsion or calcium naphthenate deposits. The formation of calcium naphthenate during production operations is creating flow assurance problems for the oil industry. Therefore, it is important to extract and characterize the different types of acids from crude oils and naphthenate field deposits. There has been much discussion in the literature about the discovery and quantification of higher molecular weight acids in naphthenate field deposits, referred to as ARN acids. Field naphthenate deposits from 2 different fields in Norway (X and HD) were used in this study for the naphthenic acid extraction using 3 different methods. The extracted naphthenic acids were characterized using electrospray mass spectrometry (ESMS) and atmospheric pressure chemical ionization mass spectrometry (APCI-MS). The ESMS spectra obtained from field X extract revealed the presence of lower molecular weight acids species only, without any presence of ARN acids. However, the extract from field HD had a broad range of lower molecular weight acids and ARN acid species. APCI-MS results revealed an enhanced ARN acids species from all the spectra with some indication of multimers. This paper also discussed the acid-IER extraction technique used on the crude oils from these fields.

  8. ISOLATION AND IDENTIFICATION OF LACTIC ACID PRODUCING BACTERIA FROM CAMEL MILK

    Toqeer Ahmad, Rashida Kanwal, Izhar Hussain Athar1, Najam Ayub

    2002-03-01

    Full Text Available Lactic acid bacteria (LAB were isolated from camel milk by culturing the camel milk on specific media and pure culture was obtained by sub culturing. Purification of culture was confirmed by Gram's staining and identified by different bio-chemical tests. Camel milk contains lactic acid producing bacteria including Strpptococci such as S. cremoris and S. lactis and Lactobacilli such as L. acidophilus L. acidophilus grows more rapidly in camel milk than others as its growth is supported by camel milk. A variety of food can be preserved by lactic acid fermentation, so starter culture was prepared from strains which were isolated from camel milk. Camel and buffalo's milk cheese was prepared by using starter culture. The strains isolated from camel milk were best for acid production and can coagulate the milk in less lime. Camel milk cheese was prepared and compared with buffalo's milk cheese. It is concluded that cheese can be prepared successfully from camel milk and better results can be obtained by coagulating milk with starter culture.

  9. Population dynamics of mixed cultures of yeast and lactic acid bacteria in cider conditions

    Leila Roseli Dierings

    2013-10-01

    Full Text Available The objective of this work was to study the malolactic bioconversion in low acidity cider, according Brazilian conditions. The apple must was inoculated with Saccharomyces cerevisiae or S. cerevisiae with Oenococcus oeni. The control contained the indigenous microorganisms. Fermentation assays were carried out with clarified apple must from the Gala variety. At the beginning of fermentation, there was a fast growth of the non-Saccharomyces yeast population. Competitive inhibition occurred in all the assays, either with inoculated or indigenous populations of the yeast. The lactic acid bacteria count was ca. 1.41·10²CFU/mL at the beginning and 10(6CFU/mL after yeast cells autolysis. The lactic bacteria O. oeni reached the highest population (10(7CFU/mL when added to the apple must after the decline of the yeast. The malic acid was totally consumed during the alcoholic fermentation period (80.0 to 95.5 % and lactic acid was still synthesized during the 35 days of malolactic fermentation. These results could be important in order to achieve a high quality brut, or sec cider obtained from the dessert apple must.

  10. Antimicrobial resistance of coagulase-negative staphylococci and lactic acid bacteria from industrially produced dairy products

    Nevijo Zdolec

    2013-03-01

    Full Text Available In this research, the susceptibility to clindamycin, tetracycline, amikacin, amoxicillin + clavulanic acid, enrofloxacine, vancomycin, trimethoprim + sulphametoxazol, tobramycin, chloramphenicol, ciprofloxacin, erythromycin, penicillin and trimethoprim was tested in coagulase-negative staphylococci (n=78 and lactic acid bacteria (n=30 by means of disk diffusion test and E-test. The isolates were collected from soft and hard cheeses, butter and brine. All isolates of coagulase-negative staphylococci were susceptible to clindamycin, amikacin, amoxicillin + clavulanic acid, enrofloxacine, vancomycin, chloramphenicol and ciprofloxacin according to CLSI breakpoints. A total of 30 staphylococci isolates (38.46 % were resistant to erythromycin, 18 to penicillin (23.07 %, 4 to tetracycline (5.12 %, and one isolate to trimethoprim, tobramicin and trimethoprim + sulphametoxazol (1.28 %. Among 78 tested staphylococci, 35 of them were resistant to at least one antimicrobial substance (44.87 %. The rate of resistant isolates of different soft cheese types ranged from 22 to 70 %, while resistant staphylococci were absent in hard cheese and brine. The growth of lactic acid bacteria was not influenced by trimethoprim + sulphametoxazol (n=29, vancomycin (n=29, trimethoprim (n=28, amikacin (n=10 and tobramycin (n=10. The results show that significant part of apathogenic microbiota in different dairy products is phenotypically resistant to antimicrobial agents.

  11. Interactions of the cell-wall glycopolymers of lactic acid bacteria with their bacteriophages

    Marie-Pierre eChapot-Chartier

    2014-05-01

    Full Text Available Lactic acid bacteria (LAB are Gram positive bacteria widely used in the production of fermented food in particular cheese and yoghurts. Bacteriophage infections during fermentation processes have been for many years a major industrial concern and have stimulated numerous research efforts. Better understanding of the molecular mechanisms of bacteriophage interactions with their host bacteria is required for the development of efficient strategies to fight against infections. The bacterial cell wall plays key roles in these interactions. First, bacteriophages must adsorb at the bacterial surface through specific interactions with receptors that are cell wall components. At next step, phages must overcome the barrier constituted by cell wall peptidoglycan to inject DNA inside bacterial cell. Also at the end of the infection cycle, phages synthesize endolysins able to hydrolyze peptidoglycan and lyse bacterial cells to release phage progeny. In the last decade, concomitant development of genomics and structural analysis of cell wall components allowed considerable advances in the knowledge of their structure and function in several model LAB. Here, we describe the present knowledge on the structure of the cell wall glycopolymers of the best characterized LAB emphasizing their structural variations and we present the available data regarding their role in bacteria-phage specific interactions at the different steps of the infection cycle.

  12. Impairment of cellulose- and cellobiose-degrading soil Bacteria by two acidic herbicides.

    Schellenberger, Stefanie; Drake, Harold L; Kolb, Steffen

    2012-02-01

    Herbicides have the potential to impair the metabolism of soil microorganisms. The current study addressed the toxic effect of bentazon and 4-chloro-2-methylphenoxyacetic acid on aerobic and anaerobic Bacteria that are involved in cellulose and cellobiose degradation in an agricultural soil. Aerobic saccharide degradation was reduced at concentrations of herbicides above environmental values. Microbial processes (e.g. fermentations, ferric iron reduction) that were linked to anaerobic cellulose and cellobiose degradation were reduced in the presence of both herbicides at concentrations above and at those that occur in crop field soil. 16S rRNA gene transcript numbers of total Bacteria, and selected bacterial taxa (Clostridia [Group I], Planctomycetaceae, and two uncultivated taxa of Bacteroidetes) decreased more in anoxic than in oxic cellulose-supplemented soil microcosms in the presence of both herbicides. Collectively, the results suggested that the metabolism of anaerobic cellulose-degrading Bacteria was impaired by typical in situ herbicide concentrations, whereas in situ concentrations did not impair metabolism of aerobic cellulose- and cellobiose-degrading soil Bacteria. PMID:22098368

  13. Incidence of Bacteriocins Produced by Food-Related Lactic Acid Bacteria Active towards Oral Pathogens

    Konstantinos Papadimitriou

    2013-02-01

    Full Text Available In the present study we investigated the incidence of bacteriocins produced by 236 lactic acid bacteria (LAB food isolates against pathogenic or opportunistic pathogenic oral bacteria. This set of LAB contained several strains (≥17% producing bacteriocins active against food-related bacteria. Interestingly only Streptococcus macedonicus ACA-DC 198 was able to inhibit the growth of Streptococcus oralis, Streptococcus sanguinis and Streptococcus gordonii, while Lactobacillus fermentum ACA-DC 179 and Lactobacillus plantarun ACA-DC 269 produced bacteriocins solely against Streptococcus oralis. Thus, the percentage of strains that were found to produce bacteriocins against oral bacteria was ~1.3%. The rarity of bacteriocins active against oral LAB pathogens produced by food-related LAB was unexpected given their close phylogenetic relationship. Nevertheless, when tested in inhibition assays, the potency of the bacteriocin(s of S. macedonicus ACA-DC 198 against the three oral streptococci was high. Fourier-transform infrared spectroscopy combined with principal component analysis revealed that exposure of the target cells to the antimicrobial compounds caused major alterations of key cellular constituents. Our findings indicate that bacteriocins produced by food-related LAB against oral LAB may be rare, but deserve further investigation since, when discovered, they can be effective antimicrobials.

  14. Promotion of Intestinal Epithelial Cell Turnover by Commensal Bacteria: Role of Short-Chain Fatty Acids.

    Jung-Ha Park

    Full Text Available The life span of intestinal epithelial cells (IECs is short (3-5 days, and its regulation is thought to be important for homeostasis of the intestinal epithelium. We have now investigated the role of commensal bacteria in regulation of IEC turnover in the small intestine. The proliferative activity of IECs in intestinal crypts as well as the migration of these cells along the crypt-villus axis were markedly attenuated both in germ-free mice and in specific pathogen-free (SPF mice treated with a mixture of antibiotics, with antibiotics selective for Gram-positive bacteria being most effective in this regard. Oral administration of chloroform-treated feces of SPF mice to germ-free mice resulted in a marked increase in IEC turnover, suggesting that spore-forming Gram-positive bacteria contribute to this effect. Oral administration of short-chain fatty acids (SCFAs as bacterial fermentation products also restored the turnover of IECs in antibiotic-treated SPF mice as well as promoted the development of intestinal organoids in vitro. Antibiotic treatment reduced the phosphorylation levels of ERK, ribosomal protein S6, and STAT3 in IECs of SPF mice. Our results thus suggest that Gram-positive commensal bacteria are a major determinant of IEC turnover, and that their stimulatory effect is mediated by SCFAs.

  15. Promotion of Intestinal Epithelial Cell Turnover by Commensal Bacteria: Role of Short-Chain Fatty Acids.

    Park, Jung-Ha; Kotani, Takenori; Konno, Tasuku; Setiawan, Jajar; Kitamura, Yasuaki; Imada, Shinya; Usui, Yutaro; Hatano, Naoya; Shinohara, Masakazu; Saito, Yasuyuki; Murata, Yoji; Matozaki, Takashi

    2016-01-01

    The life span of intestinal epithelial cells (IECs) is short (3-5 days), and its regulation is thought to be important for homeostasis of the intestinal epithelium. We have now investigated the role of commensal bacteria in regulation of IEC turnover in the small intestine. The proliferative activity of IECs in intestinal crypts as well as the migration of these cells along the crypt-villus axis were markedly attenuated both in germ-free mice and in specific pathogen-free (SPF) mice treated with a mixture of antibiotics, with antibiotics selective for Gram-positive bacteria being most effective in this regard. Oral administration of chloroform-treated feces of SPF mice to germ-free mice resulted in a marked increase in IEC turnover, suggesting that spore-forming Gram-positive bacteria contribute to this effect. Oral administration of short-chain fatty acids (SCFAs) as bacterial fermentation products also restored the turnover of IECs in antibiotic-treated SPF mice as well as promoted the development of intestinal organoids in vitro. Antibiotic treatment reduced the phosphorylation levels of ERK, ribosomal protein S6, and STAT3 in IECs of SPF mice. Our results thus suggest that Gram-positive commensal bacteria are a major determinant of IEC turnover, and that their stimulatory effect is mediated by SCFAs. PMID:27232601

  16. The Occurrence of Beer Spoilage Lactic Acid Bacteria in Craft Beer Production.

    Garofalo, Cristiana; Osimani, Andrea; Milanović, Vesna; Taccari, Manuela; Aquilanti, Lucia; Clementi, Francesca

    2015-12-01

    Beer is one of the world's most ancient and widely consumed fermented alcoholic beverages produced with water, malted cereal grains (generally barley and wheat), hops, and yeast. Beer is considered an unfavorable substrate of growth for many microorganisms, however, there are a limited number of bacteria and yeasts, which are capable of growth and may spoil beer especially if it is not pasteurized or sterile-filtered as craft beer. The aim of this research study was to track beer spoilage lactic acid bacteria (LAB) inside a brewery and during the craft beer production process. To that end, indoor air and work surface samples, collected in the brewery under study, together with commercial active dry yeasts, exhausted yeasts, yeast pellet (obtained after mature beer centrifugation), and spoiled beers were analyzed through culture-dependent methods and PCR-DGGE in order to identify the contaminant LAB species and the source of contamination. Lactobacillus brevis was detected in a spoiled beer and in a commercial active dry yeast. Other LAB species and bacteria ascribed to Staphylococcus sp., Enterobaceriaceae, and Acetobacter sp. were found in the brewery. In conclusion, the PCR-DGGE technique coupled with the culture-dependent method was found to be a useful tool for identifying the beer spoilage bacteria and the source of contamination. The analyses carried out on raw materials, by-products, final products, and the brewery were useful for implementing a sanitization plan to be adopted in the production plant. PMID:26489032

  17. Current status and emerging role of glutathione in food grade lactic acid bacteria

    Pophaly Sarang

    2012-08-01

    Full Text Available Abstract Lactic acid bacteria (LAB have taken centre stage in perspectives of modern fermented food industry and probiotic based therapeutics. These bacteria encounter various stress conditions during industrial processing or in the gastrointestinal environment. Such conditions are overcome by complex molecular assemblies capable of synthesizing and/or metabolizing molecules that play a specific role in stress adaptation. Thiols are important class of molecules which contribute towards stress management in cell. Glutathione, a low molecular weight thiol antioxidant distributed widely in eukaryotes and Gram negative organisms, is present sporadically in Gram positive bacteria. However, new insights on its occurrence and role in the latter group are coming to light. Some LAB and closely related Gram positive organisms are proposed to possess glutathione synthesis and/or utilization machinery. Also, supplementation of glutathione in food grade LAB is gaining attention for its role in stress protection and as a nutrient and sulfur source. Owing to the immense benefits of glutathione, its release by probiotic bacteria could also find important applications in health improvement. This review presents our current understanding about the status of glutathione and its role as an exogenously added molecule in food grade LAB and closely related organisms.

  18. Phylogenetic analysis of antimicrobial lactic acid bacteria from farmed seabass Dicentrarchus labrax.

    Bourouni, Ouissal Chahad; El Bour, Monia; Calo-Mata, Pilar; Mraouna, Radhia; Abedellatif, Boudabous; Barros-Velàzquez, Jorge

    2012-04-01

    The use of lactic acid bacteria (LAB) in the prevention or reduction of fish diseases is receiving increasing attention. In the present study, 47 LAB strains were isolated from farmed seabass ( Dicentrarchus labrax ) and were phenotypically and phylogenetically analysed by 16S rDNA and randomly amplified polymorphic DNA - polymerase chain reaction (RAPD-PCR). Their antimicrobial effect was tested in vitro against a wide variety of pathogenic and spoilage bacteria. Most of the strains isolated were enterococci belonging to the following species: Enterococcus faecium (59%), Enterococcus faecalis (21%), Enterococcus sanguinicola (4 strains), Enterococcus mundtii (1 strain), Enterococcus pseudoavium (1 strain), and Lactococcus lactis (1 strain). An Aerococcus viridans strain was also isolated. The survey of their antimicrobial susceptibility showed that all isolates were sensitive to vancomycin and exhibited resistance to between 4 and 10 other antibiotics relevant for therapy in human and animal medicine. Different patterns of resistance were noted for skin and intestines isolates. More than 69% (32 strains) of the isolates inhibited the growth of the majority of pathogenic and spoilage bacteria tested, including Listeria monocytogenes, Staphylococcus aureus, Aeromonas hydrophila, Aeromonas salmonicida, Vibrio anguillarum, and Carnobacterium sp. To our knowledge, this is the first report of bioactive enterococcal species isolated from seabass that could potentially inhibit the undesirable bacteria found in food systems. PMID:22439634

  19. Modelling the effect of lactic acid bacteria from starter- and aroma culture on growth of Listeria monocytogenes in cottage cheese

    Østergaard, Nina Bjerre; Eklöw, Annelie; Dalgaard, Paw

    2014-01-01

    Four mathematical models were developed and validated for simultaneous growth of mesophilic lactic acid bacteria from added cultures and Listeria monocytogenes, during chilled storage of cottage cheese with freshor cultured cream dressing. The mathematical models include the effect of temperature...... cheese to improvemodel performance. The inhibiting effect of mesophilic lactic acid bacteria from added cultures on growth of L. monocytogenes was efficiently modelled using the Jameson approach. The new models appropriately predicted the maximum population density of L. monocytogenes in cottage cheese....... The developed models were successfully validated by using 25 growth rates for L. monocytogenes, 17 growth rates for lactic acid bacteria and a total of 26 growth curves for simultaneous growth of L. monocytogenes and lactic acid bacteria in cottage cheese. These data were used in combination with bias...

  20. The aflatoxin B1 isolating potential of two lactic acid bacteria

    Adel Hamidi; Reza Mirnejad; Emad Yahaghi; Vahid Behnod; Ali Mirhosseini; Sajad Amani; Sara Sattari; Ebrahim Khodaverdi Darian

    2013-01-01

    Objective:To determine lactic acid bacteria’s capability to enhance the process of binding and isolating aflatoxin B1 and to utilize such lactic acid bacteria as a food supplement or probiotic products for preventing absorption of aflatoxin B1 in human and animal bodies. Methods: In the present research, the bacteria were isolated from five different sources. For surveying the capability of the bacteria in isolating aflatoxin B1, ELISA method was implemented, and for identifying the resultant strains through 16S rRNA sequencing method, universal primers were applied. Results: Among the strains which were isolated, two strains of Lactobacillus pentosus and Lactobacillus beveris exhibited the capability of absorbing and isolating aflatoxin B1 by respectively absorbing and discharging 17.4%and 34.7%of the aforementioned toxin existing in the experiment solution. Conclusions:Strains of Lactobacillus pentosus and Lactobacillus beveris were isolated from human feces and local milk samples, respectively. And both strains has the ability to isolate or bind with aflatoxin B1.

  1. Coexistence of Lactic Acid Bacteria and Potential Spoilage Microbiota in a Dairy Processing Environment.

    Stellato, Giuseppina; De Filippis, Francesca; La Storia, Antonietta; Ercolini, Danilo

    2015-11-01

    Microbial contamination in food processing plants can play a fundamental role in food quality and safety. In this study, the microbiota in a dairy plant was studied by both 16S rRNA- and 26S rRNA-based culture-independent high-throughput amplicon sequencing. Environmental samples from surfaces and tools were studied along with the different types of cheese produced in the same plant. The microbiota of environmental swabs was very complex, including more than 200 operational taxonomic units with extremely variable relative abundances (0.01 to 99%) depending on the species and sample. A core microbiota shared by 70% of the samples indicated a coexistence of lactic acid bacteria with a remarkable level of Streptococcus thermophilus and possible spoilage-associated bacteria, including Pseudomonas, Acinetobacter, and Psychrobacter, with a relative abundance above 50%. The most abundant yeasts were Kluyveromyces marxianus, Yamadazyma triangularis, Trichosporon faecale, and Debaryomyces hansenii. Beta-diversity analyses showed a clear separation of environmental and cheese samples based on both yeast and bacterial community structure. In addition, predicted metagenomes also indicated differential distribution of metabolic pathways between the two categories of samples. Cooccurrence and coexclusion pattern analyses indicated that the occurrence of potential spoilers was excluded by lactic acid bacteria. In addition, their persistence in the environment can be helpful to counter the development of potential spoilers that may contaminate the cheeses, with possible negative effects on their microbiological quality. PMID:26341209

  2. Screening of species-specific lactic acid bacteria for veal calves multi-strain probiotic adjuncts.

    Ripamonti, Barbara; Agazzi, Alessandro; Bersani, Carla; De Dea, Paola; Pecorini, Chiara; Pirani, Silvia; Rebucci, Raffaella; Savoini, Giovanni; Stella, Simone; Stenico, Alberta; Tirloni, Erica; Domeneghini, Cinzia

    2011-06-01

    The selection of promising specific species of lactic acid bacteria with potential probiotic characteristics is of particular interest in producing multi species-specific probiotic adjuncts in veal calves rearing. The aim of the present work was to select and evaluate in vitro the functional activity of lactic acid bacteria, Bifidobacterium longum and Bacillus coagulans strains isolated from veal calves in order to assess their potential use as multi species-specific probiotics for veal calves. For this purpose, bacterial strains isolated from faeces collected from 40 healthy 50-day-calves, were identified by RiboPrinter and 16s rRNA gene sequence. The most frequent strains belonged to the species B. longum, Streptococcus bovis, Lactobacillus animalis and Streptococcus macedonicus. Among these, 7 strains were chosen for testing their probiotic characteristics in vitro. Three strains, namely L. animalis SB310, Lactobacillus paracasei subsp. paracasei SB137 and B. coagulans SB117 showed varying individual but promising capabilities to survive in the gastrointestinal tract, to adhere, to produce antimicrobial compounds. These three selected species-specific bacteria demonstrated in vitro, both singularly and mixed, the functional properties needed for their use as potential probiotics in veal calves. PMID:21619939

  3. Aflatoxin B1 binding by dairy strains of lactic acid bacteria and bifidobacteria.

    Peltonen, K; el-Nezami, H; Haskard, C; Ahokas, J; Salminen, S

    2001-10-01

    Various food commodities including dairy products may be contaminated with aflatoxins, which, even in small quantities, have detrimental effects on human and animal health. Several microorganisms have been reported to bind or degrade aflatoxins in foods and feeds. This study assessed the binding of aflatoxin B1 (AFB1) from contaminated solution by 20 strains of lactic acid bacteria and bifidobacteria. The selected strains are used in the food industry and comprised 12 Lactobacillus, five Bifidobacterium, and three Lactococcus strains. Bacteria and AFB1 were incubated (24 h, +37 degrees C) and the amount of unbound AFB1 was quantitated by HPLC. Between 5.6 and 59.7% AFB1 was bound from solution by these strains. Two Lactobacillus amylovorus strains and one Lactobacillus rhamnosus strain removed more than 50% AFB1 and were selected for further study. Bacterial binding of AFB1 by these strains was rapid, and more than 50% AFB1 was bound throughout a 72-h incubation period. Binding was reversible, and AFB1 was released by repeated aqueous washes. These findings further support the ability of specific strains of lactic acid bacteria to bind selected dietary contaminants. PMID:11699445

  4. Influence of Perfluorooctanoic Acid on the Transport and Deposition Behaviors of Bacteria in Quartz Sand.

    Wu, Dan; Tong, Meiping; Kim, Hyunjung

    2016-03-01

    The significance of perfluorooctanoic acid (PFOA) on the transport and deposition behaviors of bacteria (Gram-negative Escherichia coli and Gram-positive Bacillus subtilis) in quartz sand is examined in both NaCl and CaCl2 solutions at pH 5.6 by comparing both breakthrough curves and retained profiles with PFOA in solutions versus those without PFOA. All test conditions are found to be highly unfavorable for cell deposition regardless of the presence of PFOA; however, 7%-46% cell deposition is observed depending on the conditions. The cell deposition may be attributed to micro- or nanoscale roughness and/or to chemical heterogeneity of the sand surface. The results show that, under all examined conditions, PFOA in suspensions increases cell transport and decreases cell deposition in porous media regardless of cell type, presence or absence of extracellular polymeric substances, ionic strength, and ion valence. We find that the additional repulsion between bacteria and quartz sand caused by both acid-base interaction and steric repulsion as well as the competition for deposition sites on quartz sand surfaces by PFOA are responsible for the enhanced transport and decreased deposition of bacteria with PFOA in solutions. PMID:26866280

  5. ISOLATION OF LACTIC ACID BACTERIA UNDER LOW TEMPERATURE FOR THE PREPARATION OF YOGURT

    Javid Ahmad Bhat

    2014-02-01

    Full Text Available An investigation of isolation of Lactic acid bacteria was carried out under low temperature for the preparation of Yogurt by using various food supplements like carrot, ground-nut and tomato juices. Methods: Various samples of Cow milk, Skimmed milk were processed along with nutrients like Carrot, ground nut and tomato juices with Tryptone glucose yeast extract agar (TGYA at different temperatures like 50C, 150C and 220C for the isolation of Lactic acid bacteria for the preparation of yogurt. The characteristic isolates were identified by using various biochemical tests and direct microscopy. Results: Lactic acid bacteria (LAB dominated the microbial population of Yogurt, and were identified according to their morphological and physiological characteristics. Among these lactobacilli were frequently occurring organisms. The most abundant species were Lactobacillus delbrueckii subspecies Bulgaricus and Streptococcus thermophilus. The Lactic Streptococci was subjected to bio-chemical tests to identify the species. Based on the biochemical reactions the species was identified as Lactococcus Lactis, sub species di-acetylactis. Isolated culture of lactic Streptococci was found to grow at low temperature. When this was used as an inoculum to prepare yogurt at 50C, 150C and 220C curdling took place in 3days time. In order to reduce the setting time, nutrients in the form of carrot, ground-nut and tomato juices were added. The yogurt was found to set at 50C in 30hrs which is considered useful. Acidity of yogurt was found to be 0.53%- 0.55%. The yogurt was found to contain di-acetyl and quality of yogurt was good.

  6. BIOCHEMICAL CHARACTERISTICS OF LACTIC ACID PRODUCING BACTERIA AND PREPARATION OF CAMEL MILK CHEESE BY USING STARTER CULTURE

    T. Ahmed and R. Kanwal

    2004-01-01

    Lactic acid bacteria (LAB) were isolated from camel milk by culturing the milk on specific media and pure culture was obtained by sub-culturing. Purification of culture was confirmed by Gram’s staining and identified by different biochemical tests. Camel milk contained lactic acid producing bacteria like Streptococci such as S. cremoris and S. lactis and Lactobacilli such as L. acidophilus. L. acidophilus grew more rapidly in camel milk than others as its growth was supported by camel milk...

  7. Stable carbon isotope analysis of nucleic acids to trace sources of dissolved substrates used by estuarine bacteria.

    Coffin, R B; Velinsky, D J; R. Devereux; Price, W A; Cifuentes, L A

    1990-01-01

    The natural abundance of stable carbon isotopes measured in bacterial nucleic acids extracted from estuarine bacterial concentrates was used to trace sources of organic matter for bacteria in aquatic environments. The stable carbon isotope ratios of Pseudomonas aeruginosa and nucleic acids extracted from cultures resembled those of the carbon source on which bacteria were grown. The carbon isotope discrimination between the substrate and total cell carbon from bacterial cultures averaged 2.3%...

  8. Metabolite changes during natural and lactic acid bacteria fermentations in pastes of soybeans and soybean–maize blends

    Ng'ong'ola-Manani, Tinna A; Østlie, Hilde Marit; Mwangwela, Agnes M.; Wicklund, Trude

    2014-01-01

    The effect of natural and lactic acid bacteria (LAB) fermentation processes on metabolite changes in pastes of soybeans and soybean–maize blends was studied. Pastes composed of 100% soybeans, 90% soybeans and 10% maize, and 75% soybeans and 25% maize were naturally fermented (NFP), and were fermented by lactic acid bacteria (LFP). LAB fermentation processes were facilitated through back-slopping using a traditional fermented gruel, thobwa as an inoculum. Naturally fermented ...

  9. Effect of Lactic Acid Bacteria on Lipid Metabolism and Fat Synthesis in Mice Fed a High-fat Diet

    YONEJIMA, Yasunori; Ushida, Kazunari; Mori, Yoshiro

    2013-01-01

    Visceral fat accumulation is a major risk factor for the development of obesity-related diseases, including diabetes, hyperlipidemia, hypertension, and arteriosclerosis. Stimulation of lipolytic activity in adipose tissue or inhibition of fat synthesis is one way to prevent these serious diseases. Lactic acid bacteria have an anti-obesity effect, but the mechanisms are unclear. Therefore, we evaluated the effect of the administration of lactic acid bacteria (Lactobacillus gasseri NT) on lipid...

  10. Fermentation by amylolytic lactic acid bacteria and consequences for starch digestibility of plantain, breadfruit, and sweet potato flours

    Haydersah, J.; Chevallier, I.; Rochette, Isabelle; Mouquet Rivier, Claire; Picq, Christian; Marianne Pépin, T.; Icard-Vernière, Christèle; Guyot, Jean-Pierre

    2012-01-01

    The potential of tropical starchy plants such as plantain (Musa paradisiaca), breadfruit (Artocarpus communis), and sweet potato (Ipomoea batatas) for the development of new fermented foods was investigated by exploiting the capacity of some lactic acid bacteria to hydrolyze starch. The amylolytic lactic acid bacteria (ALAB) Lactobacillus plantarum A6 and Lactobacillus fermentum Ogi E1 were able to change the consistency of thick sticky gelatinized slurries of these starchy fruits and tubers ...

  11. THE EFFECTS OF INOCULANT LACTIC ACID BACTERIA ON THE FERMENTATION AND AEROBIC STABILITY OF SUNFLOWER SILAGE

    Fisun Koc

    2009-12-01

    Full Text Available This study was carried out to determine the effects of actic acid bacterial inoculant on the fermentation and aerobic stability of sunflower silages. Sunflower was harvested at the milk stage. Inoculant-1174 (Pioneer®,USA was used as homofermentative lactic acid bacterial inoculant. Inoculant was applied 6.00 log10 cfu/g silage levels. Silages with no additive served as controls. After treatment, the chopped sunflower was ensiled in the PVC type laboratory silos. Three silos for each group were sampled for chemical and microbiological analysis on days 2, 4, 7, 14, 21, 28 and 56 after ensiling. At the end of the ensiling period, all silages were subjected to an aerobic stability test for 14 days. Neither inoculant improved the fermentation parameters of sunflower silages. At the end of the ensiling period, inoculant increased lactic acid bacteria (LAB and decreased yeast and mould numbers of silages. Inoculant treatment did not affect aerobic stability of silages.

  12. Isolation of lactic acid bacteria from Malaysian foods and assessment of the isolates for industrial potential.

    Mohd Adnan, Ahmad Faris; Tan, Irene K P

    2007-05-01

    Two traditional fermented food 'tapai' (fermented tapioca) and 'tempoyak' (fermented durian flesh), chilli puree and fresh goat's milk were used as sources for the isolation of lactic acid bacteria (LAB). A total of 126 isolates were obtained and by sequential screening for catalase activity and Gram-staining, 55 were determined to be LAB out of which 16 were established to be homofermentative by the gel plug test. Seven isolates were identified by use of the API 50CHL kit and two lactobacilli strains and one lactococci strain were selected to study their growth and lactic acid production profiles in a time course experiment. The lactobacilli strains, both isolated from 'tapai', produced higher amounts of cells and lactic acid from glucose as compared to the lactococci strain isolated from fresh goat's milk. PMID:16872826

  13. Screening of potential probiotic lactic acid bacteria based on gastrointestinal properties and perfluorooctanoate toxicity.

    Xing, Jiali; Wang, Fan; Xu, Qi; Yin, Boxing; Fang, Dongsheng; Zhao, Jianxin; Zhang, Hao; Chen, Yong Q; Wang, Gang; Chen, Wei

    2016-08-01

    The consumption of lactic acid bacteria capable of binding or degrading food-borne carcinogens may reduce human exposure to these deleterious compounds. In this study, 25 Lactobacillus strains isolated from human, plant, or dairy environments were investigated for their potential probiotic capacity against perfluorooctanoate (PFOA) toxicity. The PFOA binding, tolerance ability, and acid and bile salt tolerance were investigated and assessed by principal component analysis. Additionally, the effect of different pH levels and binding times was assessed. These strains exhibited different degrees of PFOA binding; the strain with the highest PFOA binding capability was Lactobacillus plantarum CCFM738, which bound to 49.40 ± 1.5 % of available PFOA. This strain also exhibited relatively good cellular antioxidative properties, acid and bile salt tolerance, and adhesion to Caco-2 cells. This study suggests that L. plantarum CCFM738 could be used as a potential probiotic in food applications against PFOA toxicity. PMID:27094185

  14. Antisera production to detect indoleacetic acid in cultures of plant-growth promoting bacteria

    Rabbit polyclonal antisera against indoleacetic acid (IAA) bound to nitrocellulose membrane were obtained, which exhibited a high titer and specificity. The dot immunobinding technique with colloidal gold was used to detect auxin production by several strains belonging to Gluconacetobacter, Herbaspirillum, Azospirillum, Pseudomonas, Burkholderia and Bacillus genera, using culture supernatants as antigens. Moreover, auxin production was quantified by the Salkowski's method to corroborate the previous results. It was found that that all the studied microorganisms produce IAA and the feasibility of using these antisera to detect the metabolite was confirmed. Taking into account the potentialities of plant growth promoting bacteria as biofertilizers, the use of these antisera for a rapid and easy detection of IAA in bacteria associated with important crops is thus recommended.

  15. Effects of Lactic Acid Bacteria Fermentation on the Quality of Little Yellow Croaker

    Yuan Wu

    2013-11-01

    Full Text Available This research was to study the effects of lactic acid bacteria fermentation on the quality of little yellow croaker. The effects of the LAB starter composed of Lactobacillus plantarum and Lactobacillus acidophilus on the quality of little yellow croaker were studied through a 72 h fermentation process in this study. During 72 h fermentation at 30°C, little yellow croaker inoculated with the LAB starter not only resulted in a rapid pH decrease and suppression of spoilage bacteria, but also receded chemical changes such as total volatile base nitrogen and biogenic amines, its texture profile and whiteness also satisfying. Besides, Scanning Electron Micrograph (SEM images indicated some microstructure changes in LAB fermentation. The results demonstrated that the LAB starter could be developed as bio-preservatives to improve the quality of little yellow croaker in storage.

  16. Biotechnological and in situ food production of polyols by lactic acid bacteria.

    Ortiz, Maria Eugenia; Bleckwedel, Juliana; Raya, Raúl R; Mozzi, Fernanda

    2013-06-01

    Polyols such as mannitol, erythritol, sorbitol, and xylitol are naturally found in fruits and vegetables and are produced by certain bacteria, fungi, yeasts, and algae. These sugar alcohols are widely used in food and pharmaceutical industries and in medicine because of their interesting physicochemical properties. In the food industry, polyols are employed as natural sweeteners applicable in light and diabetic food products. In the last decade, biotechnological production of polyols by lactic acid bacteria (LAB) has been investigated as an alternative to their current industrial production. While heterofermentative LAB may naturally produce mannitol and erythritol under certain culture conditions, sorbitol and xylitol have been only synthesized through metabolic engineering processes. This review deals with the spontaneous formation of mannitol and erythritol in fermented foods and their biotechnological production by heterofermentative LAB and briefly presented the metabolic engineering processes applied for polyol formation. PMID:23604535

  17. Characteristics of lactic acid bacteria isolates and their effect on silage fermentation of fruit residues.

    Yang, Jinsong; Tan, Haisheng; Cai, Yimin

    2016-07-01

    The natural lactic acid bacteria (LAB) population, chemical composition, and silage fermentation of fruit residues were studied. Eighty-two strains of LAB were isolated from fruit residues such as banana leaf and stem, pineapple peel, and papaya peel. All strains were gram-positive and catalase-negative bacteria, and they were divided into 7 groups (A-G) according to morphological and biochemical characters. Strains in groups A to F were rods, and group G was cocci. Group F produced gas from glucose; other groups did not. Groups A to C and F formed dl-lactic acid, whereas groups D, E, and G formed l-lactic acid. Based on the 16S rRNA gene sequence and DNA-DNA hybridization analysis, groups A to G strains were identified as Lactobacillus plantarum (54.9% of the total isolates), Lactobacillus paraplantarum (3.6%), Lactobacillus nagelii (8.5%), Lactobacillus perolens (4.9%), Lactobacillus casei (11.0%), Lactobacillus fermentum (9.8%), and Enterococcus gallinarum (7.3%), respectively. Lactobacillus plantarum and Lactobacillus casei are the most frequently isolated from fruit residues as a dominant species, and they could grow at a lower pH conditions and produce more lactic acid than other isolates. Pineapple and papaya peels contained higher crude protein (11.5-13.8%) and water-soluble carbohydrate (16.8-22.4%), but lower acid detergent fiber contents (21.2 to 26.4%) than banana stems and leaves (8.2% crude protein, 42.8% acid detergent fiber, and 5.1% water-soluble carbohydrate). Compared with banana stem and leaf silages, the pineapple and papaya peel silages were well preserved with a lower pH and higher lactate content. The study suggests that the fruit residues contain excellent LAB species and abundant feed nutrients, and that they can be preserved as silage to be potential food resources for livestock. PMID:27108171

  18. Characterization of N/sub 2/-fixing bacteria and their role in plant growth under humic acid treatment

    Diazo trophic bacteria isolated from rice belonged to the six genera i.e. Pseudomonas, Azospirillum, Azotobacter, Xanthobacter, Flavobacterium and Zoogloea. During reinoculation studies it was observed that the rice roots grow well under humic acid treatment. The maximum root length 49.5 cm, was recorded at 10 ppm in plants inoculated with Azospirillum strain K-1. The total plant dry weight increase was also observed with the same organism at the similar humic acid concentration. In wheat the bacterial inoculation or humic acid treatment separately increased the dry weight of plant, however the humic acid treatment followed by inoculation of bacteria always cause decrease in total dry weight of plants. (author)

  19. Antigenotoxic activity of lactic acid bacteria, prebiotics, and products of their fermentation against selected mutagens.

    Nowak, Adriana; Śliżewska, Katarzyna; Otlewska, Anna

    2015-12-01

    Dietary components such as lactic acid bacteria (LAB) and prebiotics can modulate the intestinal microbiota and are thought to be involved in the reduction of colorectal cancer risk. The presented study measured, using the comet assay, the antigenotoxic activity of both probiotic and non-probiotic LAB, as well as some prebiotics and the end-products of their fermentation, against fecal water (FW). The production of short chain fatty acids by the bacteria was quantified using HPLC. Seven out of the ten tested viable strains significantly decreased DNA damage induced by FW. The most effective of them were Lactobacillus mucosae 0988 and Bifidobacterium animalis ssp. lactis Bb-12, leading to a 76% and 80% decrease in genotoxicity, respectively. The end-products of fermentation of seven prebiotics by Lactobacillus casei DN 114-001 exhibited the strongest antigenotoxic activity against FW, with fermented inulin reducing genotoxicity by 75%. Among the tested bacteria, this strain produced the highest amounts of butyrate in the process of prebiotic fermentation, and especially from resistant dextrin (4.09 μM/mL). Fermented resistant dextrin improved DNA repair by 78% in cells pre-treated with 6.8 μM methylnitronitrosoguanidine (MNNG). Fermented inulin induced stronger DNA repair in cells pre-treated with mutagens (FW, 25 μM hydrogen peroxide, or MNNG) than non-fermented inulin, and the efficiency of DNA repair after 120 min of incubation decreased by 71%, 50% and 70%, respectively. The different degrees of genotoxicity inhibition observed for the various combinations of bacteria and prebiotics suggest that this effect may be attributable to carbohydrate type, SCFA yield, and the ratio of the end-products of prebiotic fermentation. PMID:26404012

  20. Efficacy of Locally Isolated Lactic Acid Bacteria Against Antibiotic-Resistant Uropathogens

    Manzoor, Asma; Ul-Haq, Ikram; Baig, Shahjhan; Qazi, Javed Iqbal; Seratlic, Sanja

    2016-01-01

    Background: Antibiotic resistance represents a serious global health threat to public health, so infections such as pneumonia and urinary tract infection (UTI) are becoming harder to treat. Therefore, it is necessary to develop an action plan to restrain the problem of antibiotic resistance. One approach in UTI control could be the use of lactobacilli because these indigenous inhabitants in human intestine have been found to play an important role in protecting the host from various infections. Objectives: We sought to check the efficacy of locally isolated Lactobacillus species to eradicate antibiotic-resistant pathogenic bacteria causing UTI. Materials and Methods: Lactic acid bacteria isolated from spoiled fruits and vegetables and grown in MRS medium were screened against multi-drug-resistant Candida albicans, Klebsiella pneumoniae, Pseudomonas aeruginosa, Escherichia coli, and Enterococcus fecalis. Results: Fifty-four lactic acid bacteria were isolated from spoiled fruits and vegetables, of which 11 Gram-positive and catalase-negative Lactobacillus isolates were identified by carbohydrate assimilation profiles as Lactobacillus acidophilus, L. paracasei, L. delbrueckii, L. casei, L. helveticus, L. brevis, L. salivarius, L. fermentum, L. rhamnosus, L. animalis, and L. plantarum. The latter organism had the highest abundance of all the samples, so its isolates were also verified through 16S rRNA gene sequencing. The isolated Lactobacilli were screened against multi-drug-resistant uropathogens, viz. C. albicans, P. aeruginosa, K. pneumoniae, E. fecalis, and E. coli. The growth inhibition zone (GIZ) was over 10 mm against all the uropathogenic test organisms, where L. fermentum and L. plantarum strains demonstrated remarkable inhibitory activities against E. coli and E. faecalis, with a GIZ up to 28 mm. The susceptibility test to 16 antibiotics showed multidrug resistance (3 to 5 antibiotics) among all the tested uropathogens. Conclusions: The obtained results

  1. Application of antimicrobial-producing lactic acid bacteria to control pathogens in ready-to-use vegetables.

    Vescovo, M; Torriani, S; Orsi, C; Macchiarolo, F; Scolari, G

    1996-08-01

    Five psychrotrophic strains of lactic acid bacteria (Lactobacillus casei, Lact. plantarum and Pediococcus spp.) were isolated from 22 samples of commercial salads. These strains were shown to inhibit Aeromonas hydrophila, Listeria monocytogenes, Salmonella typhimurium and Staphylococcus aureus on MRS agar, in salads and in juice prepared from vegetable salads. Lactobacillus casei IMPCLC34 was most effective in reducing total mesophilic bacteria and the coliform group; Aer. hydrophila, Salm. typhimurium and Staph. aureus disappeared after 6 d of storage, while the counts for L. monocytogenes remained constant. The potential application of antimicrobial-producing lactic acid bacteria as biopreservatives of ready-to-use vegetables is suggested. PMID:8760320

  2. Characteristic of cow milk dadih using starter of probiotic of lactic acid bacteria

    Sri Usmiati

    2011-06-01

    Full Text Available Dadih is an original dairy product from West Sumatera processed traditionally. It is a spontaneous fermentation of buffalo milk at room temperature for 48 hours in a bamboo tube, has no standard of processing and quality. Dadih is potentially to be develop into probiotic products (functional food that can be enjoyed by the public widely. Development of cow's milk dadih is necessary since buffalo milk is available only in certain area. Product and characteristic information of cow milk dadih using probiotic of lactic acid bacteria starter has not been known. The research objective was to determine the characteristics of cow milk dadih that used starter of probiotic lactic acid bacteria during storage at room temperature (27oC and cold temperature (4oC. The study was designed using a factorial randomized block design pattern 12x3 at room temperature and 12X4 at cold temperatures, with the number of repeatation of 3 times. Treatment consisted of: (i starter formula (A using a single bacterium or a combination of Lactobacillus acidophilus, Lactobacillus casei and Bifidobacterium longum, and (ii storage time (B. Observed parameters included pH value, titrable acidity, the total plate count, and in-vitro probiotic testing (bacterial resistance to bile salts and low pH of cow milk dadih. The results showed that L. acidophilus early exponential phase was at the hour 3rd, L. casei at the hour 4th and B. longum on the 3rd of which is used as the optimum time of mixing two or more bacteria in the manufacture of cow milk dadih. The volume of starter used was 3% with time fermentation of 48 hours at room temperature (27-30oC. Cow milk dadih that was stored for 7 days at room temperature (27-30oC and for 21 days at cold temperatures (4-10oC was able to maintain viability of bacteria to bile salts and low pH at 1010-1012 cfu/ml with percentage resistance varied. The cow milk dadih using a combination starter of B. longum with other probiotics on the

  3. Caciotta della Garfagnana cheese: selection and evaluation of autochthonous mesophilic lactic acid bacteria as starter cultures

    Domenico Cerri

    2011-04-01

    Full Text Available The aim of this study was to isolate, identify and select, with respect to acidification and proteolytic activities, the autochthonous mesophilic lactic acid bacteria (LAB present in milk and Caciotta della Garfagnana, a cheese produced either with raw or thermised cow’s milk in small dairies and family plants of Garfagnana (Tuscany, to obtain LAB strains with attributes suitable to be employed as starter cultures in this type of cheese, particularly when thermised milk is used to control spoilage microflora. Samples of raw milk, curd and cheese were collected from three representative farmers of the production area and used to isolate autochthonous LAB. Phenotypic and genotypic (species-specific PCR assay identification of isolated LAB was done. Twenty-eight strains of LAB isolated from milk, curd and cheese were screened for acidifying and proteolytic activities. LAB strains with the better attributes were used as mesophilic starter cultures in technological trials: experimental cheeses manufactured with the addition of autochthonous LAB and control cheeses were compared for LAB and pH evolution. Experimental cheeses presented a significant increase in the mesophilic lactic acid microflora up to 14 days of ripening and significantly lower pH values up to seven days of ripening. The use of wild selected mesophilic lactic acid bacteria, together with thermisation of milk, for the Caciotta della Garfagnana looks very promising and could help to both standardise the production and improve quality and traditional characteristics of this type of cheese.

  4. Caciotta della Garfagnana cheese: selection and evaluation of autochthonous mesophilic lactic acid bacteria as starter cultures

    Barbara Turchi

    2011-05-01

    Full Text Available he aim of this study was to isolate, identify and select, with respect to acidification and proteolytic activities, the autochthonous mesophilic lactic acid bacteria (LAB present in milk and Caciotta della Garfagnana, a cheese produced either with raw or thermised cow’s milk in small dairies and family plants of Garfagnana (Tuscany, to obtain LAB strains with attributes suitable to be employed as starter cultures in this type of cheese, particularly when thermised milk is used to control spoilage microflora. Samples of raw milk, curd and cheese were collected from three representative farmers of the production area and used to isolate autochthonous LAB. Phenotypic and genotypic (species-specific PCR assay identification of isolated LAB was done. Twenty-eight strains of LAB isolated from milk, curd and cheese were screened for acidifying and proteolytic activities. LAB strains with the better attributes were used as mesophilic starter cultures in technological trials: experimental cheeses manufactured with the addition of autochthonous LAB and control cheeses were compared for LAB and pH evolution. Experimental cheeses presented a significant increase in the mesophilic lactic acid microflora up to 14 days of ripening and significantly lower pH values up to seven days of ripening. The use of wild selected mesophilic lactic acid bacteria, together with thermisation of milk, for the Caciotta della Garfagnana looks very promising and could help to both standardise the production and improve quality and traditional characteristics of this type of cheese.

  5. Antibiotic Resistance of Probiotic Strains of Lactic Acid Bacteria Isolated from Marketed Foods and Drugs

    CHANG LIU; ZHUO-YANG ZHANG; KE DONG; JIAN-PING YUAN; XIAO-KUI GUO

    2009-01-01

    Objective To identify the antimicrobial resistance of commercial lactic acid bacteria present in microbial foods and drug additives by analyzing their isolated strains used for fermentation and probioties. Methods Antimicrobial susceptibility of 41 screened isolates was tested with disc diffusion and E-test methods after species-level identification. Resistant strains were selected and examined for the presence of resistance genes by PCR. Results Distribution of resistance was found in different species. All isolates were susceptible to chloramphenicol, tetracycline, ampicillin, amoxicillin/clavulanic acid, cephalothin, and imipenem. In addition, isolates resistant to vancomycin, rifampicin, streptomycin, bacitracin, and erythromycin were detected, although the incidence of resistance to these antibiotics was relatively low. In contrast, most strains were resistant to ciprofloxacin, amikacin, trimethoprim/sulphamethoxazole, and gentamycin. The genes msrC, vanX, and dfrA were detected in strains of Enterococcus faecium, Lactobacillus plantarum, Streptococcus thermophilus, and Lactococcus lactis. Conclusion Antibiotic resistance is present in different species of probiotic strains, which poses a threat to food safety. Evaluation of the safety of lactic acid bacteria for human consumption should be guided by established criteria, guidelines and regulations.

  6. Screening of probiotic lactic acid bacteria from Thai fermented foods for human.

    Kantachote, D.

    2004-09-01

    Full Text Available Total of 327 strains of lactic acid bacteria were isolated from 179 samples of various Thai fermented foods. The strains were investigated for their probiotic properties based on stability in bile salt (0.15% and high acidity (pH 2, 3 and 4. Moreover, utilization of protein or fat or starch, growth in the absence of vitamin B12 and growth under both aerobic and anaerobic conditions with no significant difference were also considered. According to the above criteria, 67 strains were selected for antibiotics sensitivity test. The selected strains were susceptible to following antibiotics: ampicillin, cephalothin, cefoperazone, tetracycline andchloramphenicol; however the strains were resistant to vancomycin, kanamycin, streptomycin, norfloxacin and polymyxin B. Using agar spot method, only 5 strains were able to inhibit 13 strains of manifest by a bacteria indicator as clear zone greater than 10 mm. A further investigation using co-culture technique showed inhibition of the tested organisms was between 80 and 100 percent. The strains grew under media of MRS and SPY2 (no materials from animal over 36 hours with no significant difference. The strains were investigated for survival in condition of high acidity within 3 hours. It was found that at pH 4 almost 100% were maintained but at pH 2 and 3 the survival reduced approximately 1 log cycle. The strain LA71 which showed the highest survival was identified as Lactobacillus plantarum.

  7. Lactic acid bacteria activating innate immunity improve survival in bacterial infection model of silkworm.

    Nishida, Satoshi; Ono, Yasuo; Sekimizu, Kazuhisa

    2016-01-01

    Lactic acid bacteria (LAB) have been thought to be helpful for human heath in the gut as probiotics. It recently was noted that activity of LAB stimulating immune systems is important. Innate immune systems are conserved in mammals and insects. Silkworm has innate immunity in response to microbes. Microbe-associated molecular pattern (ex. peptidoglycan and β-glucan) induces a muscle contraction of silkworm larva. In this study, we established an efficient method to isolate lactic acid bacteria derived from natural products. We selected a highly active LAB to activate the innate immunity in silkworm by using the silkworm muscle contraction assay, as well. The assay revealed that Lactococcus lactis 11/19-B1 was highly active on the stimulation of the innate immunity in silkworm. L. lactis 11/19-B1 solely fermented milk with casamino acid and glucose. This strain would be a starter strain to make yogurt. Compared to commercially available yogurt LAB, L. lactis 11/19-B1 has higher activity on silkworm contraction. Silkworm normally ingested an artificial diet mixed with L. lactis 11/19-B1 or a yogurt fermented with L. lactis 11/19-B1. Interestingly, silkworms that ingested the LAB showed tolerance against the pathogenicity of Pseudomonas aeruginosa. These data suggest that Lactococcus lactis 11/19-B1 would be expected to be useful for making yogurt and probiotics to activate innate immunity. PMID:26971556

  8. Enrichment of conjugated linoleic acid (CLA) in hen eggs and broiler chickens meat by lactic acid bacteria.

    Herzallah, Saqer

    2013-01-01

    1. The aim of this work was to compare conjugated linoleic acid (CLA) concentrations in chickens supplemented with 4 American Tissue Culture Collection (ATCC) bacterial strains, Lactobacillus plantarum, Lactobacillus lactis, Lactobacillus casei and Lactobacillus fermentum, and 4 isolates of Lactobacillus reuteri from camel, cattle, sheep and goat rumen extracts. 2. Micro-organisms were grown anaerobically in MRS broth, and 10(6) CFU/ml of bacteria were administered orally to mixed-sex, 1-d-old broiler chickens weekly for 4 weeks and to 23-week-old layer hens weekly for 6 weeks. 3. The 4 strains were evaluated for their effects on synthesis of CLA in hen eggs and broiler meat cuts. 4. Administration of pure Lactobacillus and isolated L. reuteri strains from camel, cattle, goat and sheep led to significantly increased CLA concentrations of 0.2-1.2 mg/g of fat in eggs and 0.3-1.88 mg/g of fat in broiler chicken flesh homogenates of leg, thigh and breast. 5. These data demonstrate that lactic acid bacteria of animal origin (L. reuteri) significantly enhanced CLA synthesis in both eggs and broiler meat cuts. PMID:24397511

  9. Selection of oleuropein-degrading lactic acid bacteria strains isolated from fermenting Moroccan green olives

    Ghabbour, N.; Lamzira, Z.; Thonart, P.; Cidalia, P.; Markaouid, M.; Asehraoua, A.

    2011-07-01

    A total of 177 strains of lactic acid bacteria (LAB) were isolated from early-stage Moroccan Picholine green olive fermentation, including Lactobacillus plantarum (44.63%), Lactobacillus pentosus (25.99%), Lactobacillus brevis (9.61%) and Pediococcus pentosaceus (19.77%). All the isolates were screened for their tolerance to olive leaf extract and oleuropein. Most of the isolates (85.3%) were found able to degrade oleuropein, when evaluated by either oleuropein or 5-Bromo-4-chloro-3-indolyl {beta}-D-glucuronide (X-Gluc) as substrates. The biodegradation capacity of the selected strains of each species was confirmed by HPLC analysis. (Author).

  10. Growth of Bacteria on 3-Nitropropionic Acid as a Sole Source of Carbon, Nitrogen, and Energy▿

    Nishino, Shirley F.; Shin, Kwanghee A.; Payne, Rayford B.; Spain, Jim C.

    2010-01-01

    3-Nitropropionic acid (3NPA) is a widespread nitroaliphatic toxin found in a variety of legumes and fungi. Several enzymes have been reported that can transform the compound, but none led to the mineralization of 3NPA. We report here the isolation of bacteria that grow on 3NPA and its anion, propionate-3-nitronate (P3N), as the sole source of carbon, nitrogen, and energy. Experiments with resting cells, cell extracts, and purified enzymes indicate that the pathway involves conversion of 3NPA ...

  11. Selection of oleuropein-degrading lactic acid bacteria strains isolated from fermenting Moroccan green olives

    A total of 177 strains of lactic acid bacteria (LAB) were isolated from early-stage Moroccan Picholine green olive fermentation, including Lactobacillus plantarum (44.63%), Lactobacillus pentosus (25.99%), Lactobacillus brevis (9.61%) and Pediococcus pentosaceus (19.77%). All the isolates were screened for their tolerance to olive leaf extract and oleuropein. Most of the isolates (85.3%) were found able to degrade oleuropein, when evaluated by either oleuropein or 5-Bromo-4-chloro-3-indolyl β-D-glucuronide (X-Gluc) as substrates. The biodegradation capacity of the selected strains of each species was confirmed by HPLC analysis. (Author).

  12. Anti-listerial inhibitory lactic acid bacteria isolated from commercial cold smoked salmon

    Tome, Elisabetta; Teixeira, Paula; Gibbs, Paul A.

    2006-01-01

    The natural microflora of cold-smoked fish at the end of shelf-life are lactic acid bacteria (LAB). Some of these display a capacity to inhibit spoilage as well as several strains of pathogenic micro-organisms, e.g. Listeria monocytogenes which is isolated frequently from cold-smoked salmon (CSS). Eight batches of sliced vacuum-packed CSS from Norway, Scotland and Spain were collected at retail. Packs were stored at 5 1C and examined for chemical and microbiological characteristic...

  13. Identification of lactic acid bacteria isolated from Tarhana, a traditional Turkish fermented food

    Sengun, Ilkin Yucel; Nielsen, Dennis Sandris; Karapinar, Mehmet;

    2009-01-01

    Tarhana is a traditional fermented product produced from a mixture of spontaneously fermented yogurt and wheat flour in Turkey. The aims of the present study were to enumerate and identify for the first time by molecular biology-based methods predominant lactic acid bacteria (LAB) isolated during...... processing of Tarhana. Samples were collected from eight different regions of Turkey. In order to explore the relationship between raw material and the microbiology of Tarhana, yogurt and wheat flour were also analyzed. A total of 226 Gram-positive and catalase-negative isolates were obtained from MRS, M17...... and S. thermophilus was found to be the yogurt....

  14. Selection of oleuropein-degrading lactic acid bacteria strains isolated from fermenting Moroccan green olives

    Ghabbour, N.; Lamzira, Z.; Thonart, P.; Cidalia, P.; Markaoui, M.; Asehraou, A.

    2011-01-01

    A total of 177 strains of lactic acid bacteria (LAB) were isolated from early-stage Moroccan Picholine green olive fermentation, including Lactobacillus plantarum (44.63%), Lactobacillus pentosus (25.99%), Lactobacillus brevis (9.61%) and Pediococcus pentosaceus (19.77%). All the isolates were screened for their tolerance to olive leaf extract and oleuropein. Most of the isolates (85.3%) were found able to degrade ole...

  15. 2,4-Dichlorophenoxyacetic acid-degrading bacteria contain mosaics of catabolic genes.

    Fulthorpe, R R; McGowan, C; Maltseva, O V; Holben, W E; Tiedje, J M

    1995-01-01

    DNA from 32 2,4-dichlorophenoxyacetic acid (2,4-D)-degrading bacteria from diverse locations was probed with the first three genes of the well-known 2,4-D degradation pathway found in Alcaligenes eutrophus JMP134(pJP4). The majority of strains did not show high levels of homology to the first three genes of the 2,4-D degradation pathway, tfdA, -B, and -C. Most strains showed combinations of tfdA-, B-, and C-like elements that exhibited various degrees of homology to the gene probes. Strains h...

  16. Metabolic engineering of lactic acid bacteria for the production of industrially important compounds

    Maria Papagianni

    2012-10-01

    Full Text Available Lactic acid bacteria (LAB are receiving increased attention for use as cell factories for the production of metabolites with wide use by the food and pharmaceutical industries. The availability of efficient tools for genetic modification of LAB during the past decade permitted the application of metabolic engineering strategies at the levels of both the primary and the more complex secondary metabolism. The recent developments in the area with a focus on the production of industrially important metabolites will be discussed in this review.

  17. Diversity of lactic acid bacteria isolated from raw milk in Elsharkia province, Egypt

    Alnakip, Mohamed E. A.; Mohamed, Asmaa S.; Kamal, Rania M.; Elbadry, Seham

    2016-01-01

    A total of 50 raw cow’s milk samples were collected from different areas of Elsharkia province, Egypt for characterizing lactic acid bacteria (LAB) load. Using 16S rRNA gene sequencing, a total of 41 LAB isolates have been identified corresponding to Enterococcus sp. (51.22 %) as the most predominant LAB genus, followed in order by Aerococcus (26.82 %), Lactococcus (7.32 %), Lactobacillus (7.32 %), Leuconostic (4.88 %) and Pediococcus (2.44 %) genera. All isolates were identified to species l...

  18. Characterization, Identification and Application of Lactic Acid Bacteria Isolated from Forage Paddy Rice Silage

    Ni, Kuikui; Wang, Yanping; Li, Dongxia; Cai, Yimin; Pang, Huili

    2015-01-01

    There has been growing interest to develop forage rice as a new feed resource for livestock. This study was to characterize the natural population of lactic acid bacteria (LAB) and select potentially excellent strains for paddy rice silage preparation in China. One hundred and twenty-six strains were isolated and screened from paddy rice silage prepared using a small-scale fermentation system, and ninety-nine of these isolates were considered to be LAB based on their Gram-positive and catalas...

  19. Regulation of acid adaptation in Lactic acid bacteria%乳酸菌的适酸性调节

    乔磊; 崔艳华; 曲晓军

    2011-01-01

    The understanding of acid adaptation mechanisms of LAB will benefit screening the acid-tolerance bacteria, the optimization of procedures in the ferment progress and optimization of culture. This will greatly improve the quality of fermented foods. The acid adaptation mechanisms were discussed, including proton pump, the production of alkali, the changes of membrane, protection or repair of macro-molecules and the regulation of acid tolerance.%探讨了乳酸菌适酸机制有助于抗酸菌株的筛选、发酵过程中工序的优化以及培养基的优化等,进而大大提升发酵产品品质.对质子泵、产碱、细胞膜变化、大分子保护修复以及耐酸调节在内的适酸性调节机制进行了一一阐述.

  20. Application of lactic acid bacteria in removing heavy metals and aflatoxin B1 from contaminated water.

    Elsanhoty, Rafaat M; Al-Turki, I A; Ramadan, Mohamed Fawzy

    2016-01-01

    In this study selected lactic acid bacteria (LAB, Lactobacillus acidophilus, Lactobacillus rhamnosus, Lactobacillus plantrium and Streptococcus thermophiles) and probiotic bacteria (Bifidobacterium angulatum) were tested for their ability in removing heavy metals (HM) including cadmium (Cd), lead (Pb) and arsenic (As) as well as aflatoxin B1 (AFB1) from contaminated water. The biosorption parameters (pH, bacterial concentration, contact time and temperature) of removal using individual as well as mixed LAB and probiotic bacteria were studied. Removal of HM and AFB1 depended on the strain, wherein the process was strongly pH-dependent with high removal ability at a pH close to neutral. The increase in bacterial concentration enhanced the removal of Cd, Pb and As. Also, increasing of contact time and temperature increased the ability of LAB to remove HM. The effect of contact time on Cd removal was slightly different when freshly cultured cells were used. The removal of Cd, Pb and As decreased with the increase in the initial metal concentration. The most effective HM removers were Lactobacillus acidophilus and Bifidobacterium angulatum. The system was found to be adequate for concentrations of HM under investigation. At the end of the operation, the concentration of HM reached the level allowed by the World Health Organization regulations. PMID:27508367

  1. Inhibition Effect of Lactic Acid Bacteria against Food Born Pathogen, Listeria monocytogenes

    Rouha Kasra-Kermanshahi

    2015-09-01

    Full Text Available Disease caused by consuming microbial contaminated food has increased significantly in recent years due to changes in the livelihoods and eating habits of the human populations. Listeria monocytogenes, Escherichia coli O157:H7 and Salmonella enterica are three of the most important foodborne bacterial pathogens and can lead to foodborne diseases. Increased use of antibiotics, has led to development of bacterial resistance to antibiotics. Therefore, there is growing interest in the development of new types of effective and nontoxic antimicrobial compounds. Nowadays, the most extensive research and commercial practices are based on probiotic bacteria. Probiotics, specifically lactic acid bacteria are widely used in the food industry for fermentation but have gained attention from health professionals because of their potential beneficial effects. Now probiotic therapy is thought to be an effective way to improve the gut health and an alternative to antibiotic treatments. They contribute to food safety by their ability to inhibit the growth of several other bacteria. LAB can be used as protective cultures to compete with potential pathogens and other undesired organisms, thereby increasing the safety of the food product.

  2. Distribution of δ-aminolevulinic acid biosynthetic pathways among phototrophic and related bacteria

    Two biosynthetic pathways are known for the universal tetrapyrrole precursor, δ-aminolevulinic acid (ALA): condensation of glycine and succinyl-CoA to form ALA with the loss of C-1 of glycine as CO2, and conversion of the intact carbon skeleton of glutamate to ALA in a process requiring tRNAGlu, ATP, Mg2+, NADPH, and pyridoxal phosphate. The distribution of the two ALA biosynthetic pathways among various bacterial genera was determined, using cell-free extracts obtained from representative organisms. Evidence for the operation of the glutamate pathway was obtained by the measurement of RNase-sensitive label incorporation from glutamate into ALA using 3,4-[3H]glutamate and 1-[14C]glutamate as substrate. The glycine pathway was indicated by RNase-insensitive incorporation of level from 2-[14C]glycine into ALA. The distribution of the two pathways among the bacteria tested was in general agreement with their previously phylogenetic relationships and clearly indicates that the glutamate pathway is the more ancient process, whereas the glycine pathway probably evolved much later. The glutamate pathway is the more widely utilized one among bacteria, while the glycine pathway is apparently limited to the α subgroup of purple bacteria (including Rhodobacter, Rhodospirillum, and Rhizobium). E. coli was found ALA via the glutamate pathway. The ALA-requiring hemA mutant of E. coli was determined to lack the dehydrogenase activity that utilizes glutamyl-tRNA as a substrate

  3. Proteolytic Activity in Reduced-Fat Cheddar Cheese Made with Lactic Acid Bacteria and Camel Chymosin

    Børsting, Mette Winther

    need of an extended ripening period to reach a similar cheese structure as in cheeses produced with BC. The aim of this project was to compensate for the lower proteolytic activity in cheese produced with CC compared to BC. Selection of dairy lactic acid bacteria (LAB) for cheese production with high...... ability to influence proteolysis and structure during cheese ripening. In an attempt to improve the screening methods and contribute to the development of a new classification system of Latcococcus lactic strains, the peptide profile formed by selected strains after growth in milk was analyzed and...... culture mediated an increase in the total amount of amino acids as well as a shorter structure. A model system, used to study the retention of chymosin in a curd, showed that the retention of CC was less dependent on pH compared to BC, and the retention of CC was higher than BC in the pH interval 6...

  4. Selection of exopolysaccharide-producing lactic acid bacteria isolates from Inner Mongolian traditional yoghurt

    Zhang Chun-lei

    2014-11-01

    Full Text Available Lactic acid bacteria (LAB isolated from Inner Mongolian traditional yoghurt were evaluated for the production of exopolysaccharides (EPS by phenol-sulphuric acid method after ethanol precipitation and dialysis. Total polysaccharide was extracted from sucrose-containing MRS broth cultures of the selected LAB strains. Comparison of the EPS yields revealed that among tested LAB, strain 37 exhibited the highest production of 536.904 mg/L. The strain was identified as Leuconostoc citreum with carbohydrate assimilation profiling, 16S rRNA and pheS gene sequencing. The Ln. citreum 37 was found to be a novel EPS producing strain. It was found that there was no direct linear relation between the colony size and EPS yield, so the colony size could not to be used to screen EPS-producing strains.

  5. Potential of selected lactic acid bacteria to produce food compatible antifungal metabolites.

    De Muynck, Cassandra; Leroy, Annelies I J; De Maeseneire, Sofie; Arnaut, Filip; Soetaert, Wim; Vandamme, Erick J

    2004-01-01

    The aim of this study was to assess the potential of lactic acid bacteria to inhibit the outgrowth of some common food-spoiling fungi. Culture supernatants of 17 Lactic acid bacterial strains as well as of three commercial probiotic cultures were evaluated for antifungal activity using an agar-diffusion method. The method parameters were chosen in order to reveal compounds for potential use in food (bio)preservation. Thirteen strains showed antifungal activity of which five strains were very promising: Lactobacillus acidophilus LMG 9433, L. amylovorus DSM 20532, L. brevis LMG 6906, L. coryniformis subsp. coryniformis LMG 9196 and L. plantarum LMG 6907. Four of these five strains were further examined; it was found that the produced antifungal metabolites were pH-dependent. The exact chemical nature of these substances has not been revealed yet. PMID:15646380

  6. OBTAINING OF PROTEIC BIOMASS BY CULTIVATION OF LACTIC ACID BACTERIA ON GRAPE MARC DIFFUSION SOLUTION

    Marian BUTU

    2013-08-01

    Full Text Available In this article are presented the researches made in order to obtain protein biomass with the aid of lactic bacteria grown on an economically medium, achieved by using secondary products from the winery: marc and wine yeast. Therefore, there were cultivated two strains of Lactobacillus sp. on five different growth medium. The protein biosynthesis and evolution of lactic fermentation were monitored by determining the optical density (OD of the culture at a wavelength λ = 600 nm and by counting the colony forming units (CFU by serial dilutions and seeding on plates and by determination of lactic acid obtained. The results showed that the fermentation medium represented by diffusion solution of the marc, enriched with peptone is economically profitable compared to other culture media containing peptone, yeast extract, glucose, minerals, amino acids and vitamins presented in the literature.

  7. Draft Genome Sequences of Gluconobacter cerinus CECT 9110 and Gluconobacter japonicus CECT 8443, Acetic Acid Bacteria Isolated from Grape Must

    Sainz, Florencia

    2016-01-01

    We report here the draft genome sequences of Gluconobacter cerinus strain CECT9110 and Gluconobacter japonicus CECT8443, acetic acid bacteria isolated from grape must. Gluconobacter species are well known for their ability to oxidize sugar alcohols into the corresponding acids. Our objective was to select strains to oxidize effectively d-glucose. PMID:27365351

  8. Isolation of Lactic Acid Bacteria Showing Antioxidative and Probiotic Activities from Kimchi and Infant Feces.

    Ji, Keunho; Jang, Na Young; Kim, Young Tae

    2015-09-01

    The purpose of this study was to investigate lactic acid bacteria with antioxidative and probiotic activities isolated from Korean healthy infant feces and kimchi. Isolates A1, A2, S1, S2, and S3 were assigned to Lactobacillus sp. and isolates A3, A4, E1, E2, E3, and E4 were assigned to Leuconostoc sp. on the basis of their physiological properties and 16S ribosomal DNA sequence analysis. Most strains were confirmed as safe bioresources through nonhemolytic activities and non-production of harmful enzymes such as β-glucosidase, β- glucuronidase and tryptophanase. The 11 isolates showed different resistance to acid and bile acids. In addition, they exhibited antibacterial activity against foodborne bacteria, especially Bacillus cereus, Listeria monocytogenes, and Escherichia coli. Furthermore, all strains showed significantly high levels of hydrophobicity. The antioxidant effects of culture filtrates of the 11 strains included 2,2-diphenyl-1-picryl-hydrazyl (DPPH) radical scavenging capacity, 2.2'- azino-bis (2-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical cation scavenging activity, and superoxide dismutase activity. The results revealed that most of the culture filtrates have effective scavenging activity for DPPH and ABTS radicals. All strains appeared to have effective superoxide dismutase activity. In conclusion, the isolated strains A1, A3, S1, and S3 have significant probiotic activities applicable to the development of functional foods and health-related products. These strains might also contribute to preventing and controlling several diseases associated with oxidative stress, when used as probiotics. PMID:25951843

  9. Peptidoglycan Hydrolases of Local Lactic Acid Bacteria from Kazakh Traditional Food

    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.

  10. Aflatoxin M1 in raw milk and binding of aflatoxin by lactic acid bacteria

    Aflatoxin M1 in raw milk and binding of aflatoxin by lactic acid bacteria

    2010-12-01

    Full Text Available Aflatoxin M1 (AFM1 is potential human carcinogen. Its presence in milk and dairy products represents risk for human health. Therefore, this study was carried out in order to determine thedegree of microbiological contamination by mold, and the potential presence of aflatoxin M1 in 60 raw milk samples, randomly taken from individual producers from different regions of the continental Croatia. The most common genera isolated fungi were Geotrichum (78.3 %, Aspergillus (32.4 % and Penicillium (27.0 %. From total of 60 studied milk samples, 86.66 % were positive for the presence of aflatoxin M1, and 6.66 % of samples were above the prescribed limits. Lactic acid bacteria used in fermented dairy products as a starter culture may play a role in reduction of aflatoxin in foods and nutrients. In this paper the ability of lactic acid bacteria: Lactobacillus rhamnosus GG (ATCC 53103, Lactobacillus delbrueckii S1 and Lactobacillus plantarum A1 to bind aflatoxin M1 was investigated. Standard strain L. rhamnosus GG (ATCC 53103 and L. delbrueckii S1 can significantly (P50 % compared to L. plantarum A1, which binds AFM1 between 18.7 to 28.7 %.

  11. Effect of lactic acid bacteria isolated from fermented mustard on immunopotentiating activity

    Chen-Kai; Chang; Shu-Chen; Wang; Chih-Kwang; Chiu; Shih-Ying; Chen; Zong-Tsi; Chen; Pin-Der; Duh

    2015-01-01

    Objective: To investigate the effect of lactic acid bacteria isolated from fermented mustard on immunopotentiating activity Methods: One hundred and fifty nine strains of lactic acid bacteria isolated from traditional Taiwan fermented mustard were evaluated for their immunopotentiating activity on a murine macrophage cell line RAW 264.7.Results: Of the strains, pronounced increases in the levels of nitric oxide(NO), tumor necrosis factor-α and interleukin-6 were observed in strains B0040, B0110 and B0145. Among them,strain B0145 had the highest NO and tumor necrosis factor-α generation in RAW 264.7 cells;strains B0040 and B0110 were also superior to that of Lactobacillus casei. These results demonstrated that NO and cytokines were effectively induced when the bacterial stimulants were treated with macrophages. In addition, strains B0040 and B0110 were identified as Lactobacillus plantarum, and B0145 as Weissella cibaria using 16 S rDNA analysis.Conclusions: The results implicated selected strains may be regarded as a biological response modifier and had a broad application prospects in exploiting new functional food or as a feed additive.

  12. Isolation, enumeration, molecular identification and probiotic potential evaluation of lactic acid bacteria isolated from sheep milk

    L.B. Acurcio

    2014-06-01

    Full Text Available Lactic acid bacteria species were molecularly identified in milk from Lacaune, Santa Inês and crossbred sheep breeds and their in vitro probiotic potential was evaluated. The species identified were Enterococcus faecium (56.25%, E. durans (31.25% and E. casseliflavus (12.5%. No other lactic acid bacteria species, such as lactobacilli, was identified. Most of the isolated enterococci were resistant to gastric pH (2.0 and to 0.3% oxgall. All tested enterococci were resistant to ceftazidime, oxacillin and streptomycin and sensible to clindamycin, erythromycin and penicillin. The resistance to ciprofloxacin, gentamicin, tetracycline and vancomycin varied among tested species. All tested enterococci strongly inhibited (P<0.05 Escherichia coli and Listeria monocytogenes, moderately inhibited E. faecalis and Staphylococcus aureus and did not inhibit Pseudomonas aeruginosa, Salmonella enterica var. Typhimurium and also one E. durans sample isolated from sheep milk. Four samples of E. faecium, one of E. durans and one of E. casseliflavus presented the best probiotic potential.

  13. Chemotactic behavior of deep subsurface bacteria toward carbohydrates, amino acids and a chlorinated alkene

    Lopez de Victoria, G. (Puerto Rico Univ., Rio Piedras (Puerto Rico). Dept. of Biology)

    1989-02-01

    The chemotactic behavior of deep terrestrial subsurface bacteria toward amino acids, carbohydrates and trichloroethylene was assayed using a modification of the capillary method and bacterial enumeration by acridine orange direct counts. Eleven isolates of bacteria isolated from six different geological formations were investigated. A bimodal response rather than an absolute positive or negative response was observed in most assays. Most of the isolates were positively chemotactic to low concentrations of substrates and were repelled by high concentrations of the same substrate. However, this was not the case for trichloroethylene (TCE) which was mostly an attractant and elicited the highest responses in all the isolates when compared with amino acids and carbohydrates. The movement rates of these isolates in aseptic subsurface sediments in the absence and presence of TCE were also determined using a laboratory model. All of the isolates showed distinct response range, peak, and threshold concentrations when exposed to the same substrates suggesting that they are possibly different species as has been inferred from DNA homology studies. 101 refs., 4 figs., 57 tabs.

  14. Comparative Antifungal Effect of Lactic Acid Bacteria Strains on Penicillium digitatum

    Adrian Matei

    2015-11-01

    Full Text Available Lactic acid bacteria (LAB are natural alternative to chemical preservatives for fruits. The aim of the research was to select LAB strains with high antifungal activity against Penicillium digitatum for the biopreservation of fruits. The antifungal activity of eight lactic acid bacteria strains has been evaluated against Penicilliuum digitatum isolated from orange, by overlay assay method and by optical microscope examination. The reversion of inhibition zone after 96 h was recorded as a fungistatic effect while those with inhibition zone for at least 7 days were recorded as fungicidal. The antifungal effect of efficient LAB strains was assessed by comparing inhibition of fungal biofilm formation in liquid media. The strains Lpl, Lpa, LAB 13, LAB 15, LAB 43 and LAB 58 presented intense antifungal activity with clear inhibition zones diameter over 20 mm. The microscopy evidenced atypical hyphae and delaying of conidial chain formation. The strains Lpa, LAB 13, LAB 15 fully inhibited the mycelia growth, strains LAB 43 and LAB 58 partly with delaying of biofilm formation on the surface of culture medium. The results of comparative antifungal activity of LAB strains evidenced the highest inhibition of fungal biofilm formation and structural damages of hyphae and spores caused by the strains Lpa, LAB 13 and LAB 15. These strains could be efficient biocontrol agents of Penicillium digitatum in fruits.

  15. Preparation of metal-resistant immobilized sulfate reducing bacteria beads for acid mine drainage treatment.

    Zhang, Mingliang; Wang, Haixia; Han, Xuemei

    2016-07-01

    Novel immobilized sulfate-reducing bacteria (SRB) beads were prepared for the treatment of synthetic acid mine drainage (AMD) containing high concentrations of Fe, Cu, Cd and Zn using up-flow anaerobic packed-bed bioreactor. The tolerance of immobilized SRB beads to heavy metals was significantly enhanced compared with that of suspended SRB. High removal efficiencies of sulfate (61-88%) and heavy metals (>99.9%) as well as slightly alkaline effluent pH (7.3-7.8) were achieved when the bioreactor was fed with acidic influent (pH 2.7) containing high concentrations of multiple metals (Fe 469 mg/L, Cu 88 mg/L, Cd 92 mg/L and Zn 128 mg/L), which showed that the bioreactor filled with immobilized SRB beads had tolerance to AMD containing high concentrations of heavy metals. Partially decomposed maize straw was a carbon source and stabilizing agent in the initial phase of bioreactor operation but later had to be supplemented by a soluble carbon source such as sodium lactate. The microbial community in the bioreactor was characterized by denaturing gradient gel electrophoresis (DGGE) and sequencing of partial 16S rDNA genes. Synergistic interaction between SRB (Desulfovibrio desulfuricans) and co-existing fermentative bacteria could be the key factor for the utilization of complex organic substrate (maize straw) as carbon and nutrients source for sulfate reduction. PMID:27058913

  16. Sourdough lactic acid bacteria: exploration of non-wheat cereal-based fermentation.

    Coda, Rossana; Cagno, Raffaella Di; Gobbetti, Marco; Rizzello, Carlo Giuseppe

    2014-02-01

    Cereal-based foods represent a very important source of biological as well as of cultural diversity, as testified by the wide range of derived fermented products. A trend that is increasingly attracting bakery industries as well as consumers is the use of non-conventional flours for the production of novel products, characterised by peculiar flavour and better nutritional value. Lactic acid bacteria microbiota of several non-wheat cereals and pseudo-cereals has been recently deeply investigated with the aim of studying the biodiversity and finding starter cultures for sourdough fermentation. Currently, the use of ancient or ethnic grains is mainly limited to traditional typical foods and the bread making process is not well standardised with consequent negative effects on the final properties. The challenge in fermenting such grains is represented by the necessity to combine good technology and sensory properties with nutritional/health benefits. The choice of the starter cultures has a critical impact on the final quality of cereal-based products, and strains that dominate and outcompete contaminants should be applied for specific sourdough fermentations. In this sense, screening and characterisation of the lactic acid bacteria microbiota is very useful in the improvement of a peculiar flour, from both a nutritional and technological point of view. PMID:24230473

  17. Honeybees and beehives are rich sources for fructophilic lactic acid bacteria.

    Endo, Akihito; Salminen, Seppo

    2013-09-01

    Fructophilic lactic acid bacteria (FLAB) are a specific group of lactic acid bacteria (LAB) characterized and described only recently. They prefer fructose as growth substrate and inhabit only fructose-rich niches. Honeybees are high-fructose-consuming insects and important pollinators in nature, but reported to be decreasing in the wild. In the present study, we analyzed FLAB microbiota in honeybees, larvae, fresh honey and bee pollen. A total of 66 strains of LAB were isolated from samples using a selective isolation technique for FLAB. Surprisingly, all strains showed fructophilic characteristics. The 66 strains and ten FLAB strains isolated from flowers in a separate study were genotypically separated into six groups, four of which being identified as Lactobacillus kunkeei and two as Fructobacillus fructosus. One of the L. kunkeei isolates showed antibacterial activity against Melissococcus plutonius, a causative pathogen of European foulbrood, this protection being attributable to production of an antibacterial peptide or protein. Culture-independent analysis suggested that bee products and larvae contained simple Lactobacillus-group microbiota, dominated by L. kunkeei, although adult bees carried a more complex microbiota. The findings clearly demonstrate that honeybees and their products are rich sources of FLAB, and FLAB are potential candidates for future bee probiotics. PMID:23845309

  18. Screening of lactic acid bacteria with high autolysis rate by N+-implantation

    In order to obtain lactic acid bacteria with high autolysis rate, Streptococcus salivarius ssp. thermophilus GS1 and Lactobacillus delbrueckii ssp. bulgaricus LD3 were mutated by 50 keV N+ ions implantation. The results indicated that the survival rate curve took a saddle shape in the range of 1 x 2.6 x 1013 ∼ 6 x 2.6 x 1013 and the total mutation rate was 57% ∼ 74%. The survival rate were 25% ∼ 33% on the suitable dose 4 x 2.6 x 1013 ion/cm2. Among the mutated strains with mutation rate in the range of 127.98% ∼-51.96%, the highest autolysis rate mutation strains were named LD3-A3 and GS1-B13. Compare with original strains, autolysis rates of LD3-A3 and GS1-B13 increased by 127.98% and 115.11% respectively. Fermentation properties of LD3-A3 and GS1-B13 were stable after 5 generation transfer inoculation. It indicates that the ion implantation technique is a feasible method in lactic acid bacteria breeding. (authors)

  19. Molecular diversity of lactic acid bacteria from cassava sour starch (Colombia).

    Omar, N B; Ampe, F; Raimbault, M; Guyot, J P; Tailliez, P

    2000-06-01

    Lactic acid bacteria and more particularly lactobacilli and Leuconostoc, are widely found in a wide variety of traditional fermented foods of tropical countries, made with cereals, tubers, meat or fish. These products represent a source of bacterial diversity that cannot be accurately analysed using classical phenotypic and biochemical tests. In the present work, the identification and the molecular diversity of lactic acid bacteria isolated from cassava sour starch fermentation were assessed by using a combination of complementary molecular methods: Randomly Amplified Polymorphic DNA fingerprinting (RAPD), plasmid profiling, hybridization using rRNA phylogenetic probes and partial 16S rDNA sequencing. The results revealed a large diversity of bacterial species (Lb. manihotivorans, Lb. plantarum, Lb. casei, Lb. hilgardii, Lb. buchneri, Lb. fermentum, Ln. mesenteroides and Pediococcus sp.). However, the most frequently isolated species were Lb. plantarum and Lb. manihotivorans. The RAPD analysis revealed a large molecular diversity between Lb. manihotivorans or Lb. plantarum strains. These results, observed on a rather limited number of samples, reveal that significant bacterial diversity is generated in traditional cassava sour starch fermentations. We propose that the presence of the amylolytic Lb. manihotivorans strains could have a role in sour starch processing. PMID:10930082

  20. Carbonic acid revisited: Vibrational spectra, energetics and the possibility of detecting an elusive molecule

    Stefan E. Huber

    2012-09-01

    Full Text Available We calculate harmonic frequencies of the three most abundant carbonic acid conformers. For this, different model chemistries are investigated with respect to their benefits and shortcomings. Based on these results we use perturbation theory to calculate anharmonic corrections at the ωB97XD/aug-cc-pVXZ, X = D, T, Q, level of theory and compare them with recent experimental data and theoretical predictions. A discrete variable representation method is used to predict the large anharmonic contributions to the frequencies of the stretching vibrations in the hydrogen bonds in the carbonic acid dimer. Moreover, we re-investigate the energetics of the formation of the carbonic acid dimer from its constituents water and carbon dioxide using a high-level extrapolation method. We find that the ωB97XD functional performs well in estimating the fundamental frequencies of the carbonic acid conformers. Concerning the reaction energetics, the accuracy of ωB97XD is even comparable to the high-level extrapolation method. We discuss possibilities to detect carbonic acid in various natural environments such as Earth's and Martian atmospheres.

  1. Acid resistance of methanogenic bacteria in a two-stage anaerobic process treating high concentration methanol Wastewater

    ZHOU Xuefei; REN Nanqi

    2007-01-01

    In this study,the two-stage upflow anaerobic sludge blanket(UASB)system and batch experiments were employed to evaluate the performance of anaerobic digestion for the treatment of high concentration methanol wastewater.The acid resistance of granular sludge and methanogenic bacteria and their metabolizing activity were investigated.The results show that the pH of the first UASB changed from 4.9 to 5.8 and 5.5 to 6.2 for the second reactor.Apparently,these were not the advisable pH levels that common metha nogenic bacteria could accept.The methanogenic bacteria of the system,viz.Methanosarcina barkeri,had some acid resistance and could still degrade methanol at pH 5.0.If the methanogenic bacteria were trained further,their acid resistance would be improved somewhat.Granular sludge of the system could protect the methanogenic bacteria within its body against the impact of the acidic environment and make them degrade methanol at pH 4.5.The performance of granular sludge was attributed to its structure,bacteria species,and the distribution of bacterium inside the granule.

  2. A prebiotic role of Ecklonia cava improves the mortality of Edwardsiella tarda-infected zebrafish models via regulating the growth of lactic acid bacteria and pathogen bacteria.

    Lee, WonWoo; Oh, Jae Young; Kim, Eun-A; Kang, Nalae; Kim, Kil-Nam; Ahn, Ginnae; Jeon, You-Jin

    2016-07-01

    In this study, the beneficial prebiotic roles of Ecklonia cava (E. cava, EC) were evaluated on the growth of lactic acid bacteria (LAB) and pathogen bacteria and the mortality of pathogen-bacteria infected zebrafish model. The result showed that the original E. cava (EC) led to the highest growth effects on three LABs (Lactobacillus brevis, L. brevis; Lactobacillus pentosus, L. pentosus; Lactobacillus plantarum; L. plantarum) and it was dose-dependent manners. Also, EC, its Celluclast enzymatic (ECC) and 100% ethanol extracts (ECE) showed the anti-bacterial activities on the fish pathogenic bacteria such as (Edwardsiella tarda; E. tarda, Streptococcus iniae; S. iniae, and Vibrio harveyi; V. harveyi). Interestingly, EC induced the higher production of the secondary metabolites from L. plantarum in MRS medium. The secondary metabolites produced by EC significantly inhibited the growth of pathogen bacteria. In further in vivo study, the co-treatment of EC and L. plantarum improved the growth and mortality of E. tarda-infected zebrafish as regulating the expression of inflammatory molecules such as iNOS and COX2. Taken together, our present study suggests that the EC plays an important role as a potential prebiotic and has a protective effect against the infection caused by E. tarda injection in zebrafish. Also, our conclusion from this evidence is that EC can be used and applied as a useful prebiotic. PMID:27192145

  3. Lack of inhibitory effects of Lactic acid bacteria on 1,2-dimethylhydrazine-induced colon tumors in rats

    Wei Li; Chong-Bi Li

    2003-01-01

    AIM: A myriad of healthful effects has been attributed to the probiotic lactic acid bacteria, perhaps the most controversial issue remains that of anticancer activity. This study was aimed at investigating the putative anti-cancer effects of lactic acid bacteria strains on the progression of colon tumor in 1,2-dimethylhydrazine (DMH)-treated animals.METHODS: The strain of lactic acid bacteria used in this study was lactic acid bacteria NZ9000 that conformed to the characteristics of plasmid free. Sixty male Wistar rats were given subcutaneous injections of DMH at a dose of 40 mg/kg body wt or saline once a week for 10 weeks. The rats were divided into 6 experimental groups. After the last DMH injection,animals in groups 1 and 4 were gavaged with 1 mi of lactic acid bacteria at a dose of 5×109 per day or vehide until sacrifice at the end of week 22 or week 52. Animals in groups 1-3 were killed at the end of week 22 for histopathological examination.The whole period of experimental observation was 52 weeks.RESULTS: By the end of 22nd week, final average body weights of the rats treated with DMH alone and all animals receiving lactic acid bacteria were significantly decreased compared with the vehicle control (P<0.05). No differences in tumor inridence, multiplicity, dimensions and stage in the colonic mucosa were observed among the groups. At week 52, the survival rate of the rats administered lactic acid bacteria was lower than that of the rats treated with DMH that were fed on control fluids of non-lactococcus lactis. The mean survival time of lactic acid bacteria-treated animals was 39 weeks.CONCLUSION: These results indicate that lactic acid bacteria lacks inhibitory effects on the progression of colon tumor in DMH-treated animals, and does not support the hypothesis that alteration of colonic flora may exert an influence on the progression of colon tumor.

  4. Cholesterol assimilation by lactic acid bacteria and bifidobacteria isolated from the human gut.

    Pereira, Dora I A; Gibson, Glenn R

    2002-09-01

    The objective of this study was to evaluate the effect of human gut-derived lactic acid bacteria and bifidobacteria on cholesterol levels in vitro. Continuous cultures inoculated with fecal material from healthy human volunteers with media supplemented with cholesterol and bile acids were used to enrich for potential cholesterol assimilators among the indigenous bacterial populations. Seven potential probiotics were found: Lactobacillus fermentum strains F53 and KC5b, Bifidobacterium infantis ATCC 15697, Streptococcus bovis ATCC 43143, Enterococcus durans DSM 20633, Enterococcus gallinarum, and Enterococcus faecalis. A comparative evaluation regarding the in vitro cholesterol reduction abilities of these strains along with commercial probiotics was undertaken. The degree of acid and bile tolerance of strains was also evaluated. The human isolate L. fermentum KC5b was able to maintain viability for 2 h at pH 2 and to grow in a medium with 4,000 mg of bile acids per liter. This strain was also able to remove a maximum of 14.8 mg of cholesterol per g (dry weight) of cells from the culture medium and therefore was regarded as a candidate probiotic. PMID:12200334

  5. [Effects of a lactic acid bacteria community SFC-2 treated on rice straw].

    Gao, Li-Juan; Wang, Xiao-Fen; Yang, Hong-Yan; Gao, Xiu-Zhi; Lü, Yu-Cai; Cui, Zong-Jun

    2007-06-01

    Aimed to utilize rice straw and lessen the pressure of environment, the rice straw was used as the fermentation material, and a lactic acid bacteria community SFC-2 from my laboratory was inoculated into the rice straw to investigate the inoculation effects. After 30 days fermentation, the inoculated fermented straw smelt acid-fragrant, and the pH value was 3.8, which was lower than the control of 4.1. Furthermore, lactic acid concentration was more than that in the control. Especially L-lactic acid concentration was two times more than in the control, and the crude protein content was 10.16% higher than that in the control, and the crude fiber content was 3.2% lower than that in the control. From the patterns of denaturing gradient gel electrophoresis (DGGE), Lactobacillus plantarum, Lactobacillus fermentum and Lactobacillus paracasei rapidly became the advantageous species in the inoculated straws. However, Enterobacter sakazakii, Pantoea agglomerans, Enterobacter endosymbiont, Pantoea ananatis, whichwere predominate in the controls, were not detected in the inoculated straws, and the fermented quality was improved significantly. PMID:17674756

  6. Mechanism of gallic acid biosynthesis in bacteria (Escherichia coli) and walnut (Juglans regia).

    Muir, Ryann M; Ibáñez, Ana M; Uratsu, Sandra L; Ingham, Elizabeth S; Leslie, Charles A; McGranahan, Gale H; Batra, Neelu; Goyal, Sham; Joseph, Jorly; Jemmis, Eluvathingal D; Dandekar, Abhaya M

    2011-04-01

    Gallic acid (GA), a key intermediate in the synthesis of plant hydrolysable tannins, is also a primary anti-inflammatory, cardio-protective agent found in wine, tea, and cocoa. In this publication, we reveal the identity of a gene and encoded protein essential for GA synthesis. Although it has long been recognized that plants, bacteria, and fungi synthesize and accumulate GA, the pathway leading to its synthesis was largely unknown. Here we provide evidence that shikimate dehydrogenase (SDH), a shikimate pathway enzyme essential for aromatic amino acid synthesis, is also required for GA production. Escherichia coli (E. coli) aroE mutants lacking a functional SDH can be complemented with the plant enzyme such that they grew on media lacking aromatic amino acids and produced GA in vitro. Transgenic Nicotiana tabacum lines expressing a Juglans regia SDH exhibited a 500% increase in GA accumulation. The J. regia and E. coli SDH was purified via overexpression in E. coli and used to measure substrate and cofactor kinetics, following reduction of NADP(+) to NADPH. Reversed-phase liquid chromatography coupled to electrospray mass spectrometry (RP-LC/ESI-MS) was used to quantify and validate GA production through dehydrogenation of 3-dehydroshikimate (3-DHS) by purified E. coli and J. regia SDH when shikimic acid (SA) or 3-DHS were used as substrates and NADP(+) as cofactor. Finally, we show that purified E. coli and J. regia SDH produced GA in vitro. PMID:21279669

  7. Carbonic Acid Revisited: Critical Remarks on Theoretical Predictions and the Possibility of Detecting an Elusive Molecule

    Huber, Stefan E; Kausch, Wolfgang; Kimeswenger, Stefan; Probst, Michael

    2012-01-01

    We calculate harmonic frequencies of the three most abundant carbonic acid conformers. For this, different model chemistries are investigated with respect to their benefits and shortcomings. Based on these results we use perturbation theory to calculate anharmonic corrections at the {\\omega}B97XD/aug-cc-pVXZ, X=D, T, Q, level of theory and compare them with recent experimental data and theoretical predictions. A discrete variable representation method is used to predict the large anharmonic contributions to the frequencies of the stretching vibrations in the hydrogen bonds in the carbonic acid dimer. Moreover, we re-investigate the energetics of the formation of the carbonic acid dimer from its constituents water and carbon dioxide using a high-level extrapolation method. We find that the {\\omega}B97XD functional performs well in estimating the fundamental frequencies of the carbonic acid conformers. Concerning the reaction energetics, the accuracy of {\\omega}B97XD is even comparable to the high-level extrapo...

  8. Investigation of antibacterial activity of Lactic Acid Bacteria isolated from traditional kordish cheese in comparison with commercial strains

    Fereshteh Tofangsazan

    2013-12-01

    Full Text Available Background and Aim: The health benefits of lactic acid bacteria in human, especially their anti-pathogenic properties has been the focus of recent interests. The objective of this study was to investigate the antibacterial activity of lactic acid bacteria (LAB isolated from traditional Kurdish cheese against a few bacterial pathogens. Materials and Methods: The cell free culture supernatant of LAB isolated from Kurdish cheese which was treated with heat and NaOH were tested for their antibacterial activity by Agar Disk Diffusion method. Moreover, Minimum Inhibition Concentration and Co-aggregation of LAB against pathogens were determined. Each test was repeated for three times. Results: The LAB isolates, in comparison with commercial lactic acid bacteria, showed suitable antibacterial activity. Heating the bacterial supernatant eliminated its anti-bacterial property; however, alkali treatment did not have any effect. The Minimum Inhibition Concentration did not show significant differences between native and commercial lactic acid bacteria; however, the native LAB showed suitable co-aggregation with pathogens. Conclusion: Traditional lactic acid bacteria and their metabolites can inhibit growth of pathogens. This shows the positive role of LAB in human health which necessitates their increase usage as natural antimicrobial agent.

  9. Effect of proteolitic enzymes with probiotic of lactic acid bacteria on characteristics of cow milk dadih

    Miskiyah

    2011-12-01

    Full Text Available Texture of dadih from cow milk tends to be soft, while dadih from buffalo milk have more compact and solid texture. Enzyme is one of food additives that may produce fermented products made from cow milk that has same charcteristic as dadih’s from buffalo milk. Lactic acid bacteria in fermented milk affect product characteristics. This study aimed to determine the effect of combination of enzyme and probiotic lactic acid bacteria on the characteristics of cow's milk dadih. The study was aime designed using completely randomized design (CRD with 9 treatments, A: renin 2 ppm + 3% Lactobacillus casei; B: renin 2 ppm + 3% B. longum; C: renin 2 ppm + 1.5% L. casei + 1.5% B. longum; D: crude extract of Mucor sp. 0.5 ppm + 3% L. casei; E: crude extract of Mucor sp. 0.5 ppm + 3% Brevibacterium longum; F: crude enzyme extract of Mucor sp. 0.5 ppm + 1.5% L. casei + 1.5% B. longum; G: papain 100 ppm + 3% L. casei; H: papain 100 ppm + 3% B. longum; and F: papain 100 ppm + 1.5% L. casei + 1.5% B. longum. Each treatment was repeated two times. Results showed that combination of renin 2 ppm with 3% of L. casei resulted in the best characteristics of cow milk dadih with viscosity 2278 cP; pH 5.63; titrable acidity 0.56%; moisture 75.03%; protein 6.80%; fat 3.35%; carbohydrate 13.21%; LAB total 6.90 x 1010 cfu/g; it also had a flavor, aroma, texture, and general acceptance that mostly preferred by panelists.

  10. Mechanical and acid neutralizing properties and bacteria inhibition of amorphous calcium phosphate dental nanocomposite.

    Moreau, Jennifer L; Sun, Limin; Chow, Laurence C; Xu, Hockin H K

    2011-07-01

    Dental composites do not hinder bacteria colonization and plaque formation. Caries at the restoration margins is a frequent reason for replacement of existing restorations, which accounts for 50 to 70% of all restorations. The objectives of this study were to examine the filler level effect on nanocomposite containing nanoparticles of amorphous calcium phosphate (NACP) and investigate the load-bearing and acid-neutralizing properties and bacteria inhibition. NACP with 116-nm particle size were synthesized via a spray-drying technique and incorporated into a resin. Flexural strength of nanocomposite with 10 to 30% NACP fillers matched the strength of a commercial hybrid composite (p > 0.1). Nanocomposite with 40% NACP matched the strength of a microfill composite, which was 2-fold that of a resin-modified glass ionomer. Nanocomposite with 40% NACP neutralized a lactic acid solution of pH 4 by rapidly increasing the pH to 5.69 in 10 min. In contrast, the commercial controls had pH staying at near 4. Using Streptoccocus mutans, an agar disk-diffusion test showed no inhibition zone for commercial controls. In contrast, the inhibition zone was (2.5 ± 0.7) mm for nanocomposite with 40% NACP. Crystal violet staining showed that S. mutans coverage on nanocomposite was 1/4 that on commercial composite. In conclusion, novel calcium-phosphate nanocomposite matched the mechanical properties of commercial composite and rapidly neutralized lactic acid of pH 4. The nanocomposite appeared to moderately reduce the S. mutans growth, and further study is needed to obtain strong antimicrobial properties. The new nanocomposite may have potential to reduce secondary caries and restoration fracture, two main challenges facing tooth cavity restorations. PMID:21504057

  11. INHIBITION OF STAPHYLOCOCCUS AUREUS BY LACTIC ACID BACTERIA AND / OR BIFIDOBACTERIUM LACTIS DURING MILK FERMENTATION AND STORAGE

    Khalaf S. Al-Delaimy; Yaser M. Hamamdeh

    2013-01-01

    Survival and inhibition of Staphylococcus aureus by the lactic acid bacteria (LAB) starter culture (Sterptococcus thermophillus and Lactobacillus delbrukii subsp. bulgaricus) and/ or probiotic bacteria Bifidobacterium lactis during milk fermentation to yoghurt and storage up to 12 days was studied. Adding S. aureus (initial count log 6.64/ ml) with LAB (initial count log 6.8/ ml) in milk during yoghurt processing and storage resulted in no significant change in the counts of both S. aureus an...

  12. Effect of Growth of Selected Lactic Acid Bacteria on Microbial Flora of Ground Beef under Workshop Conditions

    F. Akbari Nakhjavani; H. Lamea; Sh. Darvishi; F Darvish

    2004-01-01

    The effects of growth of two strains of lactic acid bacteria on microbial flora of ground beef after packaging in air permeable packs were studied under workshop conditions. The strains isolated from dairy products were added to ground beef at a density of 104 CFU/g after identification and antibiosis test against indicator bacteria (Escherichia coli and Staphylococcus aureus). The two strains were Lactobacillus casei subsp. casei 102, and Lactococcus lactis subsp. lactis var. diacetylactis 2...

  13. Scarce Evidence of Yogurt Lactic Acid Bacteria in Human Feces after Daily Yogurt Consumption by Healthy Volunteers

    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...

  14. PCR of crtNM combined with analytical biochemistry : an efficient way to identify carotenoid producing lactic acid bacteria

    Turpin, W.; Renaud, Cécile; Avallone, S.; Hammoumi, A.; Guyot, Jean-Pierre; Humblot, Christèle

    2016-01-01

    Lactic acid bacteria (LAB) synthesize a wide variety of biochemical compounds during food fermentation. Carotenoids provide important biological functions for bacteria, and their consumption by humans has many beneficial effects. In this study, the presence of several genes involved in the production of carotenoids was determined by BLAST analysis and PCR in a collection of 156 LAB isolated from traditional amylaceous African fermented foods. Only the crtE gene and the crtNM operon were prese...

  15. The Biodiversity of Lactic Acid Bacteria in Greek Traditional Wheat Sourdoughs Is Reflected in Both Composition and Metabolite Formation

    De Vuyst, Luc; Schrijvers, Vincent; Paramithiotis, Spiros; Hoste, Bart; Vancanneyt, Marc; Swings, Jean; Kalantzopoulos, George; Tsakalidou, Effie; Messens, Winy

    2002-01-01

    Lactic acid bacteria (LAB) were isolated from Greek traditional wheat sourdoughs manufactured without the addition of baker's yeast. Application of sodium dodecyl sulfate-polyacrylamide gel electrophoresis of total cell protein, randomly amplified polymorphic DNA-PCR, DNA-DNA hybridization, and 16S ribosomal DNA sequence analysis, in combination with physiological traits such as fructose fermentation and mannitol production, allowed us to classify the isolated bacteria into the species Lactob...

  16. Revisiting histidine-dependent acid phosphatases: a distinct group of tyrosine phosphatases

    Veeramani, Suresh; Lee, Ming-Shyue; Lin, Ming-Fong

    2009-01-01

    Although classical protein tyrosine phosphatase (PTP) superfamily members are cysteine-dependent, emerging evidence shows that many acid phosphatases (AcPs) function as histidine-dependent PTPs in vivo. These AcPs dephosphorylate phospho-tyrosine substrates intracellularly and could have roles in development and disease. In contrast to cysteine-dependent PTPs, they utilize histidine, rather than cysteine, for substrate dephosphorylation. Structural analyses reveal that active site histidine, ...

  17. Modelling the effect of lactic acid bacteria from starter- and aroma culture on growth of Listeria monocytogenes in cottage cheese.

    Østergaard, Nina Bjerre; Eklöw, Annelie; Dalgaard, Paw

    2014-10-01

    Four mathematical models were developed and validated for simultaneous growth of mesophilic lactic acid bacteria from added cultures and Listeria monocytogenes, during chilled storage of cottage cheese with fresh- or cultured cream dressing. The mathematical models include the effect of temperature, pH, NaCl, lactic- and sorbic acid and the interaction between these environmental factors. Growth models were developed by combining new and existing cardinal parameter values. Subsequently, the reference growth rate parameters (μref at 25°C) were fitted to a total of 52 growth rates from cottage cheese to improve model performance. The inhibiting effect of mesophilic lactic acid bacteria from added cultures on growth of L. monocytogenes was efficiently modelled using the Jameson approach. The new models appropriately predicted the maximum population density of L. monocytogenes in cottage cheese. The developed models were successfully validated by using 25 growth rates for L. monocytogenes, 17 growth rates for lactic acid bacteria and a total of 26 growth curves for simultaneous growth of L. monocytogenes and lactic acid bacteria in cottage cheese. These data were used in combination with bias- and accuracy factors and with the concept of acceptable simulation zone. Evaluation of predicted growth rates of L. monocytogenes in cottage cheese with fresh- or cultured cream dressing resulted in bias-factors (Bf) of 1.07-1.10 with corresponding accuracy factor (Af) values of 1.11 to 1.22. Lactic acid bacteria from added starter culture were on average predicted to grow 16% faster than observed (Bf of 1.16 and Af of 1.32) and growth of the diacetyl producing aroma culture was on average predicted 9% slower than observed (Bf of 0.91 and Af of 1.17). The acceptable simulation zone method showed the new models to successfully predict maximum population density of L. monocytogenes when growing together with lactic acid bacteria in cottage cheese. 11 of 13 simulations of L

  18. Change in the plasmid copy number in acetic acid bacteria in response to growth phase and acetic acid concentration.

    Akasaka, Naoki; Astuti, Wiwik; Ishii, Yuri; Hidese, Ryota; Sakoda, Hisao; Fujiwara, Shinsuke

    2015-06-01

    Plasmids pGE1 (2.5 kb), pGE2 (7.2 kb), and pGE3 (5.5 kb) were isolated from Gluconacetobacter europaeus KGMA0119, and sequence analyses revealed they harbored 3, 8, and 4 genes, respectively. Plasmid copy numbers (PCNs) were determined by real-time quantitative PCR at different stages of bacterial growth. When KGMA0119 was cultured in medium containing 0.4% ethanol and 0.5% acetic acid, PCN of pGE1 increased from 7 copies/genome in the logarithmic phase to a maximum of 12 copies/genome at the beginning of the stationary phase, before decreasing to 4 copies/genome in the late stationary phase. PCNs for pGE2 and pGE3 were maintained at 1-3 copies/genome during all phases of growth. Under a higher concentration of ethanol (3.2%) the PCN for pGE1 was slightly lower in all the growth stages, and those of pGE2 and pGE3 were unchanged. In the presence of 1.0% acetic acid, PCNs were higher for pGE1 (10 copies/genome) and pGE3 (6 copies/genome) during the logarithmic phase. Numbers for pGE2 did not change, indicating that pGE1 and pGE3 increase their PCNs in response to acetic acid. Plasmids pBE2 and pBE3 were constructed by ligating linearized pGE2 and pGE3 into pBR322. Both plasmids were replicable in Escherichia coli, Acetobacter pasteurianus and G. europaeus, highlighting their suitability as vectors for acetic acid bacteria. PMID:25575969

  19. Antibacterial Activity of Selected Standard Strains of Lactic Acid Bacteria Producing Bacteriocins – Pilot Study

    Malgorzata Bodaszewska-Lubas

    2012-10-01

    Full Text Available  Introduction:In this paper, an attempt was made to evaluate the antibacterial potential of standard strains of lactic acid bacteria (LAB producing bacteriocins of various classes, thus demonstrating various mechanisms of cell membrane damages against the Streptococcus agalactiae strains (Group B Streptococcus, GBS, depending on surface polysaccharides and surface alpha-like protein genes.Materials/Methods:Antimicrobial property of the strains of L. plantarum C 11, L. sakei DSMZ 6333, and L. lactis ATCC 11454 producing bacteriocins: JK and EF plantaricins, sakacin and nisin, respectively, against the GBS strains was evaluated. The chosen to the study GBS strains were represented by serotypes Ia, Ib, II, III, V and they had bca, epsilon, rib, alp2 or alp3 alpha-like protein genes. The experiment was conducted by means of suspension culture and the bacteria count was determined using the serial dilution method.Results:A great ability of L. plantarum C 11 strain was proven to inhibit the GBS growth. The strain of L. sakei DSMZ 6333 did not demonstrate any ability to inhibit the growth of GBS, whereas L. lactis ATCC 11454 inhibited the growth of S. agalactiae indicator strains to a minor extent. Statistically significant differences were demonstrated between the GBS strains representing various serotypes against the antimicrobial activity of model LAB strains. The least sensitive to the activity of bacteriocins were the strains representing serotypes Ib and III, whereas the strains representing serotype II were the most sensitive. The sensitivity of the GBS strains to the antimicrobial activity of LAB was not dependent on alpha-like protein genes.Discussion:Among the LAB standard strains producing bacteriocins, the strongest antimicrobial property was observed in the strain of L. plantarum C 11. Because of the generally known and verified strong antagonistic property of the strains of L. plantarum species against indicator bacteria, it is necessary

  20. Antibiotic resistance of lactic acid bacteria isolated from dry-fermented sausages.

    Fraqueza, Maria João

    2015-11-01

    Dry-fermented sausages are meat products highly valued by many consumers. Manufacturing process involves fermentation driven by natural microbiota or intentionally added starter cultures and further drying. The most relevant fermentative microbiota is lactic acid bacteria (LAB) such as Lactobacillus, Pediococcus and Enterococcus, producing mainly lactate and contributing to product preservation. The great diversity of LAB in dry-fermented sausages is linked to manufacturing practices. Indigenous starters development is considered to be a very promising field, because it allows for high sanitary and sensorial quality of sausage production. LAB have a long history of safe use in fermented food, however, since they are present in human gastrointestinal tract, and are also intentionally added to the diet, concerns have been raised about the antimicrobial resistance in these beneficial bacteria. In fact, the food chain has been recognized as one of the key routes of antimicrobial resistance transmission from animal to human bacterial populations. The World Health Organization 2014 report on global surveillance of antimicrobial resistance reveals that this issue is no longer a future prediction, since evidences establish a link between the antimicrobial drugs use in food-producing animals and the emergence of resistance among common pathogens. This poses a risk to the treatment of nosocomial and community-acquired infections. This review describes the possible sources and transmission routes of antibiotic resistant LAB of dry-fermented sausages, presenting LAB antibiotic resistance profile and related genetic determinants. Whenever LAB are used as starters in dry-fermented sausages processing, safety concerns regarding antimicrobial resistance should be addressed since antibiotic resistant genes could be mobilized and transferred to other bacteria. PMID:26002560

  1. Isolation and identification of lactic acid bacteria from abalone (Haliotis asinina as a potential candidate of probiotic

    YAYAN SOFYAN

    2010-01-01

    Full Text Available Sarkono, Faturrahman, Sofyan Y. 2010. Isolation and identification of lactic acid bacteria from abalone (Haliotis asinina as a potential candidate of probiotic. Nusantara Bioscience 2: 38-42. The purpose of this study was to isolate, select and characterize lactic acid bacteria (LAB from abalone as a potential candidate probiotic in abalone cultivation system. Selective isolation of LAB performed using de Man Rogosa Sharpe medium. LAB isolate that potential as probiotics was screened. Selection was based on its ability to suppress the growth of pathogenic bacteria, bacterial resistance to acidic conditions and bacterial resistance to bile salts (bile. Further characterization and identification conducted to determine the species. The results showed that two of the ten isolates potential to be developed as probiotic bacteria that have the ability to inhibit several pathogenic bacteria such as Eschericia coli, Bacillus cereus dan Staphylococus aureus, able to grow at acidic condition and bile tolerance during the incubation for 24 hour. Based on the API test kit, the both of isolate identified as members of the species Lactobacillus paracasei ssp. paracasei.

  2. Production of extracellular nucleic acids by genetically altered bacteria in aquatic-environment microcosms

    The factors which affect the production of extracellular DNA by genetically altered strains of Escherichia coli, Pseudomonas aeruginosa, Pseudomonas cepacia, and Bradyrhizobium japonicum in aquatic environments were investigated. Cellular nucleic acids were labeled in vivo by incubation with [3H]thymidine or [3H]adenine, and production of extracellular DNA in marine waters, artificial seawater, or minimal salts media was determined by detecting radiolabeled macromolecules in incubation filtrates. The presence or absence of the ambient microbial community had little effect on the production of extracellular DNA. Three of four organisms produced the greatest amounts of extracellular nucleic acids when incubated in low-salinity media (2% artificial seawater) rather than high-salinity media (10 to 50% artificial seawater). The greatest production of extracellular nucleic acids by P. cepacia occurred at pH 7 and 37 degree C, suggesting that extracellular-DNA production may be a normal physiologic function of the cell. Incubation of labeled P. cepacia cells in water from Bimini Harbor, Bahamas, resulted in labeling of macromolecules of the ambient microbial population. Collectively these results indicate that (i) extracellular-DNA production by genetically altered bacteria released into aquatic environments is more strongly influenced by physicochemical factors than biotic factors, (ii) extracellular-DNA production rates are usually greater for organisms released in freshwater than marine environments, and (iii) ambient microbial populations can readily utilize materials released by these organisms

  3. Comparison of homo- and heterofermentative lactic acid bacteria for implementation of fermented wheat bran in bread.

    Prückler, Michael; Lorenz, Cindy; Endo, Akihito; Kraler, Manuel; Dürrschmid, Klaus; Hendriks, Karel; Soares da Silva, Francisco; Auterith, Eric; Kneifel, Wolfgang; Michlmayr, Herbert

    2015-08-01

    Despite its potential health benefits, the integration of wheat bran into the food sector is difficult due to several adverse technological and sensory properties such as bitterness and grittiness. Sourdough fermentation is a promising strategy to improve the sensory quality of bran without inducing severe changes to the bran matrix. Therefore, identification of species/strains with potential for industrial sourdough fermentations is important. We compared the effects of different representatives of species of lactic acid bacteria (LAB) on wheat bran. Lactobacillus plantarum, Lactobacillus pentosus, Lactobacillus brevis, Lactobacillus sanfranciscensis and Fructobacillus fructosus produced highly individual fermentation patterns as judged from carbohydrate consumption and organic acid production. Interestingly, fructose was released during all bran fermentations and possibly influenced the fermentation profiles of obligately heterofermentative species to varying degrees. Except for the reduction of ferulic acid by L. plantarum and L. pentosus, analyses of phenolic compounds and alkylresorcinols suggested that only minor changes thereof were induced by the LAB metabolism. Sensory analysis of breads baked with fermented bran did not reveal significant differences regarding perceived bitterness and aftertaste. We conclude that in addition to more traditionally used sourdough species such as L. sanfranciscensis and L. brevis, also facultatively heterofermentative species such as L. plantarum and L. pentosus possess potential for industrial wheat bran fermentations and should be considered in further investigations. PMID:25846933

  4. Detection of Sialic Acid-Utilising Bacteria in a Caecal Community Batch Culture Using RNA-Based Stable Isotope Probing

    Wayne Young

    2015-03-01

    Full Text Available Sialic acids are monosaccharides typically found on cell surfaces and attached to soluble proteins, or as essential components of ganglioside structures that play a critical role in brain development and neural transmission. Human milk also contains sialic acid conjugated to oligosaccharides, glycolipids, and glycoproteins. These nutrients can reach the large bowel where they may be metabolised by the microbiota. However, little is known about the members of the microbiota involved in this function. To identify intestinal bacteria that utilise sialic acid within a complex intestinal community, we cultured the caecal microbiota from piglets in the presence of 13C-labelled sialic acid. Using RNA-based stable isotope probing, we identified bacteria that consumed 13C-sialic acid by fractionating total RNA in isopycnic buoyant density gradients followed by 16S rRNA gene analysis. Addition of sialic acid caused significant microbial community changes. A relative rise in Prevotella and Lactobacillus species was accompanied by a corresponding reduction in the genera Escherichia/Shigella, Ruminococcus and Eubacterium. Inspection of isotopically labelled RNA sequences suggests that the labelled sialic acid was consumed by a wide range of bacteria. However, species affiliated with the genus Prevotella were clearly identified as the most prolific users, as solely their RNA showed significantly higher relative shares among the most labelled RNA species. Given the relevance of sialic acid in nutrition, this study contributes to a better understanding of their microbial transformation in the intestinal tract with potential implications for human health.

  5. Lactic acid bacteria--20 years exploring their potential as live vectors for mucosal vaccination.

    Wyszyńska, Agnieszka; Kobierecka, Patrycja; Bardowski, Jacek; Jagusztyn-Krynicka, Elżbieta Katarzyna

    2015-04-01

    Lactic acid bacteria (LAB) are a diverse group of Gram-positive, nonsporulating, low G + C content bacteria. Many of them have been given generally regarded as safe status. Over the past two decades, intensive genetic and molecular research carried out on LAB, mainly Lactococcus lactis and some species of the Lactobacillus genus, has revealed new, potential biomedical LAB applications, including the use of LAB as adjuvants, immunostimulators, or therapeutic drug delivery systems, or as factories to produce therapeutic molecules. LAB enable immunization via the mucosal route, which increases effectiveness against pathogens that use the mucosa as the major route of entry into the human body. In this review, we concentrate on the encouraging application of Lactococcus and Lactobacillus genera for the development of live mucosal vaccines. First, we present the progress that has recently been made in the field of developing tools for LAB genetic manipulations, which has resulted in the successful expression of many bacterial, parasitic, and viral antigens in LAB strains. Next, we discuss the factors influencing the efficacy of the constructed vaccine prototypes that have been tested in various animal models. Apart from the research focused on an application of live LABs as carriers of foreign antigens, a lot of work has been recently done on the potential usage of nonliving, nonrecombinant L. lactis designated as Gram-positive enhancer matrix (GEM), as a delivery system for mucosal vaccination. The advantages and disadvantages of both strategies are also presented. PMID:25750046

  6. Growth of bacteria on 3-nitropropionic acid as a sole source of carbon, nitrogen, and energy.

    Nishino, Shirley F; Shin, Kwanghee A; Payne, Rayford B; Spain, Jim C

    2010-06-01

    3-Nitropropionic acid (3NPA) is a widespread nitroaliphatic toxin found in a variety of legumes and fungi. Several enzymes have been reported that can transform the compound, but none led to the mineralization of 3NPA. We report here the isolation of bacteria that grow on 3NPA and its anion, propionate-3-nitronate (P3N), as the sole source of carbon, nitrogen, and energy. Experiments with resting cells, cell extracts, and purified enzymes indicate that the pathway involves conversion of 3NPA to P3N, which upon denitration yields malonic semialdehyde, nitrate, nitrite, and traces of H(2)O(2). Malonic semialdehyde is decarboxylated to acetyl coenzyme A. The gene that encodes the enzyme responsible for the denitration of P3N was cloned and expressed, and the enzyme was purified. Stoichiometry of the reaction indicates that the enzyme is a monooxygenase. The gene sequence is related to a large group of genes annotated as 2-nitropropane dioxygenases, but the P3N monooxygenase and closely related enzymes form a cluster within COG2070 that differs from previously characterized 2-nitropropane dioxygenases by their substrate specificities and reaction products. The results suggest that the P3N monooxygenases enable bacteria to exploit 3NPA in natural habitats as a growth substrate. PMID:20382807

  7. Chitosan-hyaluronic acid/nano silver composite sponges for drug resistant bacteria infected diabetic wounds.

    Anisha, B S; Biswas, Raja; Chennazhi, K P; Jayakumar, R

    2013-11-01

    The aim of this work was to develop an antimicrobial sponge composed of chitosan, hyaluronic acid (HA) and nano silver (nAg) as a wound dressing for diabetic foot ulcers (DFU) infected with drug resistant bacteria. nAg (5-20 nm) was prepared and characterized. The nanocomposite sponges were prepared by homogenous mixing of chitosan, HA and nAg followed by freeze drying to obtain a flexible and porous structure. The prepared sponges were characterized using SEM and FT-IR. The porosity, swelling, biodegradation and haemostatic potential of the sponges were also studied. Antibacterial activity of the prepared sponges was analysed using Escherichia coli, Staphylococcus aureus, methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa and Klebsiella pneumonia. Chitosan-HA/nAg composite sponges showed potent antimicrobial property against the tested organisms. Sponges containing higher nAg (0.005%, 0.01% and 0.02%) concentrations showed antibacterial activity against MRSA. Cytotoxicity and cell attachment studies were done using human dermal fibroblast cells. The nanocomposite sponges showed a nAg concentration dependent toxicity towards fibroblast cells. Our results suggest that this nanocomposite sponges could be used as a potential material for wound dressing for DFU infected with antibiotic resistant bacteria if the optimal concentration of nAg exhibiting antibacterial action with least toxicity towards mammalian cells is identified. PMID:24060281

  8. Lactic acid bacteria from "Sheep's Dhan", a traditional butter: Isolation, identification and major technological traits

    2009-06-01

    Full Text Available Twenty six lactic acid bacteria were isolated from sheep’s Dhan, a traditional butter made from sheep’s milk in Jijel (East of Algeria. These strains belong to three genera: Lactococcus, Leuconostoc and Lactobacillus. The results showed that Lactococcus lactis ssp diacetylactis was the predominant species in this traditional butter. The results of the assessment of the technological aptitude indicate that a major strain has a good acidification aptitude, some of them show good proteolytic activity and only Leuconostoc mesenteroides ssp. dextranicum isolates were able to produce exopolysaccharide.

    Veintiséis bacterias lácticas fueron aisladas de “Sheep´s Dhan”, una mantequilla tradicional hecha con leche de oveja en Jijel (al Este de Argelia. Estas cepas pertenecen a tres géneros: Lactococcus, Leuconostoc y Lactobacillus. Los resultados mostraron que Lactococcus lactis ssp diacetylactis fue la especie predominante en esta mantequilla tradicional. Los resultados de la evaluación de la aptitud tecnológica indican que la principal cepa tiene una buena aptitud de acidificación, algunas de ellas mostraron una buena actividad proteolítica y únicamente Leuconostoc mesenteroides ssp. dextranicum fue capaz de producir exopolisacárido.

  9. Lactic acid bacteria: reviewing the potential of a promising delivery live vector for biomedical purposes.

    Cano-Garrido, Olivia; Seras-Franzoso, Joaquin; Garcia-Fruitós, Elena

    2015-01-01

    Lactic acid bacteria (LAB) have a long history of safe exploitation by humans, being used for centuries in food production and preservation and as probiotic agents to promote human health. Interestingly, some species of these Gram-positive bacteria, which are generally recognized as safe organisms by the US Food and Drug Administration (FDA), are able to survive through the gastrointestinal tract (GIT), being capable to reach and colonize the intestine, where they play an important role. Besides, during the last decades, an important effort has been done for the development of tools to use LAB as microbial cell factories for the production of proteins of interest. Given the need to develop effective strategies for the delivery of prophylactic and therapeutic molecules, LAB have appeared as an appealing option for the oral, intranasal and vaginal delivery of such molecules. So far, these genetically modified organisms have been successfully used as vehicles for delivering functional proteins to mucosal tissues in the treatment of many different pathologies including GIT related pathologies, diabetes, cancer and viral infections, among others. Interestingly, the administration of such microorganisms would suppose a significant decrease in the production cost of the treatments agents since being live organisms, such vectors would be able to autonomously amplify and produce and deliver the protein of interest. In this context, this review aims to provide an overview of the use of LAB engineered as a promising alternative as well as a safety delivery platform of recombinant proteins for the treatment of a wide range of diseases. PMID:26377321

  10. Selection of enhanced antimicrobial activity posing lactic acid bacteria characterised by (GTG)5-PCR fingerprinting.

    Šalomskienė, Joana; Abraitienė, Asta; Jonkuvienė, Dovilė; Mačionienė, Irena; Repečkienė, Jūratė

    2015-07-01

    The aim of the study was a detail evaluation of genetic diversity among the lactic acid bacteria (LAB) strains having an advantage of a starter culture in order to select genotypically diverse strains with enhanced antimicrobial effect on some harmfull and pathogenic microorganisms. Antimicrobial activity of LAB was performed by the agar well diffusion method and was examined against the reference strains and foodborne isolates of Bacillus cereus, Listeria monocytogenes, Escherichia coli, Staphylococcus aureus and Salmonella Typhimurium. Antifungal activity was tested against the foodborne isolates of Candida parapsilosis, Debaromyces hansenii, Kluyveromyces marxianus, Pichia guilliermondii, Yarowia lipolytica, Aspergillus brasiliensis, Aspergillus versicolor, Cladosporium herbarum, Penicillium chrysogenum and Scopulariopsis brevicaulis. A total 40 LAB strains representing Lactobacillus (23 strains), Lactococcus (13 strains) and Streptococcus spp. (4 strains) were characterised by repetitive sequence based polymerase chain reaction fingerprinting which generated highly discriminatory profiles, confirmed the identity and revealed high genotypic heterogeneity among the strains. Many of tested LAB demonstrated strong antimicrobial activity specialised against one or few indicator strains. Twelve LAB strains were superior in suppressing growth of the whole complex of pathogenic bacteria and fungi. These results demonstrated that separate taxonomic units offered different possibilities of selection for novel LAB strains could be used as starter cultures enhancing food preservation. PMID:26139877

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

    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.

  12. Chasing bacteria within the cells using levofloxacin-loaded hyaluronic acid nanohydrogels.

    Montanari, E; D'Arrigo, G; Di Meo, C; Virga, A; Coviello, T; Passariello, C; Matricardi, P

    2014-08-01

    In the present work, an innovative approach based on the delivery of levofloxacin (LVF) from polysaccharide nanohydrogels for the treatment of bacterial intracellular infections is described. The nanohydrogels (NHs) were obtained by self-assembling of the hyaluronic acid-cholesterol amphiphilic chains in aqueous environment. LVF, a fluoroquinolone antibiotic scarcely efficient in intracellular infections, was entrapped within such NHs by nanoprecipitation, thus forming a drug delivery system (LVF-NHs) that was tested for its activity on different bacteria strains. The MIC values of levofloxacin-loaded nanohydrogels were determined for Staphylococcus aureus and Pseudomonas aeruginosa strains and compared to those obtained using free LVF. The intracellular antimicrobial activity of LVF-NHs and free LVF was compared on HeLa epithelial cell line infected by the above mentioned bacteria, and the increase in antibacterial efficacy of LVF-NHs with respect to that of free LVF was evidenced. The obtained results allow to conclude that this new approach can be considered as really promising method for intracellular infection treatments. PMID:24642185

  13. Fluorescent reporter systems for tracking probiotic lactic acid bacteria and bifidobacteria.

    Landete, José M; Medina, Margarita; Arqués, Juan L

    2016-07-01

    In the last two decades, there has been increasing evidence supporting the role of the intestinal microbiota in health and disease, as well as the use of probiotics to modulate its activity and composition. Probiotic bacteria selected for commercial use in foods, mostly lactic acid bacteria and bifidobacteria, must survive in sufficient numbers during the manufacturing process, storage, and passage through the gastro-intestinal tract. They have several modes of action and it is crucial to unravel the mechanisms underlying their postulated beneficial effects. To track their survival and persistence, and to analyse their interaction with the gastro-intestinal epithelia it is essential to discriminate probiotic strains from endogenous microbiota. Fluorescent reporter proteins are relevant tools that can be exploited as a non-invasive marker system for in vivo real-time imaging in complex ecosystems as well as in vitro fluorescence labelling. Oxygen is required for many of these reporter proteins to fluoresce, which is a major drawback in anoxic environments. However, some new fluorescent proteins are able to overcome the potential problems caused by oxygen limitations. The current available approaches and the benefits/disadvantages of using reporter vectors containing fluorescent proteins for labelling of bacterial probiotic species commonly used in food are addressed. PMID:27263014

  14. The evolution of lactic acid bacteria community during the development of mature sourdough

    Savić Dragiša S.

    2009-01-01

    Full Text Available In order to follow the composition and changes in lactic acid bacteria (LAB population of rye flour sourdough that was continuously propagated by a repeated inoculation, sixty-two strains of LAB were isolated and characterized. The LAB were the only bacteria detected, both at the end of the second propagation step and in the stage of mature sourdough (after two weeks of continuous daily refreshment. The stable ecological system in rye sourdough could be established from the second propagation step onward. The predominant genera of LAB during the development of sourdough were lactobacilli, which were grouped in eight clusters. Heterofermentative lactobacilli were in majority in both propagation step two and a mature sourdough participating 56% and 70% of total bacterial count, respectively. The identification based on a phenotypic characterization that was carried out by using a set of 36 tests, showed that the lactobacilli contained in the two sourdough steps did not clearly belong to any known species of the genus Lactobacillus. In addition, the structure of the bacterial population were monitored by two statistical techniques (Hierachical Cluster Analysis and Principal Component Analysis, being applied to phenotypical characteristics of the isolates.

  15. Biotechnology and pasta-making: Lactic Acid Bacteria as a new driver of innovation

    Vittorio eCapozzi

    2012-03-01

    Full Text Available Cereals-derived foods represent a key constituent in the diet of many populations. In particular, pasta is consumed in large quantities throughout the world in reason of its nutritive importance, containing significant amounts of complex carbohydrates, proteins, B-vitamins, and iron. Lactic acid bacteria (LAB are a heterogeneous group of bacteria that play a key role in the production of fermented foods and beverages with high relevance for human and animal health. A wide literature testifies the multifaceted importance of LAB biotechnological applications in cereal-based products. Several studies focused on LAB isolation and characterization in durum wheat environment, in some cases with preliminary experimental applications of LAB in pasta-making. In this paper, using sourdough as a model, we focus on the relevant state-of-art to introduce a LAB-based biotechnological step in industrial pasta-making, a potential world driver of innovation that might represent a cutting-edge advancement in pasta production.

  16. PENAMBAHAN BAKTERI ASAM LAKTAT TERENKAPSULASI UNTUK MENEKAN PERTUMBUHAN BAKTERI PATOGEN PADA PROSES PRODUKSI TAPIOKA [Addition of Encapsulated Lactic Acid Bacteria to Suppress the Growth of Pathogenic Bacteria during Tapioca Production

    Glisina Dwinoor Rembulan

    2015-07-01

    Full Text Available Lactic acid bacteria (LAB produce organic acids and active compounds which can inhibit the growth of pathogenic bacteria. Lactic acid bacteria potentially can be introduced to inhibit pathogenic bacteria in the tapioca production at the extraction stage, especially during the settling process since there is possibility of starch slurry to be contaminated by pathogenic bacteria from water. The objectives of this research were to design a solid starter of LAB through encapsulation by using modified starch includes sour cassava starch, lintnerized cassava starch and nanocrystalline starch, utilize the starter for suppressing the growth of pathogenic bacteria in the production process of tapioca and characterize the functional properties of tapioca. The encapsulation of lactic acid bacteria was conducted by freeze drying at a temperature of -50°C for 48 hours. The viability of LAB after freeze drying with sour cassava starch matrix was 92% of the liquid starter, with lintnerized cassava starch matrix was 93%, while that with nanocrystalline matrix was 96%. After application of the LAB culture during settling process for tapioca extraction and the tapioca was stored at room temperature for 6 months, it was shown that E. coli, Salmonella and Shigella were  detected in the native tapioca starch (without treatment while the starch added with lactic acid bacteria starter was not absent for the pathogenic bacteria. The addition of lactic acid bacteria in extraction process can suppress the growth of pathogenic bacteria in tapioca. The results showed that lintnerized cassava starch matrix is the best matrix because after 6 months it still contained lactic acid bacteria as compared to liquid starter and that encapsulated with other matrixes.

  17. Medical and Personal Care Applications of Bacteriocins Produced by Lactic Acid Bacteria

    Dicks, L. M. T.; Heunis, T. D. J.; van Staden, D. A.; Brand, A.; Noll, K. Sutyak; Chikindas, M. L.

    The frequent use of antibiotics has led to a crisis in the antibiotic ­resistance of pathogens associated with humans and animals. Antibiotic resistance and the emergence of multiresistant bacterial pathogens have led to the investigation of alternative antimicrobial agents to treat and prevent infections in both humans and animals. Research on antimicrobial peptides, with a special interest on bacteriocins of lactic acid bacteria, is entering a new era with novel applications other than food preservation. Many scientists are now focusing on the application of these peptides in medicinal and personal care products. However, it is difficult to assess the success of such ventures due to the dearth of information that has been published and the lack of clinical trials.

  18. Comparative analysis of antimicrobial and proteolytic activity of lactic acid bacteria isolated from Zlatar cheese

    Topisirović Ljubiša

    2007-01-01

    Full Text Available Traditional artisan Zlatar cheese belongs to the group of white, semi hard home-made cheeses, which are produced from no pasteurized cow's milk, without addition of any known bacterial starter culture. In total, 253 Gram-positive and catalase negative lactic acid bacteria (LAB were isolated. Results showed that 70 out of 253 analyzed isolates produced antimicrobial compounds known as bacteriocins. Most isolates from genera Lactococcus and Enterococcus, and isolates belonging to species Lactobacillus plantarum and Lb. brevis, do not synthesize extracellular proteinase. In contrast, isolates from subspecies Lb. paracasei subsp. paracasei showed very good proteolytic activity. It was observed that good proteolytic activity of isolates was not in correlation with their good antimicrobial activity in the most of isolates.

  19. Utilization of Vinegar for Isolation of Cellulose Producing Acetic Acid Bacteria

    Wastes of traditionally fermented Turkish vinegar were used in the isolation of cellulose producing acetic acid bacteria. Waste material was pre-enriched in Hestrin-Schramm medium and microorganisms were isolated by plating dilution series on HS agar plates The isolated strains were subjected to elaborate biochemical and physiological tests for identification. Test results were compared to those of reference strains Gluconacetobacter xylinus DSM 46604, Gluconacetobacter hansenii DSM 5602 and Gluconacetobacter liquefaciens DSM 5603. Seventeen strains, out of which only three were found to secrete the exopolysaccharide cellulose. The highest cellulose yield was recorded as 0.263±0.02 g cellulose L-1 for the strain AS14 which resembled Gluconacetobacter hansenii in terms of biochemical tests.

  20. Inhibition of mycotoxin-producing Aspergillus nomius vsc 23 by lactic acid bacteria and Saccharomyces cerevisiae

    R Muñoz

    2010-12-01

    Full Text Available The effect of different fermenting microorganisms on growth of a mycotoxin- producing Aspergillus nomius was assayed. Two lactic acid bacteria, Lactobacillus fermentum and Lactobacillus rhamnosus, and Saccharomyces cerevisiae, all of which are widely used in fermentation and preservation of food, were assayed on their fungus inhibitory properties. Assays were carried out by simultaneous inoculation of one of the possible inhibiting microorganisms and the fungus or subsequent inoculation of one of the microorganisms followed by the fungus. All three microorganisms assayed showed growth inhibition of the mycotoxin-producing Aspergillus strain. L. rhamnosus O236, isolated from sheep milk and selected for its technological properties, showed highest fungal inhibition of the microorganisms assayed. The use of antifungal LAB with excellent technological properties rather than chemical preservatives would enable the food industry to produce organic food without addition of chemical substances.

  1. Technological and safety properties of lactic acid bacteria isolated from Spanish dry-cured sausages.

    Landeta, G; Curiel, J A; Carrascosa, A V; Muñoz, R; de las Rivas, B

    2013-10-01

    Technological and safety-related properties were analyzed in lactic acid bacteria isolated from Spanish dry-cured sausages in order to select them as starter cultures. In relation to technological properties, all the strains showed significative nitrate reductase activity; Lactobacillus plantarum, Lactobacillus paracasei and 52% of the Enterococcus faecium strains showed lipolytic activity and only Lactobacillus sakei strains (43%) were able to form biofilms. Related to safety aspects, E. faecium strains were the most resistant to antibiotics, whereas, L. sakei strains were the most sensitive. In relation to virulence factors, in the E. faecium strains analyzed, only the presence of efaA gene was detected. The analysis of biogenic amine production showed that most E. faecium strains and L. sakei Al-142 produced tyramine. In conclusion, L. paracasei Al-128 and L. sakei Al-143 strains possess the best properties to be selected as adequate and safe meat starter cultures. PMID:23743032

  2. Inhibition of mycotoxin-producing Aspergillus nomius vsc 23 by lactic acid bacteria and Saccharomyces cerevisiae.

    Muñoz, R; Arena, M E; Silva, J; González, S N

    2010-10-01

    The effect of different fermenting microorganisms on growth of a mycotoxin- producing Aspergillus nomius was assayed. Two lactic acid bacteria, Lactobacillus fermentum and Lactobacillus rhamnosus, and Saccharomyces cerevisiae, all of which are widely used in fermentation and preservation of food, were assayed on their fungus inhibitory properties. Assays were carried out by simultaneous inoculation of one of the possible inhibiting microorganisms and the fungus or subsequent inoculation of one of the microorganisms followed by the fungus. All three microorganisms assayed showed growth inhibition of the mycotoxin-producing Aspergillus strain. L. rhamnosus O236, isolated from sheep milk and selected for its technological properties, showed highest fungal inhibition of the microorganisms assayed. The use of antifungal LAB with excellent technological properties rather than chemical preservatives would enable the food industry to produce organic food without addition of chemical substances. PMID:24031582

  3. Mucosal targeting of therapeutic molecules using genetically modified lactic acid bacteria: an update.

    LeBlanc, Jean Guy; Aubry, Camille; Cortes-Perez, Naima G; de Moreno de LeBlanc, Alejandra; Vergnolle, Nathalie; Langella, Philippe; Azevedo, Vasco; Chatel, Jean-Marc; Miyoshi, Anderson; Bermúdez-Humarán, Luis G

    2013-07-01

    Lactic acid bacteria (LAB) represent a heterogeneous group of microorganisms naturally present in many foods and those have proved to be effective mucosal delivery vectors. Moreover, some specific strains of LAB exert beneficial properties (known as probiotic effect) on both human and animal health. Although probiotic effects are strain-specific traits, it is theoretically possible, using genetic engineering techniques, to design strains that can exert a variety of beneficial properties. During the two past decades, a large variety of therapeutic molecules has been successfully expressed in LAB, and although this field has been largely reviewed in recent years, approximately 20 new publications appear each year. Thus, the aim of this minireview is not to extensively assess the entire literature but to update progress made within the last 2 years regarding the use of the model LAB Lactococcus lactis and certain species of lactobacilli as live recombinant vectors for the development of new safe mucosal vaccines. PMID:23600579

  4. PROTEOLYTIC AND FIBRINOLYTIC ACTIVITIES OF HALOPHILIC LACTIC ACID BACTERIA FROM TWO INDONESIAN FERMENTED FOODS

    Asep A. Prihanto

    2013-04-01

    Full Text Available Exploration of fermented foods as sources of fibrinolytic enzymes is increased in the last decades. Terasi and Jambal roti is Indonesian traditional fermented fish products, which were famous in Java Island. Both are important products in Indonesian dishes, especially in Java. Investigation on halophilic lactic acid bacteria using MRS and M-17 agar obtained seventy four isolated strains. Their proteolytic and fibrinolytic activities were determined using skim milk agar and plasminogen-free fibrin plate. Twenty five isolates showed protease activities, while only four of them secreted fibrinolitic enzyme. The highest proteolytic and fibrinolytic activity was shown by TB1 strain, which is identified as Bacillus coagulans. The 16s rDNA is still in investigating to confirm the TB1 strain identity.

  5. Production of bacteriocin-like substances by lactic acid bacteria isolated from regional ovine cheese

    Cássia Regina Nespolo

    2010-12-01

    Full Text Available Lactic acid bacteria (LAB were isolated from ovine milk and cheeses manufactured in the South Region of Brazil. Among 112 bacterial isolates investigated, 59 were chosen through a screening for LAB. Among these 59 strains of LAB, 21% showed antimicrobial, proteolytic and lipolytic activities. Based on this screening, Lactobacillus plantarum LCN 17 and Lactobacillus rhamnosus LCN 43 were selected and tested for the production of bacteriocin-like substances (BLS. The BLS produced by both isolates showed antimicrobial activity against Listeria monocytogenes, whereas that produced by L. plantarum LCN 17 presented higher stability to different temperature, pH and enzyme treatments. These strains present potential for production of BLS, and for use as starter cultures.

  6. Analysis of the lactic acid bacteria microflora in traditional Caucasus cow's milk cheeses

    Terzić-Vidojević Amarela

    2009-01-01

    Full Text Available A total of 157 lactic acid bacteria (LAB were isolated from three hand-made cheeses taken from different households in the region of the Caucasus Mountains. The cheeses were manufactured from cow's milk without the addition of a starter culture. The isolates of LAB were characterized by subjecting them to phenotypic and genotypic tests. The results of identification of LAB indicate that the examined cheeses contained 10 species, viz., Lactobacillus plantarum, Lactobacillus paraplantarum, Lactobacillus arizonensis, Lactobacillus farciminis, Lactobacillus brevis, Lactococcus lactis subsp. lactis, Leuconostoc mesenteroides subsp. mesenteroides, Leuconostoc pseudomesenteroides, Enterococcus faecium, and Enterococcus faecalis. The strains within the species L. plantarum, L. arizonensis, L. paraplantarum, L. farciminis, and L. pseudomesenteroides showed good proteolytic activity.

  7. Perspectives on the probiotic potential of lactic acid bacteria from African traditional fermented foods and beverages.

    Mokoena, Mduduzi Paul; Mutanda, Taurai; Olaniran, Ademola O

    2016-01-01

    Diverse African traditional fermented foods and beverages, produced using different types of fermentation, have been used since antiquity because of their numerous nutritional values. Lactic acid bacteria (LAB) isolated from these products have emerged as a welcome source of antimicrobials and therapeutics, and are accepted as probiotics. Probiotics are defined as live microbial food supplements which beneficially affect the host by improving the intestinal microbial balance. Currently, popular probiotics are derived from fermented milk products. However, with the growing number of consumers with lactose intolerance that are affected by dietary cholesterol from milk products, there is a growing global interest in probiotics from other food sources. The focus of this review is to provide an overview of recent developments on the applications of probiotic LAB globally, and to specifically highlight the suitability of African fermented foods and beverages as a viable source of novel probiotics. PMID:26960543

  8. In vitro competitive adhesion and production of antagonistic compounds by lactic acid bacteria against fish pathogens.

    Balcázar, José Luis; Vendrell, Daniel; de Blas, Ignacio; Ruiz-Zarzuela, Imanol; Gironés, Olivia; Múzquiz, José Luis

    2007-06-21

    The present study describes the screening of five lactic acid bacteria (LAB) for use as probiotics based on their competitive adhesion and production of antagonistic substances against some fish pathogens. A reduction of adhesion of all pathogenic strains tested was obtained with three of the LAB strains (Lactococcus lactis subsp. lactis CLFP100, Lactococcus lactis subsp. cremoris CLFP102 and Lactobacillus curvatus CLFP150). With the exception of fish pathogens Flavobacterium psychrophilum and Renibacterium salmoninarum that were not inhibited by LAB strains, production of antagonistic compounds by all tested LAB was observed against at least one of the indicator strains. Based on mucus adhesion, competitive exclusion, and suppression of fish pathogen growth, the selected LAB strains can be considered for future challenge experiments in fish as a very promising alternative to the use of chemotherapeutic agents. PMID:17336468

  9. Utilization of Vinegar for Isolation of Cellulose Producing Acetic Acid Bacteria

    Aydin, Y. Andelib; Aksoy, Nuran Deveci

    2010-06-01

    Wastes of traditionally fermented Turkish vinegar were used in the isolation of cellulose producing acetic acid bacteria. Waste material was pre-enriched in Hestrin-Schramm medium and microorganisms were isolated by plating dilution series on HS agar plates The isolated strains were subjected to elaborate biochemical and physiological tests for identification. Test results were compared to those of reference strains Gluconacetobacter xylinus DSM 46604, Gluconacetobacter hansenii DSM 5602 and Gluconacetobacter liquefaciens DSM 5603. Seventeen strains, out of which only three were found to secrete the exopolysaccharide cellulose. The highest cellulose yield was recorded as 0.263±0.02 g cellulose L-1 for the strain AS14 which resembled Gluconacetobacter hansenii in terms of biochemical tests.

  10. Perspectives on the probiotic potential of lactic acid bacteria from African traditional fermented foods and beverages

    Mduduzi Paul Mokoena

    2016-03-01

    Full Text Available Diverse African traditional fermented foods and beverages, produced using different types of fermentation, have been used since antiquity because of their numerous nutritional values. Lactic acid bacteria (LAB isolated from these products have emerged as a welcome source of antimicrobials and therapeutics, and are accepted as probiotics. Probiotics are defined as live microbial food supplements which beneficially affect the host by improving the intestinal microbial balance. Currently, popular probiotics are derived from fermented milk products. However, with the growing number of consumers with lactose intolerance that are affected by dietary cholesterol from milk products, there is a growing global interest in probiotics from other food sources. The focus of this review is to provide an overview of recent developments on the applications of probiotic LAB globally, and to specifically highlight the suitability of African fermented foods and beverages as a viable source of novel probiotics.

  11. Production, properties, and industrial food application of lactic acid bacteria-derived exopolysaccharides.

    Zannini, Emanuele; Waters, Deborah M; Coffey, Aidan; Arendt, Elke K

    2016-02-01

    Exopolysaccharides (EPS)-producing lactic acid bacteria (LAB) are industrially important microorganisms in the development of functional food products and are used as starter cultures or coadjutants to develop fermented foods. There is large variability in EPS production by LAB in terms of chemical composition, quantity, molecular size, charge, presence of side chains, and rigidity of the molecules. The main body of the review will cover practical aspects concerning the structural diversity structure of EPS, and their concrete application in food industries is reported in details. To strengthen the food application and process feasibility of LAB EPS at industrial level, a future academic research should be combined with industrial input to understand the technical shortfalls that EPS can address. PMID:26621802

  12. Use of X-ray and gamma-induced mutants of lactic acid bacteria in the manufacture of dairy products

    With the aid of X-ray and gamma irradiation were got mutants of lactic acid bacteria, which steadily retain acquired properties. Use of proteolytically active mutant strains in the production of armianski and sovetski cheeses shortened the time of their ripening and increased their quality. Gamma-mutant strain L. lactis 1621/I-M with high phenolstability was received and antibiotic activity with respect to some representatives of pathogenic microflora of the bowels. Use of this mutant in starters for sour milk products will raise their therapeutic effect against intestinal diseases. Deep morphological changes are taking place in lactic acid bacteria under the influence of ionizing radiation. (orig.)

  13. Changes in oxidation-reduction potential during milk fermentation by wild lactic acid bacteria.

    Morandi, Stefano; Silvetti, Tiziana; Tamburini, Alberto; Brasca, Milena

    2016-08-01

    Oxidation-reduction potential (E h) is a fundamental physicochemical property of lactic acid bacteria that determines the microenvironment during the cheese manufacture and ripening. For this reason the E h is of growing interest in dairy research and the dairy industry. The objective of the study was to perform a comprehensive study on the reduction activity of wild lactic acid bacteria strains collected in different periods (from 1960 to 2012) from Italian dairy products. A total of 709 strains belonging to Lactococcus lactis, Enterococcus durans, E. faecium, E. faecalis and Streptococcus thermophilus species were studied for their reduction activity in milk. Kinetics of milk reduction were characterised by the minimum redox potential (E h7) and time of reaching E h7 (t min), the maximum difference between two measures (Δmax) and the time at which these maximum differences occurred (t*). Broad diversity in kinetic parameters was observed at both species and strain levels. E. faecalis and L. lactis resulted to be the most reducing species, while S. thermophilus was characterised by the lowest reducing power while the greatest heterogeneity was pointed out among E. durans and E. faecium strains. Considering the period of collection (1960-2012) we observed that the more recently isolated strains generally showed less reducing activity. This trend was particularly evident for the species E. durans, E. faecium and L. lactis while an opposite trend was observed in E. faecalis species. Data reported in this research provide new information for a deeper understanding of redox potential changes during milk fermentation due to bacterial growth. Gain knowledge of the redox potential of the LAB cultures could allow a better control and standardisation of cheesemaking process. PMID:27600976

  14. Toward Probiotict Food Product from Meat Through Isolation and Identification Lactic Acid Bacteria As Probiotic Culture Stater

    Yunilas Yunilas

    2014-01-01

    Full Text Available Probiotic food products of meat can provide extensive benefits, to increase the shelf life and nutritional value also improve the taste. The use of lactic acid bacteria culture (LAB derived from the isolation of the meat and the addition of probiotic cultures (Lactobacilli and Bifidobacteria in fermented sausage processing is expected to produce a probiotic sausage products with nutritional value, and better shelf life and improve health. This study aimed to isolate and identify lactic acid bacteria (LAB of meat as a starter culture fermented sausages. The parameters observed were gram test, catalase, motility, gas production, type of fermentation, growth at various temperatures and pH. The results were obtained 28 isolates, 17 isolates were able to produce acid and 8 of them are lactic acid bacteria (LAB with the characteristics of gram-positive, catalase negative, not motile, produces gas, are hetero and homo fermentative, optimum growth temperature of 300C and a few of them are able to grow on pH 3.5. Lactic acid bacteria that able to be combined with probiotics as sausage starter culture to the probiotic food products of meat.

  15. Application of electrochemical optical waveguide lightmode spectroscopy for studying the effect of different stress factors on lactic acid bacteria

    Electrochemical optical waveguide lightmode spectroscopy (EC-OWLS) has been developed to combine evanescent-field optical sensing with electrochemical control of surface adsorption processes. For bioanalytical sensing, a layer of indium tin oxide (ITO) served as both a high-refractive index waveguide and a conductive electrode. In addition, an electrochemical flow-through fluid cuvette was applied, which incorporated working, reference, and counter electrodes, and was compatible with the constraints of optical sensing. The subject of our study was to monitor how the different stress factors (lactic acid, acetic acid and hydrogen peroxide) influence the survival of lactic acid bacteria. The advantage of EC-OWLS technique is that we could carry out kinetic studies on the behaviour of bacteria under stress conditions, and after exposure of lactobacilli to acid and oxidative stress we get faster results about the status of bacteria compared to the traditional quantitative methods. After optimization of the polarization potential used, calibration curve was determined and the sensor response of different rate of living and damaged cells was studied. The bacterial cells were adsorbed in native form on the surface of the sensor by ensuring polarizing potential (1 V) and were exposed to different concentration of acetic acid and hydrogen peroxide solution to 1 h, respectively and the behaviour of bacteria was monitored. Results were compared to traditional micro-assay method

  16. Biohydrogenation of Linoleic Acid by Lactic Acid Bacteria for the Production of Functional Cultured Dairy Products: A Review

    Gabriela Christina Kuhl

    2016-02-01

    Full Text Available Conjugated linoleic acid (CLA isomers have attracted significant attention due to their important physiological properties, which have been observed in humans. Many lactic acid bacteria (LAB demonstrate the ability to produce CLA isomers (C18:2 cis-9, trans-11 and C18:2 trans-10, cis-12 from the linoleic acid (LA present in milk or in synthetic media. CLA isomers can be synthesized in vitro by LAB using vegetable oils rich in LA. The aim of this review is to present an update on the studies that have been conducted on the production of CLA isomers from LA mainly by LAB and of the factors that influence this conversion (source and concentration of LA and fermentation conditions. In addition, this review presents the relationship between the consumption of CLA isomers and their health benefits in humans such as anti-atherosclerosis and anti-carcinogenic effects. There is considerable variation between the studies concerning the beneficial effects of CLA in animal models, which have not been reflected in human studies. This can be attributed to the differences in the doses of CLA isomers used and to the different sources of CLA. Furthermore, the regulatory and scientific information classifying the physiological properties of CLA, which serve as support for the claims of its potential as a functional ingredient, are presented. More research is needed to determine whether CLA production by LAB can be enhanced and to determine the optimal requirements for these microbial cultures. Furthermore, safety and efficacy of CLA consumption have to be investigated in the future.

  17. Antimicrobial Efficacy of an Array of Essential Oils Against Lactic Acid Bacteria.

    Dunn, Laurel L; Davidson, P Michael; Critzer, Faith J

    2016-02-01

    The essential oils of clove bud, cinnamon bark and thyme, and their individual compounds including allyl isothiocyanate (AIT), carvacrol, cinnamaldehyde, cinnamic acid, eugenol, and thymol were initially assessed for antimicrobial activity against 9 lactic acid bacteria (LAB) species. Carvacrol and thymol were the most inhibitory with MICs of 0.1% (v/v and w/v, respectively). Cinnamaldehyde, cinnamon bark oil, clove bud oil, eugenol, and thyme oil were moderately inhibitive (MICs = 0.2% v/v), while cinnamic acid required a concentration of 0.5% (w/v). AIT was not effective with MICs in excess of concentrations tested (0.75% v/v). The bactericidal capability of the oil components carvacrol, cinnamaldehyde, eugenol, and thymol were further examined against Pediococcus acidilactici, Lactobacillus buchneri, and Leuconostoc citrovorum. Thymol at 0.1% (w/v) was bactericidal against L. citrovorum (>4-log reduction), but resulted in a 2-log CFU/mL reduction against L. buchneri and P. acidilactici. Cinnamaldehyde at 0.2% to 0.25% (v/v) was effective against L. citrovorum, L. buchneri, and P. acidilactici, resulting in a >2-log reduction. All 3 organisms were susceptible to 0.2% carvacrol with >3-log reduction observed after exposure for 6 h. Eugenol was the least effective. Concentrations of 0.2% and 0.25% (v/v) were needed to achieve an initial reduction in population, >3-log CFU/mL after 6 h exposure. However, at 0.2%, P. acidilactici and L. buchneri recovered to initial populations in 48 to 72 h. Results indicate essential oils have the capacity to inactivate LAB that are commonly associated with spoilage of shelf stable low-acid foods. PMID:26749216

  18. Lactic acid bacteria contribution to gut microbiota complexity: lights and shadows.

    Enrica ePessione

    2012-06-01

    Full Text Available Lactic Acid Bacteria (LAB are ancient organisms that cannot biosynthesize functional cytochromes, and cannot get ATP from respiration. Besides sugar fermentation, they evolved electrogenic decarboxylations and ATP-forming deiminations. The right balance between sugar fermentation and decarboxylation/deimination ensures buffered environments thus enabling LAB to survive in human gastric trait and colonize gut. A complex molecular cross-talk between LAB and host exists. LAB moonlight proteins are made in response to gut stimuli and promote bacterial adhesion to mucosa and stimulate immune cells. Similarly, when LAB are present, human enterocytes activate expression of specific genes only. Furthermore, LAB antagonistic relationships with other microorganisms constitutes the basis for their antiinfective role. Histamine and tyramine are LAB bioactive catabolites that act on the CNS, causing hypertension and allergies. Nevertheless, some LAB biosynthesize both GABA, that has relaxing effect on gut smooth muscles, and beta-phenylethylamine, that controls satiety and mood. Since LAB have reduced amino acid biosynthetic abilities, they developed a sophisticated proteolytic system, that is also involved in antihypertensive and opiod peptide generation from milk proteins.Short-chain fatty acids are glycolytic and phosphoketolase end-products, regulating epithelial cellproliferation and differentiation. Nevertheless, they constitute a supplementary energy source for the host, causing weight gain. Human metabolism can also be affected by anabolic LAB products such as conjugated linoleic acids (CLA. Some CLA isomers reduce cancer cell viability and ameliorate insulin resistance, while others lower the HDL/LDL ratio and modify eicosanoid production, with detrimental health effects.A further appreciated LAB feature is the ability to fix selenium into seleno-cysteine Thus opening interesting perspectives for their utilization as antioxidant nutraceutical

  19. Codominance of Lactobacillus plantarum and obligate heterofermentative lactic acid bacteria during sourdough fermentation.

    Ventimiglia, Giusi; Alfonzo, Antonio; Galluzzo, Paola; Corona, Onofrio; Francesca, Nicola; Caracappa, Santo; Moschetti, Giancarlo; Settanni, Luca

    2015-10-01

    Fifteen sourdoughs produced in western Sicily (southern Italy) were analysed by classical methods for their chemico-physical characteristics and the levels of lactic acid bacteria (LAB). pH and total titratable acidity (TTA) were mostly in the range commonly reported for similar products produced in Italy, but the fermentation quotient (FQ) of the majority of samples was above 4.0, due to the low concentration of acetic acid estimated by high performance liquid chromatography (HPLC). Specific counts of LAB showed levels higher than 10(8) CFU g(-1) for many samples. The colonies representing various morphologies were isolated and, after the differentiation based on phenotypic characteristics, divided into 10 groups. The most numerous group was composed of facultative heterofermentative isolates, indicating a relevance of this bacterial group during fermentation. The genetic analysis by randomly amplified polymorphic DNA (RAPD)-PCR, 16S rRNA gene sequencing and species-specific PCRs identified 33 strains as Lactobacillus plantarum, Lactobacillus curvatus and Lactobacillus graminis. Due to the consistent presence of L. plantarum, it was concluded that this species codominates with obligate heterofermentative LAB in sourdough production in this geographical area. In order to evaluate the performances at the basis of their fitness, the 29 L. plantarum strains were investigated for several technological traits. Twelve cultures showed good acidifying abilities in vitro and L. plantarum PON100148 produced the highest concentrations of organic acids. Eleven strains were positive for extracellular protease activity. Bacteriocin-like inhibitory substances (BLIS) production and antifungal activity was scored positive for several strains, included L. plantarum PON100148 which was selected as starter for experimental sourdough production. The characteristics of the sourdoughs and the resulting breads indicated that the best productions were obtained in presence of L

  20. Formation of Short-Chain Fatty Acids from H2 and CO2 by a Mixed Culture of Bacteria

    Goldberg, I.; Cooney, C L

    1981-01-01

    The biological utilization of CO2 and H2 for the formation of short-chain fatty acids was studied by using a mixed culture of bacteria. Optimization of a medium was carried out in continuous culture to identify limiting factors which controlled growth and production of organic acids. The optimal pH for growth and acid production was 7.0 at 37°C; the maximal cell concentration obtained was 5.9 g of cells per liter (dry weight), and the maximal amount of volatile acids formed was 4.7 g/liter, w...

  1.  Mycolic acids – potential biomarkers of opportunistic infections caused by bacteria of the suborder Corynebacterineae

    Konrad Kowalski

    2012-06-01

    Full Text Available  Mycolic acids are one of the basic elements of the cell wall structure of bacteria belonging to the suborder Corynebacterineae, constituting from 20�0to 40�0of dry weight. Additionally, they show high structural diversity within each family and species. Nowadays, profiles of mycolic acids are widely described for the genus Mycobacterium, the causative agent of tuberculosis. However, the suborder Corynebacterineae also includes many representatives of opportunistic human pathogens, e.g. Dietzia, Gordonia, Nocardia and Rhodococcus. Currently, an increased infection risk caused by this group of microorganisms especially in immunocompromised patients has been observed. Better knowledge of mycolic acid profiles for Corynebacterineae may allow identification of mycolic acids as diagnostic markers in the detection of opportunistic bacterial infections. Modern techniques of chemical analysis, including mass spectrometry, may enable the development of new chemotaxonomic methods for the detection and differentiation of bacteria within the suborder Corynebacterineae.

  2. Revisiting normal {sup 51}Cr-ethylenediaminetetraacetic acid clearance values in children

    Piepsz, A.; Tondeur, M. [Department of Radioisotopes, CHU St Pierre, Brussels (Belgium); Ham, H. [Department of Nuclear Medicine, UZ Ghent, Ghent (Belgium)

    2006-12-15

    Normal {sup 51}Cr-ethylenediaminetetraacetic acid (EDTA) clearance values as a function of age were published a number of years ago. These values were based on data from children with a normal left to right ratio and a normal appearance on DMSA scintigraphy, despite the presence of an acute renal infection. At that time, the authors were unaware that hyperfiltration is a common phenomenon in patients with acute renal infection and that their normal values could have been significantly overestimated. The present work therefore aimed to re-appraise these normal values. In a first step, in order to verify the previous results, the same type of population was selected, namely patients with present or past urinary tract infection but normal images and a normal left to right ratio on DMSA scintigraphy. In a second step, the selection was based on patients who had had no recent urinary tract infection. In both series, a single blood sample method was used for the evaluation of {sup 51}Cr-EDTA clearance. In the first group of patients, the results obtained were almost identical to those previously published. In the second group of patients, the results were significantly lower: after 2 years of age, the mean GFR value was 104 ml/min/1.73 m{sup 2} (10th and 90th percentiles 81 and 135 ml/min/1.73 m{sup 2}, respectively), compared with 117 ml/min/1.73 m{sup 2} in the first group. The data of the second group are probably more representative of the true normal GFR values and can be applied to the entire paediatric population. (orig.)

  3. Fed-batch Fermentation of Lactic Acid Bacteria to Improve Biomass Production: A Theoretical Approach

    Beng Lee, Boon; Tham, Heng Jin; Chan, Eng Seng

    Recently, fed-batch fermentation has been introduced in an increasing number of fermentation processes. Previous researches showed that fed-batch fermentation can increase the biomass yield of many strains. Improvement of the biomass yield is interested because biomass from lactic acid bacteria (LAB) fermentation is widely used in food and pharmaceutical industry. The aim of this research is to study the ability and feasibility of fed-batch fermentation to improve biomass production of LAB. Appropriate model has been selected from literature. Monod equation described the substrate limitation of LAB and the product inhibition of LAB follows a non-competitive model. Furthermore, the lactic acid production follows Luedeking and Piret model. Then the models are applied to simulate the fermentation of batch and fed-batch cultures by using MATLAB. From the results of simulation, fed-batch fermentation showed that substrate limitation and substrate inhibition can be avoided. Besides that, the variable volume fed-batch fermentation also showed that product inhibition can be eliminated by diluting the product concentration with added fresh feed. However, it was found that fed-batch fermentation is not economically feasible because large amount of substrate is required to reduce the product inhibition effect. Therefore, fed-batch fermentation plays more importance role if the fermentation strain has high Ks value or low Kp value.

  4. Effects of lactic acid bacteria isolated from fermented mustard on lowering cholesterol

    Shu; Chen; Wang; Chen; Kai; Chang; Shu; Chang; Chan; Jiunn; Shiuh; Shieh; Chih; Kwang; Chiu; Pin-Der; Duh

    2014-01-01

    Objective:To evaluate the ability of lactic acid bacteria(LAB)strains isolated from fermented mustard to lower the cholesterol in vitro.Methods:The ability of 50 LAB strains isolated from fermented mustard on lowering cholesterol in vitro was determined by modified o-phtshalaldehyde method.The LAB isolates were analyzed for their resistance to acid and bile salt.Strains with lowering cholesterol activity,were determined adherence to Caco-2 cells.Results:Strain B0007,B0006 and B0022 assimilated more cholesterol than BCRC10474 and BCRC17010.The isolated strains showed tolerance to pH 3.0 for 3h despite variations in the degree of viability and bile-tolerant strains,with more than 10~s CFU/mL after incubation for 24 h at 1%oxigall in MRS.In addition,strain B0007 and B0022 identified as Lactobacillus plantarum with 16S rDNA sequences were able to adhere to the Caco-2 cell lines.Conclusions:These strains B0007 and B0022 may be potential functional sources for cholesterollowering activities as well as adhering to Caco-2 cell lines.

  5. Isolation and Selection of Anti-Candida albicans Metabolites Producing Lactic Acid Bacteria from Various Sources

    Tanes SUNGSRI

    2015-02-01

    Full Text Available Five hundred and fifty-two of lactic acid bacteria (LAB have been isolated and screened from fermented foods, natural sources and dairy effluents on De Mann Rogosa Sharpe (MRS agar. Fifty-one isolates, in the percentile of 9.24, produced the secondary metabolites that could inhibit the growth of Candida albicans BCC6120 by using dual culture overlay assay. The culture broth of LAB, moreover, showed anti-C. albicans activity in acidic condition at pH range of 3.0-5.0 by using agar well diffusion method. Interestingly, the isolate L-47-2 showed much more colonization surrounding the surface of sterile toothpick and test tube when growing in MRS broth. The identification of isolate L-47-2 by morphological and biochemical characteristics using API 50 CHL Test Kit and further confirmed by 16S rRNA gene sequence analysis revealed that isolate L47-2 was similar to Lactobacillus paracasei with 99% nucleotide identity.    

  6. Isolation and characteristics of lactic acid bacteria isolated from ripe mulberries in Taiwan

    Yi-sheng Chen

    2010-12-01

    Full Text Available The objective of this study was to isolate, characterize, and identify lactic acid bacteria (LAB from ripe mulberries collected in Taiwan. Ripe mulberry samples were collected at five mulberry farms, located in different counties of Taiwan. Eighty-eight acid-producing cultures were isolated from these samples, and isolates were divided into classes first by phenotype, then into groups by restriction fragment length polymorphism (RFLP analysis and sequencing of 16S ribosomal DNA (rDNA. Phenotypic and biochemical characteristics led to identification of four bacterial groups (A to D. Weissella cibaria was the most abundant type of LAB distributed in four mulberry farms, and Lactobacillus plantarum was the most abundant LAB found in the remaining farm. Ten W. cibaria and one Lactococcus lactis subsp. lactis isolate produced bacteriocins against the indicator strain Lactobacillus sakei JCM 1157T. These results suggest that various LAB are distributed in ripe mulberries and W. cibaria was the most abundant LAB found in this study.

  7. Probiotic potential of selected lactic acid bacteria strains isolated from Brazilian kefir grains.

    Leite, A M O; Miguel, M A L; Peixoto, R S; Ruas-Madiedo, P; Paschoalin, V M F; Mayo, B; Delgado, S

    2015-06-01

    A total of 34 lactic acid bacteria isolates from 4 different Brazilian kefir grains were identified and characterized among a group of 150 isolates, using the ability to tolerate acidic pH and resistance to bile salts as restrictive criteria for probiotic potential. All isolates were identified by amplified ribosomal DNA restriction analysis and 16S rDNA sequencing of representative amplicons. Eighteen isolates belonged to the species Leuconostoc mesenteroides, 11 to Lactococcus lactis (of which 8 belonged to subspecies cremoris and 3 to subspecies lactis), and 5 to Lactobacillus paracasei. To exclude replicates, a molecular typing analysis was performed by combining repetitive extragenic palindromic-PCR and random amplification of polymorphic DNA techniques. Considering a threshold of 90% similarity, 32 different strains were considered. All strains showed some antagonistic activity against 4 model food pathogens. In addition, 3 Lc. lactis strains and 1 Lb. paracasei produced bacteriocin-like inhibitory substances against at least 2 indicator organisms. Moreover, 1 Lc. lactis and 2 Lb. paracasei presented good total antioxidative activity. None of these strains showed undesirable enzymatic or hemolytic activities, while proving susceptible or intrinsically resistant to a series of clinically relevant antibiotics. The Lb. paracasei strain MRS59 showed a level of adhesion to human Caco-2 epithelial cells comparable with that observed for Lactobacillus rhamnosus GG. Taken together, these properties allow the MRS59 strain to be considered a promising probiotic candidate. PMID:25841972

  8. SCREENING OF LACTIC ACID BACTERIA FROM SUDANESE FERMENTED FOODS FOR BACTERIOCIN PRODUCTION

    Yasmeen Y. A. Elyas

    2015-04-01

    Full Text Available Forty isolates of lactic acid bacteria (LAB were isolated from different types of fermented foods consumed in Sudan. Phenotypic tests revealed that all isolates were homofermentative LAB. Twenty-four isolates produced inhibitory substances primarily active against Staphylococcus aureus ATCC 2818 and Escherichia coli ATCC 29522. The inhibitory activity of 88% of enterococci and 58% of lactobacilli was recorded from meat isolates, whereas all activity of pediococcal isolates came from fermented milk isolates. The cell-free cultures of 18 isolates exhibiting inhibitory activity was chosen for further investigation such as sensitivity to proteolytic enzyme (pepsin, effect of heat treatment (60°C for 60min, 100°C for 20min and 121°C for 15min and effect of pH ( pH 2.0, pH 6.5, and pH 9.0. The inhibitory activity was eliminated upon treatment with pepsin. The bacteriocin-like substances lost their activity after heating at all temperatures used and at alkaline pH (9.0, whereas they were active at acidic pH (2.0. The antimicrobial activity of bacteriocin-like substances produced by the isolated LAB could prevent spoilage and/or pathogenic microorganism in Sudanese fermented food. Further study should be related with species identification of the producer strains and with the purification and characterization of these becteriocin-like substances in order to explore them in food industry.

  9. Antioxidant Activity of Peptides from Fermented Milk with Mix Culture of Lactic Acid Bacteria and Yeast

    Yun Li

    2015-02-01

    Full Text Available The aim of the present study is to investigate the production of antioxidant peptides during milk fermentation with co-culture of Lactic Acid Bacteria (LAB and yeast. Five LAB strains, previously screened with higher hydrolysis activity and Debaryomyces hansenii H2 which isolated from Tibet kefir were used in the study. The peptides separated from fermented milk were analysed antioxidant activity with DPPH radical scavenging, hydroxyl radical scavenging, chelation of metal ions and reducing power assays. The growth of Streptococcus. thermophilus Lactobacillus. delbrueckii ssp. bulgaricus and Lactococcus. lactis was enhanced with co-cultures and L. acidophilus was inhibited in co-culture with yeast. In co-culture with yeast, a significant decrease of the acidity was observed among all the fermentation and the pH reached higher values than in single LAB cultures. Except for L.delbrueckii ssp. bulgaricus, there was no significant difference of protein hydrolysis with other test LAB strains between co-culture and single culture. The co-incubation of LAB with the yeast developed a stronger antioxidant activity in DPPH radical and hydroxyl radical scavenging and no significant (p>0.05 difference in chelation of metal ions. The reducing power of L.delbrueckii ssp. bulgaricus and L. helveticus in co-culture was significant higher than those of single culture.

  10. Source Tracking and Succession of Kimchi Lactic Acid Bacteria during Fermentation.

    Lee, Se Hee; Jung, Ji Young; Jeon, Che Ok

    2015-08-01

    This study aimed at evaluating raw materials as potential lactic acid bacteria (LAB) sources for kimchi fermentation and investigating LAB successions during fermentation. The bacterial abundances and communities of five different sets of raw materials were investigated using plate-counting and pyrosequencing. LAB were found to be highly abundant in all garlic samples, suggesting that garlic may be a major LAB source for kimchi fermentation. LAB were observed in three and two out of five ginger and leek samples, respectively, indicating that they can also be potential important LAB sources. LAB were identified in only one cabbage sample with low abundance, suggesting that cabbage may not be an important LAB source. Bacterial successions during fermentation in the five kimchi samples were investigated by community analysis using pyrosequencing. LAB communities in initial kimchi were similar to the combined LAB communities of individual raw materials, suggesting that kimchi LAB were derived from their raw materials. LAB community analyses showed that species in the genera Leuconostoc, Lactobacillus, and Weissella were key players in kimchi fermentation, but their successions during fermentation varied with the species, indicating that members of the key genera may have different acid tolerance or growth competitiveness depending on their respective species. PMID:26133985

  11. Binding and detoxification of chlorpyrifos by lactic acid bacteria on rice straw silage fermentation.

    Wang, Yan-Su; Wu, Tian-Hao; Yang, Yao; Zhu, Cen-Ling; Ding, Cheng-Long; Dai, Chuan-Chao

    2016-01-01

    This investigation examined the reduction of pesticide residues on straw inoculated with lactic acid bacteria (LAB) during ensiling. Lactobacillus casei WYS3 was isolated from rice straw that contained pesticide residues. Non-sterilized rice straw, which was inoculated with L. casei WYS3, showed increased removal of chlorpyrifos after ensiling, compared with rice straw that was not inoculated with L. casei WYS3 or sterilized rice straw. In pure culture, these strains can bind chlorpyrifos as indicated by high-performance liquid chromatography analysis. Viable L. casei WYS3 was shown to bind 33.3-42% of exogenously added chlorpyrifos. These results are similar to those of acid-treated cells but less than those of heat-treated cells, which were found to bind 32.0% and 77.2% of the added chlorpyrifos respectively. Furthermore, gas chromatography-mass spectrometry analysis determined that L. casei WYS3 detoxified chlorpyrifos via P-O-C cleavage. Real-time polymerized chain reaction analysis determined that organophosphorus hydrolase gene expression tripled after the addition of chlorpyrifos to LAB cultures, compared with the control group (without chlorpyrifos). This paper highlights the potential use of LAB starter cultures for the detoxification and removal of chlorpyrifos residues in the environment. PMID:26852781

  12. Effects of lactic acid bacteria isolated from fermented mustard on lowering cholesterol

    Shu Chen Wang; Chen Kai Chang; Shu Chang Chan; Jiunn Shiuh Shieh; Chih Kwang Chiu; Pin-Der Duh

    2014-01-01

    Objective: To evaluate the ability of lactic acid bacteria (LAB) strains isolated from fermented mustard to lower the cholesterol in vitro.Methods:The ability of 50 LAB strains isolated from fermented mustard on lowering cholesterol in vitro was determined by modified o-phtshalaldehyde method. The LAB isolates were analyzed for their resistance to acid and bile salt. Strains with lowering cholesterol activity, were determined adherence to Caco-2 cells. Results: Strain B0007, B0006 and B0022 assimilated more cholesterol than BCRC10474 and BCRC 17010. The isolated strains showed tolerance to pH 3.0 for 3 h despite variations in the degree of viability and bile-tolerant strains, with more than 108 CFU/mL after incubation for 24 h at 1%oxigall in MRS. In addition, strain B0007 and B0022 identified as Lactobacillus plantarum with 16S rDNA sequences were able to adhere to the Caco-2 cell lines.Conclusions:These strains B0007 and B0022 may be potential functional sources for cholesterol-lowering activities as well as adhering to Caco-2 cell lines.

  13. Amoxicillin-clavulanic acid in treatment of urinary tract infection due to gram-negative bacteria resistant to penicillin.

    Martinelli, R; A.A. Lopes; Oliveira, M.M.; Rocha, H

    1981-01-01

    Twenty-two adult patients with urinary tract infections caused by penicillin-resistant bacteria completed treatment with amoxicillin alone or amoxicillin plus clavulanic acid in a randomized double-blind clinical trial. Of the 13 patients treated with amoxicillin plus clavulanic acid, the absence of bacteriuria within 7 days of therapy was observed in 85%, as compared with only 25% of the 8 patients receiving amoxicillin only. There were no significant side effects nor any clinical, biochemic...

  14. Production of fermented probiotic beverages from milk permeate enriched with whey retentate and identification of present lactic acid bacteria

    Jagoda Šušković; Slavko Kirin; Stjepan Mahnet; Jadranka Frece; Jasna Beganović; Josip Turk; Andreja Leboš Pavunc

    2009-01-01

    In this research the application of bacterial strains Lactobacillus acidophilus M92, Lactobacillus plantarum L4 and Enterococcus faecium L3 in the production of fermented probiotic beverages from milk permeate enriched with 10 % (v/v) whey retentate, was investigated. In the previous researches of probiotic concept, probiotic properties of these three strains of lactic acid bacteria have been defined. At the end of controlled fermentation, probiotic strains have produced 7.4 g/L lactic acid, ...

  15. Toward Probiotict Food Product from Meat Through Isolation and Identification Lactic Acid Bacteria As Probiotic Culture Stater

    Yunilas Yunilas; Lili Warly; Edi Mirwandhono

    2014-01-01

    Probiotic food products of meat can provide extensive benefits, to increase the shelf life and nutritional value also improve the taste. The use of lactic acid bacteria culture (LAB) derived from the isolation of the meat and the addition of probiotic cultures (Lactobacilli and Bifidobacteria) in fermented sausage processing is expected to produce a probiotic sausage products with nutritional value, and better shelf life and improve health. This study aimed to isolate and identify lactic acid...

  16. Fermentation quality and nutritive value of rice crop residue based silage ensiled with addition of epiphytic lactic acid bacteria

    2011-01-01

    Silage is the feedstuff resulted from the preservation of forages through lactic acid fermentation. The aim of this study was to evaluate nutritive value, fermentation characteristics and nutrients digestibility of rice crop residue based silage ensiled with epiphytic lactic acid bacteria (LAB). The mixture of rice crop residue (RC), soybean curd residue (SC) and cassava waste (CW) in a 90: 5: 5 (on dry matter basis) ratio was used as silage material. Three treatments silage were (A) RC + SC...

  17. Lactic acid bacteria and yeasts associated with gowé production from sorghum in Bénin

    Vieira-Dalodé, G.; Jespersen, Lene; Hounhouigan, J.;

    2007-01-01

    different fermentation times. DNA amplification by internal transcribed spacer-polymerase chain reaction of 288 lactic acid bacteria (LAB) isolates and 16S rRNA gene sequencing of selected strains revealed that the dominant LAB responsible for gowé fermentation were Lactobacillus fermentum, Weissella...

  18. Lactic acid bacteria: inhibition of angiotensin converting enzyme in vitro and in vivo

    Fuglsang, Anders; Rattray, Fergal; Nilsson, Dan;

    2003-01-01

    A total of 26 strains of wild-type lactic acid bacteria, mainly belonging to Lactococcus lactis and Lactobacillus helveticus , were assayed in vitro for their ability to produce a milk fermentate with inhibitory activity towards angiotensin converting enzyme (ACE). It was clear that the test...

  19. 乳酸菌益生功能研究进展%Advances in Probiotic Properties of Lactic Acid Bacteria

    林谦

    2015-01-01

    介绍了益生菌的概念、乳酸菌的益生功能,并指出了乳酸菌益生功能研究中的问题。%The concept of probiotc, probiotic properties of lactic acid bacteria and challenges of development were reviewed.

  20. Screening of lactic acid bacteria from Indonesia reveals glucansucrase and fructansucrase genes in two different Weissella confusa strains from soya

    Malik, Amarila; Radji, Maksum; Kralj, Slavko; Dijkhuizen, Lubbert

    2009-01-01

    Homopolysaccharide (glucan and fructan) synthesis from sucrose by sucrase enzymes in lactic acid bacteria (LAB) has been well studied in the genera Leuconostoc, Streptococcus and Lactobacillus. This study aimed to identify and characterize genes encoding glucansucrase/glucosyltransferase (GTF) and f

  1. Characterization of prominent nitrate-reducing and amino acid-utilizing bacteria from nitrotoxin-enriched equine cecal populations

    In the present study, populations of equine cecal microbes enriched for enhanced rates of 3-nitro-1-propionic acid (NPA) or nitrate metabolism were diluted and cultured for NPA-metabolizing bacteria on a basal enrichment medium (BEM) or tryptose soy agar (TSA) medium supplemented with either 5 mM NP...

  2. Biofilm-associated indole acetic acid producing bacteria and their impact in the proliferation of biofilm mats in solar salterns

    Kerkar, S.; Raiker, L.; Tiwari, A.; Mayilraj, S.; Dastager, S.

    viz. Nerul and Curca to find a possible reason for the rapid proliferation of these solar biofilms. Out of the 125 bacteria isolated from these biofilms, 16 produced indole-3-acetic acid (IAA). Rapid in-situ assay with Salkowski reagent and HPLC...

  3. Role of phosphate in the central metabolism of two lactic acid bacteria-a comparative systems biology approach

    Levering, J.; Musters, M.W.J.M.; Bekker, M.; Bellomo, D.; Fiedler, T.; Vos, de W.M.; Hugenholtz, F.; Kreikemeyer, B.; Kummer, U.; Teusink, B.

    2012-01-01

    Lactic acid-producing bacteria survive in distinct environments, but show common metabolic characteristics. Here we studied the dynamic interactions of the central metabolism in Lactococcus lactis, extensively used as a starter culture in the dairy industry, and Streptococcus pyogenes, a human patho

  4. Role of phosphate in the central metabolism of two lactic acid bacteria - a comparative systems biology approach.

    J. Levering; M.W. Musters; M. Bekker; D. Bellomo; T. Fiedler; W.M. de Vos; J. Hugenholtz; B. Kreikemeyer; U. Kummer; B. Teusink

    2012-01-01

    Lactic acid-producing bacteria survive in distinct environments, but show common metabolic characteristics. Here we studied the dynamic interactions of the central metabolism in Lactococcus lactis, extensively used as a starter culture in the dairy industry, and Streptococcus pyogenes, a human patho

  5. Phylogenetic group- and species-specific oligonucleotide probes for single-cell detection of lactic acid bacteria in oral biofilms

    Quevedo, Beatrice; Giertsen, Elin; Zijnge, Vincent; Luethi-Schaller, Helga; Guggenheim, Bernhard; Thurnheer, Thomas; Gmuer, Rudolf

    2011-01-01

    Background: The purpose of this study was to design and evaluate fluorescent in situ hybridization (FISH) probes for the single-cell detection and enumeration of lactic acid bacteria, in particular organisms belonging to the major phylogenetic groups and species of oral lactobacilli and to Abiotroph

  6. Mannitol production by lactic acid bacteria grown in supplemented carob syrup.

    Carvalheiro, Florbela; Moniz, Patrícia; Duarte, Luís C; Esteves, M Paula; Gírio, Francisco M

    2011-01-01

    Detailed kinetic and physiological characterisation of eight mannitol-producing lactic acid bacteria, Leuconostoc citreum ATCC 49370, L. mesenteroides subsp. cremoris ATCC19254, L. mesenteroides subsp. dextranicum ATCC 19255, L. ficulneum NRRL B-23447, L. fructosum NRRL B-2041, L. lactis ATCC 19256, Lactobacillus intermedius NRRL 3692 and Lb. reuteri DSM 20016, was performed using a carob-based culture medium, to evaluate their different metabolic capabilities. Cultures were thoroughly followed for 30 h to evaluate consumption of sugars, as well as production of biomass and metabolites. All strains produced mannitol at high yields (>0.70 g mannitol/g fructose) and volumetric productivities (>1.31 g/l h), and consumed fructose and glucose simultaneously, but fructose assimilation rate was always higher. The results obtained enable the studied strains to be divided mainly into two groups: one for which glucose assimilation rates were below 0.78 g/l h (strains ATCC 49370, ATCC 19256 and ATCC 19254) and the other for which they ranged between 1.41 and 1.89 g/l h (strains NRRL B-3692, NRRL B-2041, NRRL B-23447 and DSM 20016). These groups also exhibited different mannitol production rates and yields, being higher for the strains with faster glucose assimilation. Besides mannitol, all strains also produced lactic acid and acetic acid. The best performance was obtained for L. fructosum NRRL B-2041, with maximum volumetric productivity of 2.36 g/l h and the highest yield, stoichiometric conversion of fructose to mannitol. PMID:20820868

  7. Identification and Antimicrobial Activity Detection of Lactic Acid Bacteria Isolated from Corn Stover Silage

    Li, Dongxia; Ni, Kuikui; Pang, Huili; Wang, Yanping; Cai, Yimin; Jin, Qingsheng

    2015-01-01

    A total of 59 lactic acid bacteria (LAB) strains were isolated from corn stover silage. According to phenotypic and chemotaxonomic characteristics, 16S ribosomal DNA (rDNA) sequences and recA gene polymerase chain reaction amplification, these LAB isolates were identified as five species: Lactobacillus (L.) plantarum subsp. plantarum, Pediococcus pentosaceus, Enterococcus mundtii, Weissella cibaria and Leuconostoc pseudomesenteroides, respectively. Those strains were also screened for antimicrobial activity using a dual-culture agar plate assay. Based on excluding the effects of organic acids and hydrogen peroxide, two L. plantarum subsp. plantarum strains ZZU 203 and 204, which strongly inhibited Salmonella enterica ATCC 43971T, Micrococcus luteus ATCC 4698T and Escherichia coli ATCC 11775T were selected for further research on sensitivity of the antimicrobial substance to heat, pH and protease. Cell-free culture supernatants of the two strains exhibited strong heat stability (60 min at 100°C), but the antimicrobial activity was eliminated after treatment at 121°C for 15 min. The antimicrobial substance remained active under acidic condition (pH 2.0 to 6.0), but became inactive under neutral and alkaline condition (pH 7.0 to 9.0). In addition, the antimicrobial activities of these two strains decreased remarkably after digestion by protease K. These results preliminarily suggest that the desirable antimicrobial activity of strains ZZU 203 and 204 is the result of the production of a bacteriocin-like substance, and these two strains with antimicrobial activity could be used as silage additives to inhibit proliferation of unwanted microorganism during ensiling and preserve nutrients of silage. The nature of the antimicrobial substances is being investigated in our laboratory. PMID:25924957

  8. Characterization, Identification and Application of Lactic Acid Bacteria Isolated from Forage Paddy Rice Silage

    Ni, Kuikui; Wang, Yanping; Li, Dongxia; Cai, Yimin; Pang, Huili

    2015-01-01

    There has been growing interest to develop forage rice as a new feed resource for livestock. This study was to characterize the natural population of lactic acid bacteria (LAB) and select potentially excellent strains for paddy rice silage preparation in China. One hundred and twenty-six strains were isolated and screened from paddy rice silage prepared using a small-scale fermentation system, and ninety-nine of these isolates were considered to be LAB based on their Gram-positive and catalase-negative morphology and the production of most of their metabolic products as lactic acid. These isolates were divided into eight groups (A-H) on the basis of their morphological and biochemical characteristics. The Group A to H strains were identified as Lactobacillus (L.) plantarum subsp. plantarum (species ratio: 8.1%), L. casei (5.1%), Leuconostoc (Ln.) pseudomesenteroides (11.1%), Pediococcus (P.) pentosaceus (24.2%), Enterococcus (E.) mundtii (12.1%), Lactococcus (Lc.) garvieae (15.2%), E. faecium (9.1%) and Lc. lactis subsp. lactis (15.2%) based on sequence analyses of their 16S rRNA and recA genes. P. pentosaceus was the most abundant member of the LAB population in the paddy rice silage. A selected strain, namely L. casei R 465, was found to be able to grow under low pH conditions and to improve the silage quality with low pH and a relatively high content of lactic acid. This study demonstrated that forage paddy rice silage contains abundant LAB species and its silage can be well preserved by inoculation with LAB, and that strain R 465 can be a potentially excellent inoculant for paddy rice silage. PMID:25803578

  9. Gassericin A: a circular bacteriocin produced by lactic acid bacteria Lactobacillus gasseri.

    Pandey, Neha; Malik, R K; Kaushik, J K; Singroha, Garima

    2013-11-01

    During the recent years extensive efforts have been made to find out bacteriocins from lactic acid bacteria (LAB) active against various food spoilage and pathogenic bacteria, and superior stabilities against heat treatments and pH variations. Bacteriocins isolated from LAB have been grouped into four classes. Circular bacteriocins which were earlier grouped among the four groups of bacteriocins, have recently been proposed to be classified into a different class, making it class V bacteriocins. Circular bacteriocins are special molecules, whose precursors must be post translationally modified to join the N to C termini with a head-to-tail peptide bond. Cyclization appears to make them less susceptible to proteolytic cleavage, high temperature and pH, and, therefore, provides enhanced stability as compared to linear bacteriocins. The advantages of circularization are also reflected by the fact that a significant number of macrocyclic natural products have found pharmaceutical applications. Circular bacteriocins were unknown two decades ago, and even to date, only a few circular bacteriocins from a diverse group of Gram positive organisms have been reported. The first example of a circular bacteriocin was enterocin AS-48, produced by Enterococcus faecalis AS-48. Gassereccin A, produced by Lactobacillus gasseri LA39, Reutericin 6 produced by Lactobacillus reuteri LA6 and Circularin A, produced by Clostridium beijerinickii ATCC 25,752, are further examples of this group of antimicrobial peptides. In the present scenario, Gassericin A can be an important tool in the food preservation owing to its properties of high pH and temperature tolerance and the fact that it is produced by LAB L. gasseri, whose many strains are proven probiotic. PMID:23712477

  10. Comparative genomics of lactic acid bacteria reveals a niche-specific gene set

    Callanan Michael

    2009-03-01

    Full Text Available Abstract Background The recently sequenced genome of Lactobacillus helveticus DPC4571 1 revealed a dairy organism with significant homology (75% of genes are homologous to a probiotic bacteria Lb. acidophilus NCFM 2. This led us to hypothesise that a group of genes could be determined which could define an organism's niche. Results Taking 11 fully sequenced lactic acid bacteria (LAB as our target, (3 dairy LAB, 5 gut LAB and 3 multi-niche LAB, we demonstrated that the presence or absence of certain genes involved in sugar metabolism, the proteolytic system, and restriction modification enzymes were pivotal in suggesting the niche of a strain. We identified 9 niche specific genes, of which 6 are dairy specific and 3 are gut specific. The dairy specific genes identified in Lactobacillus helveticus DPC4571 were lhv_1161 and lhv_1171, encoding components of the proteolytic system, lhv_1031 lhv_1152, lhv_1978 and lhv_0028 encoding restriction endonuclease genes, while bile salt hydrolase genes lba_0892 and lba_1078, and the sugar metabolism gene lba_1689 from Lb. acidophilus NCFM were identified as gut specific genes. Conclusion Comparative analysis revealed that if an organism had homologs to the dairy specific geneset, it probably came from a dairy environment, whilst if it had homologs to gut specific genes, it was highly likely to be of intestinal origin. We propose that this "barcode" of 9 genes will be a useful initial guide to researchers in the LAB field to indicate an organism's ability to occupy a specific niche.

  11. Selection of oleuropein-degrading lactic acid bacteria strains isolated from fermenting Moroccan green olives

    Ghabbour, N.

    2011-03-01

    Full Text Available A total of 177 strains of lactic acid bacteria (LAB were isolated from early-stage Moroccan Picholine green olive fermentation, including Lactobacillus plantarum (44.63%, Lactobacillus pentosus (25.99%, Lactobacillus brevis (9.61% and Pediococcus pentosaceus (19.77%. All the isolates were screened for their tolerance to olive leaf extract and oleuropein. Most of the isolates (85.3% were found able to degrade oleuropein, when evaluated by either oleuropein or 5-Bromo- 4-chloro-3-indolyl β-D-glucuronide (X-Gluc as substrates. The biodegradation capacity of the selected strains of each species was confirmed by HPLC analysis.

    Un total de 177 cepas de bacterias ácido lácticas (LAB fueron aisladas en las primeras etapas de la fermentación de aceitunas verdes marroquíes Picholine, incluyendo Lactobacillus plantarum (44.63%, Lactobacillus pentosus (25.99%, Lactobacillus brevis (9.61% y Pediococcus pentosaceus (19.77%. Todos los aislados fueron evaluados mediante su tolerancia a extractos de hojas de olivo y oleuropeína. La mayoría de los aislados (85,3% degradaron oleuropeína, cuando fueron evaluados usando oleuropeína o 5-Bromo-4-cloro- 3-indolil β-D-glucuronido (X-Gluc como sustrato. La capacidad de biodegradación de las cepas seleccionadas para cada especie fue confirmada mediante análisis por HPLC.

  12. Autoinducer-2 properties of kimchi are associated with lactic acid bacteria involved in its fermentation.

    Park, Hyunjoon; Shin, Heuynkil; Lee, Kyuyeon; Holzapfel, Wilhelm

    2016-05-16

    Bacteria use the cell density-dependent quorum signalling system to regulate particular gene expressions. In food microbiology, signalling is well known for its relation to (foodborne) pathogenicity, food spoilage, and biofilm formation. Quorum quenching and inhibition are thus being considered as a feasible approach in food preservation and safety. In the case of the luxS-mediated universal quorum sensing using autoinducer-2 (AI-2), however, it could be a different issue. Several studies have reported a luxS AI-2 synthase homologue in numerous bacteria, comprising both pathogens and beneficial strains. A recent study has shown the AI-2 signal to restore the balance of the major phyla of the gut microbiota in antibiotic-induced dysbiosis. We measured the AI-2 activity of the lactic fermented food, kimchi, and found different AI-2 signalling intensities. In order to trace the origin of the signal production, we obtained 229 lactic acid bacterial isolates from the kimchi samples, and detected the AI-2 properties of each isolate using a modified AI-2 bioluminescence assay. Our results showed isolates of dominant species of the genera Lactobacillus, Weissella and Leuconostoc which either produced or inhibited the AI-2 signal. No isolate of the dominant species Lactobacillus sakei (75 isolates) and Lactobacillus curvatus (28 isolates) showed AI-2 producing activity, while AI-2 inhibition could not be detected for any of the 31 Lactobacillus plantarum isolates. These results suggest the AI-2 activity of kimchi to result from the interaction of the associated microbial food cultures (MFCs) during fermentation. Thus far, only sparse information is available on AI-2 signalling interaction in fermented food, however, we suggest that fermented food may be a supplier of AI-2 signalling molecules via typical MFCs. PMID:26977818

  13. Bacteriocins from lactic acid bacteria: purification, properties and use as biopreservatives

    José Luis Parada

    2007-05-01

    Full Text Available Biopreservation systems in foods are of increasing interest for industry and consumers. Bacteriocinogenic lactic acid bacteria and/or their isolated bacteriocins are considered safe additives (GRAS, useful to control the frequent development of pathogens and spoiling microorganisms in foods and feed. The spreading of bacterial antibiotic resistance and the demand for products with fewer chemicals create the necessity of exploring new alternatives, in order to reduce the abusive use of therapeutic antibiotics. In this context, bacteriocins are indicated to prevent the growth of undesirable bacteria in a food-grade and more natural way, which is convenient for health and accepted by the community. According to their properties, structure, molecular weight (MW, and antimicrobial spectrum, bacteriocins are classified in three different groups: lantibiotics and non-lantibiotics of low MW, and those of higher MW. Several strategies for isolation and purification of bacteriocins from complex cultivation broths to final products were described. Biotechnological procedures including salting-out, solvent extraction, ultrafiltration, adsorption-desortion, ion-exchange, and size exclusion chromatography are among the most usual methods. Peptide structure-function studies of bacteriocins and bacterial genetic advances will help to understand the molecular basis of their specificity and mode of action. Nisin is a good example of commercial success, and a good perspective is open to continue the study and development of new bacteriocins and their biotechnological applications. These substances in appropriate concentrations may be used in veterinary medicine and as animal growth promoter instead usual antibiotics, as well as an additional hurdle factor for increasing the shelf life of minimal processed foods.

  14. Immunoregulatory Effects Triggered by Lactic Acid Bacteria Exopolysaccharides: New Insights into Molecular Interactions with Host Cells

    Jonathan Laiño

    2016-08-01

    Full Text Available Researchers have demonstrated that lactic acid bacteria (LAB with immunomodulatory capabilities (immunobiotics exert their beneficial effects through several molecules, including cell wall, peptidoglycan, and exopolysaccharides (EPS, that are able to interact with specific host cell receptors. EPS from LAB show a wide heterogeneity in its composition, meaning that biological properties depend on the strain and. therefore, only a part of the mechanism of action has been elucidated for these molecules. In this review, we summarize the current knowledge of the health-promoting actions of EPS from LAB with special focus on their immunoregulatory actions. In addition, we describe our studies using porcine intestinal epithelial cells (PIE cells as a model to evaluate the molecular interactions of EPS from two immunobiotic LAB strains and the host cells. Our studies showed that EPS from immunobiotic LAB have anti-inflammatory capacities in PIE cells since they are able to reduce the production of inflammatory cytokines in cells challenged with the Toll-like receptor (TLR-4-agonist lipopolysaccharide. The effects of EPS were dependent on TLR2, TLR4, and negative regulators of TLR signaling. We also reported that the radioprotective 105 (RP105/MD1 complex, a member of the TLR family, is partially involved in the immunoregulatory effects of the EPS from LAB. Our work described, for the first time, that LAB and their EPS reduce inflammation in intestinal epithelial cells in a RP105/MD1-dependent manner. A continuing challenge for the future is to reveal more effector-receptor relationships in immunobiotic-host interactions that contribute to the beneficial effects of these bacteria on mucosal immune homeostasis. A detailed molecular understanding should lead to a more rational use of immunobiotics in general, and their EPS in particular, as efficient prevention and therapies for specific immune-related disorders in humans and animals.

  15. Stimulative effect of lactic acid bacteria in the growth of the microalgaeIsochrysis galbana

    Miquel Planas; José Antonio Vázquez; Beatriz Novoa

    2015-01-01

    ABSTRACT Objective:To study the effect of species of lactic acid bacteria (LAB) from telluric origin on the growth of the microalgaeIsochrysis galbana (I. galbana) in small and medium volume flasks. Methods: In the first experiment, 7 LAB species [Carnobacterium piscicola,Lactobacillus brevis,Lactobacillus caseissp.casei, Lactobacillus helveticus, Lactococcus lactisspp. lactis, Leuconostoc mesenteroidesspp. mesenteroides (L. mesenteroidesspp. mesenteroides) andPediococcus acidilactici(P. acidilactici)] were inoculated in 250 mL flasks containing microalgaeI. galbana (106 cells/mL). After fitting the growth data to two mathematical models, twoLAB strains (L. mesenteroidesspp. mesenteroides andP. acidilactici) were selected for the second experiment in which those strains were inoculated in medium size (5 L) volume cultures ofI. galbana (1.2× 105–1.5× 105cells/mL). The bacterial load in cultures from the first experiment was analyzed by plating on marine agar,MRS agar and thiosulfate citrate bile saltssucrose media. Results:All strains ofLAB tested enhanced the growth rate and the final biomass yield ofI. galbana cultures, even in the absence of nutrients in the media. The best overall results and the maximal final cell densities in small flasks were achieved with strainsL. mesenteroides spp. mesenteroides andP. acidilactici, respectively. These two strains also stimulated the growth (40% and 16% with respect to controls) ofI. galbana in medium size volumes. For most strains,CFU values ofLAB remained stable (105–108CFU/mL) for at least 4 days. A high variability was observed in bacteria strains among treatments, withPseudomonas and Moraxella being the most abundant bacteria. Conclusions: The results of present study showed that the growth ofI. galbana in both small and medium size volumes was enhanced byLAB, both in the absence and the presence of nutrients in the culture. The highest final biomass was achieved by addingP. acidilactici, whereas

  16. Genotypic characterization and safety assessment of lactic acid bacteria from indigenous African fermented food products

    Adimpong David B

    2012-05-01

    Full Text Available Abstract Background Indigenous fermented food products play an essential role in the diet of millions of Africans. Lactic acid bacteria (LAB are among the predominant microbial species in African indigenous fermented food products and are used for different applications in the food and biotechnology industries. Numerous studies have described antimicrobial susceptibility profiles of LAB from different parts of the world. However, there is limited information on antimicrobial resistance profiles of LAB from Africa. The aim of this study was to characterize 33 LAB previously isolated from three different African indigenous fermented food products using (GTG5-based rep-PCR, sequencing of the 16S rRNA gene and species-specific PCR techniques for differentiation of closely related species and further evaluate their antibiotic resistance profiles by the broth microdilution method and their haemolytic activity on sheep blood agar plates as indicators of safety traits among these bacteria. Results Using molecular biology based methods and selected phenotypic tests such as catalase reaction, CO2 production from glucose, colonies and cells morphology, the isolates were identified as Lactobacillus delbrueckii, Lactobacillus fermentum, Lactobacillus ghanensis, Lactobacillus plantarum, Lactobacillus salivarius, Leuconostoc pseudomesenteroides, Pediococcus acidilactici, Pediococcus pentosaceus and Weissella confusa. The bacteria were susceptible to ampicillin, chloramphenicol, clindamycin and erythromycin but resistant to vancomycin, kanamycin and streptomycin. Variable sensitivity profiles to tetracycline and gentamicin was observed among the isolates with Lb. plantarum, Lb. salivarius, W. confusa (except strain SK9-5 and Lb. fermentum strains being susceptible to tetracycline whereas Pediococcus strains and Lb. ghanensis strains were resistant. For gentamicin, Leuc. pseudomesenteroides, Lb. ghanensis and Ped. acidilactici strains were resistant to 64

  17. Industrial application of selected lactic acid bacteria isolated from local semolinas for typical sourdough bread production.

    Corona, Onofrio; Alfonzo, Antonio; Ventimiglia, Giusi; Nasca, Anna; Francesca, Nicola; Martorana, Alessandra; Moschetti, Giancarlo; Settanni, Luca

    2016-10-01

    Four obligate heterofermentative lactic acid bacteria (LAB) strains (Weissella cibaria PON10030 and PON10032 and Leuconostoc citreum PON 10079 and PON10080) were tested as single strain starters, mono-species dual strain starters, and multiple strain starter for the preparation and propagation of sourdoughs for the production of a typical bread at industrial level. The kinetics of pH and TTA during the daily sourdough refreshments indicated a correct acidification process for all trials. The concentration of lactic and acetic acid increased consistently during fermentation. The resulting molar ratios between these two organic acids in the experimental trials were lower than those observed in the control trial. The microbiological investigation showed levels of approximately 10(9) CFU/mL in almost all sourdoughs and the comparison of the genetic polymorphisms of the dominating LAB with those of the pure cultures evidenced the persistence of the added strains over time. The resulting breads were evaluated for several quality parameters. The breads with the greatest height were obtained with the quadruple combination of leuconostocs and weissellas. The highest softness was registered for the breads obtained from fermentations performed by W. cibaria PON10032 alone and in combination. The different inocula influenced also the color, the void fraction, the cell density and the mean cell area of the breads. Different levels of acids, alcohols, aldehydes, esters, hydrocarbons, ketones, terpenes, furans and phenol were emitted by the breads. The sensory tests indicated the breads from the sourdoughs fermented with the seven LAB inocula as sweeter and less acidic than control breads and the breads from the trials with the highest complexity of LAB inoculums were those more appreciated by tasters. A multivariate approach found strong differences among the trials. In particular, control breads and the breads obtained with different starter LAB were quite distant and a more

  18. Reduction of Acid-Fast and Non-Acid-Fast Bacteria by Point of Use Coagulation-Flocculation-Disinfection.

    Casanova, Lisa M; Sobsey, Mark D

    2015-11-01

    Point of use (POU) household water treatment is increasingly being adopted as a solution for access to safe water. Non-tuberculous Mycobacteria (NTM) are found in water, but there is little research on whether NTM survive POU treatment. Mycobacteria may be removed by multi-barrier treatment systems that combine processes such as coagulation, settling and disinfection. This work evaluated removal of a non-tuberculous Mycobacterium (Mycobaterium terrae) and a Gram-negative non-acid-fast environmental bacterium (Aeromonas hydrophila) by combined coagulation-flocculation disinfection POU treatment. Aeromonas hydrophila showed 7.7 log10 reduction in demand free buffer, 6.8 log10 in natural surface water, and 4 log10 reduction in fecally contaminated surface water. Turbidity after treatment was coagulant-flocculant-disinfectant in natural water after 30 minutes. The lack of Mycobacteria reduction was similar for both combined coagulant-flocculant-disinfectant and hypochlorite alone. A POU coagulant-flocculant-disinfectant treatment effectively reduced A. hydrophila from natural surface waters but not Mycobacteria. These results reinforce previous findings that POU coagulation-flocculation-disinfection is effective against gram-negative enteric bacteria. POU treatment and safe storage interventions may need to take into account risks from viable NTM in treated stored water and consider alternative treatment processes to achieve NTM reductions. PMID:26580632

  19. Reduction of Acid-Fast and Non-Acid-Fast Bacteria by Point of Use Coagulation-Flocculation-Disinfection

    Lisa M. Casanova

    2015-11-01

    Full Text Available Point of use (POU household water treatment is increasingly being adopted as a solution for access to safe water. Non-tuberculous Mycobacteria (NTM are found in water, but there is little research on whether NTM survive POU treatment. Mycobacteria may be removed by multi-barrier treatment systems that combine processes such as coagulation, settling and disinfection. This work evaluated removal of a non-tuberculous Mycobacterium (Mycobaterium terrae and a Gram-negative non-acid-fast environmental bacterium (Aeromonas hydrophila by combined coagulation-flocculation disinfection POU treatment. Aeromonas hydrophila showed 7.7 log10 reduction in demand free buffer, 6.8 log10 in natural surface water, and 4 log10 reduction in fecally contaminated surface water. Turbidity after treatment was <1 NTU. There was almost no reduction in levels of viable M. terrae by coagulant-flocculant-disinfectant in natural water after 30 minutes. The lack of Mycobacteria reduction was similar for both combined coagulant-flocculant-disinfectant and hypochlorite alone. A POU coagulant-flocculant-disinfectant treatment effectively reduced A. hydrophila from natural surface waters but not Mycobacteria. These results reinforce previous findings that POU coagulation-flocculation-disinfection is effective against gram-negative enteric bacteria. POU treatment and safe storage interventions may need to take into account risks from viable NTM in treated stored water and consider alternative treatment processes to achieve NTM reductions.

  20. Research on application of functional lactic acid bacteria%功能性乳酸菌的应用研究

    湛剑龙; 胡萍; 陈韵; 李立郎; 朱秋劲; 王晓宇; 谢和

    2014-01-01

    Lactic acid bacteria are gram-positive, non-spore, anaerobic, a class of bacteria using carbohy-drates to produce lactic acid, which are valuable resource of microorganisms, and are closely related to our health. This paper described the function of lactic acid bacteria on improving immune, antioxidant, decreasing cholesterol, antihypertensive, antibacterial, and improving the flavor functions, which were currently being used in food and medicines. Some applications were also described such as lactic acid bacteria, genetic engi-neering lactic acid, lactic acid producing enzyme, lactobacillus, lactobacillus starch entrapped and Se lactic acid, so as to provide a reference for the further development and utilization.%乳酸菌是革兰氏阳性,无芽孢,厌氧,利用碳水化合物产生乳酸的一类细菌,是一种宝贵的微生物资源,和我们的健康息息相关。本文介绍了乳酸菌的增强免疫、抗氧化、降胆固醇、抗高血压、抗菌、改善风味等功能,这些功能目前主要被应用于食品和医疗上;还介绍了乳酸菌的一些应用技术,基因工程乳酸菌,乳酸菌产酶,乳酸菌制剂,乳酸菌淀粉包埋以及富硒乳酸菌,为功能性乳酸菌进一步的开发利用提供参考。