Vitamin Producing Lactic Acid Bacteria as Complementary Treatments for Intestinal Inflammation.

Background: Current therapies for against inflammatory bowel disease (IBD) are sometimes limited by high costs, high toxicities and/or undesirable side effects, reasons for which new treatments are constantly being developed and studied. In this regards, an increasing mass of data has demonstrated that fecal transplantations and probiotic supplementations have shown promising effects and could be considered as adjunct IBD treatments to decrease some of the unwanted side effects caused by primary treatments. Furthermore, there is also mounting evidence that suggests that certain vitamins could provide antiinflammatory effects and it has been shown that certain strains of lactic acid bacteria (LAB), the most commonly used probiotic microorganisms, can produce biologically active forms of certain vitamins.

Evaluation of the effect of soymilk fermented by a riboflavin-producing Lactobacillus plantarum strain in a murine model of colitis.

Inflammatory bowel diseases (IBD) are idiopathic diseases of the gastrointestinal tract characterised by recurrent inflammation that require lifelong treatments. It has been shown that certain strains of lactic acid bacteria (LAB) can produce specific health-promoting compounds in foods or in the gastrointestinal tract that can in turn prevent and/or treat IBD. This study was designed to evaluate the possible therapeutic potential of soymilk fermented by the riboflavin-producing strain Lactobacillus plantarum CRL 2130 in a trinitrobenzene sulfonic induced colitis mouse model.

Bacteria as vitamin suppliers to their host: a gut microbiota perspective.

Food-related lactic acid bacteria (LAB) as well as human gut commensals such as bifidobacteria can de novo synthesize and supply vitamins. This is important since humans lack the biosynthetic capacity for most vitamins and these must thus be provided exogenously. Although vitamins are present in a variety of foods, deficiencies still occur, mainly due to malnutrition as a result of insufficient food intake and because of poor eating habits.

B-group vitamin production by lactic acid bacteria--current knowledge and potential applications.

Although most vitamins are present in a variety of foods, human vitamin deficiencies still occur in many countries, mainly because of malnutrition not only as a result of insufficient food intake but also because of unbalanced diets. Even though most lactic acid bacteria (LAB) are auxotrophic for several vitamins, it is now known that certain strains have the capability to synthesize water-soluble vitamins such as those included in the B-group (folates, riboflavin and vitamin B(12) amongst others). This review article will show the current knowledge of vitamin biosynthesis by LAB and show how the proper selection of starter cultures and probiotic strains could be useful in preventing clinical and subclinical vitamin deficiencies.

Risk assessment of genetically modified lactic acid bacteria using the concept of substantial equivalence.

The use of food-grade microorganisms such as lactic acid bacteria (LAB) is one of the most promising methods for delivering health promoting compounds. Since it is not always possible to obtain strains that have the ability to produce specific compounds naturally or that produce them in sufficient quantities to obtain physiological responses, genetic modifications can be performed to improve their output. The objective of this study was to evaluate if previously studied genetically modified LAB (GM-LAB), with proven in vivo beneficial effects, are just as safe as the progenitor strain from which they were derived.

Supplementation with engineered Lactococcus lactis improves the folate status in deficient rats.

Objective: The aim of this study was to establish the bioavailability of different folates produced by engineered Lactococcus lactis strains using a rodent depletion-repletion bioassay.

Methods: Rats were fed a folate-deficient diet, which produces a reversible subclinical folate deficiency, supplemented with different L. lactis cultures that were added as the only source of folate.

Aglycone production by Lactobacillus rhamnosus CRL981 during soymilk fermentation.

Lactobacillus rhamnosus CRL981 showed the highest levels of beta-glucosidase and was selected to characterize this enzyme system, among 63 strains of different Lactobacillus species. The maximum activity was obtained at pH 6.4 and 42 degrees C.

Ability of Lactobacillus fermentum to overcome host alpha-galactosidase deficiency, as evidenced by reduction of hydrogen excretion in rats consuming soya alpha-galacto-oligosaccharides.

Background: Soya and its derivatives represent nutritionally high quality food products whose major drawback is their high content of alpha-galacto-oligosaccharides. These are not digested in the small intestine due to the natural absence of tissular alpha-galactosidase in mammals. The passage of these carbohydrates to the large intestine makes them available for fermentation by gas-producing bacteria leading to intestinal flatulence.

A novel dairy product fermented with Propionibacterium freudenreichii improves the riboflavin status of deficient rats.

Objective: Riboflavin deficiency is common in many parts of the world, particularly in developing countries. The use of riboflavin-producing strains in the production of dairy products such as fermented milk, yogurt, and cheese is feasible and economically attractive because it would decrease the costs involved during conventional vitamin fortification and satisfy consumer demands for healthier foods. The present study in a rat bioassay assessed the response of administration of yogurt containing a riboflavin-producing strain of Propionibacterium freudenreichii on the riboflavin status of deficient rats.

Lactococcus lactis is capable of improving the riboflavin status in deficient rats.

Lactococcus lactis is a commonly used starter strain that can be converted from a vitamin B2 consumer into a vitamin B2 'factory' by over-expressing its riboflavin biosynthesis genes. The present study was conducted to assess in a rat bioassay the response of riboflavin produced by GM or native lactic acid bacteria (LAB). The riboflavin-producing strains were able to eliminate most physiological manifestations of ariboflavinosis such as stunted growth, elevated erythrocyte glutathione reductase activation coefficient values and hepatomegalia that were observed using a riboflavin depletion-repletion model.

Lactobacillus fermentum CRL 722 is able to deliver active alpha-galactosidase activity in the small intestine of rats.

alpha-galactooligosaccharides (alpha-GOS) found in legumes such as soybeans can cause gastrointestinal disorders since mammals lack alpha-galactosidase (alpha-Gal) in the small intestine which is necessary for their hydrolysis. Lactobacillus fermentum CRL 722 is a lactic acid bacterium (LAB) capable of degrading alpha-GOS due to its elevated alpha-Gal activity. When conventional rats were fed live L.

Reduction of non-digestible oligosaccharides in soymilk: application of engineered lactic acid bacteria that produce alpha-galactosidase.

Human consumption of soy-derived products has been limited by the presence of non-digestible oligosaccharides (NDO), such as the alpha-galactooligosaccharides raffinose and stachyose. Most mammals, including man, lack pancreatic alpha-galactosidase (alpha-Gal), which is necessary for the hydrolysis of these sugars. However, such NDO can be fermented by gas-producing microorganisms present in the cecum and large intestine, which in turn can induce flatulence and other gastrointestinal disorders in sensitive individuals.

Nutritional requirements of Lactobacillus delbrueckii subsp. lactis in a chemically defined medium.

This study was undertaken to determine the nutritional requirements of Lactobacillus delbrueckii subsp. lactis and to develop a minimal chemically defined medium that supports sustained growth of these microorganisms. The single-omission technique was applied to each component of complete chemically defined medium in order to determine the nutritional requirements.

Characterization of the melA locus for alpha-galactosidase in Lactobacillus plantarum.

Alpha-galactosides are abundant sugars in legumes such as soy. Because of the lack of alpha-galactosidase (alpha-Gal) in the digestive tract, humans are unable to digest these sugars, which consequently induce flatulence. To develop the consumption of the otherwise highly nutritional soy products, the use of exogenous alpha-Gal is promising.

Modulation of the cell-surface proteinase activity of thermophilic lactobacilli by the Peptide supply.

The proteolytic system of thermophilic lactobacilli is considered important for bacterial nutrition as well as for the formation of flavor and texture in fermented products. We investigated the influence of peptide content on the cell surface proteinase and intracellular aminopeptidase activities from seven thermophilic lactobacilli strains. The proteinase activities were remarkably reduced in cells grown in the peptide-rich medium MRS or in a chemically defined medium supplemented with Casitone compared with those found in a synthetic medium.

Glutamate uptake in Lactobacillus delbrueckii subsp. bulgaricus CNRZ 208 and its enhancement by a combination of Mn2+ and Mg2+.

Aims: To demonstrate the mechanism of glutamate uptake in the dairy strain Lactobacillus delbrueckii subsp. bulgaricus CNRZ 208, and to characterize key aspects of the system.

Methods And Results: Glutamate uptake proceeded via an active transport system requiring an exogenous source of energy.

Effect of galactose and glucose on the exopolysaccharide production and the activities of biosynthetic enzymes in Lactobacillus casei CRL 87.

Aims: The objective of this work was to study the influence of the sugar source on exopolysaccharide (EPS) production and the activities of the enzymes involved in the synthesis of sugar nucleotides in Lactobacillus casei CRL 87. The relationship between these enzymes and EPS formation was determined.

Methods And Results: The concentration of EPS was estimated by the phenol/sulphuric acid method while the chemical composition of purified EPS was investigated using gas-liquid chromatography.

Isolation and characterization of a slowly milk-coagulating variant of Lactobacillus helveticus deficient in purine biosynthesis.

A slowly milk-coagulating variant (Fmc(-)) of Lactobacillus helveticus CRL 1062, designated S1, was isolated and characterized. Strain S1 possessed all the known essential components required to utilize casein as a nitrogen source, which include functional proteinase and peptidase activities as well as functional amino acid, di- and tripeptide, and oligopeptide transport systems. The amino acid requirements of strain S1 were similar to those of the parental strain.

Nutritional requirements and nitrogen-dependent regulation of proteinase activity of Lactobacillus helveticus CRL 1062.

The nutritional requirements of Lactobacillus helveticus CRL 1062 were determined with a simplified chemically defined medium (SCDM) and compared with those of L. helveticus CRL 974 (ATCC 15009). Both strains were found to be prototrophic for alanine, glycine, asparagine, glutamine, and cysteine.

Characterization of natural isolates of Lactobacillus strains to be used as starter cultures in dairy fermentation.

The technological relevant characteristics of five homofermentative lactobacilli strains, isolated from natural fermented hard cheeses, were studied. Isolates CRL 581 and CRL 654, from Argentinian artesanal hard cheeses, and isolates CRL 1177, CRL 1178, and CRL 1179, from Italian Grana cheeses, were identified as Lactobacillus delbrueckii subsp. lactis and Lactobacillus helveticus, respectively, by physiological and biochemical tests, SDS-PAGE of whole-cell proteins and sequencing of the variable (V1) region of the 16S ribosomal DNA.

Starter culture activity in refrigerated fermented soymilk.

The refrigerated shelf life of soymilk fermented with single cultures of Lactobacillus fermentum, L. casei, Streptococcus salivarius subsp. thermophilus, and Bifidobacterium longum was evaluated.

L-glutamate transport in Lactobacillus helveticus.

An energy source (glucose or lactose) was required for the transport of L-glutamic acid by Lactobacillus helveticus. Mg(2+), K(+) and Li(+) increased its accumulation while Ca(2+) and Na(+) decreased it. It was inhibited by NaF, indicating that ATP may be involved in uptake.

Effectiveness of Soy Milk as Food Carrier for Lactobacillus Acidophilus.

Three mild-fermented milk beverages prepared from soy milk and cow's milk were compared for their ability to preserve the cell viability of Lactobacillus acidophilus during refrigerated storage, in associative growth with Lactobacilus casei and Streptococcus thermophilus . The highest survival rate was obtained by using soy milk as substrate. The presence of L.

Cheese industry development and research in Argentina.

Research and development projects concerning cheese industry in Argentina are described in this study. Regional strains of lactic acid bacteria were isolated from different ecological pockets and their taxonomic profiles were determined. Proteolytic and acid activity as well as diacetyl production were analyzed.

An Orange-Reddish Pigmentation in Roquefort Cheese.

The presence of an anomalous orange-reddish coloration in Roquefort cheese during its ripening period was studied. No pigmented colonies were isolated from milk, curd, or cheeses after pressing, but their presence in relatively large numbers was observed after salting (7 d) up to the end of the ripening process (90 d). About 37% of the strains isolated (32 in all) were orange-pigment producers in light as well as in the dark (type I), whereas about 25% produced an orange coloration only in the light (type II).