The role of colonic metabolism in lactose intolerance

NARCIS (Netherlands)

He, T.; Venema, K.; Priebe, M.G.; Welling, G.W.; Brummer, R.J.M.; Vonk, R.J.

2008-01-01

Lactose maldigestion and intolerance affect a large part of the world population. The underlying factors of lactose intolerance are not fully understood. In this review, the role of colonic metabolism is discussed, i.e. fermentation of lactose by the colonic microbiota, colonic processing of the

Novel products and new technologies for use of a familiar carbohydrate, milk lactose.

Science.gov (United States)

Yang, S T; Silva, E M

1995-11-01

The cheese industry produces large amounts of lactose in the form of cheese whey and whey permeate, generating approximately 27 million tonnes/yr in the US alone. Many uses have been found for whey and lactose, including uses in infant formula; bakery, dairy, and confectionery products; animal feed; and feedstocks for lactose derivatives and several industrial fermentations. Lactose use in food products, however, is somewhat limited because of its low solubility and indigestibility in many individuals. For this reason, lactose is often hydrolyzed before use. Still, demand is insufficient to use all available whey lactose. The result is a low market value for lactose; almost half of the whey produced each year remains unused and is a significant waste disposal problem. Several approaches are possible for transforming lactose into value-added products. For example, galactooligosaccharides can be produce through enzymatic treatments of lactose and may be used as a probiotic food ingredient. Organic acids or xanthan gum may be produced via whey fermentation, and the fermented whey product can be used as a food ingredient with special functionality. This paper reviews the physical characteristics, production techniques, and current uses of lactose, whey, and lactose derivatives. Also examined are novel fermentation and separation technologies developed in our laboratory for the production of lactate, propionate, acetate, and xanthan gum from whey.

Lactose-free frozen yogurt: production and characteristics.

Science.gov (United States)

Skryplonek, Katarzyna; Gomes, David; Viegas, Jorge; Pereira, Carlos; Henriques, Marta

2017-01-01

Nowadays, consumer demand is driving better and more nutritious dairy products. Changing from traditional to new lactose-free products poses technological challenges for the food industry in order to maintain or improve their food characteristics and consumer preferences. This study investigates the production of lactose-free frozen yogurt by enzymati- cally hydrolysis of lactose, and its influence on the final product characteristics. In the case of lactose-free products, commercial Ha-lactase® was used for hydrolysis, and the reaction occurred simultaneously with fermentation. The effect of lactose hydrolysis on the physicochemical properties, texture, viscosity, overrun and sensory attributes in the final product was investigated. After yogurt maturation, the acidity of the lactose-free product was significantly higher than in the control, suggesting that breaking down lactose enhances the fermentation process. Lactose-free frozen yogurt had significantly lower hardness and stickiness and higher viscosity than control frozen yogurt. Moreover, lactose hydrolysis promoted a smooth and creamy consistency, whereas in the case of conventional prod- ucts a coarse structure, due to the presence of large ice crystals, was identified. Hydrolysis of lactose also improved the sweetness and brightness of frozen yogurt. The improved textural properties of lactose-free product results from the fact that monosaccharides produced during lactose hydrolysis depress the freezing point of the mix, which enables product with softer structure and bigger resistance to ice recrystallization to be obtained. The study showed that lactose-free frozen yogurt may be used successfully for production of novel lactose-free frozen desserts. Lactose hydrolysis improves the texture and viscosity of the product,     as well as enhancing its sensory quality.

Hydrolysis of lactose with -D-galactosidase

Directory of Open Access Journals (Sweden)

Vesna Stehlik-Tomas

2001-06-01

Full Text Available The conditions of lactose hydrolysis with enzyme preparation of D-galactosidase were investigated. The aim of this work was to considered the use of whey in fermentative processes with yeast Saccharomyces cerevisiae. Enzymatic hydrolysis was conducted at different temperatures, with different lactose concentrations in medium and different concentrations of added enzyme. The results show that optimal temperature for hydrolysis was 40°C. The optimal amount of enzyme preparation was 2 gL-1 in lactose medium with 5-10 % lactose.

Lactose Intolerance in Adults: Biological Mechanism and Dietary Management.

Science.gov (United States)

Deng, Yanyong; Misselwitz, Benjamin; Dai, Ning; Fox, Mark

2015-09-18

Lactose intolerance related to primary or secondary lactase deficiency is characterized by abdominal pain and distension, borborygmi, flatus, and diarrhea induced by lactose in dairy products. The biological mechanism and lactose malabsorption is established and several investigations are available, including genetic, endoscopic and physiological tests. Lactose intolerance depends not only on the expression of lactase but also on the dose of lactose, intestinal flora, gastrointestinal motility, small intestinal bacterial overgrowth and sensitivity of the gastrointestinal tract to the generation of gas and other fermentation products of lactose digestion. Treatment of lactose intolerance can include lactose-reduced diet and enzyme replacement. This is effective if symptoms are only related to dairy products; however, lactose intolerance can be part of a wider intolerance to variably absorbed, fermentable oligo-, di-, monosaccharides and polyols (FODMAPs). This is present in at least half of patients with irritable bowel syndrome (IBS) and this group requires not only restriction of lactose intake but also a low FODMAP diet to improve gastrointestinal complaints. The long-term effects of a dairy-free, low FODMAPs diet on nutritional health and the fecal microbiome are not well defined. This review summarizes recent advances in our understanding of the genetic basis, biological mechanism, diagnosis and dietary management of lactose intolerance.

Lactose Intolerance in Adults: Biological Mechanism and Dietary Management

Directory of Open Access Journals (Sweden)

Yanyong Deng

2015-09-01

Full Text Available Lactose intolerance related to primary or secondary lactase deficiency is characterized by abdominal pain and distension, borborygmi, flatus, and diarrhea induced by lactose in dairy products. The biological mechanism and lactose malabsorption is established and several investigations are available, including genetic, endoscopic and physiological tests. Lactose intolerance depends not only on the expression of lactase but also on the dose of lactose, intestinal flora, gastrointestinal motility, small intestinal bacterial overgrowth and sensitivity of the gastrointestinal tract to the generation of gas and other fermentation products of lactose digestion. Treatment of lactose intolerance can include lactose-reduced diet and enzyme replacement. This is effective if symptoms are only related to dairy products; however, lactose intolerance can be part of a wider intolerance to variably absorbed, fermentable oligo-, di-, monosaccharides and polyols (FODMAPs. This is present in at least half of patients with irritable bowel syndrome (IBS and this group requires not only restriction of lactose intake but also a low FODMAP diet to improve gastrointestinal complaints. The long-term effects of a dairy-free, low FODMAPs diet on nutritional health and the fecal microbiome are not well defined. This review summarizes recent advances in our understanding of the genetic basis, biological mechanism, diagnosis and dietary management of lactose intolerance.

From 'lactose intolerance' to 'lactose nutrition'.

Science.gov (United States)

Lukito, Widjaja; Malik, Safarina G; Surono, Ingrid S; Wahlqvist, Mark L

2015-01-01

The concept of lactose intolerance has become embedded in Western medicine and developing economy medicine. It is based on evidence that intestinal lactase activity persists into later childhood and throughout life in only a minority of the world's population, notably northern European-derived populations. These people have the T single nucleotide polymorphism (SNP) of the rs49882359 allele (C/T), also known as C/T-13910, the MCM6 gene which positively influences the lactase LCT gene. Other lactase persistent (LP) populations are found in Africa and the Middle East with different genetic variants. These SNPs represent co-evolution with dairying since the agricultural revolution and nutrient-dependent ecological adaptation. That said, gastrointestinal symptoms considered due to small intestinal lactose malabsorption are poorly correlated with lactase non-persistence (LNP), the situation for most people. With LNP, colonic microbiome lactase enables lactose fermentation to occur so that none is found in faeces. Whether the short chain fatty acids (SCFAs) and gases (hydrogen, carbon dioxide and methane) produced cause symptoms is dose-dependent. Up to 25 g of lactose at any one time can usually be consumed by a LNP person, but its food and meal pattern context, the microbiomic characteristics, age and other factors may alter tolerance. Thus, the notion that lactose intolerance is a disorder or disease of LNP people is misplaced and has been one of cultural perspective. What actually matters is whether a particular dairy product as normally consumed give rise to symptoms. It is, therefore, proposed that lactose tolerance tests be replaced with dairy food tolerance tests.

High level production of β-galactosidase exhibiting excellent milk-lactose degradation ability from Aspergillus oryzae by codon and fermentation optimization.

Science.gov (United States)

Zhao, Qianqian; Liu, Fei; Hou, Zhongwen; Yuan, Chao; Zhu, Xiqiang

2014-03-01

A β-galactosidase gene from Aspergillus oryzae was engineered utilizing codon usage optimization to be constitutively and highly expressed in the Pichia pastoris SMD1168H strain in a high-cell-density fermentation. After fermentation for 96 h in a 50-L fermentor using glucose and glycerol as combined carbon sources, the recombinant enzyme in the culture supernatant had an activity of 4,239.07 U mL(-1) with o-nitrophenyl-β-D-galactopyranoside as the substrate, and produced a total of extracellular protein content of 7.267 g L(-1) in which the target protein (6.24 g L(-1)) occupied approximately 86 %. The recombinant β-galactosidase exhibited an excellent lactose hydrolysis ability. With 1,000 U of the enzyme in 100 mL milk, 92.44 % lactose was degraded within 24 h at 60 °C, and the enzyme could also accomplish the hydrolysis at low temperatures of 37, 25, and 10 °C. Thus, this engineered strain had significantly higher fermentation level of A. oryzae lactase than that before optimization and the β-galactosidase may have a good application potential in whey and milk industries.

Modelling of the process yields of a whey fermentation

Energy Technology Data Exchange (ETDEWEB)

Blakebrough, N; Moresi, M

1981-01-01

The biomass yields (y) and COD reduction efficiencies (eta) of a whey fermentation by Kluyveromyces fragilis were studied in a 100-l fermenter at various stirrer speeds and lactose concentrations, and compared to those obtained in 10-l and 15-l fermenters at constant values of the oxygen transfer coefficient (kla) and air velocity. The empirical models previously constructed by using the 15-l fermenter data could be used to predict the yields on the other scales by calculating for each run the 15-l fermenter which would provide the same oxygen transfer coefficient measured by the sulfite method on each fermenter under study. To make this model independent of stirrer speeds used in each generic fermenter, the effect of aeration and mixing was incorporated into an overall parameter (kla) and the values of y and eta were correlated only with temperature, lactose level and kla, since these variables were approximately orthogonal. The validity of this model was finally checked against the yields reported by Wasserman et al. (1961) in a 6-cubic metre fermenter, thus confirming the capability of the model to provide a reliable basis for further scale-up on the production scale. (Refs. 17).

A biochemically structured model for ethanol fermentation by Kluyveromyces marxianus: A batch fermentation and kinetic study

DEFF Research Database (Denmark)

Sansonetti, Sascha; Hobley, Timothy John; Calabrò, V.

2011-01-01

Anaerobic batch fermentations of ricotta cheese whey (i.e. containing lactose) were performed under different operating conditions. Ethanol concentrations of ca. 22gL−1 were found from whey containing ca. 44gL−1 lactose, which corresponded to up to 95% of the theoretical ethanol yield within 15h......, lactose, biomass and glycerol during batch fermentation could be described within a ca. 6% deviation, as could the yield coefficients for biomass and ethanol produced on lactose. The model structure confirmed that the thermodynamics considerations on the stoichiometry of the system constrain the metabolic...... coefficients within a physically meaningful range thereby providing valuable and reliable insight into fermentation processes....

Mini review on role of β-galactosidase in lactose intolerance

Science.gov (United States)

A, Nivetha; V, Mohanasrinivasan

2017-11-01

This review mainly focuses on the role and properties of β-galactosidase in lactose intolerance and its industrial application. β-Galactosidase, hydrolyses the lactose into glucose and galactose and it is most commonly used in food based technology, particularly in the dairy manufacturing industry. This catalyst mainly focus for the improvement of new and novel products with hydrolyzed lactose, which can be appropriate for the lactose-intolerant persons, to improve the technological, texture and scientific properties of non-fermented dairy products. β-Galactosidase derived from the group of saccharides which is a converting enzymes in the family of hydrolases. They are broadly distributed in the several biological living systems. The enzymatic hydrolysis of lactose is also preferred in food based technology due to the low soluble range of lactose. The concentration lactose was found to be high in fermented dairy products such as ice cream, butter, cheese curd, yogurt, etc., can prompt extreme lactose crystallization bringing about items through a coarse, abrasive surface. Lactose hydrolysis in dairy products enhances adaptability also, richness altogether. These products are extra edible. Also for this purpose, the utilization of β-galactosidase enzyme prior to the condensing operation can reduce the lactose content to a point where lactose was no longer a problem industrial application of β-galactosidase. In Industries, due to the positive and constructive effect on intestinal bacterial microflora, different types of applications are possible in β-galactosidase enzyme.

Industrial alcohol production via whey and grain fermentation

Energy Technology Data Exchange (ETDEWEB)

Friend, B A; Cunningham, M L; Shahani, K M

1982-01-01

Six strains of a trained lactose fermenting Kluyveromyces yeast were examined for their ability to utilise lactose in sweet-whey permeate. All strains of K. fragilis tested reduced the concentration of the 5.1% lactose, initially present in whey permeate, to 0.1-0.2% within 48h. Periodic adjustment to maintain the pH during fermentation did not alter the lactose utilisation. The fermentation efficiency of K. fragilis was then compared with that of a mixture of K. fragilis and the classical alcohol fermenter Saccharomyces cerevisiae to verify that no unfavourable interactions occurred in the mixed culture. There were no differences in lactose utilisation or ethanol production between the two groups; both produced approximately 2% ethanol within 24h. This represented approximately 80% of the alcohol which theoretically could be produced from the 5.1% lactose present in the permeate. Whey permeate was also incorporated into the classical grain fermentation by substitution for one-half the water normally added to produce the mash. Fermentation was nearly complete by 36h and alcohol levels ranged from 9.7% for the mixed culture to 9.4% for the K. fragilis and 9.3% for the S. cerevisiae. Since the whey provided significant levels of fermentable sugars, studies were also conducted in which undiluted whey permeate was substituted for all of the water in the mash and the amount of grain was reduced by 20%. At the end of 36h K. fragilis produced 10.9% alcohol and at 60 h of fermentation the level had reached 12.2%. When whole sweet-whey was used, similar levels of alcohol were produced. (Refs. 20).

Acute and Chronic Effects of Dietary Lactose in Adult Rats Are not Explained by Residual Intestinal Lactase Activity.

Science.gov (United States)

van de Heijning, Bert J M; Kegler, Diane; Schipper, Lidewij; Voogd, Eline; Oosting, Annemarie; van der Beek, Eline M

2015-07-08

Neonatal rats have a high intestinal lactase activity, which declines around weaning. Yet, the effects of lactose-containing products are often studied in adult animals. This report is on the residual, post-weaning lactase activity and on the short- and long-term effects of lactose exposure in adult rats. Acutely, the postprandial plasma response to increasing doses of lactose was studied, and chronically, the effects of a 30% lactose diet fed from postnatal (PN) Day 15 onwards were evaluated. Intestinal lactase activity, as assessed both in vivo and in vitro, was compared between both test methods and diet groups (lactose vs. control). A 50%-75% decreased digestive capability towards lactose was observed from weaning into adulthood. Instillation of lactose in adult rats showed disproportionally low increases in plasma glucose levels and did not elicit an insulin response. However, gavages comprising maltodextrin gave rise to significant plasma glucose and insulin responses, indicative of a bias of the adult GI tract to digest glucose polymers. Despite the residual intestinal lactase activity shown, a 30% lactose diet was poorly digested by adult rats: the lactose diet rendered the animals less heavy and virtually devoid of body fat, whereas their cecum tripled in size, suggesting an increased bacterial fermentation. The observed acute and chronic effects of lactose exposure in adult rats cannot be explained by the residual intestinal lactase activity assessed.

Simultaneous enzymatic hydrolysis and lactic fermentation to obtain a yogurt with low lactose content Hidrólise enzimática e fermentação lática simultâneas na obtenção de um iogurte com baixo teor de lactose

Directory of Open Access Journals (Sweden)

André Rosa Martins

2012-10-01

Full Text Available In a single-stage process with the simultaneous addition of β-galactosidase and lactic culture, the lactose conversion, the processing time, viscosity and syneresis were evaluated. Fermentation was promoted by lactic culture containing two probiotic microorganisms, Bifidobacterium animalis and Lactobacillus acidophilus, associated with the typical microorganisms of yogurt. An enzymatic preparation containing β-galactosidases from Kluyveromyces lactis and Aspergillus niger was used. A central composite design (2³ trials plus three central points was proposed in order to evaluate the effects of initial lactose concentration, enzyme concentration and the time of addition of the enzyme. The following conditions were established: initial lactose concentration of 91 g L-1, enzyme concentration of 0.5 g L-1 and enzyme addition at the beginning of fermentation. In these conditions, a decrease in processing time (from 4.55 to 3.68 h and an increase in lactose conversion (from 15.2 to 97.9% were observed in relation to the fermentation without enzyme addition, and no detrimental changes in some physical properties of yogurt (viscosity, and syneresis.No processo em um único estágio com a adição simultânea de β-galactosidase e de cultura lática, foram avaliadas a conversão da lactose, o tempo de processamento, a viscosidade e a sinérese. A fermentação foi promovida por cultura láctica, contendo dois micro-organismos probióticos, Bifidobacterium animalis e Lactobacillus acidophilus, associados aos micro-organismos característicos do iogurte. Foi utilizado um preparado enzimático contendoβ-galactosidases obtidas de Kluyveromyces lactis e de Aspergillus niger. Os efeitos da concentração inicial de lactose, concentração de enzima e tempo de adição da enzima foram avaliados por meio de um planejamento experimental (2³ ensaios mais três pontos centrais. As seguintes condições foram estabelecidas: concentração inicial de lactose de

Impact of short-chain galactooligosaccharides on the gut microbiome of lactose-intolerant individuals.

Science.gov (United States)

Azcarate-Peril, M Andrea; Ritter, Andrew J; Savaiano, Dennis; Monteagudo-Mera, Andrea; Anderson, Carlton; Magness, Scott T; Klaenhammer, Todd R

2017-01-17

Directed modulation of the colonic bacteria to metabolize lactose effectively is a potentially useful approach to improve lactose digestion and tolerance. A randomized, double-blind, multisite placebo-controlled trial conducted in human subjects demonstrated that administration of a highly purified (>95%) short-chain galactooligosaccharide (GOS), designated "RP-G28," significantly improved clinical outcomes for lactose digestion and tolerance. In these individuals, stool samples were collected pretreatment (day 0), after GOS treatment (day 36), and 30 d after GOS feeding stopped and consumption of dairy products was encouraged (day 66). In this study, changes in the fecal microbiome were investigated using 16S rRNA amplicon pyrosequencing and high-throughput quantitative PCR. At day 36, bifidobacterial populations were increased in 27 of 30 of GOS subjects (90%), demonstrating a bifidogenic response in vivo. Relative abundance of lactose-fermenting Bifidobacterium, Faecalibacterium, and Lactobacillus were significantly increased in response to GOS. When dairy was introduced into the diet, lactose-fermenting Roseburia species increased from day 36 to day 66. The results indicated a definitive change in the fecal microbiome of lactose-intolerant individuals, increasing the abundance of lactose-metabolizing bacteria that were responsive to dietary adaptation to GOS. This change correlated with clinical outcomes of improved lactose tolerance.

Characterization of the Lactococcus lactis lactose genes and regulation of their expression

NARCIS (Netherlands)

Rooijen, van R.J.

1993-01-01

An important trait of the lactic acid bacterium Lactococcus lactis , that is used in industrial dairy fermentations, is the conversion of lactose into lactic acid. The enzymatic steps involved in the breakdown of lactose, that is transported into the cell via a

Prevalence of Lactose Malabsorption and Lactose Intolerance in Pediatric Patients with Selected Gastrointestinal Diseases.

Science.gov (United States)

Pawłowska, Katarzyna; Umławska, Wioleta; Iwańczak, Barbara

2015-01-01

Lactase is an enzyme involved in the hydrolysis of lactose. Deficiency of the enzyme (hypolactasia) may be determined genetically or arise secondarily to disease of small intestine. Under this condition, lactose enters the colon where it is fermented by intestinal microflora and turns to gases and short-chain fatty acids, causing gastrointestinal symptoms known as lactose intolerance (LI). To investigate the incidence of lactose malabsorption (LM), LI and the coexistence of these two conditions in children with upper gastrointestinal tract diseases (UGTD), malabsorption syndrome, inflammatory bowel disease (IBD) and functional gastrointestinal disorders (FGID). Hydrogen breath test (HBT) was conducted in 387 pediatric patients in years 2010-2013. Two hundred thirty two children with gastrointestinal tract diseases were selected and assigned to groups - UGTD, malabsorption syndrome, IBD or FGID. For each group the frequency of LM, frequency and severity of LI and the frequency of their co-occurrence were calculated. Lactose malabsorption was observed in 37.08% of patients with gastrointestinal diseases. Positive HBT result was the most common in children with malabsorption syndrome (52.50%) and less common in UGTD (30.85%), especially in ulcer disease (23.53%). Symptoms after lactose ingestion affected 36.64% of the subjects, and were more specific to lactose malabsorbers than to lactose absorbers (72.10% vs. 15.75%). The higher frequency of LI was noted in children with FGID, especially in irritable bowel syndrome (IBS) (65.22%). The lowest incidence of symptoms was obtained in children with UGTD, especially in those with ulcer disease (27.44%). The incidence of LM with LI was noted in 27.16% of all patients and was the highest in IBS (47.83%) and the lowest in ulcer disease (15.78%). Lactose malabsorption is a common problem in children with gastrointestinal diseases, especially in children with bowel diseases. Lactose intolerance is related to LM, but does not

Butanol production from concentrated lactose/whey permeate: Use of pervaporation membrane to recover and concentrate product

Science.gov (United States)

In these studies butanol (acetone butanol ethanol, or ABE) was produced from concentrated lactose/whey permeate containing 211 gL-1 lactose. Fermentation of such a highly concentrated lactose solution was possible due to simultaneous product removal using a pervaporation membrane. In this system a p...

Optimization and shelf life of a low-lactose yogurt with Lactobacillus rhamnosus HN001.

Science.gov (United States)

Ibarra, A; Acha, R; Calleja, M-T; Chiralt-Boix, A; Wittig, E

2012-07-01

Lactose intolerance results in gastrointestinal discomfort and the malabsorption of certain nutrients, such as calcium. The replacement of milk with low-lactose and probiotic-enriched dairy products is an effective strategy of mitigating the symptoms of lactose intolerance. Lactobacillus rhamnosus HN001 (HN001) is a safe, immunity-stimulating probiotic. We have developed a process to increase the hydrolysis of lactose and HN001 growth in yogurt versus β-galactosidase (βG) concentration and enzymatic hydrolysis time (EHT) before bacterial fermentation. The objective of this study was to optimize the conditions by which yogurt is processed as a function of βG and EHT using a multifactorial design, with lactose content, HN001 growth, process time, and sensory quality as dependent variables. Further, the shelf life of the optimized yogurt was evaluated. In the optimization study, polynomials explained the dependent variables. Based on Pearson correlation coefficients, HN001 growth correlated positively with the hydrolysis of lactose. However, low lactose content and high HN001 count increased the fermentation time and lowered the sensory quality. The optimized conditions-using polynomials to obtain yogurt with >1 × 10(7) cfu of HN001/mL, yogurt to which HN001 has been added for lactose-intolerant persons who wish to strengthen their immune system. Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Effect of multiple substrates in ethanol fermentations from cheese whey

Energy Technology Data Exchange (ETDEWEB)

Wang, C J; Jayanata, Y; Bajpai, R K

1987-01-01

Ethanol fermentations from cheese whey by Kluyveromyces marxianus CBS 397 were investigated. Cheese whey, which contains lactose as the major sugar, has been found to have small amounts of glucose and galactose, depending on the source and operating conditions. Fermentation performance was strongly influenced by the presence of glucose and galactose. However, lactose did not significantly affect the cell growth and product formation even at a high concentration. A logistical model was proposed to take into account the effect of lactose. (Refs. 6).

Novel technology development through thermal drying of encapsulated Kluyveromyces marxianus in micro- and nano-tubular cellulose in lactose fermentation and its evaluation for food production.

Science.gov (United States)

Papapostolou, Harris; Servetas, Yiannis; Bosnea, Loulouda A; Kanellaki, Maria; Koutinas, Athanasios A

2012-12-01

A novel technology development based on the production of a low-cost starter culture for ripening of cheeses and baking is reported in the present study. The starter culture comprises thermally dried cells of Kluyveromyces marxianus encapsulated in micro- and nano-tubular cellulose. For production of a low-cost and effective biocatalyst, whey was used as raw material for biomass production and thermal drying methods (convective, conventional, and vacuum) were applied and evaluated at drying temperatures ranging from 35 to 60 °C. The effect of drying temperature of biocatalysts on fermentability of lactose and whey was evaluated. Storage stability and suitability of biocatalysts as a commercial starter cultures was also assessed and evaluated. All thermally dried biocatalysts were found to be active in lactose and whey fermentation. In all cases, there was sugar conversion ranging from 92 to 100 %, ethanol concentration of up to 1.47 % (v/v), and lactic acid concentrations ranged from 4.1 to 5.5 g/l. However, convective drying of the encapsulated cells of K. marxianus in micro- and nano-tubular cellulose was faster and a more effective drying method while drying at 42 °C appear to be the best drying temperature in terms of cell activity, ethanol, and lactic acid formation. Storage of the biocatalysts for 3 months at 4 °C proved maintenance of its activity even though fermentation times increased by 50-100 % compared with the fresh dried ones.

Production of citric acid from whey permeate by fermentation using Aspergillus niger

Energy Technology Data Exchange (ETDEWEB)

Hossain, M; Brooks, J D

1983-08-01

The use of lactic casein whey permeate as a substrate for citric acid production by fermentation has been investigated. Using a mutant strain of Aspergillus niger IMI 41874 in fermenter culture, a citric acid concentration of 8.3 g/l, representing a yield of 19% (w/w) based on lactose utilized, has been observed. Supplementation of the permeate with lactose (final concentration 140 g/l) increased the production to 14.8 g/l (yield 23%). The natural pH of the permeate (pH 4.5) was the most suitable initial pH for the process, and pH control during the fermentation was unnecessary. The addition of methanol (final concentration 3% v/v) to the fermentation increased the citric acid production to 25 g/l (yield 33%, based on lactose utilized). 13 references.

Comparison of HPLC-RI, LC/MS-MS and enzymatic assays for the analysis of residual lactose in lactose-free milk.

Science.gov (United States)

Trani, A; Gambacorta, G; Loizzo, P; Cassone, A; Fasciano, C; Zambrini, A V; Faccia, M

2017-10-15

Lactose intolerance is the decreased ability to digest lactose, and the population involved is rapidly increasing all over the world. Different procedures have been reported in the literature to quantify lactose in dairy products, but the official method of analysis is based on enzymatic assay. In this paper, the effectiveness of two enzymatic kits in detecting residual lactose in lactose-free milk was investigated, and a comparison with two alternative chromatographic methods was done. The investigation used several samples of UHT milk containing different levels of lactose, and the results highlighted the inadequacy of the enzymatic assays and of the HPLC-RI method to analyse lactose-free milk. An LC-MS/MS method using the formate adduct was developed, and it allowed quantitation of lactose and lactulose in all samples at a high level of precision and repeatability. Copyright © 2017 Elsevier Ltd. All rights reserved.

Enterobacter sp. LU1 as a novel succinic acid producer - co-utilization of glycerol and lactose.

Science.gov (United States)

Podleśny, Marcin; Jarocki, Piotr; Wyrostek, Jakub; Czernecki, Tomasz; Kucharska, Jagoda; Nowak, Anna; Targoński, Zdzisław

2017-03-01

Succinic acid is an important C4-building chemical platform for many applications. A novel succinic acid-producing bacterial strain was isolated from goat rumen. Phylogenetic analysis based on the 16S rRNA sequence and physiological analysis indicated that the strain belongs to the genus Enterobacter. This is the first report of a wild bacterial strain from the genus Enterobacter that is capable of efficient succinic acid production. Co-fermentation of glycerol and lactose significantly improved glycerol utilization under anaerobic conditions, debottlenecking the utilization pathway of this valuable biodiesel waste product. Succinic acid production reached 35 g l -1 when Enterobacter sp. LU1 was cultured in medium containing 50 g l -1 of glycerol and 25 g l -1 of lactose as carbon sources. © 2016 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

Modelling of the process yields of a whey fermentation

Energy Technology Data Exchange (ETDEWEB)

Blakebrough, N; Moresi, M

1981-09-01

The biomass yields (y) and COD reduction efficiencies (eta) of a whey fermentation by Kluyveromyces fragilis were studied in a 100-l fermenter at various stirrer speeds and lactose concentrations, and compared to those obtained in 10-l and 15-l fermenters at constant values of the oxygen transfer coefficient (ksub(L)a) and air velocity. The empirical models previously constructed by using the 15-l fermenter data could be used to predict the yields on the other scales by calculating for each run the 15-l fermenter which would provide the same oxygen transfer coefficient measured by the sulphite method on each fermenter under study. To make this model independent of stirrer speeds used in each generic fermenter, the effect of aeration and mixing was incorporated into an overall parameter (ksub(L)a) and the values of y and eta were correlated only with temperature, lactose level and ksub(L)a since these variables were approximately orthogonal.

The effects of probiotics in lactose intolerance: A systematic review.

Science.gov (United States)

Oak, Sophia J; Jha, Rajesh

2018-02-09

Over 60 percent of the human population has a reduced ability to digest lactose due to low levels of lactase enzyme activity. Probiotics are live bacteria or yeast that supplements the gastrointestinal flora. Studies have shown that probiotics exhibit various health beneficial properties such as improvement of intestinal health, enhancement of the immune responses, and reduction of serum cholesterol. Accumulating evidence has shown that probiotic bacteria in fermented and unfermented milk products can be used to alleviate the clinical symptoms of lactose intolerance (LI). In this systematic review, the effectiveness of probiotics in the treatment of LI was evaluated using 15 randomized double-blind studies. Eight probiotic strains with the greatest number of proven benefits were studied. Results showed varying degrees of efficacy but an overall positive relationship between probiotics and lactose intolerance.

Accelerated fermentation of cheese whey. Developing the system

Energy Technology Data Exchange (ETDEWEB)

Bechtle, R M; Claydon, T J

1971-01-01

A system for accelerated fermentation of cheese wheys requires a mixed yeast and lactose-fermenting bacterial culture. The air flow required (110 ml/min/1./1% of lactose) was proportional to the concentration of wheys in the media. Yeast cell-mass production by accelerated fermentation was equal to or greater than the whey concentration factor when compared with yeast production of single yeast strain production on unconcentrated wheys. Generally, on triple strength wheys, yeast production was approximately 1 lb/gallon of medium. Fermentation media formulas were developed with whey analysis, shake culture, and fermentor trials. The formula used with a specific whey must be adequate to supplement the mineral deficiencies in the whey and to provide trace elements and nutrients essential for maximum microbial growth. High-rate aeration was required for both respiration of the microbial culture and to purge the ferment of volatile metabolites, whose presence depressed microbial cell synthesis.

Clinical implications of lactose malabsorption versus lactose intolerance.

Science.gov (United States)

Levitt, Michael; Wilt, Timothy; Shaukat, Aasma

2013-07-01

The majority of the world's adult population and an estimated 80 million Americans are hypolactasic and hence malabsorb ingested lactose. Although lactose malabsorption is easily identified, less readily assessed is the clinically important question of how often does this malabsorption induce symptoms. This review summarizes: (1) knowledge concerning the etiology and diagnosis of hypolactasia and the pathophysiology of the symptoms of lactose malabsorption and (2) the results of well-controlled trials of the symptomatic response of lactose malabsorbers to varying dosages of lactose and the efficacy of therapeutic interventions to alleviate these symptoms. We conclude that the clinical significance of lactose malabsorption has been overestimated by both the lay public and physicians in that commonly ingested doses of lactose (ie, the quantity in a cup of milk) usually do not cause perceptible symptoms when ingested with a meal. Symptoms occur when the lactose dosage exceeds that in a cup of milk or when lactose is ingested without other nutrients. Simple dietary instruction, rather than the use of commercial products to reduce lactose intake, is recommended for the vast majority of lactose-malabsorbing subjects.

Lactose Intolerance

Science.gov (United States)

Lactose intolerance means that you cannot digest foods with lactose in them. Lactose is the sugar found in ... find out if your problems are due to lactose intolerance. Lactose intolerance is not serious. Eating less food ...

Lactose digestion from yogurt: mechanism and relevance.

Science.gov (United States)

Savaiano, Dennis A

2014-05-01

Yogurt is traditionally consumed throughout the world among populations who are seemingly unable to digest lactose. This review provides a historical overview of the studies that show lactose digestion and tolerance from yogurt by lactose-intolerant people. The lactose in yogurt is digested more efficiently than other dairy sources of lactose because the bacteria inherent in yogurt assist with its digestion. The bacterial lactase survives the acidic conditions of the stomach, apparently being physically protected within the bacterial cells and facilitated by the buffering capacity of yogurt. The increasing pH as the yogurt enters the small intestine and a slower gastrointestinal transit time allow the bacterial lactase to be active, digesting lactose from yogurt sufficiently to prevent symptoms in lactose-intolerant people. There is little difference in the lactase capability of different commercial yogurts, because they apparently contain Lactobacillus bulgaricus and Streptococcus thermophilus in sufficient quantities (10(8) bacteria/mL). However, Lactobacillus acidophilus appears to require cell membrane disruption to physically release the lactase. Compared with unflavored yogurts, flavored yogurts appear to exhibit somewhat reduced lactase activity but are still well tolerated.

Ethanol Production from Whey by Kluyveromyces marxianus in Batch Fermentation System: Kinetics Parameters Estimation

Directory of Open Access Journals (Sweden)

Dessy Ariyanti

2013-03-01

Full Text Available Whey is the liquid remaining after milk has been curdled and strained. It is a by-product of the manufacture of cheese or casein and has several commercial uses. In environmental point of view, whey is kind of waste which has high pollution level due to it’s contain high organic compound with BOD and COD value 50 and 80 g/L respectively. On the other side, whey also contain an amount of lactose (4.5%-5%; lactose can be used as carbon source and raw material for producing ethanol via fermentation using yeast strain Kluyveromyces marxianus. The objective of this research is to investigate the ethanol production kinetics from crude whey through fermentation using Kluyveromyces marxianus and to predict the model kinetics parameter. The yeast was able to metabolize most of the lactose within 16 h to give 8.64 g/L ethanol, 4.43 g/L biomass, and remain the 3.122 g/L residual lactose. From the results presented it also can be concluded that common kinetic model for microbial growth, substrate consumption, and product formation is a good alternative to describe an experimental batch fermentation of Kluyveromyces marxianus grown on a medium composed of whey. The model was found to be capable of reflecting all batch culture phases to a certain degree of accuracy, giving the parameter value: μmax, Ks, YX/S, α, β : 0.32, 10.52, 0.095, 1.52, and 0.11 respectively. © 2013 BCREC UNDIP. All rights reserved(Selected Paper from International Conference on Chemical and Material Engineering (ICCME 2012Received: 27th September 2012; Revised: 29th November 2012; Accepted: 7th December 2012[How to Cite: D. Ariyanti, H. Hadiyanto, (2013. Ethanol Production from Whey by Kluyveromyces marxianus in Batch Fermentation System: Kinetics Parameters Estimation. Bulletin of Chemical Reaction Engineering & Catalysis, 7 (3: 179-184. (doi:10.9767/bcrec.7.3.4044.179-184][Permalink/DOI: http://dx.doi.org/10.9767/bcrec.7.3.4044.179-184 ] View in  |

[Lactose-containing tablets for patients with lactose intolerance?].

Science.gov (United States)

Picksak, Gesine; Stichtenoth, Dirk O

2009-01-01

Lactose is often used as an excipient in tablets because of its ideal characteristics. Most patients with lactose intolerance tolerate small amounts of lactose. However, the nocebo effect must be considered. Thus, patients should be informed about the very small amounts of lactose in the medication. If the patient is still suffering from gastrointestinal symptoms and there is no lactose-free alternative, the enzyme lactase can be substituted individually.

Lactose/whey utilization and ethanol production by transformed Saccharomyces cerevisiae cells.

Science.gov (United States)

Porro, D; Martegani, E; Ranzi, B M; Alberghina, L

1992-04-05

Strains of Saccharomyces cerevisiae transformed with a multicopy expression vector bearing both the Escherichia coli beta-galactosidase gene under the control of the upstream activating sequence of the GAL1-10 genes and the GAL4 activator gene release part of beta-galactosidase in the growth medium. This release is due to cell lysis of the older mother cells; the enzyme maintains its activity in buffered growth media. Fermentation studies with transformed yeast strains showed that the release of beta-galactosidase allowed an efficient growth on buffered media containing lactose as carbon source as well as on whey-based media. The transformed strains utilized up to 95% of the lactose and a high growth yield was obtained in rich media. High productions of ethanol were also observed in stationary phase after growth in lactose minimal media.

Subjective perception of lactose intolerance does not always indicate lactose malabsorption.

Science.gov (United States)

Casellas, Francesc; Aparici, Anna; Casaus, Maite; Rodríguez, Purificación; Malagelada, Juan R

2010-07-01

Symptomatic lactose intolerance is common; however, abdominal symptoms that patients experience after ingestion of lactose-containing foods can have causes beyond lactose malabsorption. We aimed to determine whether symptoms that patients usually attribute to lactose intolerance are comparable to symptoms provoked by a controlled lactose challenge and whether these symptoms are related to lactose absorption capacity. We performed an observational, prospective, transverse study of 353 patients referred for a lactose hydrogen breath test (HBT). Patients completed a validated questionnaire about symptoms associated with consumption of dairy products at home (home symptoms). After a 50-g lactose breath test, they completed the same questionnaire again (lactose challenge symptoms). Patients were assigned to groups of absorbers or malabsorbers according to HBT results and tolerants or intolerants according to the results of the questionnaire. The total symptom score was significantly higher for home symptoms than for the lactose challenge (16 vs 8, P lactose challenge for lactose absorbers compared with malabsorbers (16 vs 4, P lactose tolerants compared with intolerants (12 vs 2, P lactose intolerance at home was similar in men and women. Daily life symptoms that patients associate with lactose intolerance are often unrelated to lactose malabsorption. Even among true lactose malabsorbers, symptom recall tends to be amplified by the patient. Thus, conventional anamnesis is a highly unreliable tool to establish symptomatic lactose malabsorption. Copyright (c) 2010 AGA Institute. Published by Elsevier Inc. All rights reserved.

Surface area of lactose and lactose granulates on consolidation and compaction

OpenAIRE

Riepma, Klaas Alouis

1993-01-01

This dissertation discusses the effect of short time storage at different conditions on the strength and the specific BET surface area of lactose tablets. In addition, some aspects are studied of the consolidation and compaction properties of crystalline lactose fractions in heterogeneous systems. The crystalline lactose types used are: a-lactose monohydrate, anhydrous a-lactose, crystalline B-lactose and roller dried B-lactose. ... Zie: Summary

Impact of lactose starvation on the physiology of Lactobacillus casei GCRL163 in the presence or absence of tween 80.

Science.gov (United States)

Al-Naseri, Ali; Bowman, John P; Wilson, Richard; Nilsson, Rolf E; Britz, Margaret L

2013-11-01

The global proteomic response of the nonstarter lactic acid bacteria Lactobacillus casei strain GCRL163 under carbohydrate depletion was investigated to understand aspects of its survival following cessation of fermentation. The proteome of L. casei GCRL163 was analyzed quantitatively after growth in modified MRS (with and without Tween 80) with different levels of lactose (0% lactose, starvation; 0.2% lactose, growth limiting; 1% lactose, non-growth-limited control) using gel-free proteomics. Results revealed that carbohydrate starvation lead to suppression of lactose and galactose catabolic pathways as well as pathways for nucleotide and protein synthesis. Enzymes of the glycolysis/gluconeogenesis pathway, amino acid synthesis, and pyruvate and citrate metabolism become more abundant as well as other carbohydrate catabolic pathways, suggesting increased optimization of intermediary metabolism and scavenging. Tween 80 did not affect growth yield; however, proteins related to fatty acid biosynthesis were repressed in the presence of Tween 80. The data suggest that L. casei adeptly switches to a scavenging mode, using both citrate and Tween 80, and efficiently adjusts energetic requirements when carbohydrate starved and thus can sustain survival for weeks to months. Explaining the adaptation of L. casei during lactose starvation will assist efforts to maintain viability of L. casei and extend its utility as a beneficial dietary adjunct and fermentation processing aid.

Optimization of fermentation conditions for ethanol production from whey

Energy Technology Data Exchange (ETDEWEB)

Castillo, F J; Izaguirre, M F; Michelena, V; Moreno, B

1982-01-01

Optimal conditions for ethanol production in 7% whey solutions by the yeast Candida pseudotropicalis ATCC 8619 included an initial pH of 4.57 and 30 degrees. Complete fermentation of the available lactose took place without supplementary nutrients; additions of N and P salts, yeast extract, or corn steep liquor resulted in increased yeast production and lower ethanol yields. A possible correlation was observed between increases in yeast inocula and lactose utilization and ethanol production rates; 8.35 g ethanol/L was obtained within 22 hours by using a yeast inoculum of 13.9 g/L. No differences in fermentation rates or ethanol yields were observed when whole or deproteinized whey solutions were used. Concentrated whey permeates, obtained after removal of the valuable proteins from whey, can be effectively fermented for ethanol production.

Is it possible to find presence of lactose in pharmaceuticals? - Preliminary studies by ATR-FTIR spectroscopy and chemometrics

Science.gov (United States)

Banas, A.; Banas, K.; Kalaiselvi, S. M. P.; Pawlicki, B.; Kwiatek, W. M.; Breese, M. B. H.

2017-01-01

Lactose and saccharose have the same molecular formula; however, the arrangement of their atoms is different. A major difference between lactose and saccharose with regard to digestion and processing is that it is not uncommon for individuals to be lactose intolerant (around two thirds of the population has a limited ability to digest lactose after infancy), but it is rather unlikely to be saccharose intolerant. The pharmaceutical industry uses lactose and saccharose as inactive ingredients of drugs to help form tablets because of their excellent compressibility properties. Some patients with severe lactose intolerance may experience symptoms of many allergic reactions after taking medicine that contains this substance. People who are specifically "allergic" to lactose (not just lactose intolerant) should not use tablets containing this ingredient. Fourier Transform Infrared (FTIR) spectroscopy has a unique chemical fingerprinting capability and plays a significant important role in the identification and characterization of analyzed samples and hence has been widely used in pharmaceutical science. However, a typical FTIR spectrum collected from tablets contains a myriad of valuable information hidden in a family of tiny peaks. Powerful multivariate spectral data processing can transform FTIR spectroscopy into an ideal tool for high volume, rapid screening and characterization of even minor tablet components. In this paper a method for distinction between FTIR spectra collected for tablets with or without lactose is presented. The results seem to indicate that the success of identifying one component in FTIR spectra collected for pharmaceutical composition (that is tablet) is largely dependent on the choice of the chemometric technique applied.

Improved ethanol production from whey Saccharomyces cerevisiae using permeabilized cells of Kluyveromyces marxianus

Energy Technology Data Exchange (ETDEWEB)

Rosenberg, M [Slovak Technical Univ., Bratislava (Slovakia). Dept. of Biochemical Technology; Tomaska, M [Slovak Technical Univ., Bratislava (Slovakia). Dept. of Biochemical Technology; Kanuch, J [Slovak Technical Univ., Bratislava (Slovakia). Dept. of Biochemical Technology; Sturdik, E [Slovak Technical Univ., Bratislava (Slovakia). Dept. of Biochemical Technology

1996-12-31

Permeabilized cells of Kluyveromyces marxianus CCY eSY2 were tested as the source of lactase in the ethanol fermentation of concentrated deproteinized whey (65-70 g/l lactose) by Saccharomyces cerevisiae CCY 10-13-14. Rapid lactose hydrolysis by small amounts of permeabilized cells following the fermentation of released glucose and galactose by S. cerevisiae resulted in a twofold enhancement of the overall volumetric productivity (1.03 g/lxh), compared to the fermentation in which the lactose was directly fermented by K. marxianus. (orig.)

The use of a thermotolerant fermentative Kluyveromyces marxianus IMB3 yeast strain for ethanol production

Energy Technology Data Exchange (ETDEWEB)

Banat, I.M. [Univ. of the United Arab Emirates, Al-Ain (United Arab Emirates). Dept. of Biolology; Singh, D. [Haryana Agriculture Univ., Hisar (India). Dept. of Microbiology; Marchant, R. [Ulster Univ. (United Kingdom). School of Applied Biological and Chemical Sciences

1996-12-31

An investigation was carried out on the growth and ethanol production of a novel thermotolerant ethanol-producing Kluyveromyces marxianus IMB3 yeast strain. It grew aerobically on glucose, lactose, cellobiose, xylose and whey permeate and fermented all the above carbon sources to ethanol at 45 C. This strain was capable of growing under anaerobic chemostat fermentation conditions at 45 C and a dilution rate of 0.15 h{sup -1} and produced {<=}0.9 g/l biomass and 1.8% (v/v) ethanol. An increase in biomass (up to 10.0 g/l) and ethanol (up to 4.3% v/v at 45 C and 7.7% v/v at 40 C) were achieved by applying a continuous two-stage fermentation in sequence (one aerobic and one anerobic stage) or a two-stage anaerobic fermentation with cell recycling. Potential applications, involving alcohol production systems, for use in dairy and wood related industries, were discussed. (orig.)

Diauxic growth of Fibrobacter succinogenes S85 on cellobiose and lactose.

Science.gov (United States)

Ghali, Ines; Sofyan, Ahmad; Ohmori, Hideyuki; Shinkai, Takumi; Mitsumori, Makoto

2017-08-15

Fibrobacter succinogenes rapidly colonizes the preruminant calf rumen and becomes a dominant cellulolytic bacterium in the rumen after weaning. Although F. succinogenes actively degrades cellulose in the rumen, it seems that there is no or little of its substrate, cellulose, in the rumen of preweaned calves. We thus evaluated the ability of F. succinogenes to utilize lactose, a main sugar of milk, with or without the presence of cellobiose. We grew F. succinogenes S85 on media containing 2.5% lactose combined with 0%-0.2% cellobiose or a medium with 0.2% cellobiose but without lactose. The generation times on the 0.2% cellobiose medium and the 2.5% lactose medium were 1.9 and 16.2 h, respectively. The bacterium showed rapid growth on cellobiose and diauxic growth on the lactose media containing 0.05%-0.2% cellobiose. Moreover, the production of β-galactosidase was low in the presence of 0.1%-0.2% cellobiose. Since the β-galactosidase contained a signal peptide and a Por secretion system C-terminal sorting domain, we speculate that the β-galactosidase would be secreted from the bacterial cells by the Por secretion system. Our data indicate the possibility that F. succinogenes could colonize preruminant calf rumen, consuming the lactose present in cow milk. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Effect of lactic acid bacteria on the intestinal production of lactate and short-chain fatty acids, and the absorption of lactose

DEFF Research Database (Denmark)

Hove, H; Nordgaard-Andersen, I; Mortensen, P B

1994-01-01

(10) cells), but did not influence the concentrations and productions of DL-lactate and short-chain fatty acids in the ileostomic outputs and incubates. Large amounts of ingested lactic acid bacteria (4.2 x 10(10) cells) did not ameliorate lactose malabsorption measured by the breath-hydrogen test in 12...... lactose malabsorbers. This study shows that ingested lactic acid bacteria are indeed present in the colon, but it does not support the theory that they change the pattern of colonic fermentation or the degree of intestinal lactose malabsorption....

[Lactose intolerance].

Science.gov (United States)

Rosado, Jorge L

2016-09-01

The most common problem limiting milk consumption worldwide is lactose intolerance (LI), which is defined as the experience of gastrointestinal symptoms due to the intake of lactose-containing food. When symptoms ensue the intake of milk, the condition is referred as milk intolerance, and it may or may not be due to LI. The most common cause of LI is primary lactase deficiency which occurs in 30% of Mexican adults when one glass of milk is consumed (12-18 g of lactose). LI occurs in less than 15% of adults after the intake of this dose of lactose. Another cause of lactose intolerance is due to secondary lactase deficiency, which occurs because lactase is reduced due to diseases that affect the intestinal mucosa. Lactose intolerance can be eliminated or significantly reduced by elimination or reduction of the intake of milk and milk containing products. Recent studies demonstrate that when β-casein-A1 contained in milk is hydrolyzed it produces β-casomorphine-7 which is an opioid associated with milk intolerance.

Descriptive Sensory Analysis of Omashikwa, a traditional fermented ...

African Journals Online (AJOL)

UNAM002

2014-04-02

Apr 2, 2014 ... treatment of milk prior to fermentation and Hazard Analysis Critical ... spoilage microorganisms, reduce lactose intolerance to sensitive .... to good manufacturing practices on unit operations, particularly heat treatment on k-.

Lactose metabolism in Streptococcus lactis: studies with a mutant lacking glucokinase and mannose-phosphotransferase activities

International Nuclear Information System (INIS)

Thompson, J.; Chassy, B.M.; Egan, W.

1985-01-01

A mutant of Streptococcus lactis 133 has been isolated that lacks both glucokinase and phosphoenolpyruvate-dependent mannose- phosphotransferase (mannose-PTS) activities. The double mutant S. lactis 133 mannose-PTSd GK- is unable to utilize either exogenously supplied or intracellularly generated glucose for growth. Fluorographic analyses of metabolites formed during the metabolism of [ 14 C]lactose labeled specifically in the glucose or galactosyl moiety established that the cells were unable to phosphorylate intracellular glucose. However, cells of S. lactis 133 mannose-PTSd GK- readily metabolized intracellular glucose 6-phosphate, and the growth rates and cell yield of the mutant and parental strains on sucrose were the same. During growth on lactose, S. lactis 133 mannose-PTSd GK- fermented only the galactose moiety of the disaccharide, and 1 mol of glucose was generated per mol of lactose consumed. For an equivalent concentration of lactose, the cell yield of the mutant was 50% that of the wild type. The specific rate of lactose utilization by growing cells of S. lactis 133 mannose-PTSd GK- was ca. 50% greater than that of the wild type, but the cell doubling times were 70 and 47 min, respectively. High-resolution 31 P nuclear magnetic resonance studies of lactose transport by starved cells of S. lactis 133 and S. lactis 133 mannose-PTSd GK- showed that the latter cells contained elevated lactose-PTS activity. Throughout exponential growth on lactose, the mutant maintained an intracellular steady-state glucose concentration of 100 mM

Lactose metabolism in Streptococcus lactis: studies with a mutant lacking glucokinase and mannose-phosphotransferase activities

Energy Technology Data Exchange (ETDEWEB)

Thompson, J.; Chassy, B.M.; Egan, W.

1985-04-01

A mutant of Streptococcus lactis 133 has been isolated that lacks both glucokinase and phosphoenolpyruvate-dependent mannose- phosphotransferase (mannose-PTS) activities. The double mutant S. lactis 133 mannose-PTSd GK- is unable to utilize either exogenously supplied or intracellularly generated glucose for growth. Fluorographic analyses of metabolites formed during the metabolism of (/sup 14/C)lactose labeled specifically in the glucose or galactosyl moiety established that the cells were unable to phosphorylate intracellular glucose. However, cells of S. lactis 133 mannose-PTSd GK- readily metabolized intracellular glucose 6-phosphate, and the growth rates and cell yield of the mutant and parental strains on sucrose were the same. During growth on lactose, S. lactis 133 mannose-PTSd GK- fermented only the galactose moiety of the disaccharide, and 1 mol of glucose was generated per mol of lactose consumed. For an equivalent concentration of lactose, the cell yield of the mutant was 50% that of the wild type. The specific rate of lactose utilization by growing cells of S. lactis 133 mannose-PTSd GK- was ca. 50% greater than that of the wild type, but the cell doubling times were 70 and 47 min, respectively. High-resolution /sup 31/P nuclear magnetic resonance studies of lactose transport by starved cells of S. lactis 133 and S. lactis 133 mannose-PTSd GK- showed that the latter cells contained elevated lactose-PTS activity. Throughout exponential growth on lactose, the mutant maintained an intracellular steady-state glucose concentration of 100 mM.

Ethanol production from cellulose, lactose and xylose using yeasts and enzymes. Gewinnung von Ethanol aus Cellulose, Lactose, und Xylose mit Hilfe von Hefen und Enzymen

Energy Technology Data Exchange (ETDEWEB)

Schwank, U

1986-07-03

Experiments with mixtures of whey and corn showed that more than 85% of the lactose was degraded into ethanol. The applicability of cellulose was investigated by means of potatoes. Cellulase is inhibited by glucose, which is a fermentation intermediate, as well as by the end product ethanol. A cellulase inhibitor in potatoes was detected and stabilized; this inhibitor could be degraded into neutral components by a suitable enzyme. Saccharification and fermentation experiments showed that the cellulose fraction of potatoes can be reduced efficiently. The effects of non-enzymatic pretreatment on enzymatic degradation of cellulose, combined with fermentation of the degradation products, are illustrated by the example of cellulose treated with acid and alkaline substances. A continuous fermentation system was developed from which the ethanol is withdrawn in vapour form. The system made better use of the cellulase activity and increased the efficiency of a xylose-fermenting yeast. The new method is compared with batch experiments in order to assess its efficiency. The advantages of the continuous process are proved for two yeasts of the species Pachysolu and Pichia. Specific fermentation rates up to 0.08 g/(g x h) and fermentation yields up to 0.42 g ethanol/g xylose were achieved with Pichia stipitis.

The potential of species-specific tagatose-6-phosphate (T6P) pathway in Lactobacillus casei group for galactose reduction in fermented dairy foods.

Science.gov (United States)

Wu, Qinglong; Shah, Nagendra P

2017-04-01

Residual lactose and galactose in fermented dairy foods leads to several industrial and health concerns. There is very little information pertaining to manufacture of fermented dairy foods that are low in lactose and galactose. In the present study, comparative genomic survey demonstrated the constant presence of chromosome-encoded tagatose-6-phosphate (T6P) pathway in Lactobacillus casei group. Lactose/galactose utilization tests and β-galactosidase assay suggest that PTS Gal system, PTS Lac system and T6P pathway are major contributors for lactose/galactose catabolism in this group of organisms. In addition, it was found than lactose catabolism by Lb. casei group accumulated very limited galactose in the MRS-lactose medium and in reconstituted skim milk, whereas Streptococcus thermophilus and Lb. delbrueckii subsp. bulgaricus (Lb. bulgaricus) strains secreted high amount of galactose extracellularly. Moreover, co-culturing Lb. casei group with Str. thermophilus showed significant reduction in galactose content, while co-culturing Lb. casei group with Lb. bulgaricus showed significant reduction in lactose content but significant increase in galactose content in milk. Overall, the present study highlighted the potential of Lb. casei group for reducing galactose accumulation in fermented milks due to its species-specific T6P pathway. Copyright © 2016 Elsevier Ltd. All rights reserved.

Lactose Intolerance and Symptom Pattern of Lactose Intolerance among Healthy Volunteers.

Science.gov (United States)

Saha, Madhusudan; Parveen, Irin; Shil, Bimal Chandra; Saha, Shasanka Kumar; Banik, Ranjit Kumar; Majumder, Monojit; Salam, Mahjuba Umme; Islam, Asm Nazmul

2016-01-01

To see the prevalence of lactose intolerance (LI) and related symptoms following oral lactose challenge in healthy volunteers. Symptoms of abdominal pain, nausea, borborygmi, flatulence, and diarrhea were noted for 24 hours and blood glucose was estimated at 0 hour and 30 minutes after 25 gm oral lactose load to healthy volunteers. Failure to rise blood glucose level ≥ 1.1 mmol/l at 30 minutes after lactose intake from fasting level was taken as lactose malabsorption (LM), i.e., LI. A total of 166 volunteers (123 males, 43 females) with a mean age 34.78 ± 11.45 years participated in this study. Lactose intolerance was found among 85.54% (n = 142, M = 104, F = 38). The main symptoms of LI were diarrhea (n = 83, 58.4.0%), borborygmi (n = 81, 57.04%), abdominal pain (n = 35, 24.65%), and flatulence (n = 27, 19.0%). Lactose intolerance among healthy adults may be common in Bangladesh. Diarrhea and borborygmi were mostly associated symptoms of LI. Saha M, Parveen I, Shil BC, Saha SK, Banik RK, Majumder M, Salam MU, Nazmul Islam ASM. Lactose Intolerance and Symptom Pattern of Lactose Intolerance among Healthy Volunteers. Euroasian J Hepato-Gastroenterol 2016;6(1):5-7.

Production of ethanol and biomass starting to present lactose in the milk whey

International Nuclear Information System (INIS)

Angeles-Ramirez, K.; Arana-cuenca, A.; Tellez-Jurado, A.

2009-01-01

Milk whey is a by-product of the milk industry, a highly polluting waste due to the quantity of COD and BOD that it contains. The contamination caused by milk whey is mostly due to its lactose content. The fermentation of milk whey to ethanol is a possible road to reduce the polluting effect. (Author)

Temperature dependence of the multistability of lactose utilization network of Escherichia coli

Science.gov (United States)

Nepal, Sudip; Kumar, Pradeep

Biological systems are capable of producing multiple states out of a single set of inputs. Multistability acts like a biological switch that allows organisms to respond differently to different environmental conditions and hence plays an important role in adaptation to changing environment. One of the widely studied gene regulatory networks underlying the metabolism of bacteria is the lactose utilization network, which exhibits a multistable behavior as a function of lactose concentration. We have studied the effect of temperature on multistability of the lactose utilization network at various concentrations of thio-methylgalactoside (TMG), a synthetic lactose. We find that while the lactose utilization network exhibits a bistable behavior for temperature T >20° C , a graded response arises for temperature T lactose utilization network as a function of temperature and TMG concentration. Our results suggest that environmental conditions, in this case temperature, can alter the nature of cellular regulation of metabolism.

[Lactose malabsorption and -intolerance - who will benefit from a lactose-reduced diet?

Science.gov (United States)

Malham, Mikkel; Olin, Anne Bille; Pærregaard, Anders

2017-02-06

During the last decade, lactose-free diets have become increasingly popular in the general population, either isolated or as a part of a cow's milk-free diet. However, health-related benefits from a lactose-free diet are only documented for individuals with clinical lactose intolerance due to decreased intestinal lactase activity and subsequent lactose malabsorption. In this paper we summarize the current knowledge of lactose intolerance regarding diagnostic procedures and treatment.

The Lactose and Galactose Content of Cheese Suitable for Galactosaemia: New Analysis.

Science.gov (United States)

Portnoi, P A; MacDonald, A

2016-01-01

The UK Medical Advisory Panel of the Galactosaemia Support Group report the lactose and galactose content of 5 brands of mature Cheddar cheese, Comte and Emmi Emmental fondue mix from 32 cheese samples. The Medical Advisory Panel define suitable cheese in galactosaemia to have a lactose and galactose content consistently below 10 mg/100 g. A total of 32 samples (5 types of mature Cheddar cheese, Comte and "Emmi Swiss Fondue", an emmental fondue mix) were analysed by high-performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD) technology used to perform lactose and galactose analysis. Cheddar cheese types: Valley Spire West Country, Parkham, Lye Cross Vintage, Lye Cross Mature, Tesco West Country Farmhouse Extra Mature and Sainsbury's TTD West Country Farmhouse Extra Mature had a lactose and galactose content consistently below 10 mg/100 g (range <0.05 to 12.65 mg). All Comte samples had a lactose content below the lower limit of detection (<0.05 mg) with galactose content from <0.05 to 1.86 mg/100 g; all samples of Emmi Swiss Fondue had lactose below the lower limit of detection (<0.05 mg) and galactose between 2.19 and 3.04 mg/100 g. All of these cheese types were suitable for inclusion in a low galactose diet for galactosaemia. It is possible that the galactose content of cheese may change over time depending on its processing, fermentation time and packaging techniques.

Rapid discrimination of strain-dependent fermentation characteristics among Lactobacillus strains by NMR-based metabolomics of fermented vegetable juice.

Directory of Open Access Journals (Sweden)

Satoru Tomita

Full Text Available In this study, we investigated the applicability of NMR-based metabolomics to discriminate strain-dependent fermentation characteristics of lactic acid bacteria (LAB, which are important microorganisms for fermented food production. To evaluate the discrimination capability, six type strains of Lactobacillus species and six additional L. brevis strains were used focusing on i the difference between homo- and hetero-lactic fermentative species and ii strain-dependent characteristics within L. brevis. Based on the differences in the metabolite profiles of fermented vegetable juices, non-targeted principal component analysis (PCA clearly separated the samples into those inoculated with homo- and hetero-lactic fermentative species. The separation was primarily explained by the different levels of dominant metabolites (lactic acid, acetic acid, ethanol, and mannitol. Orthogonal partial least squares discrimination analysis, based on a regions-of-interest (ROIs approach, revealed the contribution of low-abundance metabolites: acetoin, phenyllactic acid, p-hydroxyphenyllactic acid, glycerophosphocholine, and succinic acid for homolactic fermentation; and ornithine, tyramine, and γ-aminobutyric acid (GABA for heterolactic fermentation. Furthermore, ROIs-based PCA of seven L. brevis strains separated their strain-dependent fermentation characteristics primarily based on their ability to utilize sucrose and citric acid, and convert glutamic acid and tyrosine into GABA and tyramine, respectively. In conclusion, NMR metabolomics successfully discriminated the fermentation characteristics of the tested strains and provided further information on metabolites responsible for these characteristics, which may impact the taste, aroma, and functional properties of fermented foods.

Effect of lactose on oro-cecal transit in lactose digesters and maldigesters

NARCIS (Netherlands)

He, T.; Priebe, M. G.; Welling, G. W.; Vonk, R. J.

2006-01-01

Background The transit time of the small intestine, in addition to lactase activity, may influence lactose digestion and thus play a role in the occurrence of lactose intolerance. The objectives of this study were to investigate the effect of lactose on the oro-cecal transit time (OCTT) in lactose

Lactose Intolerance (For Kids)

Science.gov (United States)

... Staying Safe Videos for Educators Search English Español Lactose Intolerance KidsHealth / For Kids / Lactose Intolerance What's in this ... LAK-tose in-TAHL-er-ents). What Is Lactose Intolerance? People who have lactose intolerance have trouble digesting ( ...

Lactose Intolerance (For Teens)

Science.gov (United States)

... Staying Safe Videos for Educators Search English Español Lactose Intolerance KidsHealth / For Teens / Lactose Intolerance What's in this ... t really consider it a disease. Who Gets Lactose Intolerance? A person may be or may become lactose ...

Selective and sensitive determination of lactose in low-lactose dairy products with HPAEC-PAD.

Science.gov (United States)

van Scheppingen, Wibo B; van Hilten, Piet H; Vijverberg, Marieke P; Duchateau, Alexander L L

2017-08-15

The demand for low lactose dairy products is increasing and more different lactose free food is commercially available. The level of lactose in these products decreased during the last years and nowadays a concentration of lactose free". For the determination of the lactose concentrations in these dairy products a sensitive analysis method is needed. We developed a method for the determination of low concentrations of lactose in a wide range of dairy products. A simple sample preparation with dilution, centrifugation and ultrafiltration is efficient for the isolation of lactose from the sample matrix. In this paper, a new HPAEC-PAD analysis on a CarboPac PA100 column gives a good separation of lactose from the other saccharides. This separation in combination with the PAD detector yields a selective and sensitive method for the quantification at the desired concentrations of lactose in low lactose dairy products. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

An enzymic method for the determination of [1-14C] lactose

International Nuclear Information System (INIS)

Davies, E.; Bourke, E.; Costello, J.

1975-01-01

A simple, rapid and specific method for the determination of [1- 14 C] lactose in biological fluids is described. It is based on the enzymic removal of the 1- 14 C atom of lactose as [ 14 C] carbon dioxide, using commercially available enzymes. The assay involves only one critical addition and the entire reaction can be carried out in a scintillation vial. (author)

Characterization of a lactose-responsive promoter of ATP-binding cassette (ABC) transporter gene from Lactobacillus acidophilus 05-172.

Science.gov (United States)

Zeng, Zhu; Zuo, Fanglei; Yu, Rui; Zhang, Bo; Ma, Huiqin; Chen, Shangwu

2017-09-01

A novel lactose-responsive promoter of the ATP-binding cassette (ABC) transporter gene Lba1680 of Lactobacillus acidophilus strain 05-172 isolated from a traditionally fermented dairy product koumiss was characterized. In L. acidophilus 05-172, expression of Lba1680 was induced by lactose, with lactose-induced transcription of Lba1680 being 6.1-fold higher than that induced by glucose. This is in contrast to L. acidophilus NCFM, a strain isolated from human feces, in which expression of Lba1680 and Lba1679 is induced by glucose. Both gene expression and enzyme activity assays in L. paracasei transformed with a vector containing the inducible Lba1680 promoter (PLba1680) of strain 05-172 and a heme-dependent catalase gene as reporter confirmed that PLba1680 is specifically induced by lactose. Its regulatory expression could not be repressed by glucose, and was independent of cAMP receptor protein. This lactose-responsive promoter might be used in the expression of functional genes in L. paracasei incorporated into a lactose-rich environment, such as dairy products. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Rapid and efficient galactose fermentation by engineered Saccharomyces cerevisiae.

Science.gov (United States)

Quarterman, Josh; Skerker, Jeffrey M; Feng, Xueyang; Liu, Ian Y; Zhao, Huimin; Arkin, Adam P; Jin, Yong-Su

2016-07-10

In the important industrial yeast Saccharomyces cerevisiae, galactose metabolism requires energy production by respiration; therefore, this yeast cannot metabolize galactose under strict anaerobic conditions. While the respiratory dependence of galactose metabolism provides benefits in terms of cell growth and population stability, it is not advantageous for producing fuels and chemicals since a substantial fraction of consumed galactose is converted to carbon dioxide. In order to force S. cerevisiae to use galactose without respiration, a subunit (COX9) of a respiratory enzyme was deleted, but the resulting deletion mutant (Δcox9) was impaired in terms of galactose assimilation. Interestingly, after serial sub-cultures on galactose, the mutant evolved rapidly and was able to use galactose via fermentation only. The evolved strain (JQ-G1) produced ethanol from galactose with a 94% increase in yield and 6.9-fold improvement in specific productivity as compared to the wild-type strain. (13)C-metabolic flux analysis demonstrated a three-fold reduction in carbon flux through the TCA cycle of the evolved mutant with redirection of flux toward the fermentation pathway. Genome sequencing of the JQ-G1 strain revealed a loss of function mutation in a master negative regulator of the Leloir pathway (Gal80p). The mutation (Glu348*) in Gal80p was found to act synergistically with deletion of COX9 for efficient galactose fermentation, and thus the double deletion mutant Δcox9Δgal80 produced ethanol 2.4 times faster and with 35% higher yield than a single knockout mutant with deletion of GAL80 alone. When we introduced a functional COX9 cassette back into the JQ-G1 strain, the JQ-G1-COX9 strain showed a 33% reduction in specific galactose uptake rate and a 49% reduction in specific ethanol production rate as compared to JQ-G1. The wild-type strain was also subjected to serial sub-cultures on galactose but we failed to isolate a mutant capable of utilizing galactose without

Severe lactose intolerance with lactosuria and vomiting.

Science.gov (United States)

Hosková, A; Sabacký, J; Mrskos, A; Pospísil, R

1980-01-01

An infant with lactose intolerance is described. A breast-fed infant developed vomiting at 3 weeks, and became dehydrated. Lactosuria, aminoaciduria, and liver damage were preesent. A milk-free diet led to rapid recovery. At 6 months a normal diet was well tolerated. PMID:7416780

Identification of lactose phosphotransferase systems in Lactobacillus gasseri ATCC 33323 required for lactose utilization.

Science.gov (United States)

Francl, Alyssa L; Hoeflinger, Jennifer L; Miller, Michael J

2012-04-01

Improving the annotation of sugar catabolism-related genes requires functional characterization. Our objective was to identify the genes necessary for lactose utilization by Lactobacillus gasseri ATCC 33323 (NCK334). The mechanism of lactose transport in many lactobacilli is a lactose/galactose-specific permease, yet no orthologue was found in NCK334. Characterization of an EI knockout strain [EI (enzyme I) is required for phosphotransferase system transporter (PTS) function] demonstrated that L. gasseri requires PTS(s) to utilize lactose. In order to determine which PTS(s) were necessary for lactose utilization, we compared transcript expression profiles in response to lactose for the 15 complete PTSs identified in the NCK334 genome. PTS 6CB (LGAS_343) and PTS 8C (LGAS_497) were induced in the presence of lactose 107- and 53-fold, respectively. However, L. gasseri ATCC 33323 PTS 6CB, PTS 8C had a growth rate similar to that of the wild-type on semisynthetic deMan, Rogosa, Sharpe (MRS) medium with lactose. Expression profiles of L. gasseri ATCC 33323 PTS 6CB, PTS 8C in response to lactose identified PTS 9BC (LGAS_501) as 373-fold induced, whereas PTS 9BC was not induced in NCK334. Elimination of growth on lactose required the inactivation of both PTS 6CB and PTS 9BC. Among the six candidate phospho-β-galactosidase genes present in the NCK334 genome, LGAS_344 was found to be induced 156-fold in the presence of lactose. In conclusion, we have determined that: (1) NCK334 uses a PTS to import lactose; (2) PTS 6CB and PTS 8C gene expression is strongly induced by lactose; and (3) elimination of PTS 6CB and PTS 9BC is required to prevent growth on lactose.

Growth-Phase Sterigmatocystin Formation on Lactose Is Mediated via Low Specific Growth Rates in Aspergillus nidulans

Directory of Open Access Journals (Sweden)

Zoltán Németh

2016-11-01

Full Text Available Seed contamination with polyketide mycotoxins such as sterigmatocystin (ST produced by Aspergilli is a worldwide issue. The ST biosynthetic pathway is well-characterized in A. nidulans, but regulatory aspects related to the carbon source are still enigmatic. This is particularly true for lactose, inasmuch as some ST production mutant strains still synthesize ST on lactose but not on other carbon substrates. Here, kinetic data revealed that on d-glucose, ST forms only after the sugar is depleted from the medium, while on lactose, ST appears when most of the carbon source is still available. Biomass-specified ST production on lactose was significantly higher than on d-glucose, suggesting that ST formation may either be mediated by a carbon catabolite regulatory mechanism, or induced by low specific growth rates attainable on lactose. These hypotheses were tested by d-glucose limited chemostat-type continuous fermentations. No ST formed at a high growth rate, while a low growth rate led to the formation of 0.4 mg·L−1 ST. Similar results were obtained with a CreA mutant strain. We concluded that low specific growth rates may be the primary cause of mid-growth ST formation on lactose in A. nidulans, and that carbon utilization rates likely play a general regulatory role during biosynthesis.

Characterization of typical Tunisian fermented milk, rayeb | Samet ...

African Journals Online (AJOL)

Traditional Tunisian fermented milk, rayeb, was produced according to the traditional method. Physicochemical, microstructural, microbiological characteristics and major aromatic compounds evaluation were studied. The results show a decrease in lactose content and pH value and an increase in lactic acid during ...

Enzymic lactose hydrolysis

Energy Technology Data Exchange (ETDEWEB)

Miller, J J; Brand, J C

1980-01-01

Acid or enzymic hydrolysis can be used to hydrolyze lactose. Advantages of both are compared and details of enzymic hydrolysis using yeast or fungal enzymes given. The new scheme outlined involves recycling lactase. Because lactose and lactase react to ultrafiltration (UF) membranes differently separation is possible. Milk or milk products are ultrafiltered to separate a concentrate from a lactose-rich permeate which is treated with lactase in a reactor until hydrolysis reaches a required level. The lactase can be removed by UF as it does not permeate the membrane, and it is recycled back to the reactor. Permeate from the second UF stage may or may not be recombined with the concentrate from the first stage to produce a low lactose product (analysis of a typical low-lactose dried whole milk is given). Batch or continuous processes are explained and a batch process without enzyme recovery is discussed. (Refs. 4).

Improved clinical tolerance to chronic lactose ingestion in subjects with lactose intolerance: a placebo effect?

Science.gov (United States)

Briet, F; Pochart, P; Marteau, P; Flourie, B; Arrigoni, E; Rambaud, J

1997-01-01

Background—Uncontrolled studies of lactose intolerant subjects have shown that symptom severity decreases after chronic lactose consumption. Adaptation of the colonic flora might explain this improvement. 
Aims—To compare the effects of regular administration of either lactose or sucrose on clinical tolerance and bacterial adaptation to lactose. 
Methods—Forty six lactose intolerant subjects underwent two 50 g lactose challenges on days 1 and 15. Between these days they were given 34 g of lactose or sucrose per day, in a double blind protocol. Stool samples were obtained on days 0 and 14, to measure faecal β-galactosidase and pH. Symptoms, breath H2 excretion, faecal weight and electrolytes, and orofaecal transit time were assessed. 
Results—Except for faecal weight, symptoms were significantly milder during the second challenge in both groups, and covariance analysis showed no statistical difference between them. In the lactose group, but not in the sucrose group, faecal β-galactosidase activity increased, pH dropped, and breath H2 excretion decreased. 
Conclusion—Bacterial adaptation occurred when lactose intolerant subjects ingested lactose for 13 days, and all symptoms except diarrhoea regressed. Clinical improvement was also observed in the control group which displayed no signs of metabolic adaptation. This suggests that improved clinical tolerance may be just a placebo effect. 

 Keywords: lactose; lactose intolerance; colonic adaptation; lactase deficiency PMID:9414969

Lactose Intolerance (For Parents)

Science.gov (United States)

... to the diet. If you think that your child has a lactose intolerance, call your doctor. Who Gets Lactose Intolerance? Lactose intolerance is more common among people of Asian, African, Native American, and Hispanic descent. For most people ...

Donkey Milk for Manufacture of Novel Functional Fermented Beverages.

Science.gov (United States)

Perna, Annamaria; Intaglietta, Immacolata; Simonetti, Amalia; Gambacorta, Emilio

2015-06-01

The aim of this work was to investigate on the functional features of a donkey milk probiotic berevage as a novel food. Particularly, it was to study the decrease of lactose content and the antioxidant activity of standard yogurt (YC) and probiotic yogurt (YP; Lactobacillus acidophilus, Lactobacillus casei) from donkey milk during the storage up to 30 d at 4 ºC. The evolution of lactose content using enzymatic-spectrophotometric kits was analyzed. Antioxidant activity of yogurt was measured using 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS), ferric reducing antioxidant power (FRAP), and thiol assays. Parallel consumer sensory studies were carried out as consumer test in order to gain information about the impact of these novel fermented beverages on sensory perceptions. The statistical analysis has shown significant effect of studied factors. The results showed that the lactose content gradually decreased during storage in both yogurts, reaching values of 2.36% and 2.10% in YC and YP, respectively, at 30 d (P yogurt types, the antioxidant activity increased, but YP showed a higher antioxidant activity than YC. The results suggest that the antioxidant activity of yogurt samples was affected by cultures of lactic acid bacteria (LAB). We conclude that the fermented donkey milk could be configured as health and nutraceutical food, which aims to meet nutritional requirements of certain consumers groups with lactose or cow milk protein intolerance. © 2015 Institute of Food Technologists®

Alcohol production by selected yeast strains in lactase-hydrolyzed acid whey

Energy Technology Data Exchange (ETDEWEB)

O' Leary, V S; Green, R; Sullivan, B C; Holsinger, V H

1977-07-01

Ethanol production by Kluyveromyces fragilis and Saccharomyces cerevisiae was studied using cottage cheese whey in which 80 to 90 percent of the lactose present had been prehydrolyzed to glucose and galactose. Complete fermentation of the sugar by K. fragilis required 120 hr at 30/sup 0/C in lactase-hydrolyzed whey compared to 72 hr in nonhydrolyzed whey. This effect was due to a diauxic fermentation pattern in lactase-hydrolyzed whey with glucose being fermented before galactose. Ethanol yields of about 2 percent were obtained in both types of whey when K. fragilis was the organism used for fermentation. Saccharomyces cerevisiae produced alcohol from glucose more rapidly than K. fragilis, but galactose was fermented only when S. cerevisiae was pregrown on galactose. Slightly lower alcohol yields were obtained with S. cerevisiae, owing to the presence of some lactose in the whey which was not fermented by this organism. Although prehydrolysis of lactose in whey and whey fractions is advantageous in that microbial species unable to ferment lactose may be utilized, diauxic and galactose utilization problems must be considered.

Undernourished Children and Milk Lactose.

Science.gov (United States)

Grenov, Benedikte; Briend, André; Sangild, Per T; Thymann, Thomas; Rytter, Maren H; Hother, Anne-Louise; Mølgaard, Christian; Michaelsen, Kim F

2016-03-01

Lactose is an important energy source in young mammals, and in fully breast-fed human infants, it constitutes around 40% of the total daily energy intake. The role of lactose in feeding of undernourished infants and young children is not well described. A narrative review of the potential positive and negative effects of lactose in the treatment of undernourished children. Searches were conducted using PUBMED and Web of Science up to July 2015. Relevant references in the retrieved articles were included. Lactose may exhibit several health benefits in young children, including a prebiotic effect on the gut microbiota and a positive effect on mineral absorption. Studies in piglets suggest there might also be a stimulating effect on growth, relative to other carbohydrates. Lactose intolerance is a potential concern for undernourished children. Most undernourished children seem to tolerate the currently recommended (low lactose level) therapeutic foods well. However, a subgroup of severely undernourished children with secondary lactase deficiency due to severe diarrhea or severe enteropathy may benefit from products with even more restricted lactose content. At limited extra costs, lactose or lactose-containing milk ingredients may have beneficial effects if added to food products for undernourished children. Lactose may be an overlooked beneficial nutrient for young and undernourished children. Research is needed to define the balance between beneficial and detrimental effects of lactose in undernourished children at different ages and with different degrees of diarrhea and intestinal integrity. © The Author(s) 2016.

Quantitative determination of micronization-induced changes in the solid state of lactose.

Science.gov (United States)

Della Bella, A; Müller, M; Soldati, L; Elviri, L; Bettini, R

2016-05-30

Lactose, in particular α-lactose monohydrate, is the most used carrier for inhalation. Its surface and solid-state properties play a key role in determining Dry Powder Inhalers (DPIs) performance. Techniques such as X-Ray Powder Diffraction (XRPD) and Differential Scanning Calorimetry (DSC), which are commonly used for the characterization of lactose, are not always capable of explaining the solid-state changes induced by processing, such as micronization. In the present work, the evaluation of the effect of the micronization process on the solid-state properties of lactose was carried out by XRPD and DSC and a satisfactory, although not unequivocal, interpretation of the thermal behaviour of lactose was obtained. Thus, a new gravimetric method correlating in a quantitative manner the weight change in specific sections of the Dynamic Vapour Sorption (DVS) profile and the amount of different forms of α-lactose (hygroscopic anhydrous, stable anhydrous and amorphous) simultaneously present in a given sample was developed and validated. The method is very simple and provides acceptable accuracy in phase quantitation (LOD=1.6, 2.4 and 2.7%, LOQ=5.4, 8.0 and 8.9% for hygroscopic anhydrous, stable anhydrous and amorphous α-lactose, respectively). The application of this method to a sample of micronized lactose led to results in agreement with those obtained by DSC and evidenced that hygroscopic anhydrous α-lactose, rather than amorphous lactose, can be generated in the micronization process. The proposed method may find a more general application for the quantification of polymorphs of compounds different than lactose, provided that the various solid phases afford different weight variations in specific regions of the DVS profile. Copyright © 2016 Elsevier B.V. All rights reserved.

Lactose tolerance tests

Science.gov (United States)

Hydrogen breath test for lactose tolerance ... Two common methods include: Lactose tolerance blood test Hydrogen breath test The hydrogen breath test is the preferred method. It measures the amount of hydrogen ...

Lactose intolerance and other disaccharidase deficiency.

Science.gov (United States)

Tomar, Balvir S

2014-09-01

Intolerance to foods which contain lactose can cause a range of intestinal and systemic symptoms. These symptoms are caused by Lactase deficiency which is encoded by a single gene (LCT) of ≈ 50 kb located on chromosome 2q21. In some food items, lactose has been missed because of "hidden" lactose due to inadequately labeled, confusing diagnosis of lactose intolerance based on dietary restriction of dairy foods. Two polymorphisms, C/T13910 and G/A22018, linked to hypolactasia, correlate with breath hydrogen and symptoms after lactose. The key in the management of lactose intolerance is the dietary removal of lactose. Patients diagnosed as lactose intolerant must be advised of "risk" foods, inadequately labeled, including processed meats, bread, cake mixes, soft drinks, and lagers. This review highlights the types, symptoms and management of lactose intolerance and also highlights differences from milk allergy which closely mimics the symptoms of lactose intolerance.

Fermentative conversion of swine and poultry wastes into nitrogen-enriched feedstuff for ruminants

Energy Technology Data Exchange (ETDEWEB)

Reddy, C A; Erdman, M D

1979-01-01

Swine and poultry wastes, augmented with carbohydrate-rich agroindustrial residues, were fermentatively converted into N-enriched feeds for ruminants. There was little increase in total N (TN) when unsupplemented swine waste filtrate (SWF) was fermented at pH 5.5, but considerable increase in TN was observed during fermentation of carbohydrate-supplemented SWF. The crude protein (CP) of the products ranged from 26-39%. Supplementation with cheese whey powder (CWP), potato starch, corn starch, or corn molasses gave 48, 33, 72, and 28% increases in TN respectively. Fermentation of CWP-supplemented SWF at pH 7.0 resulted in approximately 90% utilization of the added lactose within 8 hours and the product has a CP content of 47%. Fermentation of unsupplemented poultry waste filtrate (PWF) resulted in little increase in TN, while ammonia-N (AN) increased 5.5-fold and contributed 50% of the CP in the product obtained at the end of 8 hours of fermentation. In CWP-supplemented PWF fermentation 92% of the added whey lactose was metabolized, TN increased by 35%, and AN accounted for 63% of the TN. Thus, ammoniated fermentation of individual or mixed animal wastes, supplemented with a carbohydrate-rich agricultural residue can be conducted efficiently, batchwise, at pH 7.0 and 43 degrees, by indigenous microbial flora in the respective waste. The products obtained in each case are enriched in CP and organic acids.

21 CFR 168.122 - Lactose.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Lactose. 168.122 Section 168.122 Food and Drugs... § 168.122 Lactose. (a) Lactose is the carbohydrate normally obtained from whey. It may be anhydrous or... the following specifications: (1) The lactose content is not less than 98.0 percent, mass over mass (m...

Acetate production from whey lactose using co-immobilized cells of homolactic and homoacetic bacteria in a fibrous-bed bioreactor

Energy Technology Data Exchange (ETDEWEB)

Huang, Y.; Yang, S.T. [Ohio State Univ., Columbus, OH (United States). Dept. of Chemical Engineering

1998-11-20

Acetate was produced from whey lactose in batch and fed-batch fermentations using co-immobilized cells of Clostridium formicoaceticum and Lactococcus lactis. The cells were immobilized in a spirally wound fibrous sheet packed in a 0.45-L column reactor, with liquid circulated through a 5-L stirred-tank fermentor. Industrial-grade nitrogen sources, including corn steep liquor, casein hydrolysate, and yeast hydrolysate, were studied as inexpensive nutrient supplements to whey permeate and acid whey. Supplementation with either 2.5% (v/v) corn steep liquor or 1.5 g/L casein hydrolysate was adequate for the cocultured fermentation. The overall acetic acid yield from lactose was 0.9 g/g, and the productivity was 0.25 g/(L h). Both lactate and acetate at high concentrations inhibited the homoacetic fermentation. To overcome these inhibitions, fed-batch fermentations were used to keep lactate concentration low and to adapt cells to high-concentration acetate. The final acetate concentration obtained in the fed-batch fermentations were used to keep lactate concentration low and to adapt cells to high-concentration acetate. The final acetate concentration obtained in the fed-batch fermentation was 75 g/L, which was the highest acetate concentration ever produced by C. formicoaceticum. Even at this high acetate concentration, the overall productivity was 0.18 g/(L h) based on the total medium volume and 1.23 g/(L h) based on the fibrous-bed reactor volume. The cells isolated from the fibrous-bed bioreactor at the end of this study were more tolerant to acetic acid than the original culture used to seed the bioreactor, indicating that adaptation and natural selection of acetate-tolerant strains occurred. This cocultured fermentation process could be used to produce a low-cost acetate deicer from whey permeate and acid whey.

Effects of partial replacement of corn grain with lactose in calf starters on ruminal fermentation and growth performance.

Science.gov (United States)

Saegusa, A; Inouchi, K; Ueno, M; Inabu, Y; Koike, S; Sugino, T; Oba, M

2017-08-01

The objective of this study was to evaluate effects of partial replacement of dry ground corn with lactose in calf starters on dry matter intake, growth rate, ruminal pH, and volatile fatty acid profile. Sixty Holstein bull calves were raised on a high plane of nutrition program until 55 d of age. Calves were fed texturized calf starters containing 30.1% steam-flaked grains and lactose at 0 (control), 5, or 10% (n = 20 for each treatment) on a dry matter basis. All calves were fed treatment calf starters ad libitum from d 7 and kleingrass hay from d 35. Ruminal pH was measured continuously immediately after weaning (d 55-62) for 15 calves (n = 5 per treatment), and 3 wk after weaning (d 77 to 80) for the other 45 calves (n = 15 per treatment). Dry matter intake, growth performance, and ruminal pH variables were not affected by treatment. However, according to Spearman's correlation coefficient (r s ) analyses, lactose intake was positively correlated with dairy minimum ruminal pH (r s = 0.306) for the data collected from d 77 to 80. Similarly, hay intake was not affected by treatment, but positively correlated with daily mean (r s = 0.338) and maximum ruminal pH (r s = 0.408) and negatively correlated with duration pH lactose than control (35.3 vs. 40.2%) for ruminal fluid collected on d 80; however, molar ratio of butyrate was not affected by treatment. These results indicate that lactose inclusion in calf starters up to 10% of dry matter might not affect dry matter intake and growth performance of calves, but that greater lactose and hay intake might be associated with higher ruminal pH. The Authors. Published by the Federation of Animal Science Societies and Elsevier Inc. on behalf of the American Dairy Science Association®. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/3.0/).

[Pharmaceutical drugs containing lactose can as a rule be used by persons with lactose intolerance].

Science.gov (United States)

Vinther, Siri; Rumessen, Jöri Johannes; Christensen, Mikkel

2015-03-09

Lactose is often used as an excipient in pharmaceutical drugs. Current evidence indicates that the amount of lactose in most drugs is not sufficient to cause symptoms in persons with lactose intolerance, although interindividual differences in sensitivity probably exist. Patient preferences and/or suboptimal treatment adherence could be reasons for considering lactose-free drug alternatives.

A mechanistic investigation on the utilization of lactose as a protective agent for multi-unit pellet systems.

Science.gov (United States)

Chin, Wun Chyi; Chan, Lai Wah; Heng, Paul Wan Sia

2016-03-01

The effect of lactose particle size on the extent of pellet coat damage was investigated. The extent of pellet coat damage increased linearly with lactose median particle size. It was observed that coated pellets compressed with coarser lactose grades had larger and deeper surface indentations. The surfaces of the pellets compressed with coarser lactose grades were also found to be significantly rougher. Micronized lactose was capable of protecting pellet coats from damage brought about by the presence of coarser lactose particles. The findings suggested a protective effect that micronized lactose conferred to pellet coats was not only through dimensional delimitations but also by higher interparticulate friction and longer particle rearrangement phase. As a result, the pellet volume fraction in the system was reduced. The extent of pellet coat damage was found to escalate when the pellet volume fraction in such system increased beyond a critical value of 0.39.

Effect of mixing during fermentation in yogurt manufacturing.

Science.gov (United States)

Aguirre-Ezkauriatza, E J; Galarza-González, M G; Uribe-Bujanda, A I; Ríos-Licea, M; López-Pacheco, F; Hernández-Brenes, C M; Alvarez, M M

2008-12-01

In traditional yogurt manufacturing, the yogurt is not agitated during fermentation. However, stirring could be beneficial, particularly for improving heat and mass transport across the fermentation tank. In this contribution, we studied the effect of low-speed agitation during fermentation on process time, acidity profile, and microbial dynamics during yogurt fermentation in 2 laboratory-scale fermenters (3 and 5 L) with different heat-transfer characteristics. Lactobacillus bulgaricus and Streptococcus thermophilus were used as fermenting bacteria. Curves of pH, lactic acid concentration, lactose concentration, and bacterial population profiles during fermentation are presented for static and low-agitation conditions during fermentation. At low-inoculum conditions, agitation reduced the processing time by shortening the lag phase. However, mixing did not modify the duration or the shape of the pH profiles during the exponential phase. In fermentors with poor heat-transfer characteristics, important differences in microbial dynamics were observed between the agitated and nonagitated fermentation experiments; that is, agitation significantly increased the observable specific growth rate and the final microbial count of L. bulgaricus.

Fermentation capability of bulk milk under usual conditions

OpenAIRE

BOUŠKOVÁ, Lucie

2012-01-01

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

A Novel Millet-Based Probiotic Fermented Food for the Developing World

Directory of Open Access Journals (Sweden)

Elisa Di Stefano

2017-05-01

Full Text Available Probiotic yogurt, comprised of a Fiti sachet containing Lactobacillus rhamnosus GR-1 and Streptococcus thermophilus C106, has been used in the developing world, notably Africa, to alleviate malnutrition and disease. In sub-Saharan African countries, fermentation of cereals such as millet, is culturally significant. The aim of this study was to investigate the fermentation capability of millet when one gram of the Fiti sachet consortium was added. An increase of 1.8 and 1.4 log CFU/mL was observed for S. thermophilus C106 and L. rhamnosus GR-1 when grown in 8% millet in water. Single cultures of L. rhamnosus GR-1 showed the highest μmax when grown in the presence of dextrose, galactose and fructose. Single cultures of S. thermophilus C106 showed the highest μmax when grown in the presence of sucrose and lactose. All tested recipes reached viable counts of the probiotic bacteria, with counts greater than 106 colony-forming units (CFU/mL. Notably, a number of organic acids were quantified, in particular phytic acid, which was shown to decrease when fermentation time increased, thereby improving the bioavailability of specific micronutrients. Millet fermented in milk proved to be the most favorable, according to a sensory evaluation. In conclusion, this study has shown that sachets being provided to African communities to produce fermented milk, can also be used to produce fermented millet. This provides an option for when milk supplies are short, or if communities wish to utilize the nutrient-rich qualities of locally-grown millet.

Decrease in TSH levels after lactose restriction in Hashimoto's thyroiditis patients with lactose intolerance.

Science.gov (United States)

Asik, Mehmet; Gunes, Fahri; Binnetoglu, Emine; Eroglu, Mustafa; Bozkurt, Neslihan; Sen, Hacer; Akbal, Erdem; Bakar, Coskum; Beyazit, Yavuz; Ukinc, Kubilay

2014-06-01

We aimed to evaluate the prevalence of lactose intolerance (LI) in patients with Hashimoto's thyroiditis(HT) and the effects of lactose restriction on thyroid function in these patients. Eighty-three HT patients taking L-thyroxine (LT4) were enrolled, and lactose tolerance tests were performed on all patients. Lactose intolerance was diagnosed in 75.9 % of the patients with HT. Thirty-eight patients with LI were started on a lactose-restricted diet for 8 weeks. Thirty-eight patients with LI (30 euthyroid and 8 with subclinical hypothyroidism), and 12 patients without LI were included in the final analysis. The level of TSH significantly decreased in the euthyroid and subclinical hypothyroid patients with LI [from 2.06 ± 1.02 to 1.51 ±1.1 IU/mL and from 5.45 ± 0.74 to 2.25 ± 1.88 IU/mL,respectively (both P0.05). Lactose intolerance occurs at a high frequency in HT patients. Lactose restriction leads to decreased levels of TSH, and LI should be considered in hypothyroid patients who require increasing LT4 doses,have irregular TSH levels and are resistant to LT4 treatment.

Real-Time Monitoring of Chemical Changes in Three Kinds of Fermented Milk Products during Fermentation Using Quantitative Difference Nuclear Magnetic Resonance Spectroscopy.

Science.gov (United States)

Lu, Yi; Ishikawa, Hiroto; Kwon, Yeondae; Hu, Fangyu; Miyakawa, Takuya; Tanokura, Masaru

2018-02-14

Fermented milk products are rising in popularity throughout the world as a result of their health benefits, including improving digestion, normalizing the function of the immune system, and aiding in weight management. This study applies an in situ quantitative nuclear magnetic resonance method to monitor chemical changes in three kinds of fermented milk products, Bulgarian yogurt, Caspian Sea yogurt, and kefir, during fermentation. As a result, the concentration changes in nine organic compounds, α/β-lactose, α/β-galactose, lactic acid, citrate, ethanol, lecithin, and creatine, were monitored in real time. This revealed three distinct metabolic processes in the three fermented milk products. Moreover, pH changes were also determined by variations in the chemical shift of citric acid during the fermentation processes. These results can be applied to estimate microbial metabolism in various flora and help guide the fermentation and storage of various fermented milk products to improve their quality, which may directly influence human health.

Water-lactose behavior as a function of concentration and presence of lactic acid in lactose model systems.

Science.gov (United States)

Wijayasinghe, Rangani; Vasiljevic, Todor; Chandrapala, Jayani

2015-12-01

The presence of high amounts of lactic acid in acid whey restricts its ability to be further processed because lactose appears to remain in its amorphous form. A systematic study is lacking in this regard especially during the concentration step. Hence, the main aim of the study was to establish the structure and behavior of water molecules surrounding lactose in the presence of 1% (wt/wt) lactic acid at a concentration up to 50% (wt/wt). Furthermore, the crystallization nature of freeze-dried lactose with or without lactic acid was established using differential scanning calorimetry and Fourier transform infrared spectroscopy. Two mechanisms were proposed to describe the behavior of water molecules around lactose molecules during the concentration of pure lactose and lactose solutions with lactic acid. Pure lactose solution exhibited a water evaporation enthalpy of ~679 J·g(-1), whereas lactose+ lactic acid solution resulted in ~965 J·g(-1) at a 50% (wt/wt) concentration. This indicates a greater energy requirement for water removal around lactose in the presence of lactic acid. Higher crystallization temperatures were observed with the presence of lactic acid, indicating a delay in crystallization. Furthermore, less crystalline lactose (~12%) was obtained in the presence of lactic acid, indicating high amorphous nature compared with pure lactose where ~50% crystallinity was obtained. The Fourier transform infrared spectra revealed that the strong hydration layer consisting lactic acid and H3O(+) ions surrounded lactose molecules via strong H bonds, which restricted water mobility, induced a change in structure of lactose, or both, creating unfavorable conditions for lactose crystallization. Thus, partial or complete removal of lactic acid from acid whey may be the first step toward improving the ability of acid whey to be processed. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Surface area of lactose and lactose granulates on consolidation and compaction

NARCIS (Netherlands)

Riepma, Klaas Alouis

1993-01-01

This dissertation discusses the effect of short time storage at different conditions on the strength and the specific BET surface area of lactose tablets. In addition, some aspects are studied of the consolidation and compaction properties of crystalline lactose fractions in heterogeneous systems.

Lactose Intolerance and the Irritable Colon

OpenAIRE

McSherry, J. A.

1982-01-01

Symptoms of lactase deficiency include nausea, abdominal pain, distension, bloating and diarrhea after ingesting foods which contain lactose. Lactose intolerance and bowel motility disorders have similar symptoms, and people with irritable bowel syndrome and unexplained abdominal pain may have lactose intolerance. A definite diagnosis can be made by detecting hydrogen in the breath after a lactose load, by lactase assay from a small bowel biopsy specimen or by lactose intolerance testing. Lac...

Production, characteristics and fermentation of soymilk

Directory of Open Access Journals (Sweden)

Rajka Božanić

2006-12-01

Full Text Available Interest for soybean increases because of its extraordinary nutritive and health characteristics. In West countries soymilk is intended for population that cannot consume cow’s milk, due to lactose intolerance, allergies to cow’s milk proteins or non consumption of animal foodstuffs from belief. Health benefits of soymilk increase significantly by fermentation with lactic acid bacteria. Because of that, in this paper composition of soybean is described, with special overview on proteins, lipids, and carbohydrates as well as antinutritive factors and isoflavones. Soymilk composition and production, and its nutritive value are represented also. Advantages of fermentation of soybean and soymilk are described, especially with probiotic lactic acid bacteria.

Optimisation of minimal media for production of aroma compounds typical for fermented milk products

Directory of Open Access Journals (Sweden)

Nevenka Mazić

2008-08-01

Full Text Available The aim of this research was to optimize the composition of minimalgrowth media containing lactose and milk, in which lactic acid bacteria (LAB would produce the maximum amount of volatile aroma compounds typical for fermented milk products. Ingredients used for the preparation of media were casein, tri-sodium-citrate, lactose, milk minerals, whey proteins and milk with 1.5% fat. The several prepared media differed mainly in the amount of citrate and whey proteins. Fermentation was carried out at room temperature until the media reached pH value of 5. Samples were evaluated for sensory characteristics using quantitative descriptive analysis (QDA. In all media the target pH was reached after 68-71 hours of fermentation, depending on citrate level. Fermentation and the production of aroma compounds were more intensive in media that contained whey proteins compared to media with only casein. Increased citrate level had a positive influence on the aroma production. Citrate increased the initial pH of the media and acted as a buffer during fermentation, which lead to longer fermentation and prolonged production of aroma compounds. At pH around 5, the desired cultured aroma was the most intensive, whereas sour taste was less dominant. The substrate with 0.25% citrate and 0.1% whey proteins, at pH 5, was rated as best regarding its sensory characteristics.

On-line monitoring system of lactic acid fermentation by using integrated enzyme sons ors; Shusekika koso sensa wo mochiita nyusan hakko keisokuyo onrain monitaringu shisutemu

Energy Technology Data Exchange (ETDEWEB)

Suzuki, Masayasu; Kumagi, Takeshi; Nakashima, Yuuichi [Kyushu University, Fukuoka (Japan). Dept. of Biochemical Engineering and Science

1999-03-10

An on-line monitoring system for lactic acid fermentation is developed by using integrated micro enzyme sensors, a flow injection analysis system, and a micro dialysis system. The calibration curves of micro glucose, lactose and lactate sensors show good linearity in the concentration range below 70 mM. By combination with the micro dialysis system, the enzyme sensors can measure the whole concentration range of lactic acid fermentation, and interference by the medium can not be observed. The on-line sensor system is then applied to lactic acid fermentation of Lactobacillus delbrueckii. The sensor system can monitor the glucose and lactate concentrations simultaneously during 24-h fermentation, and the measurements show good agreement with those of the conventional colorimetric method. The sensor system can also be applied to on-line monitoring of lactose and lactate during Lactobacillus lactis fermentation. (author)

Manufacture of a beverage from cheese whey using a "tea fungus" fermentation.

Science.gov (United States)

Belloso-Morales, Genette; Hernández-Sánchez, Humberto

2003-01-01

Kombucha is a sour beverage reported to have potential health effects prepared from the fermentation of black tea and sugar with a "tea fungus", a symbiotic culture of acetic acid bacteria and yeasts. Although black tea is the preferred substrate for Kombucha fermentation, other beverages have also been tested as substrates with fair results. Cheese whey is a by-product with a good amount of fermentable lactose that has been used before in the production of beverages, so the objective of this study was to test three types of whey (fresh sweet, fresh acid and reconstituted sweet) in the elaboration of a fermented beverage using a kombucha culture as inoculum. The isolation and identification of bacteria and yeasts from the fermented tea and wheys was done along with the study of the rates of change in sugar consumption, acid production and pH decrease. Several species of acetic acid bacteria (Acetobacter aceti subsp. aceti, Gluconobacter oxydans subsp. industrius, subsp. oxydans and Gluconoacetobacter xylinus) were isolated from the different kombuchas along with the yeasts Saccharomyces cerevisiae, Kluyveromyces marxianus, and Brettanomyces bruxelensis. The main metabolic products in the fermented wheys included ethanol, lactic and acetic acids. A good growth was obtained in both sweet wheys in which a pH of 3.3 and a total acid content (mainly lactic and acetic acids) of 0.07 mol/l was reached after 96 h. The sweet whey fermented beverages contained a relatively low lactose concentration (< 12 g/l). The final ethanol content was low (5 g/l) in all the fermented wheys. The whey products were strongly sour and salty non sparkling beverages.

The molecular basis of lactose intolerance.

Science.gov (United States)

Campbell, Anthony K; Waud, Jonathan P; Matthews, Stephanie B

2009-01-01

A staggering 4000 million people cannot digest lactose, the sugar in milk, properly. All mammals, apart from white Northern Europeans and few tribes in Africa and Asia, lose most of their lactase, the enzyme that cleaves lactose into galactose and glucose, after weaning. Lactose intolerance causes gut and a range of systemic symptoms, though the threshold to lactose varies considerably between ethnic groups and individuals within a group. The molecular basis of inherited hypolactasia has yet to be identified, though two polymorphisms in the introns of a helicase upstream from the lactase gene correlate closely with hypolactasia, and thus lactose intolerance. The symptoms of lactose intolerance are caused by gases and toxins produced by anaerobic bacteria in the large intestine. Bacterial toxins may play a key role in several other diseases, such as diabetes, rheumatoid arthritis, multiple sclerosis and some cancers. The problem of lactose intolerance has been exacerbated because of the addition of products containing lactose to various foods and drinks without being on the label. Lactose intolerance fits exactly the illness that Charles Darwin suffered from for over 40 years, and yet was never diagnosed. Darwin missed something else--the key to our own evolution--the Rubicon some 300 million years ago that produced lactose and lactase in sufficient amounts to be susceptible to natural selection.

Bio-ethanol production by fermentation of ricotta cheese whey as an effective alternative non-vegetable source

Energy Technology Data Exchange (ETDEWEB)

Sansonetti, Sascha; Curcio, Stefano; Calabro, Vincenza; Iorio, Gabriele [Department of Engineering Modeling, University of Calabria, Ponte P. Bucci, Cubo 42/A, 87036 Rende, Cosenza (Italy)

2009-12-15

The aim of the present paper is to investigate the feasibility of bio-ethanol production by batch fermentation of ricotta cheese whey (''Scotta''), a dairy industry waste characterized by lactose concentration ranging from 4.5% to 5.0% (w/w) and, with respect to traditional (raw) whey, by much lower protein content. Scotta, therefore, could represent an effective non-vegetable source for renewable energy production. The microrganism used to carry out the fermentation processes was the yeast Kluyveromyces marxianus. Preliminary experiments, performed in aerobic conditions on different volumes of scotta, have shown the actual growth of the yeast. The subsequent fermentation experiments were carried out, in anaerobic conditions, on three different substrates: scotta, raw cheese whey and deproteinized whey. The experimental data have demonstrated the process feasibility: scotta is an excellent substrate for fermentation and exhibits better performance with respect to both raw cheese whey and deproteinized whey. Complete lactose consumption, indeed, was observed in the shortest time (13 h) and with the highest ethanol yield (97% of the theoretical value). (author)

Studies on tableting properties of lactose. VII. The effect of variations in primary particle size and percentage of amorphous lactose in spray dried lactose products

NARCIS (Netherlands)

Vromans, H.; Bolhuis, G.K.; Lerk, C.F.; van de Biggelaar, H.; Bosch, H.

1987-01-01

Sieve fractions of α-lactose monohydrate and dicalcium phosphate dihydrate, respectively, suspended in solutions of lactose, were spray dried in order to obtain products with various amorphous lactose contents. The compactibility of the samples appeared to be a function of both the primary particle

Systematic review: effective management strategies for lactose intolerance.

Science.gov (United States)

Shaukat, Aasma; Levitt, Michael D; Taylor, Brent C; MacDonald, Roderick; Shamliyan, Tatyana A; Kane, Robert L; Wilt, Timothy J

2010-06-15

Lactose intolerance resulting in gastrointestinal symptoms is a common health concern. Diagnosis and management of this condition remain unclear. To assess the maximum tolerable dose of lactose and interventions for reducing symptoms of lactose intolerance among persons with lactose intolerance and malabsorption. Multiple electronic databases, including MEDLINE and the Cochrane Library, for trials published in English from 1967 through November 2009. Randomized, controlled trials of individuals with lactose intolerance or malabsorption. Three investigators independently reviewed articles, extracted data, and assessed study quality. 36 unique randomized studies (26 on lactase- or lactose-hydrolyzed milk supplements, lactose-reduced milk, or tolerable doses of lactose; 7 on probiotics; 2 on incremental lactose administration for colonic adaptation; and 1 on another agent) met inclusion criteria. Moderate-quality evidence indicated that 12 to 15 g of lactose (approximately 1 cup of milk) is well tolerated by most adults. Evidence was insufficient that lactose-reduced solution or milk with a lactose content of 0 to 2 g, compared with greater than 12 g, is effective in reducing symptoms of lactose intolerance. Evidence for probiotics, colonic adaptation, and other agents was also insufficient. Most studies evaluated persons with lactose malabsorption rather than lactose intolerance. Variation in enrollment criteria, outcome reporting, and the composition and dosing of studied agents precluded pooling of results and limited interpretation. Most individuals with presumed lactose intolerance or malabsorption can tolerate 12 to 15 g of lactose. Additional studies are needed to determine the effectiveness of lactose intolerance treatment.

[Calcium supplementation uncovering lactose intolerance - a case report].

Science.gov (United States)

Trifina, Eva; Geissler, Dietmar; Zwettler, Elisabeth; Klaushofer, Klaus; Mikosch, Peter

2012-03-01

A 44 yr-old female with osteoporosis had no relevant gastrointestinal symptoms and did not avoid any specific food. However, after prescription of a lactose-rich calcium supplementation, clinical symptoms suspicious for lactose intolerance occurred, which were thereafter confirmed by a lactose tolerance test. Lactose intolerance may present with only slight or subtle symptoms. Drugs containing lactose may induce or increase gastrointestinal symptoms in patients with lactose intolerance. In case of gastrointestinal symptoms occurring after the initiation of drugs containing lactose, the possibility of lactose intolerance should be considered and tested by lactose tolerance test or genetic testing for the LCT (-13910) polymorphism. Due to the prevalence of about 15-25% lactose intolerance in the Austrian population, lactose free drugs should be prescribed as widely as possible.

Is it just lactose intolerance?

Science.gov (United States)

Olivier, Celso Eduardo; Lorena, Sônia Letícia Silva; Pavan, Célia Regina; dos Santos, Raquel Acácia Pereira Gonçalves; dos Santos Lima, Regiane Patussi; Pinto, Daiana Guedes; da Silva, Mariana Dias; de Lima Zollner, Ricardo

2012-01-01

Acquired delayed-onset hypolactasia is a common autosomal recessive condition. Cow's milk allergies, conversely, are less common conditions that may manifest with equivalent symptoms and are able to simulate and/or aggravate lactose intolerance. This study was designed to evaluate the contribution of IgE-mediated cow's milk sensitization to the symptomatology of adult patients with lactose-free diet refractory lactose intolerance. Forty-six adult patients with lactose intolerance and persistent symptoms despite a lactose-free diet underwent skin-prick test to investigate cow's milk, goat's milk, and soy protein-specific-IgE. SDS-PAGE immunoblotting was used to investigate the presence of cow's milk protein-specific IgE. The percentage of patients who had skin reactions to whole cow's milk, alpha-lactalbumin, beta-lactoglobulin, caseins, goat's milk, and soy was 69.5, 36.9, 56.5, 56.5%, 54.3, and 50%, respectively. The percentage of patients with immunoblot-detected IgE specific for alpha-lactalbumin, beta-lactoglobulin, caseins, and bovine serum albumin was 21.7, 63, 67.3, and 2.1%, respectively. IgE-mediated sensitization to cow's milk is a frequent comorbidity in subjects with lactose-free diet refractory lactose intolerance and is worth consideration in patients with this condition.

Characterization of pomegranate juice and whey based novel beverage fermented by kefir grains.

Science.gov (United States)

Sabokbar, Nayereh; Khodaiyan, Faramarz

2015-06-01

Mixture of pomegranate juice and whey was evaluated as a potential substrate for production of a novel probiotic beverage by kefir grains. Different fermentation conditions were used as viz: two fermentation temperature (19 ºC and 25 ºC) and two levels of kefir grains inoculum (5 % and 8%w/v). pH, acidity, lactose consumption as well as organic acids formation were determined during 32 hours of fermentation. Results showed that kefir grains were able to utilize lactose and decrease pH, increase acidity, produce lactic acid and acetic acid, while the level of citric acid decreased. It was observed these change depended on temperature and level of kefir grains with the highest changes at the temperature of 25 ºC and kefir grains inoculum of 8%w/v. Pomegranate juice and whey mixture therefore may serve as a suitable substrate for the production of novel probiotic dairy-fruit juice beverage by kefir grains and the sensory characteristics of this beverage were shown desirable results.

Continuous fermentation of whey into alcohol using an attached film expanded bed reactor

Energy Technology Data Exchange (ETDEWEB)

Chen, H C; Zall, R R

1982-01-01

Batch and continuous processes were studied using a lactose- fermenting yeast, Saccharomyces fragi. Batch methods were used to study the effects of temperature, pH, yeast extract, and ergosterol on ethanol and cell mass production. The optimal temperature ranged from 32 to 37 degrees C. No pH control appeared necessary for whey fermentation. Supplements of yeast extract and ergosterol appeared to have pronounced effect on cell mass and ethanol production. Overall, whey reconstituted from acid whey powder containing 10% lactose could be converted to 36.5 g/l of ethanol in 44 hours when the material was supplemented with 0.7% yeast extract, 10 mg/l ergosterol, and fermented at 32 degrees C using 2.67% aerobically grown inoculum containing approximately 110 x 10 to the power of 6 CFU/ml. Ethanol productivity as high as 6.9 g/lj/h was achieved in a continuous attached film expanded bed fermentor using cellulose acetate as support media. The retention time was 1.1 hour and effluent ethanol concentration was 7.6 g/l. (Refs. 27).

Weak interactions in clobazam–lactose mixtures examined by differential scanning calorimetry: Comparison with the captopril–lactose system

International Nuclear Information System (INIS)

Toscani, S.; Cornevin, L.; Burgot, G.

2012-01-01

Highlights: ► Thermodynamic and kinetic parameters of weak interactions in binary systems by DSC. ► Energy-barrier decrease for lactose dehydration induced by clobazam. ► Recrystallisation of metastable liquid clobazam induced by anhydrous alpha lactose. ► Decrease of lactose dehydration temperature in binary mixtures with captopril. ► Increase of lactose dehydration enthalpy in binary mixtures with captopril. - Abstract: The thermal behaviour of binary mixtures of two drugs (clobazam and captopril, respectively) and a pharmaceutical excipient (lactose monohydrate) was measured with differential scanning calorimetry to determine thermodynamic and kinetic parameters (dehydration and melting enthalpies and dehydration and glass-transition activation energies) which might be affected by intermolecular interactions. A kinetic study showed that lactose dehydration is not a single-step conversion and that clobazam contributed to reduce the energy barrier for the bulk dehydration of the excipient. On the other hand, the physical interactions between metastable liquid clobazam and crystalline anhydrous α-lactose obtained from monohydrate dehydration gave rise to the recrystallisation of clobazam. In the captopril–lactose system, the liquid captopril influenced the lactose dehydration: a sharp increase of the dehydration enthalpy and a concurrent reduction of the dehydration temperature were observed. Finally, it turned out that solid-phase transitions were enhanced by the contact with a liquid phase.

Lactose intolerance: from diagnosis to correct management.

Science.gov (United States)

Di Rienzo, T; D'Angelo, G; D'Aversa, F; Campanale, M C; Cesario, V; Montalto, M; Gasbarrini, A; Ojetti, V

2013-01-01

This review discusses one of the most relevant problems in gastrointestinal clinical practice: lactose intolerance. The role of lactase-persistence alleles the diagnosis of lactose malabsorption the development of lactose intolerance symptoms and its management. Most people are born with the ability to digest lactose, the major carbohydrate in milk and the main source of nutrition until weaning. Approximately, 75% of the world's population loses this ability at some point, while others can digest lactose into adulthood. Symptoms of lactose intolerance include abdominal pain, bloating, flatulence and diarrhea with a considerable intraindividual and interindividual variability in the severity. Diagnosis is most commonly performed by the non invasive lactose hydrogen breath test. Management of lactose intolerance consists of two possible clinical choice not mutually exclusive: alimentary restriction and drug therapy.

Rapid analytical extraction of volatile fermentation products

Energy Technology Data Exchange (ETDEWEB)

Jansen, N B; Flickinger, M C; Tsao, G T

1979-10-01

With renewed interest in production of liquid fuels and chemical feedstocks from carbohydrates, numerous authors have utilized gas-liquid chromatography (GC) for quantification of volatile products. Poor separation and short column life will result if residual sugars present in the medium are not separated from the volatile compounds before injection. In our current investigation of 2,3-butanediol production from xylose, we have developed a rapid GC assay for 2,3-butanediol, acetyl methyl carbinol (acetoin), 2,3-butanedione (diacetyl), and ethanol. This method extracts the fermentation products at high pH from residual xylose before injection into the GC. This routine is a modification of the method of Kolfenbach et al. and is more rapid than the method of separation of diacetyl and acetoin from carbohydrates by distillation reported by Gupta et al. Their erroneous reports of yields of 640 mg diacetyl + acetoin/g sugar are 30% higher than the theoretical maximum for Enterobacter cloacae (ATCC 27613) and points out the need for a reliable, accurate assay for these products.

Chemical oxygen demand reduction in a whey fermentation

Energy Technology Data Exchange (ETDEWEB)

Moresi, M; Colicchio, A; Sansovini, F; Sebastiani, E

1980-01-01

The efficiency of COD reduction in the fermentation of whey by Kluyveromyces fragilis IMAT 1872 was studied at various temperatures, lactose concentrations, air dilution ratios, and stirring speeds. Two different optimal sets of these variables were found according to whether the objective was the production of cell mass or the reduction of COD. The 2 sets were then compared to establish a strategy for the industrial development of this fermentation process. The experimental efficiencies of COD removal were submitted to analysis in a composite design. Only the O2 transfer coefficient factor and the stripping factor were significant. Therefore, the observations were fitted with a quadratic expression by using only these factors: the mean std. error was <6%. The yield of cells varied in this fermentation, but this parameter may be particularly useful for analyzing and optimizing any fermentation process when the culture medium is a mixture of carbohydrates or the main substrate is fully utilized during the initial stages of fermentation.

Effect of increasing dietary nonfiber carbohydrate with starch, sucrose, or lactose on rumen fermentation and productivity of lactating dairy cows.

Science.gov (United States)

Gao, X; Oba, M

2016-01-01

The objective of this study was to investigate effects of increasing dietary nonfiber carbohydrate (NFC) with starch, sucrose, or lactose on rumen fermentation, volatile fatty acid absorption, and milk production of lactating dairy cows. Twenty-eight multiparous, lactating Holstein cows (141 ± 50 d in milk; 614 ± 53 kg of body weight) including 8 ruminally cannulated cows were used in this study. Cows were assigned to 4 dietary treatments in a 4 × 4 Latin square design with 21-d periods. The treatments were control [27% starch and 4% sugar on a dry matter (DM) basis], a high-NFC diet by increasing dietary starch content (STA; 32% starch and 4% sugar on a DM basis), and 2 more high-NFC diets by increasing dietary sugar content (27% starch and 9% sugar on a DM basis) in which sucrose (SUC) or lactose (LAC) was supplemented. Dry matter intake was greater for cows fed high-NFC diets compared with control diet (27.1 vs. 26.3 kg/d), but rumen pH and milk production did not differ between cows fed control and high-NFC diets. However, cows fed high-disaccharide diets had lower mean rumen pH than those fed STA diet (6.19 vs. 6.32). Although molar proportion of butyrate was greater for high-disaccharide treatments than STA treatment (15.2 vs. 13.7 mol/100 mol), absorption rate of volatile fatty acid in the rumen was not affected by treatment. In addition, cows fed high-disaccharide diets had higher energy-corrected milk yield than cows fed STA diet (39.6 vs. 38.0 kg/d). Dry matter intake did not differ between cows fed 2 high-disaccharide diets. Although cows fed the SUC diet had lower molar proportion of butyrate in the rumen compared with those fed the LAC diet (14.4 vs. 15.9 mol/100 mol), the SUC diet did not decrease rumen pH. In addition, cows fed the SUC diet had lower nutrient digestibility of organic matter than did those fed the LAC diet (59.7 vs. 64.4%), but milk component yields did not differ between the 2 high-disaccharide diet treatments. The results of the

Undernourished children and milk lactose

DEFF Research Database (Denmark)

Grenov, Benedikte; Briend, André; Sangild, Per Torp

2016-01-01

BACKGROUND: Lactose is an important energy source in young mammals, and in fully breast-fed human infants, it constitutes around 40% of the total daily energy intake. The role of lactose in feeding of undernourished infants and young children is not well described. OBJECTIVE: A narrative review...... of the potential positive and negative effects of lactose in the treatment of undernourished children. METHODS: Searches were conducted using PUBMED and Web of Science up to July 2015. Relevant references in the retrieved articles were included. RESULTS: Lactose may exhibit several health benefits in young...... children, including a prebiotic effect on the gut microbiota and a positive effect on mineral absorption. Studies in piglets suggest there might also be a stimulating effect on growth, relative to other carbohydrates. Lactose intolerance is a potential concern for undernourished children. Most...

Weak interactions in clobazam-lactose mixtures examined by differential scanning calorimetry: Comparison with the captopril-lactose system

Energy Technology Data Exchange (ETDEWEB)

Toscani, S. [Departement de Chimie - UMR 6226, Faculte des Sciences, Universite de Rennes 1, Batiment 10B, 263 avenue du General Leclerc, F-35042 Rennes Cedex (France); Cornevin, L. [Universite de Rennes 1, Faculte de Pharmacie, 2 Avenue Leon Bernard, F-35043 Rennes Cedex (France); Burgot, G., E-mail: Gwenola.burgot@univ-rennes1.fr [Universite de Rennes 1, Faculte de Pharmacie, Laboratoire de Chimie Analytique, EA 1274 ' Mouvement, sports, sante' , 2 Avenue Leon Bernard, F-35043 Rennes Cedex (France); CHGR Rennes, Pole Medico-Technique Pharmacie, F-35703 Rennes Cedex (France)

2012-09-10

Highlights: Black-Right-Pointing-Pointer Thermodynamic and kinetic parameters of weak interactions in binary systems by DSC. Black-Right-Pointing-Pointer Energy-barrier decrease for lactose dehydration induced by clobazam. Black-Right-Pointing-Pointer Recrystallisation of metastable liquid clobazam induced by anhydrous alpha lactose. Black-Right-Pointing-Pointer Decrease of lactose dehydration temperature in binary mixtures with captopril. Black-Right-Pointing-Pointer Increase of lactose dehydration enthalpy in binary mixtures with captopril. - Abstract: The thermal behaviour of binary mixtures of two drugs (clobazam and captopril, respectively) and a pharmaceutical excipient (lactose monohydrate) was measured with differential scanning calorimetry to determine thermodynamic and kinetic parameters (dehydration and melting enthalpies and dehydration and glass-transition activation energies) which might be affected by intermolecular interactions. A kinetic study showed that lactose dehydration is not a single-step conversion and that clobazam contributed to reduce the energy barrier for the bulk dehydration of the excipient. On the other hand, the physical interactions between metastable liquid clobazam and crystalline anhydrous {alpha}-lactose obtained from monohydrate dehydration gave rise to the recrystallisation of clobazam. In the captopril-lactose system, the liquid captopril influenced the lactose dehydration: a sharp increase of the dehydration enthalpy and a concurrent reduction of the dehydration temperature were observed. Finally, it turned out that solid-phase transitions were enhanced by the contact with a liquid phase.

Production and characterization of aluminium oxide nanoshells on spray dried lactose.

Science.gov (United States)

Hellrup, Joel; Rooth, Mårten; Johansson, Anders; Mahlin, Denny

2017-08-30

Atomic layer deposition (ALD) enables deposition of dense nanometer thick metal oxide nanoshells on powder particles with precise thickness control. This leads to products with low weight fraction coating, also when depositing on nano- or micron sized powder particles. This study aimed at investigating the aluminium oxide nanoshell thickness required to prevent moisture sorption. The nanoshells were produced with ALD on spray-dried lactose, which is amorphous and extremely hygroscopic. The particles were studied with dynamic vapor sorption between 0 and 50% RH, light scattering, scanning electron microscopy, X-ray diffraction, differential scanning calorimetry, and polarized light microscopy. The ALD did not induce any recrystallization of the amorphous lactose. The dynamic vapor sorption indicated that the moisture sorption was almost completely inhibited by the nanoshell. Neat amorphous lactose rapidly recrystallized upon moisture exposure. However, only ca. 15% of the amorphous lactose particles recrystallized of a sample with 9% (by weight) aluminium oxide nanoshell at storage for six months upon 75% RH/40°C, which indicate that the moisture sorption was completely inhibited in the majority of the particles. In conclusion, the aluminium oxide nanoshells prevented moisture sorption and dramatically improved the long term physical stability of amorphous lactose. This shows the potential of the ALD-technique to protect drug microparticles. Copyright © 2017 Elsevier B.V. All rights reserved.

Compaction behaviour and mechanical strength of lactose-sodium starch glycolate and lactose-croscarmellose sodium binary tablets

Science.gov (United States)

Ashikin Yaakub, Nur; Shamsul Anuar, Mohd; Tahir, Suraya Mohd

2018-04-01

The focus of this study is to elucidate the effects of adding super disintegrants (SSG and Acdisol) to a filler (lactose) in terms of the compaction behaviour and mechanical strength of the formed binary tablets. The tablets were formed in a uniaxial die compaction process with compaction pressures ranging from 37.7MPa to 150.7 MPa. Consequently, the findings indicated that the increasing of the compaction pressure and the percentage mass composition of the super disintegrants would led to the increased in the strength of the tablets as well as their plastic energies, where this was more apparent for the case of the binary lactose/Acdisol tablets. In addition, as the compaction pressure increased, the maximum ejection pressure required to eject the tablet from the die cavity also increased. In contrast, a decreased in the maximum ejection pressure was observed as the composition of both super disintegrants increased in the lactose-super disintegrant binary tablets. In conclusion, the addition of super disintegrant; SSG with lactose and Acdisol with lactose; would enhanced the mechanical strength of lactose based tablets especially for the case of acdisol-lactose binary tablets in the experimental conditions adopted in this current work.

Lactose malabsorption and intolerance: pathogenesis, diagnosis and treatment.

Science.gov (United States)

Misselwitz, Benjamin; Pohl, Daniel; Frühauf, Heiko; Fried, Michael; Vavricka, Stephan R; Fox, Mark

2013-06-01

Lactose malabsorption is a common condition caused by reduced expression or activity of lactase in the small intestine. In such patients, lactose intolerance is characterized by abdominal symptoms (e.g. nausea, bloating, and pain) after ingestion of dairy products. The genetic basis of lactose malabsorption is established and several tests for this condition are available, including genetic, endoscopic, and H2-breath tests. In contrast, lactose intolerance is less well understood. Recent studies show that the risk of symptoms after lactose ingestion depends on the dose of lactose, lactase expression, intestinal flora, and sensitivity of the gastrointestinal tract. Lactose intolerance has recently been defined as symptoms developing after ingestion of lactose which do not develop after placebo challenge in a person with lactose maldigestion. Such blinded testing might be especially important in those with functional gastrointestinal diseases in whom self-reported lactose intolerance is common. However, placebo-controlled testing is not part of current clinical practice. Updated protocols and high-quality outcome studies are needed. Treatment options of lactose intolerance include lactose-reduced diet and enzyme replacement. Documenting the response to multiple doses can guide rational dietary management; however, the clinical utility of this strategy has not been tested. This review summarizes the genetic basis, diagnosis, and treatment of lactose malabsorption and intolerance.

Lactose malabsorption and intolerance: pathogenesis, diagnosis and treatment

Science.gov (United States)

Pohl, Daniel; Frühauf, Heiko; Fried, Michael; Vavricka, Stephan R; Fox, Mark

2013-01-01

Lactose malabsorption is a common condition caused by reduced expression or activity of lactase in the small intestine. In such patients, lactose intolerance is characterized by abdominal symptoms (e.g. nausea, bloating, and pain) after ingestion of dairy products. The genetic basis of lactose malabsorption is established and several tests for this condition are available, including genetic, endoscopic, and H2-breath tests. In contrast, lactose intolerance is less well understood. Recent studies show that the risk of symptoms after lactose ingestion depends on the dose of lactose, lactase expression, intestinal flora, and sensitivity of the gastrointestinal tract. Lactose intolerance has recently been defined as symptoms developing after ingestion of lactose which do not develop after placebo challenge in a person with lactose maldigestion. Such blinded testing might be especially important in those with functional gastrointestinal diseases in whom self-reported lactose intolerance is common. However, placebo-controlled testing is not part of current clinical practice. Updated protocols and high-quality outcome studies are needed. Treatment options of lactose intolerance include lactose-reduced diet and enzyme replacement. Documenting the response to multiple doses can guide rational dietary management; however, the clinical utility of this strategy has not been tested. This review summarizes the genetic basis, diagnosis, and treatment of lactose malabsorption and intolerance. PMID:24917953

Characterization of a second physiologically relevant lactose permease gene (lacpB) in Aspergillus nidulans.

Science.gov (United States)

Fekete, Erzsébet; Orosz, Anita; Kulcsár, László; Kavalecz, Napsugár; Flipphi, Michel; Karaffa, Levente

2016-05-01

In Aspergillus nidulans, uptake rather than hydrolysis is the rate-limiting step of lactose catabolism. Deletion of the lactose permease A-encoding gene (lacpA) reduces the growth rate on lactose, while its overexpression enables faster growth than wild-type strains are capable of. We have identified a second physiologically relevant lactose transporter, LacpB. Glycerol-grown mycelia from mutants deleted for lacpB appear to take up only minute amounts of lactose during the first 60 h after a medium transfer, while mycelia of double lacpA/lacpB-deletant strains are unable to produce new biomass from lactose. Although transcription of both lacp genes was strongly induced by lactose, their inducer profiles differ markedly. lacpA but not lacpB expression was high in d-galactose cultures. However, lacpB responded strongly also to β-linked glucopyranose dimers cellobiose and sophorose, while these inducers of the cellulolytic system did not provoke any lacpA response. Nevertheless, lacpB transcript was induced to higher levels on cellobiose in strains that lack the lacpA gene than in a wild-type background. Indeed, cellobiose uptake was faster and biomass formation accelerated in lacpA deletants. In contrast, in lacpB knockout strains, growth rate and cellobiose uptake were considerably reduced relative to wild-type, indicating that the cellulose and lactose catabolic systems employ common elements. Nevertheless, our permease mutants still grew on cellobiose, which suggests that its uptake in A. nidulans prominently involves hitherto unknown transport systems.

Redefining Lactose as a Conditional Prebiotic

Directory of Open Access Journals (Sweden)

Andrew Szilagyi

2004-01-01

Full Text Available Lactose in dairy products is maldigested by up to 70% to 75% of the world's population and many people may therefore suffer symptoms reminiscent of irritable bowel syndrome. As a result, most research to date has concentrated on ways of improving lactose tolerance to enhance dairy as a source of nutrition. However, research on other possible benefits of lactose and its maldigestion has lagged. In view of an exponential growth in the understanding of intestinal microfloral host interactions and the expanding therapeutical potential of probiotics, a reassessment of the role of lactose as a potential prebiotic in lactase nonpersistent subjects is required. Gibson and Roberfroid introduced the concept of prebiotics and outlined definitive requirements for such a compound. The present article examines scientific and clinical knowledge about the properties of lactose and argues that in lactase nonpersistent subjects, lactose qualifies as a prebiotic.

Tableting properties of an improved spray-dried lactose

NARCIS (Netherlands)

Rassu, G.; Eissens, A. C.; Bolhuis, G. K.

2006-01-01

Spray-dried lactose is one of the most widely used filler-binders for direct compaction. The compactibility is a function of both primary particle size and the presence of amorphous lactose. Commercially available spray-dried lactose contains 15-20% amorphous lactose and 80-85% alpha-lactose

Lactose intolerance : analysis of underlying factors

NARCIS (Netherlands)

Vonk, RJ; Priebe, MG; Koetse, HA; Stellaard, F; Lenoir-Wijnkoop, [No Value; Antoine, JM; Zhong, Y; Huang, CY

Background We studied the degree of lactose digestion and orocecal transit time (OCTT) as possible causes for the variability of symptoms of lactose intolerance (LI) in a sample of a population with genetically determined low lactase activity. Methods Lactose digestion index (LDI) was measured by

Rheological properties of lactose-free dairy desserts.

Science.gov (United States)

Sahin, Serpil; Hamamci, Haluk; Garayev, Sultan

2016-10-01

People suffering from lactose intolerance cannot digest milk or lactose-containing foods. Lactose-free diet is essential for them since they do not have the ability to produce lactase to breakdown milk sugar. Physical properties of lactose-free dairy desserts will most probably be different than that of lactose containing ones because of lactose hydrolysis. In this study, it was aimed to analyze the rheological and textural behaviors of different lactose-free dessert formulations containing different gum types and different waxy maize starch and sucrose concentrations. Waxy maize starch was used at concentrations of 0.032 g·mL -1 , 0.040 g·mL -1 , and 0.048 g·mL -1 In addition to waxy maize starch, guar gum, gum arabic, or κ-carrageenan at two different concentrations (1.0% w/w and 0.5% w/w) was added. Sucrose was added at concentrations of 0.14 g·mL -1 and 0.10 g·mL -1 in lactose-free desserts. Power law model was found to be suitable to explain the flow behavior of desserts. The storage and loss modulus of lactose-free desserts were higher than that of lactose-containing desserts. The κ-Carrageenan was found to be the most effective gum for structure build-up. © The Author(s) 2016.

21 CFR 184.1979a - Reduced lactose whey.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Reduced lactose whey. 184.1979a Section 184.1979a... Listing of Specific Substances Affirmed as GRAS § 184.1979a Reduced lactose whey. (a) Reduced lactose whey is the substance obtained by the removal of lactose from whey. The lactose content of the finished...

Biosensor-based analyser. Measurement of glucose, sucrose, lactose, L-lactate and alcohol

Energy Technology Data Exchange (ETDEWEB)

Williams, F.T. Jr. (YSI, Inc., Yellow Springs, OH (United States))

1992-05-01

This paper describes an instrument, the YSI 2700, for the measurement of glucose, sucrose, lactose, L-lactate, and alcohol by means of biosensors. Each biosensor consists of an amperometric, hydrogen peroxide sensitive electrode combined with an immobilized oxidase enzyme trapped between two membranes. Each biosensor differs from the others only in its enzyme layer. The instrument can be used to measure these analytes in complex sample matrices; often directly, e.g. in whole blood and fermentations, after dilution with water, e.g. in molasses and corn syrup, or after extraction into water, e.g. in cheese and cereal products. (orig.).

Adult lactose digestion status and effects on disease

Science.gov (United States)

Szilagyi, Andrew

2015-01-01

BACKGROUND: Adult assimilation of lactose divides humans into dominant lactase-persistent and recessive nonpersistent phenotypes. OBJECTIVES: To review three medical parameters of lactose digestion, namely: the changing concept of lactose intolerance; the possible impact on diseases of microbial adaptation in lactase-nonpersistent populations; and the possibility that the evolution of lactase has influenced some disease pattern distributions. METHODS: A PubMed, Google Scholar and manual review of articles were used to provide a narrative review of the topic. RESULTS: The concept of lactose intolerance is changing and merging with food intolerances. Microbial adaptation to regular lactose consumption in lactase-nonpersistent individuals is supported by limited evidence. There is evidence suggestive of a relationship among geographical distributions of latitude, sunhine exposure and lactase proportional distributions worldwide. DISCUSSION: The definition of lactose intolerance has shifted away from association with lactose maldigestion. Lactose sensitivity is described equally in lactose digesters and maldigesters. The important medical consequence of withholding dairy foods could have a detrimental impact on several diseases; in addition, microbial adaptation in lactase-nonpersistent populations may alter risk for some diseases. There is suggestive evidence that the emergence of lactase persistence, together with human migrations before and after the emergence of lactase persistence, have impacted modern-day diseases. CONCLUSIONS: Lactose maldigestion and lactose intolerance are not synonymous. Withholding dairy foods is a poor method to treat lactose intolerance. Further epidemiological work could shed light on the possible effects of microbial adaptation in lactose maldigesters. The evolutionary impact of lactase may be still ongoing. PMID:25855879

Evaluation of soymilk fermentation with a lactic culture

Directory of Open Access Journals (Sweden)

Martha Cecilia Quicazán

2001-07-01

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

Impurities enhance caking in lactose powder

DEFF Research Database (Denmark)

Carpin, M.; Bertelsen, H.; Dalberg, A.

2017-01-01

Caking of lactose and other dry ingredients is a common problem in the dairy and food industries. The lactose production process includes different purification steps, depending on the type of lactose produced. The aim of this study was therefore to investigate how the remaining impurities (i.......e. non-lactose components) affect the caking tendency of the final powder. The results from a combination of different methods, including dynamic vapor sorption, characterization of the physicochemical composition and assessment of caking with a ring shear tester, suggested humidity caking. Larger...... amounts of impurities in the lactose powder resulted in enhanced moisture sorption and greater caking tendency. These findings emphasize the importance of controlling the washing and purification steps throughout the production process in order to limit caking in the final product...

[Efficacy of Lactose-free Milk in Korean Adults with Lactose Intolerance].

Science.gov (United States)

Park, Sun Hee; Chang, Young Woon; Kim, Soo Jung; Lee, Min Hye; Nam, Ji Hyeok; Oh, Chi Hyuk; Kim, Jung-Wook; Jang, Jae-Young; Yang, Jin Oh; Yoo, Jin Ah; Chung, Jin Young

2016-01-25

Lactose-free milk (LFM) is available for nutrient supply for those with lactose intolerance (LI). However, there are no consistent results of the efficacy of LFM in LI subjects. We aimed to examine the changes of gastrointestinal (GI) symptoms and hydrogen breath test (HBT) values after ingestion of lactose contained milk (LCM) vs. LFM. From May 2015 to September 2015, thirty-five healthy adults with history of LCM-induced GI symptoms were recruited at a tertiary hospital. For the diagnosis of LI, HBT with LCM 550 mL (lactose 25 g) was performed every 20 minutes for 3 hours. The test was defined as "positive" when H2 peak exceeded 20 ppm above baseline values (ΔH2>20 ppm). When the subjects are diagnosed as LI, the second HBT using LFM 550 mL (lactose 0 g) was performed 7 days later. Subjects were asked to complete a questionnaire about the occurrence and severity of GI symptoms. Among a total of 35 subjects, 31 were diagnosed with LI at first visit, and their LCM-related symptoms were abdominal pain (98.6%), borborygmus (96.8%), diarrhea (90.3%), and flatus (87.1%). The ΔH2 value in subjects taking LCM (103.7±66.3ppm) significantly decreased to 6.3±4.9 ppm after ingesting LFM (p<0.0001). There were also significant reduction in total symptom scores and the severity of each symptom when LCM was changed to LFM (p<0.0001). This is the first report that LFM reduce LCM-related GI symptoms and H2 production in Korean adults. LFM can be an effective alternative for LCM in adults with LI.

Comparative genome analysis of Streptococcus infantarius subsp. infantarius CJ18, an African fermented camel milk isolate with adaptations to dairy environment.

Science.gov (United States)

Jans, Christoph; Follador, Rainer; Hochstrasser, Mira; Lacroix, Christophe; Meile, Leo; Stevens, Marc J A

2013-03-22

Streptococcus infantarius subsp. infantarius (Sii) belongs to the Streptococcus bovis/Streptococcus equinus complex associated with several human and animal infections. Sii is a predominant bacterium in spontaneously fermented milk products in Africa. The genome sequence of Sii strain CJ18 was compared with that of other Streptococcus species to identify dairy adaptations including genome decay such as in Streptococcus thermophilus, traits for its competitiveness in spontaneous milk fermentation and to assess potential health risks for consumers. The genome of Sii CJ18 harbors several unique regions in comparison to Sii ATCC BAA-102T, among others an enlarged exo- and capsular polysaccharide operon; Streptococcus thermophilus-associated genes; a region containing metabolic and hypothetical genes mostly unique to CJ18 and the dairy isolate Streptococcus gallolyticus subsp. macedonicus; and a second oligopeptide transport operon. Dairy adaptations in CJ18 are reflected by a high percentage of pseudogenes (4.9%) representing genome decay which includes the inactivation of the lactose phosphotransferase system (lacIIABC) by multiple transposases integration. The presence of lacS and lacZ genes is the major dairy adaptation affecting lactose metabolism pathways also due to the disruption of lacIIABC.We constructed mutant strains of lacS, lacZ and lacIIABC and analyzed the resulting strains of CJ18 to confirm the redirection of lactose metabolism via LacS and LacZ.Natural competence genes are conserved in both Sii strains, but CJ18 contains a lower number of CRISPR spacers which indicates a reduced defense capability against alien DNA. No classical streptococcal virulence factors were detected in both Sii strains apart from those involved in adhesion which should be considered niche factors. Sii-specific virulence factors are not described. Several Sii-specific regions encoding uncharacterized proteins provide new leads for virulence analyses and investigation of the

Comparative genome analysis of Streptococcus infantarius subsp. infantarius CJ18, an African fermented camel milk isolate with adaptations to dairy environment

Science.gov (United States)

2013-01-01

Background Streptococcus infantarius subsp. infantarius (Sii) belongs to the Streptococcus bovis/Streptococcus equinus complex associated with several human and animal infections. Sii is a predominant bacterium in spontaneously fermented milk products in Africa. The genome sequence of Sii strain CJ18 was compared with that of other Streptococcus species to identify dairy adaptations including genome decay such as in Streptococcus thermophilus, traits for its competitiveness in spontaneous milk fermentation and to assess potential health risks for consumers. Results The genome of Sii CJ18 harbors several unique regions in comparison to Sii ATCC BAA-102T, among others an enlarged exo- and capsular polysaccharide operon; Streptococcus thermophilus-associated genes; a region containing metabolic and hypothetical genes mostly unique to CJ18 and the dairy isolate Streptococcus gallolyticus subsp. macedonicus; and a second oligopeptide transport operon. Dairy adaptations in CJ18 are reflected by a high percentage of pseudogenes (4.9%) representing genome decay which includes the inactivation of the lactose phosphotransferase system (lacIIABC) by multiple transposases integration. The presence of lacS and lacZ genes is the major dairy adaptation affecting lactose metabolism pathways also due to the disruption of lacIIABC. We constructed mutant strains of lacS, lacZ and lacIIABC and analyzed the resulting strains of CJ18 to confirm the redirection of lactose metabolism via LacS and LacZ. Natural competence genes are conserved in both Sii strains, but CJ18 contains a lower number of CRISPR spacers which indicates a reduced defense capability against alien DNA. No classical streptococcal virulence factors were detected in both Sii strains apart from those involved in adhesion which should be considered niche factors. Sii-specific virulence factors are not described. Several Sii-specific regions encoding uncharacterized proteins provide new leads for virulence analyses and

Lactose uptake driven by galactose efflux in Streptococcus thermophilus: Evidence for a galactose-lactose antiporter

International Nuclear Information System (INIS)

Hutkins, R.W.; Ponne, C.

1991-01-01

Galactose-nonfermenting (Gal - ) Streptococcus thermophilus TS2 releases galactose into the extracellular medium when grown in medium containing excess lactose. Starved and de-energized Gal - cells, however, could be loaded with galactose to levels approximately equal to the extracellular concentration (0 to 50 mM). When loaded cells were separated from the medium and resuspended in fresh broth containing 5 mM lactose, galactose efflux occurred. De-energized, galactose-loaded cells, resuspended in buffer or medium, accumulated [ 14 C]lactose at a greater rate and to significantly higher intracellular concentrations than unloaded cells. Uptake of lactose by loaded cells was inhibited more than that by unloaded cells in the presence of extracellular galactose, indicating that a galactose gradient was involved in the exchange system. When de-energized, galactose-loaded cells were resuspended in carbohydrate-free medium at pH 6.7, a proton motive force (Δp) of 86 to 90 mV was formed, whereas de-energized, nonloaded cells maintained a Δp of about 56 mV. However, uptake of lactose by loaded cells occurred when the proton motive force was abolished by the addition of an uncoupler or in the presence of a proton-translocating ATPase inhibitor. These results support the hypothesis that galactose efflux in Gal - S. thermophilus is electrogenic and that the exchange reaction (lactose uptake and galactose efflux) probably occurs via an antiporter system

The effects of the DDS-1 strain of lactobacillus on symptomatic relief for lactose intolerance - a randomized, double-blind, placebo-controlled, crossover clinical trial.

Science.gov (United States)

Pakdaman, Michael N; Udani, Jay K; Molina, Jhanna Pamela; Shahani, Michael

2016-05-20

Lactose intolerance is a form of lactose maldigestion where individuals experience symptoms such as diarrhea, abdominal cramping, flatulence, vomiting and bowel sounds following lactose consumption. Lactobacillus acidophilus is a species of bacteria known for its sugar fermenting properties. Preclinical studies have found that Lactobacillus acidophilus supplementation may assist in breaking down lactose; however, no human clinical trials exist evaluating its efficacy in alleviating symptoms related to lactose intolerance. The aim of this randomized, double-blind, placebo-controlled, crossover study was to evaluate the effect of a proprietary strain of Lactobacillus acidophilus on relieving discomfort related to lactose intolerance. The study enrolled healthy volunteers between 18 and 75 years of age who complained of lactose intolerance. Screening visits included a lactose challenge visit to confirm eligibility based on a score of 10 or higher on subjective assessment of the following symptoms after lactose challenge: diarrhea, abdominal cramping, vomiting, audible bowel sounds, flatulence, and overall symptoms. Qualified subjects participated in a 2-arm crossover design, with each arm consisting of 4 weeks of intervention of either active or placebo product, with a 2-week washout period during crossover. The study product consisted of the DDS-1 strain of Lactobacillus acidophilus (Nebraska Cultures, Walnut Creek, California). The placebo was formulated from maltodextrin. Study participants were instructed to take the product once daily for 4 weeks. Data collected included subjective symptom scores related to lactose intolerance. Longitudinal comparison between the DDS-1 group and placebo group demonstrated statistically significant reductions in abdominal symptom scores during the 6-h Lactose Challenge at week 4 for diarrhea (p = 0.033), abdominal cramping (p = 0.012), vomiting (p = 0.0002), and overall symptom score (p = 0.037). No adverse

Content of sugar, organic acids and ethanol in fermented milk beverages obtained with different types of kombucha inoculum

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Iličić Mirela D.

2017-01-01

Full Text Available The aim of this study was to examine the influence of different types and concentration of kombucha inoculum on content of sugar, organic acids and ethanol in the fermented beverages produced from milk of 0.9% fat content. Three different kombucha inoculums, cultivated on black tea with addition of sucrose: standard inoculum - 10% (w/w and 15% (w/w, concentrated by microfiltration- 10% (w/w and 15% (w/w, and concentrated by evaporation - 1.5% (w/w and 3.0% (w/w, were applied in the manufacture of fermented milk. Contents of lactose, galactose, glucose, fructose, organic acids, and ethanol in the kombuha fermented milk beverages were determined by the enzyme tests. It was found that the lactose content varied from 3.30 to 4.0 g/100g. All samples showed higher content glucose than fructose. The content of L-lactic acid in the samples ranged from 0.4 to 0.7 g/100g, while significantly lower level of D-lactic and acetic acid were determined in all samples of kombucha fermented milk (<0.06g/100g.[Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 46009

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

Science.gov (United States)

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

2013-10-01

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

Systems Analysis of Lactose Metabolism in Trichoderma reesei Identifies a Lactose Permease That Is Essential for Cellulase Induction

Science.gov (United States)

Ivanova, Christa; Bååth, Jenny A.; Seiboth, Bernhard; Kubicek, Christian P.

2013-01-01

Trichoderma reesei colonizes predecayed wood in nature and metabolizes cellulose and hemicellulose from the plant biomass. The respective enzymes are industrially produced for application in the biofuel and biorefinery industry. However, these enzymes are also induced in the presence of lactose (1,4-0-ß-d-galactopyranosyl-d-glucose), a waste product from cheese manufacture or whey processing industries. In fact, lactose is the only soluble carbon source that induces these enzymes in T. reesei on an industrial level but the reason for this unique phenomenon is not understood. To answer this question, we used systems analysis of the T. reesei transcriptome during utilization of lactose. We found that the respective CAZome encoded all glycosyl hydrolases necessary for cellulose degradation and particularly for the attack of monocotyledon xyloglucan, from which ß-galactosides could be released that may act as the inducers of T. reesei’s cellulases and hemicellulases. In addition, lactose also induces a high number of putative transporters of the major facilitator superfamily. Deletion of fourteen of them identified one gene that is essential for lactose utilization and lactose uptake, and for cellulase induction by lactose (but not sophorose) in pregrown mycelia of T. reesei. These data shed new light on the mechanism by which T. reesei metabolizes lactose and offers strategies for its improvement. They also illuminate the key role of ß-D-galactosides in habitat specificity of this fungus. PMID:23690947

Probiotic Delivery through Fermentation: Dairy vs. Non-Dairy Beverages

Directory of Open Access Journals (Sweden)

Chaminda Senaka Ranadheera

2017-12-01

Full Text Available Probiotics are live microorganisms that, when administered in adequate amounts, confer a health benefit on the host, mainly through the process of replacing or including beneficial bacteria in the gastrointestinal tract. Fermented dairy foods such as yogurt, fermented milk and cheese are the major vehicle in delivering probiotics, and probiotic delivery have been traditionally associated with these fermented dairy foods. Additionally, many other non-dairy probiotic products and non-food form such as capsules, pills and tablets are also available and some of these non-food forms are highly popular among the consumers. Certain non-dairy probiotic foods, especially beverages that are non-fermented products, can also play an important role in probiotic delivery. There is an increasing demand for non-dairy probiotic foods (both fermented and non-fermented including fruit and vegetable juices, soy and certain cereal products due to vegetarianism, lactose intolerance and dairy allergies, as well as interest in low cholesterol foods. In this context, this review mainly focus on the different types of probiotic food products including beverages with special reference to their viability followed by a brief account on the applicability of using fermented and non-fermented beverage products in probiotic delivery.

Lactose intolerance : the role of colonic metabolism

NARCIS (Netherlands)

He, Tao

2006-01-01

Dairy products provide us with calcium and other valuable nutrients. However, they also contain lactose which is maldigested by a large part of the world adult population. The mechanisms by which lactose maldigestion causes symptoms of lactose intolerance are not fully understood. Studies on the

Perception of lactose intolerance in irritable bowel syndrome patients.

Science.gov (United States)

Dainese, Raffaella; Casellas, Francesc; Mariné-Barjoan, Eugènia; Vivinus-Nébot, Mylène; Schneider, Stéphane M; Hébuterne, Xavier; Piche, Thierry

2014-10-01

The importance of lactose malabsorption in irritable bowel syndrome (IBS) is not well defined and these patients often complain of lactose intolerance. To objectively measure lactose malabsorption, a hydrogen breath test (HBT) can be performed, but a discrepancy emerges between the results of the HBT and the symptomatic response during the HBT. To determine in a group of IBS patients whether self-perceived lactose intolerance and the symptomatic response to lactose HBT were conditioned by other factors besides the presence of lactose malabsorption. Oral challenge to lactose (50 g) was tested in 51 IBS patients to assess HBT malabsorption and the symptomatic response to lactose intolerance was scored on a validated questionnaire. Allergological screening for common inhalants and food allergens (including cow's milk) was performed. The presence of psychological factors (e.g. anxiety, depression, fatigue) was evaluated using validated questionnaires. A total of 21 out of 51 patients (41.1%) were self-perceived to be lactose intolerant, 24/51 (47%) had a positive HBT, and 14/51 (27.4%) presented with symptoms of lactose intolerance during HBT. The serological screening for inhalant and food allergens was positive in 6/21 (28.6%) and 4/21 (19%) of patients who self-perceived lactose intolerance and in 5/14 (37.5%) and 3/14 (21.4%) in intolerant patients symptomatic during HBT. Only 1/51 (1.9%) presented evidence of IgE-mediated hypersensitivity to cow's milk. Patients who experienced symptoms of lactose intolerance during HBT presented more severe IBS symptoms [326 (296-398) vs. 215 (126-295) P=0.05] and a higher score of anxiety, depression, and fatigue. Factors influencing the symptoms of lactose intolerance during HBT resulted in an increase in hydrogen produced and in the severity of IBS. In a cohort of 51 IBS patients, the symptoms of lactose intolerance during HBT were influenced by the capacity to absorb lactose and the severity of IBS. Other factors, such as

Obtaining fermented dairy products with the yogurt culture YF-L 812

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INA VASILEAN

2011-07-01

Full Text Available Exopolysaccharides (EPS produced by some lactic acid bacteria cultures can efficiently replace commercial stabilizers for preventing or reducing syneresis, providing fermented milk products with suitable structure viscosity. The effect of EPS on food quality characteristics depends on the EPS properties themselves, as well as their interaction with various components of the food system. This paper was aimed at studying the influence of the environment composition on the EPS biosynthesis by starter culture YF-L 812 and at determining the properties of at yogurt obtained. High fat content of milk (3.5% and 1.5% had a positive effect on yogurt texture. In order to reduce the syneresis phenomenon, the milk with low fat content (0.1% was supplemented with different concentrations of milk powder and lactose. Our results indicated that the whey separated was reduced to 0.6% and 0.3% when the milk was supplemented with 2% lactose and 2% skimmed milk powder, and respectively, 3% lactose and 3% skimmed milk powder.

Predictors of response to a low-FODMAP diet in patients with functional gastrointestinal disorders and lactose or fructose intolerance.

Science.gov (United States)

Wilder-Smith, C H; Olesen, S S; Materna, A; Drewes, A M

2017-04-01

Diets low in fermentable sugars (low-FODMAP diets) are increasingly adopted by patients with functional gastrointestinal disorders (FGID), but outcome predictors are unclear. To identify factors predictive of an efficacious response to a low-FODMAP diet in FGID patients with fructose or lactose intolerance thereby gaining insights into underlying mechanisms. Fructose and lactose breath tests were performed in FGID patients to determine intolerance (positive symptom score) and malabsorption (increased hydrogen or methane concentrations). Patients with fructose or lactose intolerance consumed a low-FODMAP diet and global adequate symptom relief was assessed after 6-8 weeks and correlated with pre-diet clinical symptoms and breath test results. A total of 81% of 584 patients completing the low-FODMAP diet achieved adequate relief, without significant differences between FGID subgroups or types of intolerance. Univariate analysis yielded predictive factors in fructose intolerance (chronic diarrhoea and pruritus, peak methane concentrations and fullness during breath tests) and lactose intolerance (peak hydrogen and methane concentrations and flatulence during breath tests). Using multivariate analysis, symptom relief was independently and positively predicted in fructose intolerance by chronic diarrhoea [odds ratio (95% confidence intervals): 2.62 (1.31-5.27), P = 0.007] and peak breath methane concentrations [1.53 (1.02-2.29), P = 0.042], and negatively predicted by chronic nausea [0.33 (0.16-0.67), P = 0.002]. No independent predictive factors emerged for lactose intolerance. Adequate global symptom relief was achieved with a low-FODMAP diet in a large majority of functional gastrointestinal disorders patients with fructose or lactose intolerance. Independent predictors of a satisfactory dietary outcome were only seen in fructose intolerant patients, and were indicative of changes in intestinal host or microbiome metabolism. © 2017 John Wiley & Sons Ltd.

Lactose intolerance in Indonesian children.

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Hegar, Badriul; Widodo, Ariani

2015-01-01

"Lactose intolerance (LI)" is considered a common problem in Asians, and in many parts of the world. Its prevalence and age of manifestation varies between by Asian country, for possible genetic or cultural reasons. Studies in Indonesian children 3-15 years old (y) are available within the past two decades, using a pure lactose tolerance test. The prevalences of lactose malabsorption (LM) in pre-elementary (3-5 y), elementary (6-11 y), and junior high (12-14 y) school-children were 21.3%, 57.8%, and 73%, respectively. An increasing trend for LM prevalence was seen within the pre-elementary group, from 9.1% at 3 y to 28.6% at 5 y. The most frequent symptoms of LI in junior high school (JHS) group were abdominal pain (64.1%), abdominal distention (22.6%), nausea (15.1%), flatulence (5.7%), and diarrhea (1.9%), mostly within one hour of lactose ingestion. In children with regular and irregular milk drinking, LM occurred in 81.2% and 69.6%; LI was found in 56.2% and 52.1%, respectively. Most JHS children with dairy-associated recurrent abdominal pain (RAP) symptoms proved to be malabsorbers. Dairy products most related to RAP were milk and yogurt. LI was found in 81% of RAP children with abdominal pain most frequently, followed by nausea, bloating, diarrhea, borborygmi, and flatulence. Symp-tom onset occurred 30 minutes after lactose ingestion, especially nausea, bloating, and abdominal pain. In RAP children LI symptoms mostly found in breath hydrogen concentration>20 ppm. More LI symptoms were found in lactose malabsorbers, but symptoms were mild and generally disappeared in 7 hours, and in most by 15 hours.

Dynamics of lactose changes during ripening of Edam cheese

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Lenka Vorlová

2017-01-01

Full Text Available The published data show that milk and dairy products are an important part of the diet in the European population and the population of North America, where they cover from 20 to 30% of protein, 15% of lipids and about 80% of calcium from food sources. The exclusion of milk and dairy products from human diet due to lactose intolerance (approximately 75% of the global population are lactose malabsorbers can cause very serious health consequences. From a public health point of view, it is therefore extremely important for diary products to capture all the facts about the fluctuation process or rather reduction of lactose content during dairy production technology. The aim of our study was to determine the lactose in various stages of Edam cheese ripening, to assess its suitability for consumption on the afflicted population. For the determination of lactose (day of production, first, second and sixth month of storage the reference enzymatic method using the enzymatic set Megazyme International Ireland with a detection limit of 0.00296 g.100 g-1was applied. This set is intended for determination of lactose in samples presented as low-lactose or lactose-free products and is based on the hydrolysis of lactose to D-galactose and D-glucose by the enzyme β-galactosidase. After the subsequent oxidation of galactose, the amount of formed NADH (stoichiometrically related to the amount of lactose contained in the sample is measured in a spectrophotometer at 340 nm.  According to current legislation, the lactose-free product must contain less than 10 mg of lactose per 100 g or 100 mL of the consumed product, while a product that contains up to 1 g of lactose in 100 g or 100 mL of the product consumed is considered as a product with low lactose content. The study results showed that even after one month of storage Edam cheese can be, according to current national and EU legislation, designated as a lactose-free food. This means that the consumer receives a

Effect of pelvic irradiation of lactose absorption

International Nuclear Information System (INIS)

Stryker, J.A.; Mortel, R.; Hepner, G.W.

1978-01-01

Twenty-four patients undergoing pelvic irradiation for gynecologic malignancies had 14 C-lactose breath tests performed in the first and fifth weeks of their treatment. The 14 C-lactose breath test was performed by administering 2 μCi of 14 C-lactose by mouth along with 50 g of lactose. Breath samples were collected in ethanolic hyamine 1, 2, and 3 hr later; the radioactivity of the trapped 14 CO 2 was determined by liquid scintillation spectroscopy. In the first week of treatment the percentage of administered 14 C excreted as 14 CO 2 at 1, 2, and 3 hr was 1.7 +- 0.8% (mean +- SD), 4.5 +- 1.6%, and 5.8 +- 1.4%, respectively. In the fifth week of treatment the 1-hr, 2-hr, and 3-hr values were 1.2 +- 0.9%, 3.6 +- 2.0%, and 4.7 +- 1.9%, respectively. The difference between the first week and fifth week test results at 1, 2, and 3 hr was statistically significant (t = 2.64, p 14 C-lactose breath test results in the fifth week and the stool frequency at that time (r = -0.44, p 14 C-lactose breath test results in the fifth week were below normal (<1.2%) had nausea at that time. The data suggest that in some patients, lactose malabsorption as a result of the effect of radiation on small intestinal function may be etiologically related to the symptoms of nausea and diarrhea which occur commonly in patients who are undergoing pelvic irradiation. In addition, the results suggest that lactose-containing foods should be restricted in some patients who are undergoing pelvic irradiation to prevent symptoms resulting from radiation-induced lactose intolerance

Lactase Non-persistence and Lactose Intolerance.

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Bayless, Theodore M; Brown, Elizabeth; Paige, David M

2017-05-01

To evaluate the clinical and nutritional significance of genetically determined lactase non-persistence and potential lactose and milk intolerance in 65-70% of the world's adult population. Milk consumption is decreasing in the USA and is the lowest in countries with a high prevalence of lactase non-persistence. The dairy industry and Minnesota investigators have made efforts to minimize the influence of lactose intolerance on milk consumption. Some lactose intolerant individuals, without co-existent irritable bowel syndrome, are able to consume a glass of milk with a meal with no or minor symptoms. The high frequency of lactase persistence in offspring of Northern European countries and in some nomadic African tribes is due to mutations in the promoter of the lactase gene in association with survival advantage of milk drinking. Educational and commercial efforts to improve calcium and Vitamin D intake have focused on urging consumption of tolerable amounts of milk with a meal, use of lowered lactose-content foods including hard cheeses, yogurt, and lactose-hydrolyzed milk products.

Fermentative capabilities and volatile compounds produced by Kloeckera/Hanseniaspora and Saccharomyces yeast strains in pure and mixed cultures during Agave tequilana juice fermentation.

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González-Robles, Ivonne Wendolyne; Estarrón-Espinosa, Mirna; Díaz-Montaño, Dulce María

2015-09-01

The fermentative and aromatic capabilities of Kloeckera africana/Hanseniaspora vineae K1, K. apiculata/H. uvarum K2, and Saccharomyces cerevisiae S1 and S2 were studied in pure and mixed culture fermentations using Agave tequila juice as the culture medium. In pure and mixed cultures, Kloeckera/Hanseniaspora strains showed limited growth and sugar consumption, as well as low ethanol yield and productivity, compared to S. cerevisiae, which yielded more biomass, ethanol and viable cell concentrations. In pure and mixed cultures, S. cerevisiae presented a similar behaviour reaching high biomass production, completely consuming the sugar, leading to high ethanol production. Furthermore, the presence of S. cerevisiae strains in the mixed cultures promoted the production of higher alcohols, acetaldehyde and ethyl esters, whereas Kloeckera/Hanseniaspora strains stimulated the production of ethyl acetate and 2-phenyl ethyl acetate compounds.

Failure to Improve Parameters of Lactose Maldigestion using the Multiprobiotic Product VSL3 in Lactose Maldigesters: A Pilot Study

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Rose Yesovitch

2004-01-01

Full Text Available Lactose maldigestion is a common genetic trait in up to 70% of the world's population. In these subjects, the ingestion of lactose may lead to prebiotic effects which can be confirmed by measurement of breath hydrogen. After a period of continuous lactose ingestion, colonic bacterial adaptation is measurable as improved parameters of lactose digestion. There may be inherent benefits in this process of adaptation which may protect against some diseases. We attempt to link therapeutically beneficial probiotics (VSL3, Seaford Pharmaceuticals Inc, Ontario with improvement in parameters of lactose maldigestion. Two groups of five subjects with maldigestion were fed one or four packets of VSL3 (one packet containing 450x109 live bacteria before testing and then 17 days later. A 50 g lactose challenge was carried out before and after feeding. While there was a trend toward increasing rather than reducing of summed breath hydrogen, no statistically significant changes were observed between results from before testing and those from testing 17 days later. The authors conclude that direct consumption of the probiotic VSL3 may not improve parameters of lactose maldigestion without metabolic activation. In its present format, therefore, the test for colonic adaptation cannot be used to demonstrate direct bacterial embedding with VSL3.

[Lactose intolerance: past and present. Part 1].

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Buzás, György Miklós

2015-09-20

Lactose intolerance is the most prevalent intestinal malabsorption disorder. After presentation of its history, the author describes the emergence of lactose intolerance during the evolution of species, and the biochemistry of lactose as well as features of human and bacterial lactase enzymes are then described. The unequal distribution of lactose intolerance in different continents and population is discussed, followed by presentation of past and present prevalence data in Hungary. Adult-type hypolactasia is caused by a polymorphism of the MCM6 gene located upstream from the lactase gene on the long arm of the chromosome 2. It can be determined with the polymerase chain reaction. The intestinal symptoms of lactose intolerance are well known, but its extra-intestinal manifestations are less recognised. Invasive diagnostic methods (determination of lactase activity from small intestinal biopsies, lactose tolerance test), are accurate, but have been replaced by the non-invasive methods; their gold standard is the H2 breath test. Genetic testing is being used more and more frequently in Hungary too, and, presumably, the methane breath test will be also available in the near future. Lactose intolerance can be accompanied by inflammatory bowel diseases, coeliac disease and irritable bowel syndrome; it could be established whether this association is causal or not in order to start a correct diet and therapy.

Formation of ethanol from lactose by Zymomonas mobilis

Energy Technology Data Exchange (ETDEWEB)

Goodman, A E; Strzelecki, A T; Rogers, P L

1984-01-01

The lactose transposon Tn951 on the IncP plasmid RP1, was introduced into a strain of Zymomonas mobilis. The lac Z gene was expressed and US -galactosidase was produced. The synthesis of US -galactosidase was induced by either isopropyl-US -D-thiogalactopyranoside or lactose, and was not sensitive to catabolite repression. Cells of Zymomonas mobilis containing Tn951 were unable to form colonies on lactose plates, but in liquid medium produced ethanol from lactose as the sole carbon source. The original strain of Zymomonas mobilis without Tn951 produced little or no US -galactosidase and was unable to produce ethanol from lactose in liquid medium.

Development Of A Data Assimilation Capability For RAPID

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Emery, C. M.; David, C. H.; Turmon, M.; Hobbs, J.; Allen, G. H.; Famiglietti, J. S.

2017-12-01

The global decline of in situ observations associated with the increasing ability to monitor surface water from space motivates the creation of data assimilation algorithms that merge computer models and space-based observations to produce consistent estimates of terrestrial hydrology that fill the spatiotemporal gaps in observations. RAPID is a routing model based on the Muskingum method that is capable of estimating river streamflow over large scales with a relatively short computing time. This model only requires limited inputs: a reach-based river network, and lateral surface and subsurface flow into the rivers. The relatively simple model physics imply that RAPID simulations could be significantly improved by including a data assimilation capability. Here we present the early developments of such data assimilation approach into RAPID. Given the linear and matrix-based structure of the model, we chose to apply a direct Kalman filter, hence allowing for the preservation of high computational speed. We correct the simulated streamflows by assimilating streamflow observations and our early results demonstrate the feasibility of the approach. Additionally, the use of in situ gauges at continental scales motivates the application of our new data assimilation scheme to altimetry measurements from existing (e.g. EnviSat, Jason 2) and upcoming satellite missions (e.g. SWOT), and ultimately apply the scheme globally.

Teores de cloretos, lactose e índice cloretos/lactose na secreção láctea de bovinos da raça Jersey no primeiro mês da lactação Chloride and lactose contents and chloride/lactose ratio in milk from Jersey cows in the first month of lactation

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R.F.S. Raimondo

2009-02-01

Full Text Available Avaliou-se a influência do período colostral nos teores lácteos de cloretos, lactose e do índice cloretos/lactose. Foram colhidas 418 amostras de leite provenientes de glândulas mamárias sadias, e que não apresentavam crescimento bacteriano ao exame microbiológico, de 127 vacas da raça Jersey. As amostras foram distribuídas em oito grupos: 0 ┤1/2 dia; 1/2 ┤1 dia; 1 ┤2 dias; 2 ┤3 dias; 3 ┤5 dias; 5 ┤7 dias; 7 ┤15 dias; 15 ┤30 dias em lactação. Nas amostras, colhidas antes da ordenha, foram determinados os valores de cloretos, por titulação colorimétrica, e de lactose, por radiação infravermelho, e calculou-se o índice cloretos/lactose. Nas primeiras 24 horas da lactação, observou-se abrupta diminuição no teor lácteo de cloretos e do índice cloretos/lactose, associada com o aumento no teor lácteo de lactose. A transição da secreção de colostro para leite em relação ao teor de cloretos e lactose e ao índice cloretos/lactose na secreção láctea ocorreu na primeira semana da lactação, a partir do terceiro dia da lactação para o valor de cloretos e para a relação cloretos/lactose e a partir do quarto dia da lactação para o teor de lactose. Recomenda-se, nas primeiras 24 horas da lactação, a adoção dos seguintes limites de normalidade: cloretos, 3,94g/dL e índice cloretos/lactose, 4,03g/dL e índice cloretos/lactose In order to assess the influence of the colostral period on chloride and lactose levels and on the chloride/lactose ratio, 419 milk samples from 127 Jersey cows were analyzed. The samples were collected from healthy udders that did not present any bacterial growth in the microbiological examination. Cows were distributed into eight groups as follows: 0 ┤1/2 day; 1/2 ┤1 day; 1 ┤2 days; 2 ┤3 days; 3 ┤5 days; 5 ┤7 days; 7 ┤15 days; 15 ┤30 days of lactation. The samples were collected before milking to analyze the levels of chloride by colorimetric titration, lactose

Lactose Intolerance: Exploring Reaction Kinetics Governing Lactose Conversion of Dairy Products within the Undergraduate Laboratory

Science.gov (United States)

Smart, Jimmy L.

2008-01-01

Lactose intolerance is a condition suffered by an estimated 50 million Americans. Certain ethnic and racial populations are more widely affected than others. As many as 75 percent of all African-American, Jewish, Native American, and Mexican-American adults, and 90 percent of Asian-American adults are lactose intolerant. Some populations in Africa…

Lactose Intolerance

Science.gov (United States)

... test. Undigested lactose creates lactic acid and other fatty acids that a stool acidity test can detect in ... of Digestive Diseases and Nutrition conducts and supports basic and clinical research into digestive disorders such as ...

Four-sample lactose hydrogen breath test for diagnosis of lactose malabsorption in irritable bowel syndrome patients with diarrhea.

Science.gov (United States)

Yang, Jian-Feng; Fox, Mark; Chu, Hua; Zheng, Xia; Long, Yan-Qin; Pohl, Daniel; Fried, Michael; Dai, Ning

2015-06-28

To validate 4-sample lactose hydrogen breath testing (4SLHBT) compared to standard 13-sample LHBT in the clinical setting. Irritable bowel syndrome patients with diarrhea (IBS-D) and healthy volunteers (HVs) were enrolled and received a 10 g, 20 g, or 40 g dose lactose hydrogen breath test (LHBT) in a randomized, double-blinded, controlled trial. The lactase gene promoter region was sequenced. Breath samples and symptoms were acquired at baseline and every 15 min for 3 h (13 measurements). The detection rates of lactose malabsorption (LM) and lactose intolerance (LI) for a 4SLHBT that acquired four measurements at 0, 90, 120, and 180 min from the same data set were compared with the results of standard LHBT. Sixty IBS-D patients and 60 HVs were studied. The genotype in all participants was C/C-13910. LM and LI detection rates increased with lactose dose from 10 g, 20 g to 40 g in both groups (P lactose doses in both groups. Reducing the number of measurements from 13 to 4 samples did not significantly impact on the accuracy of LHBT in health and IBS-D. 4SLHBT is a valid test for assessment of LM and LI in clinical practice.

Analysis of experimental biosensor/FIA lactose measurements

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Ferreira L.S.

2003-01-01

Full Text Available Whey is an abundant effluent in the production of cheese and casein. The biotechnological utilization of this economically important and nutritive source is limited mainly because of the presence of high percentages of lactose. This disaccharide has poor solubility, which can cause crystallization and insufficient sweetness in dairy food; additionally, part of the adult population suffers from associated lactose intolerance diseases. There are several methods to determine lactose such as spectrophotometry, polarimetry, infrared spectroscopy, titrimetry and chromatography. However these methods are tedious and time-consuming due to long sample preparation. These disadvantages stimulated the development of an enzymatic lactose biosensor. It employs two immobilized enzymes, beta-galactosidase and glucose oxidase and the quantitative analysis of lactose is based on determination of oxygen consumption in the enzymatic reaction. The influence of temperature on the biosensor signal was experimentally studied. It was observed that a nonlinear relationship exists between the electric response of the biosensor - provided by CAFCA (Computer Assisted Flow Control & Analysis - ANASYSCON, Hannover - and lactose concentration. In this work, attempts were made to correlate these variables using a simple nonlinear model and multilayered neural networks, with the latter providing the best modeling of the experimental data.

Blood lactose after dairy product intake in healthy men.

Science.gov (United States)

Pimentel, Grégory; Burton, Kathryn J; Rosikiewicz, Marta; Freiburghaus, Carola; von Ah, Ueli; Münger, Linda H; Pralong, François P; Vionnet, Nathalie; Greub, Gilbert; Badertscher, René; Vergères, Guy

2017-12-01

The absence of a dedicated transport for disaccharides in the intestine implicates that the metabolic use of dietary lactose relies on its prior hydrolysis at the intestinal brush border. Consequently, lactose in blood or urine has mostly been associated with specific cases in which the gastrointestinal barrier is damaged. On the other hand, lactose appears in the blood of lactating women and has been detected in the blood and urine of healthy men, indicating that the presence of lactose in the circulation of healthy subjects is not incompatible with normal physiology. In this cross-over study we have characterised the postprandial kinetics of lactose, and its major constituent, galactose, in the serum of fourteen healthy men who consumed a unique dose of 800 g milk or yogurt. Genetic testing for lactase persistence and microbiota profiling of the subjects were also performed. Data revealed that lactose does appear in serum after dairy intake, although with delayed kinetics compared with galactose. Median serum concentrations of approximately 0·02 mmol/l lactose and approximately 0·2 mmol/l galactose were observed after the ingestion of milk and yogurt respectively. The serum concentrations of lactose were inversely correlated with the concentrations of galactose, and the variability observed between the subjects' responses could not be explained by the presence of the lactase persistence allele. Finally, lactose levels have been associated with the abundance of the Veillonella genus in faecal microbiota. The measurement of systemic lactose following dietary intake could provide information about lactose metabolism and nutrient transport processes under normal or pathological conditions.

Lactose intolerance: diagnosis, genetic, and clinical factors

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Mattar R

2012-07-01

Full Text Available Rejane Mattar, Daniel Ferraz de Campos Mazo, Flair José CarrilhoDepartment of Gastroenterology, University of São Paulo School of Medicine, São Paulo, BrazilAbstract: Most people are born with the ability to digest lactose, the major carbohydrate in milk and the main source of nutrition until weaning. Approximately 75% of the world's population loses this ability at some point, while others can digest lactose into adulthood. This review discusses the lactase-persistence alleles that have arisen in different populations around the world, diagnosis of lactose intolerance, and its symptomatology and management.Keywords: hypolactasia, lactase persistence, lactase non-persistence, lactose, LCT gene, MCM6 gene

GIS/RS-based Rapid Reassessment for Slope Land Capability Classification

Science.gov (United States)

Chang, T. Y.; Chompuchan, C.

2014-12-01

Farmland resources in Taiwan are limited because about 73% is mountainous and slope land. Moreover, the rapid urbanization and dense population resulted in the highly developed flat area. Therefore, the utilization of slope land for agriculture is more needed. In 1976, "Slope Land Conservation and Utilization Act" was promulgated to regulate the slope land utilization. Consequently, slope land capability was categorized into Class I-IV according to 4 criteria, i.e., average land slope, effective soil depth, degree of soil erosion, and parent rock. The slope land capability Class I-VI are suitable for cultivation and pasture. Whereas, Class V should be used for forestry purpose and Class VI should be the conservation land which requires intensive conservation practices. The field survey was conducted to categorize each land unit as the classification scheme. The landowners may not allow to overuse land capability limitation. In the last decade, typhoons and landslides frequently devastated in Taiwan. The rapid post-disaster reassessment of the slope land capability classification is necessary. However, the large-scale disaster on slope land is the constraint of field investigation. This study focused on using satellite remote sensing and GIS as the rapid re-evaluation method. Chenyulan watershed in Nantou County, Taiwan was selected to be a case study area. Grid-based slope derivation, topographic wetness index (TWI) and USLE soil loss calculation were used to classify slope land capability. The results showed that GIS-based classification give an overall accuracy of 68.32%. In addition, the post-disaster areas of Typhoon Morakot in 2009, which interpreted by SPOT satellite imageries, were suggested to classify as the conservation lands. These tools perform better in the large coverage post-disaster update for slope land capability classification and reduce time-consuming, manpower and material resources to the field investigation.

Effects of Wet-Blending on Detection of Melamine in Spray-Dried Lactose.

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Yakes, Betsy Jean; Bergana, Marti M; Scholl, Peter F; Mossoba, Magdi M; Karunathilaka, Sanjeewa R; Ackerman, Luke K; Holton, Jason D; Gao, Boyan; Moore, Jeffrey C

2017-07-19

During the development of rapid screening methods to detect economic adulteration, spray-dried milk powders prepared by dissolving melamine in liquid milk exhibited an unexpected loss of characteristic melamine features in the near-infrared (NIR) and Raman spectra. To further characterize this "wet-blending" phenomenon, spray-dried melamine and lactose samples were produced as a simplified model and investigated by NIR spectroscopy, Raman spectroscopy, proton nuclear magnetic resonance ( 1 H NMR), and direct analysis in real time Fourier transform mass spectrometry (DART-FTMS). In contrast to dry-blended samples, characteristic melamine bands in NIR and Raman spectra disappeared or shifted in wet-blended lactose-melamine samples. Subtle shifts in melamine 1 H NMR spectra between wet- and dry-blended samples indicated differences in melamine hydrogen-bonding status. Qualitative DART-FTMS analysis of powders detected a greater relative abundance of lactose-melamine condensation product ions in the wet-blended samples, which supported a hypothesis that wet-blending facilitates early Maillard reactions in spray-dried samples. Collectively, these data indicated that the formation of weak, H bonded complexes and labile, early Maillard reaction products between lactose and melamine contribute to spectral differences observed between wet- and dry-blended milk powder samples. These results have implications for future evaluations of adulterated powders and emphasize the important role of sample preparation methods on adulterant detection.

LÁCTEOS COM BAIXO TEOR DE LACTOSE: UMA NECESSIDADE PARA PORTADORES DE MÁ DIGESTÃO DA LACTOSE E UM NICHO DE MERCADO

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Mônica Cecília Santana Pereira

2014-06-01

Full Text Available A lactose é o principal carboidrato presente no leite, um alimento composto por nutrientes fundamentais à manutenção da saúde. A intolerância à lactose é o termo habitualmente usado para descrever os sintomas relatados por pessoas que apresentam má digestão da lactose após ingerirem leite e derivados, sendo um tema de extrema relevância para profissionais da área de alimentos, consumidores e profissionais de saúde. Estima-se que 65% da população mundial adulta manifestem sinais e sintomas de má digestão da lactose. Ideias equivocadas sobre sua manifestação e desenvolvimento, induzem a crenças de que o leite e seus derivados devem ser excluídos da alimentação de pessoas que manifestam sintomas de intolerância à lactose. Este artigo visa revisar os principais conceitos relacionados à lactose compreendendo: suas propriedades, importância nutricional e industrial, a distinção entre a má digestão, alergia e a intolerância à lactose, rotulagem, métodos de diagnóstico e de tratamento, bem como a diversidade de produtos com baixos teores de lactose como alternativas para os portadores de má digestão da lactose.

Lactose, galactose and glucose determination in naturally "lactose free" hard cheese: HPAEC-PAD method validation.

Science.gov (United States)

Monti, Lucia; Negri, Stefano; Meucci, Aurora; Stroppa, Angelo; Galli, Andrea; Contarini, Giovanna

2017-04-01

A chromatographic method by HPAEC-PAD was developed and in-house validated for the quantification of low sugar levels in hard cheese, specifically Grana Padano PDO cheese. Particular attention was paid to the extraction procedure, due to residual microbial and enzymatic activities. Specificity in detection and linearity were verified. Recoveries ranged from 93% for lactose to 98% for glucose and galactose. The obtained LOD and LOQ values were, respectively, 0.25 and 0.41mg/100g for lactose, 0.14 and 0.27mg/100g for galactose, and 0.16 and 0.26mg/100g for glucose. The method was applied to 59 samples of Grana Padano PDO cheese: galactose showed the highest concentration and variability among the samples (1.36±0.89), compared to both lactose (0.45±0.12) and glucose (0.46±0.13). Considering the very low levels of sugars detected, authentic PDO Grana Padano could be safely included in the diet of people suffering from lactose intolerance. Copyright © 2016 Elsevier Ltd. All rights reserved.

Monitoring on-line system for the lactic fermentation measurement using the integration enzyme sensor; Shusekika koso sensa wo mochiita nyusan hakko keisokuyo onrain monitringu shisutemu

Energy Technology Data Exchange (ETDEWEB)

Suzuki, Masayasu; Kumagaya, Tsuyoshi; Nakajima, Yoichi [Kyushu Institute of Technology, Fukuoka (Japan)

1999-04-05

The monitoring on-line system for the lactic fermentation measurement in which the simultaneous measurement of the substrate. Generation was possible was constructed without consuming the culture medium by using soliciting small enzyme sensor and flow injection analysis system integrate. There was the linearity that anyway was also range of concentration of 70mM or less and that it is good on the calibration curve of minute glucose, lactose, and lactic acid sensor. It became clear that it proved that all range of concentration of the substrate of these three which combining with the micro diary system, breaks in the lactic fermentation measurement with the necessity can be measured and not observe the interference by medium components, etc. either. Constructed monitoring on-line system is Lactobacillus delbrueckii and, it was applied to the lactic fermentation process of Lactobacillus lactis. Through the fermentation process for 24 hours, simultaneous measurement of glucose (or lactose) and lactic acid is possible. The measured value agreed well with the result of colorimetric method using the enzyme. (translated by NEDO)

What People with Lactose Intolerance Need to Know about Osteoporosis

Science.gov (United States)

... Lactose Intolerance Need to Know About Osteoporosis What People With Lactose Intolerance Need to Know About Osteoporosis ... 2 hours after eating dairy products containing lactose, people with lactose intolerance start to develop stomach cramps ...

Separation of 3′-sialyllactose and lactose by nanofiltration: A trade-off between charge repulsion and pore swelling induced by high pH

DEFF Research Database (Denmark)

Nordvang, Rune Thorbjørn; Luo, Jianquan; Zeuner, Birgitte

2014-01-01

Separation of 3′-sialyllactose (SL) and lactose is an essential final step for the production of the next generation of infant formulas containing sialyllated prebiotics. Due to the difference in molecular weight (MW) between SL and lactose and the charge density of SL, nanofiltration could provide...... a rapid, inexpensive alternative for the separation of SL and lactose compared to traditional chromatography. The performance of four commercial nanofiltration membranes (NF45, DSS-ETNA01PP, NTR-7540 and NP010) for the separation of SL and lactose was assessed at various pH. The difference in retention...... between SL and lactose was only significant in the NP010 and NTR-7450 membranes, whereas the NF45 and DSS ETNA01PP membranes exhibited either too high lactose retention (i.e. insufficient separation) or too low SL retention (i.e. losing the target SL compound), respectively. Operation at increased pH did...

Application of response surface methodology in optimization of lactic acid fermentation of radish: effect of addition of salt, additives and growth stimulators.

Science.gov (United States)

Joshi, V K; Chauhan, Arjun; Devi, Sarita; Kumar, Vikas

2015-08-01

Lactic acid fermentation of radish was conducted using various additive and growth stimulators such as salt (2 %-3 %), lactose, MgSO4 + MnSO4 and Mustard (1 %, 1.5 % and 2 %) to optimize the process. Response surface methodology (Design expert, Trial version 8.0.5.2) was applied to the experimental data for the optimization of process variables in lactic acid fermentation of radish. Out of various treatments studied, only the treatments having ground mustard had an appreciable effect on lactic acid fermentation. Both linear and quadratic terms of the variables studied had a significant effect on the responses studied. The interactions between the variables were found to contribute to the response at a significant level. The best results were obtained in the treatment with 2.5 % salt, 1.5 % lactose, 1.5 % (MgSO4 + MnSO4) and 1.5 % mustard. These optimized concentrations increased titrable acidity and LAB count, but lowered pH. The second-order polynomial regression model determined that the highest titrable acidity (1.69), lowest pH (2.49) and maximum LAB count (10 × 10(8) cfu/ml) would be obtained at these concentrations of additives. Among 30 runs conducted, run 2 has got the optimum concentration of salt- 2.5 %, lactose- 1.5 %, MgSO4 + MnSO4- 1.5 % and mustard- 1.5 % for lactic acid fermentation of radish. The values for different additives and growth stimulators optimized in this study could successfully be employed for the lactic acid fermentation of radish as a postharvest reduction tool and for product development.

Influence of lactose hydrolysis on galacto-oligosaccharides, lactose, volatile profile and physicochemical parameters of different yogurt varieties.

Science.gov (United States)

Vénica, Claudia I; Wolf, Irma V; Bergamini, Carina V; Perotti, María C

2016-12-01

Different types of reduced-lactose yogurt, obtained by lactose hydrolysis using β-galactosidase enzyme, are commercially available. The breakdown of lactose modifies the carbohydrate profile, including the production of prebiotic galacto-oligosaccharides (GOS), which could affect the survival and activity of starter and probiotic cultures and the parameters of yogurt quality. The extension of these changes is dependent on the yogurt matrix composition. This study aimed to evaluate the influence of lactose hydrolysis on GOS, lactose, volatile profile and physicochemical parameters of different yogurt varieties during storage. The presence of β-galactosidase enzyme did not affect either the global composition or the survival of cultures. Overall, the hydrolyzed products had lower acidity than traditional ones. GOS were found at similar levels in fresh hydrolyzed yogurts, whereas in traditional yogurts they were not detected. The proportion of ketones, acids and aldehydes seems to be more dependent on yogurt variety than on addition of the enzyme. Likewise, the storage period affected the volatile fraction to different degree; the increase in acid compounds was more pronounced in hydrolyzed than in traditional yogurts. This work shows that it is possible to obtain different varieties of reduced-lactose yogurt, some of them with additional benefits to health such as reduced fat, reduced calories, added with probiotic/inulin and enriched in GOS, with similar characteristics to traditional products. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA); Scientific Opinion on the substantiation of health claims related to foods with reduced lactose content and decreasing gastro-intestinal discomfort caused by lactose intake in lactose intolerant individuals (ID 646, 1224, 1238, 1339

DEFF Research Database (Denmark)

Tetens, Inge

claims in relation to foods with reduced lactose content and decreasing gastro-intestinal discomfort caused by lactose intake in lactose intolerant individuals. The scientific substantiation is based on the information provided by the Member States in the consolidated list of Article 13 health claims...... and references that EFSA has received from Member States or directly from stakeholders. The food constituent that is the subject of the health claim is lactose, which should be “decreased” or “reduced” in foods in order to obtain the claimed effect. The Panel considers that lactose is sufficiently characterised....... The claimed effects are “lactose intolerance”, “decrease lactose malabsorption symptoms” and “lactose digestion”. The target population is assumed to be lactose intolerant individuals. The Panel assumes that the claimed effects refer to decreasing gastro-intestinal discomfort caused by lactose intake...

Lactose intolerance: diagnosis, genetic, and clinical factors

Science.gov (United States)

Mattar, Rejane; de Campos Mazo, Daniel Ferraz; Carrilho, Flair José

2012-01-01

Most people are born with the ability to digest lactose, the major carbohydrate in milk and the main source of nutrition until weaning. Approximately 75% of the world’s population loses this ability at some point, while others can digest lactose into adulthood. This review discusses the lactase-persistence alleles that have arisen in different populations around the world, diagnosis of lactose intolerance, and its symptomatology and management. PMID:22826639

LÁCTEOS COM BAIXO TEOR DE LACTOSE: UMA NECESSIDADE PARA PORTADORES DE MÁ DIGESTÃO DA LACTOSE E UM NICHO DE MERCADO

OpenAIRE

Pereira, Mônica Cecília Santana; Brumano, Larissa Pereira; Kamiyama, Carolina Martins; Pereira, João Pablo Fortes; Rodarte, Mirian Pereira; Pinto, Miriam Aparecida de Oliveira

2013-01-01

Lactose is the main carbohydrate in milk, containing in nutrients food to health maintenance. Lactose intolerance is the term commonly used to describe the symptoms reported by people with lactose maldigestion after eating dairy products, being a very important topic for food professionals, consumers and health professionals. It is estimated that 65% of the world adult population manifesting symptoms of lactose maldigestion. Haven misconceptions about its manifestation and development, induci...

Sugar transport across lactose permease probed by steered molecular dynamics

DEFF Research Database (Denmark)

Jensen, Morten Østergaard; Yin, Ying; Tajkhorshid, Emad

2007-01-01

Escherichia coli lactose permease (LacY) transports sugar across the inner membrane of the bacterium using the proton motive force to accumulate sugar in the cytosol. We have probed lactose conduction across LacY using steered molecular dynamics, permitting us to follow molecular and energetic...... details of lactose interaction with the lumen of LacY during its permeation. Lactose induces a widening of the narrowest parts of the channel during permeation, the widening being largest within the periplasmic half-channel. During permeation, the water-filled lumen of LacY only partially hydrates lactose......, forcing it to interact with channel lining residues. Lactose forms a multitude of direct sugar-channel hydrogen bonds, predominantly with residues of the flexible N-domain, which is known to contribute a major part of LacY's affinity for lactose. In the periplasmic half-channel lactose predominantly...

[Lactose intolerance in neonates with non-infectious diarrhea].

Science.gov (United States)

Su, Hui-Min; Jiang, Yi; Hu, Yu-Lian; Yang, Hui; Dong, Tian-Jin

2016-04-01

To investigate the development of lactose intolerance in neonates with non-infectious diarrhea and its association with diarrhea, and to evaluate the diagnostic values of fecal pH value and urine galactose determination for neonatal lactase deficiency. Seventy hospitalized neonates who developed non-infectious diarrhea between October 2012 and June 2015 were enrolled as the diarrhea group, and 162 hospitalized neonates without non-infectious diarrhea were enrolled as the non-diarrhea group. Test paper was used to determine fecal pH value. The galactose oxidase method was used to detect urine galactose. The neonates with positive galactose oxidase were diagnosed with lactase deficiency, and those with lactase deficiency and diarrhea were diagnosed with lactose intolerance. According to the results of urine galactose detection, 69 neonates in the diarrhea group who underwent urine galactose detection were classified into lactose intolerance group (45 neonates) and lactose tolerance group (24 neonates), and their conditions after treatment were compared between the two groups. The follow-up visits were performed for neonates with diarrhea at 3 months after discharge. Fecal pH value and positive rate of urine galactose (65% vs 54%) showed no significant differences between the diarrhea and non-diarrhea groups (P>0.05). Fecal pH value showed no significant difference between the lactose intolerance and lactose tolerance groups (P>0.05), while the neonates in the lactose intolerance group had a significantly longer time to recovery of defecation than those in the lactose tolerance group (Plactose intolerance tends to occur. Determination of fecal pH value has no significance in the diagnosis of lactose intolerance in neonates with diarrhea.

Fermentation performance of engineered and evolved xylose-fermenting Saccharomyces cerevisiae strains

DEFF Research Database (Denmark)

Sonderegger, M.; Jeppsson, M.; Larsson, C.

2004-01-01

Lignocellulose hydrolysate is an abundant substrate for bioethanol production. The ideal microorganism for such a fermentation process should combine rapid and efficient conversion of the available carbon sources to ethanol with high tolerance to ethanol and to inhibitory components in the hydrol......Lignocellulose hydrolysate is an abundant substrate for bioethanol production. The ideal microorganism for such a fermentation process should combine rapid and efficient conversion of the available carbon sources to ethanol with high tolerance to ethanol and to inhibitory components...... in the hydrolysate. A particular biological problem are the pentoses, which are not naturally metabolized by the main industrial ethanol producer Saccharomyces cerevisiae. Several recombinant, mutated, and evolved xylose fermenting S. cerevisiae strains have been developed recently. We compare here the fermentation...

THE INFLUENCE OF THIAMINE IN THE FERMENTATION OF THE WINE YEASTS

Directory of Open Access Journals (Sweden)

Ovidiu Tita

2011-12-01

Full Text Available Due to the enzymatic equipment, the yeast cell produces alcoholic fermentation by the meaning of a zimazic complex which catalyzes in different stages the redox processes of the carbohydrates, which are able to ferment, ultimately leading to ethanol. The fermentation rate is an exponential function being influenced by the cells concentration in the development environment and the starter cultures of micro-organisms. Most of the yeast strains do ferment some substrates rich in hexosanes and oligoglucides: sucrose, maltose, raffinose, lactose and celobiose. The biomass quantity may be increased in various ways. An important aspect in the increasing of the multiplication rate of the yeast cells is the determination of the optimum growing conditions. Some kinetic dependencies, mono and multi-factorial, have been observed; they describe the impact of the concentration of the base components in the nutrient environment, temperature, pH, mixing intensity on the multiplication rate of the yeasts.

A novel combined thermometric and amperometric biosensor for lactose determination based on immobilised cellobiose dehydrogenase.

Science.gov (United States)

Yakovleva, Maria; Buzas, Orsolya; Matsumura, Hirotoshi; Samejima, Masahiro; Igarashi, Kiyohiko; Larsson, Per-Olof; Gorton, Lo; Danielsson, Bengt

2012-01-15

A novel method for lactose determination in milk is proposed. It is based on oxidation of lactose by cellobiose dehydrogenase (CDH) from the basidiomycete Phanerochaete chrysosporium, immobilised in an enzyme reactor. The reactor was prepared by cross-linking CDH onto aminopropyl-silanised controlled pore glass (CPG) beads using glutaraldehyde. The combined biosensor worked in flow injection analysis (FIA) mode and was developed for simultaneous monitoring of the thermometric signal associated with the enzymatic oxidation of lactose using p-benzoquinone as electron acceptor and the electrochemically generated current associated with the oxidation of the hydroquinone formed. A highly reproducible linear response for lactose was obtained between 0.05 mM and 30 mM. For a set of more than 500 samples an R.S.D. of less than 10% was achieved. The assay time was ca. 2 min per sample. The sensor was applied for the determination of lactose in dairy milk samples (milk with a fat content of 1.5% or 3% and also "lactose free" milk). No sample preparation except dilution with buffer was needed. The proposed method is rapid, suitable for repeated use and allows the possibility to compare results from two different detection methods, thus providing a built-in quality assurance. Some differences in the response observed between the methods indicate that the dual approach can be useful in mechanistic studies of redox enzymes. In addition, a dual system opens up interesting possibilities for studies of enzyme properties and mechanisms. Copyright © 2011 Elsevier B.V. All rights reserved.

Simultaneous analysis of carbohydrates and organic acids by HPLC-DAD-RI for monitoring goat's milk yogurts fermentation.

Science.gov (United States)

da Costa, Marion Pereira; Frasao, Beatriz da Silva; Lima, Bruno Reis Carneiro da Costa; Rodrigues, Bruna Leal; Conte Junior, Carlos Adam

2016-05-15

During yogurt manufacture, the lactose fermentation and organic acid production can be used to monitor the fermentation process by starter cultures and probiotic bacteria. In the present work, a simple, sensitive and reproducible high-performance liquid chromatography with dual detectors, diode array detector and refractive index was validated by simultaneous analysis of carbohydrates and organic acids in goat milk yogurts. In addition, pH and bacterial analysis were performed. Separation of all the compounds was performed on an Aminex HPX-87H column (300×7.8 mm, 9 µm) utilizing a 3 mmol L(-1) sulfuric acid aqueous mobile phase under isocratic conditions. Lactose, glucose, galactose, citric, lactic and formic acids were used to evaluate the following performance parameters: selectivity, linearity, precision, limit of detection (LOD), limit of quantification (LOQ), decision limits (CCα), detection capabilities (CCβ), recovery and robustness. For the method application a six goat milk yogurts were elaborated: natural, probiotic, prebiotic, symbiotic, cupuassu fruit pulp, and probiotic with cupuassu fruit pulp. The validated method presented an excellent selectivity with no significant matrix effect, and a broad linear study range with coefficients of determination higher than 0.995. The relative standard deviation was lower than 10% under repeatability and within-laboratory reproducibility conditions for the studied analytes. The LOD of the method was defined from 0.001 to 0.003 µg g(-1), and the LOQ from 0.003 to 0.013 µg g(-1). The CCα was ranged from 0.032 to 0.943 µg g(-1), and the CCβ from 0.053 to 1.604 µg g(-1). The obtained recovery values were from 78% to 119%. In addition, the method exhibited an appropriate robustness for all parameter evaluated. Base in our data, it was concluded that the performance parameters demonstrated total method adequacy for the detection and quantification of carbohydrates and organic acids in goat milk yogurts. The

Characterization of Physical and Mechanical Properties of Miscible Lactose-Sugars Systems.

Science.gov (United States)

Li, Runjing; Roos, Yrjö H; Miao, Song

2017-09-01

Lactose-sugars systems were produced by spray drying. They were lactose, lactose-glucose (4:1) mixtures, lactose-maltose (4:1) mixtures, lactose-sucrose (4:1) mixtures, lactose-trehalose (4:1) mixtures, and lactose-corn syrup solids (CSS) (4:1) mixtures. The physical characteristics, water sorption behavior, glass transition, and mechanical properties of miscible lactose-sugars systems were investigated. Lactose-glucose mixtures had larger particle size than other lactose-sugars systems after spray drying. The presence of glucose or sucrose in lactose-sugars mixtures decreased the glass transition temperatures of amorphous systems, while the presence of maltose and trehalose had only minor impact on the glass transition temperatures. Moreover, glucose accelerated the crystallization of amorphous system at 0.44 a w , but its presence delayed the loss of sorbed water at higher water activities (≥0.54 a w ). Mechanical property study indicated that glucose and sucrose in amorphous system could result in an increase of molecular mobility, while the presence of CSS could decrease the free volume and maintain the stiffness of the miscible systems. © 2017 Institute of Food Technologists®.

In vitro batch fecal fermentation comparison of gas and short-chain fatty acid production using "slowly fermentable" dietary fibers.

Science.gov (United States)

Kaur, Amandeep; Rose, Devin J; Rumpagaporn, Pinthip; Patterson, John A; Hamaker, Bruce R

2011-01-01

Sustained colonic fermentation supplies beneficial fermentative by-products to the distal colon, which is particularly prone to intestinal ailments. Blunted/delayed initial fermentation may also lead to less bloating. Previously, we reported that starch-entrapped alginate-based microspheres act as a slowly fermenting dietary fiber. This material was used in the present study to provide a benchmark to compare to other "slowly fermentable" fibers. Dietary fibers with previous reports of slow fermentation, namely, long-chain inulin, psyllium, alkali-soluble corn bran arabinoxylan, and long-chain β-glucan, as well as starch-entrapped microspheres were subjected to in vitro upper gastrointestinal digestion and human fecal fermentation and measured over 48 h for pH, gas, and short-chain fatty acids (SCFA). The resistant fraction of cooked and cooled potato starch was used as another form of fermentable starch and fructooligosaccharides (FOS) served as a fast fermenting control. Corn bran arabinoxylan and long-chain β-glucan initially appeared slower fermenting with comparatively low gas and SCFA production, but later fermented rapidly with little remaining in the final half of the fermentation period. Long-chain inulin and psyllium had slow and moderate, but incomplete, fermentation. The resistant fraction of cooked and cooled potato starch fermented rapidly and appeared similar to FOS. In conclusion, compared to the benchmark slowly fermentable starch-entrapped microspheres, a number of the purported slowly fermentable fibers fermented fairly rapidly overall and, of this group, only the starch-entrapped microspheres appreciably fermented in the second half of the fermentation period. Consumption of dietary fibers, particularly commercial prebiotics, leads to uncomfortable feelings of bloating and flatulence due to their rapid degradation in our large intestine. This article employs claimed potential slowly fermenting fibers and compares their fermentation rates

Lactose behaviour in the presence of lactic acid and calcium.

Science.gov (United States)

Wijayasinghe, Rangani; Vasiljevic, Todor; Chandrapala, Jayani

2016-08-01

Physical properties of lactose appeared influenced by presence of lactic acid in the system. Some other components such as Ca may further attenuate lactose behaviour and impact its phase transition. A model-based study was thus implemented with varying concentrations of Ca (0·12, 0·072 or 0·035% w/w) and lactic acid (0·05, 0·2, 0·4 or 1% w/w) in establishing the effects of these two main acid whey constituents on lactose phase behaviour. Concentrated solutions (50% w/w) containing lactose, lactic acid and Ca were analysed for thermal behaviour and structural changes by Differential Scanning Colorimetry (DSC) and Fourier Transform Infrared Spectroscopy (FTIR), respectively. Presence of 1% (w/w) lactic acid and 0·12% (w/w) Ca in lactose solution significantly increased the evaporation enthalpy of water, delayed and increased the energy required for lactose crystallisation as compared to pure lactose. FTIR analysis indicated a strong hydration layer surrounding lactose molecules, restricting water mobility and/or inducing structural changes of lactose, hindering its crystallisation. The formation of calcium lactate, which restricts the diffusion of lactose molecules, is also partly responsible. It appears that Ca removal from acid whey may be a necessary step in improving the processability of acid whey.

Lactose in dairy ingredients: Effect on processing and storage stability.

Science.gov (United States)

Huppertz, Thom; Gazi, Inge

2016-08-01

Lactose is the main carbohydrate in the milk of most species. It is present in virtually all dry dairy ingredients, with levels ranging from lactose powders. The presence of lactose has a strong effect on ingredient processing and stability. Lactose can negatively influence powder properties and lead to undesirable effects, such as the stickiness of powder resulting in fouling during drying, or caking and related phenomena during storage. In addition, being a reducing carbohydrate, lactose can also participate in the Maillard reaction with free amino groups of proteins, peptides, and free AA. In this review, the influence of the presence (or absence) of lactose on physiochemical properties of dairy ingredients is reviewed, with particular emphasis on behavior during processing and storage. Particularly important features in this respect are whether lactose is in the (glassy) amorphous phase or in the crystalline phase, which is strongly affected by precrystallization conditions (e.g., in lactose, permeate, and whey powders) and by drying conditions. Furthermore, the moisture content and water activity of the ingredients are important parameters to consider, as they determine both mobility and reactivity, influencing Maillard reactions and concomitant browning, the crystallization of amorphous lactose during storage of dairy ingredients, glass transitions temperatures, and associated stickiness and caking phenomena. For the stickiness and caking, a crucial aspect to take into account is powder particle surface composition in relation to the bulk powder. Lactose is typically underrepresented at the powder surface, as a result of which deviations between observed lactose-induced caking and stickiness temperatures, and determined glass transition temperatures arise. By considering lactose as an integral part of ingredient composition along with all other compositional and environmental properties, lactose behavior in dairy ingredients can be understood, controlled, and

Rapid identification of Chinese Sauce liquor from different fermentation positions with FT-IR spectroscopy

Science.gov (United States)

Li, Changwen; Wei, Jiping; Zhou, Qun; Sun, Suqin

2008-07-01

FT-IR and two-dimensional correlation spectroscopy (2D-IR) technology were applied to discriminate Chinese Sauce liquor from different fermentation positions (top, middle and bottom of fermentation cellar) for the first time. The liquors at top, middle and bottom of fermentation cellar, possessed the characteristic peaks at 1731 cm -1, 1733 cm -1 and 1602 cm -1, respectively. In the 2D correlation infrared spectra, the differences were amplified. A strong auto-peak at 1725 cm -1 showed in the 2D spectra of the Top Liquor, which indicated that the liquor might contain some ester compounds. Different from Top Liquor, three auto-peaks at 1695, 1590 and 1480 cm -1 were identified in 2D spectra of Middle Liquor, which were the characteristic absorption of acid, lactate. In 2D spectra of Bottom Liquor, two auto-peaks at 1570 and 1485 cm -1 indicated that lactate was the major component. As a result, FT-IR and 2D-IR correlation spectra technology provided a rapid and effective method for the quality analysis of the Sauce liquor.

Lactose hydrolysis and milk powder production: technological aspects

Directory of Open Access Journals (Sweden)

Jansen Kelis Ferreira Torres

2017-06-01

Full Text Available The food industry has the challenge and the opportunity to develop new products with reduced or low lactose content in order to meet the needs of a growing mass of people with lactose intolerance. The manufacture of spray dried products with hydrolyzed lactose is extremely challenging. These products are highly hygroscopic, which influence the productivity and conservation of the powders, not to mention the undesirable and inevitable technological problem of constant clogging of drying chambers. The aim of this study was to evaluate the effect of different levels (0%, 25%, 50%, 75% and > 99% of enzymatic lactose hydrolysis on the production and storage of whole milk powder. The samples were processed in a pilot plant and characterized in relation to their composition analysis; to their degree of hydrolysis of lactose; and to their sorption isotherms. The results indicated the hydrolysis of lactose may affect the milk powder production due to a higher extent of powder adhesion within the spray dryer chambers and due to a higher tendency to absorb water during storage.

Improving lactose digestion and symptoms of lactose intolerance with a novel galacto-oligosaccharide (RP-G28): a randomized, double-blind clinical trial.

Science.gov (United States)

Savaiano, Dennis A; Ritter, Andrew J; Klaenhammer, Todd R; James, Gareth M; Longcore, Amy T; Chandler, Justin R; Walker, W Allan; Foyt, Howard L

2013-12-13

Lactose intolerance (LI) is a common medical problem with limited treatment options. The primary symptoms are abdominal pain, diarrhea, bloating, flatulence, and cramping. Limiting dairy foods to reduce symptoms contributes to low calcium intake and the risk for chronic disease. Adaptation of the colon bacteria to effectively metabolize lactose is a novel and potentially useful approach to improve lactose digestion and tolerance. RP-G28 is novel galacto-oligosaccharide (GOS) being investigated to improve lactose digestion and the symptoms of lactose intolerance in affected patients. A randomized, double-blind, parallel group, placebo-controlled study was conducted at 2 sites in the United States. RP-G28 or placebo was administered to 85 patients with LI for 35 days. Post-treatment, subjects reintroduced dairy into their daily diets and were followed for 30 additional days to evaluate lactose digestion as measured by hydrogen production and symptom improvements via a patient-reported symptom assessment instrument. Lactose digestion and symptoms of LI trended toward improvement on RP-G28 at the end of treatment and 30 days post-treatment. A reduction in abdominal pain was also demonstrated in the study results. Fifty percent of RP-G28 subjects with abdominal pain at baseline reported no abdominal pain at the end of treatment and 30 days post treatment (p = 0.0190). RP-G28 subjects were also six times more likely to claim lactose tolerance post-treatment once dairy foods had been re-introduced into their diets (p = 0.0389). Efficacy trends and favorable safety/tolerability findings suggest that RP-G28 appears to be a potentially useful approach for improving lactose digestion and LI symptoms. The concurrent reduction in abdominal pain and improved overall tolerance could be a meaningful benefit to lactose intolerant individuals.

Improving lactose digestion and symptoms of lactose intolerance with a novel galacto-oligosaccharide (RP-G28): a randomized, double-blind clinical trial

Science.gov (United States)

2013-01-01

Background Lactose intolerance (LI) is a common medical problem with limited treatment options. The primary symptoms are abdominal pain, diarrhea, bloating, flatulence, and cramping. Limiting dairy foods to reduce symptoms contributes to low calcium intake and the risk for chronic disease. Adaptation of the colon bacteria to effectively metabolize lactose is a novel and potentially useful approach to improve lactose digestion and tolerance. RP-G28 is novel galacto-oligosaccharide (GOS) being investigated to improve lactose digestion and the symptoms of lactose intolerance in affected patients. Methods A randomized, double-blind, parallel group, placebo-controlled study was conducted at 2 sites in the United States. RP-G28 or placebo was administered to 85 patients with LI for 35 days. Post-treatment, subjects reintroduced dairy into their daily diets and were followed for 30 additional days to evaluate lactose digestion as measured by hydrogen production and symptom improvements via a patient-reported symptom assessment instrument. Results Lactose digestion and symptoms of LI trended toward improvement on RP-G28 at the end of treatment and 30 days post-treatment. A reduction in abdominal pain was also demonstrated in the study results. Fifty percent of RP-G28 subjects with abdominal pain at baseline reported no abdominal pain at the end of treatment and 30 days post treatment (p = 0.0190). RP-G28 subjects were also six times more likely to claim lactose tolerance post-treatment once dairy foods had been re-introduced into their diets (p = 0.0389). Conclusions Efficacy trends and favorable safety/tolerability findings suggest that RP-G28 appears to be a potentially useful approach for improving lactose digestion and LI symptoms. The concurrent reduction in abdominal pain and improved overall tolerance could be a meaningful benefit to lactose intolerant individuals. Study registration ClinicalTrials.gov NCT01113619. PMID:24330605

Lyoluminescence characteristics of lactose

International Nuclear Information System (INIS)

Oommen, I.K.; Sengupta, S.; Iyengar, T.S.

1994-01-01

The lyoluminescence (LL) of lactose shows a linear γ-ray dose response in the range 1-10 4 Gy. LL standardization measurement of lactose with a luminol sensitizer shows a sharp increase in light output in the pH range 10-11. Effects of radical scavengers and oxygen confirm that the radiation-induced free radicals take part in the LL process and oxygen is essential for initiating the LL mechanism. LL emission spectral measurements indicate an energy transfer from diffusing free radicals to sensitizer molecules to produce light. (author)

[Lactose intolerance: past and present. Part II].

Science.gov (United States)

Buzás, György Miklós

2015-10-25

The author summarises the interrelations between lactose intolerance, calcium and vitamin D metabolism and osteoporosis. Lactose intolerance enhances the risk of forearm and hip fractures in some patients. Lactase gene genotype and fracture risk are related in some populations. Calcium and vitamin D supplementation increase bone mineral content and they are justified in children, during pregnancy and lactation, and in postmenopausal women. The intake of milk and milk products could increase the risk of ovarian carcinoma. CC genotype of the lactase gene increased the risk of colorectal carcinoma in Finns; no such effect was observed in British, Spanish and Italian patients. Even small quantities of lactose in drugs (10-750 mg) could elicit intolerance symptoms due to individual susceptibility. In spite of public knowledge and advertising, controlled studies did not prove the beneficial effect of either a lactose-free diet, enzyme supplementation or probiotics in an evidence-based manner. While accepted guidelines are lacking, a personalised therapy is mandatory. In spite of increasing public interest in lactose intolerance, many unknown factors must still be studied.

[Breath tests in children with suspected lactose intolerance].

Science.gov (United States)

Parra, P Ángela; Furió, C Simone; Arancibia, A Gabriel

2015-01-01

Up to 70% of the world population is lactose intolerance. However, there are no epidemiological studies among Chilean pediatric population affected by this condition. Clinical characterization of a series of children who underwent the lactose intolerance breath test for lactose intolerance study, establishing intolerance and malabsorption frequencies, the most frequent symptoms, and test performance depending on the origin. Patients under 18 years old who took the lactose intolerance breath test in the Gastroenterology Laboratory of the Catholic University of Chile, and who were admitted due to clinically suspected lactose intolerance. Malabsorption was considered when there was as an increase of ≥20ppm above the baseline (H2) or ≥34ppm of H2 and methane (CH4) combined. Intolerance was considered when the above was associated with a symptom intensity score ≥7 during registration. The analysis included194 patients aged 1 to17 years of age. Of these, 102 (53%) presented with malabsorption, and 53 (27%) were intolerant. The frequency of lactose intolerance varied from 7.1 to 45.4%, and it occurred more frequently at older ages. The most common reported symptoms were abdominal pain, bloating and rumbling. Lactose malabsorption and intolerance can be investigated from the first years of life using the lactose breath test plus a symptom questionnaire. An increase in the frequency of intolerance with age, and a greater number of positive tests, if they were requested by a gastroenterologist, were observed. Copyright © 2015 Sociedad Chilena de Pediatría. Publicado por Elsevier España, S.L.U. All rights reserved.

Fermented Aloreña Table Olives as a Source of Potential Probiotic Lactobacillus pentosus Strains.

Science.gov (United States)

Montoro, Beatriz Pérez; Benomar, Nabil; Lavilla Lerma, Leyre; Castillo Gutiérrez, Sonia; Gálvez, Antonio; Abriouel, Hikmate

2016-01-01

A collection of 31 Lactobacillus pentosus strains isolated from naturally fermented Aloreña green table olives were screened in depth in the present study for their probiotic potential. Several strains could be considered promising probiotic candidates since they showed good growth capacity and survival under simulated gastro-intestinal conditions (acidic pH of 1.5, up to 4% of bile salts and 5 mM of nitrate), good ability to auto-aggregate which may facilitate their adhesion to host cells as multiple aggregates and the subsequent displacement of pathogens. Moreover, co-aggregation of lactobacilli with pathogenic bacteria was shown with Listeria innocua, Staphylococcus aureus, Escherichia coli , and Salmonella Enteritidis as good defense strategy against gut and food pathogens. Furthermore, they exhibited adherence to intestinal and vaginal cell lines, such property could be reinforced by their capacity of biofilm formation which is also important in food matrices such as the olive surface. Their antagonistic activity against pathogenic bacteria by means of acids and plantaricins, and also their different functional properties may determine their efficacy not only in the gastro-intestinal tract but also in food matrices. Besides their ability to ferment several prebiotics, the new evidence in the present study was their capacity to ferment lactose which reinforces their use in different food matrices including dairy as a dietary adjunct to improve lactose digestibility. Lactobacillus pentosus CF2-10N was selected to have the best probiotic profile being of great interest in further studies. In conclusion, spontaneous fermented Aloreña table olives are considered a natural source of potential probiotic L. pentosus to be included as adjunct functional cultures in different fermented foods.

Fermented Aloreña table olives as a source of potential probiotic Lactobacillus pentosus strains

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Beatriz Pérez Montoro

2016-10-01

Full Text Available A collection of 31 Lactobacillus pentosus strains isolated from naturally fermented Aloreña green table olives were screened in depth in the present study for their probiotic potential. Several strains could be considered promising probiotic candidates since they showed good growth capacity and survival under simulated gastro-intestinal conditions (acidic pH of 1.5, up to 4% of bile salts and 5 mM of nitrate, good ability to auto-aggregate which may facilitate their adhesion to host cells as multiple aggregates and the subsequent displacement of pathogens. Moreover, co-aggregation of lactobacilli with pathogenic bacteria was shown with Listeria innocua, Staphylococcus aureus, Escherichia coli and Salmonella Enteriditis as good defense strategy against gut and food pathogens. Furthermore, they exhibited adherence to intestinal and vaginal cell lines, such property could be reinforced by their capacity of biofilm formation which is also important in food matrices such as the olive surface. Their antagonistic activity against pathogenic bacteria by means of acids and plantaricins, and also their different functional properties may determine their efficacy not only in the gastro-intestinal tract but also in food matrices. Besides their ability to ferment several prebiotics, the new evidence in the present study was their capacity to ferment lactose which reinforces their use in different food matrices including dairy as a dietary adjunct to improve lactose digestibility. Lactobacillus pentosus CF2-10N was selected to have best probiotic profile being of great interest in further studies. In conclusion, spontaneous fermented Aloreña table olives are considered a natural source of potential probiotic Lb. pentosus to be included as adjunct functional cultures in different fermented foods.

Differential Impact of Lactose/Lactase Phenotype on Colonic Microflora

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Andrew Szilagyi

2010-01-01

Full Text Available BACKGROUND: The ability to digest lactose divides the world’s population into two phenotypes that may be risk variability markers for several diseases. Prebiotic effects likely favour lactose maldigesters who experience lactose spilling into their colon.

Lactose reduced ice cream enriched with whey powder

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Ana Claudia Tsuchiya

2017-05-01

Full Text Available Ice cream is a food product that pleases the palate of consumers worldwide. Whey powder (WP has various technological and functional properties. However, WP increases the lactose content of the final products in which it is incorporated and causes grittiness and intolerance in lactose-sensitive individuals. This study aimed to produce ice cream with milk powder (MP replaced by WP (MP/WP, decrease the lactose content by enzymatic hydrolysis and verify the physicochemical and microbiological parameters of the final product. Initially, the variables ?-galactosidase concentration and reaction time were studied for the response of the percentage of lactose hydrolysis in a milk ice cream base, using a full 22 factorial design(FFD.With the reaction conditions defined (0.5 g L-1 of ?-galactosidase at 37 C for 4 hthe sucrose concentration and MP/WP replacement variables were then studied in the ice cream formulation for the percentage of lactose hydrolysis and overrun responses using a 22 FFD. The lactose hydrolysis, which ranged between 86.59-97.97%, was not affected by the MP/WP replacement in the ice cream, whilst the overrun was increased by the MP/WP replacement. The physicochemical and microbiological parameters of the ice cream were either not influenced or positively influenced by lactose hydrolysis and MP/WP replacement.

Diagnosis of genetic predisposition for lactose intolerance by high resolution melting analysis.

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Delacour, Hervé; Leduc, Amandine; Louçano-Perdriat, Andréa; Plantamura, Julie; Ceppa, Franck

2017-02-01

Lactose, the principle sugar in milk, is a disaccharide hydrolyzed by intestinal lactase into glucose and galactose, which are absorbed directly by diffusion in the intestine. The decline of lactase expression (or hypolactasia) in intestinal microvilli after weaning is a normal phenomenon in mammals known as lactase deficiency. It is observed in nearly 75% of the world population and is an inherited autosomal recessive trait with incomplete penetrance. It is caused by SNPs in a regulatory element for lactase gene. In Indo-European, lactase deficiency is associated with rs4982235 SNP (or -13910C>T). The aim of this study is to describe a method based on high resolution melting for rapidly detecting genetic predisposition to lactose intolerance. Analytical performance of the assay was assessed by evaluating within and betwwen-run precision and by comparing the results (n = 50 patients) obtained with the HRM assay to those obtained with the gold standard (Sanger sequencing of the region of interest). In silico prediction of HRM curves was performed to evaluate the potential impact of the other SNPs described within the PCR product on the HRM analytical performances. The assay has good performance (CV lactose intolerance.

NMR Study on the Interaction of Trehalose with Lactose and Its Effect on the Hydrogen Bond Interaction in Lactose

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Eric Morssing Vilén

2013-08-01

Full Text Available Trehalose, a well-known stress-protector of biomolecules, has been investigated for its effect on the mobility, hydration and hydrogen bond interaction of lactose using diffusion-ordered NMR spectroscopy and NMR of hydroxy protons. In ternary mixtures of trehalose, lactose and water, the two sugars have the same rate of diffusion. The chemical shifts, temperature coefficients, vicinal coupling constants and ROE of the hydroxy protons in trehalose, lactose and sucrose were measured for the disaccharides alone in water/acetone-d6 solutions as well as in mixtures. The data indicated that addition of trehalose did not change significantly the strength of the hydrogen bond interaction between GlcOH3 and GalO5' in lactose. Small upfield shifts were however measured for all hydroxy protons when the sugar concentration was increased. The chemical shift of the GlcOH3 signal in lactose showed less change, attributed to the spatial proximity to GalO5'. Chemical exchange between hydroxy protons of lactose and trehalose was observed in the ROESY NMR spectra. Similar effects were observed with sucrose indicating no specific effect of trehalose at the concentrations investigated (73 to 763 mg/mL and suggesting that it is the concentration of hydroxy groups more than the type of sugars which is guiding intermolecular interactions.

Lactose malabsorption and intolerance: What should be the best clinical management?

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Usai-Satta, Paolo; Scarpa, Mariella; Oppia, Francesco; Cabras, Francesco

2012-06-06

Lactose malabsorption (LM) is the incomplete hydrolysis of lactose due to lactase deficiency, which may occur as a primary disorder or secondary to other intestinal diseases. Primary adult-type hypolactasia is an autosomal recessive condition resulting from the physiological decline of lactase activity. Different methods have been used to diagnose LM. Lactose breath test represents the most reliable technique. A recent consensus conference has proposed the more physiological dosage of 25 g of lactose and a standardized procedure for breath testing. Recently a new genetic test, based on C/T13910 polymorphism, has been proposed for the diagnosis of adult-type hypolactasia, complementing the role of breath testing. LM represents a well-known cause of abdominal symptoms although only some lactose malabsorbers are also intolerants. Diagnosing lactose intolerance is not straightforward. Many non-malabsorber subjects diagnose themselves as being lactose intolerant. Blind lactose challenge studies should be recommended to obtain objective results. Besides several studies indicate that subjects with lactose intolerance can ingest up to 15 g of lactose with no or minor symptoms. Therefore a therapeutic strategy consists of a lactose restricted diet avoiding the nutritional disadvantages of reduced calcium and vitamin intake.Various pharmacological options are also available. Unfortunately there is insufficient evidence that these therapies are effective. Further double-blind studies are needed to demonstrate treatment effectiveness in lactose intolerance.

Interrelationship of glyocen metabolism and lactose synthesis in mammary epithelial cells of mice

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Emerman, J T; Bartley, J C; Bissell, M J

1980-01-01

Glycogen metabolism in mammary epithelial cells was investigated (i) by studying the conversion of glucose into glycogen and other cellular products in these cells from virgin, pregnant and lactating mice and (ii) by assaying the enzymes directly involved with glycogen metabolism. We find that: (1) mammary epithelial cells synthesized glycogen at rates up to over 60% that of the whole gland; (2) the rate of this synthesis was modulated greatly during the reproductive cycle, reaching a peak in late pregnancy and decreasing rapidly at parturition, when abundant synthesis of lactose was initiated. We propose that glycogen bynthesis restricts lactose synthesis during late pregnancy by competing successfully for the shared UDP-glucose pool. The physiological advantage of glycogen accumulation during late pregnancy is discussed.

Development of selective and differential medium for Shigella sonnei using three carbohydrates (lactose, sorbitol, and xylose) and X-Gal.

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Na, G N; Kim, S A; Kwon, O C; Rhee, M S

2015-08-01

The aim of this study was to develop a new selective and differential medium for isolating Shigella sonnei (designated 3SD medium). The new medium was based on three carbohydrates (lactose, sorbitol, and xylose) and a chromogenic substrate (5-bromo-4-chloro-3-indolyl-β-D-galactopyranoside, X-Gal). S. sonnei cannot ferment lactose, sorbitol, or xylose, but can ferment X-Gal, which generates turquoise-blue colonies with rough edges. Other bacteria (54 strains of foodborne pathogens and spoilage bacteria) produced visually distinct colonies on 3SD medium (colorless or pink-violet colonies), or their growth was inhibited on 3SD medium. The optimum concentration of 50 mg/L X-Gal was selected because it yielded the highest level of morphological discrimination between S. sonnei and other bacteria, and this concentration was cost-effective. Bile salt concentration optimization was performed using healthy, heat-injured, and acid-injured S. sonnei. The recovery rate differed significantly depending on the bile salt concentration; media containing >1.0 g/L bile salt showed significantly lower recovery of stress-injured cells than medium containing 0.5 g/L bile salt (P<0.05). Growth of all Gram-positive bacteria was inhibited on medium containing 0.5 g/L bile salt; therefore, this concentration was used as the optimal concentration. Previous media used to isolate Shigella spp. (MacConkey, xylose lysine desoxycholate, and Salmonella-Shigella agar) showed poor performance when used to support the growth of injured S. sonnei cells, whereas 3SD medium supported a high growth rate of injured and healthy cells (equivalent to that obtained with nutrient-rich tryptic soy agar). To validate the performance of 3SD medium with real specimens, S. sonnei and other bacteria were spiked into samples such as untreated water, carrot, salad, and oyster. 3SD medium showed superior specificity (100%) and sensitivity (100%) for S. sonnei, and yielded no false-positive or false-negative results

Recent advances on lactose intolerance: Tolerance thresholds and currently available answers.

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Corgneau, M; Scher, J; Ritie-Pertusa, L; Le, D T L; Petit, J; Nikolova, Y; Banon, S; Gaiani, C

2017-10-13

The genetically programmed reduction in lactase activity during adulthood affects 70% of the world adult population and can cause severe digestive disorders, which are the sign of lactose intolerance. Lactose intolerance symptoms vary depending on the residual lactase activity, the small bowel transit time, and especially the amount of ingested lactose. To formulate dairy products suitable for the vast majority of lactose intolerants, it is essential to define lactose intolerance threshold. A recent meta-analysis permitted to show that almost all lactose intolerants tolerate 12 g of lactose in one intake and approximately 18 g of lactose spread over the day. The prevalence and severity of lactose intolerance are probably overestimated by the general public. This misconception usually leads to an unnecessary reduction of dairy foodstuff consumption. Nevertheless, dairy products are essential for health mainly due to their calcium content and the positive influence of probiotic bacteria. The formulation of dairy products suitable for most intolerant and suspicious subjects seems necessary. The use of exogenous enzyme preparations, as well as the consumption of lactose-free products or products rich in probiotic bacteria are proposed as symptom-reducing strategies.

Perception of lactose intolerance impairs health-related quality of life.

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Casellas, F; Aparici, A; Pérez, M J; Rodríguez, P

2016-09-01

Chronic conditions impair perception of well-being. Malabsorption of lactose is the most frequent form of malabsorption and manifests as lactose intolerance. There is a lack of information regarding their impact on self-perception of health. The objective of this study is to determine the subjective impact of self-reported lactose intolerance or objective lactose malabsorption on patient health by using a patient-reported outcome to measure health-related quality of life (HRQOL) and modification of lactose-containing food diet. A 3-year prospective, cross-sectional study was performed in patients referred for a lactose hydrogen breath test. Patients were asked about their subjective opinion relative to their lactose tolerance and completed a validated, specific questionnaire to determine symptoms of intolerance during habitual consumption of dairy. A 50-g lactose breath test was then performed. Patients were grouped as absorbers vs malabsorbers and tolerant vs intolerants. A total of 580 patients were included (median age 30 years, 419 female). Overall, 324 patients (56%) considered themselves lactose intolerant and that perception was associated with avoidance of dairy consumption (55% vs only 9% of self-defined tolerants). Self-perception of intolerance was associated with lower HRQOL scores (median, 60 vs 70, Plactose objective malabsorption was not clearly associated with dairy avoidance (41% of malabsorbers avoided dairy vs 31% of absorbers). However, HRQOL scores were also significantly lower in malabsorbers than in absorbers (60 vs 70 respectively, Plactose intolerance affects the decision to avoid dairy even more than objective malabsorption. However, both self-perception of lactose intolerance and objective lactose malabsorption are associated with poorer perceived quality of life.

Randomized, double-blind clinical trial of a lactose-free and a lactose-containing formula in dietary management of acute childhood diarrhea.

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Simakachorn, Nipat; Tongpenyai, Yothi; Tongtan, Orapin; Varavithya, Wandee

2004-06-01

Refeeding of artificially fed infants with lactose-containing formula after oral rehydration therapy in the treatment of acute diarrhea was concluded to be indifferent to non-lactose formula by a meta-analysis. In Thai as well as Asian infants and children with low lactase level from genetically determinant and with rotavirus infection, lactose malabsorption is most likely to occur and cause delayed recovery. The aim of this study was to compare the effect of a lactose-free and a lactose-containing formula in dietary management of acute childhood diarrhea. A randomized, double-blind clinical trial of 80 male children, formula-fed, aged 3 to 24 months, admitted with acute watery diarrhea and mild or moderate dehydration, was carried out. All children received oral rehydration therapy for the first 4 hours. After appropriate rehydration, they were fed either a lactose-free formula (Dumex Lactose-Free Formula; treatment group, n = 40) or a lactose-containing formula (Dumex Infant Formula; control group, n = 40) in adjunction with oral rehydration solution. In addition, the infants were fed rice gruel as tolerated. Comparisons of duration of diarrhea, weight gain, vomiting, biochemical changes, stool frequency and weight and unscheduled intravenous fluid were made. Three children (2 treatment, and 1 control) dropped out from the study. The total number of unscheduled intravenous infusions were 6 of 80 children (7.5%), including 2 (5.0%) in the treatment group and 4 (10.0%) in the control group. Three children in the control group did not resolve from diarrhea within 7 days of treatment. Rotavirus was identified in approximately 50% of the children in each group. Using survival analysis, the median duration of diarrhea was significantly shortened by 20.5 hours in the treatment group compared to the control group (77.0 hours in the treatment group vs 97.5 hours in the control group; P = 0.002). Significantly decrease in stool frequency and increase in percent weight gain

Prevalence of lactose intolerance in Chile: a double-blind placebo study.

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Latorre, Gonzalo; Besa, Pablo; Parodi, Carmen G; Ferrer, Verónica; Azocar, Lorena; Quirola, Marife; Villarroel, Luis; Miquel, Juan F; Agosin, Eduardo; Chianale, José

2014-01-01

Lactase non-persistence (LNP), or primary hypolactasia, is a genetic condition that mediates lactose malabsorption and can cause lactose intolerance. Here we report the prevalence of lactose intolerance in a double-blind placebo study. The LCT C>T-13910 variant was genotyped by RT-PCR in 121 volunteers and lactose malabsorption was assessed using the hydrogen breath test (HBT) after consuming 25 g of lactose. Lactose intolerance was assessed by scoring symptoms (SS) using a standardized questionnaire following challenge with a lactose solution or saccharose placebo. The LNP genotype was observed in 57% of the volunteers, among whom 87% were HBT⁺. In the HBT⁺ group the median SS was 9 and in the HBT⁻ group the median SS was 3 (p lactose intolerance was defined as the presence of an SS ≥ 6 points after subtracting the placebo effect and 34% of the study population met this definition. The LNP genotype was present in more than half of subjects evaluated and the observed prevalence of lactose intolerance was 34%. © 2014 S. Karger AG, Basel.

Perceived lactose intolerance in adult Canadians: a national survey.

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Barr, Susan I

2013-08-01

Although double-blind studies show that lactose-intolerant individuals can consume moderate quantities of milk products without perceptible symptoms, many who perceive that they are lactose intolerant limit or avoid milk products, potentially compromising calcium and vitamin D intakes. Adult Canadians are at risk of inadequate intakes of these nutrients, but no data exist on the prevalence, correlates, and potential impact of perceived lactose intolerance among Canadians. To address this, a Web-based survey of a population-representative sample of 2251 Canadians aged ≥19 years was conducted. Overall, 16% self-reported lactose intolerance. This was more common in women (odds ratio (OR), 1.84; 95% CI, 1.46-2.33) and in nonwhites (OR, 1.79; 95% CI, 1.24-2.58) and less common in those >50 years of age (OR, 0.71; 95% CI, 0.56-0.90) and in those completing the survey in French (OR, 0.74; 95% CI, 0.56-0.99). Those with self-reported lactose intolerance had lower covariate-adjusted milk product and alternative intakes (mean ± SE; 1.40 ± 0.08 servings·day(-1) vs. 2.33 ± 0.03 servings·day(-1), p lactose intolerance by sex, age, and language preference was unexpected and suggests that some groups may be more vulnerable to the perception that they are lactose intolerant. Regardless of whether lactose intolerance is physiologically based or perceptual, education is required to ensure that calcium intakes are not compromised.

A comparison between lactose breath test and quick test on duodenal biopsies for diagnosing lactase deficiency in patients with self-reported lactose intolerance.

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Furnari, Manuele; Bonfanti, Daria; Parodi, Andrea; Franzè, Jolanda; Savarino, Edoardo; Bruzzone, Luca; Moscatelli, Alessandro; Di Mario, Francesco; Dulbecco, Pietro; Savarino, Vincenzo

2013-02-01

A lactose breath test (LBT) is usually used to diagnose lactase deficiency, and a lactose quick test (LQT) has been proposed as a new test on duodenal biopsies to detect this disorder. We aimed to assess the diagnostic accuracy of LBT and LQT and their ability to predict the clinical response to a lactose-free diet in patients with self-reported lactose intolerance. Fifty-five patients (age 47 ± 14 y; M/F 15/36) underwent upper gastrointestinal endoscopy and 25g-LBT. Two duodenal biopsies were taken to determine lactase deficiency (normal, mild, or severe) by LQT and to rule out other causes of secondary lactose malabsorption. Patients with a positive LBT and normal LQT also underwent a glucose breath test to exclude small intestinal bacterial overgrowth as a cause of the former result. The severity of gastrointestinal symptoms was measured with a GSS questionnaire, under basal condition and 1 month after a lactose-free diet. Lactose malabsorption was detected in 31/51 patients with LBT and in 37/51 patients with LQT (P = NS). Celiac disease was found in 2 patients. Two LBT+ patients showed a positive glucose breath test for small intestinal bacterial overgrowth. Eight patients had a mild hypolactasia by LQT and a negative LBT, but they had a significant improvement of symptoms after diet. LQT and LBT were concordant in 83% of cases and predicted the response to a lactose-free diet in 98% and 81% of the cases, respectively (P = 0.03). LQT is as sensitive as LBT in detecting lactase deficiency; however, it seems to be more accurate than LBT in predicting the clinical response to a lactose-free diet.

The influence of molasses addition on the kinetics of alcoholic fermentation of whey using Kluyveromyces marxianus yeast

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Damir Stanzer

2004-01-01

Full Text Available Kinetics of alcoholic fermentation by yeast Kluyveromyces marxianusZIM 75 in various media based on whey and molasses were monitored. The fermentations were performed under static and semiaerobic conditions at 34°C. Deproteinized whey and molasses were mixed in various proportions to give final sugar mass concentrations of 5%, 10% and 15% in medium. The experiments conducted showed that medium with 10 % of sugar (sucrose:lactose=1:1 is optimal for alcoholic fermentations in static and semiaerobic conditions. The best ethanol yield after 24 hours of fermentation was 4.05 % (V/V in static conditions and 4.9 % (V/V in semiaerobic conditions. The biomass yield was 7.78 g d.m./L in semiaerobic conditions and 3.19 g d.m./L in static conditions.

Batch fermentation of whey ultra filtrate by Lactobacillus helveticus for lactic acid production

Energy Technology Data Exchange (ETDEWEB)

Roy, D; Goulet, J; Le Duy, Q

1986-06-01

Cheese whey ultrafiltrate (WU) was used as the carbon source for the production of lactic acid by batch fermentation with Lactobacillus helveticus strain milano. The fermentation was conducted in a 400 ml fermentor at an agitation rate of 200 revolutions per minute and under conditions of controlled temperature (42 degrees C) and pH. In the whey ultrafiltrate-corn steep liquor (WU-CSL) medium, the optimal pH for fermentation was 5.9. Inoculum propagated in skim milk (SM) medium or in lactose synthetic (LS) medium resulted in the best performance in fermentation (in terms of growth, lactic acid production, lactic acid yield and maximum productivity of lactic acid), as compared to that propagated in glucose synthetic (GS) medium. The yeast extract ultrafiltrate (YEU) used as the nitrogen/growth factor source in the WU medium at 1.5% (w/v) gave the highest maximum productivity of lactic acid of 2.70 g/l-h, as compared to the CSL and the tryptone ultrafiltrate (TU). 27 references.

Dynamics of yeast immobilized-cell fluidized-bed bioreactors systems in ethanol fermentation from lactose-hydrolyzed whey and whey permeate.

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Gabardo, Sabrina; Pereira, Gabriela Feix; Klein, Manuela P; Rech, Rosane; Hertz, Plinho F; Ayub, Marco Antônio Záchia

2016-01-01

We studied the dynamics of ethanol production on lactose-hydrolyzed whey (LHW) and lactose-hydrolyzed whey permeate (LHWP) in batch fluidized-bed bioreactors using single and co-cultures of immobilized cells of industrial strains of Saccharomyces cerevisiae and non-industrial strains of Kluyveromyces marxianus. Although the co-culture of S. cerevisiae CAT-1 and K. marxianus CCT 4086 produced two- to fourfold the ethanol productivity of single cultures of S. cerevisiae, the single cultures of the K. marxianus CCT 4086 produced the best results in both media (Y EtOH/S = 0.47-0.49 g g(-1) and Q P = 1.39-1.68 g L(-1) h(-1), in LHW and LHWP, respectively). Ethanol production on concentrated LHWP (180 g L(-1)) reached 79.1 g L(-1), with yields of 0.46 g g(-1) for K. marxianus CCT 4086 cultures. Repeated batches of fluidized-bed bioreactor on concentrated LHWP led to increased ethanol productivity, reaching 2.8 g L(-1) h(-1).

Is the subjective perception of lactose intolerance influenced by the psychological profile?

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Tomba, C; Baldassarri, A; Coletta, M; Cesana, B M; Basilisco, G

2012-10-01

Symptoms of lactose intolerance are often attributed to lactose malabsorption but, as this relationship has not been demonstrated when a small dose of lactose similar to that contained in one cup of milk is ingested by intolerant patients, psychological factors may play a role in altered symptom perception. To assess the hypothesis that the psychological profile influences the symptoms of lactose intolerance. One hundred and two consecutive patients underwent a 15 g lactose hydrogen breath test to assess lactose malabsorption. The patients recorded the presence and severity of symptoms of lactose intolerance during the breath test using visual analogue scales. The psychological profile was assessed using a psychological symptom checklist, and health-related quality of life by means of the short-form health survey. Lactose malabsorption and intolerance were diagnosed in, respectively, 18% and 29% of the patients. The two conditions were not associated, and the severity of intolerance was even less in the patients with malabsorption. Multivariate logistic analysis showed that a high somatisation t-score was significantly associated with lactose intolerance (odds ratio 4.184; 1.704-10.309); the effects of the other psychological variables and of lactose malabsorption were not statistically significant. Health-related quality of life was significantly reduced in the patients with somatisation, but not in those with lactose malabsorption. The symptoms of lactose intolerance during hydrogen breath testing at a low physiological lactose load, are unrelated to lactose malabsorption, but may reveal a tendency towards somatisation that could impair the quality of life. © 2012 Blackwell Publishing Ltd.

[Determination of lactose intolerance frequency in children with food allergy].

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Hutyra, Tomasz; Iwańczak, Barbara

2008-10-01

Lactose malabsorption and lactose intolerance symptoms are the most common alimentary tract disorders in children. Lactose intolerance is a result of lactase deficiency or lack of lactase and lactose malabsorption. Hypersensitivity in food allergy is connected with the presence of specific IgE (specific antibodies against some allergens) or lymphocytes. Lactose intolerance and food allergy may coexist in the same patient. The aim of this study was determination of lactose intolerance frequency in children with food allergy who were below and above 5 years of age. The number of 87 children with food allergy aged from 0.7 to 18 years were included in the study (48 boys and 39 girls). 51 patients above 5 years of age and 36 patients below 5 years of age were studied. Lactose intolerance symptoms, hydrogen breath test, activity of lactase and villous atrophy were investigated. Decreased absorption of lactose in hydrogen breath test was observed in 28% of children above 5 years of age and in 5% in younger children. Positive result of biological trial in hydrogen breath test was observed in 10% of patients who were below 5 years of age and in 26% patients above 5 years. There was no statistically significant difference in lactose intolerance frequency and in decreased activity of lactase in intestinal mucosa between these two groups. Frequent partial villous atrophy was observed in younger patients (41,38%) than in children above 5 years of age (17.86%). Lactose intolerance was observed in 10% patients who were below 5 years of age and in 26% patients above 5 years of age with food allergy. There was no statistically significant difference between these two groups.

A combination of acid lactase from Aspergillus oryzae and yogurt bacteria improves lactose digestion in lactose maldigesters synergistically: A randomized, controlled, double-blind cross-over trial.

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de Vrese, Michael; Laue, Christiane; Offick, Birte; Soeth, Edlyn; Repenning, Frauke; Thoß, Angelika; Schrezenmeir, Jürgen

2015-06-01

Lactose digestion can be improved in subjects with impaired or completely absent intestinal lactase activity by administration of lactase preparations and particularly of acid lactase, which is active in the stomach, or by yogurt containing live lactic acid bacteria. It is the question, if lactose digestion can be further enhanced by combining these two approaches. We investigated in a randomised, placebo-controlled, double-blind, 5-arm crossover study on 24 lactose malabsorbers with variable degrees of lactase deficiency if different lactase preparations and freeze-dried yogurt culture affect gastrointestinal lactose digestion after consuming moderate amounts of lactose (12.5 g) by assessing hydrogen exhalation over 6 h. Furthermore, symptoms of lactose intolerance (excess gas production, abdominal pain, diarrhoea or nausea) were assessed using validated questionnaires. All preparations increased lactose digestion and reduced peak hydrogen exhalation by -27% (yogurt), -29/-33% (3300/9000 FCC(1) ((1) One FCC hydrolyses about 5 or 1.7-2.5 mg lactose in aquous solution or in (artificial) chyme, respectively, according to the FCC-III method of the Committee on Codex Specifications, Food and Nutrition Board, National Research Council. Food Chemicals Codex, 3rd edition. Washington, DC, National Academy Press, 1981 It cannot precisely be defined how much lactose can be hydrolysed in vivo by the consumption of a certain number of FCC units.) units acid lactase from Aspergillus oryzae) or -46%, respectively (3300 FCC units lactase plus yogurt culture combined), as compared with placebo (p yogurt cultures and acid lactase increases lactose digestion more than either freeze-dried yogurt cultures or acid lactase alone, and more lactose malabsorbers benefited from this effect. Copyright © 2014. Published by Elsevier Ltd.

Research and determination of process parameters of milk lactose hydrolysis

OpenAIRE

Калинина, Елена Дмитриевна; Коваленко, Александр Владимирович

2014-01-01

The researches of enzymatic milk lactose hydrolysis by using the β - galactosidase enzyme are given in the paper. For carrying out a lactose hydrolysis, two β-galactosidase enzyme preparations GODO-YNL2 and Neolactase are offered. For setting lactose hydrolysis parameters, the influence of a pH medium, temperature, enzyme preparation doses, the duration of hydrolyzing the milk lactose affected by the β- galactosidase enzyme preparations, was studied. In terms of effectiveness, adaptability an...

THE RELATIONSHIP BETWEEN BULK-DENSITY AND COMPACTIBILITY OF LACTOSE GRANULATIONS

NARCIS (Netherlands)

ZUURMAN, K; RIEPMA, KA; BOLHUIS, GK; VROMANS, H; LERK, CF

1994-01-01

The relationship between the bulk density and the compactibility of lactose granulations was studied. The granulations were prepared from different alpha-lactose monohydrate and roller dried beta-lactose powders by wet granulation, using different techniques with only water as a binder, or by

Rational and evolutionary engineering approaches uncover a small set of genetic changes efficient for rapid xylose fermentation in Saccharomyces cerevisiae.

Directory of Open Access Journals (Sweden)

Soo Rin Kim

Full Text Available Economic bioconversion of plant cell wall hydrolysates into fuels and chemicals has been hampered mainly due to the inability of microorganisms to efficiently co-ferment pentose and hexose sugars, especially glucose and xylose, which are the most abundant sugars in cellulosic hydrolysates. Saccharomyces cerevisiae cannot metabolize xylose due to a lack of xylose-metabolizing enzymes. We developed a rapid and efficient xylose-fermenting S. cerevisiae through rational and inverse metabolic engineering strategies, comprising the optimization of a heterologous xylose-assimilating pathway and evolutionary engineering. Strong and balanced expression levels of the XYL1, XYL2, and XYL3 genes constituting the xylose-assimilating pathway increased ethanol yields and the xylose consumption rates from a mixture of glucose and xylose with little xylitol accumulation. The engineered strain, however, still exhibited a long lag time when metabolizing xylose above 10 g/l as a sole carbon source, defined here as xylose toxicity. Through serial-subcultures on xylose, we isolated evolved strains which exhibited a shorter lag time and improved xylose-fermenting capabilities than the parental strain. Genome sequencing of the evolved strains revealed that mutations in PHO13 causing loss of the Pho13p function are associated with the improved phenotypes of the evolved strains. Crude extracts of a PHO13-overexpressing strain showed a higher phosphatase activity on xylulose-5-phosphate (X-5-P, suggesting that the dephosphorylation of X-5-P by Pho13p might generate a futile cycle with xylulokinase overexpression. While xylose consumption rates by the evolved strains improved substantially as compared to the parental strain, xylose metabolism was interrupted by accumulated acetate. Deletion of ALD6 coding for acetaldehyde dehydrogenase not only prevented acetate accumulation, but also enabled complete and efficient fermentation of xylose as well as a mixture of glucose and

Thermotolerant yeasts capable of producing bioethanol: isolation from natural fermented sources, identification and characterization

Directory of Open Access Journals (Sweden)

Ali Azam Talukder

2016-11-01

Full Text Available Recently, the demands of biofuels have increased, because of their significant role in reducing various pollutants created by fossil fuels. Here, we have collected 25 samples containing various thermotolerant microorganisms from the nine natural fermented sources of Bangladesh, such as Boiled potato (Bp, Decomposed foods (Df, Municipal liquid waste (Mlw, Municipal solid waste (Msw, Sugarcane juice (Sc, Pantavat (Pv, Sugar molasses (Sm, Tari (Tari and Watermelon juice (Wm for bioethanol production. Among them, 18 isolates are capable of producing bioethanol. Cultural, morphological, physiological, biochemical and genetic analyses were carried out under various physiological conditions. Ethanol fermentation was checked by different carbon sources, temperatures and pH. All of the isolates could grow well in the medium containing Dextrose and Arabinose and only two strains Pv-1 and Bp-2 could ferment Xylose as a sole carbon source. At 42 °C, the highest ethanol concentration 6.58% (v/v was obtained by a strain Wm-1 isolated from Watermelon juice. At 37 °C, maximal ethanol concentrations of 6.74% (v/v, 6.50% (v/v and 6.22% (v/v were obtained by the strains Bp-2, Wm-l and Pv-1, respectively. Among the various pH tested, the highest ethanol concentration 6.6% (v/v was obtained at pH 4.5 by a strain named Tari-2. Finally, yeast 26S rDNA sequencing information identified the strains Sc-2 as Saccharomyces cerevisiae Pv-2, Tari-2 and Df-1 as Pichia kudriavzevii, Mlw-l and Bp-2 as Candida tropicalis, Pv-1 as Pichia guilliermondii and Df-2 as Candida rugosa.

Intolerância à lactose: mudança de paradigmas com a biologia molecular Lactose intolerance: changing paradigms due to molecular biology

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Rejane Mattar

2010-01-01

Full Text Available Na maioria dos mamíferos a atividade da enzima lactase diminui na parede intestinal após o desmame, caracterizando a hipolactasia primária que provoca sintomas de intolerância à lactose. A intensidade dos sintomas de distensão, flatulência, dor abdominal e diarreia variam, dependendo da quantidade de lactose ingerida, e aumentam com o passar da idade. A hipolactasia é determinada geneticamente, porém uma mutação ocorreu para que fizesse parte da humanidade tolerar o leite na idade adulta. O diagnóstico é feito por teste de tolerância, empregando a lactose como desafio. Com a descoberta dos finlandeses do polimorfismo associado com a persistência da lactase, principalmente no norte da Europa, o exame genético passou a ser outra ferramenta diagnóstica mais confortável para o intolerante. No Brasil, 43% dos brancos e dos mulatos têm alelo de persistência da lactase, sendo a hipolactasia mais frequente entre os negros e japoneses. Entretanto, na prática clínica indivíduos com hipolactasia podem ser orientados a consumir alguns derivados do leite e alimentos contendo lactose sem apresentar sintomas de intolerância, enquanto que outros terão que fazer restrição de lactose na dieta.In most mammals, lactase activity declines on the intestinal wall after weaning, characterizing primary hypolactasia that provokes symptoms of lactose intolerance. The intensity of symptoms of distention, flatulence, abdominal pain and diarrhea varies, according to the amount of ingested lactose, and increases with age. Hypolactasia is genetically determined; nonetheless, a mutation occurred that had made a part of mankind tolerate milk in adulthood. Diagnosis is made by a tolerance test, using the lactose challenge. With the discovery made by the Finns of polymorphism associated with lactase persistence, mainly, in Northern Europe, the genetic test was incorporated as a more comfortable diagnostic tool for the intolerant. In Brazil, 43% of

75 FR 2551 - NIH Consensus Development Conference: Lactose Intolerance and Health; Notice

Science.gov (United States)

2010-01-15

... Conference: Lactose Intolerance and Health; Notice Notice is hereby given by the National Institutes of Health (NIH) of the ``NIH Consensus Development Conference: Lactose Intolerance and Health'' to be held... the public. Lactose intolerance is the inability to digest significant amounts of lactose, a sugar...

Enzymatic hydrolysis of lactose of whey permeate

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Karina Nascimento de Almeida

2015-09-01

Full Text Available The whey permeate is the residual of the concentration process of the whey proteins by ultrafiltration method. It contains important nutrients such as lactose, minerals and some proteins and lipids. It is without an ending industrial waste that causes serious damage to the environment. For its full use the lactose must be hydrolyzed to enable its consumption by intolerant people. The enzymatic hydrolysis by lactase (β-galactosidase of Kluyveromyces lactis yeast is a safe method that does not compromise the integrity of other nutrients, enabling further use of the permeate as a raw material. This study aimed to perform tests of enzymatic hydrolysis of lactose in whey permeate formulations in a concentration of 0.2%, 0.7% and 1% at 30, 60 and 90 minutes with pH 6.3 medium and 37 °C. The reactions were monitored by high performance liquid chromatography which showed that the enzyme concentration of 0.7% at time 30 minutes formulations became safe for consumption by lactose intolerant people, according to minimum levels established by law.

Lactose intolerance and cow's milk protein allergy

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Adriano Henrique do Nascimento RANGEL

2016-01-01

Full Text Available Abstract Adverse reactions to food intake have very diverse etiology and symptomatology. Regarding milk, its food allergy is presented as lactose intolerance, the sugar in milk, or allergy to milk protein. Despite having different symptomatology, confusions among allergic conditions to dairy and its mediators are common. Milk protein allergy originates from protein components present in milk, causing reactions to either the protein fractions in emulsion (caseins or in whey (milk albumin. The allergic reaction is type IV mediated by T lymphocytes. The allergic reaction produces severe cellular damage and it triggers physical, mental and emotional symptomatology that may vary in time, intensity and severity. Lactose intolerance is originated by total or partial absence of the enzyme that digests this disaccharide. Lactose intolerance can be primary or congenital and secondary; the former being more rare and severe, the latter being more common. Lactase deficiency can be diagnosed by symptoms associated with cramping and diarrhea. Thus, the objective of this study was to conduct a review of available literature on cow’s milk protein allergy and lactose intolerance.

The effect of lactose-in-saline infusion on packed cell volume ...

African Journals Online (AJOL)

STORAGESEVER

2008-06-03

Jun 3, 2008 ... concluded that lactose ameliorated anaemia, by inhibiting the sequestration of desialylated ..... lactose infusion further supports the conclusion that lactose played ... statistics. 3rd. Ed. Chapman and Hall, London, pp. 191-194.

Catabolite control of sugar metabolism in Streptococcus thermophilus

NARCIS (Netherlands)

Bogaard, van den P.T.C.

2002-01-01

Streptococcus thermophilus is used in many industrial dairy fermentations that require processing of milk at elevated temperatures. Its primary function is the rapid conversion of lactose to lactate while it also contributes to important sensory qualities. S.