Sample records for aerobic bacteria lactic

  1. Lactic Acid Bacteria

    NSDL National Science Digital Library

    This on-line exercise is focused on lactic acid bacteria, a group of related bacteria that produce lactic acid as a result of carbohydrate fermentation. It includes a protocol for the enrichment of lactic acid bacteria from enriched samples (like yogurt, sauerkraut, decaying plant matter, and tooth plaque). Three parameters are measured: growth, culture diversity, and pH. The exercise also includes instructions for the isolation of some of these bacteria by using the streak-plate method.

  2. Effect of a preparation containing lactic fermentation bacteria on the hygienic status and aerobic stability of silages.

    PubMed

    Selwet, M

    2008-01-01

    The objective of this study was to determine the influence of biological silage additive (Bonsilage) on the hygiene quality and nutritive value of maize and grass-legume silages. The experiments were conducted on FAO 240 maize (Zea mays L.) and a mixture of italian ryegrass (Lolium multiflorum L.), 50% with alfalfa (Medicago media Pers.), 50%. Group 1 was a control and comprised silage without any additives, group 2 was ensiled with the addition of 4 cm3 kg(-1) biological silage additive. After 60 days of silage process individual silages were subjected to microbiological composition, and chemical analyses of silages were also determined. Similar analyses were repeated at day 7 following exposure to oxygen. The applied biological silage additive was found to reduce (P<0.05) numbers of Clostridium, Enterobacteriaceae, yeasts and mold fungi cells, and increase (P<0.05) the number of LAB (lactic acid bacteria) in comparison with the control in both silages. Chemical analysis of the maize silage showed that the biological additive caused an increase (P<0.05) in DM (dry matter), CP (crude protein), WSC (water soluble carbohydrates), LA (lactic acid), AA (acetic acid), ethanol, and a decrease (P<0.05) in the concentration of BA (butyric acid), N-NH3 and pH value in comparison with the control. Chemical analysis of silage samples from the grass-legume mixture showed that the additive caused an increase (P<0.05) in the content of DM, CP, WSC, LA and AA in comparison with the control. Samples of silage with the addition of an inoculant were characterized by a lower (P<0.05) content of BA, N-NH3, ethanol and pH value. The biological additive impoved the aerobic stability of silages in the aerobic phase. PMID:18540206

  3. Effect of applying lactic acid bacteria isolated from forage crops on fermentation characteristics and aerobic deterioration of silage.

    PubMed

    Cai, Y; Benno, Y; Ogawa, M; Kumai, S

    1999-03-01

    Two selected strains, Lactobacillus casei FG 1 and Lactobacillus plantarum FG 10 that were isolated from forage crops were used as additives at 1.0 x 10(5) cfu/g of fresh matter to alfalfa, Italian ryegrass, and sorghum, and their effect on fermentation characteristics and aerobic deterioration of silage was studied. The three silages treated with strains FG 1 or FG 10 were well preserved; had significantly lower pH values, butyric acid, propionic acid, and ammonia N concentrations, gas production, and dry matter losses; and had significantly higher contents of residual water-soluble carbohydrates and lactic acid than did the respective control silages. Yeast counts were high in all treated silages and increased rapidly during aerobic exposure. As a result, treated silages spoiled faster upon aerobic exposure than did the respective control silages. Most yeasts isolated from deteriorated silages showed high tolerance to lactic acid but low tolerance to butyric acid, and they were able to grow at low pH conditions and assimilate lactic acid. The results confirmed that L. casei and L. plantarum improved fermentation quality but did not inhibit the growth of silage yeast or aerobic deterioration of the silage. PMID:10194670

  4. Lactic acid bacteria of meat and meat products

    Microsoft Academic Search

    Aubrey F. Egan

    1983-01-01

    When the growth of aerobic spoilage bacteria is inhibited, lactic acid bacteria may become the dominant component of the microbial flora of meats. This occurs with cured meats and with meats packaged in films of low gas permeability. The presence of a flora of psychrotrophic lactic acid bacteria on vacuum-packaged fresh chilled meats usually ensures that shelf-life is maximal. When

  5. Aerobic Anoxygenic Phototrophic Bacteria

    PubMed Central

    Yurkov, Vladimir V.; Beatty, J. Thomas

    1998-01-01

    The aerobic anoxygenic phototrophic bacteria are a relatively recently discovered bacterial group. Although taxonomically and phylogenetically heterogeneous, these bacteria share the following distinguishing features: the presence of bacteriochlorophyll a incorporated into reaction center and light-harvesting complexes, low levels of the photosynthetic unit in cells, an abundance of carotenoids, a strong inhibition by light of bacteriochlorophyll synthesis, and the inability to grow photosynthetically under anaerobic conditions. Aerobic anoxygenic phototrophic bacteria are classified in two marine (Erythrobacter and Roseobacter) and six freshwater (Acidiphilium, Erythromicrobium, Erythromonas, Porphyrobacter, Roseococcus, and Sandaracinobacter) genera, which phylogenetically belong to the ?-1, ?-3, and ?-4 subclasses of the class Proteobacteria. Despite this phylogenetic information, the evolution and ancestry of their photosynthetic properties are unclear. We discuss several current proposals for the evolutionary origin of aerobic phototrophic bacteria. The closest phylogenetic relatives of aerobic phototrophic bacteria include facultatively anaerobic purple nonsulfur phototrophic bacteria. Since these two bacterial groups share many properties, yet have significant differences, we compare and contrast their physiology, with an emphasis on morphology and photosynthetic and other metabolic processes. PMID:9729607

  6. Heteropolysaccharides from lactic acid bacteria

    Microsoft Academic Search

    Luc De Vuyst; Bart Degeest

    1999-01-01

    Microbial exopolysaccharides are biothickeners that can be added to a wide variety of food products, where they serve as viscosifying, stabilizing, emulsifying or gelling agents. Numerous exopolysaccharides with different composition, size and structure are synthesized by lactic acid bacteria. The heteropolysaccharides from both mesophilic and thermophilic lactic acid bacteria have received renewed interest recently. Structural analysis combined with rheological studies

  7. Effect of Applying Lactic Acid Bacteria Isolated from Forage Crops on Fermentation Characteristics and Aerobic Deterioration of Silage

    Microsoft Academic Search

    Yimin Cai; Y. Benno; M. Ogawa; S. Kumai

    1999-01-01

    Two selected strains, Lactobacillus casei FG 1 and Lactobacillus plantarum FG 10 that were isolated from forage crops were used as additives at 1.0 × 105 cfu\\/g of fresh matter to alfalfa, Italian ryegrass, and sorghum, and their effect on fermentation charac- teristics and aerobic deterioration of silage was studied. The three silages treated with strains FG 1 or FG

  8. Biopreservation by lactic acid bacteria

    Microsoft Academic Search

    Michael E. Stiles

    1996-01-01

    Biopreservation refers to extended storage life and enhanced safety of foods using the natural microflora and (or) their antibacterial products. Lactic acid bacteria have a major potential for use in biopreservation because they are safe to consume and during storage they naturally dominate the microflora of many foods. In milk, brined vegetables, many cereal products and meats with added carbohydrate,

  9. Dry matter and nutritional losses during aerobic deterioration of corn and sorghum silages as influenced by different lactic acid bacteria inocula.

    PubMed

    Tabacco, E; Righi, F; Quarantelli, A; Borreani, G

    2011-03-01

    The economic damage that results from aerobic deterioration of silage is a significant problem for farm profitability and feed quality. This paper quantifies the dry matter (DM) and nutritional losses that occur during the exposure of corn and sorghum silages to air over 14 d and assesses the possibility of enhancing the aerobic stability of silages through inoculation with lactic acid bacteria (LAB). The trial was carried out in Northern Italy on corn (50% milk line) and grain sorghum (early dough stage) silages. The crops were ensiled in 30-L jars, without a LAB inoculant (C), with a Lactobacillus plantarum inoculum (LP), and with a Lactobacillus buchneri inoculum (LB; theoretical rate of 1 × 10(6) cfu/g of fresh forage). The pre-ensiled material, the silage at silo opening, and the aerobically exposed silage were analyzed for DM content, fermentative profiles, yeast and mold count, starch, crude protein, ash, fiber components, 24-h and 48-h DM digestibility and neutral detergent fiber (NDF) degradability. The yield and nutrient analysis data of the corn and sorghum silages were used as input for Milk2006 to estimate the total digestible nutrients, net energy of lactation, and milk production per Mg of DM. The DM fermentation and respiration losses were also calculated. The inocula influenced the in vitro NDF digestibility at 24h, the net energy for lactation (NE(L)), and the predicted milk yield per megagram of DM, whereas the length of time of air exposure influenced DM digestibility at 24 and 48 h, the NE(L), and the predicted milk yield per megagram of DM in the corn silages. The inocula only influenced the milk yield per megagram of DM and the air exposure affected the DM digestibility at 24h, the NE(L), and the milk yield per megagram of DM in the sorghum silages. The milk yield, after 14 d of air exposure, decreased to 1,442, 1,418, and 1,277 kg/Mg of DM for C, LB, and LP corn silages, respectively, compared with an average value of 1,568 kg of silage at opening. In the sorghum silages, the milk yield, after 14 d of air exposure, decreased to 1,226, 1,278, and 1,250 kg/Mg of DM for C, LB, and LP, respectively. When the estimated milk yield per megagram of harvested DM of corn and sorghum silage were related to mold count, it was shown that the loss of potential milk production occurred when the mold count exceeded 4 log cfu/g of silage, and it was almost halved when the mold count reached values greater than 8 log cfu/g of silage. Inoculation with L. buchneri, at a rate of 1 × 10(6) cfu/g of fresh forage, enhanced the stability of the silage after exposure to air, and, consequently, contributed to maintaining the nutritional value of the harvested forage over time, for air exposure up to 7 d. PMID:21338806

  10. Genetics of Lactic Acid Bacteria

    NASA Astrophysics Data System (ADS)

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

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

  11. Energy transduction in lactic acid bacteria

    Microsoft Academic Search

    Bert Poolman

    1993-01-01

    In the discovery of some general principles of energy transduction, lactic acid bacteria have played an important role. In this review, the energy transducing processes of lactic acid bacteria are discussed with the emphasis on the major developments of the past 5 years. This work not only includes the biochemistry of the enzymes and the bioenergetics of the processes, but

  12. Proteolytic systems in lactic acid bacteria

    Microsoft Academic Search

    Barry A. Law; Jens Kolstad; Pekka Varmanen; Bert Poolman I; Wil N. Konings

    1983-01-01

    The proteolytic systems of lactic acid bacteria are important as a means of making protein and peptide N available for growth and as part of the curing or maturation processes which give foods their characteristic rheological and organoleptic properties. The proteolytic systems of lactic acid bacteria are described in relation to their growth and their functions in protein-rich foods. Their

  13. Comparative genomics of the lactic acid bacteria

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  14. Identification of predominant lactic acid bacteria isolated from traditionally fermented vegetable products of the Eastern Himalayas

    Microsoft Academic Search

    Jyoti P. Tamang; Buddhiman Tamang; Ulrich Schillinger; Charles M. A. P. Franz; Michael Gores; Wilhelm H. Holzapfel

    2005-01-01

    Gundruk, sinki and khalpi are lactic-fermented vegetable products of Sikkim in India, and inziangsang is a fermented leafy vegetable product of Nagaland and Manipur in India. A total of 65 samples of gundruk (25), sinki (12), khalpi (25) and inziangsang (3) were analysed for microbial counts. The population of lactic acid bacteria (LAB) as well as aerobic mesophilic counts were

  15. Potentials of Exopolysaccharides from Lactic Acid Bacteria

    Microsoft Academic Search

    Seema Patel; Avishek Majumder; Arun Goyal

    Recent research in the area of importance of microbes has revealed the immense industrial potential of exopolysaccharides\\u000a and their derivative oligosaccharides from lactic acid bacteria. However, due to lack of adequate technological knowledge,\\u000a the exopolysaccharides have remained largely under exploited. In the present review, the enormous potentials of different\\u000a types of exopolysaccharides from lactic acid bacteria are described. This also

  16. Evolutionary Genomics of Lactic Acid Bacteria

    Microsoft Academic Search

    Kira S. Makarova; Eugene V. Koonin

    2007-01-01

    The lactic acid bacteria (LAB) might be the most numerous group of bacteria linked to humans. They are naturally asso- ciated with mucosal surfaces, particularly the gastrointestinal tract, and are also indigenous to food-related habitats, includ- ing plant (fruits, vegetables, and cereal grains), wine, milk, and meat environments (60, 61). The LAB include both important pathogens, e.g., several Streptococcus species,

  17. Comparative genomics of the lactic acid bacteria

    SciTech Connect

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

    2006-06-01

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

  18. Filamentous bacteria existence in aerobic granular reactors.

    PubMed

    Figueroa, M; Val Del Río, A; Campos, J L; Méndez, R; Mosquera-Corral, A

    2015-05-01

    Filamentous bacteria are associated to biomass settling problems in wastewater treatment plants. In systems based on aerobic granular biomass they have been proposed to contribute to the initial biomass aggregation process. However, their development on mature aerobic granular systems has not been sufficiently studied. In the present research work, filamentous bacteria were studied for the first time after long-term operation (up to 300 days) of aerobic granular systems. Chloroflexi and Sphaerotilus natans have been observed in a reactor fed with synthetic wastewater. These filamentous bacteria could only come from the inoculated sludge. Thiothrix and Chloroflexi bacteria were observed in aerobic granular biomass treating wastewater from a fish canning industry. Meganema perideroedes was detected in a reactor treating wastewater from a plant processing marine products. As a conclusion, the source of filamentous bacteria in these mature aerobic granular systems fed with industrial effluents was the incoming wastewater. PMID:25533039

  19. Evaluation of lactic acid bacteria autolysate for the supplementation of lactic acid bacteria fermentation

    Microsoft Academic Search

    A. Amrane

    2000-01-01

    At the end of culture in a carbon-limited medium, i.e. the best conditions for subsequent autolysis, lactic acid bacteria were harvested and autolysed at 50 °C for 24 h. The resulting supernatant was then successfully tested as a substitute for industrial yeast extract for the supplementation of whey permeate and its conversion into lactic acid: for almost equivalent total nitrogen

  20. Evolution, biodiversity, taxonomy Detection and identification of lactic acid bacteria

    E-print Network

    Paris-Sud XI, Université de

    Evolution, biodiversity, taxonomy Detection and identification of lactic acid bacteria in milk in milk or in an industrial medium. PNA / fluorescent in situ hybridization / lactic acid bacteria / r-organisms such as lactic acid bacteria directly in milk, starter culture or fermented food allows a better control

  1. Lactic acid bacteria in fish: a review

    Microsoft Academic Search

    Einar Ringø; François-Joël Gatesoupe

    1998-01-01

    Fish are continuously exposed to a wide range of microorganisms present in the environment, and the microbiota of fish have been the subject of several reviews. This review evaluates lactic acid bacteria in fish, and focuses on the several investigations that have demonstrated that Streptococcus, Leuconostoc, Lactobacillus, and Carnobacterium belong to the normal microbiota of the gastrointestinal tract in healthy

  2. Probiotic Spectra of Lactic Acid Bacteria (LAB)

    Microsoft Academic Search

    A. S. Naidu; W. R. Bidlack; R. A. Clemens

    1999-01-01

    Lactic acid bacteria (LAB) and their probio-active cellular substances exert many beneficial effects in the gastrointestinal tract. LAB prevent adherence, establishment, and replication of several enteric mucosal pathogens through several antimicrobial mechanisms. LAB also release various enzymes into the intestinal lumen and exert potential synergistic effects on digestion and alleviate symptoms of intestinal malabsoption. Consumption of LAB fermented dairy products

  3. The proteotytic systems of lactic acid bacteria

    Microsoft Academic Search

    Edmund R. S. Kunji; Igor Mierau; Anja Hagting; Bert Poolman; Wil N. Konings

    1996-01-01

    Proteolysis in dairy lactic acid bacteria has been studied in great detail by genetic, biochemical and ultrastructural methods. From these studies the picture emerges that the proteolytic systems of lactococci and lactobacilli are remarkably similar in their components and mode of action. The proteolytic system consists of an extracellularly located serine-proteinase, transport systems specific for di-tripeptides and oligopeptides (> 3

  4. Genetic transfer systems in lactic acid bacteria

    Microsoft Academic Search

    Michael J. Gasson

    1983-01-01

    Gene transfer processes (transfuction, conjugation, protoplast fusion mediated exchange, transformation in protoplasts) in lactic acid bacteria are reviewed in this paper. Besides, the detailed molecular nature of lactose plasmids in the Streptococcus lactis C2, 712 and ML3 strain complex is discussed.

  5. Discovering lactic acid bacteria by genomics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This review summarizes a collection of lactic acid bacteria that are now undergoing genomic sequencing and analysis. Summaries are presented on 20 different species, with each overview discussing the organisms fundamental and practical significance, environmental habitat, and its role in fermentati...

  6. Food phenolics and lactic acid bacteria

    Microsoft Academic Search

    Héctor Rodríguez; José Antonio Curiel; José María Landete; Blanca de las Rivas; Félix López de Felipe; Carmen Gómez-Cordovés; José Miguel Mancheño; Rosario Muñoz

    2009-01-01

    Phenolic compounds are important constituents of food products of plant origin. These compounds are directly related to sensory characteristics of foods such as flavour, astringency, and colour. In addition, the presence of phenolic compounds on the diet is beneficial to health due to their chemopreventive activities against carcinogenesis and mutagenesis, mainly due to their antioxidant activities. Lactic acid bacteria (LAB)

  7. Precision genome engineering in lactic acid bacteria.

    PubMed

    van Pijkeren, Jan Peter; Britton, Robert A

    2014-08-29

    Innovative new genome engineering technologies for manipulating chromosomes have appeared in the last decade. One of these technologies, recombination mediated genetic engineering (recombineering) allows for precision DNA engineering of chromosomes and plasmids in Escherichia coli. Single-stranded DNA recombineering (SSDR) allows for the generation of subtle mutations without the need for selection and without leaving behind any foreign DNA. In this review we discuss the application of SSDR technology in lactic acid bacteria, with an emphasis on key factors that were critical to move this technology from E. coli into Lactobacillus reuteri and Lactococcus lactis. We also provide a blueprint for how to proceed if one is attempting to establish SSDR technology in a lactic acid bacterium. The emergence of CRISPR-Cas technology in genome engineering and its potential application to enhancing SSDR in lactic acid bacteria is discussed. The ability to perform precision genome engineering in medically and industrially important lactic acid bacteria will allow for the genetic improvement of strains without compromising safety. PMID:25185700

  8. Precision genome engineering in lactic acid bacteria

    PubMed Central

    2014-01-01

    Innovative new genome engineering technologies for manipulating chromosomes have appeared in the last decade. One of these technologies, recombination mediated genetic engineering (recombineering) allows for precision DNA engineering of chromosomes and plasmids in Escherichia coli. Single-stranded DNA recombineering (SSDR) allows for the generation of subtle mutations without the need for selection and without leaving behind any foreign DNA. In this review we discuss the application of SSDR technology in lactic acid bacteria, with an emphasis on key factors that were critical to move this technology from E. coli into Lactobacillus reuteri and Lactococcus lactis. We also provide a blueprint for how to proceed if one is attempting to establish SSDR technology in a lactic acid bacterium. The emergence of CRISPR-Cas technology in genome engineering and its potential application to enhancing SSDR in lactic acid bacteria is discussed. The ability to perform precision genome engineering in medically and industrially important lactic acid bacteria will allow for the genetic improvement of strains without compromising safety. PMID:25185700

  9. Original article Antagonism of lactic acid bacteria towards

    E-print Network

    Paris-Sud XI, Université de

    Original article Antagonism of lactic acid bacteria towards Staphylococcus aureus and Escherichia 10 October 1994; accepted 22 May 1995) Summary ― The antagonistic effect of lactic acid INTRODUCTION Lactic acid bacteria (LAB), which are the normal flora of digestive and urogenital tracts (Watkins

  10. Carbohydrate metabolism in lactic acid bacteria

    Microsoft Academic Search

    Otto Kandler

    1983-01-01

    The term “lactic acid bacteria” is discussed. An overview of the following topics is given: main pathways of homo- and heterofermentation of hexoses, i.e. glycolysis, bifidus pathway, 6-phosphogluconate pathway; uptake and dissimilation of lactose (tagatose pathway); fermentation of pentoses and pentitols; alternative fates of pyruvate, i.e. splitting to formate and acetate, CO2 and acetate or formation of acetoin and diacetyl;

  11. Lactic acid bacteria production from whey

    Microsoft Academic Search

    María Elena Mondragón-Parada; Minerva Nájera-Martínez; Cleotilde Juárez-Ramírez; Juvencio Galíndez-Mayer; Nora Ruiz-Ordaz; Eliseo Cristiani-Urbina

    2006-01-01

    The main purpose of this work was to isolate and characterize lactic acid bacteria (LAB) strains to be used for biomass production\\u000a using a whey-based medium supplemented with an ammonium salt and with very low levels of yeast extract (0.25 g\\/L). Five strains\\u000a of LAB were isolated from naturally soured milk after enrichment in whey-based medium. One bacterial isolate, designated

  12. Biosynthesis of bacteriocins in lactic acid bacteria

    Microsoft Academic Search

    Ingolf F. Nes; Dzung Bao Diep; Leiv Sigve Håvarstein; May Bente Brurberg; Vincent Eijsink; Helge Holo

    1996-01-01

    A large number of new bacteriocins in lactic acid bacteria (LAB) has been characterized in recent years. Most of the new bacteriocins belong to the class II bacteriocins which are small (30–100 amino acids) heat-stable and commonly not post-translationally modified. While most bacteriocin producers synthesize only one bacteriocin, it has been shown that several LAB produce multiple bacteriocins (2–3 bacteriocins).

  13. Freeze-drying of lactic acid bacteria.

    PubMed

    Fonseca, Fernanda; Cenard, Stéphanie; Passot, Stéphanie

    2015-01-01

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

  14. Antagonism of Lactic Acid Bacteria against Phytopathogenic Bacteria

    PubMed Central

    Visser, Ronèl; Holzapfel, Wilhelm H.; Bezuidenhout, Johannes J.; Kotzé, Johannes M.

    1986-01-01

    A variety of lactic acid bacteria, isolated from plant surfaces and plant-associated products, were found to be antagonistic to test strains of the phytopathogens Xanthomonas campestris, Erwinia carotovora, and Pseudomonas syringae. Effective “in vitro” inhibition was found both on agar plates and in broth cultures. In pot trials, treatment of bean plants with a Lactobacillus plantarum strain before inoculation with P. syringae caused a significant reduction of the disease incidence. Images PMID:16347150

  15. Technological, phenotypic and genotypic characterisation of wild lactic acid bacteria involved

    E-print Network

    Paris-Sud XI, Université de

    Technological, phenotypic and genotypic characterisation of wild lactic acid bacteria involved of the research was to investigate the dynamics of wild lactic acid bacteria (LAB) involved in Bitto production Keywords Lactic acid bacteria . Raw milk cheese . Bitto . Technological characterization . Antimicrobial

  16. Lactic acid bacteria of foods and their current taxonomy

    Microsoft Academic Search

    Michael E. Stiles; Wilhelm H. Holzapfel

    1997-01-01

    Application of molecular genetic techniques to determine the relatedness of food-associated lactic acid bacteria has resulted in significant changes in their taxonomic classification. During the 1980s the genus Streptococcus was separated into the three genera Enterococcus, Lactococcus and Streptococcus. The lactic acid bacteria associated with foods now include species of the genera Carnobacterium, Enterococcus, Lactobacillus, Lactococcus, Leuconostoc, Oenococcus, Pediococcus, Streptococcus,

  17. Fermentation of Fructooligosaccharides by Lactic Acid Bacteria and Bifidobacteria

    Microsoft Academic Search

    Handan Kaplan; Robert W. Hutkins

    2000-01-01

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

  18. Towards lactic acid bacteria-based biorefineries.

    PubMed

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

    2014-11-15

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

  19. Exopolysaccharides from sourdough lactic acid bacteria.

    PubMed

    Galle, Sandra; Arendt, Elke K

    2014-01-01

    The use of sourdough improves the quality and increases the shelf life of bread. The positive effects are associated with metabolites produced by lactic acid bacteria (LAB) during sourdough fermentation, including organic acids, exopolysaccharides (EPS), and enzymes. EPS formed during sourdough fermentation by glycansucrase activity from sucrose influence the viscoelastic properties of the dough and beneficially affect the texture and shelf life (in particular, starch retrogradation) of bread. Accordingly, EPS have the potential to replace hydrocolloids currently used as bread improvers and meet so the consumer demands for a reduced use of food additives. In this review, the current knowledge about the functional aspects of EPS formation by sourdough LAB especially in baking applications is summarized. PMID:24499068

  20. Hydrogen Peroxide Formation and Catalase Activity in the Lactic Acid Bacteria

    Microsoft Academic Search

    R. Whittenbury

    1964-01-01

    SUMMARY Some lactic acid bacteria formed detectable H202 and some did not, regardless of their preference or requirement for aerobic or anaerobic conditions. Whether or not H202 was formed depended in some instances on the substrate used as energy source. Two H202-splitting activities were encountered though never in the same organism. One, named pseudo- catalase activity, was insensitive to 0.01

  1. Clinical importance of lactic acid bacteria: a short review.

    PubMed

    Kumari, Archana; Catanzaro, Roberto; Marotta, Francesco

    2011-12-01

    Lactic acid bacteria (LAB) were used extensively as starter cultures in food fermentation. Some of the health benefits which have been claimed for lactic acid bacteria as probiotics include the following: improvement of the normal microflora, prevention of infectious diseases and food allergies, reduction of serum cholesterol, anticarcinogenic activity, stabilization of the gut mucosal barrier, immune adjuvant properties, alleviation of intestinal bowel disease symptoms and improvement in the digestion of lactose in intolerant hosts. The present study is aimed to brief review the some clinical importance of lactic acid bacteria (www.actabiomedica.it). PMID:22783712

  2. Identification and functional properties of dominant lactic acid bacteria isolated at different stages of solid state fermentation of cassava during traditional gari production

    Microsoft Academic Search

    F. A. Oguntoyinbo

    2007-01-01

    Culture-based technique was used to study the population dynamics of the bacteria and determine the dominant lactic acid bacteria\\u000a (LAB) during cassava fermentation. LAB was consistently isolated from the fermented mash with an initial viable count of 6.00 log c.f.u. g?1 observed at 12 h. The aerobic viable count of amylolytic lactic acid bacteria (ALAB) was higher than other group of LAB throughout\\u000a the

  3. Fermentation of roselle juice by lactic acid bacteria

    Microsoft Academic Search

    Sukon Tantipaibulvut

    This research was conducted to determine the suitability of roselle calyces as a raw material for the production of probiotic roselle juice by lactic acid bacteria (Lactobacillus plantarum and Lactobacillus casei). The juice was fermented for 72 h at 30°C and 37°C separately and then analyzed for pH, acidity, sugar content and viable cell counts. Both lactic cultures were found

  4. Isolation, characterization and identification of lactic acid bacteria involved in traditional fermentation of borde, an Ethiopian cereal beverage

    Microsoft Academic Search

    Kebede Abegaz

    Changes in pH, titratable acidity, Enterobacteriaceae, aerobic mesophiles, lactic acid bacteria (LAB) and yeast counts were investigated during borde fermentation. A rapid decrease in pH was associated with accelerated growth rate of LAB and inhibition of Enterobacteriaceae. Wide diversities of LAB strains were present at early stage of borde fermentation. The number of species reduced as the fermentation progressed. Representatives

  5. Lactic acid bacteria from fermented table olives.

    PubMed

    Hurtado, Albert; Reguant, Cristina; Bordons, Albert; Rozès, Nicolas

    2012-08-01

    Table olives are one of the main fermented vegetables in the world. Olives can be processed as treated or natural. Both have to be fermented but treated green olives have to undergo an alkaline treatment before they are placed in brine to start their fermentation. It has been generally established that lactic acid bacteria (LAB) are responsible for the fermentation of treated olives. However, LAB and yeasts compete for the fermentation of natural olives. Yeasts play a minor role in some cases, contributing to the flavour and aroma of table olives and in LAB development. The main microbial genus isolated in table olives is Lactobacillus. Other genera of LAB have also been isolated but to a lesser extent. Lactobacillus plantarum and Lactobacillus pentosus are the predominant species in most fermentations. Factors influencing the correct development of fermentation and LAB, such as pH, temperature, the amount of NaCl, the polyphenol content or the availability of nutrients are also reviewed. Finally, current research topics on LAB from table olives are reviewed, such as using starters, methods of detection and identification of LAB, their production of bacteriocins, and the possibility of using table olives as probiotics. PMID:22475936

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  7. Importance of lactic acid bacteria in Asian fermented foods

    PubMed Central

    2011-01-01

    Lactic acid bacteria play important roles in various fermented foods in Asia. Besides being the main component in kimchi and other fermented foods, they are used to preserve edible food materials through fermentation of other raw-materials such as rice wine/beer, rice cakes, and fish by producing organic acids to control putrefactive microorganisms and pathogens. These bacteria also provide a selective environment favoring fermentative microorganisms and produce desirable flavors in various fermented foods. This paper discusses the role of lactic acid bacteria in various non-dairy fermented food products in Asia and their nutritional and physiological functions in the Asian diet. PMID:21995342

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

    PubMed

    Douillard, François P; de Vos, Willem M

    2014-08-29

    Genome analysis using next generation sequencing technologies has revolutionized the characterization of lactic acid bacteria and complete genomes of all major groups are now available. Comparative genomics has provided new insights into the natural and laboratory evolution of lactic acid bacteria and their environmental interactions. Moreover, functional genomics approaches have been used to understand the response of lactic acid bacteria to their environment. The results have been instrumental in understanding the adaptation of lactic acid bacteria in artisanal and industrial food fermentations as well as their interactions with the human host. Collectively, this has led to a detailed analysis of genes involved in colonization, persistence, interaction and signaling towards to the human host and its health. Finally, massive parallel genome re-sequencing has provided new opportunities in applied genomics, specifically in the characterization of novel non-GMO strains that have potential to be used in the food industry. Here, we provide an overview of the state of the art of these functional genomics approaches and their impact in understanding, applying and designing lactic acid bacteria for food and health. PMID:25186768

  9. Current research on the genetics of lactic acid production in lactic acid bacteria

    Microsoft Academic Search

    B. E. Davidson; R. M. Llanos; M. R. Cancilla; N. C. Redman; A. J. Hillier

    1995-01-01

    Lactic acid derived from lactose is a major by-product of energy production in lactic acid bacteria. The uptake of lactose by these organisms is mediated either by the lactose phosphoenolpyruvate-phosphotransferase system (lactose PEP-PTS), or by a lactose-proton symport system. The disaccharide is then converted to lactate with the concomitant production of ATP. In Lactococcus lactis the genes encoding the lactose

  10. Biology of Moderately Halophilic Aerobic Bacteria

    PubMed Central

    Ventosa, Antonio; Nieto, Joaquín J.; Oren, Aharon

    1998-01-01

    The moderately halophilic heterotrophic aerobic bacteria form a diverse group of microorganisms. The property of halophilism is widespread within the bacterial domain. Bacterial halophiles are abundant in environments such as salt lakes, saline soils, and salted food products. Most species keep their intracellular ionic concentrations at low levels while synthesizing or accumulating organic solutes to provide osmotic equilibrium of the cytoplasm with the surrounding medium. Complex mechanisms of adjustment of the intracellular environments and the properties of the cytoplasmic membrane enable rapid adaptation to changes in the salt concentration of the environment. Approaches to the study of genetic processes have recently been developed for several moderate halophiles, opening the way toward an understanding of haloadaptation at the molecular level. The new information obtained is also expected to contribute to the development of novel biotechnological uses for these organisms. PMID:9618450

  11. Fermentation Characteristics and Lactic Acid Bacteria Succession of Total Mixed Ration Silages Formulated with Peach Pomace

    PubMed Central

    Hu, Xiaodong; Hao, Wei; Wang, Huili; Ning, Tingting; Zheng, Mingli; Xu, Chuncheng

    2015-01-01

    The objective of this study was to assess the use of peach pomace in total mixed ration (TMR) silages and clarify the differences in aerobic stability between TMR and TMR silages caused by lactic acid bacteria (LAB). The TMR were prepared using peach pomace, alfalfa hay or Leymus chinensis hay, maize meal, soybean meal, cotton meal, limestone, a vitamin-mineral supplement, and salt in a ratio of 6.0:34.0:44.4:7.0:5.0:2.5:1.0:0.1 on a dry matter (DM) basis. Fermentation quality, microbial composition, and the predominant LAB were examined during ensiling and aerobic deterioration. The results indicated that the TMR silages with peach pomace were well fermented, with low pH and high lactic acid concentrations. The aerobic stability of TMR silages were significantly higher than that of TMR. Compared with TMR silages with alfalfa hay, TMR silage with Leymus chinensis hay was much more prone to deterioration. Although the dominant LAB were not identical in TMR, the same dominant species, Lactobacillus buchneri and Pediococcus acidilactici, were found in both types of TMR silages after 56 d of ensiling, and they may play an important role in the aerobic stability of TMR silages. PMID:25656205

  12. Fermentation characteristics and lactic Acid bacteria succession of total mixed ration silages formulated with peach pomace.

    PubMed

    Hu, Xiaodong; Hao, Wei; Wang, Huili; Ning, Tingting; Zheng, Mingli; Xu, Chuncheng

    2015-04-01

    The objective of this study was to assess the use of peach pomace in total mixed ration (TMR) silages and clarify the differences in aerobic stability between TMR and TMR silages caused by lactic acid bacteria (LAB). The TMR were prepared using peach pomace, alfalfa hay or Leymus chinensis hay, maize meal, soybean meal, cotton meal, limestone, a vitamin-mineral supplement, and salt in a ratio of 6.0:34.0:44.4:7.0:5.0:2.5:1.0:0.1 on a dry matter (DM) basis. Fermentation quality, microbial composition, and the predominant LAB were examined during ensiling and aerobic deterioration. The results indicated that the TMR silages with peach pomace were well fermented, with low pH and high lactic acid concentrations. The aerobic stability of TMR silages were significantly higher than that of TMR. Compared with TMR silages with alfalfa hay, TMR silage with Leymus chinensis hay was much more prone to deterioration. Although the dominant LAB were not identical in TMR, the same dominant species, Lactobacillus buchneri and Pediococcus acidilactici, were found in both types of TMR silages after 56 d of ensiling, and they may play an important role in the aerobic stability of TMR silages. PMID:25656205

  13. Degradation and biosynthesis of terpenoids by lactic acid bacteria isolated from cheese: first evidence

    E-print Network

    Paris-Sud XI, Université de

    NOTE Degradation and biosynthesis of terpenoids by lactic acid bacteria isolated from cheese: first.V. 2011 Abstract The aim of this study was to investigate whether lactic acid bacteria (LAB), isolated;Keywords Degradation . Biosynthesis . Terpenoids . Lactic acid bacteria . . . 1 Introduction Terpenes

  14. Symbionts as Major Modulators of Insect Health: Lactic Acid Bacteria and Honeybees

    E-print Network

    Paxton, Robert

    Symbionts as Major Modulators of Insect Health: Lactic Acid Bacteria and Honeybees Alejandra Va), Karolinska Institutet, Stockholm, Sweden Abstract Lactic acid bacteria (LAB) are well recognized beneficial Modulators of Insect Health: Lactic Acid Bacteria and Honeybees. PLoS ONE 7(3): e33188. doi:10.1371/journal

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

    Microsoft Academic Search

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

    2010-01-01

    Polyols are sugar alcohols largely used as sweeteners and they are claimed to have several health-promoting effects (low-caloric,\\u000a low-glycemic, low-insulinemic, anticariogenic, and prebiotic). While at present chemical synthesis is the only strategy able\\u000a to assure the polyol market demand, the biotechnological production of polyols has been implemented in yeasts, fungi, and\\u000a bacteria. Lactic acid bacteria (LAB) are a group of

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  17. Bacteriocins from Lactic Acid Bacteria: Production, Purification, and Food Applications

    Microsoft Academic Search

    Luc De Vuyst; Frédéric Leroy

    2007-01-01

    In fermented foods, lactic acid bacteria (LAB) display numerous antimicrobial activities. This is mainly due to the production of organic acids, but also of other compounds, such as bacteriocins and antifungal peptides. Several bacteriocins with industrial potential have been purified and characterized. The kinetics of bacteriocin production by LAB in relation to process factors have been studied in detail through

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  19. Taxonomy and physiology of probiotic lactic acid bacteria

    Microsoft Academic Search

    Günter Klein; Alexander Pack; Christine Bonaparte; Gerhard Reuter

    1998-01-01

    The current taxonomy of probiotic lactic acid bacteria is reviewed with special focus on the genera Lactobacillus, Bifidobacterium and Enterococcus. The physiology and taxonomic position of species and strains of these genera were investigated by phenotypic and genomic methods. In total, 176 strains, including the type strains, have been included. Phenotypic methods applied were based on biochemical, enzymatical and physiological

  20. Genetics of the proteolytic system of lactic acid bacteria

    Microsoft Academic Search

    Jan Kok

    1990-01-01

    The proteolytic system of lactic acid bacteria is of eminent importance for the rapid growth of these organisms in protein-rich media. The combined action of proteinases and peptidases provides the cell with small peptides and essential amino acids. The amino acids and peptides thus liberated have to be translocated across the cytoplasmic membrane. To that purpose, the cell contains specific

  1. Peptidases and amino acid catabolism in lactic acid bacteria

    Microsoft Academic Search

    Jeffrey E. Christensen; Edward G. Dudley; Jeffrey A. Pederson; James L. Steele

    1999-01-01

    The conversion of peptides to free amino acids and their subsequent utilization is a central metabolic activity in prokaryotes. At least 16 peptidases from lactic acid bacteria (LAB) have been characterized biochemically and\\/or genetically. Among LAB, the peptidase systems of Lactobacillus helveticus and Lactococcus lactis have been examined in greatest detail. While there are homologous enzymes common to both systems,

  2. Lactic acid bacteria in fermented foods in Thailand

    Microsoft Academic Search

    S. Tanasupawat; K. Komagata

    1995-01-01

    Traditional fermented foods (fish, meat and vegetable products), produced by many different processes, are eaten in many parts of Thailand. Lactic acid bacteria are responsible for the souring and ripening of these foods. Homofermentative strains of Lactobacillus pentosus, L. plantarum and Pediococcus pentosaceus are dominant in foods with low salt concentrations whereas P. halophilus strains are present in foods containing

  3. The Effect of Lactose Derivatives on Intestinal Lactic Acid Bacteria

    Microsoft Academic Search

    P. Kontula; M.-L. Suihko; A. Von Wright; T. Mattila-Sandholm

    1999-01-01

    Nine strains of lactic acid bacteria were studied for growth and fermentation end products on lactulose, lactitol, and lactobionic acid. In addition, human fecal and biopsy isolates were screened for new potential by probiotic strains utilizing lactose derivatives, and one new isolate of Lactobacillus rhamnosus was enriched. The utilization of lactose derivatives and the effect on the fermentation end products

  4. Modelling strategies for the industrial exploitation of lactic acid bacteria

    Microsoft Academic Search

    Eddy J. Smid; Bas Teusink

    2006-01-01

    Lactic acid bacteria (LAB) have a long tradition of use in the food industry, and the number and diversity of their applications has increased considerably over the years. Traditionally, process optimization for these applications involved both strain selection and trial and error. More recently, metabolic engineering has emerged as a discipline that focuses on the rational improvement of industrially useful

  5. Systems solutions by lactic acid bacteria: from paradigms to practice

    PubMed Central

    2011-01-01

    Lactic acid bacteria are among the powerhouses of the food industry, colonize the surfaces of plants and animals, and contribute to our health and well-being. The genomic characterization of LAB has rocketed and presently over 100 complete or nearly complete genomes are available, many of which serve as scientific paradigms. Moreover, functional and comparative metagenomic studies are taking off and provide a wealth of insight in the activity of lactic acid bacteria used in a variety of applications, ranging from starters in complex fermentations to their marketing as probiotics. In this new era of high throughput analysis, biology has become big science. Hence, there is a need to systematically store the generated information, apply this in an intelligent way, and provide modalities for constructing self-learning systems that can be used for future improvements. This review addresses these systems solutions with a state of the art overview of the present paradigms that relate to the use of lactic acid bacteria in industrial applications. Moreover, an outlook is presented of the future developments that include the transition into practice as well as the use of lactic acid bacteria in synthetic biology and other next generation applications. PMID:21995776

  6. Malolactic activity of lactic acid bacteria during sauerkraut fermentation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The frequency of lactic acid bacteria (LAB) involved in sauerkraut fermentation with (MDC+) or without (MDC-) the ability to decarboxylate malic acid was determined. The MDC+ phenotype was found in >99% of homofermentative LAB isolated from commercial fermentations. In contrast, heterofermentative...

  7. Selection of tropical lactic acid bacteria for enhancing the quality of maize silage.

    PubMed

    Santos, A O; Ávila, C L S; Schwan, R F

    2013-12-01

    The objective of this study was to select lactic acid bacteria (LAB) strains isolated from silage and assess their effect on the quality of maize silage. The LAB strains were inoculated into aqueous extract obtained from maize to evaluate their production of metabolites and pH reduction. The ability to inhibit the pathogenic and silage-spoilage microorganisms' growth was evaluated. Nine LAB strains that showed the best results were assessed in polyvinyl chloride experimental silos. The inoculation of the LAB strains influenced the concentration of lactic and acetic acids and the diversity of Listeria. The inoculation of silages with Lactobacillus buchneri (UFLA SLM11 and UFLA SLM103 strains) resulted in silages with greater LAB populations and improvements after aerobic exposure. The UFLA SLM11 and SLM103 strains identified as L. buchneri showed to be promising in the treatment of maize silage. PMID:24119815

  8. Effect of lactic acid bacteria on diarrheal diseases.

    PubMed

    Heyman, M

    2000-04-01

    Microbial balance is an important factor in the maintenance of intestinal homeostasis, and yogurt or fermented milk supplementation has been proposed to control diarrheal diseases. A number of studies using animal models and clinical studies in humans have confirmed the beneficial effect of such fermented products in case of lactose intolerance, viral diarrhea or antibiotics-associated diarrhea. The mechanisms by which lactic acid bacteria exert their effects are multiple. Bacterial lactase improves the absorption of lactose, but fermented products slow down the intestinal transit facilitating the action of residual intestinal lactase. The transient passage of lactic acid bacteria in the digestive tract may represent a microbial barrier against the development of pathogenic bacteria, probably due to the release of compounds contributing to the maintenance of colonization resistance to pathogens. The beneficial effects are mainly described in the presence of live bacteria, but inactivated bacteria may also present preventive or curative capacities in diarrheal diseases. Moreover, lactic acid bacteria has been described as reinforcing the non-specific immune defence but also specific immunity, particularly the secretory immune system mediated by secretory IgA or IgM in response to particulate infectious antigens and perhaps to soluble food antigens. Other possible mechanisms include the trophic effect on the intestinal layer, and a down-regulatory activity in cow's milk allergy as well as anti-inflammatory effects have also been suggested. PMID:10759139

  9. Lactic acid bacteria in the quality improvement and depreciation of wine

    Microsoft Academic Search

    Aline Lonvaud-Funel

    1999-01-01

    The winemaking process includes two main steps: lactic acid bacteria are responsible for the malolactic fermentation which follows the alcoholic fermentation by yeasts. Both types of microorganisms are present on grapes and on cellar equipment. Yeasts are better adapted to growth in grape must than lactic acid bacteria, so the alcoholic fermentation starts quickly. In must, up to ten lactic

  10. Predominant lactic acid bacteria in traditional fermented yak milk products in the Sichuan Province

    E-print Network

    Boyer, Edmond

    NOTE Predominant lactic acid bacteria in traditional fermented yak milk products in the Sichuan from widely distributed households in Sichuan province, China. In total, 213 strains of lactic acid.2%) ,, Keywords Yak milk products . Lactic acid bacteria . Isolation . Identification . 16S rDNA . Species

  11. The effect of bacteria, enzymes and inulin on fermentation and aerobic stability of corn silage

    PubMed Central

    Peymanfar, S; Kermanshahi, RK

    2012-01-01

    Background and Objectives Ensiling is a conservation method for forage crops. It is based on the fact that anaerobe lactic acid bacteria (LAB) convert watersoluble carbohydrates into organic acids. Therefore, pH decreases and the forage is preserved. The aim of this study was to isolate special kinds of lactic acid bacteria from silage and to study the effect of bacteria, inulin and enzymes as silage additives on the fermentation and aerobic stability of the silage. Materials and Methods The heterofermentative LAB were isolated from corn silages in Broujerd, Iran and biochemically characterized. Acid tolerance was studied by exposure to acidic PBS and growth in bile salt was measured by the spectrophotometric method. Results The results of molecular analysis using 16SrDNA sequences showed that the isolates belonged to Lactobacillus and Enterococcus genera. To enhance stability in acidic environment and against bile salts, microencapsulation with Alginate and Chitosan was used. The Lactobacillus plantarum strains were used as control. The inoculants (1 × 107 cfu/g) alone or in combination with inulin or in combination with enzymes were added to chopped forages and ensiled in 1.5-L anaerobic jars. Conclusion Combination of the isolates Lactobacillus and Enterococcus with inulin and enzymes can improve the aerobic stability of corn silage. PMID:23205249

  12. Quorum sensing-controlled gene expression in lactic acid bacteria

    Microsoft Academic Search

    Oscar P. Kuipers; Michiel Kleerebezem; Willem M. de Vos

    1998-01-01

    Quorum sensing in lactic acid bacteria (LAB) involves peptides that are directly sensed by membrane-located histidine kinases, after which the signal is transmitted to an intracellular response regulator. This regulator in turn activates transcription of target genes, that commonly include the structural gene for the inducer molecule. The two-component signal-transduction machinery has proven to be indispensable for transcription activation and

  13. Adaptation of lactic acid bacteria to unfavorable growth conditions

    Microsoft Academic Search

    N. A. Golod; N. G. Loiko; A. L. Mulyukin; A. L. Neiymatov; L. I. Vorobjeva; N. E. Suzina; E. F. Shanenko; V. F. Gal’chenko; G. I. El-Registan

    2009-01-01

    The adaptation of lactic acid bacteria (LAB) to unfavorable growth conditions, e.g., depletion of nutrient sources, overthreshold\\u000a cell density of a population, or antibiotic impact, was shown to include: (1) formation of cyst-like dormant cells (CDC) providing\\u000a for survival and species preservation and (2) realization of intra-population phenotypic variability, which is demonstrated\\u000a by development of non-dominant colonies on plates inoculated

  14. Fermentation of pomegranate juice by probiotic lactic acid bacteria

    Microsoft Academic Search

    Z. E. Mousavi; S. M. Mousavi; S. H. Razavi; Z. Emam-Djomeh; H. Kiani

    2011-01-01

    In this research, production of probiotic pomegranate juice through its fermentation by four strains of lactic acid bacteria:\\u000a Lactobacillus plantarum, L. delbruekii, L. paracasei, L. acidophilus was examined. Fermentation was carried out at 30°C for 72 h under microaerophilic conditions. Microbial population, pH, titrable\\u000a acidity, sugar and organic acid metabolism were measured during the fermentation period and the viability of all

  15. Contribution of lactic acid bacteria to flavour compound formation in dairy products

    Microsoft Academic Search

    G. Urbach

    1995-01-01

    Cheese flavour cannot be produced without starter bacteria. Lactic acid bacteria convert lactose to lactic acid and this together with their production of diacetyl and acetaldehyde are their main contributions to the flavour of cultured milks and fresh cheeses. In matured cheeses, the starter bacteria die out quickly and the rate at which they lyse and release their enzymes into

  16. Lactic acid bacteria with health claims—interactions and interference with gastrointestinal flora

    Microsoft Academic Search

    Tiina Mattila-Sandholm; Jaana Mättö; Maria Saarela

    1999-01-01

    Lactic acid bacteria in foods have a long history of safe use. Members of the genera Lactococcus and Lactobacillus have a ‘generally-recognised-as-safe’ status, whilst members of the genera Streptococcus and Enterococcus and some other genera of lactic acid bacteria contain opportunistic pathogens. New species and more specific strains of probiotic bacteria are constantly being identified. Prior to incorporating new strains

  17. Citric acid metabolism in hetero- and homofermentative lactic acid bacteria.

    PubMed Central

    Drinan, D F; Robin, S; Cogan, T M

    1976-01-01

    The effect of citrate on production of diacetyl and acetoin by four strains each of heterofermentative and homofermentative lactic acid bacteria capable of utilizing citrate was studied. Acetoin was quantitatively the more important compound. The heterofermentative bacteria produced no acetoin or diacetyl in the absence of citrate, and two strains produced traces of acetoin in its presence. Citrate stimulated the growth rate of the heterofermentative lactobacilli. Acidification of all heterofermentative cultures with citric acid resulted in acetoin production. Destruction of accumulated acetoin appeared to coincide with the disappearance of citrate. All homofermentative bacteria produced more acetoin and diacetyl in the presence of citrate than in its absence. Citrate utilization was begun immediately by the streptococci but was delayed until at least the middle of the exponential phase in the case of the lactobacilli. PMID:5054

  18. AEROBIC SALIVARY BACTERIA IN WILD AND CAPTIVE KOMODO DRAGONS

    Microsoft Academic Search

    Joel M. Montgomery; Don Gillespie; Putra Sastrawan; Terry M. Fredeking; George L. Stewart

    2002-01-01

    During the months of November 1996, August 1997, and March 1998, saliva and plasma samples were collected for isolation of aerobic bacteria from 26 wild and 13 captive Komodo dragons (Varanus komodoensis). Twenty-eight Gram-negative and 29 Gram-positive spe- cies of bacteria were isolated from the saliva of the 39 Komodo dragons. A greater number of wild than captive dragons were

  19. Flow Cytometric Assessment of Viability of Lactic Acid Bacteria

    PubMed Central

    Bunthof, Christine J.; Bloemen, Karen; Breeuwer, Pieter; Rombouts, Frank M.; Abee, Tjakko

    2001-01-01

    The viability of lactic acid bacteria is crucial for their applications as dairy starters and as probiotics. We investigated the usefulness of flow cytometry (FCM) for viability assessment of lactic acid bacteria. The esterase substrate carboxyfluorescein diacetate (cFDA) and the dye exclusion DNA binding probes propidium iodide (PI) and TOTO-1 were tested for live/dead discrimination using a Lactococcus, a Streptococcus, three Lactobacillus, two Leuconostoc, an Enterococcus, and a Pediococcus species. Plate count experiments were performed to validate the results of the FCM assays. The results showed that cFDA was an accurate stain for live cells; in exponential-phase cultures almost all cells were labeled, while 70°C heat-killed cultures were left unstained. PI did not give clear live/dead discrimination for some of the species. TOTO-1, on the other hand, gave clear discrimination between live and dead cells. The combination of cFDA and TOTO-1 gave the best results. Well-separated subpopulations of live and dead cells could be detected with FCM. Cell sorting of the subpopulations and subsequent plating on agar medium provided direct evidence that cFDA labels the culturable subpopulation and that TOTO-1 labels the nonculturable subpopulation. Applied to cultures exposed to deconjugated bile salts or to acid, cFDA and TOTO-1 proved to be accurate indicators of culturability. Our experiments with lactic acid bacteria demonstrated that the combination of cFDA and TOTO-1 makes an excellent live/dead assay with versatile applications. PMID:11319119

  20. Production, recovery and purification of bacteriocins from lactic acid bacteria

    Microsoft Academic Search

    E. Parente; A. Ricciardi

    1999-01-01

    Bacteriocins produced by lactic acid bacteria are a heterogeneous group of peptide inhibitors which include lantibiotics\\u000a (class I, e.g. nisin), small heat-stable peptides (class II, e.g. pediocin AcH\\/PA1) and large heat-labile proteins (class\\u000a III, e.g. helveticin J). Many bacteriocins belonging to the first two groups can be successfully used to inhibit undesirable\\u000a microorganisms in foods, but only nisin is produced

  1. Degradation of fructans by epiphytic and inoculated lactic acid bacteria during ensilage of normal and sterile ryegrass

    E-print Network

    Paris-Sud XI, Université de

    Degradation of fructans by epiphytic and inoculated lactic acid bacteria during ensilage of normal is readily available for fermentation in the silo by lactic acid bacteria (LAB) and other silage bacteria of whether microbial fructan hydrolase activity, particularly in lactic acid bacteria, is a prerequisite

  2. Functional fermented whey-based beverage using lactic acid bacteria.

    PubMed

    Pescuma, Micaela; Hébert, Elvira María; Mozzi, Fernanda; de Valdez, Graciela Font

    2010-06-30

    Whey protein concentrate (WPC) is employed as functional food ingredient because of its nutritional value and emulsifying properties. However, the major whey protein beta-lactoglobulin (BLG) is the main cause of milk allergy. The aim of this study was to formulate a fermented whey beverage using selected lactic acid bacteria and WPC35 (WPC containing 35% of proteins) to obtain a fermented product with low lactose and BLG contents and high essential amino acid concentration. Cell viability, lactose consumption, lactic acid production, proteolytic activity, amino acid release and BLG degradation by the selected strains Lactobacillus acidophilus CRL 636, Lactobacillus delbrueckii subsp. bulgaricus CRL 656 and Streptococcus thermophilus CRL 804, as single or mixed (SLaB) cultures were evaluated in WPC35 (10%, w/v) incubated at 37 degrees C for 24h. Then, the fermented WPC35 was mixed with peach juice and calcium lactate (2%, w/v) and stored at 10 degrees C for 28 days. During fermentation, single cultures grew 1.7-3.1 log CFU/ml and produced 25.1-95.0 mmol/l of lactic acid as consequence of lactose consumption (14.0-41.8 mmol/l) after 12h fermentation. L. delbrueckii subsp. bulgaricus CRL 656 was the most proteolytic strain (626 microg/ml Leu) and released the branched-chain essential amino acids Leu (16 microg/ml), Ile (27 microg/ml) and Val (43 microg/ml). All strains were able to degrade BLG in a range of 41-85% after 12h incubation. The starter culture SLaB grew 3.0 log CFU/ml, showed marked pH reduction, produced 122.0 mmol/l of lactic acid, displayed high proteolytic activity (484 microg/ml Leu) releasing Leu (13 microg/ml), Ile (18 microg/ml) and Val (35 microg/ml), and hydrolyzed 92% of BLG. The addition of calcium lactate to WPC35 maintained the drink pH stable during shelf life; no contamination was detected during this period. After 28 days, a decrease in cell viability of all strains was observed being more pronounced for L. delbrueckii subsp. bulgaricus CRL 656 and L. acidophilus CRL 636 (2.3 and 1.9 log CFU/ml, respectively). The results showed that WPC fermentation by rationally selected lactic acid bacteria might be used for developing functional beverages with improved characteristics such as reduced BLG content and increased branched-chain essential amino acids. PMID:20483186

  3. Current taxonomy of phages infecting lactic acid bacteria

    PubMed Central

    Mahony, Jennifer; van Sinderen, Douwe

    2013-01-01

    Phages infecting lactic acid bacteria have been the focus of significant research attention over the past three decades. Through the isolation and characterization of hundreds of phage isolates, it has been possible to classify phages of the dairy starter and adjunct bacteria Lactococus lactis, Streptococcus thermophilus, Leuconostoc spp., and Lactobacillus spp. Among these, phages of L. lactis have been most thoroughly scrutinized and serve as an excellent model system to address issues that arise when attempting taxonomic classification of phages infecting other LAB species. Here, we present an overview of the current taxonomy of phages infecting LAB genera of industrial significance, the methods employed in these taxonomic efforts and how these may be employed for the taxonomy of phages of currently underrepresented and emerging phage species. PMID:24478767

  4. Lactic Acid Bacteria Enriched from Human Gastric Biopsies

    PubMed Central

    Hakalehto, Elias; Vilpponen-Salmela, Terttu; Kinnunen, Kristiina; von Wright, Atte

    2011-01-01

    The purpose of this paper was to check if viable bacteria, in particular lactic acid bacteria (LAB), could be enriched from biopsies obtained from healthy gastroscopy patients. Gastric biopsies were obtained from 13 gastroscopy patients and subjected to an anaerobic or microaerophilic enrichment procedure utilizing the Portable Microbe Enrichment Unit (PMEU). Profuse microbial growth was observed in most cases. Samples plated on MRS showed high numbers of LAB. The most common species characterized were Lactobacillus reuteri, Lact. salivarius, and Streptococcus salivarius. The results demonstrate a continuous presence of viable LAB in healthy stomach. The species are similar to those traditionally used in food applications. The gastric LAB strains could have a potential in developing probiotic foods aimed specially on the upper part of the gastrointestinal tract. PMID:21991494

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

    PubMed Central

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

    2014-01-01

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

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

    PubMed

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

    2014-05-01

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

  7. Assessment of antibiotic resistance of lactic acid bacteria in Chinese fermented foods

    Microsoft Academic Search

    Lu Pan; Xiaoqing Hu; Xiaoyuan Wang

    2011-01-01

    Lactic acid bacteria isolated from 11 Chinese fermented foods were investigated for their resistance incidences of 7 clinically important antibiotics, including chloramphenicol, kanamycin, tetracycline, ciprofloxacin, ampicillin, clindamicin and erythromycin. It was found that antibiotic resistant lactic acid bacteria are widespread among traditional Chinese fermented foods and their resistance incidences depended on the raw material and manufacturing area of the foods.

  8. Comparison of Lactic Acid Bacteria Fermentation with Acid Treatments for Chitosan Production from Shrimp Waste

    Microsoft Academic Search

    Sureerat Phuvasate; Yi-Cheng Su

    2010-01-01

    The traditional procedure for chitosan production involves use of a strong acid (HCl) for demineralization of chitin. This study reports application of a mixed culture of lactic acid bacteria (Lactobacillus plantarum, Lactobacillus acidophilus, and Lactobacillus lactis) fermentation in demineralization of chitin for chitosan production from shrimp waste. Chitosan produced from shrimp waste with lactic acid bacteria fermentation at 30°C for

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

    Microsoft Academic Search

    M. I. Pastink

    2009-01-01

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

  10. Genomic reconstruction of transcriptional regulatory networks in lactic acid bacteria

    PubMed Central

    2013-01-01

    Background Genome scale annotation of regulatory interactions and reconstruction of regulatory networks are the crucial problems in bacterial genomics. The Lactobacillales order of bacteria collates various microorganisms having a large economic impact, including both human and animal pathogens and strains used in the food industry. Nonetheless, no systematic genome-wide analysis of transcriptional regulation has been previously made for this taxonomic group. Results A comparative genomics approach was used for reconstruction of transcriptional regulatory networks in 30 selected genomes of lactic acid bacteria. The inferred networks comprise regulons for 102 orthologous transcription factors (TFs), including 47 novel regulons for previously uncharacterized TFs. Numerous differences between regulatory networks of the Streptococcaceae and Lactobacillaceae groups were described on several levels. The two groups are characterized by substantially different sets of TFs encoded in their genomes. Content of the inferred regulons and structure of their cognate TF binding motifs differ for many orthologous TFs between the two groups. Multiple cases of non-orthologous displacements of TFs that control specific metabolic pathways were reported. Conclusions The reconstructed regulatory networks substantially expand the existing knowledge of transcriptional regulation in lactic acid bacteria. In each of 30 studied genomes the obtained regulatory network contains on average 36 TFs and 250 target genes that are mostly involved in carbohydrate metabolism, stress response, metal homeostasis and amino acids biosynthesis. The inferred networks can be used for genetic experiments, functional annotations of genes, metabolic reconstruction and evolutionary analysis. All reconstructed regulons are captured within the Streptococcaceae and Lactobacillaceae collections in the RegPrecise database (http://regprecise.lbl.gov). PMID:23398941

  11. Halophilic and Haloalkaliphilic, Aerobic Endospore-forming Bacteria in Soil

    Microsoft Academic Search

    M. Carmen Márquez; Cristina Sánchez-Porro; Antonio Ventosa

    \\u000a This chapter reviews the aerobic, endospore-forming moderately halophilic and haloalkaliphilic (and some halotolerant) bacteria\\u000a that have been reported to be isolated from saline soils or sediment samples. These species belong to the family Bacillaceae, within the phylum Firmicutes, and are included in the following genera: Alkalibacillus, Bacillus, Filobacillus, Gracilibacillus, Halalkalibacillus, Halobacillus, Lentibacillus, Ornithinibacillus, Paraliobacillus, Salirhabdus, Salsuginibacillus, Tenuibacillus, Terribacillus, Thalassobacillus and

  12. Aerobic and Anaerobic Starvation Metabolism in Methanotrophic Bacteria

    PubMed Central

    Roslev, P.; King, G. M.

    1995-01-01

    The capacity for anaerobic metabolism of endogenous and selected exogenous substrates in carbon- and energy-starved methanotrophic bacteria was examined. The methanotrophic isolate strain WP 12 survived extended starvation under anoxic conditions while metabolizing 10-fold less endogenous substrate than did parallel cultures starved under oxic conditions. During aerobic starvation, the cell biomass decreased by 25% and protein and lipids were the preferred endogenous substrates. Aerobic protein degradation (24% of total protein) took place almost exclusively during the initial 24 h of starvation. Metabolized carbon was recovered mainly as CO(inf2) during aerobic starvation. In contrast, cell biomass decreased by only 2.4% during anaerobic starvation, and metabolized carbon was recovered mainly as organic solutes in the starvation medium. During anaerobic starvation, only the concentration of intracellular low-molecular-weight compounds decreased, whereas no significant changes were measured for cellular protein, lipids, polysaccharides, and nucleic acids. Strain WP 12 was also capable of a limited anaerobic glucose metabolism in the absence of added electron acceptors. Small amounts of CO(inf2) and organic acids, including acetate, were produced from exogenous glucose under anoxic conditions. Addition of potential anaerobic electron acceptors (fumarate, nitrate, nitrite, or sulfate) to starved cultures of the methanotrophs Methylobacter albus BG8, Methylosinus trichosporium OB3b, and strain WP 12 did not stimulate anaerobic survival. However, anaerobic starvation of these bacteria generally resulted in better survival than did aerobic starvation. The results suggest that methanotrophic bacteria can enter a state of anaerobic dormancy accompanied by a severe attenuation of endogenous metabolism. In this state, maintenance requirements are presumably provided for by fermentation of certain endogenous substrates. In addition, low-level catabolism of exogenous substrates may support long-term anaerobic survival of some methanotrophic bacteria. PMID:16535004

  13. Studying Denitrification by Aerobic Endospore-forming Bacteria in Soil

    Microsoft Academic Search

    Ines Verbaendert; Paul De Vos

    \\u000a As part of the aerobic endospore-forming bacteria in soil, members of the genus Bacillus sensu stricto and related species are involved in denitrification – one of the main processes in the global nitrogen cycle. So far, only\\u000a limited information on the denitrification abilities and the distribution of the key denitrification genes in these organisms\\u000a is available. This chapter provides a

  14. Biodegradation of Asphalt Cement-20 by Aerobic Bacteria

    PubMed Central

    Pendrys, John P.

    1989-01-01

    Seven gram-negative, aerobic bacteria were isolated from a mixed culture enriched for asphalt-degrading bacteria. The predominant genera of these isolates were Pseudomonas, Acinetobacter, Alcaligenes, Flavimonas, and Flavobacterium. The mixed culture preferentially degraded the saturate and naphthene aromatic fractions of asphalt cement-20. A residue remained on the surface which was resistant to biodegradation and protected the underlying asphalt from biodegradation. The most potent asphalt-degrading bacterium, Acinetobacter calcoaceticus NAV2, excretes an emulsifier which is capable of emulsifying the saturate and naphthene aromatic fractions of asphalt cement-20. This emulsifier is not denatured by phenol. PMID:16347928

  15. Probiotic lactic acid bacteria detoxify N-nitrosodimethylamine.

    PubMed

    Nowak, Adriana; Kuberski, S?awomir; Libudzisz, Zdzis?awa

    2014-01-01

    Humans can be exposed to N-nitroso compounds (NOCs) due to many environmental sources, as well as endogenous formation. The main nitrosamine found in food products and also synthesised in vivo by intestinal microbiota is N-nitrosodimethylamine (NDMA). It can cause cancer of the stomach, kidney and colon. The effect of four probiotic Lactobacillus strains on NDMA was studied under different culture conditions (24 h in MRS, 168 h in modified MRS N, and 168 h in phosphate buffer). HPLC and GC-TEA methods were used for NDMA determination in supernatants. The influence of lactic acid bacteria on NDMA genotoxicity was investigated by means of the comet assay. Additionally, the effect of NDMA (2-100 µg ml(-1)) on the growth and survival of the probiotic strains was studied. The results indicate that the bacteria decreased NDMA concentration by up to 50%, depending on the culture conditions, time of incubation, NDMA concentration, pH and bacterial strain. Lb. brevis 0945 lowered the concentration and genotoxicity of NDMA most effectively by up to 50%. This could be due to either adsorption or metabolism. The growth and survival of the bacteria was not affected by any of the tested NDMA concentrations. PMID:25010287

  16. Determination of peroxy radical-scavenging of lactic acid bacteria.

    PubMed

    Stecchini, M L; Del Torre, M; Munari, M

    2001-02-28

    Responses of lactic acid bacteria (LAB) to peroxy radicals generated via thermal (40 degrees C) decomposition of the diazocompound 2,2,-azo-bis (2-amidinopropane) dihydrochloride (ABAP), were studied. In general, LAB displayed survival curves with shoulders and tails indicative of 'multihit' killing by exposure to peroxy radicals. One strain, Lactococcus lactis subsp. lactis DIP15, producing a slope of 0.0105 in the kinetic analysis when exposed to 4 mM ABAP, exhibited a measurable antioxidant capacity. The other LAB failed to show any significant antioxidant capacity. The antioxidant capacity of strain DIP15 remained constant after cells have been heat-treated, suggesting that compounds bearing free radical scavenging capacity are rather stable. PMID:11252501

  17. Cell wall structure and function in lactic acid bacteria

    PubMed Central

    2014-01-01

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

  18. Aerobic methanotrophic bacteria of cold ecosystems.

    PubMed

    Trotsenko, Yuri A; Khmelenina, Valentina N

    2005-06-01

    This review summarizes the recent advances in understanding the ecophysiological role and structure-function features of methanotrophic bacteria living in various cold ecosystems. The occurrence of methanotrophs in a majority of psychrosphere sites was verified by direct measurement of their methane-utilizing activity, by electron microscopy and immunofluorescent observations, and analyses of specific signatures in cellular phospholipids and total DNAs extracted from environmental samples. Surprisingly, the phenotypic and genotypic markers of virtually all extant methanotrophs were detected in various cold habitats, such as underground waters, Northern taiga and tundra soils, polar lakes and permafrost sediments. Also, recent findings indicated that even after long-term storage in permafrost, some methanotrophs can oxidize and assimilate methane not only at positive but also at subzero temperatures. Pure cultures of psychrophilic and psychrotolerant methanotrophs were isolated and characterized as new genera and species: Methylobacter psychrophilus, Methylosphaera hansonii, Methylocella palustris, Methylocella silvestris, Methylocella tundrae, Methylocapsa acidiphila and Methylomonas scandinavica. However, our knowledge about their adaptive mechanisms and survival in cold ecosystems remains limited and needs to be established using both traditional and molecular microbiological methods. PMID:16329925

  19. Glycerol metabolism and bitterness producing lactic acid bacteria in cidermaking.

    PubMed

    Garai-Ibabe, G; Ibarburu, I; Berregi, I; Claisse, O; Lonvaud-Funel, A; Irastorza, A; Dueñas, M T

    2008-02-10

    Several lactic acid bacteria were isolated from bitter tasting ciders in which glycerol was partially removed. The degradation of glycerol via glycerol dehydratase pathway was found in 22 out of 67 isolates. The confirmation of glycerol degradation by this pathway was twofold: showing their glycerol dehydratase activity and detecting the presence of the corresponding gene by a PCR method. 1,3-propanediol (1,3-PDL) and 3-hydroxypropionic acid (3-HP) were the metabolic end-products of glycerol utilization, and the accumulation of the acrolein precursor 3-hydroxypropionaldehyde (3-HPA) was also detected in most of them. The strain identification by PCR-DGGE rpoB showed that Lactobacillus collinoides was the predominant species and only 2 belonged to Lactobacillus diolivorans. Environmental conditions conducting to 3-HPA accumulation in cidermaking were studied by varying the fructose concentration, pH and incubation temperature in L. collinoides 17. This strain failed to grow with glycerol as sole carbon source and the addition of fructose enhanced both growth and glycerol degradation. Regarding end-products of glycerol metabolism, 1,3-PDL was always the main end-product in all environmental conditions assayed, the only exception being the culture with 5.55 mM fructose, where equimolar amounts of 1,3-PDL and 3-HP were found. The 3-HPA was transitorily accumulated in the culture medium under almost all culture conditions, the degradation rate being notably slower at 15 degrees C. However, no disappearance of 3-HPA was found at pH 3.6, a usual value in cider making. After sugar exhaustion, L. collinoides 17 oxidated lactic acid and/or mannitol to obtain energy and these oxidations were accompanied by the removal of the toxic 3-HPA increasing the 1,3-PDL, 3-HP and acetic acid contents. PMID:18180066

  20. The Benefits of Lactic Acid Bacteria in Yogurt on the Gastrointestinal Function and Health

    Microsoft Academic Search

    Ayman Suliman Mazahreh; Omer Turki Mamdoh Ershidat

    2009-01-01

    2 Abstract: The nutritional value of yogurt and Lactic Acid-producing Bacteria (LAB) on the gastrointestinal health and function, have been investigated in this study. Both Lactobacillus bulgaricus and Streptococcus thermophilus (LAB) species, contribute to the formation of yogurt as a result of anaerobic fermentation of lactic acid in the milk. The present study focuses on the effect of yogurt consumption

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

    PubMed

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

    2015-03-01

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

  2. Antibiotic resistance of lactic acid bacteria isolated from Chinese yogurts.

    PubMed

    Zhou, N; Zhang, J X; Fan, M T; Wang, J; Guo, G; Wei, X Y

    2012-09-01

    The aim of this study was to evaluate the susceptibility of 43 strains of lactic acid bacteria, isolated from Chinese yogurts made in different geographical areas, to 11 antibiotics (ampicillin, penicillin G, roxithromycin, chloramphenicol, tetracycline, chlortetracycline, lincomycin, kanamycin, streptomycin, neomycin, and gentamycin). The 43 isolates (18 Lactobacillus bulgaricus and 25 Streptococcus thermophilus) were identified at species level and were typed by random amplified polymorphic DNA analysis. Thirty-five genotypically different strains were detected and their antimicrobial resistance to 11 antibiotics was determined using the agar dilution method. Widespread resistance to ampicillin, chloramphenicol, chlortetracycline, tetracyclines, lincomycin, streptomycin, neomycin, and gentamycin was found among the 35 strains tested. All of the Strep. thermophilus strains tested were susceptible to penicillin G and roxithromycin, whereas 23.5 and 64.7% of Lb. bulgaricus strains, respectively, were resistant. All of the Strep. thermophilus and Lb. bulgaricus strains were found to be resistant to kanamycin. The presence of the corresponding resistance genes in the resistant isolates was investigated through PCR, with the following genes detected: tet(M) in 1 Lb. bulgaricus and 2 Strep. thermophilus isolates, ant(6) in 2 Lb. bulgaricus and 2 Strep. thermophilus isolates, and aph(3')-IIIa in 5 Lb. bulgaricus and 2 Strep. thermophilus isolates. The main threat associated with these bacteria is that they may transfer resistance genes to pathogenic bacteria, which has been a major cause of concern to human and animal health. To our knowledge, the aph(3')-IIIa and ant(6) genes were found in Lb. bulgaricus and Strep. thermophilus for the first time. Further investigations are required to analyze whether the genes identified in Lb. bulgaricus and Strep. thermophilus isolates might be horizontally transferred to other species. PMID:22916881

  3. Genetically modified lactic acid bacteria: applications to food or health and risk assessment

    Microsoft Academic Search

    Pierre Renault

    2002-01-01

    Lactic acid bacteria have a long history of use in fermented food products. Progress in gene technology allows their modification by introducing new genes or by modifying their metabolic functions. These modifications may lead to improvements in food technology (bacteria better fitted to technological processes, leading to improved organoleptic properties…), or to new applications including bacteria producing therapeutic molecules that

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  5. Phylogenetic Diversity of Aerobic Saprotrophic Bacteria Isolated from the Daqing Oil Field

    Microsoft Academic Search

    T. N. Nazina; A. A. Grigor'yan; Yan-Fen Xue; D. Sh. Sokolova; E. V. Novikova; T. P. Tourova; A. B. Poltaraus; S. S. Belyaev; M. V. Ivanov

    2002-01-01

    A diverse and active microbial community in the stratal waters of the Daqing oil field (China), which is exploited with the use of water-flooding, was found to contain aerobic chemoheterotrophic bacteria (including hydrocarbon-oxidizing ones) and anaerobic fermentative, sulfate-reducing, and methanogenic bacteria. The aerobic bacteria were most abundant in the near-bottom zones of injection wells. Twenty pure cultures of aerobic saprotrophic

  6. Growth Performance and Fecal Microflora of Rats Offered Metabolites from Lactic Acid Bacteria

    Microsoft Academic Search

    T. C. Loh; T. M. Lee; H. L. Foo; F. L. Law; M. A. Ajion

    2008-01-01

    Loh, T.C., Lee, T.M., Foo, H.L., Law, F.L. and Rajion, M.A. 2008. Growth performance and fecal microflora of rats offered metabolites from lactic acid bacteria. J. Appl. Anim. Res., 34: 61–64.The objectives of this experiment were to study the effect of metabolites produced from lactic acid bacteria (LAB) on the growth performance, Enterobacteriaceae and LAB counts in the faeces, faecal

  7. Lactic acid bacteria and yeasts isolated from the starter doughs for Chinese steamed buns in Thailand

    Microsoft Academic Search

    Naphatrapi Luangsakul; Suwimon Keeratipibul; Sasitorn Jindamorakot; Somboon Tanasupawat

    2009-01-01

    Isolation of lactic acid bacteria (LAB) and yeasts from the starter dough of Chinese steamed buns from four different commercial sources in Thailand was carried out. Thirty-one lactic acid bacteria and eight yeast strains were isolated. Total counts of LAB were from 1.8×104 to 108colonies\\/g sample, whilst yeasts were very low from 10 to 2.3×102colonies\\/g sample. The pH values of

  8. [Biological deacidification of wines using lactic-acid bacteria and yeasts].

    PubMed

    Eliseeva, G S; Nagornaia, S S; Zherebilo, O E; Podgorski?, V S; Ignatova, E A

    2001-01-01

    Based on a study of 200 lactic-acid bacteria monocultures and 30 associating lactic bacteria and yeasts cultures, a stable association was created formed by Leuconostoc oenos, Pediococcus pentosaceus and Saccharomyces cerevisiae yeasts, intended for the biological deacidification of wine. Physiology of microorganisms and their effect on the wine chemical composition was studied. By means of selective association, high quality fine wines were produced from the high-acid wines. PMID:11530675

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

    SciTech Connect

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

    1986-05-01

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

  10. Removal of 3-methylindole by lactic acid bacteria in vitro

    PubMed Central

    MENG, XIAO; HE, ZHI-FEI; LI, HONG-JUN; ZHAO, XIN

    2013-01-01

    3-Methylindole (3MI) is a substance with an unpleasant odor that is found in intact male pigs and is known to negatively affect consumers of pork. The growth of four strains of lactic acid bacteria [Lactobacillus brevis 1.12 (L. brevis 1.12), L. plantarum 102, L. casei 6103 and L. plantarum ATCC8014] in incubation medium with 3MI was studied. The four strains were tested for their ability to remove 3MI from the medium. The growth of L. brevis 1.12 remained steady as the levels of 3MI increased 3MI from 0.2 to 1.0 ?g/ml. The 3MI removal ability of L. brevis 1.12 was the strongest among the four strains, and the highest removal rate was 65.35±0.3% in 1 ml incubation medium containing 1.0 ?g/ml 3MI for 120 h. Furthermore, the supernatant fluid of the fermentation broth of L. brevis 1.12 had a stronger ability to remove 3MI than cell pellets and cell extracts and the removal rate was 14.4±0.3% in 24 h. Further results indicate that the mode of removal of 3MI was not through the physical binding of cells by L. brevis 1.12. PMID:24137302

  11. Fermentation of Aqueous Plant Seed Extracts by Lactic Acid Bacteria

    PubMed Central

    Schaffner, Donald W.; Beuchat, Larry R.

    1986-01-01

    The effects of lactic acid bacterial fermentation on chemical and physical changes in aqueous extracts of cowpea (Vigna unguiculata), peanut (Arachis hypogea), soybean (Glycine max), and sorghum (Sorghum vulgare) were studied. The bacteria investigated were Lactobacillus helveticus, L. delbrueckii, L. casei, L. bulgaricus, L. acidophilus, and Streptococcus thermophilus. Organisms were inoculated individually into all of the seed extracts; L. bulgaricus and S. thermophilus were also evaluated together as inocula for fermenting the legume extracts. During fermentation, bacterial population and changes in titratable acidity, pH, viscosity, and color were measured over a 72-h period at 37°C. Maximum bacterial populations, titratable acidity, pH, and viscosity varied depending upon the type of extract and bacterial strain. The maximum population of each organism was influenced by fermentable carbohydrates, which, in turn, influenced acid production and change in pH. Change in viscosity was correlated with the amount of protein and titratable acidity of products. Color was affected by pasteurization treatment and fermentation as well as the source of extract. In the extracts inoculated simultaneously with L. bulgaricus and S. thermophilus, a synergistic effect resulted in increased bacterial populations, titratable acidity, and viscosity, and decreased pH in all the legume extracts when compared to the extracts fermented with either of these organisms individually. Fermented extracts offer potential as substitutes for cultured dairy products. PMID:16347053

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

    PubMed Central

    Vasama, Mari; Kumar, Himanshu; Salminen, Seppo; Haskard, Carolyn A.

    2014-01-01

    Paralytic shellfish toxins (PSTs) are non-protein neurotoxins produced by saltwater dinoflagellates and freshwater cyanobacteria. The ability of Lactobacillus rhamnosus strains GG and LC-705 (in viable and non-viable forms) to remove PSTs (saxitoxin (STX), neosaxitoxin (neoSTX), gonyautoxins 2 and 3 (GTX2/3), C-toxins 1 and 2 (C1/2)) from neutral and acidic solution (pH 7.3 and 2) was examined using HPLC. Binding decreased in the order of STX ~ neoSTX > C2 > GTX3 > GTX2 > C1. Removal of STX and neoSTX (77%–97.2%) was significantly greater than removal of GTX3 and C2 (33.3%–49.7%). There were no significant differences in toxin removal capacity between viable and non-viable forms of lactobacilli, which suggested that binding rather than metabolism is the mechanism of the removal of toxins. In general, binding was not affected by the presence of other organic molecules in solution. Importantly, this is the first study to demonstrate the ability of specific probiotic lactic bacteria to remove PSTs, particularly the most toxic PST-STX, from solution. Further, these results warrant thorough screening and assessment of safe and beneficial microbes for their usefulness in the seafood and water industries and their effectiveness in vivo. PMID:25046082

  13. Characterisation of lactic acid bacteria isolated from fermented milk "laban".

    PubMed

    Chammas, Gisele I; Saliba, Rachad; Corrieu, Georges; Béal, Catherine

    2006-07-01

    The technological properties of 96 lactic acid bacteria isolated from Lebanese traditional fermented milk "laban" were characterised. They were classified by phenotypic and biochemical analyses as Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus, thus indicating that laban is a fermented milk similar to yogurt. Most strains of L. bulgaricus (87.5%) exhibited a high acidification activity, whereas strains of streptococci showed low acidification ability. 33.3% of streptococci strains and 25% of lactobacilli strains displayed similar acidification performances as European strains. Results obtained for syneresis, texture and rheological parameters led us to consider that isolated strains were not low polymer-producing strains. Some of them displayed interesting characteristics such as low syneresis and high values for rheological parameters. The major flavour compounds found in pure cultures were acetaldehyde, acetone, 2-butanone, dimethyl disulfide, acetoin, 2,3-butanedione, 2,3-pentanedione, and acetic, hexanoic and butanoic acids. Acetaldehyde (7.4%) and organic acids (48.3%) were mainly produced by L. bulgaricus strains, whereas streptococci cultures contained high relative levels of 2,3-butanedione and acetoin, which represented around 82% of the total flavour compounds. Finally, strains isolated from laban samples exhibited different technological properties than those used in yogurt production, thus conferring specific characteristics to this product. PMID:16701913

  14. Amino acid catabolic pathways of lactic acid bacteria.

    PubMed

    Fernández, María; Zúñiga, Manuel

    2006-01-01

    Lactic acid bacteria (LAB) constitute a diverse group of Gram positive obligately fermentative microorganisms which include both beneficial and pathogenic strains. LAB generally have complex nutritional requirements and therefore they are usually associated with nutrient-rich environments such as animal bodies, plants and foodstuffs. Amino acids represent an important resource for LAB and their utilization serves a number of physiological roles such as intracellular pH control, generation of metabolic energy or redox power, and resistance to stress. As a consequence, the regulation of amino acid catabolism involves a wide set of both general and specific regulators and shows significant differences among LAB. Moreover, due to their fermentative metabolism, LAB amino acid catabolic pathways in some cases differ significantly from those described in best studied prokaryotic model organisms such as Escherichia coli or Bacillus subtilis. Thus, LAB amino acid catabolism constitutes an interesting case for the study of metabolic pathways. Furthermore, LAB are involved in the production of a great variety of fermented products so that the products of amino acid catabolism are also relevant for the safety and the quality of fermented products. PMID:16893752

  15. Removal of paralytic shellfish toxins by probiotic lactic acid bacteria.

    PubMed

    Vasama, Mari; Kumar, Himanshu; Salminen, Seppo; Haskard, Carolyn A

    2014-01-01

    Paralytic shellfish toxins (PSTs) are non-protein neurotoxins produced by saltwater dinoflagellates and freshwater cyanobacteria. The ability of Lactobacillus rhamnosus strains GG and LC-705 (in viable and non-viable forms) to remove PSTs (saxitoxin (STX), neosaxitoxin (neoSTX), gonyautoxins 2 and 3 (GTX2/3), C-toxins 1 and 2 (C1/2)) from neutral and acidic solution (pH 7.3 and 2) was examined using HPLC. Binding decreased in the order of STX ~ neoSTX > C2 > GTX3 > GTX2 > C1. Removal of STX and neoSTX (77%-97.2%) was significantly greater than removal of GTX3 and C2 (33.3%-49.7%). There were no significant differences in toxin removal capacity between viable and non-viable forms of lactobacilli, which suggested that binding rather than metabolism is the mechanism of the removal of toxins. In general, binding was not affected by the presence of other organic molecules in solution. Importantly, this is the first study to demonstrate the ability of specific probiotic lactic bacteria to remove PSTs, particularly the most toxic PST-STX, from solution. Further, these results warrant thorough screening and assessment of safe and beneficial microbes for their usefulness in the seafood and water industries and their effectiveness in vivo. PMID:25046082

  16. Lactic acid bacteria: promising supplements for enhancing the biological activities of kombucha.

    PubMed

    Nguyen, Nguyen Khoi; Dong, Ngan Thi Ngoc; Nguyen, Huong Thuy; Le, Phu Hong

    2015-01-01

    Kombucha is sweetened black tea that is fermented by a symbiosis of bacteria and yeast embedded within a cellulose membrane. It is considered a health drink in many countries because it is a rich source of vitamins and may have other health benefits. It has previously been reported that adding lactic acid bacteria (Lactobacillus) strains to kombucha can enhance its biological functions, but in that study only lactic acid bacteria isolated from kefir grains were tested. There are many other natural sources of lactic acid bacteria. In this study, we examined the effects of lactic acid bacteria from various fermented Vietnamese food sources (pickled cabbage, kefir and kombucha) on kombucha's three main biological functions: glucuronic acid production, antibacterial activity and antioxidant ability. Glucuronic acid production was determined by high-performance liquid chromatography-mass spectrometry, antibacterial activity was assessed by the agar-well diffusion method and antioxidant ability was evaluated by determining the 2,2-diphenyl-1-picrylhydrazyl radical scavenging capacity. Four strains of food-borne pathogenic bacteria were used in our antibacterial experiments: Listeria monocytogenes ATCC 19111, Escherichia coli ATCC 8739, Salmonella typhimurium ATCC 14028 and Bacillus cereus ATCC 11778. Our findings showed that lactic acid bacteria strains isolated from kefir are superior to those from other sources for improving glucuronic acid production and enhancing the antibacterial and antioxidant activities of kombucha. This study illustrates the potential of Lactobacillus casei and Lactobacillus plantarum isolated from kefir as biosupplements for enhancing the bioactivities of kombucha. PMID:25763303

  17. Aerobic salivary bacteria in wild and captive Komodo dragons.

    PubMed

    Montgomery, Joel M; Gillespie, Don; Sastrawan, Putra; Fredeking, Terry M; Stewart, George L

    2002-07-01

    During the months of November 1996, August 1997, and March 1998, saliva and plasma samples were collected for isolation of aerobic bacteria from 26 wild and 13 captive Komodo dragons (Varanus komodoensis). Twenty-eight Gram-negative and 29 Gram-positive species of bacteria were isolated from the saliva of the 39 Komodo dragons. A greater number of wild than captive dragons were positive for both Gram-negative and Gram-positive bacteria. The average number of bacterial species within the saliva of wild dragons was 46% greater than for captive dragons. While Escherichia coli was the most common bacterium isolated from the saliva of wild dragons, this species was not present in captive dragons. The most common bacteria isolated from the saliva of captive dragons were Staphylococcus capitis and Staphylococcus capitis and Staphylococcus caseolyticus, neither of which were found in wild dragons. High mortality was seen among mice injected with saliva from wild dragons and the only bacterium isolated from the blood of dying mice was Pasteurella multocida. A competitive inhibition enzyme-linked immunosorbent assay revealed the presence of anti-Pasteurella antibody in the plasma of Komodo dragons. Four species of bacteria isolated from dragon saliva showed resistance to one or more of 16 antimicrobics tested. The wide variety of bacteria demonstrated in the saliva of the Komodo dragon in this study, at least one species of which was highly lethal in mice and 54 species of which are known pathogens, support the observation that wounds inflicted by this animal are often associated with sepsis and subsequent bacteremia in prey animals. PMID:12238371

  18. Lactic acid bacteria effective for regulating the growth of contaminant bacteria during the fermentation of Undaria pinnatifida (Phaeophyta)

    Microsoft Academic Search

    Motoharu Uchida; Masakazu Murata; Fumiyasu Ishikawa

    2007-01-01

    Lactic acid fermentation of seaweed is a recent topic and quite limited information is available on culture conditions. To\\u000a know the suitable strains for use as a starter culture for seaweed fermentation, 14 lactic acid bacteria (LAB) strains, including\\u000a 11 species, were tested in culture conditions prepared with or without salt. A commercial product of Undaria pinnatifida powder was used

  19. Systems biology of lactic acid bacteria: a critical review

    PubMed Central

    2011-01-01

    Understanding the properties of a system as emerging from the interaction of well described parts is the most important goal of Systems Biology. Although in the practice of Lactic Acid Bacteria (LAB) physiology we most often think of the parts as the proteins and metabolites, a wider interpretation of what a part is can be useful. For example, different strains or species can be the parts of a community, or we could study only the chemical reactions as the parts of metabolism (and forgetting about the enzymes that catalyze them), as is done in flux balance analysis. As long as we have some understanding of the properties of these parts, we can investigate whether their interaction leads to novel or unanticipated behaviour of the system that they constitute. There has been a tendency in the Systems Biology community to think that the collection and integration of data should continue ad infinitum, or that we will otherwise not be able to understand the systems that we study in their details. However, it may sometimes be useful to take a step back and consider whether the knowledge that we already have may not explain the system behaviour that we find so intriguing. Reasoning about systems can be difficult, and may require the application of mathematical techniques. The reward is sometimes the realization of unexpected conclusions, or in the worst case, that we still do not know enough details of the parts, or of the interactions between them. We will discuss a number of cases, with a focus on LAB-related work, where a typical systems approach has brought new knowledge or perspective, often counterintuitive, and clashing with conclusions from simpler approaches. Also novel types of testable hypotheses may be generated by the systems approach, which we will illustrate. Finally we will give an outlook on the fields of research where the systems approach may point the way for the near future. PMID:21995498

  20. Nonstarter lactic acid bacteria volatilomes produced using cheese components.

    PubMed

    Sgarbi, E; Lazzi, C; Tabanelli, G; Gatti, M; Neviani, E; Gardini, F

    2013-07-01

    In long-ripened cheese, flavor formation occurs during ripening. The metabolism of lactic acid bacteria (LAB) leads to the production of different compounds that contribute to the flavor of cheese. The contribution of LAB to the formation of cheese flavor has previously been studied. However, the specific nonstarter LAB (NSLAB) metabolic reactions in ripened cheese that lead to the formation of flavor compounds remain unclear. In ripened cheese, the nutrient sources available include small peptides or amino acids, citrate, lactate, free fatty acids, and starter LAB cell lysis products. Thus, the aim of this study was to evaluate the ability of NSLAB to produce volatile flavor compounds by using an in vitro system that used only the nutrients available in ripened cheese as the energy source. Moreover, the potential contribution of the NSLAB volatilome on total cheese flavor is discussed. For this purpose, the production of volatile compounds on cheese-based medium (CBM) and on starter LAB lysed cell medium (LCM) by 2 Lactobacillus casei and 2 Lactobacillus rhamnosus strains, previously isolated from ripened Parmigiano Reggiano cheese, was investigated. The generated volatile compounds were analyzed with head-space gas chromatography mass spectrometry. Overall, ketones, aldehydes, alcohols, and acids were the most abundant compounds produced. Differences in volatilome production were found between NSLAB grown in LCM and CBM. The catabolic metabolism of amino acids and fatty acids were required for NSLAB growth on LCM. Conversely, pyruvate metabolism was the main catabolic pathway that supported growth of NSLAB in CBM. This study can be considered a first step toward a better understanding of how microbiota involved in the long ripening of cheese may contribute to the development of cheese flavor. PMID:23684038

  1. Animal Rennets as Sources of Dairy Lactic Acid Bacteria

    PubMed Central

    Cruciata, Margherita; Sannino, Ciro; Ercolini, Danilo; Scatassa, Maria L.; De Filippis, Francesca; Mancuso, Isabella; La Storia, Antonietta; Moschetti, Giancarlo

    2014-01-01

    The microbial composition of artisan and industrial animal rennet pastes was studied by using both culture-dependent and -independent approaches. Pyrosequencing targeting the 16S rRNA gene allowed to identify 361 operational taxonomic units (OTUs) to the genus/species level. Among lactic acid bacteria (LAB), Streptococcus thermophilus and some lactobacilli, mainly Lactobacillus crispatus and Lactobacillus reuteri, were the most abundant species, with differences among the samples. Twelve groups of microorganisms were targeted by viable plate counts revealing a dominance of mesophilic cocci. All rennets were able to acidify ultrahigh-temperature-processed (UHT) milk as shown by pH and total titratable acidity (TTA). Presumptive LAB isolated at the highest dilutions of acidified milks were phenotypically characterized, grouped, differentiated at the strain level by randomly amplified polymorphic DNA (RAPD)-PCR analysis, and subjected to 16S rRNA gene sequencing. Only 18 strains were clearly identified at the species level, as Enterococcus casseliflavus, Enterococcus faecium, Enterococcus faecalis, Enterococcus lactis, Lactobacillus delbrueckii, and Streptococcus thermophilus, while the other strains, all belonging to the genus Enterococcus, could not be allotted into any previously described species. The phylogenetic analysis showed that these strains might represent different unknown species. All strains were evaluated for their dairy technological performances. All isolates produced diacetyl, and 10 of them produced a rapid pH drop in milk, but only 3 isolates were also autolytic. This work showed that animal rennet pastes can be sources of LAB, mainly enterococci, that might contribute to the microbial diversity associated with dairy productions. PMID:24441167

  2. Short communication Metatranscriptome analysis of lactic acid bacteria during kimchi fermentation with

    E-print Network

    Bae, Jin-Woo

    Short communication Metatranscriptome analysis of lactic acid bacteria during kimchi fermentation microbial diversity and biological activity during the fermentation of kimchi, a traditional Korean. Metagenomic analysis revealed 23 LAB related to kimchi fermentation [defined as bacteria with more than a 1

  3. Production of Ethylesters by Some Lactic Acid and Psychrotrophic Bacteria1

    Microsoft Academic Search

    A. Hosono; J. A. Elliott; W. A. McGugan

    1974-01-01

    The production of esterases by five strains of lactic acid bacteria (Strepto- coccus diacetilactis ATCC 15346, S. \\/ac- t\\/s ML3, S. cremoris TR, Lactobacillus No. 81, and L. casei I_,323) and two strains of psyehrotrophie bacteria be- longing to the genus Pseudomonas (Strains No. 50 and No. 53) were studied. All strains contained esterase capable of esterfiqcation of butyric and

  4. Identification and succession of lactic acid bacteria during fermentation of 'urutan', a Balinese indigenous fermented sausage

    Microsoft Academic Search

    N. S. Antara; I. N. Sujaya; A. Yokota; K. Asano; W. R. Aryanta; F. Tomita

    2002-01-01

    'Urutan' is a Balinese traditional fermented sausage, which is made of lean pork and fat mixed with spices, sugar, and salt. The mixture is stuffed into cleaned pig intestine and fermented under uncontrolled condition during sun drying for 5 days. The investigation showed that lactic acid bacteria (LAB) were the dominating bacteria during 'urutan' fermentation. Among the 71 isolates obtained,

  5. Synthesis of the cancer preventive peptide lunasin by lactic acid bacteria during sourdough fermentation.

    PubMed

    Rizzello, Carlo G; Nionelli, Luana; Coda, Rossana; Gobbetti, Marco

    2012-01-01

    This study aimed to exploit the potential of sourdough lactic acid bacteria to release lunasin during fermentation of cereal and nonconventional flours. The peptidase activities of a large number of sourdough lactic acid bacteria were screened using synthetic substrates. Selected lactic acid bacteria were used as sourdough starters to ferment wholemeal wheat, soybean, barley, amaranth, and rye flours. Proteinase activity during fermentation was characterized by SDS-PAGE analysis of the water-soluble extracts. Albumins having molecular masses of 18 to 22 kDa, which included the size of lunasin precursors, were markedly affected by proteolysis of lactic acid bacteria. After fermentation, lunasin from the water-soluble extracts was quantified, purified, and identified through RP-HPLC and nano-LC-ESI-MS analyses. Compared to control doughs, the concentration of lunasin increased up to 2-4 times during fermentation. Lactobacillus curvatus SAL33 and Lactobacillus brevis AM7 synthesized the highest concentrations of lunasin in all the flours. Besides the presence of the entire lunasin sequence, fragments containing the immunoreactive epitope RGDDDDDDDDD were also found. This study shows that fermentation by lactic acid bacteria increased the concentration of lunasin to levels that would suggest new possibilities for the biological synthesis and for the formulation of functional foods. PMID:22098174

  6. Oat bran ?-gluco- and xylo-oligosaccharides as fermentative substrates for lactic acid bacteria

    Microsoft Academic Search

    Pia Kontula; Atte von Wright; Tiina Mattila-Sandholm

    1998-01-01

    The influence of oat bran oligosaccharides on carbohydrate utilization and fermentation end-products was studied with reference to three different lactic acid bacteria (LAB: Lactobacillus rhamnosus, Lactobacillus plantarum and Lactococcus lactis). The main results were that all three LAB utilized oat ?-gluco-oligosaccharides, while only L. plantarum utilized xylo-oligosaccharides. The main products of LAB metabolism were lactic acid, acetic acid, formic acid

  7. Effect of inoculating lactic acid bacteria starter cultures on the nitrite concentration of fermenting Chinese paocai

    Microsoft Academic Search

    Ping-Mei Yan; Wen-Tong Xue; Sze-Sze Tan; Hui Zhang; Xiao-Hui Chang

    2008-01-01

    Lactic acid bacteria (LAB) isolated from Chinese paocai (a type of mildly salted and lactic acid fermented vegetable) were studied for their ability to deplete nitrite during fermentation. Lactobacillus pentosus, Lb. plantarum, Leuconostoc mesenteroides, Lb. brevis, Lb. lactis, Lb. fermentum depleted 99.6%, 99.3%, 99.2%, 97.0%, 98.5% and 98.8% of the initial nitrite present in de Man, Rogosa and Sharpe (MRS)

  8. Use of virginiamycin to control the growth of lactic acid bacteria during alcohol fermentation

    Microsoft Academic Search

    S H Hynes; D M Kjarsgaard; K C Thomas; W M Ingledew

    1997-01-01

      The antibiotic virginiamycin was investigated for its effects on growth and lactic acid production by seven strains of lactobacilli\\u000a during the alcoholic fermentation of wheat mash by yeast. The lowest concentration of virginiamycin tested (0.5?mg Lactrol\\u000a TMkg?1 mash), was effective against most of the lactic acid bacteria under study, but Lactobacillus plantarum was not significantly inhibited at this concentration. The

  9. [Comparison of methods for the detection and enumeration of lactic acid bacteria in yogurt].

    PubMed

    Briceño, A G; Martínez, R

    1995-09-01

    It is generally agreed that the population of lactic acid bacteria in yogurt must be not less than 10(6) ufc/g. Viability of the lactic flora until the end of shelf-life is affected for many factors, which has incidence in the recuperability of this microflora. MRS and LEE agar were selected for the total count of lactic bacteria, the M17 was used for the S salivarius ssp thermophilus and the RCA for L. delbrueckii ssp bulgaricus. Different methodologies were used for detection and enumeration of this bacteria: direct plate count; thermal treatment and recuperation of the injured cells in Soy Tripticase broth. The enumeration was done at time zero and 3 hours after the start of the fermentative process and during storage at 4, 12 and 21 days. The results shown an excellent recuperability of the lactic flora in the selected media and methods that were used: however the enumeration was significatively lower in the RCA agar. The counts in the LEE agar shown a better recuperability. The thermal treatment affected negatively the counts of lactic flora and the repair method shown better results in the yogurt sample during storage. pH and acidity were determined at the beginning and during the storage period. It was observed a pH decrease because of the lactic acid production at the end of shelf-life. PMID:9382680

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

    PubMed Central

    2012-01-01

    Background The objectives of the present study were to investigate the efficacy of the mixed culture of Lactobacillus acidophilus (DSM 20242), Bifidobacterium bifidum (DSM 20082) and Lactobacillus helveticus (CK60) in the fermentation of maize and the evaluation of the effect of the fermented meal on the lipid profile of rats. Methods Rats were randomly assigned to 3 groups and each group placed on a Diet A (high fat diet into which a maize meal fermented with a mixed culture of Lb acidophilus (DSM 20242), B bifidum (DSM 20082) and Lb helveticus (CK 60) was incorporated), B (unfermented high fat diet) or C (commercial rat chow) respectively after the first group of 7 rats randomly selected were sacrificed to obtain the baseline data. Thereafter 7 rats each from the experimental and control groups were sacrificed weekly for 4 weeks and the plasma, erythrocytes, lipoproteins and organs of the rats were assessed for cholesterol, triglyceride and phospholipids. Results Our results revealed that the mixed culture of Lb acidophilus (DSM 20242), B bifidum (DSM 20082) and Lb helveticus (CK 60) were able to grow and ferment maize meal into ‘ogi’ of acceptable flavour. In addition to plasma and hepatic hypercholesterolemia and hypertriglyceridemia, phospholipidosis in plasma, as well as cholesterogenesis, triglyceride constipation and phospholipidosis in extra-hepatic tissues characterized the consumption of unfermented hyperlipidemic diets. However, feeding the animals with the fermented maize diet reversed the dyslipidemia. Conclusion The findings of this study indicate that consumption of mixed culture lactic acid bacteria (Lb acidophilus (DSM 20242), Bifidobacterium bifidum (DSM 20082) and Lb helveticus (CK 60) fermented food results in the inhibition of fat absorption. It also inhibits the activity of HMG CoA reductase. This inhibition may be by feedback inhibition or repression of the transcription of the gene encoding the enzyme via activation of the sterol regulatory element binding protein (SREBP) transcription factor. It is also possible that consumption of fermented food enhances conversion of cholesterol to bile acids by activating cholesterol-7?-hydroxylase. PMID:23231860

  11. Cancer Preventive Potential of Kimchi Lactic Acid Bacteria (Weissella cibaria, Lactobacillus plantarum)

    PubMed Central

    Kwak, Shin-Hye; Cho, Young-Mi; Noh, Geon-Min; Om, Ae-Son

    2014-01-01

    The number of death due to cancer has been increasing in Korea. Chemotherapy is known to cause side effects because it damages not only cancerous cells but healthy cells. Recently, attention has focused on food-derived chemopreventive and anti-tumor agents or formulations with fewer side effects. Kimchi, most popular and widely consumed in Korea, contains high levels of lactic acid bacteria and has been shown to possess chemopreventive effects. This review focuses on Weissella cibaria and Lactobacillus plantarum, the representatives of kimchi lactic acid bacteria, in terms of their abilities to prevent cancer. Further studies are needed to understand the mechanisms by which lactic acid bacteria in kimchi prevent carcinogenic processes and improve immune functions. PMID:25574459

  12. Inoculation of beef with lactic-acid bacteria prior to vacuum packaging

    E-print Network

    Hall, Lester Cedric

    1978-01-01

    INOCULATION OF BEEF WITH LACTIC-ACID BACTERIA PRIOR TO VACUUM PACKAGING A Thesis by LESTER CEDRIC HALL Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE... August 1978 Major Subject: Animal Science INOCULATION OF BEEF WITH LACTIC-ACID BACTERIA PRIOR TO VACUUM PACKAGING A Thesis by LESTER CEDRIC HALL Approved as to style and content by: 1 ( (Co- hairman of C mmittee) (Co-Chakrm 'g of Committee) (He...

  13. Precipitation of Dolomite in Aerobic Culture Experiments Using Halophilic Bacteria

    NASA Astrophysics Data System (ADS)

    Roman, M. S.; Vasconcelos, C.; McKenzie, J. A.

    2003-12-01

    The study of carbonate biomineralization in hypersaline environments provides information about the key role microorganisms have played in global carbon cycling, especially in the Precambrian. Recently, a microbial dolomite model was proposed based on the study of a hypersaline coastal lagoon, Lagoa Vermelha, Rio de Janeiro (Brazil). This model suggests that sulfate-reducing bacteria mediate dolomite precipitation by increasing pH and removing the sulfate inhibitor. The anoxic conditions of this system may not, however, apply to all ancient dolomite formation. Dolomite is an abundant carbonate mineral found widespread in the geological record in a variety of environmental settings. Thus, a single microbial dolomite model probably cannot explain its widespread distribution and a broad spectrum of conditions may be linked with its formation. In contrast to Lagoa Vermelha, Brejo do Espinho, a shallow hypersaline lagoon located in the same region, is a dolomite-forming environment with oxic bottom conditions. The sediment comprises primarily high Mg-calcite and Ca-dolomite. Heterotrophic microorganisms have been isolated from algal mats growing in Brejo do Espinho, and biomineralization experiments have been conducted at variable temperatures (15, 20, 25, 30, 35 and 40° C) and salinities (sea water and 2x seawater) to simulate the natural environmental conditions. After a 20-day incubation period, several aerobic culture experiments have crystal growth of Ca-dolomite and high Mg-calcite. Our study demonstrates that, under aerobic conditions, heterotrophic microorganisms can mediate dolomite precipitation. These results indicate that microbial dolomite precipitation is not necessarily linked to any particular group of organisms or specific metabolic processes or even a specific environment, i.e., it is not exclusively an anoxic mineral but can be precipitated in the presence of oxygen. This has implications for the distribution of dolomite in the geologic record.

  14. The antimicrobial activity of lactic acid bacteria from fermented maize (kenkey) and their interactions during fermentation.

    PubMed

    Olsen, A; Halm, M; Jakobsen, M

    1995-11-01

    A total of 241 lactic acid bacteria belonging to Lactobacillus plantarum, Pediococcus pentosaceus, Lactobacillus fermentum/reuteri and Lactobacillus brevis from various processing stages of maize dough fermentation were investigated. Results indicated that each processing stage has its own microenvironment with strong antimicrobial activity. About half of the Lact. plantarum and practically all of the Lact. fermentum/reuteri investigated were shown to inhibit other Gram-positive and Gram-negative bacteria, explaining the elimination of these organisms during the initial processing stages. Further, widespread microbial interactions amounting to 85% to 18% of all combinations tested were demonstrated amongst lactic acid bacteria within the various processing stages, i.e. raw material, steeping, 0 h and 48 h of fermentation, explaining the microbial succession taking place amongst lactic acid bacteria during fermentation. The antimicrobial effect was explained by the combined effect of acids, compounds sensitive to proteolytic enzymes and other compounds with antimicrobial activity with the acid production being the most important factor. The pattern of antimicrobial factors was not species-specific and the safety and storage stability of fermented maize seem to depend on a mixed population of lactic acid bacteria with different types of antimicrobial characteristics. This means that introduction of pure cultures as starters may impose a risk to the product. PMID:8567490

  15. Cell wall component and mycotoxin moieties involved in the binding of fumonisin B1 and B2 by lactic acid bacteria

    E-print Network

    Paris-Sud XI, Université de

    @clermont.inra.fr KEYWORDS binding ; bioavailability ; detoxification ; fumonisins ; lactic acid bacteria ; peptidoglycan ; probiotics ABSTRACT Aims: The ability of lactic acid bacteria (LAB) to bind fumonisins B1 and B2 (FB1, FB2, respectively, involved in the binding interaction. Significance and Impact of the Study: Lactic acid bacteria

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

    PubMed Central

    2011-01-01

    Every biotechnology process that relies on the use of bacteria to make a product or to overproduce a molecule may, at some time, struggle with the presence of virulent phages. For example, phages are the primary cause of fermentation failure in the milk transformation industry. This review focuses on the recent scientific advances in the field of lactic acid bacteria phage research. Three specific topics, namely, the sources of contamination, the detection methods and the control procedures will be discussed. PMID:21995802

  17. Isolation, characterisation and identification of lactic acid bacteria from bushera: a Ugandan traditional fermented beverage

    Microsoft Academic Search

    C. M. B. K. Muyanja; J. A. Narvhus; J. Treimo; T. Langsrud

    2003-01-01

    One hundred and thirteen strains of lactic acid bacteria (LAB) were selected from 351 isolates from 15 samples of traditionally fermented household bushera from Uganda and also from laboratory-prepared bushera. Isolates were phenotypically characterised by their ability to ferment 49 carbohydrates using API 50 CHL kits and additional biochemical tests. Coliforms, yeasts and LAB were enumerated in bushera. The pH,

  18. Disease-Dependent Adhesion of Lactic Acid Bacteria to the Human Intestinal Mucosa

    Microsoft Academic Search

    Arthur C. Ouwehand; Seppo Salminen; Peter J. Roberts; Jari Ovaska; Eeva Salminen

    2003-01-01

    Their adhesion to the intestinal mucosa is considered one of the main reasons for the beneficial health effects of specific lactic acid bacteria (LAB). However, the influence of disease on the mucosal adhesion is largely unknown. Adhesion of selected LAB to resected colonic tissue and mucus was determined in patients with three major intestinal diseases (i.e., diverticulitis, rectal carcinoma, and

  19. Interaction between dairy yeasts and lactic acid bacteria strains during milk fermentation

    Microsoft Academic Search

    Pablo Álvarez-Martín; Ana Belén Flórez; Ana Hernández-Barranco; Baltasar Mayo

    2008-01-01

    Twelve yeast strains of eight different species and four lactic acid bacteria (LAB) strains belonging to three species were inoculated into UHT skimmed milk separately and as co-cultures to determine their growth, activities and interactions. pH was recorded at the end of fermentation, and both yeasts and LAB enumerated by selective culturing. Organic acids and volatile compounds were analysed by

  20. Production of high ?-aminobutyric acid (GABA) sour kimchi using lactic acid bacteria isolated from mukeunjee kimchi

    Microsoft Academic Search

    Seung Yong Cho; Min Jung Park; Ki Myong Kim; Jee-Hoon Ryu; Hyun Jin Park

    2011-01-01

    A sour kimchi product with an elevated amount of ?-aminobutyric acid (GABA) was produced using starter lactic acid bacteria\\u000a (LAB) for mukeunjee kimchi fermentation. The starter LAB were screened and isolated from the commercial mukeunjee kimchi product that showed the highest GABA content and was identified as Lactobacillus buchneri. The maximum GABA production of L. buchneri in MRS media was

  1. Growth of lactic acid bacteria and Rhizopus oligosporus during barley tempeh fermentation

    Microsoft Academic Search

    Xin Mei Feng; Anders R. B. Eriksson; Johan Schnürer

    2005-01-01

    The zygomycete Rhizopus oligosporus is traditionally used to ferment soybean tempeh, but it is also possible to ferment other legumes and cereals to tempeh. The traditional soybean tempeh harbours a multitude of microorganisms with potentially beneficial or detrimental effects on quality. Lactic acid bacteria (LAB) have positive effects on the safety of soybean tempeh, but the effects of LAB on

  2. Fed-batch Fermentation of Lactic Acid Bacteria to Improve Biomass Production: A Theoretical Approach

    Microsoft Academic Search

    Boon Beng Lee; Heng Jin Tham; Eng Seng Chan

    2007-01-01

    Recently, fed-batch fermentation has been introduced in an increasing number of fermentation processes. Previous researches showed that fed-batch fermentation can increase the biomass yield of many strains. Improvement of the biomass yield is interested because biomass from lactic acid bacteria (LAB) fermentation is widely used in food and pharmaceutical industry. The aim of this research is to study the ability

  3. The role of interaction between yeasts and lactic acid bacteria in African fermented milks: a review

    Microsoft Academic Search

    Judith A. Narvhus; Tendekayi Henry Gadaga

    2003-01-01

    Yeasts are present in indigenous African fermented milks in numbers up to log 8 cfu g?1, together with a varied lactic acid bacteria (LAB) flora, and therefore potentially contribute to product characteristics. However, interaction between yeasts and LAB in these products has received little notice.In studies of indigenous fermented milk in Zimbabwe and Uganda, many samples contained more than one

  4. Effect of Lactic Acid Fermentation Bacteria on Plant Growth and Soil Humus Formation

    Microsoft Academic Search

    T. Higa; S. Kinjo

    A study was conducted to determine if lactic acid bacteria, when inoculated into soil amended with organic materials, could enhance decomposition and the release of plant nutrients, and increase soil humus formation. The addition of EM 4 to soil amended with fresh green grass increased the growth of cucumber over that of the unamended and fertilized controls, while woodchips appeared

  5. Glucansucrases from lactic acid bacteria which produce water-insoluble polysaccharides from sucrose

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dextrans and related glucans produced from sucrose by lactic acid bacteria have been studied for many years and are used in numerous commercial applications and products. Most of these glucans are water-soluble, except for a few notable exceptions from cariogenic Streptococcus spp. and a very small ...

  6. Can Immunoregulatory Lactic Acid Bacteria Be Used as Dietary Supplements to Limit Allergies?

    Microsoft Academic Search

    M. L. Cross; H. S. Gill

    2001-01-01

    Studies in gnotobiotic animals have suggested that the intestinal bacterial flora may play an important role in priming the immune system during ontogeny to limit dysfunctional responses, including allergy. Prospective clinical studies have identified a higher incidence of allergy expression in early childhood among children who have low enteric populations of lactic acid bacteria (LAB), such as lactobacilli and bifidobacteria,

  7. Survival of Lactic Acid Bacteria in the Human Stomach and Adhesion to Intestinal Cells

    Microsoft Academic Search

    P. L. Conway; S. L. Gorbach; B. R. Goldin

    1987-01-01

    The survival of four strains of lactic acid bacteria in human gastric juice, in vivo and in vitro, and in buffered saline, pH 1 to 5, has been investigated. The strains studied include two Lactobacillus acidophilus strains, Lactobacillus bul- garicus, and Streptococcus thermophilus. In addition, the adhesion of these strains to freshly collected human and pig small intestinal cells and

  8. Improved screening procedure for biogenic amine production by lactic acid bacteria

    Microsoft Academic Search

    Sara Bover-Cid; Wilhelm Heinrich Holzapfel

    1999-01-01

    An improved screening plate method for the detection of amino acid decarboxylase-positive microorganisms (especially lactic acid bacteria) was developed. The suitability and detection level of the designed medium were quantitatively evaluated by confirmation of amine-forming capacity using an HPLC procedure. The potential to produce the biogenic amines (BA) tyramine, histamine, putrescine, and cadaverine, was investigated in a wide number of

  9. RELATIONSHIP OF RUMEN GRAM-NEGATIVE BACTERIA AND FREE ENDOTOXIN TO LACTIC ACIDOSIS IN CATTLE x

    Microsoft Academic Search

    T. G. Nagaraja; E. E. Bartley; L. R. Fina; H. D. Anthony

    2010-01-01

    SUMMARY Feeding grain to animals not adapted to grain resulted in a marked increase in the .\\/ . concentration of free endotoxln m the rumen. Endotoxin concentration increased 15 to 18 times within 12 hr after lactic acidosis was induced through grain engorgement. The increase was accompanied by a shift from predominantly gram-negative to gram-positive bacteria. Data from in vitro

  10. Synthesis of  -Aminobutyric Acid by Lactic Acid Bacteria Isolated from a Variety of Italian Cheeses

    Microsoft Academic Search

    S. Siragusa; M. De Angelis; R. Di Cagno; C. G. Rizzello; R. Coda; M. Gobbetti

    2007-01-01

    The concentrations of -aminobutyric acid (GABA) in 22 Italian cheese varieties that differ in several technological traits markedly varied from 0.26 to 391 mg kg1. Presumptive lactic acid bacteria were isolated from each cheese variety (total of 440 isolates) and screened for the capacity to synthesize GABA. Only 61 isolates showed this activity and were identified by partial sequencing of

  11. Novel lactic acid bacteria inhibiting Paenibacillus larvae in honey bee larvae

    Microsoft Academic Search

    Eva Forsgren; Tobias C. Olofsson; Alejandra Váasquez; Ingemar Fries

    2010-01-01

    We evaluated the antagonistic effects of newly identified lactic acid bacteria (LAB) in the genera Lactobacillus and Bifidobacterium, originating from the honey stomach, on the honey bee pathogen, Paenibacillus larvae. We used inhibition assays on agar plates and honey bee larval bioassays to investigate the effects of honey bee LAB on P. larvae growth in vitro and on AFB infection

  12. Survival of probiotic bacteria during lactic acid fermentation of vegetable juices

    Microsoft Academic Search

    Carmen Leane Nicolescu; Daniela Avram; Magda Gabriela; Bratu Iuliana Manea

    The general objective of this research was to perform the lactic acid fermentative processes using different probiotic bacteria species unspecific to epiphytic microbiota of vegetables, with a view to achieve new knowledge concerning the possibility of developing and preservation their viability in vegetable juices. The carrots and the red beet were evaluated as potential substrat for the production of probiotic

  13. Functional properties of lactic acid bacteria isolated from ethnic fermented vegetables of the Himalayas

    Microsoft Academic Search

    Jyoti Prakash Tamang; Buddhiman Tamang; Ulrich Schillinger; Claudia Guigas; Wilhelm H. Holzapfel

    2009-01-01

    A total of 94 strains of Lactic acid bacteria (LAB), previously isolated from ethnic fermented vegetables and tender bamboo shoots of the Himalayas, were screened for functional properties such as acidification capacity, enzymatic activities, degradation of antinutritive factors and oligosaccharides, production of biogenic amines, hydrophobicity and adherence to mucus secreting HT29 MTX cells. Strong acidification and coagulation activities of LAB

  14. Effect of process parameters on the production of lactic acid bacteria in batch fermentation

    Microsoft Academic Search

    Emanuele ZANNINI; Sara SANTARELLI; Andrea OSIMANI; Luana DELL' AQUILA; Francesca CLEMENTI

    The effect of aeration and type of neutralising agent on the growth of lactic acid bacteria, isolated from a typical Italian cheese, was investigated in laboratory fermenters, with the aim of defining process conditions for the production of autochthonous cul- tures to be used as starters in traditional cheese-making. Batch fermentation trials were carried out using six different bacterial species

  15. Research on the adoption of Lactic acid bacteria in food waste storage and ethanol production

    Microsoft Academic Search

    Wenyu Zhang; Hongzhi Ma; Qunhui Wang; Jiale Xia

    2012-01-01

    The preservation and deodorization of food waste are very important for its utilization in fuel ethanol production as raw materials. In this paper the inoculation of lactic acid bacteria (LAB) was carried out for food waste storage and its further fermentation for ethanol. Four contamination prevention methods, anaerobic storage, autoclaving, acid usage, the inoculation of LAB were compared in this

  16. Metatranscriptome analysis of lactic acid bacteria during kimchi fermentation with genome-probing microarrays

    Microsoft Academic Search

    Young-Do Nam; Ho-Won Chang; Kyoung-Ho Kim; Seong Woon Roh; Jin-Woo Bae

    2009-01-01

    We constructed genome probing microarrays (GPM) that are specific to 39 lactic acid bacteria (LAB) in an effort to monitor microbial diversity and biological activity during the fermentation of kimchi, a traditional Korean vegetable product known to contain various health-promoting and immunity-boosting factors. Metagenomes and metatranscriptomes extracted from periodically sampled kimchi soup were labeled, hybridized and comparatively analyzed using GPMs.

  17. Phenotypic and Genotypic Characterization of Lactic Acid Bacteria Isolated from Some Nigerian Traditional Fermented Foods

    Microsoft Academic Search

    Kolawole Banwo; Abiodun Sanni; Huarong Tan; Yuqing Tian

    2012-01-01

    A total of 104 lactic acid bacteria were isolated from ogi, wara, fermenting cassava mash for local food product gari and raw milk for nono. They were characterized phenotypically and divided into six main groups, which are facultative heterofermentative rods, obligate heterofermentative rods, tetrad-forming homofermentative cocci, homofermentative cocci, heterofermentative cocci, and an unidentified group. A total of 40 strains with

  18. EXTERNAL TREATMENT OF BROILER CHICKENS WITH LACTIC ACID BACTERIA BEFORE SLAUGHTER

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Lactic-acid-producing bacterial cultures were applied to the skin of live broilers 24 hours before slaughter to determine whether inoculation with the cultures could affect the numbers of bacteria that are normally found on the skin of processed broiler carcasses. The cultures contained 10,000 to 1...

  19. Nonstarter Lactic Acid Bacteria and Aging Temperature Affect Calcium Lactate Crystallization in Cheddar Cheese

    Microsoft Academic Search

    Y.-E. Chou; C. G. Edwards; L. O. Luedecke; M. P. Bates; S. Clark

    2003-01-01

    The occurrence of unappetizing calcium lactate crys- tals in Cheddar cheese is a challenge and expense to manufacturers, and this research was designed to un- derstand their origin. It was hypothesized that non- starter lactic acid bacteria (NSLAB) affect calcium lac- tate crystallization (CLC) by producing D(?)-lactate. This study was designed to understand the effect of NSLAB growth and aging

  20. Tyramine degradation and tyramine\\/histamine production by lactic acid bacteria and Kocuria strains

    Microsoft Academic Search

    S. Fadda; G. Vignolo; G. Oliver

    2001-01-01

    Of 53 strains of lactic acid bacteria and Kocuria, screened for production or degradation of biogenic amines, 29 Kocuria varians and four strains of Enterococcusfaecalisproduced tyramine and, at lower concentrations, histamine. In contrast, Lactobacillus strains that did not possess amino acid decarboxylase activity degraded tyramine. The greatest tyramine oxidase activity was present in the strains L. casei CRL705 (98% degradation)

  1. Isolation, Characterization, and Influence of Native, Nonstarter Lactic Acid Bacteria on Cheddar Cheese Quality1

    Microsoft Academic Search

    P. A. Swearingen; D. J. O'Sullivan; J. J. Warthesen

    2001-01-01

    To determine whether adventitious nonstarter lactic acid bacteria (NSLAB) might affect cheese flavor and quality, we studied a population of NSLAB present in 30 premium quality Cheddar cheeses (3-mo ripened) pro- duced at a commercial facility in the United States. DNA fingerprinting analysis with a sensitive strategy for arbi- trary priming polymerase chain reaction showed that 75 isolates corresponded to

  2. Biodiversity of lactic acid bacteria in Moroccan soft white cheese (Jben)

    Microsoft Academic Search

    Mouna Ouadghiri; Mohamed Amar; Marc Vancanneyt; Jean Swings

    2005-01-01

    The bacterial diversity occurring in traditional Moroccan soft white cheese, produced in eight different regions in Morocco, was studied. A total of 164 lactic acid bacteria were isolated, purified and identified by whole-cell protein fingerprinting and rep-PCR genomic fingerprinting. The majority of the strains belonged to the genera Lactobacillus, Lactococcus, Leuconostoc and Enterococcus. Sixteen species were identified: Lactobacillus plantarum, Lactobacillus

  3. Influences of lactic acid bacteria on technological, nutritional, and sensory properties of barley sour dough bread

    Microsoft Academic Search

    Ingela Marklinder; Åsa Haglund; Lisbeth Johansson

    1996-01-01

    Barley bread was baked with and without admixture of barley sour doughs, individually fermented with seven starter cultures containing lactic acid bacteria (including two with ?-glucanase activity).The aim of the study was to investigate how starter cultures influenced the baking-technological, nutritional and sensory properties of barley bread. Could degradation of ?-glucans caused by sour dough admixture result in bread that

  4. The Phylogenetic Diversity of Aerobic Organotrophic Bacteria from the Dagang High-Temperature Oil Field

    Microsoft Academic Search

    T. N. Nazina; D. Sh. Sokolova; N. M. Shestakova; A. A. Grigoryan; E. M. Mikhailova; T. L. Babich; A. M. Lysenko; T. P. Tourova; A. B. Poltaraus; Qingxian Feng; Fangtian Ni; S. S. Belyaev

    2005-01-01

    The distribution and species diversity of aerobic organotrophic bacteria in the Dagang high-temperature oil field (China), which is exploited with water-flooding, have been studied. Twenty-two strains of the most characteristic thermophilic and mesophilic aerobic organotrophic bacteria have been isolated from the oil stratum. It has been found that, in a laboratory, the mesophilic and thermophilic isolates grow in the temperature,

  5. Lactic acid bacteria in the quality improvement and depreciation of wine.

    PubMed

    Lonvaud-Funel, A

    1999-01-01

    The winemaking process includes two main steps: lactic acid bacteria are responsible for the malolactic fermentation which follows the alcoholic fermentation by yeasts. Both types of microorganisms are present on grapes and on cellar equipment. Yeasts are better adapted to growth in grape must than lactic acid bacteria, so the alcoholic fermentation starts quickly. In must, up to ten lactic acid bacteria species can be identified. They belong to the Lactobacillus, Pediococcus, Leuconostoc and Oenococcus genera. Throughout alcoholic fermentation, a natural selection occurs and finally the dominant species is O. oeni, due to interactions between yeasts and bacteria and between bacteria themselves. After bacterial growth, when the population is over 10(6) CFU/ml, malolactic transformation is the obvious change in wine composition. However, many other substrates can be metabolized. Some like remaining sugars and citric acid are always assimilated by lactic acid bacteria, thus providing them with energy and carbon. Other substrates such as some amino acids may be used following pathways restricted to strains carrying the adequate enzymes. Some strains can also produce exopolysaccharides. All these transformations greatly influence the sensory and hygienic quality of wine. Malic acid transformation is encouraged because it induces deacidification. Diacetyl produced from citric acid is also helpful to some extent. Sensory analyses show that many other reactions change the aromas and make malolactic fermentation beneficial, but they are as yet unknown. On the contrary, an excess of acetic acid, the synthesis of glucane, biogenic amines and precursors of ethylcarbamate are undesirable. Fortunately, lactic acid bacteria normally multiply in dry wines; moreover some of these activities are not widespread. Moreover, the most striking trait of wine lactic acid bacteria is their capacity to adapt to a hostile environment. The mechanisms for this are not yet completely elucidated. Molecular biology has provided some explanations for the behaviour and the metabolism of bacteria in wine. New tools are now available to detect the presence of desirable and undesirable strains. Even if much remains unknown, winemakers and oenologists can nowadays better control the process. By acting upon the diverse microflora and grape musts, they are more able to produce healthy and pleasant wines. PMID:10532386

  6. Organism-Adapted Specificity of the Allosteric Regulation of Pyruvate Kinase in Lactic Acid Bacteria

    PubMed Central

    Veith, Nadine; Feldman-Salit, Anna; Cojocaru, Vlad; Henrich, Stefan; Kummer, Ursula; Wade, Rebecca C.

    2013-01-01

    Pyruvate kinase (PYK) is a critical allosterically regulated enzyme that links glycolysis, the primary energy metabolism, to cellular metabolism. Lactic acid bacteria rely almost exclusively on glycolysis for their energy production under anaerobic conditions, which reinforces the key role of PYK in their metabolism. These organisms are closely related, but have adapted to a huge variety of native environments. They include food-fermenting organisms, important symbionts in the human gut, and antibiotic-resistant pathogens. In contrast to the rather conserved inhibition of PYK by inorganic phosphate, the activation of PYK shows high variability in the type of activating compound between different lactic acid bacteria. System-wide comparative studies of the metabolism of lactic acid bacteria are required to understand the reasons for the diversity of these closely related microorganisms. These require knowledge of the identities of the enzyme modifiers. Here, we predict potential allosteric activators of PYKs from three lactic acid bacteria which are adapted to different native environments. We used protein structure-based molecular modeling and enzyme kinetic modeling to predict and validate potential activators of PYK. Specifically, we compared the electrostatic potential and the binding of phosphate moieties at the allosteric binding sites, and predicted potential allosteric activators by docking. We then made a kinetic model of Lactococcus lactis PYK to relate the activator predictions to the intracellular sugar-phosphate conditions in lactic acid bacteria. This strategy enabled us to predict fructose 1,6-bisphosphate as the sole activator of the Enterococcus faecalis PYK, and to predict that the PYKs from Streptococcus pyogenes and Lactobacillus plantarum show weaker specificity for their allosteric activators, while still having fructose 1,6-bisphosphate play the main activator role in vivo. These differences in the specificity of allosteric activation may reflect adaptation to different environments with different concentrations of activating compounds. The combined computational approach employed can readily be applied to other enzymes. PMID:23946717

  7. Inhibition of food-borne bacterial pathogens by bacteriocins from lactic acid bacteria isolated from meat.

    PubMed Central

    Lewus, C B; Kaiser, A; Montville, T J

    1991-01-01

    Ten strains of bacteriocin-producing lactic acid bacteria were isolated from retail cuts of meat. These 10 strains along with 11 other bacteriocin-producing lactic acid bacteria were tested for inhibitory activity against psychotrophic pathogens, including four strains of Listeria monocytogenes, two strains of Aeromonas hydrophila, and two strains of Staphylococcus aureus. Inhibition due to acid, hydrogen peroxide, and lytic bacteriophage were excluded. The proteinaceous nature of the inhibitory substance was confirmed by demonstration of its sensitivity to proteolytic enzymes. Eight of the meat isolates had inhibitory activity against all four L. monocytogenes strains. Bacteriocin activity against L. monocytogenes was found in all of the strains obtained from other sources. Activity against A. hydrophila and S. aureus was also common. Images PMID:1908209

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

    PubMed Central

    Kaur, Baljinder; Kumar, Balvir

    2013-01-01

    Vanillin is widely used as food additive and as a masking agent in various pharmaceutical formulations. Ferulic acid is an important precursor of vanillin that is available in abundance in cell walls of cereals like wheat, corn, and rice. Phenolic biotransformations can occur during growth of lactic acid bacteria (LAB), and their production can be made feasible using specialized LAB strains that have been reported to produce ferulic acid esterases. The present study aimed at screening a panel of LAB isolates for their ability to release phenolics from agrowaste materials like rice bran and their biotransformation to industrially important compounds such as ferulic acid, 4-ethyl phenol, vanillic acid, vanillin, and vanillyl alcohol. Bacterial isolates were evaluated using ferulic acid esterase, ferulic acid decarboxylase, and vanillin dehydrogenase assays. This work highlights the importance of lactic acid bacteria in phenolic biotransformations for the development of food grade flavours and additives. PMID:24066293

  9. Amino acid profiles of lactic acid bacteria, isolated from kefir grains and kefir starter made from them

    Microsoft Academic Search

    Emilina Simova; Zhelyasko Simov; Dora Beshkova; Ginka Frengova; Zhechko Dimitrov; Zdravko Spasov

    2006-01-01

    The characteristics of cell growth, lactic acid production, amino acid release and consumption by single-strain cultures of lactic acid bacteria (isolated from kefir grains), and by a multiple-strain kefir starter prepared from them, were studied. The change in the levels of free amino acids was followed throughout the kefir process: single-strain kefir bacteria and the kefir starter (Lactococcus lactis C15–1%+Lactobacillus

  10. Evaluation of Anti-colitic Effect of Lactic Acid Bacteria in Mice by cDNA Microarray Analysis

    Microsoft Academic Search

    Hoyong Lee; Young-Tae Ahn; Jung-Hee Lee; Chul-Sung Huh; Dong-Hyun Kim

    2009-01-01

    To evaluate the anti-colitic effect of lactic acid bacteria by cDNA microarray analysis, a lactic acid bacteria mixture (LM)\\u000a consisting of Lactobacillus brevis HY7401, L. suntoryeus HY7801 and Bifidobacterium longum HY8004 was orally administered to dextran sulfate (DSS)-induced colitic mice and the expression profile of numerous genes\\u000a was assessed. DSS treatment caused colitic outcomes such as inflammation and colon shortening.

  11. Fermented Milk–Starch and Milk–Inulin Products as Vehicles for Lactic Acid Bacteria

    Microsoft Academic Search

    ANGELA ZULETA; MARÍA I. SARCHI; MARÍA E. RIO; MARÍA E. SAMBUCETTI; MARCELO MORA; SUSANA V. DE FABRIZIO; JOSÉ L. PARADA

    2004-01-01

    Formulations using cassava starch or inulin plus milk were fermented with three different lactic acid bacteria (LAB) strains: Lactobacillus plantarum D34, Lactobacillus sp. SLH6, and Streptococcus thermophilus ST4. Growth and acidification were followed in 3% powdered milk (M3), 3% milk–6% starch (M3-S6), and 3% milk–6% inulin (M3-In6). D34 and SLH6 growth was enhanced by starch in M3-S6, when compared to

  12. Interaction between lactic acid bacteria and yeasts in sour-dough using a rheofermentometer

    Microsoft Academic Search

    M. Gobbetti; A. Corsetti; J. Rossi

    1995-01-01

    Rheofermentometer assays were used to characterize the leavening of sour-doughs produced using species of lactic acid bacteria (LAB) and yeasts, alone or in combination. Saccharomyces cerevisiae 141 produced the most CO2 and ethanol whereas S. exiguus M14 and Lactobacillus brevis subsp. lindneri CB1 contributed poorly to leavening and gave sour-doughs without porosity. In comparison with that seen in sour-dough produced

  13. Novel multiplex PCR for the detection of lactic acid bacteria during kimchi fermentation

    Microsoft Academic Search

    Kye Man Cho; Woo Jin Lim; Su Young Hong; Jong Min Kim; Myoung Geun Yun; Ji Joong Cho; Han Dae Yun

    2009-01-01

    We developed a multiplex PCR assay for the detection of lactic acid bacteria (LAB) species, and used it to examine the LAB species involved in kimchi fermentation. The LAB profile during kimchi fermentation varied with pH and acidity. Leuconostoc mesenteroides was observed during early fermentation (pH 5.64–4.27 and acidity 0.48–0.89%), and Lactobacillus sakei become dominant later in fermentation (pH ?4.15

  14. Distribution and genetic diversity of lactic acid bacteria from traditional fermented sausage

    Microsoft Academic Search

    Khanh T. M. Tran; Bee K. May; Peter M. Smooker; Thi T. H. Van; Peter J. Coloe

    2011-01-01

    This study was conducted to investigate the distribution and genetic diversity of the native lactic acid bacteria (LAB) population in nem chua, a popular traditional Vietnamese uncooked fermented sausage. A total of 74 LAB isolates were identified and their molecular fingerprints were obtained using repetitive-PCR (rep-PCR) and pulse-field gel electrophoresis (PFGE). The results revealed that the majority of LAB isolates

  15. Biogenic amines in cold-smoked fish fermented with lactic acid bacteria

    Microsoft Academic Search

    E. Petäjä; S. Eerola; P. Petäjä

    2000-01-01

    It has been proved in previous studies that fish can be fermented by lactic acid bacteria (LAB). Added glucose must be at\\u000a concentrations of almost 1% to reduce the pH to <5.3, a level which corresponds to the safe pH values for meat products. Because\\u000a some LAB and some contaminating microbes form biogenic amines, this study was conducted to examine

  16. Isolation and Partial Characterization of Halotolerant Lactic Acid Bacteria from Two Mexican Cheeses

    Microsoft Academic Search

    Fredy Morales; Jesús I. Morales; César H. Hernández; Humberto Hernández-Sánchez

    2011-01-01

    Isolated strains of halotolerant or halophilic lactic acid bacteria (HALAB) from Cotija and doble crema cheeses were identified and partially characterized by phenotypic and genotypic methods, and their technological abilities\\u000a were studied in order to test their potential use as dairy starter components. Humidity, aw, pH, and salt concentration of cheeses were determined. Genotypic diversity was evaluated by randomly amplified

  17. Inhibition of aflatoxin-producing aspergilli by lactic acid bacteria isolates from indigenously fermented cereal gruels

    Microsoft Academic Search

    A. A. Onilude; O. E. Fagade; M. M. Bello; I. F. Fadahunsi

    A total of six lactic acid bacteria (LAB) isolates were selected from five indigenously fermented cereal gruels and identified as Lactobacillus fermentum OYB, Lb. fermentum RS2, Lb. plantarum MW, Lb. plantarum YO, Lb. brevis WS3, and Lactococcus spp. RS3. Six aflatoxin-producing aspergilli were also selected from the various food sources. Two of the isolates, identified as Aspergillus parasiticus C2 and

  18. Characterization and Transfer of Antibiotic Resistance in Lactic Acid Bacteria from Fermented Food Products

    Microsoft Academic Search

    Muhammad Nawaz; Juan Wang; Aiping Zhou; Chaofeng Ma; Xiaokang Wu; John E. Moore; B. Cherie Millar; Jiru Xu

    2011-01-01

    The study provides phenotypic and molecular analyses of the antibiotic resistance in lactic acid bacteria (LAB) from fermented\\u000a foods in Xi’an, China. LAB strains (n = 84) belonging to 16 species of Lactobacillus (n = 73), and Streptococcus thermophilus (n = 11) were isolated and identified by sequencing their 16S rRNA gene. All strains were susceptible to ampicillin, bacitracin,\\u000a and cefsulodin, and intrinsically resistant to nalidixic

  19. Use of the alr gene as a food-grade selection marker in lactic acid bacteria

    Microsoft Academic Search

    Peter A. Bron; Marcos G. Benchimol; Jolanda Lambert; Emmanuelle Palumbo; Marie Deghorain; Jean Delcour; Vos de W. M; Michiel Kleerebezem; Pascal Hols

    2002-01-01

    Both Lactococcus lactis and Lactobacillus plantarum contain a single alr gene, encoding an alanine racemase (EC 5.1.1.1), which catalyzes the interconversion of D-alanine and L-alanine. The alr genes of these lactic acid bacteria were investigated for their application as food-grade selection markers in a heterologous complementation approach. Since isogenic mutants of both species carrying an alr deletion (alr) showed auxotrophy

  20. Detection and Characterization of Pediocin PA1\\/AcH like Bacteriocin Producing Lactic Acid Bacteria

    Microsoft Academic Search

    S. Manjulata Devi; Prakash M. Halami

    2011-01-01

    Fifty-five bacteriocinogenic lactic acid bacteria (LAB) isolated from seven different sources. Eight isolates were found to\\u000a produce pediocin PA-1 like bacteriocin as detected by pedB gene PCR and dot-blot hybridization. The culture filtrate (CF) activity of these isolates exhibited strong antilisterial,\\u000a antibacterial activity against tested food-borne pathogens and LAB. The identification and genetic diversity among the selected\\u000a LAB was performed

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

    Microsoft Academic Search

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

    2010-01-01

    The lactic acid bacteria (LAB) play an important role in the fermentation of vegetables to improve nutritive value, palatability,\\u000a acceptability, microbial quality and shelf life of the fermented produce. The LAB associated with beetroot and carrot fermentation\\u000a were identified and characterized using different molecular tools. Amplified ribosomal DNA restriction analysis (ARDRA) provided\\u000a similar DNA profile for the 16 LAB strains

  2. Evaluation of the Probiotic Characteristics of Newly Isolated Lactic Acid Bacteria

    Microsoft Academic Search

    Ravindran Girija Aswathy; Bindhumol Ismail; Rojan Pappy John; Kesavan Madhavan Nampoothiri

    2008-01-01

    Lactic acid bacteria were isolated from fermented vegetables, sour dough, milk products, sheep and human excreta. The newly\\u000a isolated cultures were evaluated for a number of probiotic characteristics like bile salt resistance, salt tolerance in general,\\u000a survival in low pH, hydrophobicity of the cell surface, resistance to low phenol concentration, antimicrobial activity and\\u000a susceptibility pattern against vancomycin and erythromycin. The

  3. Anti-allergic effect of Petasites japonicus fermented with lactic acid bacteria in mice

    Microsoft Academic Search

    Eun-Ah Bae; Hien-Trung Trinh; Yun-Ah Jang; Hyung-Kwon Yun; Seong-Sig Hong; Dong-Hyun Kim

    2009-01-01

    Petasites japonicus (PJ, family Asteraceae) was fermented with lactic acid bacteria (LAB), Bifidobacterium breve (BB) or Lactobacillus acidophilus (LA), and its allergic effect was investigated. LAB-fermented PJs more potently inhibited IgE–antigen-stimulated degranulation of RBL-2H3 cells than non-fermented PJ, with BB-fermented PJ more potent than LA-fermented PJ. Fermented PJ more potently inhibited TNF-? and IL-4 cytokine expression and transcription factor NF-?B

  4. Decolorization of molasses melanoidins and palm oil mill effluent phenolic compounds by fermentative lactic acid bacteria

    Microsoft Academic Search

    Vassanasak Limkhuansuwan; Pawinee Chaiprasert

    2010-01-01

    Lactobacillus plantarum SF5.6 is one of the lactic acid bacteria (LAB) that has the highest ability of molasses melanoidin (MM) decolorization among the 2114 strains of LAB. The strains were isolated from spoilage, pickle fruit and vegetable, soil and sludge from the wastewater treatment system by using technical step of enrichment, primary screening and secondary screening. This LAB strain SF5.6

  5. Identification of Lactic Acid Bacteria from Chili Bo, a Malaysian Food Ingredient

    Microsoft Academic Search

    JØRGEN J. LEISNER; BRUNO POT; HENRIK CHRISTENSEN; GULAM RUSUL; JOHN E. OLSEN; BEE WAH WEE; KHARIDAH MUHAMAD; HASANAH M. GHAZALI

    1999-01-01

    Ninety-two strains of lactic acid bacteria (LAB) were isolated from a Malaysian food ingredient, chili bo, stored for up to 25 days at 28°C with no benzoic acid (product A) or with 7,000 mg of benzoic acid kg21 (product B). The strains were divided into eight groups by traditional phenotypic tests. A total of 43 strains were selected for comparison

  6. ISOLATION AND CHARACTERIZATION OF HALOTOLERANT AEROBIC BACTERIA FROM OIL RESERVOIR

    Microsoft Academic Search

    ROSLI M. D. ILLIAS; OOI SEOK WEI; AHMAD KAMAL IDRIS; WAN AIZAN; WAN ABDUL

    Several halotolerant bacteria were isolated from brine samples from Semangkok oil reservoir. Biochemical and morphological characterization of the bacteria were carried out. These bacteria are gram positive spore formers and have been identified as belonging to the genus Bacillus. Most of the isolates could grow in medium containing kerosene as sole carbon source and energy and tolerate NaCl concentration up

  7. Genetically modified lactic acid bacteria: applications to food or health and risk assessment.

    PubMed

    Renault, Pierre

    2002-11-01

    Lactic acid bacteria have a long history of use in fermented food products. Progress in gene technology allows their modification by introducing new genes or by modifying their metabolic functions. These modifications may lead to improvements in food technology (bacteria better fitted to technological processes, leading to improved organoleptic properties em leader ), or to new applications including bacteria producing therapeutic molecules that could be delivered by mouth. Examples in these two fields will be discussed, at the same time evaluating their potential benefit to society and the possible risks associated with their use. Risk assessment and expected benefits will determine the future use of modified bacteria in the domains of food technology and health. PMID:12595135

  8. Role of malolactic fermentation in lactic acid bacteria.

    PubMed

    Renault, P; Gaillardin, C; Heslot, H

    1988-03-01

    Although decarboxylation of malate to lactate by malolactic enzyme does not liberate biologically available energy (e.g., ATP, NADH), the growth rate of many malolactic bacteria is greatly enhanced by malolactic fermentation. The deacidification of the medium due to malate dissipation cannot fully account for this situation. The chemiosmotic theory postulates that another form of energy could generated by translocation of protons through the membrane coupled to end-product efflux. Konings et al. showed that this theory is indeed applicable to lactate efflux in Streptococcus cremoris at pH 7.0. A similar mechanism could account for the observed increased activity in malolactic bacteria. The study in wild type and mutant strains of Streptococcus lactis unable to carry out malolactic fermentation led us to the following conclusions: (1) under glucose non-limiting conditions, malolactic fermentation helps to maintain pH of the medium at a certain level; (2) during glucose limited growth, malolactic fermentation could be coupled with an energetic process independent from that mentioned above. PMID:3139055

  9. Inhibition of spoilage and food-borne pathogens by lactic acid bacteria isolated from fermenting tef (Eragrostis tef) dough.

    PubMed

    Nigatu, A; Gashe, B A

    1994-10-01

    A study was carried out at the Department of Biology, Addis Abeba University, in 1991 to determine the inhibitory potential of fermenting tef and the lactic acid bacteria isolated from fermenting tef dough on Salmonella spp., Pseudomonas aeruginosa, Klebsiella spp., Bacillus cereus and Staphylococcus aureus. The test bacteria grew in the fermenting tef uptill 30 hr or till the pH dropped to 4.7. Thereafter, growth was inhibited and decreases in population were apparent. The results showed that the spent media from all of the four lactic acid bacterial isolates, namely, Lactobacillus spp., Pediococcus spp., Leuconostoc spp. and Streptococcus spp. inhibited the test bacteria. Acidity on its own was not responsible for the inhibition of the test bacteria. The spent medium from Streptococcus spp. showed the best inhibitory activity amongst the lactic acid bacteria. PMID:7835350

  10. Comparison of dry medium culture plates for mesophilic aerobic bacteria in milk, ice cream, ham, and codfish fillet products.

    PubMed

    Park, Junghyun; Kim, Myunghee

    2013-12-01

    This study was performed to compare the performance of Sanita-Kun dry medium culture plate with those of traditional culture medium and Petrifilm dry medium culture plate for the enumeration of the mesophilic aerobic bacteria in milk, ice cream, ham, and codfish fillet. Mesophilic aerobic bacteria were comparatively evaluated in milk, ice cream, ham, and codfish fillet using Sanita-Kun aerobic count (SAC), Petrifilm aerobic count (PAC), and traditional plate count agar (PCA) media. According to the results, all methods showed high correlations of 0.989~1.000 and no significant differences were observed for enumerating the mesophilic aerobic bacteria in the tested food products. SAC method was easier to perform and count colonies efficiently as compared to the PCA and PAC methods. Therefore, we concluded that the SAC method offers an acceptable alternative to the PCA and PAC methods for counting the mesophilic aerobic bacteria in milk, ice cream, ham, and codfish fillet products. PMID:24551829

  11. Isolation of thermophilic L-lactic acid producing bacteria showing homo-fermentative manner under high aeration condition.

    PubMed

    Tongpim, Saowanit; Meidong, Ratchanu; Poudel, Pramod; Yoshino, Satoshi; Okugawa, Yuki; Tashiro, Yukihiro; Taniguchi, Masayuki; Sakai, Kenji

    2014-03-01

    By applying non-sterile open fermentation of food waste, various thermotolerant l-lactic acid-producing bacteria were isolated and identified. The predominant bacterial isolates showing higher accumulation of l-lactic acid belong to 3 groups of Bacillus coagulans, according to their 16S rRNA gene sequence similarities. B. coagulans strains M21 and M36 produced high amounts of l-lactic acid of high optical purity and lactic acid selectivity in model kitchen refuse medium and glucose-yeast extract-peptone medium. Other thermotolerant isolates resembling to Bacillus humi, B. ruris, B. subtilis, B. niacini and B. soli were also identified. These bacteria produced low amounts of l-lactic acid of more than 99% optical purity. All isolated strains showed the highest growth rate at temperatures around 55-60°C. They showed unique responses to various oxygen supply conditions. The majority of isolates produced l-lactic acid at a low overall oxygen transfer coefficient (KLa); however, acetic acid was produced instead of l-lactic acid at a high KLa. B. coagulans M21 was the only strain that produced high, consistent, and reproducible amounts of optically pure l-lactic acid (>99% optical purity) under high and low KLa conditions in a homo-fermentative manner. PMID:24119530

  12. Phenotypic and genotypic characterization of some lactic Acid bacteria isolated from bee pollen: a preliminary study.

    PubMed

    Belhadj, Hani; Harzallah, Daoud; Bouamra, Dalila; Khennouf, Seddik; Dahamna, Saliha; Ghadbane, Mouloud

    2014-01-01

    In the present work, five hundred and sixty-seven isolates of lactic acid bacteria were recovered from raw bee pollen grains. All isolates were screened for their antagonistic activity against both Gram-positive and Gram-negative pathogenic bacteria. Neutralized supernatants of 54 lactic acid bacteria (LAB) cultures from 216 active isolates inhibited the growth of indicator bacteria. They were phenotypically characterized, based on the fermentation of 39 carbohydrates. Using the simple matching coefficient and unweighted pair group algorithm with arithmetic averages (UPGMA), seven clusters with other two members were defined at the 79% similarity level. The following species were characterized: Lactobacillus plantarum, Lactobacillus fermentum, Lactococcus lactis, Pediococcus acidilactici, Pediococcus pentosaceus, and unidentified lactobacilli. Phenotypic characteristics of major and minor clusters were also identified. Partial sequencing of the 16S rRNA gene of representative isolates from each cluster was performed, and ten strains were assigned to seven species: Lactobacillus plantarum, Lactobacillus fermentum, Lactococcus lactis, Lactobacillus ingluviei, Pediococcus pentosaceus, Lactobacillus acidipiscis and Weissella cibaria. The molecular method used failed to determine the exact taxonomic status of BH0900 and AH3133. PMID:24936378

  13. Phenotypic and Genotypic Characterization of Some Lactic Acid Bacteria Isolated from Bee Pollen: A Preliminary Study

    PubMed Central

    BELHADJ, Hani; HARZALLAH, Daoud; BOUAMRA, Dalila; KHENNOUF, Seddik; Dahamna, Saliha; GHADBANE, Mouloud

    2014-01-01

    In the present work, five hundred and sixty-seven isolates of lactic acid bacteria were recovered from raw bee pollen grains. All isolates were screened for their antagonistic activity against both Gram-positive and Gram-negative pathogenic bacteria. Neutralized supernatants of 54 lactic acid bacteria (LAB) cultures from 216 active isolates inhibited the growth of indicator bacteria. They were phenotypically characterized, based on the fermentation of 39 carbohydrates. Using the simple matching coefficient and unweighted pair group algorithm with arithmetic averages (UPGMA), seven clusters with other two members were defined at the 79% similarity level. The following species were characterized: Lactobacillus plantarum, Lactobacillus fermentum, Lactococcus lactis, Pediococcus acidilactici, Pediococcus pentosaceus, and unidentified lactobacilli. Phenotypic characteristics of major and minor clusters were also identified. Partial sequencing of the 16S rRNA gene of representative isolates from each cluster was performed, and ten strains were assigned to seven species: Lactobacillus plantarum, Lactobacillus fermentum, Lactococcus lactis, Lactobacillus ingluviei, Pediococcus pentosaceus, Lactobacillus acidipiscis and Weissella cibaria. The molecular method used failed to determine the exact taxonomic status of BH0900 and AH3133. PMID:24936378

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

    PubMed Central

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

    2013-01-01

    Objective To determine lactic acid bacteria's capability to enhance the process of binding and isolating aflatoxin B1 and to utilize such lactic acid bacteria as a food supplement or probiotic products for preventing absorption of aflatoxin B1 in human and animal bodies. Methods In the present research, the bacteria were isolated from five different sources. For surveying the capability of the bacteria in isolating aflatoxin B1, ELISA method was implemented, and for identifying the resultant strains through 16S rRNA sequencing method, universal primers were applied. Results Among the strains which were isolated, two strains of Lactobacillus pentosus and Lactobacillus beveris exhibited the capability of absorbing and isolating aflatoxin B1 by respectively absorbing and discharging 17.4% and 34.7% of the aforementioned toxin existing in the experiment solution. Conclusions Strains of Lactobacillus pentosus and Lactobacillus beveris were isolated from human feces and local milk samples, respectively. And both strains has the ability to isolate or bind with aflatoxin B1. PMID:23998015

  15. Developments in the Taxonomy of Aerobic, Endospore-forming Bacteria

    Microsoft Academic Search

    Niall A. Logan; Gillian Halket

    \\u000a \\u000a Bacillus holds an important place in the history of bacteriology. With observations upon Bacillus subtilis and its spores Cohn discredited the theory of spontaneous generation, and with his demonstration of the life history of B. anthracis in 1876 Robert Koch proved the germ theory of disease and founded medical bacteriology. Later, Bacillus became defined as a genus of aerobic, endospore-forming

  16. Heterotrophic nitrification–aerobic denitrification by novel isolated bacteria

    Microsoft Academic Search

    Qian Chen; Jinren Ni

    Three novel strains capable of heterotrophic nitrification–aerobic denitrification were isolated from the landfill leachate\\u000a treatment system. Based on their phenotypic and phylogenetic characteristics, the isolates were identified as Agrobacterium sp. LAD9, Achromobacter sp. GAD3 and Comamonas sp. GAD4, respectively. Batch tests were carried out to evaluate the growth and the ammonia removal patterns. The maximum\\u000a growth rates as determined from

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

    PubMed

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

    2014-01-01

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

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

    PubMed Central

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

    2014-01-01

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

  19. Interaction between probiotic lactic acid bacteria and canine enteric pathogens: a risk factor for intestinal Enterococcus faecium colonization?

    Microsoft Academic Search

    Minna Rinkinen; Katri Jalava; Elias Westermarck; Seppo Salminen; Arthur C Ouwehand

    2003-01-01

    Selected probiotic lactic acid bacteria (LAB) have been shown to elicit positive health effects particularly in humans. Competitive exclusion of pathogens is one of the most important beneficial health claims of probiotic bacteria. The effect of probiotic LAB on competitive exclusion of pathogens has been demonstrated in humans, chicken and pigs. In this study we evaluated the ability of certain

  20. Spontaneous organic cocoa bean box fermentations in Brazil are characterized by a restricted species diversity of lactic acid bacteria and acetic acid bacteria

    Microsoft Academic Search

    Zoi Papalexandratou; Gino Vrancken; Katrien De Bruyne; Peter Vandamme; Luc De Vuyst

    2011-01-01

    Spontaneous organic cocoa bean box fermentations were carried out on two different farms in Brazil. Physical parameters, microbial growth, bacterial species diversity [mainly lactic acid bacteria (LAB) and acetic acid bacteria (AAB)], and metabolite kinetics were monitored, and chocolates were produced from the fermented dry cocoa beans. The main end-products of the catabolism of the pulp substrates (glucose, fructose, and

  1. Space agriculture for habitation on Mars with hyper-thermophilic aerobic composting bacteria

    Microsoft Academic Search

    S. Kanazawa; Y. Ishikawa; K. Tomita-Yokotani; H. Hashimoto; Y. Kitaya; M. Yamashita; M. Nagatomo; T. Oshima; H. Wada

    2008-01-01

    Manned Mars exploration, especially for extended periods of time, will require recycle of materials to support human life. Here, a conceptual design is developed for a Martian agricultural system driven by biologically regenerative functions. One of the core biotechnologies function is the use of hyper-thermophilic aerobic composting bacterial ecology. These thermophilic bacteria can play an important role in increasing the

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

    PubMed

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

    2009-01-01

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

  3. Lipoquinones of some spore-forming rods, lactic-acid bacteria and actinomycetes.

    PubMed

    Hess, A; Holländer, R; Mannheim, W

    1979-11-01

    The respiratory quinones of 73 strains of Gram-positive bacteria including spore-forming rods, lactic-acid bacteria and actinomyctes were examined. Menaquinones with seven isoprenoid units (MK-7) were the main quinone type found in representatives of the genus Bacillus and in Sporolactobacillus inulinus. However, a strain of B. thuringiensis produced MK-8 in addition to MK-7, and strains of B. lentus and B. pantothenticus appeared to produce MK-9 and MK-8, respectively, with no MK-7. In the clostridia and lactic-acid bacteria, no quinones were found, except in Pediococcus cerevisiae NCTC 8066 and Lactobacillus casei subsp. rhamnosus ATCC 7469, which contained menaquinones, and Streptococcus faecalis NCTC 775 and HIM 478-1, which contained demethylmenaquinones, in relatively low concentrations. Menaquinones were also found in the actinomycetes (except Actinomyces odontolyticus and Bifidobacterium bifidum which did not produce any quinones) and in Protaminobacter alboflavus ATCC 8458, the so-called Actinobacillus actinoides ATCC 15900 and Noguchia granulosis NCTC 10559. PMID:119033

  4. A Glutamic Acid-Producing Lactic Acid Bacteria Isolated from Malaysian Fermented Foods

    PubMed Central

    Zareian, Mohsen; Ebrahimpour, Afshin; Bakar, Fatimah Abu; Mohamed, Abdul Karim Sabo; Forghani, Bita; Ab-Kadir, Mohd Safuan B.; Saari, Nazamid

    2012-01-01

    l-glutamaic acid is the principal excitatory neurotransmitter in the brain and an important intermediate in metabolism. In the present study, lactic acid bacteria (218) were isolated from six different fermented foods as potent sources of glutamic acid producers. The presumptive bacteria were tested for their ability to synthesize glutamic acid. Out of the 35 strains showing this capability, strain MNZ was determined as the highest glutamic-acid producer. Identification tests including 16S rRNA gene sequencing and sugar assimilation ability identified the strain MNZ as Lactobacillus plantarum. The characteristics of this microorganism related to its glutamic acid-producing ability, growth rate, glucose consumption and pH profile were studied. Results revealed that glutamic acid was formed inside the cell and excreted into the extracellular medium. Glutamic acid production was found to be growth-associated and glucose significantly enhanced glutamic acid production (1.032 mmol/L) compared to other carbon sources. A concentration of 0.7% ammonium nitrate as a nitrogen source effectively enhanced glutamic acid production. To the best of our knowledge this is the first report of glutamic acid production by lactic acid bacteria. The results of this study can be further applied for developing functional foods enriched in glutamic acid and subsequently ?-amino butyric acid (GABA) as a bioactive compound. PMID:22754309

  5. Survival of Listeria monocytogenes, Listeria innocua, and lactic acid bacteria in chill brines.

    PubMed

    Boyer, R R; Matak, K; Sumner, S S; Meadows, B; Williams, R C; Eifert, J D; Birbari, W

    2009-06-01

    Listeria monocytogenes is the pathogen of concern in ready-to-eat (RTE) meat products. Salt brines are used to chill processed meats. L. monocytogenes and lactic acid bacteria (LAB) can grow under saline conditions, and may compete with each other for nutrients. The objective of this study was to determine the effect of lactic acid bacteria (Enterococcus faecalis, Carnobacterium gallinarum, and Lactobacillus plantarum) on the survival of L. monocytogenes and Listeria innocua in brines stored under low temperatures for 10 d. Sterile tap water (STW) and 2 brine solutions (7.9% and 13.2% NaCl) were inoculated with 1 of 5 cocktails (L. monocytogenes, L. innocua, LAB, L. monocytogenes+ LAB, or L. innocua+ LAB) at initial concentrations of 7 log CFU/mL. Brines were stored for 10 d at 4 or 12 degrees C. Three replications of each brine concentration/cocktail/temperature combination were completed. No significant reductions of L. monocytogenes occurred in 7.9%[w/v] or 13.2%[w/v] brines when LAB were present; however, there were significant reductions after 10 d of L. monocytogenes in the STW solution when LAB were present (1.43 log CFU/mL at 4 degrees C and 3.02 log CFU/mL at 12 degrees C). L. innocua was significantly less resilient to environmental stresses of the brines than L. monocytogenes, both with and without LAB present (P< or = 0.05). These strains of lactic acid bacteria are not effective at reducing L. monocytogenes in brines at low temperatures. Furthermore, use of L. innocua as a model for L. monocytogenes is not appropriate under these environmental conditions. PMID:19646051

  6. Production of ?-Amino Butyric Acid in Tea Leaves wit Treatment of Lactic Acid Bacteria

    NASA Astrophysics Data System (ADS)

    Watanabe, Yuko; Hayakawa, Kiyoshi; Ueno, Hiroshi

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

  7. ?-Glucosidase activities of lactic acid bacteria: mechanisms, impact on fermented food and human health.

    PubMed

    Michlmayr, Herbert; Kneifel, Wolfgang

    2014-03-01

    Through the hydrolysis of plant metabolite glucoconjugates, ?-glucosidase activities of lactic acid bacteria (LAB) make a significant contribution to the dietary and sensory attributes of fermented food. Deglucosylation can release attractive flavour compounds from glucosylated precursors and increases the bioavailability of health-promoting plant metabolites as well as that of dietary toxins. This review brings the current literature on LAB ?-glucosidases into context by providing an overview of the nutritional implications of LAB ?-glucosidase activities. Based on biochemical and genomic information, the mechanisms that are currently considered to be critical for the hydrolysis of ?-glucosides by intestinal and food-fermenting LAB will also be reviewed. PMID:24330034

  8. [Antagonistic properties of lactic acid bacteria isolated from apparently healthy and osteoporotic women].

    PubMed

    Ohirchuk, K S; Poltavs'ka, O A; Kovalenko, N K

    2013-01-01

    Antagonistic activity of 74 cultures of lactic acid bacteria, isolated from healthy and osteoporotic women-patients aged 50-79 years, has been studied. It has been shown that the inhibitory effect of the strain studied was independent of the health of women (control group of women or patients with osteoporosis), but had strain specificity. Seventeen most active strains of lactobacilli, which showed the highest inhibitory activity against B. cereus, P. aeruginosa, P. vulgaris were selected. Only 6 strains of lactobacillus demonstrated specific antagonistic activity against the test-strains. PMID:23516836

  9. The passage of lactic acid bacteria from silage into rumen fluid, in vitro studies.

    PubMed

    Weinberg, Z G; Chen, Y; Gamburg, M

    2004-10-01

    Inoculated silages sometimes improve cattle performance, possibly because of probiotic effects of lactic acid bacteria (LAB) silage inoculants. The cause of improved animal performance following feeding with inoculated silage is unclear. One issue in studying this phenomenon is to find out whether LAB pass from silage into the rumen fluid and survive in it. The purpose of the present study was to determine whether LAB from inoculated and uninoculated silages pass into the rumen fluid in vitro. Wheat and corn silages, uninoculated or inoculated with 1 of 10 commercial silage inoculant LAB, were prepared in glass jars. After ensiling, a 2.5-g silage sample was added to 25 mL of heat-sterilized or strained rumen fluid together with 5 g/L glucose, and incubated for 48 h at 39 degrees C. Analysis of the incubated rumen fluid included pH measurement, enumeration of LAB, and determination of lactic acid and volatile fatty acids (VFA). The pH of the rumen fluid decreased during incubation; both heat-sterilized and strained rumen fluid contained large numbers of LAB. The heat-sterilized rumen fluid contained lactic acid in addition to VFA, whereas the strained rumen fluid contained only VFA. The results indicate that LAB pass from silage samples into the rumen fluid in vitro and survive there. Their interactions with rumen microorganisms should be studied further to understand how some silage inoculant LAB exhibit probiotic effects in dairy cattle. PMID:15377617

  10. Prevention of Aerobic Spoilage of Maize Silage by a Genetically Modified Killer Yeast, Kluyveromyces lactis, Defective in the Ability To Grow on Lactic Acid

    PubMed Central

    Kitamoto, H. K.; Hasebe, A.; Ohmomo, S.; Suto, E. G.; Muraki, M.; Iimura, Y.

    1999-01-01

    In this study, we propose a new process of adding a genetically modified killer yeast to improve the aerobic stability of silage. Previously constructed Kluyveromyces lactis killer strain PCK27, defective in growth on lactic acid due to disruption of the gene coding for phosphoenolpyruvate carboxykinase, a key enzyme for gluconeogenesis, inhibited the growth of Pichia anomala inoculated as an aerobic spoilage yeast and prevented a rise in pH in a model of silage fermentation. This suppressive effect of PCK27 was not only due to growth competition but also due to the killer protein produced. From these results, we concluded that strain PCK27 can be used as an additive to prolong the aerobic stability of maize silage. In the laboratory-scale experiment of maize silage, the addition of a killer yeast changed the yeast flora and significantly reduced aerobic spoilage. PMID:10508111

  11. Leucine incorporation by aerobic anoxygenic phototrophic bacteria in the Delaware estuary.

    PubMed

    Stegman, Monica R; Cottrell, Matthew T; Kirchman, David L

    2014-11-01

    Aerobic anoxygenic phototrophic (AAP) bacteria are well known to be abundant in estuaries, coastal regions and in the open ocean, but little is known about their activity in any aquatic ecosystem. To explore the activity of AAP bacteria in the Delaware estuary and coastal waters, single-cell (3)H-leucine incorporation by these bacteria was examined with a new approach that combines infrared epifluorescence microscopy and microautoradiography. The approach was used on samples from the Delaware coast from August through December and on transects through the Delaware estuary in August and November 2011. The percent of active AAP bacteria was up to twofold higher than the percentage of active cells in the rest of the bacterial community in the estuary. Likewise, the silver grain area around active AAP bacteria in microautoradiography preparations was larger than the area around cells in the rest of the bacterial community, indicating higher rates of leucine consumption by AAP bacteria. The cell size of AAP bacteria was 50% bigger than the size of other bacteria, about the same difference on average as measured for activity. The abundance of AAP bacteria was negatively correlated and their activity positively correlated with light availability in the water column, although light did not affect (3)H-leucine incorporation in light-dark experiments. Our results suggest that AAP bacteria are bigger and more active than other bacteria, and likely contribute more to organic carbon fluxes than indicated by their abundance. PMID:24824666

  12. Bacteria-mediated aerobic degradation of hexacosane in vitro conditions.

    PubMed

    Jauhari, Nitanshi; Mishra, Shweta; Kumari, Babita; Singh, S N

    2014-10-01

    In vitro degradation of hexacosane (C26H54), a HMW n-alkane, was studied in MSM by two bacterial strains i.e., Pseudomonas sp. BP10 and Stenotrophomonas nitritireducens E9, isolated from petroleum sludge, in isolation and combination. The results revealed that both the strains were able to metabolize hexacosane by 82% in isolation and 98% in their consortium after 7days. An enhancement of 16% in hexacosane degradation by the consortium indicated an additive action of bacterial strains. However, in control, a degradation of 21% was attributed to abiotic factors. During incubation with hexacosane, both the bacteria continued to multiply in isolation and consortium, which reflected that hexacosane was utilized by bacteria as a carbon and energy source. Activities of alkane hydroxylase and alcohol dehydrogenase were differentially expressed in isolation and combination, indicating their involvement in hexacosane degradation. Enhanced cell surface hydrophobicity and emulsification index and reduced surface tension also supported the degradation process. PMID:25125193

  13. Use of starter cultures of lactic acid bacteria and yeasts in the preparation of togwa, a Tanzanian fermented food.

    PubMed

    Mugula, J K; Narvhus, J A; Sørhaug, T

    2003-06-25

    Starter cultures of lactic acid bacteria (Lactobacillus brevis, Lactobacillus cellobiosus, Lactobacillus fermentum, Lactobacillus plantarum and Pediococcus pentosaceus) and yeasts (Candida pelliculosa, Candida tropicalis, Issatchenkia orientalis and Saccharomyes cerevisiae) isolated from native togwa were tested singly or in combination for their ability to ferment maize-sorghum gruel to produce togwa. All species of bacteria showed an ability to ferment the gruel as judged by lowering the pH from 5.87 to 3.24-3.49 and increasing the titratable acidity from 0.08% to 0.30-0.44% (w/w, lactic acid) in 24 h. Yeasts used singly showed little activity within 12 h, but lowered the pH to 3.57-4.81 and increased the acidity to 0.11-0.21% in 24 h. Yeasts in co-culture with lactic acid bacteria (LAB) had a modest effect on the final acidity (P<0.05). The number of lactic acid bacteria and yeasts increased while the Enterobacteriaceae decreased with fermentation time. The pH was lowered and lactic acid produced significantly (P<0.05) fastest in natural togwa fermentation and in samples fermented by L. plantarum or L. plantarum in co-culture with I. orientalis. The content of fermentable sugars was reduced during fermentation. Most volatile flavour compounds were produced in samples from fermentation by P. pentosaceus and I. orientalis in co-culture with either L. plantarum or L. brevis. PMID:12745235

  14. Novel bacteriocins from lactic acid bacteria (LAB): various structures and applications

    PubMed Central

    2014-01-01

    Bacteriocins are heat-stable ribosomally synthesized antimicrobial peptides produced by various bacteria, including food-grade lactic acid bacteria (LAB). These antimicrobial peptides have huge potential as both food preservatives, and as next-generation antibiotics targeting the multiple-drug resistant pathogens. The increasing number of reports of new bacteriocins with unique properties indicates that there is still a lot to learn about this family of peptide antibiotics. In this review, we highlight our system of fast tracking the discovery of novel bacteriocins, belonging to different classes, and isolated from various sources. This system employs molecular mass analysis of supernatant from the candidate strain, coupled with a statistical analysis of their antimicrobial spectra that can even discriminate novel variants of known bacteriocins. This review also discusses current updates regarding the structural characterization, mode of antimicrobial action, and biosynthetic mechanisms of various novel bacteriocins. Future perspectives and potential applications of these novel bacteriocins are also discussed. PMID:25186038

  15. The lactic acid bacteria metabolite phenyllactic acid inhibits both radial growth and sporulation of filamentous fungi

    PubMed Central

    2013-01-01

    Background Food spoilage caused by molds is a severe problem. In food and feed, e.g. dairy products, sourdough bread and silage, lactic acid bacteria are used as starter cultures. Besides lactic and acetic acid, some strains produce other low molecular weight compounds with antifungal activities. One of these metabolites is phenyllactic acid (PLA), well known for its antifungal effect. The inhibitory effect of PLA has only partially been investigated, and the objective of this study was to elucidate in detail the antifungal properties of PLA. Results We investigated the outgrowth of individual conidia from Aspergillus niger, Cladosporium cladosporioides and Penicillium roqueforti, and observed the morphologies of resulting colonies on solid media using different acid concentrations. We found that PLA inhibits molds similar to weak acid preservatives. Furthermore, it has an additional activity: at sub-inhibitory concentrations, fungal colonies displayed slower radial growth and inhibited sporulation. The L isoform of PLA is a more potent inhibitor than the D form. Increased expression of phiA was observed during PLA treatment. This gene was initially identified as being induced by Streptomyces-produced macrolide antibiotics, and is shown to be a structural protein in developed cells. This suggests that PhiA may act as a general stress protectant in fungi. Conclusion From a food protection perspective, the results of this study support the usage of lactic acid bacteria strains synthesizing PLA as starter cultures in food and feed. Such starter cultures could inhibit spore synthesis, which would be beneficial as many food borne fungi are spread by airborne spores. PMID:24229396

  16. Prediction of acid lactic-bacteria growth in turkey ham processed by high hydrostatic pressure

    PubMed Central

    Mathias, S.P.; Rosenthal, A.; Gaspar, A.; Aragão, G.M.F.; Slongo-Marcusi, A.

    2013-01-01

    High hydrostatic pressure (HHP) has been investigated and industrially applied to extend shelf life of meat-based products. Traditional ham packaged under microaerophilic conditions may sometimes present high lactic acid bacteria population during refrigerated storage, which limits shelf life due to development of unpleasant odor and greenish and sticky appearance. This study aimed at evaluating the shelf life of turkey ham pressurized at 400 MPa for 15 min and stored at 4, 8 and 12 °C, in comparison to the non pressurized product. The lactic acid bacteria population up to 107 CFU/g of product was set as the criteria to determine the limiting shelf life According to such parameter the pressurized sample achieved a commercial viability within 75 days when stored at 4 °C while the control lasted only 45 days. Predictive microbiology using Gompertz and Baranyi and Roberts models fitted well both for the pressurized and control samples. The results indicated that the high hydrostatic pressure treatment greatly increased the turkey ham commercial viability in comparison to the usual length, by slowing down the growth of microorganisms in the product. PMID:24159279

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

    PubMed Central

    Coda, Rossana; Pinto, Daniela; Gobbetti, Marco

    2012-01-01

    A pool of selected lactic acid bacteria was used for the sourdough fermentation of various cereal flours with the aim of synthesizing antioxidant peptides. The radical-scavenging activity of water/salt-soluble extracts (WSE) from sourdoughs was significantly (P < 0.05) higher than that of chemically acidified doughs. The highest activity was found for whole wheat, spelt, rye, and kamut sourdoughs. Almost the same results were found for the inhibition of linoleic acid autoxidation. WSE were subjected to reverse-phase fast protein liquid chromatography. Thirty-seven fractions were collected and assayed in vitro. The most active fractions were resistant to further hydrolysis by digestive enzymes. Twenty-five peptides of 8 to 57 amino acid residues were identified by nano-liquid chromatography-electrospray ionization-tandem mass spectrometry. Almost all of the sequences shared compositional features which are typical of antioxidant peptides. All of the purified fractions showed ex vivo antioxidant activity on mouse fibroblasts artificially subjected to oxidative stress. This study demonstrates the capacity of sourdough lactic acid bacteria to release peptides with antioxidant activity through the proteolysis of native cereal proteins. PMID:22156436

  18. Sourdough lactic acid bacteria: exploration of non-wheat cereal-based fermentation.

    PubMed

    Coda, Rossana; Cagno, Raffaella Di; Gobbetti, Marco; Rizzello, Carlo Giuseppe

    2014-02-01

    Cereal-based foods represent a very important source of biological as well as of cultural diversity, as testified by the wide range of derived fermented products. A trend that is increasingly attracting bakery industries as well as consumers is the use of non-conventional flours for the production of novel products, characterised by peculiar flavour and better nutritional value. Lactic acid bacteria microbiota of several non-wheat cereals and pseudo-cereals has been recently deeply investigated with the aim of studying the biodiversity and finding starter cultures for sourdough fermentation. Currently, the use of ancient or ethnic grains is mainly limited to traditional typical foods and the bread making process is not well standardised with consequent negative effects on the final properties. The challenge in fermenting such grains is represented by the necessity to combine good technology and sensory properties with nutritional/health benefits. The choice of the starter cultures has a critical impact on the final quality of cereal-based products, and strains that dominate and outcompete contaminants should be applied for specific sourdough fermentations. In this sense, screening and characterisation of the lactic acid bacteria microbiota is very useful in the improvement of a peculiar flour, from both a nutritional and technological point of view. PMID:24230473

  19. Oxalate-degrading capacities of lactic acid bacteria in canine feces.

    PubMed

    Ren, Zhihua; Pan, Cuiling; Jiang, Luyan; Wu, Cong; Liu, Yongwang; Zhong, Zhijun; Ran, Linwu; Ren, Fei; Chen, Xingxiang; Wang, Yangguang; Zhu, Yongxing; Huang, Kehe

    2011-09-28

    In this study, lactic acid bacteria in canine feces were isolated and identified, and their oxalate-degrading capacities were evaluated. The oxalate-degrading capacities were determined for 24 of 47 (51.06%) lactic acid bacteria isolates. Of these, 8 isolates [Leuconostoc mesenteroides (RL75), Lactococcus garvieae (CD2), Lactococcus subsp. lactis (CS21), Enterococcus faecium (CL71 and CL72), and Enterococcus faecalis (CD14, CS62, and CD12)] degraded more than 5% of the oxalate present, while the others degraded less than 5% of the oxalate in vitro. Isolates that degraded more than 5% of the oxalate present were selected for further examination. The oxalate-degrading capacities of individual isolates, a mixture of Enterococcus, a mixture of Lactococcus, and a mixture of the eight isolates were evaluated in media containing different concentrations of glucose (sufficient, insufficient, or no glucose). In comparison with the control medium, all of the individual isolates and mixtures of isolates could degrade oxalate in all three groups (P<0.05). In most cases, the isolates growing in medium with 20 g/L of glucose had higher oxalate-degrading capacities than those growing in medium with 2.5 g/L of glucose or no glucose. The mixture of all isolates showed higher oxalate-degrading capacity than the individual isolates and other mixtures. The oxalate-degrading capacities of the isolates were isolate dependent. PMID:21641129

  20. Technological and functional applications of low-calorie sweeteners from lactic acid bacteria.

    PubMed

    Patra, F; Tomar, S K; Arora, S

    2009-01-01

    Lactic acid bacteria (LAB) have been extensively used for centuries as starter cultures to carry out food fermentations and are looked upon as burgeoning "cell factories" for production of host of functional biomolecules and food ingredients. Low-calorie sugars have been a recent addition and have attracted a great deal of interest of researchers, manufacturers, and consumers for varied reasons. These sweeteners also getting popularized as low-carb sugars have been granted generally recommended as safe (GRAS) status by the U.S. Federal Drug Administration (USFDA) and include both sugars and sugar alcohols (polyols) which in addition to their technological attributes (sugar replacer, bulking agent, texturiser, humectant, cryoprotectant) have been observed to exert a number of health benefits (low calories, low glycemic index, anticariogenic, osmotic diuretics, obesity control, prebiotic). Some of these sweeteners successfully produced by lactic acid bacteria include mannitol, sorbitol, tagatose, and trehalose and there is a potential to further enhance their production with the help of metabolic engineering. These safe sweeteners can be exploited as vital food ingredients for development of low-calorie foods with added functional values especially for children, diabetic patients, and weight watchers. PMID:19200114

  1. Aerobic biodegradation of propylene glycol by soil bacteria.

    PubMed

    Toscano, Giuseppe; Cavalca, Lucia; Letizia Colarieti, M; Scelza, Rosalia; Scotti, Riccardo; Rao, Maria A; Andreoni, Vincenza; Ciccazzo, Sonia; Greco, Guido

    2013-09-01

    Propylene glycol (PG) is a main component of aircraft deicing fluids and its extensive use in Northern airports is a source of soil and groundwater contamination. Bacterial consortia able to grow on PG as sole carbon and energy source were selected from soil samples taken along the runways of Oslo Airport Gardermoen site (Norway). DGGE analysis of enrichment cultures showed that PG-degrading populations were mainly composed by Pseudomonas species, although Bacteroidetes were found, as well. Nineteen bacterial strains, able to grow on PG as sole carbon and energy source, were isolated and identified as different Pseudomonas species. Maximum specific growth rate of mixed cultures in the absence of nutrient limitation was 0.014 h(-1) at 4 °C. Substrate C:N:P molar ratios calculated on the basis of measured growth yields are in good agreement with the suggested values for biostimulation reported in literature. Therefore, the addition of nutrients is suggested as a suitable technique to sustain PG aerobic degradation at the maximum rate by autochthonous microorganisms of unsaturated soil profile. PMID:23187798

  2. [The phylogenetic diversity of aerobic organotrophic bacteria from the Dagan high-temperature oil field].

    PubMed

    Nazina, T N; Sokolova, D Sh; Shestakova, N M; Grigor'ian, A A; Mikha?lova, E M; Babich, T L; Lysenko, A M; Turova, T P; Poltaraus, A B; Feng, Tsin'syan; Ni, Fangtian; Beliaev, S S

    2005-01-01

    The distribution and species diversity of aerobic organotrophic bacteria in the Dagan high-temperature oil field (China), which is exploited via flooding, have been studied. Twenty-two strains of the most characteristic thermophilic and mesophilic aerobic organotrophic bacteria have been isolated from the oil stratum. It has been found that, in a laboratory, the mesophilic and thermophilic isolates grow in the temperature, pH, and salinity ranges characteristic of the injection well near-bottom zones or of the oil stratum, respectively, and assimilate a wide range of hydrocarbons, fatty acids, lower alcohols, and crude oil, thus exhibiting adaptation to the environment. Using comparative phylogenetic 16S rRNA analysis, the taxonomic affiliation of the isolates has been established. The aerobic microbial community includes gram-positive bacteria with a high and low G+C content of DNA, and gamma and beta subclasses of Proteobacteria. The thermophilic bacteria belong to the genera Geobacillus and Thermoactinomyces, and the mesophilic strains belong to the genera Bacillus, Micrococcus, Cellulomonas, Pseudomonas, and Acinetobacter. The microbial community of the oil stratum is dominated by known species of the genus Geobacillus (G. subterraneus, G. stearothermophilus, and G. thermoglucosidasius) and a novel species "Geobacillus jurassicus." A number of novel thermophilic oil-oxidizing bacilli have been isolated. PMID:16119855

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  4. Lactic acid bacteria and yeasts associated with spontaneous fermentations during the production of sour cassava starch in Brazil.

    PubMed

    Lacerda, Inayara C A; Miranda, Rose L; Borelli, Beatriz M; Nunes, Alvaro C; Nardi, Regina M D; Lachance, Marc-André; Rosa, Carlos A

    2005-11-25

    Sour cassava starch is a traditional fermented food used in the preparation of fried foods and baked goods such as traditional cheese breads in Brazil. Thirty samples of sour cassava starch were collected from two factories in the state of Minas Gerais. The samples were examined for the presence of lactic acid bacteria, yeasts, mesophilic microorganisms, Bacillus cereus and faecal coliforms. Lactic acid bacteria and yeasts isolates were identified by biochemical tests, and the identities were confirmed by molecular methods. Lactobacillus plantarum and Lactobacillus fermentum were the prevalent lactic acid bacteria in product from both factories, at numbers between 6.0 and 9.0 log cfu g(-)(1). Lactobacillus perolans and Lactobacillus brevis were minor fractions of the population. Galactomyces geothricum and Issatchenkia sp. were the prevalent yeasts at numbers of 5.0 log cfu g(-)(1). A species similar to Candida ethanolica was frequently isolated from one factory. Mesophilic bacteria and amylolytic microorganisms were recovered in high numbers at all stages of the fermentation. B. cereus was found at low numbers in product at both factories. The spontaneous fermentations associated with the production of sour cassava starch involve a few species of lactic acid bacteria at high numbers and a variety of yeasts at relatively low numbers. PMID:16153731

  5. Aerobic Anoxygenic Phototrophic Bacteria in the Mid-Atlantic Bight and the North Pacific Gyre. Revised

    NASA Technical Reports Server (NTRS)

    Cottrell, Matthew T.; Mannino, Antonio; Kirchman, David L.

    2005-01-01

    The abundance of aerobic anoxygenic phototrophic (AM) bacteria, cyanobacteria and heterotrophs was examined in the Mid-Atlantic Bight and the central North Pacific gyre using infrared fluorescence microscopy coupled with image analysis and flow cytometry. AAP bacteria comprised 5% to 16% of total prokaryotes in the Atlantic but only 5% or less in the Pacific. In the Atlantic, AAP bacterial abundance was as much as 2-fold higher than Prochlorococcus and 10-folder higher than Synechococcus. In contrast, Prochlorococcus outnumbered AAP bacteria 5- to 50-fold in the Pacific. In both oceans, subsurface abundance maxima occurred within the photic zone, and AAP bacteria were least abundant below the 1% light depth. Concentrations of bacteriochlorophyll a (BChl a) were low (approx.1%) compared to chlorophyll a. Although the BChl a content of AAP bacteria per cell was typically 20- to 250-fold lower than the divinyl-chlorophyll a content of Prochlorococcus, in shelf break water the pigment content of AAP bacteria approached that of Prochlorococcus. The abundance of AAP bacteria rivaled some groups of strictly heterotrophic bacteria and was often higher than the abundance of known AAP genera (Erythrobacter and Roseobacter spp.). The distribution of AAP bacteria in the water column, which was similar in the Atlantic and the Pacific, was consistent with phototrophy.

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

    PubMed Central

    Zoumpopoulou, Georgia; Pepelassi, Eudoxie; Papaioannou, William; Georgalaki, Marina; Maragkoudakis, Petros A.; Tarantilis, Petros A.; Polissiou, Moschos; Tsakalidou, Effie; Papadimitriou, Konstantinos

    2013-01-01

    In the present study we investigated the incidence of bacteriocins produced by 236 lactic acid bacteria (LAB) food isolates against pathogenic or opportunistic pathogenic oral bacteria. This set of LAB contained several strains (?17%) producing bacteriocins active against food-related bacteria. Interestingly only Streptococcus macedonicus ACA-DC 198 was able to inhibit the growth of Streptococcus oralis, Streptococcus sanguinis and Streptococcus gordonii, while Lactobacillus fermentum ACA-DC 179 and Lactobacillus plantarun ACA-DC 269 produced bacteriocins solely against Streptococcus oralis. Thus, the percentage of strains that were found to produce bacteriocins against oral bacteria was ~1.3%. The rarity of bacteriocins active against oral LAB pathogens produced by food-related LAB was unexpected given their close phylogenetic relationship. Nevertheless, when tested in inhibition assays, the potency of the bacteriocin(s) of S. macedonicus ACA-DC 198 against the three oral streptococci was high. Fourier-transform infrared spectroscopy combined with principal component analysis revealed that exposure of the target cells to the antimicrobial compounds caused major alterations of key cellular constituents. Our findings indicate that bacteriocins produced by food-related LAB against oral LAB may be rare, but deserve further investigation since, when discovered, they can be effective antimicrobials. PMID:23443163

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

    PubMed Central

    2012-01-01

    Lactic acid bacteria (LAB) have taken centre stage in perspectives of modern fermented food industry and probiotic based therapeutics. These bacteria encounter various stress conditions during industrial processing or in the gastrointestinal environment. Such conditions are overcome by complex molecular assemblies capable of synthesizing and/or metabolizing molecules that play a specific role in stress adaptation. Thiols are important class of molecules which contribute towards stress management in cell. Glutathione, a low molecular weight thiol antioxidant distributed widely in eukaryotes and Gram negative organisms, is present sporadically in Gram positive bacteria. However, new insights on its occurrence and role in the latter group are coming to light. Some LAB and closely related Gram positive organisms are proposed to possess glutathione synthesis and/or utilization machinery. Also, supplementation of glutathione in food grade LAB is gaining attention for its role in stress protection and as a nutrient and sulfur source. Owing to the immense benefits of glutathione, its release by probiotic bacteria could also find important applications in health improvement. This review presents our current understanding about the status of glutathione and its role as an exogenously added molecule in food grade LAB and closely related organisms. PMID:22920585

  8. Zebrafish gut colonization by mCherry-labelled lactic acid bacteria.

    PubMed

    Russo, Pasquale; Iturria, Iñaki; Mohedano, Maria Luz; Caggianiello, Graziano; Rainieri, Sandra; Fiocco, Daniela; Angel Pardo, Miguel; López, Paloma; Spano, Giuseppe

    2015-04-01

    A critical feature of probiotic microorganisms is their ability to colonize the intestine of the host. Although the microbial potential to adhere to the human gut lumen has been investigated in in vitro models, there is still much to discover about their in vivo behaviour. Zebrafish is a vertebrate model that is being widely used to investigate various biological processes shared with humans. In this work, we report on the use of the zebrafish model to investigate the in vivo colonization ability of previously characterized probiotic lactic acid bacteria. Lactobacillus plantarum Lp90, L. plantarum B2 and Lactobacillus fermentum PBCC11.5 were fluorescently tagged by transfer of the pRCR12 plasmid, which encodes the mCherry protein and which was constructed in this work. The recombinant bacteria were used to infect germ-free zebrafish larvae. After removal of bacteria, the colonization ability of the strains was monitored until 3 days post-infection by using a fluorescence stereomicroscope. The results indicated differential adhesion capabilities among the strains. Interestingly, a displacement of bacteria from the medium to the posterior intestinal tract was observed as a function of time that suggested a transient colonization by probiotics. Based on fluorescence observation, L. plantarum strains exhibited a more robust adhesion capability. In conclusion, the use of pRCR12 plasmid for labelling Lactobacillus strains provides a powerful and very efficient tool to monitor the in vivo colonization in zebrafish larvae and to investigate the adhesion ability of probiotic microorganisms. PMID:25586576

  9. Production of l -lactic acid from a mixture of xylose and glucose by co-cultivation of lactic acid bacteria

    Microsoft Academic Search

    M. Taniguchi; T. Tokunaga; K. Horiuchi; K. Hoshino; K. Sakai; T. Tanaka

    2004-01-01

    The production of optically pure lactic acid in a high yield from xylose or a mixture of xylose and glucose, which is a model hydrolysate of lignocellulose, is described. In a single cultivation, Enterococcus casseliflavus produced 38 g\\/l of lactic acid with an optical purity of 96% enantiomeric excess (ee) and 6.4 g\\/l of acetic acid from 50 g\\/l of xylose when MRS

  10. Genome Analysis of Food Grade Lactic Acid-Producing Bacteria: From Basics to Applications

    PubMed Central

    Mayo, B; van Sinderen, D; Ventura, M

    2008-01-01

    Whole-genome sequencing has revolutionized and accelerated scientific research that aims to study the genetics, biochemistry and molecular biology of bacteria. Lactic acid-producing bacteria, which include lactic acid bacteria (LAB) and bifidobacteria, are typically Gram-positive, catalase-negative organisms, which occupy a wide range of natural plant- and animal-associated environments. LAB species are frequently involved in the transformation of perishable raw materials into more stable, pleasant, palatable and safe fermented food products. LAB and bifidobacteria are also found among the resident microbiota of the gastrointestinal and/or genitourinary tracts of vertebrates, where they are believed to exert health-promoting effects. At present, the genomes of more than 20 LAB and bifidobacterial species have been completely sequenced. Their genome content reflects its specific metabolism, physiology, biosynthetic capabilities, and adaptability to varying conditions and environments. The typical LAB/bifidobacterial genome is relatively small (from 1.7 to 3.3 Mb) and thus harbors a limited assortment of genes (from around 1,600 to over 3,000). These small genomes code for a broad array of transporters for efficient carbon and nitrogen assimilation from the nutritionally-rich niches they usually inhabit, and specify a rather limited range of biosynthetic and degrading capabilities. The variation in the number of genes suggests that the genome evolution of each of these bacterial groups involved the processes of extensive gene loss from their particular ancestor, diversification of certain common biological activities through gene duplication, and acquisition of key functions via horizontal gene transfer. The availability of genome sequences is expected to revolutionize the exploitation of the metabolic potential of LAB and bifidobacteria, improving their use in bioprocessing and their utilization in biotechnological and health-related applications. PMID:19440514

  11. Anaerobic lactic acid degradation during ensilage of whole crop maize inoculated with lactobacillus buchneri inhibits yeast growth and improves aerobic stability

    PubMed

    Driehuis; Elferink; Spoelstra

    1999-10-01

    Aerobic deterioration of silages is initiated by (facultative) aerobic micro-organisms, usually yeasts, that oxidize the preserving organic acids. In this study, a Lactobacillus buchneri strain isolated from maize silage was evaluated for its potential as a bacterial inoculant that enhances aerobic stability of silages. In four experiments, chopped whole crop maize (30-43% dry matter (DM)) was inoculated with Lact. buchneri and ensiled in laboratory silos. Uninoculated silages served as controls. Analysis of silages treated with Lact. buchneri at levels of 103-106 cfu g-1 after about 3 months of anaerobic storage showedthat acetic acid and 1-propanol contents increased with inoculum levels above 104 cfu g-1,whereas lactic acid decreased. Propionic acid, silage pH and DM loss increased withinoculum levels above 105 cfu g-1. Time course experiments with maize inoculated with Lact. buchneri at 4 x 104-2 x 105 cfu g-1 showed that up to 7-14 d after ensiling, Lact. buchneri had no effect on silage characteristics. Thereafter, the lactic acid content of the inoculated silages declined and, simultaneously, acetic acid and, to a lesser extent, propionic acid and 1-propanol, accumulated. Inoculation reduced survival of yeasts during the anaerobic storage phase and inhibited yeast growth when the silage was exposed to O2, resulting in a substantial improvement in aerobic stability. The results indicate that the use of Lact. buchneri as a silage inoculant can enhance aerobic stability by inhibition of yeasts. The ability of the organism to ferment lactic acid to acetic acid appears to be an important underlying principle of this effect. PMID:10583687

  12. First isolation of thermophilic aerobic non-sporulating heterotrophic bacteria from deep-sea hydrothermal vents

    Microsoft Academic Search

    ViggóThór Marteinsson; Jean-Louis Birrien; Jakob K. Kristjánsson; Daniel Prieur

    1995-01-01

    Thermophilic aerobic non-sporulating heterotrophic bacteria were isolated for the first time from deep-sea hydrothermal vents. Samples were taken at Snakepit (Mid-Atlantic Ridge) and Guaymas Basin (Gulf of California). Isolates consisting of pleomorphic rods, single cells or pairs, formed filaments of variable length, and grew at 70°C or some up to 80°C. They were halotolerant and unable to grow anaerobically, except

  13. Can pulsed xenon ultraviolet light systems disinfect aerobic bacteria in the absence of manual disinfection?

    PubMed

    Jinadatha, Chetan; Villamaria, Frank C; Ganachari-Mallappa, Nagaraja; Brown, Donna S; Liao, I-Chia; Stock, Eileen M; Copeland, Laurel A; Zeber, John E

    2015-04-01

    Whereas pulsed xenon-based ultraviolet light no-touch disinfection systems are being increasingly used for room disinfection after patient discharge with manual cleaning, their effectiveness in the absence of manual disinfection has not been previously evaluated. Our study indicates that pulsed xenon-based ultraviolet light systems effectively reduce aerobic bacteria in the absence of manual disinfection. These data are important for hospitals planning to adopt this technology as adjunct to routine manual disinfection. PMID:25681301

  14. Aerobic bacteria occurring in the hind-gut of the cockroach, Blatta orientalis

    PubMed Central

    Burgess, N. R. H.; McDermott, S. N.; Whiting, J.

    1973-01-01

    Methods are described for the isolation and identification of aerobic bacteria occurring naturally in the hind-gut of the cockroach Blatta orientalis captured from a number of wild sources, to establish whether or not human pathogens occurred naturally within the gut. During the investigation an organism was frequently found which could not be classified in any described species, and for which we propose the name Escherichia blattae. PMID:4571611

  15. Aerobic bacteria occurring in the hind-gut of the cockroach, Blatta orientalis.

    PubMed

    Burgess, N R; McDermott, S N; Whiting, J

    1973-03-01

    Methods are described for the isolation and identification of aerobic bacteria occurring naturally in the hind-gut of the cockroach Blatta orientalis captured from a number of wild sources, to establish whether or not human pathogens occurred naturally within the gut. During the investigation an organism was frequently found which could not be classified in any described species, and for which we propose the name Escherichia blattae. PMID:4571611

  16. Antimicrobial activity of an Amazon medicinal plant (Chancapiedra) (Phyllanthus niruri L.) against Helicobacter pylori and lactic acid bacteria.

    PubMed

    Ranilla, Lena Gálvez; Apostolidis, Emmanouil; Shetty, Kalidas

    2012-06-01

    The potential of water extracts of the Amazon medicinal plant Chancapiedra (Phyllanthus niruri L.) from Ecuador and Peru for antimicrobial activity against Helicobacter pylori and different strains of lactic acid bacteria such as Lactobacillus acidophilus, Lactobacillus casei and Lactobacillus plantarum was investigated. H. pylori was inhibited by both water extracts in a dose dependent manner, whereas lactic acid bacterial growth was not affected. Both extracts contained ellagic acid and hydroxycinnamic acid derivatives and exhibited high free radical scavenging linked-antioxidant activities (89%). However, gallic acid was detected only in the Ecuadorian extract. Preliminary studies on the mode of action of Chancapiedra against H. pylori revealed that inhibition may not involve proline dehydrogenase-based oxidative phosphorylation inhibition associated with simple mono-phenolics and could involve ellagitannins or other non-phenolic compounds through a yet unknown mechanism. This study provides evidence about the potential of Chancapiedra for H. pylori inhibition without affecting beneficial lactic acid bacteria. PMID:22034238

  17. Isolating and evaluating lactic acid bacteria strains for effectiveness of Leymus chinensis silage fermentation.

    PubMed

    Zhang, Q; Li, X J; Zhao, M M; Yu, Z

    2014-10-01

    Five LAB strains were evaluated using the acid production ability test, morphological observation, Gram staining, physiological, biochemical and acid tolerance tests. All five strains (LP1, LP2, LP3, LC1 and LC2) grew at pH 4·0, and LP1 grew at 15°C. Strains LP1, LP2 and LP3 were identified as Lactobacillus plantarum, whereas LC1 and LC2 were classified as Lactobacillus casei by sequencing 16S rDNA. The five isolated strains and two commercial inoculants (PS and CL) were added to native grass and Leymus chinensis (Trin.) Tzvel. for ensiling. All five isolated strains decreased the pH and ammonia nitrogen content, increased the lactic acid content and LP1, LP2 and LP3 increased the acetic content and lactic/acetic acid ratio of L. chinensis silage significantly. The five isolated strains and two commercial inoculants decreased the butyric acid content of the native grass silage. LP2 treatment had lower butyric acid content and ammonia nitrogen content than the other treatments. The five isolated strains improved the quality of L. chinensis silage. The five isolated strains and the two commercial inoculants were not effective in improving the fermentation quality of the native grass silage, but LP2 performed better comparatively. Significance and impact of the study: Leymus chinensis is an important grass in China and Russia, being the primary grass of the short grassland 'steppe' regions of central Asia. However, it has been difficult to make high-quality silage of this species because of low concentration of water-soluble carbohydrates (WSC). Isolating and evaluating lactic acid bacteria strains will be helpful for improving the silage quality of this extensively grown species. PMID:24888497

  18. Characterization, Identification and Application of Lactic Acid Bacteria Isolated from Forage Paddy Rice Silage

    PubMed Central

    Ni, Kuikui; Wang, Yanping; Li, Dongxia; Cai, Yimin; Pang, Huili

    2015-01-01

    There has been growing interest to develop forage rice as a new feed resource for livestock. This study was to characterize the natural population of lactic acid bacteria (LAB) and select potentially excellent strains for paddy rice silage preparation in China. One hundred and twenty-six strains were isolated and screened from paddy rice silage prepared using a small-scale fermentation system, and ninety-nine of these isolates were considered to be LAB based on their Gram-positive and catalase-negative morphology and the production of most of their metabolic products as lactic acid. These isolates were divided into eight groups (A-H) on the basis of their morphological and biochemical characteristics. The Group A to H strains were identified as Lactobacillus (L.) plantarum subsp. plantarum (species ratio: 8.1%), L. casei (5.1%), Leuconostoc (Ln.) pseudomesenteroides (11.1%), Pediococcus (P.) pentosaceus (24.2%), Enterococcus (E.) mundtii (12.1%), Lactococcus (Lc.) garvieae (15.2%), E. faecium (9.1%) and Lc. lactis subsp. lactis (15.2%) based on sequence analyses of their 16S rRNA and recA genes. P. pentosaceus was the most abundant member of the LAB population in the paddy rice silage. A selected strain, namely L. casei R 465, was found to be able to grow under low pH conditions and to improve the silage quality with low pH and a relatively high content of lactic acid. This study demonstrated that forage paddy rice silage contains abundant LAB species and its silage can be well preserved by inoculation with LAB, and that strain R 465 can be a potentially excellent inoculant for paddy rice silage. PMID:25803578

  19. Characterization, identification and application of lactic Acid bacteria isolated from forage paddy rice silage.

    PubMed

    Ni, Kuikui; Wang, Yanping; Li, Dongxia; Cai, Yimin; Pang, Huili

    2015-01-01

    There has been growing interest to develop forage rice as a new feed resource for livestock. This study was to characterize the natural population of lactic acid bacteria (LAB) and select potentially excellent strains for paddy rice silage preparation in China. One hundred and twenty-six strains were isolated and screened from paddy rice silage prepared using a small-scale fermentation system, and ninety-nine of these isolates were considered to be LAB based on their Gram-positive and catalase-negative morphology and the production of most of their metabolic products as lactic acid. These isolates were divided into eight groups (A-H) on the basis of their morphological and biochemical characteristics. The Group A to H strains were identified as Lactobacillus (L.) plantarum subsp. plantarum (species ratio: 8.1%), L. casei (5.1%), Leuconostoc (Ln.) pseudomesenteroides (11.1%), Pediococcus (P.) pentosaceus (24.2%), Enterococcus (E.) mundtii (12.1%), Lactococcus (Lc.) garvieae (15.2%), E. faecium (9.1%) and Lc. lactis subsp. lactis (15.2%) based on sequence analyses of their 16S rRNA and recA genes. P. pentosaceus was the most abundant member of the LAB population in the paddy rice silage. A selected strain, namely L. casei R 465, was found to be able to grow under low pH conditions and to improve the silage quality with low pH and a relatively high content of lactic acid. This study demonstrated that forage paddy rice silage contains abundant LAB species and its silage can be well preserved by inoculation with LAB, and that strain R 465 can be a potentially excellent inoculant for paddy rice silage. PMID:25803578

  20. Biodegradation of nonlignocellulosic substances I: system for complete decomposition of garbage using sawdust and aerobic soil bacteria

    Microsoft Academic Search

    Minoru Terazawa; Sakae Horisawa; Yutaka Tamai; Kenzo Yamashita

    1999-01-01

    A system for effective garbage decomposition using sawdust and aerobic soil bacteria was examined. The machinery used in this\\u000a process, the garbage automatic decomposer-extinguisher (GADS), is composed of a container with an automatic mechanical mixer\\u000a and a drain for liquid formed by the decomposition of garbage. The aerobic soil bacteria, cultivated in sawdust, degrades\\u000a garbage within the container. The GADE

  1. High Abundances of Aerobic Anoxygenic Photosynthetic Bacteria in the South Pacific Ocean?

    PubMed Central

    Lami, Raphaël; Cottrell, Matthew T.; Ras, Joséphine; Ulloa, Osvaldo; Obernosterer, Ingrid; Claustre, Hervé; Kirchman, David L.; Lebaron, Philippe

    2007-01-01

    Little is known about the abundance, distribution, and ecology of aerobic anoxygenic phototrophic (AAP) bacteria, particularly in oligotrophic environments, which represent 60% of the ocean. We investigated the abundance of AAP bacteria across the South Pacific Ocean, including the center of the gyre, the most oligotrophic water body of the world ocean. AAP bacteria, Prochlorococcus, and total prokaryotic abundances, as well as bacteriochlorophyll a (BChl a) and divinyl-chlorophyll a concentrations, were measured at several depths in the photic zone along a gradient of oligotrophic conditions. The abundances of AAP bacteria and Prochlorococcus were high, together accounting for up to 58% of the total prokaryotic community. The abundance of AAP bacteria alone was up to 1.94 × 105 cells ml?1 and as high as 24% of the overall community. These measurements were consistent with the high BChl a concentrations (up to 3.32 × 10?3 ?g liter?1) found at all stations. However, the BChl a content per AAP bacterial cell was low, suggesting that AAP bacteria are mostly heterotrophic organisms. Interestingly, the biovolume and therefore biomass of AAP bacteria was on average twofold higher than that of other prokaryotic cells. This study demonstrates that AAP bacteria can be abundant in various oligotrophic conditions, including the most oligotrophic regime of the world ocean, and can account for a large part of the bacterioplanktonic carbon stock. PMID:17496136

  2. Horizontal gene transfer amongst probiotic lactic acid bacteria and other intestinal microbiota: what are the possibilities? A review

    Microsoft Academic Search

    Carol A. van Reenen; Leon M. T. Dicks

    2011-01-01

    Probiotics are live cultures, usually lactic acid bacteria, which are ingested to promote a healthy gastrointestinal tract.\\u000a These organisms require certain traits to survive and compete in this niche, but these traits may be transferred to other\\u000a microbiota in the gastrointestinal tract (GIT). Similarly, virulence factors from pathogens may be acquired by probiotic strains.\\u000a Bacteria have developed a plethora of

  3. The Biodiversity of Lactic Acid Bacteria in Greek Traditional Wheat Sourdoughs Is Reflected in Both Composition and Metabolite Formation

    Microsoft Academic Search

    Luc De Vuyst; Vincent Schrijvers; Spiros Paramithiotis; Bart Hoste; Marc Vancanneyt; Jean Swings; George Kalantzopoulos; Effie Tsakalidou; Winy Messens

    2002-01-01

    Lactic acid bacteria (LAB) were isolated from Greek traditional wheat sourdoughs manufactured without the addition of baker's yeast. Application of sodium dodecyl sulfate-polyacrylamide gel electrophoresis of total cell protein, randomly amplified polymorphic DNA-PCR, DNA-DNA hybridization, and 16S ribosomal DNA sequence analysis, in combination with physiological traits such as fructose fermentation and mannitol production, allowed us to classify the isolated bacteria

  4. Succession of dominant and antagonistic lactic acid bacteria in fermented cucumber: Insights from a PCR-based approach

    Microsoft Academic Search

    Atul Kumar Singh; Aiyagari Ramesh

    2008-01-01

    The goal of the investigation was to study the succession of major groups of lactic acid bacteria (LAB) and their antagonism in salt-fermented cucumber using PCR. In a direct detection method as well as a short enrichment process, PCR enabled detection of Leuconostoc and Lactobacillus during early hours of fermentation. Subsequently, Lactobacillus and Pediococcus emerged as the dominant genera. Nucleic

  5. Prevalence and impact of single-strain starter cultures of lactic acid bacteria on metabolite formation in sourdough

    Microsoft Academic Search

    Frédéric Ravyts; Luc De Vuyst

    2011-01-01

    Flavour of type II sourdoughs is influenced by the ingredients, processing conditions, and starter culture composition. It is, however, not fully clear to what extent different sourdough lactic acid bacteria (LAB) contribute to flavour. Therefore, two types of flour (rye and wheat) and different LAB starter culture strains were used to prepare sourdoughs, thereby leaving the yeast microbiota uncontrolled. All

  6. Utilization of Echium amoenum Extract as a Growth Medium for the Production of Organic Acids by Selected Lactic Acid Bacteria

    Microsoft Academic Search

    Forough Jahandideh; Seyed Mohammad Mousavi; Seyed Hadi Razavi

    Gol-gavzaban (Echium amoenum Fisch. & Mey.) is an indigenous herbal plant, related to the Boraginaceae family, cultivated historically in Iran. In this study, the suitability of Echium extract as a raw material for production of fermented juice by four strains of lactic acid bacteria (Lactobacillus paracasei, Lactobacillus acidophilus, Lactobacillus plantarum, and Lactobacillus delbrueckii) was examined. Echium extract was inoculated with

  7. Use of Hydrolysates from Yellowfin Tuna ( Thunnus albacares ) Heads as a Complex Nitrogen Source for Lactic Acid Bacteria

    Microsoft Academic Search

    Reza Safari; Ali Motamedzadegan; Mahmoudreza Ovissipour; Joe Mack Regenstein; Asbjorn Gildberg; Barbara Rasco

    Two different peptones obtained by enzymatic hydrolysis of yellowfin tuna (Thunnus albacares) head waste have been shown to be effective in promoting the growth of lactic acid bacteria (Lactobacillus bulgaricus Persian Type Culture Collection (PTCC) 1332, Lactobacillus acidophilus PTCC 1643, Lactobacillus casei PTCC 1608, Lactobacillus delbrukii PTCC 1333, Lactobacillus plantarum PTCC 1058, Lactococcus lactis PTCC 1336, and Lactobacillus sakei PTCC

  8. Lactic Acid Bacteria Isolated from Indigenous Fermented Bamboo Products of Arunachal Pradesh in India and Their Functionality

    Microsoft Academic Search

    Buddhiman Tamang; Jyoti P. Tamang

    2009-01-01

    Ekung, eup and hirring are some common indigenous fermented bamboo products of Northeast India. We have isolated, characterized, and identified the predominant lactic acid bacteria (LAB) from 44 samples of ekung, eup, and hirring and studied their technological properties. The phenotypic characterizations of LAB isolates were based on physiological, biochemical tests and API kits, and were identified as Lactobacillus plantarum,

  9. The isolation of lactic acid bacteria from human colonic biopsies after enrichment on lactose derivatives and rye arabinoxylo-oligosaccharides

    Microsoft Academic Search

    P Kontula; M.-L Suihko; T Suortti; M Tenkanen; T Mattila-Sandholm; A von Wright

    2000-01-01

    Lactic acid bacteria (LAB) were isolated from human colon biopsies on LAMVAB by enrichment with different substrates such as lactose derivatives, rye arabinoxylo-oligosaccharides and rye fractions. The selected isolates were tested for their ability to adhere to Caco-2 cells. Only Lactobacillus species were enriched under these conditions. From 161 isolates screened, 28% were identified by ribotyping as Lactobacillus rhamnosus, 29%

  10. A lytic enzyme cocktail from Streptomyces sp. B578 for the control of lactic and acetic acid bacteria in wine

    Microsoft Academic Search

    V. Blättel; K. Wirth; H. Claus; B. Schlott; P. Pfeiffer; H. König

    2009-01-01

    Beside yeasts, lactic acid bacteria (LAB) are the most abundant microbes in must during vinification. Whereas Oenococcos oeni is commercially used as a starter culture for the biological acid reduction in wines, other species are responsible for different\\u000a types of wine spoilage. Members of the genera Pediococcus, Weissella, Leuconostoc, and Lactobacillus are producers of exopolysaccharide slimes, biogenic amines, acetic acid,

  11. Phenotypic and genotypic characterization of lactic acid bacteria isolated from cow, ewe and goat dairy artisanal farmhouses

    PubMed Central

    Reginensi, Stella M.; González, Marcela J.; Bermúdez, Jorge

    2013-01-01

    Lactic acid bacteria collected from artisanal farmhouses were characterized using a polyphasic approach. Phenotypic methods including biochemical assays, ribosomal DNA restriction analysis and 16S rDNA sequence analysis were performed. This approach provides accuracy for identification, and helps to avoid the loss of natural biodiversity including potentially valuable strains. PMID:24294232

  12. Screening of lactic acid bacteria for reducing power using a tetrazolium salt reduction method on milk agar.

    PubMed

    Michelon, Damien; Tachon, Sybille; Ebel, Bruno; De Coninck, Joëlle; Feron, Gilles; Gervais, Patrick; Yvon, Mireille; Cachon, Rémy

    2013-02-01

    Reducing activity is a physiological property of lactic acid bacteria (LAB) of technological importance. We developed a solid medium with tetrazolium dyes enabling weakly and strongly reducing LAB to be discriminated. It was used to quantify populations in a mixed culture (spreading method) and screen strains (spot method). PMID:23063698

  13. Screening, selection and characterization of phytic acid degrading lactic acid bacteria from chicken intestine.

    PubMed

    Raghavendra, Ponnala; Halami, Prakash M

    2009-07-31

    This study was undertaken to screen and select potent phytate degrading lactic acid bacteria and to evaluate their additional characteristic features. Forty lactic acid bacterial strains were isolated from different sources and screened for their ability to degrade myo-inositol hexaphosphate or IP(6) by cobalt chloride staining (plate assay) method, using calcium or sodium salt of phytic acid as substrate. All the forty isolates were able to degrade calcium phytate. However, only two Pediococcus pentosaceus strains (CFR R38 and CFR R35) were found to degrade sodium phytate. These strains showed phytase activity of 213 and 89 U at 50 degrees C, respectively and poor acid phosphatase activity. These strains were further evaluated for additional characteristic features. At pH 2, P. pentosaceus strains CFR R38 and CFR R35 showed 50.7 and 48.5 percentage survivability after 2 h of incubation respectively and they could also withstand 0.3% ox-bile. These cultures exhibited 54.6 and 44.8% of hydrophobicity to xylene, antibacterial activity against food borne pathogens and possessed beta-galactosidase activity. The resistance pattern to several antibiotics was also analyzed. The present study indicates that these strains, having phytate degrading ability and other characteristic features can be exploited as starter cultures in fermented foods to improve the mineral bioavailability. PMID:19481282

  14. Improvement of the fermentative activity of lactic acid bacteria starter culture by the addition of Mn²?.

    PubMed

    Cheng, Xin; Dong, Ying; Su, Ping; Xiao, Xiang

    2014-11-01

    Production of lactic acid bacteria (LAB) starter with raw material has received much scientific investigation, but little information is available on the influences of some trace elements on the growth and fermentative activity of LAB. Based on this fact, this paper aimed to investigate the effects of Mn(2+) on the performance of Lactobacillus plantarum CX-15 starter with Jerusalem artichoke (JA) as the main medium substrate. The results showed that Mn(2+) addition had a significant beneficial affect on the fermentative activity of L. plantarum CX-15 starter. In contrast, the lack of Mn(2+) would cause the subsequent fermentation significantly slower, whether the cell density in starter culture was higher or lower. The possible mechanism of these phenomenons was further elucidated by the time course analysis of the specific activities of metabolism key enzymes during the culture processes of L. plantarum CX-15 starter. Compared to the fermentation processes without Mn(2+) addition, it was found that Mn(2+) addition would enhance the lactate dehydrogenase (LDH) activity but reduce the activities of pyruvate dehydrogenase (PDH) and ATPase activity. Therefore, it could be concluded that the improvement of L. plantarum starter fermentative activity was probably a consequence of Mn(2+) acting as "metabolic switch," which regulated the metabolic flux from pyruvic acid to lactic acid and other metabolism pathway. PMID:25146195

  15. Emerging roles of lactic acid bacteria in protection against colorectal cancer

    PubMed Central

    Zhong, Li; Zhang, Xufei; Covasa, Mihai

    2014-01-01

    Colorectal cancer (CRC) is the third leading cause of cancer deaths worldwide and the fourth most common cancer diagnosed among men and women in the United States. Considering the risk factors of CRC, dietary therapy has become one of the most effective approaches in reducing CRC morbidity and mortality. The use of probiotics is increasing in popularity for both the prevention and treatment of a variety of diseases. As the most common types of microbes used as probiotics, lactic acid bacteria (LAB) are comprised of an ecologically diverse group of microorganisms united by formation of lactic acid as the primary metabolite of sugar metabolism. LAB have been successfully used in managing diarrhea, food allergies, and inflammatory bowel disease. LAB also demonstrated a host of properties in preventing colorectal cancer development by inhibiting initiation or progression through multiple pathways. In this review, we discuss recent insights into cellular and molecular mechanisms of LAB in CRC prevention including apoptosis, antioxidant DNA damages, immune responses, and epigenetics. The emerging experimental findings from clinical trials as well as the proposed mechanisms of gut microbiota in carcinogenesis will also be briefly discussed. PMID:24976724

  16. Halotolerance and survival kinetics of lactic acid bacteria isolated from jalapeño pepper (Capsicum annuum L.) fermentation.

    PubMed

    González-Quijano, Génesis Karendash; Dorantes-Alvarez, Lidia; Hernández-Sánchez, Humberto; Jaramillo-Flores, María Eugenia; de Jesús Perea-Flores, María; Vera-Ponce de León, Arturo; Hernández-Rodríguez, César

    2014-08-01

    The microbiota associated with spontaneous fermentation of vegetables in a saline substrate may represent an important group of bacteria in the food industry. In this work, the lactic acid bacteria (LAB) Weissella cibaria, Lactobacillus plantarum, Lactobacillus paraplantarum, and Leuconostoc citreum were identified by partial 16S rRNA gene sequence analysis. In addition, entophytic bacteria such as Pantoea eucalypti, Pantoea anthophila, Enterobacter cowanii, and Enterobacter asburiae were detected, but they were irrelevant for the fermentation process and were inhibited after 12 h of fermentation when the pH decreased from 6.5 to 4.9. Moreover, 2 species of yeast were isolated and identified as Hanseniaspora pseudoguilliermondii and Kodamaea ohmeri by their partial 26S rRNA gene sequence. The growth of LAB was evaluated at different sodium chloride contents. L. citreum was the most halotolerant species followed by L. plantarum and W. cibaria with a concentration index to obtain a 50% population reduction (IC(50)) of 7.2%, 6.6%, and 5.2%, respectively. Furthermore, the growth of LAB and Escherichia coli O157:H7 was evaluated in the presence of the main phenylpropanoids from chilli peppers such as p-coumaric and ferulic acid. It was determined that LAB can grow in both acids at 4 mM, unlike E. coli O157:H7, whose growth is inhibited in the presence of these acids. PMID:25039289

  17. [Antioxidant properties of lactic acid bacteria--probiotic and yogurt strains].

    PubMed

    Uskova, M A; Kravchenko, L V

    2009-01-01

    Antioxidant properties of 14 strains of lactic acid bacteria were evaluated in vitro using FRAP assay, inhibition of luminol oxidation in Hb-H2O2 system and inhibition of NADPH-Fe2+ induced microsomal lipid peroxidation. All strains demonstrated high reducing properties, but only L. casei spp. (including L. casei 114001) and L. fermentum ME-3 revealed pronounced ability to suppress oxidation of luminol (by 43-65,8%) and microsomal lipid peroxidation (by 57,9-89,5%). Either L. casei 114001 (10(8) CFU suspended in physiological solution) or fermented dairy drink containing equivalent amount of L. casei 114001 were daily administered orally to male Wistar rats. Antioxidant capacity of blood plasma, liver and intestines of animals elevated while MDA content in blood plasma decreased. PMID:19514338

  18. Anti-obesity effects of gut microbiota are associated with lactic acid bacteria.

    PubMed

    Tsai, Yueh-Ting; Cheng, Po-Ching; Pan, Tzu-Ming

    2014-01-01

    The prevalence of obesity is rapidly becoming endemic in industrialized countries and continues to increase in developing countries worldwide. Obesity predisposes people to an increased risk of developing metabolic syndrome. Recent studies have described an association between obesity and certain gut microbiota, suggesting that gut microbiota might play a critical role in the development of obesity. Although probiotics have many beneficial health effects in humans and animals, attention has only recently been drawn to manipulating the gut microbiota, such as lactic acid bacteria (LAB), to influence the development of obesity. In this review, we first describe the causes of obesity, including the genetic and environmental factors. We then describe the relationship between the gut microbiota and obesity, and the mechanisms by which the gut microbiota influence energy metabolism and inflammation in obesity. Lastly, we focus on the potential role of LAB in mediating the effects of the gut microbiota in the development of obesity. PMID:24232731

  19. Growth inhibition of lactic acid bacteria in ham by nisin: a model approach.

    PubMed

    Kalschne, Daneysa L; Geitenes, Simone; Veit, Marilei R; Sarmento, Cleonice M P; Colla, Eliane

    2014-12-01

    Lactic acid bacteria (LAB) have been described as spoilage organisms in vacuum-packed cooked ham. A Fractional Factorial Design was performed to investigate the relative merits of sodium chloride, sodium lactate, sodium tripolyphosphate, sodium erythorbate, nisin and pediocin, in limiting the Lactobacillus sakei growth in broth culture. This allowed rejection of sodium chloride, sodium lactate and sodium erythorbate (no significant effects on growth), and a Central Composite Rotatable Design broth culture study was performed comparing the effects of nisin and pediocin. From this study, nisin was identified as a more important variable for inclusion into a cooked ham model (significant effects on growth parameters: logarithmic increase in the population, exponential microbial growth rate and lag phase extension). The validation of this outcome in a model formulation of vacuum-packed sliced cooked ham (0.001%, 0.007% and 0.013% of nisin) stored for 60days, confirmed the inhibitory effect of nisin on total LAB growth. PMID:25108514

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

    PubMed

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

    2010-10-01

    The effect of different fermenting microorganisms on growth of a mycotoxin- producing Aspergillus nomius was assayed. Two lactic acid bacteria, Lactobacillus fermentum and Lactobacillus rhamnosus, and Saccharomyces cerevisiae, all of which are widely used in fermentation and preservation of food, were assayed on their fungus inhibitory properties. Assays were carried out by simultaneous inoculation of one of the possible inhibiting microorganisms and the fungus or subsequent inoculation of one of the microorganisms followed by the fungus. All three microorganisms assayed showed growth inhibition of the mycotoxin-producing Aspergillus strain. L. rhamnosus O236, isolated from sheep milk and selected for its technological properties, showed highest fungal inhibition of the microorganisms assayed. The use of antifungal LAB with excellent technological properties rather than chemical preservatives would enable the food industry to produce organic food without addition of chemical substances. PMID:24031582

  1. Medical and Personal Care Applications of Bacteriocins Produced by Lactic Acid Bacteria

    NASA Astrophysics Data System (ADS)

    Dicks, L. M. T.; Heunis, T. D. J.; van Staden, D. A.; Brand, A.; Noll, K. Sutyak; Chikindas, M. L.

    The frequent use of antibiotics has led to a crisis in the antibiotic ­resistance of pathogens associated with humans and animals. Antibiotic resistance and the emergence of multiresistant bacterial pathogens have led to the investigation of alternative antimicrobial agents to treat and prevent infections in both humans and animals. Research on antimicrobial peptides, with a special interest on bacteriocins of lactic acid bacteria, is entering a new era with novel applications other than food preservation. Many scientists are now focusing on the application of these peptides in medicinal and personal care products. However, it is difficult to assess the success of such ventures due to the dearth of information that has been published and the lack of clinical trials.

  2. The depletion of sodium nitrite by lactic acid bacteria isolated from kimchi.

    PubMed

    Oh, Chang-Kyung; Oh, Myung-Chul; Kim, Soo-Hyun

    2004-01-01

    Nitrites, whether added or naturally occurring in foods, are potential carcinogens, and controlling their concentrations is important for maintaining a safe food supply. In this study we investigated the depletion of sodium nitrite (150 microg/mL) during the fermentation in Lactobacilli MRS broth at 5, 10, 15, 20, 25, 30, and 36 degrees C by lactic acid bacteria (LAB-A, -B, -C, and -D) isolated from kimchi and Leuconostoc mesenteroides strain KCTC3100. The four species of lactic acid bacteria isolated from kimchi were identified as L. mesenteroides, and all produced depletion of less than 20% of sodium nitrite after 10 days of incubation at 5 degrees C. There was less than 40% depletion after 9 days at 10 degrees C, 86.4-92.8% after 7 days at 15 degrees C, 81.4-87.8% after 4 days and more than 90.0% after 5 days at 20 degrees C, 76.3-85.7% after 3 days and more than 90.0% after 5 days at 25 degrees C, and more than 90.0% after 2 days at 30 and 36 degrees C. The depletion by LAB isolates was similar or higher than that by L. mesenteroides strain KCTC3100, and in particular, the LAB-D strain showed the highest depletion effect of all the strains tested, up to 15 degrees C. From these results, the strains isolated from kimchi were very effective for the depletion of sodium nitrite at high temperature, and all sodium nitrite was depleted at the initial period of incubation (1-2 days) at 30 and 36 degrees C. But as the temperature was lowered, the depletion effect of sodium nitrite was decreased in all the strains tested from kimchi. This illustrates that the depletion of nitrite by each strain is subject to the influence of temperatures. PMID:15117551

  3. Binding of heterocyclic amines by lactic acid bacteria from miso, a fermented Japanese food.

    PubMed

    Rajendran, R; Ohta, Y

    1998-02-01

    Miso, a widely used Japanese fermented food was analysed for its lactic acid bacterial count on bromocresol purple agar. The binding of eight different foodborne carcinogenic heterocyclic amines to 25 bacterial isolates from miso were investigated. The heterocyclic amines used were 3-amino-1,4-dimethyl[5H]pyrido(4,3-b)indole (Trp-P-1), 3-amino-1-methyl[5H]pyrido(4,3-b)indole (Trp-P-2), 2-amino-6-methyldipyrido(1,2-a:3'2'-d)imidazole (Glu-P-1), 2-amino-1-methyl-6-phenylimidazo(4,5-b)pyridine (PhIP), 2-amino-dimethylimidazo(4,5f)quinoline (IQ), 2-amino-3,4-dimethylimidazo(4,5-f) quinoline (MeIQ), 2-amino-3,8-dimethylimidazo(4,5-f)quinoxaline (MeIQx), and 2-amino-3-methyl-9H-pyrido(2,3)indole (MeA alpha C). The lyophilized cells of all of the isolates exhibited high binding activity towards Trp-P-1, Trp-P-2, MeA alpha C, and PhIP, while Glu-P-1 and IQ were not effectively bound. Of the isolates tested, the strongest and weakest binders were identified as Pediococcus acidilactici 1 and 2, respectively. Lyophilized cell wall fractions, heat-treated cells, and the cytoplasmic contents of P. acidilactici 1 and 2 were analysed for their ability to bind to different mutagens. Pure cell wall and peptidoglycan showed greater binding activity than the bacterial cells. Cytoplasmic content also showed some binding, but it was much less effective. The impact of enzymes (amylase, protease, cellulase, chitinase, muraminase, and peptidase) and acetylation of Trp-P-1 and IQ on the binding action of bacteria and cell wall material were also analysed to understand the possible processes involved in the binding of lactic acid bacteria to carcinogenic heterocyclic amines. PMID:9543712

  4. High nitrogen removal from wastewater with several new aerobic bacteria isolated from diverse ecosystems.

    PubMed

    Ping, Li; De-Li, Li; Nahimana, Liberat; Chen, Shu-Li; Yang, Xi; Zhao, Li

    2006-01-01

    Three new bacteria HS-03, HS-043 and HS-047 isolated from different ecosystems were found capable of aerobic denitrification. The potential application of these strains in wastewater treatment under aerobic conditions was investigated. These three bacteria all presented high nitrogen removal from wastewater that more than 98% of 10 mmol/L nitrate could be removed in 12-24 h by adding cheap external carbon source and low concentration of iron as well as molybdate. The mechanism at molecular level was analyzed. The success of this aerobic denitrification applied to wastewater treatment may serve as an alternative to enhance the practical nitrogen removal from wastewater. Main biochemical and physiological features of these strains were characterized. The 16S rDNA sequences were compared with the published data in GenBank by using BLAST. The results of phenotype and genotype proved that strain HS-03 and HS-047 belonged to Pseudomonas stutzeri and Pseudomonas pseudoalcaligenes respectively. Strain HS-043 was identified as Delftia acidovorans of which denitrifying activity has not previously been explored. PMID:17294651

  5. Influence of sodium chloride, pH, and lactic acid bacteria on anaerobic lactic acid utilization during fermented cucumber spoilage

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cucumbers are preserved commercially by natural fermentations in 5% to 8% sodium chloride (NaCl) brines. Occasionally, fermented cucumbers spoil after the primary fermentation is complete. This spoilage has been characterized by decreases in lactic acid and a rise in brine pH caused by microbial ins...

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

    PubMed

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

    2015-07-01

    A stochastic model was developed for simultaneous growth of low numbers of Listeria monocytogenes and populations of lactic acid bacteria from the aroma producing cultures applied in cottage cheese. During more than two years, different batches of cottage cheese with aroma culture were analysed for pH, lactic acid concentration and initial concentration of lactic acid bacteria. These data and bootstrap sampling were used to represent product variability in the stochastic model. Lag time data were estimated from observed growth data (lactic acid bacteria) and from literature on L. monocytogenes single cells. These lag time data were expressed as relative lag times and included in growth models. A stochastic model was developed from an existing deterministic growth model including the effect of five environmental factors and inter-bacterial interaction [Østergaard, N.B, Eklöw, A and Dalgaard, P. 2014. Modelling the effect of lactic acid bacteria from starter- and aroma culture on growth of Listeria monocytogenes in cottage cheese. International Journal of Food Microbiology. 188, 15-25]. Growth of L. monocytogenes single cells, using lag time distributions corresponding to three different stress levels, was simulated. The simulated growth was subsequently compared to growth of low concentrations (0.4-1.0CFU/g) of L. monocytogenes in cottage cheese, exposed to similar stresses, and in general a good agreement was observed. In addition, growth simulations were performed using population relative lag time distributions for L. monocytogenes as reported in literature. Comparably good predictions were obtained as for the simulations performed using lag time data for individual cells of L. monocytogenes. Therefore, when lag time data for individual cells are not available, it was suggested that relative lag time distributions for L. monocytogenes can be used as a qualified default assumption when simulating growth of low concentrations of L. monocytogenes. PMID:25847186

  7. Numbers, diversity, and morphological characteristics of aerobic, chemoheterotrophic bacteria in deep subsurface sediments from a site in South Carolina

    Microsoft Academic Search

    David L. Balkwill

    1989-01-01

    The aerobic, chemoheterotrophic bacteria indigenous to deep aquifers and other subsurface sediments (depths to 265 m) at a site in South Carolina were characterized by direct microscopy, enumeration of viable cells, analysis of colony morphologies on plates, and analysis of cell morphologies of isolated strains. Substantial numbers of viable bacteria (1010\\/g) were present in all transmissive, aquifer sediments, and their

  8. The combined efficacy of carvacrol and modified atmosphere packaging on the survival of Salmonella, Campylobacter jejuni and lactic acid bacteria on Turkey breast cutlets.

    PubMed

    Nair, Divek V T; Kiess, Aaron; Nannapaneni, Rama; Schilling, Wes; Sharma, Chander Shekhar

    2015-08-01

    The primary objective of this study was to determine the efficacy of carvacrol in combination with modified atmosphere packaging (MAP) in reducing Salmonella on turkey breast cutlets stored at 4 °C. In experiment I, carvacrol (0.5, 1, and 2% v/v) was applied as surface treatment and samples were stored under aerobic condition or as surface and dip treatments followed by storage in an environment of 100% carbon dioxide. The findings of the experiment I revealed the synergistic activity of carvacrol with carbon dioxide in reducing Salmonella when used as dip treatment compared to the surface treatment. In experiment II, turkey breast cutlets were dip treated with carvacrol (0.25, 0.5, and 1% v/v) for 30 s and stored under MAP (95% carbon dioxide and 5% oxygen) to evaluate the efficacy against Salmonella, Campylobacter jejuni and lactic acid bacteria on turkey breast cutlets. In experiment II, the combined application of carvacrol and MAP resulted in 1.0-2.0 log CFU/g reduction (P ? 0.05) of both Salmonella and Campylobacter on turkey breast cutlets for 7 d storage at 4 °C. MAP alone and in combination with carvacrol reduced lactic acid bacteria (P ? 0.05) on cutlets stored at 4 °C for 21 d period. There was no difference (P ? 0.05) in meat color among treatments and controls except for an increased paleness of meat (P ? 0.05) observed for the 1% carvacrol treated cutlets stored under MAP after 21 d of storage. The high concentration of carbon dioxide and carvacrol treatments did not cause any alteration in meat pH (P ? 0.05). In conclusion, carvacrol was effective at a low concentration of 0.25% (v/v) in reducing Salmonella and C. jejuni by ?1.0 log CFU/g when stored under MAP. PMID:25846923

  9. GH1-family 6-P-?-glucosidases from human microbiome lactic acid bacteria

    PubMed Central

    Michalska, Karolina; Tan, Kemin; Li, Hui; Hatzos-Skintges, Catherine; Bearden, Jessica; Babnigg, Gyorgy; Joachimiak, Andrzej

    2013-01-01

    In lactic acid bacteria and other bacteria, carbohydrate uptake is mostly governed by phosphoenolpyruvate-dependent phosphotransferase systems (PTSs). PTS-dependent translocation through the cell membrane is coupled with phosphorylation of the incoming sugar. After translocation through the bacterial membrane, the ?-glycosidic bond in 6?-­P-­?-glucoside is cleaved, releasing 6-P-?-glucose and the respective aglycon. This reaction is catalyzed by 6-P-?-glucosidases, which belong to two glycoside hydrolase (GH) families: GH1 and GH4. Here, the high-resolution crystal structures of GH1 6-P-?-glucosidases from Lactobacillus plantarum (LpPbg1) and Streptococcus mutans (SmBgl) and their complexes with ligands are reported. Both enzymes show hydrolytic activity towards 6?-P-?-glucosides. The LpPbg1 structure has been determined in an apo form as well as in a complex with phosphate and a glucose molecule corresponding to the aglycon molecule. The S. mutans homolog contains a sulfate ion in the phosphate-dedicated subcavity. SmBgl was also crystallized in the presence of the reaction product 6-P-?-glucose. For a mutated variant of the S. mutans enzyme (E375Q), the structure of a 6?-P-salicin complex has also been determined. The presence of natural ligands enabled the definition of the structural elements that are responsible for substrate recognition during catalysis. PMID:23519420

  10. Sugar-coated: exopolysaccharide producing lactic acid bacteria for food and human health applications.

    PubMed

    Ryan, P M; Ross, R P; Fitzgerald, G F; Caplice, N M; Stanton, C

    2015-03-11

    The human enteric microbiome represents a veritable organ relied upon by the host for a range of metabolic and homeostatic functions. Through the production of metabolites such as short chain fatty acids (SCFA), folate, vitamins B and K, lactic acid, bacteriocins, peroxides and exopolysaccharides, the bacteria of the gut microbiome provide nutritional components for colonocytes, liver and muscle cells, competitively exclude potential pathogenic organisms and modulate the hosts immune system. Due to the extensive variation in structure, size and composition, microbial exopolysaccharides represent a useful set of versatile natural ingredients for the food industrial sector, both in terms of their rheological properties and in many cases, their associated health benefits. The exopolysaccharide-producing bacteria that fall within the 35 Lactobacillus and five Bifidobacterium species which have achieved qualified presumption of safety (QPS) and generally recognised as safe (GRAS) status are of particular interest, as their inclusion in food products can avoid considerable scrutiny. In addition, additives commonly utilised by the food industry are becoming unattractive to the consumer, due to the demand for a more 'natural' and 'clean labelled' diet. In situ production of exopolysaccharides by food-grade cultures in many cases confers similar rheological and sensory properties in fermented dairy products, as traditional additives, such as hydrocolloids, collagen and alginate. This review will focus on microbial synthesis of exopolysaccharides, the human health benefits of dietary exopolysaccharides and the technofunctional applications of exopolysaccharide-synthesising microbes in the food industry. PMID:25580594

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

    PubMed

    Gaspar, Paula; Carvalho, Ana L; Vinga, Susana; Santos, Helena; Neves, Ana Rute

    2013-11-01

    The lactic acid bacteria (LAB) are a functionally related group of low-GC Gram-positive bacteria known essentially for their roles in bioprocessing of foods and animal feeds. Due to extensive industrial use and enormous economical value, LAB have been intensively studied and a large body of comprehensive data on their metabolism and genetics was generated throughout the years. This knowledge has been instrumental in the implementation of successful applications in the food industry, such as the selection of robust starter cultures with desired phenotypic traits. The advent of genomics, functional genomics and high-throughput experimentation combined with powerful computational tools currently allows for a systems level understanding of these food industry workhorses. The technological developments in the last decade have provided the foundation for the use of LAB in applications beyond the classic food fermentations. Here we discuss recent metabolic engineering strategies to improve particular cellular traits of LAB and to design LAB cell factories for the bioproduction of added value chemicals. PMID:23567148

  12. Evaluation of culture media for selective enumeration of bifidobacteria and lactic acid bacteria

    PubMed Central

    Süle, Judit; Kõrösi, Tímea; Hucker, Attila; Varga, László

    2014-01-01

    The purpose of this study was to test the suitability of Transgalactosylated oligosaccharides-mupirocin lithium salt (TOS-MUP) and MRS-clindamycin-ciprofloxacin (MRS-CC) agars, along with several other culture media, for selectively enumerating bifidobacteria and lactic acid bacteria (LAB) species commonly used to make fermented milks. Pure culture suspensions of a total of 13 dairy bacteria strains, belonging to eight species and five genera, were tested for growth capability under various incubation conditions. TOS-MUP agar was successfully used for the selective enumeration of both Bifidobacterium animalis subsp. lactis BB-12 and B. breve M-16 V. MRS-CC agar showed relatively good selectivity for Lactobacillus acidophilus, however, it also promoted the growth of Lb. casei strains. For this reason, MRS-CC agar can only be used as a selective medium for the enumeration of Lb. acidophilus if Lb. casei is not present in a product at levels similar to or exceeding those of Lb. acidophilus. Unlike bifidobacteria and coccus-shaped LAB, all the lactobacilli strains involved in this work were found to grow well in MRS pH 5.4 agar incubated under anaerobiosis at 37 °C for 72 h. Therefore, this method proved to be particularly suitable for the selective enumeration of Lactobacillus spp. PMID:25477939

  13. Antimicrobial Peptides Targeting Gram-negative Pathogens, Produced and Delivered by Lactic Acid Bacteria

    PubMed Central

    Volzing, Katherine; Borrero, Juan; Sadowsky, Michael J.; Kaznessis, Yiannis N.

    2014-01-01

    We present results of tests with recombinant Lactococcus lactis that produce and secrete heterologous antimicrobial peptides with activity against Gram-negative pathogenic Escherichia coli and Salmonella. In an initial screening, the activities of numerous candidate antimicrobial peptides, made by solid state synthesis, were assessed against several indicator pathogenic E. coli and Salmonella strains. Peptides A3APO and Alyteserin were selected as top performers based on high antimicrobial activity against the pathogens tested and on significantly lower antimicrobial activity against L. lactis. Expression cassettes containing the signal peptide of the protein Usp45 fused to the codon optimized sequence of mature A3APO and Alyteserin were cloned under the control of a nisin-inducible promoter nisA and transformed into L. lactis IL1403. The resulting recombinant strains were induced to express and secrete both peptides. A3APO- and Alyteserin-containing supernatants from these recombinant L. lactis inhibited the growth of pathogenic E. coli and Salmonella by up to 20-fold, while maintaining the host’s viability. This system may serve as a model for the production and delivery of antimicrobial peptides by lactic acid bacteria to target Gram-negative pathogenic bacteria populations. PMID:23808914

  14. Antimicrobial peptides targeting Gram-negative pathogens, produced and delivered by lactic acid bacteria.

    PubMed

    Volzing, Katherine; Borrero, Juan; Sadowsky, Michael J; Kaznessis, Yiannis N

    2013-11-15

    We present results of tests with recombinant Lactococcus lactis that produce and secrete heterologous antimicrobial peptides with activity against Gram-negative pathogenic Escherichia coli and Salmonella . In an initial screening, the activities of numerous candidate antimicrobial peptides, made by solid state synthesis, were assessed against several indicator pathogenic E. coli and Salmonella strains. Peptides A3APO and Alyteserin were selected as top performers based on high antimicrobial activity against the pathogens tested and on significantly lower antimicrobial activity against L. lactis . Expression cassettes containing the signal peptide of the protein Usp45 fused to the codon-optimized sequence of mature A3APO and Alyteserin were cloned under the control of a nisin-inducible promoter PnisA and transformed into L. lactis IL1403. The resulting recombinant strains were induced to express and secrete both peptides. A3APO- and Alyteserin-containing supernatants from these recombinant L. lactis inhibited the growth of pathogenic E. coli and Salmonella by up to 20-fold, while maintaining the host's viability. This system may serve as a model for the production and delivery of antimicrobial peptides by lactic acid bacteria to target Gram-negative pathogenic bacteria populations. PMID:23808914

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

    PubMed Central

    Call, Emma K.; Klaenhammer, Todd R.

    2013-01-01

    Lactic acid bacteria (LAB) are a diverse group of Gram-positive bacteria found in a vast array of environments including dairy products and the human gastrointestinal tract (GIT). In both niches, surface proteins play a crucial role in mediating interactions with the surrounding environment. The sortase enzyme is responsible for covalently coupling a subset of sortase-dependent proteins (SDPs) to the cell wall of Gram-positive organisms through recognition of a conserved C-terminal LPXTG motif. Genomic sequencing of LAB and annotation has allowed for the identification of sortase and SDPs. Historically, sortase and SDPs were predominately investigated for their role in mediating pathogenesis. Identification of these proteins in LAB has shed light on their important roles in mediating nutrient acquisition through proteinase P as well as positive probiotic attributes including adhesion, mucus barrier function, and immune signaling. Furthermore, sortase expression signals in LAB have been exploited as a means to develop oral vaccines targeted to the GIT. In this review, we examine the collection of studies which evaluate sortase and SDPs in select species of dairy-associated and health promoting LAB. PMID:23579319

  16. Lactic acid bacteria-20 years exploring their potential as live vectors for mucosal vaccination.

    PubMed

    Wyszy?ska, Agnieszka; Kobierecka, Patrycja; Bardowski, Jacek; Jagusztyn-Krynicka, El?bieta Katarzyna

    2015-04-01

    Lactic acid bacteria (LAB) are a diverse group of Gram-positive, nonsporulating, low G?+?C content bacteria. Many of them have been given generally regarded as safe status. Over the past two decades, intensive genetic and molecular research carried out on LAB, mainly Lactococcus lactis and some species of the Lactobacillus genus, has revealed new, potential biomedical LAB applications, including the use of LAB as adjuvants, immunostimulators, or therapeutic drug delivery systems, or as factories to produce therapeutic molecules. LAB enable immunization via the mucosal route, which increases effectiveness against pathogens that use the mucosa as the major route of entry into the human body. In this review, we concentrate on the encouraging application of Lactococcus and Lactobacillus genera for the development of live mucosal vaccines. First, we present the progress that has recently been made in the field of developing tools for LAB genetic manipulations, which has resulted in the successful expression of many bacterial, parasitic, and viral antigens in LAB strains. Next, we discuss the factors influencing the efficacy of the constructed vaccine prototypes that have been tested in various animal models. Apart from the research focused on an application of live LABs as carriers of foreign antigens, a lot of work has been recently done on the potential usage of nonliving, nonrecombinant L. lactis designated as Gram-positive enhancer matrix (GEM), as a delivery system for mucosal vaccination. The advantages and disadvantages of both strategies are also presented. PMID:25750046

  17. Fast identification of wine related lactic acid bacteria by multiplex PCR.

    PubMed

    Petri, A; Pfannebecker, J; Fröhlich, J; König, H

    2013-02-01

    The microflora of must and wine consists of yeasts, acetic acid bacteria and lactic acid bacteria (LAB). The latter group plays an important role for wine quality. The malolactic fermentation carried out by LAB leads to deacidification and stabilisation of wines. Nevertheless, LAB are often associated with wine spoilage. They are mainly responsible for the formation of biogenic amines. Furthermore, some strains produce exopolysaccharide slimes, acetic acid, diacetyl and other off-flavours. In this context a better monitoring of the vinification process is crucial to improve wine quality. Moreover, a lot of biodiversity studies would also profit from a fast and reliable identification method. In this study, we propose a species-specific multiplex PCR system for a rapid and simultaneous detection of 13 LAB species, frequently occurring in must or wine: Lactobacillus brevis, Lb. buchneri, Lb. curvatus, Lb. hilgardii, Lb. plantarum, Leuconostoc mesenteroides, Oenococcus oeni, Pediococcus acidilactici, P. damnosus, P. inopinatus, P. parvulus, P. pentosaceus and Weissella paramesenteroides. PMID:23122500

  18. Control of Listeria monocytogenes in fresh cheese using protective lactic acid bacteria.

    PubMed

    Coelho, M C; Silva, C C G; Ribeiro, S C; Dapkevicius, M L N E; Rosa, H J D

    2014-11-17

    In the past years, there has been a particular focus on the application of bacteriocins produced by lactic acid bacteria (LAB) in controlling the growth of pathogenic bacteria in foods. The aim of this study was to select LAB strains with antimicrobial activity, previously isolated from a traditional Azorean artisanal cheese (Pico cheese), in order to identify those with the greatest potential in reducing Listeria monocytogenes in fresh cheese. Eight bacteriocin producer strains identified as Lactococcus lactis (1) and Enterococcus faecalis (7) were tested. In general, the bacteriocin-producing strains presented a moderate growth in fresh cheese at refrigeration temperatures (4 °C), increasing one log count in three days. They exhibited slow acidification capacity, despite the increased production of lactic acid displayed by some strains after 24h. Bacteriocin activity was only detected in the whey of fresh cheese inoculated with two Enterococcus strains, but all cheeses made with bacteriocin-producing strains inhibited L. monocytogenes growth in the agar diffusion bioassay. No significant differences were found in overall sensory evaluation made by a non-trained panel of 50-52 tasters using the isolates as adjunct culture in fresh cheese, with the exception of one Enterococcus strain. To test the effect of in situ bacteriocin production against L. monocytogenes, fresh cheese was made from pasteurized cows' milk inoculated with bacteriocin-producing LAB and artificially contaminated with approximately 10(6) CFU/mL of L. monocytogenes. The numbers of L. monocytogenes were monitored during storage of fresh cheese at refrigeration temperature (4 °C) for up to 15 days. All strains controlled the growth of L. monocytogenes, although some Enterococcus were more effective in reducing the pathogen counts. After 7 days, this reduction was of approximately 4 log units compared to the positive control. In comparison, an increase of 4 log CFU/mL in pathogen numbers was detected over the same period, in the absence of bacteriocin-producing LAB. The combination of two bacteriocin producing Enterococcus sp. optimized the reduction of L. monocytogenes counts in fresh cheese, reducing by approximately 5 log units after 7 days. The present work demonstrates that using bacteriocin-producing strains in the manufacture of fresh cheese might contribute to preventing the growth of undesirable pathogenic bacteria such as L. monocytogenes. A blend of two strains demonstrated great potential as a protective culture for the cheese making process. PMID:25222327

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

    PubMed

    Argyri, Anthoula A; Zoumpopoulou, Georgia; Karatzas, Kimon-Andreas G; Tsakalidou, Effie; Nychas, George-John E; Panagou, Efstathios Z; Tassou, Chrysoula C

    2013-04-01

    The present study aims to evaluate the probiotic potential of lactic acid bacteria (LAB) isolated from naturally fermented olives and select candidates to be used as probiotic starters for the improvement of the traditional fermentation process and the production of newly added value functional foods. Seventy one (71) lactic acid bacterial strains (17 Leuconostoc mesenteroides, 1 Ln. pseudomesenteroides, 13 Lactobacillus plantarum, 37 Lb. pentosus, 1 Lb. paraplantarum, and 2 Lb. paracasei subsp. paracasei) isolated from table olives were screened for their probiotic potential. Lb. rhamnosus GG and Lb. casei Shirota were used as reference strains. The in vitro tests included survival in simulated gastrointestinal tract conditions, antimicrobial activity (against Listeria monocytogenes, Salmonella Enteritidis, Escherichia coli O157:H7), Caco-2 surface adhesion, resistance to 9 antibiotics and haemolytic activity. Three (3) Lb. pentosus, 4 Lb. plantarum and 2 Lb. paracasei subsp. paracasei strains demonstrated the highest final population (>8 log cfu/ml) after 3 h of exposure at low pH. The majority of the tested strains were resistant to bile salts even after 4 h of exposure, while 5 Lb. plantarum and 7 Lb. pentosus strains exhibited partial bile salt hydrolase activity. None of the strains inhibited the growth of the pathogens tested. Variable efficiency to adhere to Caco-2 cells was observed. This was the same regarding strains' susceptibility towards different antibiotics. None of the strains exhibited ?-haemolytic activity. As a whole, 4 strains of Lb. pentosus, 3 strains of Lb. plantarum and 2 strains of Lb. paracasei subsp. paracasei were found to possess desirable in vitro probiotic properties similar to or even better than the reference probiotic strains Lb. casei Shirota and Lb. rhamnosus GG. These strains are good candidates for further investigation both with in vivo studies to elucidate their potential health benefits and in olive fermentation processes to assess their technological performance as novel probiotic starters. PMID:23200662

  20. Phenotypic and genotypic characterization of lactic Acid bacteria from traditional cheese in khorramabad city of iran with probiotic potential.

    PubMed

    Ghahremani, Enayat; Mardani, Mahnaz; Rezapour, Sadegh

    2015-03-01

    Lactic acid bacteria (LAB) with proteolitic activity are used as aromatic and antibacterial substances, cholesterol reduces, bile salt hydrolyses, and probiotic. The aims of this project were to isolate and identify natural LAB flora involved in traditional fermentation in cheeses of Khoramabad city and also to survey their probiotic potential. In order to achieve this goal, LAB were isolated and characterized using phenotypic and genotypic methods (PCR-sequencing); in the next stage, they were analyzed lowering cholesterol medium, hydrolysis of the bile, resistance to bile-resistant PH acidic stomach. At the end of the study, 88 cocci and 3 bacill were found: 58 Enterococcus faecium, 16 Enterococcus hirae, 5 Lactococcus lactis, 3 Lactobacillus plantarum, and 9 undetermined. The probiotic results of the bacteria had effects on the reduction of cholesterol, resistance to stomach acid, had relative antibacterial effects, and some strains had effects on hydrolyzing the bile. For further identification, the PCR method and the application of 16s-DNA-ITS genes and its sequencing were found useful. This study showed that lactic acid bacteria in the traditional cheese of the Khorramabad city have relative probiotic effect and that these lactic acid bacteria in fermented milk are suitable. PMID:25519007

  1. Acetic Acid Increases Stability of Silage under Aerobic Conditions

    PubMed Central

    Danner, H.; Holzer, M.; Mayrhuber, E.; Braun, R.

    2003-01-01

    The effects of various compounds on the aerobic stability of silages were evaluated. It has been observed that inoculation of whole-crop maize with homofermentative lactic acid bacteria leads to silages which have low stability against aerobic deterioration, while inoculation with heterofermentative lactic acid bacteria, such as Lactobacillus brevis or Lactobacillus buchneri, increases stability. Acetic acid has been proven to be the sole substance responsible for the increased aerobic stability, and this acid acts as an inhibitor of spoilage organisms. Therefore, stability increases exponentially with acetic acid concentration. Only butyric acid has a similar effect. Other compounds, like lactic acid, 1,2-propanediol, and 1-propanol, have been shown to have no effect, while fructose and mannitol reduce stability. PMID:12514042

  2. Viability of lactic acid bacteria and bifidobacteria in fermented soymilk after drying, subsequent rehydration and storage.

    PubMed

    Wang, Yi-Chieh; Yu, Roch-Chui; Chou, Cheng-Chun

    2004-06-01

    To develop a probiotic dietary adjunct, soymilk fermented with various combinations of lactic acid bacteria (Streptococcus thermophilus and Lactobacillus acidophilus) and bifidobacteria (Bifidobacterium longum and Bifidobacterium infantis) was subjected to freeze-drying and spray-drying. Survival of the starter organisms during the drying process, subsequent rehydration at different temperatures and during a 4-month period of storage under different storage conditions was examined. After freeze-drying, lactic acid bacteria and bifidobacteria exhibited a survival percent of 46.2-75.1% and 43.2-51.9%, respectively, higher than that noted after spray-drying. Regardless of the drying condition, S. thermophilus showed a higher percentage of survival than L. acidophilus, while B. longum survived better than B. infantis. Further study with soymilk fermented with S. thermophilus and B. longum revealed that the freeze-dried and spray-dried fermented soymilk rehydrated at 35-50 degrees C and 20 degrees C, respectively, was optimum for the recovery of the starter organisms. Both S. thermophilus and B. longum survived better in the freeze-dried than the spray-dried fermented soymilk during storage. A higher percent of survival was also noted for both the starter organisms when the dried fermented soymilk was stored at 4 degrees C than 25 degrees C. Holding the dried fermented soymilk in the laminated pouch enabled S. thermophilus and B. longum to exhibit a higher percentage of survival than in the deoxidant- and desiccant-containing glass or polyester (PET) bottle. Among all the packaging materials and storage temperatures tested, starter organisms were most stable in the dried fermented soymilk held in laminated pouch and stored at 4 degrees C. Under this storage condition, S. thermophilus and B. longum showed a survival percentage of 51.1% and 68.8%, respectively, in the freeze-dried fermented soymilk after 4 months of storage. Meanwhile, S. thermophilus and B. infantis in the spray-dried fermented soymilk showed a survival percent of 29.5% and 57.7%, respectively. PMID:15135959

  3. Phenotypic and molecular identification and clustering of lactic acid bacteria and yeasts from wheat (species Triticum durum and Triticum aestivum) sourdoughs of Southern Italy

    Microsoft Academic Search

    A. Corsetti; P. Lavermicocca; M. Morea; F. Baruzzi; N. Tosti; M. Gobbetti

    2001-01-01

    The microflora of 25 wheat sourdoughs from the Apulia region, Southern Italy, was characterized. The sourdoughs were mainly produced from Triticum durum wheat. The number of lactic acid bacteria and yeasts ranged from ca. log7.5 to log9.3 colony forming units (cfu)\\/g and from log5.5 to log8.4 cfu\\/g, respectively. About 38% of the 317 isolates of lactic acid bacteria were identified

  4. Identification of lactic acid bacteria associated with the production of plaa-som, a traditional fermented fish product of Thailand

    Microsoft Academic Search

    Phikunthong Kopermsub; Sirinda Yunchalard

    2010-01-01

    Plaa-som is a Thai fermented fish product for which whole fish or fish fillets are fermented with either cooked rice or steamed sticky rice, salt, and garlic. A total of 762 lactic acid bacteria (LAB) were isolated during plaa-som fermentation by culture on CaCO3-MRS agar plates. They were screened and grouped by amplified ribosomal DNA restriction analysis (ARDRA), giving six

  5. ???????????????????????????????????????????????????????????????? Escherichia coli ????????????????????????? ISOLATION AND SCREENING OF LACTIC ACID BACTERIA CAPABLE OF INHIBITING GROWTH OF SOME ESCHERICHIA COLI ISOLATED FROM SWINE

    Microsoft Academic Search

    Mongkhon Punyarat; Narumol Thongwai

    One hundred and forty-seven strains of lactic acid bacteria (LAB) were isolated from some soils, fermented foods, vegetables, fruits, milk and animal products. After cultivation in MRS broth at 37 ?C for 96 hours, each culture supernatant was evaluated its growth inhibitory activity by using a paper disc diffusion method against one strain of Escherichia coli O157:H7 and nine strains

  6. Atherosclerosis-Preventing Activity of Lactic Acid Bacteria-Fermented Milk?Soymilk Supplemented with Momordica charantia

    Microsoft Academic Search

    Tsung-Yu Tsai; Li-Han Chu; Chun-Lin Lee; Tzu-Ming Pan

    2009-01-01

    In this study, the milk-soymilk and milk-soymilk supplemented with Momordica charantia, a common oriental vegetable possessing medicinal activities, were fermented by lactic bacteria. The objective of this study was to investigate the effects of milk-soymilk and fermented milk-soymilk with or without M. charantia on atherosclerosis in hyperlipidemic hamsters. Fermented 25% milk and 75% soymilk combinations, supplemented with 1% M. charantia

  7. Phylogenetic Diversity of Lactic Acid Bacteria Associated with Paddy Rice Silage as Determined by 16S Ribosomal DNA Analysis

    Microsoft Academic Search

    Saïd Ennahar; Yimin Cai; Yasuhito Fujita

    2003-01-01

    A total of 161 low-GC-content gram-positive bacteria isolated from whole-crop paddy rice silage were classified and subjected to phenotypic and genetic analyses. Based on morphological and biochemical char- acters, these presumptive lactic acid bacterium (LAB) isolates were divided into 10 groups that included members of the genera Enterococcus, Lactobacillus, Lactococcus, Leuconostoc, Pediococcus, and Weissella. Analysis of the 16S ribosomal DNA

  8. Functional milk beverage fortified with phenolic compounds extracted from olive vegetation water, and fermented with functional lactic acid bacteria

    Microsoft Academic Search

    M. Servili; C. G. Rizzello; A. Taticchi; S. Esposto; S. Urbani; F. Mazzacane; I. Di Maio; R. Selvaggini; M. Gobbetti; R. Di Cagno

    2011-01-01

    Functional milk beverages (FMB100 and FMB200) fortified with phenolic compounds (100 and 200mg\\/l) extracted from olive vegetable water, and fermented with ?-amino butyric acid (GABA)-producing (Lactobacillus plantarum C48) and autochthonous human gastro-intestinal (Lactobacillus paracasei 15N) lactic acid bacteria were manufactured. A milk beverage (MB), without addition of phenolic compounds, was used as the control. Except for a longer latency phase

  9. Tina wooden vat biofilm: a safe and highly efficient lactic acid bacteria delivering system in PDO Ragusano cheese making.

    PubMed

    Lortal, Sylvie; Di Blasi, Annalisa; Madec, Marie-Noëlle; Pediliggieri, Concetta; Tuminello, Laura; Tanguy, Gaëlle; Fauquant, Jacques; Lecuona, Yohan; Campo, Patrizia; Carpino, Stefania; Licitra, Giuseppe

    2009-06-01

    In the Sicilian PDO Ragusano cheese making, raw milk is placed in a wooden vat called a Tina. As no starter is added, lactic acid is produced by milk flora and flora released from the Tina biofilm. The aim of this work was to assess the safety and efficiency of this natural inoculation system. From 15 Tinas' biofilms, bacteria total counts varied from 10(3) to 10(6) CFU/cm(2), with the predominance of thermophilic lactic acid bacteria. Low counts of yeasts and moulds were found in a few Tinas. Salmonella, Listeria monocytogenes, Escherichia coli O157:H7 were totally absent, as assessed by conventional plating and the Bax detection system after enrichment, highlighting the safety of the system. From four Tinas out of the 15, micropieces of wood were observed by confocal and scanning electron microscopy. The biofilm entrapped in a matrix covered almost entirely the surface of the wood. Polysaccharides were detected in the four Tinas. In three of the latter, cocci were predominant in the ecosystem whereas in the other one, cocci, bacilli, yeasts and moulds were observed. Fifty litres of microfiltrated milk (<10 CFU/mL) were poured in the four Tinas for 10 min of contact. Enumeration of lactic acid bacteria, yeasts and enterococci were performed in the milk after contact. Depending on the Tina, from 5.10(4) to 10(6) CFU/mL of Streptococcus thermophilus were released into the milk, and from 10(4) to 10(5) CFU/mL of thermophilic lactobacilli. Spontaneous acidification after contact confirmed the high efficiency of biofilm lactic acid bacteria delivery. PMID:19361876

  10. Diversity of lactic acid bacteria and yeasts in traditional sourdoughs collected from western region in Inner Mongolia of China

    Microsoft Academic Search

    Jiachao Zhang; Wenjun Liu; Zhihong Sun; Qiuhua Bao; Fang Wang; Jie Yu; Wei Chen; Heping Zhang

    2011-01-01

    Twenty-eight traditional sourdough samples for Chinese steamed breads were collected from the western region in Inner Mongolia of China. The values of pH and the total titratable acidity (TTA) of sourdoughs varied from 2.78–5.13 to 8.3–15.5 mL, respectively. In all samples, the number of lactic acid bacteria (LAB) ranged from 6.56 to 8.72 Log cfu\\/g, while the amount of yeasts ranged

  11. Phylogenetic group- and species-specific oligonucleotide probes for single-cell detection of lactic acid bacteria in oral biofilms

    Microsoft Academic Search

    Beatrice Quevedo; Elin Giertsen; Vincent Zijnge; Helga Lüthi-Schaller; Bernhard Guggenheim; Thomas Thurnheer; Rudolf Gmür

    2011-01-01

    BACKGROUND: The purpose of this study was to design and evaluate fluorescent in situ hybridization (FISH) probes for the single-cell detection and enumeration of lactic acid bacteria, in particular organisms belonging to the major phylogenetic groups and species of oral lactobacilli and to Abiotrophia\\/Granulicatella. RESULTS: As lactobacilli are known for notorious resistance to probe penetration, probe-specific assay protocols were experimentally

  12. Molecular and technological characterization of lactic acid bacteria from traditional fermented sausages of Basilicata region (Southern Italy)

    Microsoft Academic Search

    M. G. Bonomo; A. Ricciardi; T. Zotta; E. Parente; G. Salzano

    2008-01-01

    Lactic acid bacteria (LAB) from traditional fermented sausages of the Basilicata region were investigated by ARDRA-PCR and RAPD-PCR for taxonomic identification at species and strain level and characterized on the basis of the growth and acidification at different temperatures, incubation times, levels of NaCl and KNO2, hydrolysis of sarcoplasmatic and myofibrillar proteins and antimicrobial, peptide\\/amino acid release and nitrate reductase

  13. Synergistic and antagonistic effect of lactic acid bacteria on tyramine production by food-borne pathogenic bacteria in tyrosine decarboxylase broth

    Microsoft Academic Search

    Esmeray Kuley; Fatih Özogul

    2011-01-01

    The effect of lactic acid bacteria (LAB) strains on tyramine (TYR) and also other biogenic amines (BA) production by eight common food-borne pathogen (FBP) in tyrosine decarboxylase broth (TDB) was investigated by using a rapid HPLC method. Significant differences were observed among the FBP strains in ammonia (AMN) and BA production apart from tryptamine, histamine (HIS) and spermine formation (p<0.05).

  14. Development and quality of a Brazilian semi-hard goat cheese (coalho) with added probiotic lactic acid bacteria.

    PubMed

    Garcia, Estefânia Fernandes; de Oliveira, Maria Elieidy Gomes; Queiroga, Rita de Cássia Ramos Do Egypto; Machado, Tamires Alcântara Dourado; de Souza, Evandro Leite

    2012-12-01

    The effects of the addition of different strains of lactic acid bacteria on different quality parameters of a Brazilian goat semi-hard cheese (coalho) were assessed during 7 days of storage (10°C) as follows: Control, Lactobacillus lactis subsp. lactis and L. lactis subsp. cremoris (standard); C2, L. acidophilus; C3, L. paracasei; C4, Bifidobacterium lactis; and C5, L. acidophilus, L. paracasei and B. lactis. There were no differences for the proteolysis index and depth of proteolysis among the assessed cheeses. The cheeses presented increase in hardness, gumminess and chewiness during the storage. Regarding the ability to melt, all evaluated cheeses showed a reduction in diameter. Cheeses presented high luminosity with predominance of the yellow component; and number of lactic bacteria greater than 10?-10? cfu/g during the 7 days of storage. C5 had better sensory scores in the acceptance test, purchase intention and preference ranking test. Coalho goat cheese could be a potential carrier of probiotic lactic acid bacteria. PMID:22574688

  15. Antimicrobial interactions of microbial species involved in the fermentation of cassava dough into agbelima with particular reference to the inhibitory effect of lactic acid bacteria on enteric pathogens.

    PubMed

    Mante, Ebenezer Siaw; Sakyi-Dawson, Esther; Amoa-Awua, Wisdom Kofi

    2003-12-15

    Lactic acid bacteria, Bacillus species and yeasts are involved in the fermentation of cassava dough into agbelima. Microbial interactions within and between these groups of microorganisms were investigated in addition to the survival of five enteric pathogens inoculated into agbelima under various conditions. Nine out of 10 cultures of lactic acid bacteria isolated at the end of agbelima fermentation showed inhibitory effect against 10 cultures of lactic acid bacteria isolated at the start of fermentation. Only 3 out of 10 isolates of Bacillus subtilis were inhibited by 10 isolates of lactic acid bacteria tested. No interactions were observed between yeasts and the lactic acid bacteria, whereas three of the Bacillus isolates showed inhibitory effects against the yeasts. Twelve isolates of Lactobacillus plantarum tested inhibited the growth of an isolate each of Lactobacillus fermentum and Lactobacillus brevis but none tested positive for bacteriocin production. The antimicrobial effect of the lactic acid bacteria was attributed to acid production. In fermenting cassava dough, enteric pathogens survived to different extents depending on pH and their sensitivity to acids. Vibrio cholerae C-230, Salmonella typhimurium 9 and Salmonella enteritidis 226 were not detectable in 10 g of sample after 4 h when inoculated into the 48-h fermented product, agbelima, whereas Shigella dysenteriae 2357T and Escherichia coli D2188 were detectable up to 8 h in the product. PMID:14580972

  16. Abundance and Genetic Diversity of Aerobic Anoxygenic Phototrophic Bacteria of Coastal Regions of the Pacific Ocean

    PubMed Central

    Ritchie, Anna E.

    2012-01-01

    Aerobic anoxygenic phototrophic (AAP) bacteria are photoheterotrophic microbes that are found in a broad range of aquatic environments. Although potentially significant to the microbial ecology and biogeochemistry of marine ecosystems, their abundance and genetic diversity and the environmental variables that regulate these properties are poorly understood. Using samples along nearshore/offshore transects from five disparate islands in the Pacific Ocean (Oahu, Molokai, Futuna, Aniwa, and Lord Howe) and off California, we show that AAP bacteria, as quantified by the pufM gene biomarker, are most abundant near shore and in areas with high chlorophyll or Synechococcus abundance. These AAP bacterial populations are genetically diverse, with most members belonging to the alpha- or gammaproteobacterial groups and with subclades that are associated with specific environmental variables. The genetic diversity of AAP bacteria is structured along the nearshore/offshore transects in relation to environmental variables, and uncultured pufM gene libraries suggest that nearshore communities are distinct from those offshore. AAP bacterial communities are also genetically distinct between islands, such that the stations that are most distantly separated are the most genetically distinct. Together, these results demonstrate that environmental variables regulate both the abundance and diversity of AAP bacteria but that endemism may also be a contributing factor in structuring these communities. PMID:22307290

  17. Purple Sulfur Bacteria Control the Growth of Aerobic Heterotrophic Bacterioplankton in a Meromictic Salt Lake

    PubMed Central

    Overmann, J.; Beatty, J. T.; Hall, K. J.

    1996-01-01

    In meromictic Mahoney Lake, British Columbia, Canada, the heterotrophic bacterial production in the mixolimnion exceeded concomitant primary production by a factor of 7. Bacterial growth rates were correlated neither to primary production nor to the amount of chlorophyll a. Both results indicate an uncoupling of bacteria and phytoplankton. In the chemocline of the lake, an extremely dense population of the purple sulfur bacterium Amoebobacter purpureus is present year round. We investigated whether anoxygenic phototrophs are significant for the growth of aerobic bacterioplankton in the overlaying water. Bacterial growth rates in the mixolimnion were limited by inorganic phosphorus or nitrogen most of the time, and the biomass of heterotrophic bacteria did not increase until, in autumn, 86% of the cells of A. purpureus appeared in the mixolimnion because of their reduced buoyant density. The increase in heterotrophic bacterial biomass, soluble phosphorus concentrations below the detection limit, and an extraordinarily high activity of alkaline phosphatase in the mixolimnion indicate a rapid liberation of organically bound phosphorus from A. purpureus cells accompanied by a simultaneous incorporation into heterotrophic bacterioplankton. High concentrations of allochthonously derived dissolved organic carbon (mean, 60 mg of C(middot)liter(sup-1)) were measured in the lake water. In Mahoney Lake, liberation of phosphorus from upwelling purple sulfur bacteria and degradation of allochthonous dissolved organic carbon as an additional carbon source render heterotrophic bacterial production largely independent of the photosynthesis of phytoplankton. A recycling of inorganic nutrients via phototrophic bacteria also appears to be relevant in other lakes with anoxic bottom waters. PMID:16535399

  18. Characterization of lactic acid bacteria from naturally-fermented Manzanilla Aloreña green table olives.

    PubMed

    Abriouel, Hikmate; Benomar, Nabil; Cobo, Antonio; Caballero, Natacha; Fernández Fuentes, Miguel Ángel; Pérez-Pulido, Rubén; Gálvez, Antonio

    2012-12-01

    Manzanilla Aloreña (or Aloreña) table olives are naturally fermented traditional green olives with a denomination of protection (DOP). The aim of this study was to search for lactic acid bacteria (LAB) with technological properties of interest for possible inclusion in a starter or protective culture preparation or also as probiotics. A collection of 144 LAB obtained from Aloreña green table olives naturally-fermented by four small-medium enterprises (SMEs) from Málaga (Spain), including lactobacilli (81.94%), leuconostocs (10.42%) and pediococci (7.64%) were studied. REP-PCR clustering and further identification of strains by sequencing of phes and rpo genes revealed that all lactobacilli from the different SMEs were Lactobacillus pentosus. Pediococci were identified as Pediococcus parvulus (SME1) and leuconostocs as Leuconostoc pseudomesenteroides (SME1 and SME4). Genotyping revealed that strains were not clonally related and exhibited a considerable degree of genomic diversity specially for lactobacilli and also for leuconostocs. Some strains exhibit useful technological properties such as production of antimicrobial substances active against pathogenic bacteria such as Listeria monocytogenes, Bacillus cereus, Staphylococcus aureus, Streptococcus mutans and Salmonella enterica, utilization of raffinose and stachyose, production of bile salt hydrolase, phytase and haeme-dependent catalase activities, growth at 10 °C and in the presence of 6.5% NaCl, good acidifying capacity and also resistance to freezing. However, none of the isolates showed protease or amylase activity, and also did not exhibit biogenic amine production from histidine, ornithine, cysteine or tyrosine. On the basis of data obtained, selected strains with potential traits were tested for their survival at low pH and their tolerance to bile salts, and the survival capacity demonstrated by some of the analysed strains are encouraging to further study their potential as probiotics. PMID:22986194

  19. In Vitro Study of Potentially Probiotic lactic Acid Bacteria Strains Isolated From Traditional Dairy Products

    PubMed Central

    Niazi Amraii, Hooshang; Abtahi, Hamid; Jafari, Parvaneh; Mohajerani, Hamid Reza; Fakhroleslam, Mohammad Reza; Akbari, Neda

    2014-01-01

    Background: Probiotic microorganisms are selected based on their long history of use as well as their lack of side effects. Nowadays, the consumption of probiotic products is growing intensively in developing countries. Researchers who work in the food industry and research centers pay more attention to the identification of new probiotic bacteria with better performance characteristics as well as investigation of their performance because these findings can be very effective in promoting sale and consumption of these products. Objectives: Hence, this study was performed following these objectives: isolating indigenous lactic acid bacteria from traditional dairy products in Markazi Province, screening strains with probiotic characteristics, identifying strains and performing microbial collection of probiotic strains with indigenous potential. Materials and Methods: In this study, the samples were screened from traditional dairy products, such as fresh yogurt, curd, Tarhana and Ghareghoroot of Markazi Province villages. Samples were enriched in de Man, Rogosa and Sharpe (MRS) broth, and different strains were isolated and purified from this culture on MRS agar medium. Isolated strains were investigated by microscopic observations, considering the following factors: catalase capability, resistance to acid and bile, bile salt hydrolysis and antibiotic susceptibility pattern. Results: Nineteen Gram-positive and catalase-negative strains belonging to the Lactobacillus genus were isolated from the above-mentioned diary samples. Seven strains were resistant to acid and bile in which acid resistance was between 21.08% and 122.33% and bile resistance was between 94.08% and 152.93%, respectively. All isolated strains were susceptible to different antibiotics and a small percentage had the ability to hydrolyze Sodium Taurocholate. Conclusions: There are many of different species of Lactobacillus probiotics in traditional dairy products of the Markazi province, based on the findings of this study. It is recommended for researchers to isolate these strains and investigate their probiotic characteristics in order to reproduce them for use in food production as well as for medical treatment. PMID:25371793

  20. Lactic acid bacteria and yeasts involved in the fermentation ofamabere amaruranu, a Kenyan fermented milk.

    PubMed

    Nyambane, Bitutu; Thari, William M; Wangoh, John; Njage, Patrick M K

    2014-11-01

    Indigenous fermented milk products contain microbiota composed of technologically important species and strains which are gradually getting lost with new technologies. We investigated the microbial diversity inamabere amaruranu, a traditionally fermented milk product from Kenya. Sixteen samples of the product from different containers were obtained. One hundred and twenty isolates of lactic acid bacteria (LAB) and 67 strains of yeasts were identified using API 50 CH and API 20 C AUX identification kits, respectively. The average pH of all the traditional fermented samples was 4.00 ± 0.93. Lactobacilli, yeasts, and molds as well asEnterobacteriaceae counts from the plastic containers were significantly higher (P < 0.05) than those from gourd.Enterobacteriaceae were below 1.00 ± 1.11 log10 cfu/mL in products from the gourds and 2.17 ± 1.92 log10 cfu/mL from the plastic containers. The LAB species were identified asStreptococcus thermophilus (25%),Lactobacillus plantarum (20%), andLeuconostoc mesenteroides (20%). The predominant yeasts wereSaccharomyces cerevisiae (25%),Trichosporum mucoides (15%),Candida famata (10%), andCandida albicans (10%). The type of vessel used for fermentation had no significant influence on the type of isolated and identified species. The diverse mixture of LAB and yeasts microflora forms a potential consortium for further product innovation inamabere amaruranu and other fermented milk products. PMID:25493187

  1. Control of spoilage fungi by protective lactic acid bacteria displaying probiotic properties.

    PubMed

    Varsha, Kontham Kulangara; Priya, Sulochana; Devendra, Leena; Nampoothiri, Kesavan Madhavan

    2014-04-01

    Thirty-six lactic acid bacteria belong to Lactococcus, Lactobacillus, Enterococcus, and Pediococcus were isolated, and the spectrum of antifungal activity was verified against Fusarium oxysporum (KACC 42109), Aspergillus niger (KACC 42589), Fusarium moniliforme (KACC 08141), Penicillium chrysogenum (NII 08137), and the yeast Candida albicans (MTCC 3017). Three isolates, identified as Pediococcus pentosaceus (TG2), Lactobacillus casei (DY2), and Lactococcus (BSN) were selected further, and their antifungal compounds were identified by ESI-MS and HPLC analysis as a range of carboxylic acids along with some unidentified, higher molecular weight compounds. An attempt to check out the shelf life extension of wheat bread without fungal spoilage was performed by fermenting the dough with the Lactococcus isolate. Apart from growth in low pH and tolerance to bile salts, probiotic potential of these three isolates was further substantiated by in vitro screening methods that include transit tolerance to the conditions in the upper human gastrointestinal tract and bacterial adhesion capacity to human intestinal cell lines. PMID:24532445

  2. Cereal fungal infection, mycotoxins, and lactic acid bacteria mediated bioprotection: from crop farming to cereal products.

    PubMed

    Oliveira, Pedro M; Zannini, Emanuele; Arendt, Elke K

    2014-02-01

    Lactic acid bacteria (LAB) metabolites are a reliable alternative for reducing fungal infections pre-/post-harvest with additional advantages for cereal-base products which convene the food market's trend. Grain industrial use is in expansion owing to its applicability in generating functional food. The food market is directed towards functional natural food with clear health benefits for the consumer in detriment to chemical additives. The food market chain is becoming broader and more complex, which presents an ever-growing fungal threat. Toxigenic and spoilage fungi are responsible for numerous diseases and economic losses. Cereal infections may occur in the field or post-processing, along the food chain. Consequently, the investigation of LAB metabolites with antifungal activity has gained prominence in the scientific research community. LAB bioprotection retards the development of fungal diseases in the field and inhibit pathogens and spoilage fungi in food products. In addition to the health safety improvement, LAB metabolites also enhance shelf-life, organoleptic and texture qualities of cereal-base foods. This review presents an overview of the fungal impact through the cereal food chain leading to investigation on LAB antifungal compounds. Applicability of LAB in plant protection and cereal industry is discussed. Specific case studies include Fusarium head blight, malting and baking. PMID:24230476

  3. Lactic Acid Bacteria Strains Exert Immunostimulatory Effect on H. pylori-Induced Dendritic Cells

    PubMed Central

    Wiese, Ma?gorzata; Andryszczyk, Marek; Motyl, Ilona; Wieczy?ska, Jolanta; Gackowska, Lidia; Micha?kiewicz, Jacek

    2015-01-01

    The aim of this study was to find out if selected lactic acid bacteria (LAB) strains (antagonistic or nonantagonistic against H. pylori in vitro) would differ in their abilities to modulate the DCs maturation profiles reflected by their phenotype and cytokine expression patterns. Methods. Monocyte-derived DCs maturation was elicited by their direct exposure to the LAB strains of L. rhamnosus 900 or L. paracasei 915 (antagonistic and nonantagonistic to H. pylori, resp.), in the presence or absence of H. pylori strain cagA+. The DCs maturation profile was assessed on the basis of surface markers expression and cytokines production. Results. We observed that the LAB strains and the mixtures of LAB with H. pylori are able to induce mature DCs. At the same time, the L. paracasei 915 leads to high IL-10/IL-12p70 cytokine ratio, in contrast to L. rhamnosus 900. Conclusions. This study showed that the analyzed lactobacilli strains are more potent stimulators of DC maturation than H. pylori. Interestingly from the two chosen LAB strains the antagonistic to H. pylori-L. rhamnosus strain 900 has more proinflammatory and probably antibactericidal properties. PMID:25759836

  4. Antibiotic resistance in lactic acid bacteria isolated from some pharmaceutical and dairy products

    PubMed Central

    Gad, Gamal Fadl M.; Abdel-Hamid, Ahmed M.; Farag, Zeinab Shawky H.

    2014-01-01

    A total of 244 lactic acid bacteria (LAB) strains were isolated from 180 dairy and pharmaceutical products that were collected from different areas in Minia governorate, Egypt. LAB were identified phenotypically on basis of morphological, physiological and biochemical characteristics. Lactobacillus isolates were further confirmed using PCR-based assay. By combination of phenotypic with molecular identification Lactobacillus spp. were found to be the dominant genus (138, 76.7%) followed by Streptococcus spp. (65, 36.1%) and Lactococcus spp. (27, 15%). Some contaminant organisms such as (Staphylococcus spp., Escherichia coli, Salmonella spp., mould and yeast) were isolated from the collected dairy samples but pharmaceutical products were free of such contaminants. Susceptibility of LAB isolates to antibiotics representing all major classes was tested by agar dilution method. Generally, LAB were highly susceptible to Beta-lactams except penicillin. Lactobacilli were resistant to vancomycin, however lactococci and streptococci proved to be very susceptible. Most strains were susceptible to tetracycline and showed a wide range of streptomycin MICs. The MICs of erythromycin and clindamycin for most of the LAB were within the normal range of susceptibility. Sixteen Lactobacillus, 8 Lactococcus and 8 Streptococcus isolates including all tetracycline and/or erythromycin resistant strains were tested for the presence of tetracycline and/or erythromycin resistant genes [tet(M) and/or erm(B)]. PCR assays shows that some resistant strains harbor tet(M) and/or erm(B) resistance genes. PMID:24948910

  5. Effects of lactic acid bacteria isolated from fermented mustard on lowering cholesterol

    PubMed Central

    Wang, Shu Chen; Chang, Chen Kai; Chan, Shu Chang; Shieh, Jiunn Shiuh; Chiu, Chih Kwang; Duh, Pin-Der

    2014-01-01

    Objective To evaluate the ability of lactic acid bacteria (LAB) strains isolated from fermented mustard to lower the cholesterol in vitro. Methods The ability of 50 LAB strains isolated from fermented mustard on lowering cholesterol in vitro was determined by modified o-phtshalaldehyde method. The LAB isolates were analyzed for their resistance to acid and bile salt. Strains with lowering cholesterol activity, were determined adherence to Caco-2 cells. Results Strain B0007, B0006 and B0022 assimilated more cholesterol than BCRC10474 and BCRC 17010. The isolated strains showed tolerance to pH 3.0 for 3 h despite variations in the degree of viability and bile-tolerant strains, with more than 108 CFU/mL after incubation for 24 h at 1% oxigall in MRS. In addition, strain B0007 and B0022 identified as Lactobacillus plantarum with 16S rDNA sequences were able to adhere to the Caco-2 cell lines. Conclusions These strains B0007 and B0022 may be potential functional sources for cholesterol-lowering activities as well as adhering to Caco-2 cell lines. PMID:25183271

  6. Comparison of homo- and heterofermentative lactic acid bacteria for implementation of fermented wheat bran in bread.

    PubMed

    Prückler, Michael; Lorenz, Cindy; Endo, Akihito; Kraler, Manuel; Dürrschmid, Klaus; Hendriks, Karel; Soares da Silva, Francisco; Auterith, Eric; Kneifel, Wolfgang; Michlmayr, Herbert

    2015-08-01

    Despite its potential health benefits, the integration of wheat bran into the food sector is difficult due to several adverse technological and sensory properties such as bitterness and grittiness. Sourdough fermentation is a promising strategy to improve the sensory quality of bran without inducing severe changes to the bran matrix. Therefore, identification of species/strains with potential for industrial sourdough fermentations is important. We compared the effects of different representatives of species of lactic acid bacteria (LAB) on wheat bran. Lactobacillus plantarum, Lactobacillus pentosus, Lactobacillus brevis, Lactobacillus sanfranciscensis and Fructobacillus fructosus produced highly individual fermentation patterns as judged from carbohydrate consumption and organic acid production. Interestingly, fructose was released during all bran fermentations and possibly influenced the fermentation profiles of obligately heterofermentative species to varying degrees. Except for the reduction of ferulic acid by L. plantarum and L. pentosus, analyses of phenolic compounds and alkylresorcinols suggested that only minor changes thereof were induced by the LAB metabolism. Sensory analysis of breads baked with fermented bran did not reveal significant differences regarding perceived bitterness and aftertaste. We conclude that in addition to more traditionally used sourdough species such as L. sanfranciscensis and L. brevis, also facultatively heterofermentative species such as L. plantarum and L. pentosus possess potential for industrial wheat bran fermentations and should be considered in further investigations. PMID:25846933

  7. Oenococcus alcoholitolerans sp. nov., a lactic acid bacteria isolated from cachaça and ethanol fermentation processes.

    PubMed

    Badotti, Fernanda; Moreira, Ana Paula B; Tonon, Luciane A Chimetto; de Lucena, Brígida T Luckwu; Gomes, Fátima de Cássia O; Kruger, Ricardo; Thompson, Cristiane C; de Morais, Marcos Antonio; Rosa, Carlos A; Thompson, Fabiano L

    2014-12-01

    Four strains of lactic acid bacteria isolated from cachaça and alcohol fermentation vats in Brazil were characterised in order to determine their taxonomic position. Phylogenetic analysis revealed that they belong to the genus Oenococcus and should be distinguished from their closest neighbours. The 16S rRNA gene sequence similarity against the type strains of the other two species of the genus was below 94.76 % (Oenococcus kitaharae) and 94.62 % (Oenococcus oeni). The phylogeny based on pheS gene sequences also confirmed the position of the new taxon. DNA-DNA hybridizations based on in silico genome-to-genome comparison, Average Amino Acid Identity, Average Nucleotide Identity and Karlin genomic signature confirmed the novelty of the taxon. Distinctive phenotypic characteristics are the ability to metabolise sucrose but not trehalose. The name Oenococcus alcoholitolerans sp. nov. is proposed for this taxon, with the type strain UFRJ-M7.2.18(T) ( = CBAS474(T) = LMG27599(T)). In addition, we have determined a draft genome sequence of the type strain. PMID:25315101

  8. Genetic and Technological Characterisation of Vineyard- and Winery-Associated Lactic Acid Bacteria

    PubMed Central

    Nisiotou, Aspasia A.; Filippousi, Maria-Evangelia; Fragkoulis, Petros; Tassou, Chryssoula; Banilas, Georgios

    2015-01-01

    Vineyard- and winery-associated lactic acid bacteria (LAB) from two major PDO regions in Greece, Peza and Nemea, were surveyed. LAB were isolated from grapes, fermenting musts, and winery tanks performing spontaneous malolactic fermentations (MLF). Higher population density and species richness were detected in Nemea than in Peza vineyards and on grapes than in fermenting musts. Pediococcus pentosaceus and Lactobacillus graminis were the most abundant LAB on grapes, while Lactobacillus plantarum dominated in fermenting musts from both regions. No particular structure of Lactobacillus plantarum populations according to the region of origin was observed, and strain distribution seems random. LAB species diversity in winery tanks differed significantly from that in vineyard samples, consisting principally of Oenococcus oeni. Different strains were analysed as per their enological characteristics and the ability to produce biogenic amines (BAs). Winery-associated species showed higher resistance to low pH, ethanol, SO2, and CuSO4 than vineyard-associated isolates. The frequency of BA-producing strains was relatively low but not negligible, considering that certain winery-associated Lactobacillus hilgardii strains were able to produce BAs. Present results show the necessity of controlling the MLF by selected starters in order to avoid BA accumulation in wine.

  9. Inhibition of Paenibacillus larvae by lactic acid bacteria isolated from fermented materials.

    PubMed

    Yoshiyama, Mikio; Wu, Meihua; Sugimura, Yuya; Takaya, Noriko; Kimoto-Nira, Hiromi; Suzuki, Chise

    2013-01-01

    We evaluated the potential application of lactic acid bacteria (LAB) isolated from fermented feeds and foods for use as probiotics against Paenibacillus larvae, the causal agent of American foulbrood (AFB) in vitro. We also assessed the ability of LAB to induce the expression of antimicrobial peptide genes in vivo. Screening of the 208 LAB isolated from fermented feeds and foods revealed that nine strains inhibited the in vitro growth of P. larvae. The LAB strains were identified by 16S rRNA gene sequencing as Enterococcus sp., Weissella sp. and Lactobacillus sp. These strains were screened for their abilities of immune activation in honeybees by real-time RT-PCR using antimicrobial peptide genes as markers. After oral administration of several of the screened LAB to larvae and adults, the transcription levels of antimicrobial peptide genes, such as abaecin, defensin and hymenoptaecin, were found to increase significantly. These findings suggested that selected LAB stimulate the innate immune response in honeybees, which may be useful for preventing bacterial diseases in honeybees. This is the first report to characterize the probiotic effects of LAB isolated from fermented feeds and foods in honeybees. PMID:23000777

  10. The effect of marination on lactic acid bacteria communities in raw broiler fillet strips.

    PubMed

    Nieminen, T T; Välitalo, H; Säde, E; Paloranta, A; Koskinen, K; Björkroth, J

    2012-01-01

    Marination with marinade containing salt, sugar, and acetic acid is commonly used in Finland to enhance the value of raw broiler meat. In this study, we investigated the effect of marination, marinade components and storage time on composition of bacterial communities in modified atmosphere-packaged (MAP) broiler fillet strips. The communities were characterized using two culture-independent methods: 16S rRNA gene fragment sequencing and terminal restriction fragment length polymorphism. In unmarinated broiler fillet strips, Lactococcus spp. and Carnobacterium spp. predominated at the early storage phase but were partially replaced by Lactobacillus spp. and Leuconostoc spp. when the chilled storage time was extended. In the marinated fillet strips, Lactobacillus spp. and Leuconostoc spp. predominated independent from the storage time. By mixing the different marinade components with broiler meat, we showed that marination changed the community composition and favored Leuconostoc spp. and Lactobacillus spp. by the combined effect of carbohydrates and acetic acid in marinade. Marination increased the maximum level of lactic acid bacteria in broiler meat and enhanced CO(2) production and acidification of meat during the chilled storage. Accumulation of CO(2) in package head-space due to the enhanced growth of Leuconostoc spp. in marinated meat may lead to bulging of packages, which is a spoilage defect frequently associated with marinated and MAP raw broiler preparations in Finland. PMID:23087685

  11. The effect of marination on lactic acid bacteria communities in raw broiler fillet strips

    PubMed Central

    Nieminen, T. T.; Välitalo, H.; Säde, E.; Paloranta, A.; Koskinen, K.; Björkroth, J.

    2012-01-01

    Marination with marinade containing salt, sugar, and acetic acid is commonly used in Finland to enhance the value of raw broiler meat. In this study, we investigated the effect of marination, marinade components and storage time on composition of bacterial communities in modified atmosphere-packaged (MAP) broiler fillet strips. The communities were characterized using two culture-independent methods: 16S rRNA gene fragment sequencing and terminal restriction fragment length polymorphism. In unmarinated broiler fillet strips, Lactococcus spp. and Carnobacterium spp. predominated at the early storage phase but were partially replaced by Lactobacillus spp. and Leuconostoc spp. when the chilled storage time was extended. In the marinated fillet strips, Lactobacillus spp. and Leuconostoc spp. predominated independent from the storage time. By mixing the different marinade components with broiler meat, we showed that marination changed the community composition and favored Leuconostoc spp. and Lactobacillus spp. by the combined effect of carbohydrates and acetic acid in marinade. Marination increased the maximum level of lactic acid bacteria in broiler meat and enhanced CO2 production and acidification of meat during the chilled storage. Accumulation of CO2 in package head-space due to the enhanced growth of Leuconostoc spp. in marinated meat may lead to bulging of packages, which is a spoilage defect frequently associated with marinated and MAP raw broiler preparations in Finland. PMID:23087685

  12. Interaction of Aeromonas Strains with Lactic Acid Bacteria via Caco-2 Cells

    PubMed Central

    Hatje, E.; Neuman, C.

    2014-01-01

    The genus Aeromonas includes some species that have now been identified as human pathogens of significant medical importance. We investigated the ability of 13 selected Aeromonas strains belonging to nine species isolated from clinical cases (n = 5), environmental waters (n = 5), and fish (n = 3) to adhere to and translocate Caco-2 cells in the absence and presence of two lactic acid bacteria (LAB), i.e., Lactobacillus acidophilus and Bifidobacterium breve. Aeromonas isolates were also assessed for their cytotoxicity, the presence of virulence genes, and hemolysin production. Among the clinical isolates, one strain of Aeromonas veronii biovar veronii and two strains of Aeromonas hydrophila carried cytotoxin (act), heat-labile toxin (alt), hemolysin (hlyA), and aerolysin (aerA) genes, were cytotoxic to Vero cells, produced hemolysin, and showed higher adherence to Caco-2 cells. In contrast, this was seen in only one environmental strain, a strain of A. veronii biovar sobria. When Aeromonas strains were coinoculated with LAB onto Caco-2 cells, their level of adhesion was reduced. However, their rate of translocation in the presence of LAB increased and was significantly (P < 0.05) higher among fish strains. We suggest that either the interaction between Aeromonas and LAB strains could have a detrimental effect on the Caco-2 cells, allowing the Aeromonas to translocate more readily, or the presence of the LAB stimulated the Aeromonas strains to produce more toxins and/or increase their translocation rate. PMID:24242240

  13. Lactic acid bacteria and yeasts involved in the fermentation ofamabere amaruranu, a Kenyan fermented milk

    PubMed Central

    Nyambane, Bitutu; Thari, William M; Wangoh, John; Njage, Patrick M K

    2014-01-01

    Indigenous fermented milk products contain microbiota composed of technologically important species and strains which are gradually getting lost with new technologies. We investigated the microbial diversity inamabere amaruranu, a traditionally fermented milk product from Kenya. Sixteen samples of the product from different containers were obtained. One hundred and twenty isolates of lactic acid bacteria (LAB) and 67 strains of yeasts were identified using API 50 CH and API 20 C AUX identification kits, respectively. The average pH of all the traditional fermented samples was 4.00 ± 0.93. Lactobacilli, yeasts, and molds as well asEnterobacteriaceae counts from the plastic containers were significantly higher (P < 0.05) than those from gourd.Enterobacteriaceae were below 1.00 ± 1.11 log10 cfu/mL in products from the gourds and 2.17 ± 1.92 log10 cfu/mL from the plastic containers. The LAB species were identified asStreptococcus thermophilus (25%),Lactobacillus plantarum (20%), andLeuconostoc mesenteroides (20%). The predominant yeasts wereSaccharomyces cerevisiae (25%),Trichosporum mucoides (15%),Candida famata (10%), andCandida albicans (10%). The type of vessel used for fermentation had no significant influence on the type of isolated and identified species. The diverse mixture of LAB and yeasts microflora forms a potential consortium for further product innovation inamabere amaruranu and other fermented milk products. PMID:25493187

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

    PubMed Central

    Pereira, Dora I. A.; Gibson, Glenn R.

    2002-01-01

    The objective of this study was to evaluate the effect of human gut-derived lactic acid bacteria and bifidobacteria on cholesterol levels in vitro. Continuous cultures inoculated with fecal material from healthy human volunteers with media supplemented with cholesterol and bile acids were used to enrich for potential cholesterol assimilators among the indigenous bacterial populations. Seven potential probiotics were found: Lactobacillus fermentum strains F53 and KC5b, Bifidobacterium infantis ATCC 15697, Streptococcus bovis ATCC 43143, Enterococcus durans DSM 20633, Enterococcus gallinarum, and Enterococcus faecalis. A comparative evaluation regarding the in vitro cholesterol reduction abilities of these strains along with commercial probiotics was undertaken. The degree of acid and bile tolerance of strains was also evaluated. The human isolate L. fermentum KC5b was able to maintain viability for 2 h at pH 2 and to grow in a medium with 4,000 mg of bile acids per liter. This strain was also able to remove a maximum of 14.8 mg of cholesterol per g (dry weight) of cells from the culture medium and therefore was regarded as a candidate probiotic. PMID:12200334

  15. Monitoring psychrotrophic lactic acid bacteria contamination in a ready-to-eat vegetable salad production environment.

    PubMed

    Pothakos, Vasileios; Snauwaert, Cindy; De Vos, Paul; Huys, Geert; Devlieghere, Frank

    2014-08-18

    A study monitoring lactic acid bacteria contamination was conducted in a company producing fresh, minimally processed, packaged and ready-to-eat (RTE) vegetable salads (stored at 4°C) in order to investigate the reason for high psychrotrophic LAB levels in the products at the end of shelf-life. Initially, high microbial counts exceeding the established psychrotrophic thresholds (>10(7)-10(8)CFU/g) and spoilage manifestations before the end of the shelf-life (7days) occurred in products containing an assortment of sliced and diced vegetables, but within a one year period these spoilage defects became prevalent in the entire processing plant. Environmental sampling and microbiological analyses of the raw materials and final products throughout the manufacturing process highlighted the presence of high numbers of Leuconostoc spp. in halved and unseeded, fresh sweet bell peppers provided by the supplier. A combination of two DNA fingerprinting techniques facilitated the assessment of the species diversity of LAB present in the processing environment along with the critical point of their introduction in the production facility. Probably through air mediation and surface adhesion, mainly members of the strictly psychrotrophic species Leuconostoc gelidum subsp. gasicomitatum and L. gelidum subsp. gelidum were responsible for the cross-contamination of every vegetable handled within the plant. PMID:24927398

  16. Significant effect of Ca2+ on improving the heat resistance of lactic acid bacteria.

    PubMed

    Huang, Song; Chen, Xiao Dong

    2013-07-01

    The heat resistance of lactic acid bacteria (LAB) has been extensively investigated due to its highly practical significance. Reconstituted skim milk (RSM) has been found to be one of the most effective protectant wall materials for microencapsulating microorganisms during convective drying, such as spray drying. In addition to proteins and carbohydrate, RSM is rich in calcium. It is not clear which component is critical in the RSM protection mechanism. This study investigated the independent effect of calcium. Ca(2+) was added to lactose solution to examine its influence on the heat resistance of Lactobacillus rhamnosus ZY, Lactobacillus casei Zhang, Lactobacillus plantarum P8 and Streptococcus thermophilus ND03. The results showed that certain Ca(2+) concentrations enhanced the heat resistance of the LAB strains to different extents, that is produced higher survival and shorter regrowth lag times of the bacterial cells. In some cases, the improvements were dramatic. More scientifically insightful and more intensive instrumental study of the Ca(2+) behavior around and in the cells should be carried out in the near future. In the meantime, this work may lead to the development of more cost-effective wall materials with Ca(2+) added as a prime factor. PMID:23617813

  17. Symbionts as Major Modulators of Insect Health: Lactic Acid Bacteria and Honeybees

    PubMed Central

    Vásquez, Alejandra; Forsgren, Eva; Fries, Ingemar; Paxton, Robert J.; Flaberg, Emilie; Szekely, Laszlo

    2012-01-01

    Lactic acid bacteria (LAB) are well recognized beneficial host-associated members of the microbiota of humans and animals. Yet LAB-associations of invertebrates have been poorly characterized and their functions remain obscure. Here we show that honeybees possess an abundant, diverse and ancient LAB microbiota in their honey crop with beneficial effects for bee health, defending them against microbial threats. Our studies of LAB in all extant honeybee species plus related apid bees reveal one of the largest collections of novel species from the genera Lactobacillus and Bifidobacterium ever discovered within a single insect and suggest a long (>80 mya) history of association. Bee associated microbiotas highlight Lactobacillus kunkeei as the dominant LAB member. Those showing potent antimicrobial properties are acquired by callow honey bee workers from nestmates and maintained within the crop in biofilms, though beekeeping management practices can negatively impact this microbiota. Prophylactic practices that enhance LAB, or supplementary feeding of LAB, may serve in integrated approaches to sustainable pollinator service provision. We anticipate this microbiota will become central to studies on honeybee health, including colony collapse disorder, and act as an exemplar case of insect-microbe symbiosis. PMID:22427985

  18. Design of a protein-targeting system for lactic acid bacteria.

    PubMed

    Dieye, Y; Usai, S; Clier, F; Gruss, A; Piard, J C

    2001-07-01

    We designed an expression and export system that enabled the targeting of a reporter protein (the staphylococcal nuclease Nuc) to specific locations in Lactococcus lactis cells, i.e., cytoplasm, cell wall, or medium. Optimization of protein secretion and of protein cell wall anchoring was performed with L. lactis cells by modifying the signals located at the N and C termini, respectively, of the reporter protein. Efficient translocation of precursor (approximately 95%) is obtained using the signal peptide from the lactococcal Usp45 protein and provided that the mature protein is fused to overall anionic amino acids at its N terminus; those residues prevented interactions of Nuc with the cell envelope. Nuc could be covalently anchored to the peptidoglycan by using the cell wall anchor motif of the Streptococcus pyogenes M6 protein. However, the anchoring step proved to not be totally efficient in L. lactis, as considerable amounts of protein remained membrane associated. Our results may suggest that the defect is due to limiting sortase in the cell. The optimized expression and export vectors also allowed secretion and cell wall anchoring of Nuc in food-fermenting and commensal strains of Lactobacillus. In all strains tested, both secreted and cell wall-anchored Nuc was enzymatically active, suggesting proper enzyme folding in the different locations. These results provide the first report of a targeting system in lactic acid bacteria in which the final location of a protein is controlled and biological activity is maintained. PMID:11418555

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

    PubMed Central

    Russo, Pasquale; de Chiara, Maria Lucia Valeria; Vernile, Anna; Amodio, Maria Luisa; Arena, Mattia Pia; Capozzi, Vittorio; Massa, Salvatore; Spano, Giuseppe

    2014-01-01

    Due to the increasing interest for healthy foods, the feasibility of using fresh-cut fruits to vehicle probiotic microorganisms is arising scientific interest. With this aim, the survival of probiotic lactic acid bacteria, belonging to Lactobacillus plantarum and Lactobacillus fermentum species, was monitored on artificially inoculated pineapple pieces throughout storage. The main nutritional, physicochemical, and sensorial parameters of minimally processed pineapples were monitored. Finally, probiotic Lactobacillus were further investigated for their antagonistic effect against Listeria monocytogenes and Escherichia coli O157:H7 on pineapple plugs. Our results show that at eight days of storage, the concentration of L. plantarum and L. fermentum on pineapples pieces ranged between 7.3 and 6.3?log?cfu?g?1, respectively, without affecting the final quality of the fresh-cut pineapple. The antagonistic assays indicated that L. plantarum was able to inhibit the growth of both pathogens, while L. fermentum was effective only against L. monocytogenes. This study suggests that both L. plantarum and L. fermentum could be successfully applied during processing of fresh-cut pineapples, contributing at the same time to inducing a protective effect against relevant foodborne pathogens. PMID:25093163

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

    PubMed Central

    Lee, Do Kyung; Jang, Seok; Baek, Eun Hye; Kim, Mi Jin; Lee, Kyung Soon; Shin, Hea Soon; Chung, Myung Jun; Kim, Jin Eung; Lee, Kang Oh; Ha, Nam Joo

    2009-01-01

    Background Lactic acid bacteria (LAB) are beneficial probiotic organisms that contribute to improved nutrition, microbial balance, and immuno-enhancement of the intestinal tract, as well as lower cholesterol. Although present in many foods, most trials have been in spreads or dairy products. Here we tested whether Bifidobacteria isolates could lower cholesterol, inhibit harmful enzyme activities, and control fecal water content. Methods In vitro culture experiments were performed to evaluate the ability of Bifidobacterium spp. isolated from healthy Koreans (20~30 years old) to reduce cholesterol-levels in MRS broth containing polyoxyethanylcholesterol sebacate. Animal experiments were performed to investigate the effects on lowering cholesterol, inhibiting harmful enzyme activities, and controlling fecal water content. For animal studies, 0.2 ml of the selected strain cultures (108~109 CFU/ml) were orally administered to SD rats (fed a high-cholesterol diet) every day for 2 weeks. Results B. longum SPM1207 reduced serum total cholesterol and LDL levels significantly (p < 0.05), and slightly increased serum HDL. B. longum SPM1207 also increased fecal LAB levels and fecal water content, and reduced body weight and harmful intestinal enzyme activities. Conclusion Daily consumption of B. longum SPM1207 can help in managing mild to moderate hypercholesterolemia, with potential to improve human health by helping to prevent colon cancer and constipation. PMID:19515264

  1. Production of 2-butanol through meso-2,3-butanediol consumption in lactic acid bacteria.

    PubMed

    Ghiaci, Payam; Lameiras, Francisca; Norbeck, Joakim; Larsson, Christer

    2014-11-01

    2-Butanol has been an issue of industries in many areas, for example, biofuel production (as an advanced alternate fuel), fermented beverages, and food (as taste-altering component). Thus, its source of production, the biological pathway, and the enzymes involved are of high interest. In this study, 42 different isolates of lactic acid bacteria from nine different species were screened for their capability to consume meso-2,3-butanediol and produce 2-butanol. Lactobacillus brevis was the only species that showed any production of 2-butanol. Five of ten tested isolates of L. brevis were able to convert meso-2,3-butanediol to 2-butanol in a synthetic medium (SM2). However, none of them showed the same capability in a complex medium such as MRS indicating that the ability to produce 2-butanol is subject to some kind of repression mechanism. Furthermore, by evaluating the performance of the enzymes required to convert meso-2,3-butanediol to 2-butanol, that is, the secondary alcohol dehydrogenase and the diol dehydratase, it was shown that the latter needed the presence of a substrate to be expressed. PMID:25175699

  2. Lactic Acid Bacteria Strains Exert Immunostimulatory Effect on H. pylori-Induced Dendritic Cells.

    PubMed

    Wiese, Ma?gorzata; Eljaszewicz, Andrzej; Helmin-Basa, Anna; Andryszczyk, Marek; Motyl, Ilona; Wieczy?ska, Jolanta; Gackowska, Lidia; Kubiszewska, Izabela; Januszewska, Milena; Micha?kiewicz, Jacek

    2015-01-01

    The aim of this study was to find out if selected lactic acid bacteria (LAB) strains (antagonistic or nonantagonistic against H. pylori in vitro) would differ in their abilities to modulate the DCs maturation profiles reflected by their phenotype and cytokine expression patterns. Methods. Monocyte-derived DCs maturation was elicited by their direct exposure to the LAB strains of L. rhamnosus 900 or L. paracasei 915 (antagonistic and nonantagonistic to H. pylori, resp.), in the presence or absence of H. pylori strain cagA+. The DCs maturation profile was assessed on the basis of surface markers expression and cytokines production. Results. We observed that the LAB strains and the mixtures of LAB with H. pylori are able to induce mature DCs. At the same time, the L. paracasei 915 leads to high IL-10/IL-12p70 cytokine ratio, in contrast to L. rhamnosus 900. Conclusions. This study showed that the analyzed lactobacilli strains are more potent stimulators of DC maturation than H. pylori. Interestingly from the two chosen LAB strains the antagonistic to H. pylori-L. rhamnosus strain 900 has more proinflammatory and probably antibactericidal properties. PMID:25759836

  3. Diversity of lactic acid bacteria during fermentation of a traditional Chinese fish product, Chouguiyu (stinky mandarinfish).

    PubMed

    Dai, Zhiyuan; Li, Yan; Wu, Jiajia; Zhao, Qiaoling

    2013-11-01

    Chouguiyu, or stinky mandarinfish, is a traditional Chinese fermented fish product made of mandarinfish by spontaneous fermentation at the anaerobic condition with low-salt concentration. In order to get a primary understanding of the microbial community presenting in the Chouguiyu fermentation, 61 cultures of lactic acid bacteria (LAB) from various fermentation period were isolated using MRS agar plates and characterized based on a combination of phenotypic and genotypic approaches including amplified ribosomal DNA restriction analysis (ARDRA) and 16S rRNA partial gene sequencing analysis. Eight distinct bacterial species belonging to 6 genera were identified in total. Among them, Lactobacillus sakei was the dominant species (63%) during the fermentation, which exhibited great variety in phenotypic tests but unique genotypic characters. Meanwhile, the other LAB species including Lactococcus (Lc.) garvieae, Lc. lactis, Lc. raffinolactis, Vagococcus sp., Enterococcus hermanniensis, Macrococcus caseolyticus as well as Streptococcus parauberis were also recovered from the different fermentation periods, especially at the initial point of the fermentation. This seems to be the 1st report investigating the LAB composition involved in Chouguiyu fermentation and the data obtained in this study may be valuable for selecting starter culture for Chouguiyu industrial-scale production. PMID:24245896

  4. The use of lactic Acid bacteria as a probiotic in Swine diets.

    PubMed

    Yang, Fengjuan; Hou, Chengli; Zeng, Xiangfang; Qiao, Shiyan

    2015-01-01

    As the resistance of pathogens to antibiotics and the possibility of antibiotic residues in animal products attract increasing attention, the interest in the use of alternatives to in-feed antibiotics has been growing. Recent research with Lactic acid bacteria (LAB) in pigs suggests that LAB provide a potential alternative to antibiotic strategies. LAB include Lactobacillus species, Bifidobacterium spp, Bacillus spp, and some other microbes. LAB can adjust the intestinal environment, inhibit or kill pathogens in the gastrointestinal tract and improve the microbial balance in the intestine, as well as regulate intestinal mucosal immunity and maintain intestinal barrier function, thereby benefiting the health of pigs. The related mechanisms for these effects of LAB may include producing microbicidal substances with effects against gastrointestinal pathogens and other harmful microbes, competing with pathogens for binding sites on the intestinal epithelial cell surface and mucin as well as stimulating the immune system. In this review, the characteristics of LAB and their probiotic effects in newborn piglets, weaned piglets, growing pigs and sows are documented. PMID:25633489

  5. Effect of lactic acid bacteria inoculants on in vitro digestibility of wheat and corn silages.

    PubMed

    Weinberg, Z G; Shatz, O; Chen, Y; Yosef, E; Nikbahat, M; Ben-Ghedalia, D; Miron, J

    2007-10-01

    The aim of the study was to determine the effect of 10 sources of lactic acid bacteria (LAB) on dry matter digestibility (DM-D) and neutral detergent fiber digestibility (NDF-D), in various combinations with starch, in vitro. The soluble starch represented a concentrate feed, whereas silage represented feeding only roughage. The DM-D and NDF-D were determined after 24 and 48 h of incubation to represent effective (24 h) and potential (48 h) digestibility. Addition of LAB was both by direct application of the inoculants to rumen fluid (directly fed microbials) and by the use of preinoculated silages. For each feed combination, tubes without added LAB served as controls. The results indicate that, overall, some LAB inoculants applied at ensiling or added directly to the rumen fluid had the potential to increase the DM-D and NDF-D. The major significant inoculant effect on NDF-D was obtained after 24 h of incubation, whereas the effect after 48 h was mainly nonsignificant. The effective inoculants seemed to minimize the inhibitory effect of the starch on NDF-D within 24 h, perhaps by competition with lactate-producing rumen microorganisms. PMID:17881698

  6. Isolation and identification of microorganisms including lactic acid bacteria and their use in microbial deacidification of wines from domestic vineyards.

    PubMed

    Drozdz, Iwona; Makarewicz, Malgorzata; Tuszy?ski, Tadeusz

    2013-01-01

    The aim of this study was to identify various bacteria isolated from grapes and their wines. Additionally we investigated the capacity of lactic acid bacteria for microbiological deacidification of wines produced in Poland. We have identified Oenococcus oeni, Lactobacillus acidophilus and Lactobacillus delbrueckii. During the microbial deacidification process, we observed decreases of total acidity and increases of volatile acidity, with statistically significant changes noted for O. oeni in Marechal Foch and Seyval Blanc, and for Lb. acidophilus in Frontenac. On the other hand, a statistically significant increase in pH was observed in Marechal Foch and Seyval Blanc following deacidification by O. oeni. PMID:24459842

  7. Characteristics of isolated lactic acid bacteria and their effectiveness to improve stylo (Stylosanthes guianensis Sw.) silage quality at various temperatures.

    PubMed

    Liu, Qinhua; Chen, Mingxia; Zhang, Jianguo; Shi, Shangli; Cai, Yimin

    2012-02-01

    Two lactic acid bacteria (LAB) strains, Pediococcus pentosaceus SC1 and Lactobacillus paraplantarum SC2 isolated from king grass silage, were characterized and their effectiveness to improve the silage fermentation quality of stylo (Stylosanthes guianensis Sw.) was studied. Strain SC1 was able to grow at a high temperature of 45°C, while SC2 did not. SC2 normally grew at a low pH of 4.0, while SC1 could not. These two strains and a commercial inoculant of LAB (L. plantarum, LP) were used as additives to stylo silage preparation at various temperatures (20°C, 30°C and 40°C). All LAB inoculants significantly (P < 0.05) reduced the pH value and ammonia-N content, and increased the ratio of lactic acid to acetic acid and quality score compared with the control. In addition, inoculating LAB strains markedly (P < 0.05) reduced butyric acid content at the temperatures of 30°C and 40°C. Compared to SC2 and LP strains, strain SC1 was the most effective for improving stylo silage quality at 20°C, indicated by the increase in lactic acid, ratio of lactic acid to acetic acid and quality score. At 30°C and 40°C, there were no significant differences among SC1, SC2 and LP treatments in pH values, contents of acetic acid, butyric acid and ammonia-N (P > 0.05). PMID:22339693

  8. Suppression of growth of putrefactive and food poisoning bacteria by lactic acid fermentation of kitchen waste

    Microsoft Academic Search

    Q Wang; K Yamabe; J Narita; M Morishita; Y Ohsumi; K Kusano; Y Shirai; H. I Ogawa

    2001-01-01

    In order to produce lactic acid, from kitchen waste, which is a raw material for biodegradable plastic production, it is necessary to store waste for some days in the system of kitchen waste collection and transportation through disposers and pipes. The changes of counts of viable cells in kitchen waste during storage were observed. In spite of seasonal variations, lactic

  9. Summer community structure of aerobic anoxygenic phototrophic bacteria in the western Arctic Ocean.

    PubMed

    Boeuf, Dominique; Cottrell, Matthew T; Kirchman, David L; Lebaron, Philippe; Jeanthon, Christian

    2013-09-01

    Aerobic anoxygenic phototrophic (AAP) bacteria are found in a range of aquatic and terrestrial environments, potentially playing unique roles in biogeochemical cycles. Although known to occur in the Arctic Ocean, their ecology and the factors that govern their community structure and distribution in this extreme environment are poorly understood. Here, we examined summer AAP abundance and diversity in the North East Pacific and the Arctic Ocean with emphasis on the southern Beaufort Sea. AAP bacteria comprised up to 10 and 14% of the prokaryotic community in the bottom nepheloid layer and surface waters of the Mackenzie plume, respectively. However, relative AAP abundances were low in offshore waters. Environmental pufM clone libraries revealed that AAP bacteria in the Alphaproteobacteria and Betaproteobacteria classes dominated in offshore and in river-influenced surface waters, respectively. The most frequent AAP group was a new uncultivated betaproteobacterial clade whose abundance decreased along the salinity gradient of the Mackenzie plume even though its photosynthetic genes were actively expressed in offshore waters. Our data indicate that AAP bacterial assemblages represented a mixture of freshwater and marine taxa mostly restricted to the Arctic Ocean and highlight the substantial influence of riverine inputs on their distribution in coastal environments. PMID:23560623

  10. Impact of an Aerobic Thermophilic Sequencing Batch Reactor on Antibiotic-Resistant Anaerobic Bacteria in Swine Waste

    Microsoft Academic Search

    Martin R. Chénier; Pierre Juteau

    2009-01-01

    The introduction of antibiotics to animal feed has contributed to the selection of antibiotic-resistant bacteria in concentrated\\u000a animal feeding operations. The aim of this work was to characterize the impact of an aerobic thermophilic biotreatment on\\u000a anaerobic antibiotic-resistant bacteria in swine waste. Despite 162- to 6,166-fold reduction in antibiotic-resistant populations\\u000a enumerated in the swine waste at 25°C and 37°C, resistant

  11. Culturable aerobic and facultative bacteria from the gut of the polyphagic dung beetle Thorectes lusitanicus.

    PubMed

    Hernández, Noemi; Escudero, José A; Millán, Álvaro San; González-Zorn, Bruno; Lobo, Jorge M; Verdú, José R; Suárez, Mónica

    2015-04-01

    Unlike other dung beetles, the Iberian geotrupid, Thorectes lusitanicus, exhibits polyphagous behavior; for example, it is able to eat acorns, fungi, fruits, and carrion in addition to the dung of different mammals. This adaptation to digest a wider diet has physiological and developmental advantages and requires key changes in the composition and diversity of the beetle's gut microbiota. In this study, we isolated aerobic, facultative anaerobic, and aerotolerant microbiota amenable to grow in culture from the gut contents of T. lusitanicus and resolved isolate identity to the species level by sequencing 16S rRNA gene fragments. Using BLAST similarity searches and maximum likelihood phylogenetic analyses, we were able to reveal that the analyzed fraction (culturable, aerobic, facultative anaerobic, and aerotolerant) of beetle gut microbiota is dominated by the phyla Proteobacteria, Firmicutes, and Actinobacteria. Among Proteobacteria, members of the order Enterobacteriales (Gammaproteobacteria) were the most abundant. The main functions associated with the bacteria found in the gut of T. lusitanicus would likely include nitrogen fixation, denitrification, detoxification, and diverse defensive roles against pathogens. PMID:24339348

  12. Ammonium-oxidizing bacteria facilitate aerobic degradation of sulfanilic acid in activated sludge.

    PubMed

    Chen, Gang; Ginige, Maneesha P; Kaksonen, Anna H; Cheng, Ka Yu

    2014-01-01

    Sulfanilic acid (SA) is a toxic sulfonated aromatic amine commonly found in anaerobically treated azo dye contaminated effluents. Aerobic acclimatization of SA-degrading mixed microbial culture could lead to co-enrichment of ammonium-oxidizing bacteria (AOB) because of the concomitant release of ammonium from SA oxidation. To what extent the co-enriched AOB would affect SA oxidation at various ammonium concentrations was unclear. Here, a series of batch kinetic experiments were conducted to evaluate the effect of AOB on aerobic SA degradation in an acclimatized activated sludge culture capable of oxidizing SA and ammonium simultaneously. To account for the effect of AOB on SA degradation, allylthiourea was used to inhibit AOB activity in the culture. The results indicated that specific SA degradation rate of the mixed culture was negatively correlated with the initial ammonium concentration (0-93 mM, R²= 0.99). The presence of AOB accelerated SA degradation by reducing the inhibitory effect of ammonium (? 10 mM). The Haldane substrate inhibition model was used to correlate substrate concentration (SA and ammonium) and oxygen uptake rate. This study revealed, for the first time, that AOB could facilitate SA degradation at high concentration of ammonium (? 10 mM) in an enriched activated sludge culture. PMID:25259503

  13. Diversity of lactic acid bacteria isolated from Brazilian water buffalo mozzarella cheese.

    PubMed

    Silva, Luana Faria; Casella, Tiago; Gomes, Elisangela Soares; Nogueira, Mara Correa Lelles; De Dea Lindner, Juliano; Penna, Ana Lúcia Barretto

    2015-02-01

    The water buffalo mozzarella cheese is a typical Italian cheese which has been introduced in the thriving Brazilian market in the last 10 y, with good acceptance by its consumers. Lactic acid bacteria (LAB) play an important role in the technological and sensory quality of mozzarella cheese. In this study, the aim was to evaluate the diversity of the autochthones viable LAB isolated from water buffalo mozzarella cheese under storage. Samples were collected in 3 independent trials in a dairy industry located in the southeast region of Brazil, on the 28th day of storage, at 4 ºC. The LAB were characterized by Gram staining, catalase test, capacity to assimilate citrate, and production of CO2 from glucose. The diversity of LAB was evaluated by RAPD-PCR (randomly amplified polymorphic DNA-polymerase chain reaction), 16S rRNA gene sequencing, and by Vitek 2 system. Twenty LAB strains were isolated and clustered into 12 different clusters, and identified as Streptococcus thermophilus, Enterococcus faecium, Enterococcus durans, Leuconostoc mesenteroides subsp. mesenteroides, Lactobacillus fermentum, Lactobacillus casei, Lactobacillus delbrueckii subsp. bulgaricus, and Lactobacillus helveticus. Enterococcus species were dominant and citrate-positive. Only the strains of L. mesenteroides subsp. mesenteroides and L. fermentum produced CO2 from glucose and were citrate-positive, while L. casei was only citrate positive. This is the first report which elucidates the LAB diversity involved in Brazilian water buffalo mozzarella cheese. Furthermore, the results show that despite the absence of natural whey cultures as starters in production, the LAB species identified are the ones typically found in mozzarella cheese. PMID:25597646

  14. Regulation of the Activity of Lactate Dehydrogenases from Four Lactic Acid Bacteria*

    PubMed Central

    Feldman-Salit, Anna; Hering, Silvio; Messiha, Hanan L.; Veith, Nadine; Cojocaru, Vlad; Sieg, Antje; Westerhoff, Hans V.; Kreikemeyer, Bernd; Wade, Rebecca C.; Fiedler, Tomas

    2013-01-01

    Despite high similarity in sequence and catalytic properties, the l-lactate dehydrogenases (LDHs) in lactic acid bacteria (LAB) display differences in their regulation that may arise from their adaptation to different habitats. We combined experimental and computational approaches to investigate the effects of fructose 1,6-bisphosphate (FBP), phosphate (Pi), and ionic strength (NaCl concentration) on six LDHs from four LABs studied at pH 6 and pH 7. We found that 1) the extent of activation by FBP (Kact) differs. Lactobacillus plantarum LDH is not regulated by FBP, but the other LDHs are activated with increasing sensitivity in the following order: Enterococcus faecalis LDH2 ? Lactococcus lactis LDH2 < E. faecalis LDH1 < L. lactis LDH1 ? Streptococcus pyogenes LDH. This trend reflects the electrostatic properties in the allosteric binding site of the LDH enzymes. 2) For L. plantarum, S. pyogenes, and E. faecalis, the effects of Pi are distinguishable from the effect of changing ionic strength by adding NaCl. 3) Addition of Pi inhibits E. faecalis LDH2, whereas in the absence of FBP, Pi is an activator of S. pyogenes LDH, E. faecalis LDH1, and L. lactis LDH1 and LDH2 at pH 6. These effects can be interpreted by considering the computed binding affinities of Pi to the catalytic and allosteric binding sites of the enzymes modeled in protonation states corresponding to pH 6 and pH 7. Overall, the results show a subtle interplay among the effects of Pi, FBP, and pH that results in different regulatory effects on the LDHs of different LABs. PMID:23720742

  15. Biodiversity of lactic acid bacteria and yeasts in spontaneously-fermented buckwheat and teff sourdoughs.

    PubMed

    Moroni, Alice V; Arendt, Elke K; Dal Bello, Fabio

    2011-05-01

    In this study, four different laboratory scale gluten-free (GF) sourdoughs were developed from buckwheat or teff flours. The fermentations were initiated by the spontaneous biota of the flours and developed under two technological conditions (A and B). Sourdoughs were propagated by continuous back-slopping until the stability was reached. The composition of the stable biota occurring in each sourdough was assessed using both culture-dependent and -independent techniques. Overall, a broad spectrum of lactic acid bacteria (LAB) and yeasts species, belonging mainly to the genera Lactobacillus, Pediococcus, Leuconostoc, Kazachstania and Candida, were identified in the stable sourdoughs. Buckwheat and teff sourdoughs were dominated mainly by obligate or facultative heterofermentative LAB, which are commonly associated with traditional wheat or rye sourdoughs. However, the spontaneous fermentation of the GF flours resulted also in the selection of species which are not consider endemic to traditional sourdoughs, i.e. Pediococcus pentosaceus, Leuconostoc holzapfelii, Lactobacillus gallinarum, Lactobacillus vaginalis, Lactobacillus sakei, Lactobacillus graminis and Weissella cibaria. In general, the composition of the stable biota was strongly affected by the fermentation conditions, whilst Lactobacillus plantarum dominated in all buckwheat sourdoughs. Lactobacillus pontis is described for the first time as dominant species in teff sourdough. Among yeasts, Saccharomyces cerevisiae and Candida glabrata dominated teff sourdoughs, whereas the solely Kazachstania barnetti was isolated in buckwheat sourdough developed under condition A. This study allowed the identification and isolation of LAB and yeasts species which are highly competitive during fermentation of buckwheat or teff flours. Representatives of these species can be selected as starters for the production of sourdough destined to GF bread production. PMID:21356457

  16. Core Fluxome and Metafluxome of Lactic Acid Bacteria under Simulated Cocoa Pulp Fermentation Conditions

    PubMed Central

    Adler, Philipp; Bolten, Christoph Josef; Dohnt, Katrin; Hansen, Carl Erik

    2013-01-01

    In the present work, simulated cocoa fermentation was investigated at the level of metabolic pathway fluxes (fluxome) of lactic acid bacteria (LAB), which are typically found in the microbial consortium known to convert nutrients from the cocoa pulp into organic acids. A comprehensive 13C labeling approach allowed to quantify carbon fluxes during simulated cocoa fermentation by (i) parallel 13C studies with [13C6]glucose, [1,2-13C2]glucose, and [13C6]fructose, respectively, (ii) gas chromatography-mass spectrometry (GC/MS) analysis of secreted acetate and lactate, (iii) stoichiometric profiling, and (iv) isotopomer modeling for flux calculation. The study of several strains of L. fermentum and L. plantarum revealed major differences in their fluxes. The L. fermentum strains channeled only a small amount (4 to 6%) of fructose into central metabolism, i.e., the phosphoketolase pathway, whereas only L. fermentum NCC 575 used fructose to form mannitol. In contrast, L. plantarum strains exhibited a high glycolytic flux. All strains differed in acetate flux, which originated from fractions of citrate (25 to 80%) and corresponding amounts of glucose and fructose. Subsequent, metafluxome studies with consortia of different L. fermentum and L. plantarum strains indicated a dominant (96%) contribution of L. fermentum NCC 575 to the overall flux in the microbial community, a scenario that was not observed for the other strains. This highlights the idea that individual LAB strains vary in their metabolic contribution to the overall fermentation process and opens up new routes toward streamlined starter cultures. L. fermentum NCC 575 might be one candidate due to its superior performance in flux activity. PMID:23851099

  17. Synthesis of ?-Aminobutyric Acid by Lactic Acid Bacteria Isolated from a Variety of Italian Cheeses?

    PubMed Central

    Siragusa, S.; De Angelis, M.; Di Cagno, R.; Rizzello, C. G.; Coda, R.; Gobbetti, M.

    2007-01-01

    The concentrations of ?-aminobutyric acid (GABA) in 22 Italian cheese varieties that differ in several technological traits markedly varied from 0.26 to 391 mg kg?1. Presumptive lactic acid bacteria were isolated from each cheese variety (total of 440 isolates) and screened for the capacity to synthesize GABA. Only 61 isolates showed this activity and were identified by partial sequencing of the 16S rRNA gene. Twelve species were found. Lactobacillus paracasei PF6, Lactobacillus delbrueckii subsp. bulgaricus PR1, Lactococcus lactis PU1, Lactobacillus plantarum C48, and Lactobacillus brevis PM17 were the best GABA-producing strains during fermentation of reconstituted skimmed milk. Except for L. plantarum C48, all these strains were isolated from cheeses with the highest concentrations of GABA. A core fragment of glutamate decarboxylase (GAD) DNA was isolated from L. paracasei PF6, L. delbrueckii subsp. bulgaricus PR1, L. lactis PU1, and L. plantarum C48 by using primers based on two highly conserved regions of GAD. A PCR product of ca. 540 bp was found for all the strains. The amino acid sequences deduced from nucleotide sequence analysis showed 98, 99, 90, and 85% identity to GadB of L. plantarum WCFS1 for L. paracasei PF6, L. delbrueckii subsp. bulgaricus PR1, L. lactis PU1, and L. plantarum C48, respectively. Except for L. lactis PU1, the three lactobacillus strains survived and synthesized GABA under simulated gastrointestinal conditions. The findings of this study provide a potential basis for exploiting selected cheese-related lactobacilli to develop health-promoting dairy products enriched in GABA. PMID:17890341

  18. Distribution of antimicrobial-resistant lactic acid bacteria in natural cheese in Japan.

    PubMed

    Ishihara, Kanako; Nakajima, Kumiko; Kishimoto, Satoko; Atarashi, Fumiaki; Muramatsu, Yasukazu; Hotta, Akitoyo; Ishii, Satomi; Takeda, Yasuyuki; Kikuchi, Masanori; Tamura, Yutaka

    2013-10-01

    To determine and compare the extent of contamination caused by antimicrobial-resistant lactic acid bacteria (LAB) in imported and domestic natural cheeses on the Japanese market, LAB were isolated using deMan, Rogosa and Sharpe (MRS) agar and MRS agar supplemented with six antimicrobials. From 38 imported and 24 Japanese cheeses, 409 LAB isolates were obtained and their antimicrobial resistance was tested. The percentage of LAB resistant to dihydrostreptomycin, erythromycin, and/or oxytetracycline isolated from imported cheeses (42.1%) was significantly higher than that of LAB resistant to dihydrostreptomycin or oxytetracycline from cheeses produced in Japan (16.7%; P=0.04). Antimicrobial resistance genes were detected in Enterococcus faecalis (tetL, tetM, and ermB; tetL and ermB; tetM) E. faecium (tetM), Lactococcus lactis (tetS), Lactobacillus (Lb.), casei/paracasei (tetM or tetW), and Lb. rhamnosus (ermB) isolated from seven imported cheeses. Moreover, these E. faecalis isolates were able to transfer antimicrobial resistance gene(s). Although antimicrobial resistance genes were not detected in any LAB isolates from Japanese cheeses, Lb. casei/paracasei and Lb. coryniformis isolates from a Japanese farm-made cheese were resistant to oxytetracycline (minimal inhibitory concentration [MIC], 32?µg/mL). Leuconostoc isolates from three Japanese farm-made cheeses were also resistant to dihydrostreptomycin (MIC, 32 to?>512?µg/mL). In conclusion, the present study demonstrated contamination with antimicrobial-resistant LAB in imported and Japanese farm-made cheeses on the Japanese market, but not in Japanese commercial cheeses. PMID:23930694

  19. Phenotypic and Genotypic Characterization of Non-Starter Lactic Acid Bacteria in Mature Cheddar Cheese

    PubMed Central

    Fitzsimons, N. A.; Cogan, T. M.; Condon, S.; Beresford, T.

    1999-01-01

    Non-starter lactic acid bacteria were isolated from 14 premium-quality and 3 sensorially defective mature Irish Cheddar cheeses, obtained from six manufacturers. From countable plates of Lactobacillus-selective agar, 20 single isolated colonies were randomly picked per cheese. All 331 viable isolates were biochemically characterized as mesophilic (i.e., group II) Lactobacillus spp. Phenotypically, the isolates comprised 96.4% L. paracasei, 2.1% L. plantarum, 0.3% L. curvatus, 0.3% L. brevis, and 0.9% unidentified species. Randomly amplified polymorphic DNA (RAPD) analysis was used to rapidly identify the dominant strain groups in nine cheeses from three of the factories, and through clustering by the unweighted pair group method with arithmetic averages, an average of seven strains were found per cheese. In general, strains isolated from cheese produced at the same factory clustered together. The majority of isolates associated with premium-quality cheese grouped together and apart from clusters of strains from defective-quality cheese. No correlation was found between the isomer of lactate produced and RAPD profiles, although isolates which did not ferment ribose clustered together. The phenotypic and genotypic methods employed were validated with a selection of 31 type and reference strains of mesophilic Lactobacillus spp. commonly found in Cheddar cheese. RAPD analysis was found to be a useful and rapid method for identifying isolates to the species level. The low homology exhibited between RAPD banding profiles for cheese isolates and collection strains demonstrated the heterogeneity of the L. paracasei complex. PMID:10427029

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

    PubMed Central

    2010-01-01

    Background Constipation is a significant problem in the elderly, specifically nursing home and/or extended-care facility residents are reported to suffer from constipation. Lactic acid bacteria (LAB) are beneficial probiotic organisms that contribute to improved nutrition, microbial balance, and immuno-enhancement of the intestinal tract, as well as diarrhea and constipation effect. The objective of this study was to investigate the efficacy of this LAB supplement in the management of nursing home residents. Methods Nineteen subjects (8M, 11F; mean age 77.1 ± 10.1) suffering with chronic constipation were assigned to receive LAB (3.0 × 1011 CFU/g) twice (to be taken 30 minutes after breakfast and dinner) a day for 2 weeks in November 2008. Subjects draw up a questionnaire on defecation habits (frequency of defecation, amount and state of stool), and we collected fecal samples from the subjects both before entering and after ending the trial, to investigate LAB levels and inhibition of harmful enzyme activities. Results were tested with SAS and Student's t-test. Results Analysis of questionnaire showed that there was an increase in the frequency of defecation and amount of stool excreted in defecation habit after LAB treatment, but there were no significant changes. And it also affects the intestinal environment, through significantly increase (p < 0.05) fecal LAB levels. In addition, tryptophanase and urease among harmful enzyme activities of intestinal microflora were significantly decreased (p < 0.05) after LAB treatment. Conclusion LAB, when added to the standard treatment regimen for nursing home residents with chronic constipation, increased defecation habit such as frequency of defecation, amount and state of stool. So, it may be used as functional probiotics to improve human health by helping to prevent constipation. PMID:20137076

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

    PubMed Central

    Boonaert, Christophe J. P.; Rouxhet, Paul G.

    2000-01-01

    The surface chemical composition and physicochemical properties (hydrophobicity and zeta potential) of two lactic acid bacteria, Lactococcus lactis subsp. lactis bv. diacetilactis and Lactobacillus helveticus, have been investigated using cells harvested in exponential or stationary growth phase. The surface composition determined by X-ray photoelectron spectroscopy (XPS) was converted into a molecular composition in terms of proteins, polysaccharides, and hydrocarbonlike compounds. The concentration of the last was always below 15% (wt/wt), which is related to the hydrophilic character revealed by water contact angles of less than 30°. The surfaces of L. lactis cells had a polysaccharide concentration about twice that of proteins. The S-layer of L. helveticus was either interrupted or crossed by polysaccharide-rich compounds; the concentration of the latter was higher in the stationary growth phase than in the exponential growth phase. Further progress was made in the interpretation of XPS data in terms of chemical functions by showing that the oxygen component at 531.2 eV contains a contribution of phosphate in addition to the main contribution of the peptide link. The isoelectric points were around 2 and 3, and the electrophoretic mobilities above pH 5 (ionic strength, 1 mM) were about ?3.0 × 10?8 and ?0.6 × 10?8 m2 s?1 V?1 for L. lactis and L. helveticus, respectively. The electrokinetic properties of the latter reveal the influence of carboxyl groups, while the difference between the two strains is related to a difference between N/P surface concentration ratios, reflecting the relative exposure of proteins and phosphate groups at the surface. PMID:10831437

  2. Decolorization of molasses melanoidins and palm oil mill effluent phenolic compounds by fermentative lactic acid bacteria.

    PubMed

    Limkhuansuwan, Vassanasak; Chaiprasert, Pawinee

    2010-01-01

    Lactobacillus plantarum SF5.6 is one of the lactic acid bacteria (LAB) that has the highest ability of molasses melanoidin (MM) decolorization among the 2114 strains of LAB. The strains were isolated from spoilage, pickle fruit and vegetable, soil and sludge from the wastewater treatment system by using technical step of enrichment, primary screening and secondary screening. This LAB strain SF5.6 was identified by 16S rDNA analysis and carbohydrate fermentation (API 50 CH). The top five LAB strains having high MM decolorization (> 55%), namely TBSF5.8-1, TBSF2.1-1, TBSF2.1, FF4A and SF5.6 were selected to determine the optimal condition. It was found that the temperature at 30 degrees C under facultative conditions in GPY-MM medium (0.5% glucose, 0.1% peptone, 0.1% yeast extract, 0.1% sodium acetate, 0.05% MgSO4 and 0.005% MnCl2 in MM solution at pH 6) giving a high microbial growth and MM decolorization for all five strains. It was noticed that the decolorization of MM by LAB strains might be cell growth associated. L. plantarum SF5.6 grew rapidly within one day while the other strains took 2-3 days. This L. plantarum SF5.6 could rapidly decolorize MM to 60.91% without any lag phase, and it also had the ability to remove 34.00% phenolic compounds and 15.88% color from treated palm oil mill effluent. PMID:21179960

  3. Construction and use of a computerized DNA fingerprint database for lactic acid bacteria from silage.

    PubMed

    Chan, Russell K; Wortman, Cora R; Smiley, Brenda K; Hendrick, Carol A

    2003-12-01

    Efficient selection of new silage inoculant strains from a collection of over 10,000 isolates of lactic acid bacteria (LAB) requires excellent strain discrimination. Toward that end, we constructed a GelCompar II database of DNA fingerprint patterns of ethidium bromide-stained EcoRI fragments of total LAB DNA separated by conventional agarose gel electrophoresis. We found that the total DNA patterns were strain-specific; 56/60 American Type Culture Collection strains of 33 species of LAB could be distinguished. Enterococcus faecium strains ATCC19434 and ATCC35667 had identical total DNA patterns and RiboPrints. Lactobacillus rhamnosus strains ATCC7469 and ATCC27773 also had identical total DNA patterns, but different RiboPrints. EcoRI RiboPrint patterns could distinguish only about 9/23 Lactobacillus plantarum strains and about 6/10 Lactobacillus buchneri strains, whereas all 33 strains could be distinguished by EcoRI total DNA patterns. Despite gel-to-gel variation, new DNA patterns can be readily grouped with existing patterns using GelCompar II. The database contains large homogenous clusters of L. plantarum, E. faecium, L. buchneri, Lactobacillus brevis and Pediococcus species that can be used for tentative taxonomic assignment. We routinely use the DNA fingerprint database to identify and characterize new strains, eliminate duplicate isolates and for quality control of inoculant product strains. The GelCompar II database has been in continuous use for 7 years and contains more than 3600 patterns representing approximately 700 unique patterns from over 300 gels and is the largest computerized DNA fingerprint database for LAB yet reported. PMID:14607400

  4. Competitive inhibition of Listeria monocytogenes in ready-to-eat meat products by lactic acid bacteria.

    PubMed

    Amézquita, A; Brashears, M M

    2002-02-01

    Forty-nine strains of lactic acid bacteria (LAB), isolated from commercially available ready-to-eat (RTE) meat products, were screened for their ability to inhibit the growth of Listeria monocytogenes at refrigeration (5 degrees C) temperatures on agar spot tests. The three most inhibitory strains were identified as Pediococcus acidilactici, Lactobacillus casei, and Lactobacillus paracasei by 16S rDNA sequence analysis. Their antilisterial activity was quantified in associative cultures in deMan Rogosa Sharpe (MRS) broth at 5 degrees C for 28 days, resulting in a pathogen reduction of 3.5 log10 cycles compared to its initial level. A combined culture of these strains was added to frankfurters and cooked ham coinoculated with L. monocytogenes, vacuum packaged, and stored at 5 degrees C for 28 days. Bacteriostatic activity was observed in cooked ham, whereas bactericidal activity was observed in frankfurters. Numbers of L. monocytogenes were 4.2 to 4.7 log10 and 2.6 log10 cycles lower than controls in frankfurters and cooked ham, respectively, after the 28-day refrigerated storage. In all cases, numbers of LAB increased by only 1 log10 cycle. The strain identified as P. acidilactici was possibly a bacteriocin producer, whereas the antilisterial activity of the other two strains was due to the production of organic acids. There was no significant difference (P > 0.05) in the antilisterial activity detected in frankfurters whether the LAB strains were used individually or as combined cultures. Further studies over a 56-day period indicated no impact on the quality of the product. This method represents a potential antilisterial intervention in RTE meats, because it inhibited the growth of the pathogen at refrigeration temperatures without causing sensory changes. PMID:11848562

  5. Comparison between rinse and crush-and-rub sampling for aerobic bacteria recovery from broiler hatching eggs after sanitization

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study compared surface and deep eggshell aerobic bacteria recovered by rinse and crush-and-rub sampling methods for commercial hatching eggs after treatment with sanitizers. Eggs were arranged into 5 treatments consisting of No-treatment, Water, and three sanitizers. Sanitizers were Hydrogen ...

  6. Comparison between Rinse and Crush-and-Rub Sampling for Aerobic Bacteria Recovery from Hatching Eggs after Sanitization

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study compared surface and deep eggshell aerobic bacteria recovered by rinse and crush-and-rub sampling methods for commercial hatching eggs after treatments with sanitizers. Eggs were arranged into 5 treatments consisting of three sanitizers, Water, and No-treatment. Sanitizers were Hydrogen...

  7. Cultivable microbiota of Lithobates catesbeianus and advances in the selection of lactic acid bacteria as biological control agents in raniculture.

    PubMed

    Mendoza, Gabriela Montel; Pasteris, Sergio E; Ale, Cesar E; Otero, María C; Bühler, Marta I; Nader-Macías, María E Fátima

    2012-12-01

    The cultivable microbiota of skin and cloaca of captive Lithobates catesbeianus includes microorganisms generally accepted as beneficial and potentially pathogenic bacteria. In order to select a group of potentially probiotic bacteria, 136 isolates were evaluated for their surface properties and production of antagonistic metabolites. Then, 11 lactic acid bacteria (LAB) strains were selected and identified as Lactobacillus plantarum, Lb. brevis, Pediococcus pentosaceus, Lactococcus lactis, L. garvieae and Enterococcus gallinarum. Studies of compatibility indicate that all the strains could be included in a multi-strain probiotic, with the exception of Ent. gallinarum CRL 1826 which inhibited LAB species through a bacteriocin-like metabolite. These results contribute to the design of a probiotic product to improve the sanitary status of bullfrogs in intensive culture systems, to avoid the use of antibiotics and thus to reduce production costs. It could also be an alternative to prevent infectious diseases during the ex situ breeding of amphibian species under threat of extinction. PMID:22695175

  8. Growth of Aerobic Ripening Bacteria at the Cheese Surface Is Limited by the Availability of Iron

    PubMed Central

    Back, Alexandre; Irlinger, Françoise

    2012-01-01

    The microflora on the surface of smear-ripened cheeses is composed of various species of bacteria and yeasts that contribute to the production of the desired organoleptic properties. The objective of the present study was to show that iron availability is a limiting factor in the growth of typical aerobic ripening bacteria in cheese. For that purpose, we investigated the effect of iron or siderophore addition in model cheeses that were coinoculated with a yeast and a ripening bacterium. Both iron and the siderophore desferrioxamine B stimulated the growth of ripening bacteria belonging to the genera Arthrobacter, Corynebacterium, and Brevibacterium. The extent of stimulation was strain dependent, and generally, the effect of desferrioxamine B was greater than that of iron. Measurements of the expression of genes related to the metabolism of iron by Arthrobacter arilaitensis Re117 by real-time reverse transcription-PCR showed that these genes were transcribed during growth in cheese. The addition of desferrioxamine B increased the expression of two genes encoding iron-siderophore ABC transport binding proteins. The addition of iron decreased the expression of siderophore biosynthesis genes and of part of the genes encoding iron-siderophore ABC transport components. It was concluded that iron availability is a limiting factor in the growth of typical cheese surface bacteria. The selection of strains with efficient iron acquisition systems may be useful for the development of defined-strain surface cultures. Furthermore, the importance of iron metabolism in the microbial ecology of cheeses should be investigated since it may result in positive or negative microbial interactions. PMID:22367081

  9. The effect of addition of lactic acid bacteria inoculum to wheat and corn silages in Israel

    E-print Network

    Boyer, Edmond

    fermentation in which lactic acid is produced under anaerobic con- ditions, and as a result the pH decreases stage is during the first week of fermentation, when oxygen is still present and plant respiration

  10. Phenotypic and molecular identification and clustering of lactic acid bacteria and yeasts from wheat (species Triticum durum and Triticum aestivum) sourdoughs of Southern Italy.

    PubMed

    Corsetti, A; Lavermicocca, P; Morea, M; Baruzzi, F; Tosti, N; Gobbetti, M

    2001-02-28

    The microflora of 25 wheat sourdoughs from the Apulia region, Southern Italy, was characterized. The sourdoughs were mainly produced from Triticum durum wheat. The number of lactic acid bacteria and yeasts ranged from ca. log 7.5 to log 9.3 colony forming units (cfu)/g and from log 5.5 to log 8.4 cfu/g, respectively. About 38% of the 317 isolates of lactic acid bacteria were identified by conventional physiological and biochemical tests. Phenotypic identification was confirmed by 16S rDNA and 16S/23S rRNA spacer region PCR. Overall, 30% of the isolates were identified as Lactobacillus sanfranciscensis, 20% as Lb. alimentarius, 14% as Lb. brevis, 12% as Leuconostoc citreum, 7% as Lb. plantarum, 6% as Lactococcus lactis subsp. lactis, 4% as Lb. fermentum and Lb. acidophilus, 2% as Weissella confusa and 1% as Lb. delbrueckii subsp. delbrueckii. Some of these species have not been previously isolated from sourdoughs. Since bakers yeast is widely used in sourdough production, Saccharomyces cerevisiae was largely found. The phenotypical relationships within the main lactic acid bacteria identified were established by using cluster analysis. A microbial map of the 25 sourdoughs was plotted showing characteristic associations among lactic acid bacteria and differences in the lactic acid bacteria species which were mainly due to the species of wheat flour, use of bakers yeast and type of bread. PMID:11252516

  11. Acetic acid production from food wastes using yeast and acetic acid bacteria micro-aerobic fermentation.

    PubMed

    Li, Yang; He, Dongwei; Niu, Dongjie; Zhao, Youcai

    2015-05-01

    In this study, yeast and acetic acid bacteria strains were adopted to enhance the ethanol-type fermentation resulting to a volatile fatty acids yield of 30.22 g/L, and improve acetic acid production to 25.88 g/L, with food wastes as substrate. In contrast, only 12.81 g/L acetic acid can be obtained in the absence of strains. The parameters such as pH, oxidation reduction potential and volatile fatty acids were tested and the microbial diversity of different strains and activity of hydrolytic ferment were investigated to reveal the mechanism. The optimum pH and oxidation reduction potential for the acetic acid production were determined to be at 3.0-3.5 and -500 mV, respectively. Yeast can convert organic matters into ethanol, which is used by acetic acid bacteria to convert the organic wastes into acetic acid. The acetic acid thus obtained from food wastes micro-aerobic fermentation liquid could be extracted by distillation to get high-pure acetic acid. PMID:25416587

  12. Hydroxycinnamic acids used as external acceptors of electrons: an energetic advantage for strictly heterofermentative lactic acid bacteria.

    PubMed

    Filannino, Pasquale; Gobbetti, Marco; De Angelis, Maria; Di Cagno, Raffaella

    2014-12-01

    The metabolism of hydroxycinnamic acids by strictly heterofermentative lactic acid bacteria (19 strains) was investigated as a potential alternative energy route. Lactobacillus curvatus PE5 was the most tolerant to hydroxycinnamic acids, followed by strains of Weissella spp., Lactobacillus brevis, Lactobacillus fermentum, and Leuconostoc mesenteroides, for which the MIC values were the same. The highest sensitivity was found for Lactobacillus rossiae strains. During growth in MRS broth, lactic acid bacteria reduced caffeic, p-coumaric, and ferulic acids into dihydrocaffeic, phloretic, and dihydroferulic acids, respectively, or decarboxylated hydroxycinnamic acids into the corresponding vinyl derivatives and then reduced the latter compounds to ethyl compounds. Reductase activities mainly emerged, and the activities of selected strains were further investigated in chemically defined basal medium (CDM) under anaerobic conditions. The end products of carbon metabolism were quantified, as were the levels of intracellular ATP and the NAD(+)/NADH ratio. Electron and carbon balances and theoretical ATP/glucose yields were also estimated. When CDM was supplemented with hydroxycinnamic acids, the synthesis of ethanol decreased and the concentration of acetic acid increased. The levels of these metabolites reflected on the alcohol dehydrogenase and acetate kinase activities. Overall, some biochemical traits distinguished the common metabolism of strictly heterofermentative strains: main reductase activity toward hydroxycinnamic acids, a shift from alcohol dehydrogenase to acetate kinase activities, an increase in the NAD(+)/NADH ratio, and the accumulation of supplementary intracellular ATP. Taken together, the above-described metabolic responses suggest that strictly heterofermentative lactic acid bacteria mainly use hydroxycinnamic acids as external acceptors of electrons. PMID:25261518

  13. Aerobic and facultatively anaerobic bacteria associated with the gut of Canada geese (Branta canadensis) and whistling swans (Cygnus columbianus columbianus).

    PubMed

    Damaré, J M; Hussong, D; Weiner, R M; Colwell, R R

    1979-08-01

    Aerobic and facultatively anaerobic bacteria from the intestinal tracts of swans and geese were isolated and characterized as part of a larger study of the microbiological effects of migratory waterfowl on water quality. A total of 356 isolates were identified by using rapid identification methods and classified by using numerical taxonomy. A diverse population of bacteria was recovered from the waterfowl, and representative strains could be classified into 21 phena. The majority of the aerobic, heterotrophic bacteria found in the gut of the waterfowl were species of Enterobacteriaceae. Streptococcus. Lactobacillus, and Bacillus. Unfortunately, the birds that were examined did not harbor significant numbers of any waterfowl-specific bacterial species. Thus, it may not be possible to assess microbiological impact of migratory waterfowl by using and "indicator" species since avian fecal pollution could not be distinguished from animal and human fecal pollution. PMID:518085

  14. Aerobic and facultatively anaerobic bacteria associated with the gut of Canada geese (Branta canadensis) and whistling swans (Cygnus columbianus columbianus).

    PubMed Central

    Damaré, J M; Hussong, D; Weiner, R M; Colwell, R R

    1979-01-01

    Aerobic and facultatively anaerobic bacteria from the intestinal tracts of swans and geese were isolated and characterized as part of a larger study of the microbiological effects of migratory waterfowl on water quality. A total of 356 isolates were identified by using rapid identification methods and classified by using numerical taxonomy. A diverse population of bacteria was recovered from the waterfowl, and representative strains could be classified into 21 phena. The majority of the aerobic, heterotrophic bacteria found in the gut of the waterfowl were species of Enterobacteriaceae. Streptococcus. Lactobacillus, and Bacillus. Unfortunately, the birds that were examined did not harbor significant numbers of any waterfowl-specific bacterial species. Thus, it may not be possible to assess microbiological impact of migratory waterfowl by using and "indicator" species since avian fecal pollution could not be distinguished from animal and human fecal pollution. PMID:518085

  15. Antimould activity of sourdough lactic acid bacteria: identification of a mixture of organic acids produced by Lactobacillus sanfrancisco CB1.

    PubMed

    Corsetti, A; Gobbetti, M; Rossi, J; Damiani, P

    1998-08-01

    Sourdough lactic acid bacteria, cultivated in wheat flour hydrolysate, produced antimould compounds. The antimould activity varied greatly among the strains and was mainly detected within obligately heterofermentative Lactobacillus spp. Among these, Lb. sanfrancisco CB1 had the largest spectrum. It inhibited moulds related to bread spoilage such as Fusarium, Penicillium, Aspergillus and Monilia. A mixture of acetic, caproic, formic, propionic, butyric and n-valeric acids, acting in a synergistic way, was responsible for the antimould activity. Caproic acid played a key role in inhibiting mould growth. PMID:9763693

  16. Rapid High-Throughput Assessment of Aerobic Bacteria in Complex Samples by Fluorescence-Based Oxygen Respirometry

    PubMed Central

    O'Mahony, Fiach C.; Papkovsky, Dmitri B.

    2006-01-01

    A simple method has been developed for the analysis of aerobic bacteria in complex samples such as broth and food homogenates. It employs commercial phosphorescent oxygen-sensitive probes to monitor oxygen consumption of samples containing bacteria using standard microtiter plates and fluorescence plate readers. As bacteria grow in aqueous medium, at certain points they begin to deplete dissolved oxygen, which is seen as an increase in probe fluorescence above baseline signal. The time required to reach threshold signal is used to either enumerate bacteria based on a predetermined calibration or to assess the effects of various effectors on the growth of test bacteria by comparison with an untreated control. This method allows for the sensitive (down to a single cell), rapid (0.5 to 12 h) enumeration of aerobic bacteria without the need to conduct lengthy (48 to 72 h) and tedious colony counts on agar plates. It also allows for screening a wide range of chemical and environmental samples for their toxicity. These assays have been validated with different bacteria, including Escherichia coli, Micrococcus luteus, and Pseudomonas fluorescens, with the enumeration of total viable counts in broth and industrial food samples (packaged ham, chicken, and mince meat), and comparison with established agar plating and optical-density-at-600-nm assays has been given. PMID:16461677

  17. Plutonium Oxidation State Distribution under Aerobic and Anaerobic Subsurface Conditions for Metal-Reducing Bacteria

    NASA Astrophysics Data System (ADS)

    Reed, D. T.; Swanson, J.; Khaing, H.; Deo, R.; Rittmann, B.

    2009-12-01

    The fate and potential mobility of plutonium in the subsurface is receiving increased attention as the DOE looks to cleanup the many legacy nuclear waste sites and associated subsurface contamination. Plutonium is the near-surface contaminant of concern at several DOE sites and continues to be the contaminant of concern for the permanent disposal of nuclear waste. The mobility of plutonium is highly dependent on its redox distribution at its contamination source and along its potential migration pathways. This redox distribution is often controlled, especially in the near-surface where organic/inorganic contaminants often coexist, by the direct and indirect effects of microbial activity. The redox distribution of plutonium in the presence of facultative metal reducing bacteria (specifically Shewanella and Geobacter species) was established in a concurrent experimental and modeling study under aerobic and anaerobic conditions. Pu(VI), although relatively soluble under oxidizing conditions at near-neutral pH, does not persist under a wide range of the oxic and anoxic conditions investigated in microbiologically active systems. Pu(V) complexes, which exhibit high chemical toxicity towards microorganisms, are relatively stable under oxic conditions but are reduced by metal reducing bacteria under anaerobic conditions. These facultative metal-reducing bacteria led to the rapid reduction of higher valent plutonium to form Pu(III/IV) species depending on nature of the starting plutonium species and chelating agents present in solution. Redox cycling of these lower oxidation states is likely a critical step in the formation of pseudo colloids that may lead to long-range subsurface transport. The CCBATCH biogeochemical model is used to explain the redox mechanisms and final speciation of the plutonium oxidation state distributions observed. These results for microbiologically active systems are interpreted in the context of their importance in defining the overall migration of plutonium in the subsurface.

  18. Probiotic potential of lactic acid bacteria present in home made curd in southern India

    PubMed Central

    Balamurugan, Ramadass; Chandragunasekaran, Aarthi Sophia; Chellappan, Gowri; Rajaram, Krithika; Ramamoorthi, Gayathri; Ramakrishna, Balakrishnan S.

    2014-01-01

    Background & objectives: The human gut microbiota play a significant role in nutritional processes. The concept of probiotics has led to widespread consumption of food preparations containing probiotic microbes such as curd and yogurt. Curd prepared at home is consumed every day in most homes in southern India. In this study the home-made curd was evaluated for lactic acid bacteria (LAB) with probiotic potential. Methods: Fifteen LAB (12 lactobacilli, 1 Lactococcus, 2 Leuconostoc) and one yeast isolated from home-made curd were evaluated for resistance to acid, pepsin, pancreatin and bile salts; antimicrobial resistance; intrinsic antimicrobial activity; adherence to Caco-2 epithelial cells; ability to block pathogen adherence to Caco-2 cells; ability to inhibit interleukin (IL)-8 secretion from HT-29 epithelial cells in response to Vibrio cholerae; and ability to induce anti-inflammatory cytokine expression in THP-1 monocyte cells. Results: Lactobacillus abundance in fermenting curd peaked sharply at 12 h. Nine of the strains survived exposure to acid (pH 3.0) for at least one hour, and all strains survived in the presence of pancreatin or bile salts for 3 h. None showed haemolytic activity. All were resistant to most antimicrobials tested, but were sensitive to imipenem. Most strains inhibited the growth of Salmonella Typhimurium while five inhibited growth of V. cholerae O139. Seven strains showed adherence to Caco-2 cells ranging from 20-104 per cent of adherence of an adherent strain of Escherichia coli, but all inhibited V. cholerae adherence to Caco-2 cells by 20-100 per cent. They inhibited interleukin-8 secretion from HT-29 cells, in response to V. cholerae, by 50-80 per cent. Two strains induced IL-10 and IL-12 messenger ribonucleic acid (mRNA) expression in THP-1 cells. Interpretation & conclusions: LAB in curd had properties consistent with probiotic potential, but these were not consistent across species. LAB abundance in curd increased rapidly at 12 h of fermentation at room temperature and declined thereafter. PMID:25366201

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

    PubMed

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

    2014-11-01

    Ethiopian injera, a soft pancake, baked from fermented batter, is preferentially prepared from tef (Eragrostis tef) flour. The phytic acid (PA) content of tef is high and is only partly degraded during the fermentation step. PA chelates with iron and zinc in the human digestive tract and strongly inhibits their absorption. With the aim to formulate a starter culture that would substantially degrade PA during injera preparation, we assessed the potential of microorganisms isolated from Ethiopian household-tef fermentations to degrade PA. Lactic acid bacteria (LAB) were found to be among the dominating microorganisms. Seventy-six isolates from thirteen different tef fermentations were analyzed for phytase activity and thirteen different isolates of seven different species were detected to be positive in a phytase screening assay. In 20-mL model tef fermentations, out of these thirteen isolates, the use of Lactobacillus (L.) buchneri strain MF58 and Pediococcus pentosaceus strain MF35 resulted in lowest PA contents in the fermented tef of 41% and 42%, respectively of its initial content. In comparison 59% of PA remained when spontaneously fermented. Full scale tef fermentation (0.6L) and injera production using L. buchneri MF58 as culture additive decreased PA in cooked injera from 1.05 to 0.34±0.02 g/100 g, representing a degradation of 68% compared to 42% in injera from non-inoculated traditional fermentation. The visual appearance of the pancakes was similar. The final molar ratios of PA to iron of 4 and to zinc of 12 achieved with L. buchneri MF58 were decreased by ca. 50% compared to the traditional fermentation. In conclusion, selected LAB strains in tef fermentations can degrade PA, with L. buchneri MF58 displaying the highest PA degrading potential. The 68% PA degradation achieved by the application of L. buchneri MF58 would be expected to improve human zinc absorption from tef-injera, but further PA degradation is probably necessary if iron absorption has to be increased. PMID:25180667

  20. Enrichment of ACE inhibitory peptides in navy bean (Phaseolus vulgaris) using lactic acid bacteria.

    PubMed

    Rui, Xin; Wen, Delan; Li, Wei; Chen, Xiaohong; Jiang, Mei; Dong, Mingsheng

    2015-02-11

    The present study was conducted to explore a novel strategy to enhance angiotensin I-converting enzyme (ACE) inhibitory activities of navy bean by preparation of navy bean milk (NBM) which was then subjected to fermentation of four lactic acid bacteria (LAB) strains, namely, Lactobacillus bulgaricus, Lactobacillus helveticus MB2-1, Lactobacillus plantarum B1-6, and Lactobacillus plantarum 70810. With the exception of L. helveticus MB2-1, the other three selected strains had good growth performances in NBM with viable counts increased to log 8.30-8.39 cfu ml(-1) during 6 h of fermentation, and thus were selected for the following investigations. Protein contents of NBM significantly reduced when treated with L. bulgaricus and L. plantarum B1-6, and the electrophoresis patterns showed the preferable proteins for LAB strains to hydrolyze were ?- and ?-type phaseolins, whereas ?-type phaseolin was resistant to hydrolysis. RP-HPLC analysis demonstrated all fermented NBM had higher intensities of peaks with retention times between 2.5 and 3.5 min indicative of formation of small peptides. All fermented NBM showed higher ACE inhibitory activity compared to the unfermented ones, for which 2 h, 3 h, and 5 h were found to be the optimum fermentation periods for respectively L. plantarum 70810, L. plantarum B1-6 and L. bulgaricus, with IC50 values of 109 ± 5.1, 108 ± 1.1, and 101 ± 2.2 ?g protein ml(-1). The subsequent in vitro gastrointestinal simulation afforded all fermented extracts reduced IC50 values and the extracts fermented by L. plantarum B1-6 exerted the lowest IC50 value of 21 ± 2.1 ?g protein ml(-1). The research has broadened our knowledge bases on the effect of LAB fermentation on the degradation of navy bean proteins and the capacity to release ACE inhibitory peptides. The approach was promising to obtain probiotic products with potential to serve as functional ingredients targeting hypertension. PMID:25536445

  1. Analyses of Spatial Distributions of Sulfate-Reducing Bacteria and Their Activity in Aerobic Wastewater Biofilms

    PubMed Central

    Okabe, Satoshi; Itoh, Tsukasa; Satoh, Hisashi; Watanabe, Yoshimasa

    1999-01-01

    The vertical distribution of sulfate-reducing bacteria (SRB) in aerobic wastewater biofilms grown on rotating disk reactors was investigated by fluorescent in situ hybridization (FISH) with 16S rRNA-targeted oligonucleotide probes. To correlate the vertical distribution of SRB populations with their activity, the microprofiles of O2, H2S, NO2?, NO3?, NH4+, and pH were measured with microelectrodes. In addition, a cross-evaluation of the FISH and microelectrode analyses was performed by comparing them with culture-based approaches and biogeochemical measurements. In situ hybridization revealed that a relatively high abundance of the probe SRB385-stained cells (approximately 109 to 1010 cells per cm3 of biofilm) were evenly distributed throughout the biofilm, even in the oxic surface. The probe SRB660-stained Desulfobulbus spp. were found to be numerically important members of SRB populations (approximately 108 to 109 cells per cm3). The result of microelectrode measurements showed that a high sulfate-reducing activity was found in a narrow anaerobic zone located about 150 to 300 ?m below the biofilm surface and above which an intensive sulfide oxidation zone was found. The biogeochemical measurements showed that elemental sulfur (S0) was an important intermediate of the sulfide reoxidation in such thin wastewater biofilms (approximately 1,500 ?m), which accounted for about 75% of the total S pool in the biofilm. The contribution of an internal Fe-sulfur cycle to the overall sulfur cycle in aerobic wastewater biofilms was insignificant (less than 1%) due to the relatively high sulfate reduction rate. PMID:10543829

  2. Isolation of Optically Targeted Single Bacteria by Application of Fluidic Force Microscopy to Aerobic Anoxygenic Phototrophs from the Phyllosphere

    PubMed Central

    Stiefel, Philipp; Zambelli, Tomaso

    2013-01-01

    In their natural environment, bacteria often behave differently than they do under laboratory conditions. To gain insight into the physiology of bacteria in situ, dedicated approaches are required to monitor their adaptations and specific behaviors under environmental conditions. Optical microscopy is crucial for the observation of fundamental characteristics of bacteria, such as cell shape, size, and marker gene expression. Here, fluidic force microscopy (FluidFM) was exploited to isolate optically selected bacteria for subsequent identification and characterization. In this study, bacteriochlorophyll-producing bacteria, which can be visualized due to their characteristic fluorescence in the infrared range, were isolated from leaf washes. Bacterial communities from the phyllosphere were investigated because they harbor genes indicative of aerobic anoxygenic photosynthesis. Our data show that different species of Methylobacterium express their photosystem in planta, and they show a distinct pattern of bacteriochlorophyll production under laboratory conditions that is dependent on supplied carbon sources. PMID:23770907

  3. Isolation of optically targeted single bacteria by application of fluidic force microscopy to aerobic anoxygenic phototrophs from the phyllosphere.

    PubMed

    Stiefel, Philipp; Zambelli, Tomaso; Vorholt, Julia A

    2013-08-01

    In their natural environment, bacteria often behave differently than they do under laboratory conditions. To gain insight into the physiology of bacteria in situ, dedicated approaches are required to monitor their adaptations and specific behaviors under environmental conditions. Optical microscopy is crucial for the observation of fundamental characteristics of bacteria, such as cell shape, size, and marker gene expression. Here, fluidic force microscopy (FluidFM) was exploited to isolate optically selected bacteria for subsequent identification and characterization. In this study, bacteriochlorophyll-producing bacteria, which can be visualized due to their characteristic fluorescence in the infrared range, were isolated from leaf washes. Bacterial communities from the phyllosphere were investigated because they harbor genes indicative of aerobic anoxygenic photosynthesis. Our data show that different species of Methylobacterium express their photosystem in planta, and they show a distinct pattern of bacteriochlorophyll production under laboratory conditions that is dependent on supplied carbon sources. PMID:23770907

  4. Characterization of lactic acid bacteria isolated from infant faeces as potential probiotic starter cultures for fermented sausages.

    PubMed

    Rubio, Raquel; Jofré, Anna; Martín, Belén; Aymerich, Teresa; Garriga, Margarita

    2014-04-01

    A total of 109 lactic acid bacteria isolated from infant faeces were identified by partial 16S rRNA, cpn60 and/or pheS sequencing. Lactobacillus was the most prevalent genus, representing 48% of the isolates followed by Enterococcus (38%). Lactobacillus gasseri (21%) and Enterococcus faecalis (38%) were the main species detected. A further selection of potential probiotic starter cultures for fermented sausages focused on Lactobacillus as the most technologically relevant genus in this type of product. Lactobacilli strains were evaluated for their ability to grow in vitro in the processing conditions of fermented sausages and for their functional and safety properties, including antagonistic activity against foodborne pathogens, survival from gastrointestinal tract conditions (acidity, bile and pancreatin), tyramine production, antibiotic susceptibility and aggregation capacity. The best strains according to the results obtained were Lactobacillus casei/paracasei CTC1677, L. casei/paracasei CTC1678, Lactobacillus rhamnosus CTC1679, L. gasseri CTC1700, L. gasseri CTC1704, Lactobacillus fermentum CTC1693. Those strains were further assayed as starter cultures in model sausages. L. casei/paracasei CTC1677, L. casei/paracasei CTC1678 and L. rhamnosus CTC1679 were able to lead the fermentation and dominate (levels ca. 10(8) CFU/g) the endogenous lactic acid bacteria, confirming their suitability as probiotic starter cultures. PMID:24290655

  5. In Situ Production of Exopolysaccharides during Sourdough Fermentation by Cereal and Intestinal Isolates of Lactic Acid Bacteria

    PubMed Central

    Tieking, Markus; Korakli, Maher; Ehrmann, Matthias A.; Gänzle, Michael G.; Vogel, Rudi F.

    2003-01-01

    EPS formed by lactobacilli in situ during sourdough fermentation may replace hydrocolloids currently used as texturizing, antistaling, or prebiotic additives in bread production. In this study, a screening of >100 strains of cereal-associated and intestinal lactic acid bacteria was performed for the production of exopolysaccharides (EPS) from sucrose. Fifteen strains produced fructan, and four strains produced glucan. It was remarkable that formation of glucan and fructan was most frequently found in intestinal isolates and strains of the species Lactobacillus reuteri, Lactobacillus pontis, and Lactobacillus frumenti from type II sourdoughs. By the use of PCR primers derived from conserved amino acid sequences of bacterial levansucrase genes, it was shown that 6 of the 15 fructan-producing lactobacilli and none of 20 glucan producers or EPS-negative strains carried a levansucrase gene. In sourdough fermentations, it was determined whether those strains producing EPS in MRS medium modified as described by Stolz et al. (37) and containing 100 g of sucrose liter?1 as the sole source of carbon also produce the same EPS from sucrose during sourdough fermentation in the presence of 12% sucrose. For all six EPS-producing strains evaluated in sourdough fermentations, in situ production of EPS at levels ranging from 0.5 to 2 g/kg of flour was demonstrated. Production of EPS from sucrose is a metabolic activity that is widespread among sourdough lactic acid bacteria. Thus, the use of these organisms in bread production may allow the replacement of additives. PMID:12571016

  6. Yeasts and lactic acid bacteria microbiota from masau (Ziziphus mauritiana) fruits and their fermented fruit pulp in Zimbabwe.

    PubMed

    Nyanga, Loveness K; Nout, Martinus J R; Gadaga, Tendekayi H; Theelen, Bart; Boekhout, Teun; Zwietering, Marcel H

    2007-11-30

    Masau are Zimbabwean wild fruits, which are usually eaten raw and/ or processed into products such as porridge, traditional cakes, mahewu and jam. Yeasts, yeast-like fungi, and lactic acid bacteria present on the unripe, ripe and dried fruits, and in the fermented masau fruits collected from Muzarabani district in Zimbabwe were isolated and identified using physiological and molecular methods. The predominant species were identified as Saccharomyces cerevisiae, Issatchenkia orientalis, Pichia fabianii and Aureobasidium pullulans. A. pullulans was the dominant species on the unripe fruits but was not isolated from the fermented fruit pulp. S. cerevisiae and I. orientalis were predominant in the fermented fruit pulp but were not detected in the unripe fruits. S. cerevisiae, I. orientalis, P. fabianii and S. fibuligera are fermentative yeasts and these might be used in the future development of starter cultures to produce better quality fermented products from masau fruit. Lactic acid bacteria were preliminary identified and the predominant strains found were Lactobacillus agilis and L. plantarum. Other species identified included L. bifermentans, L. minor, L. divergens, L. confusus, L. hilgardii, L. fructosus, L. fermentum and Streptococcus spp. Some of the strains of LAB could also potentially be used in a mixed-starter culture with yeasts and might contribute positively in the production of fermented masau fruit products. PMID:17904237

  7. Kinetic analysis of strains of lactic acid bacteria and acetic acid bacteria in cocoa pulp simulation media toward development of a starter culture for cocoa bean fermentation.

    PubMed

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

    2010-12-01

    The composition of cocoa pulp simulation media (PSM) was optimized with species-specific strains of lactic acid bacteria (PSM-LAB) and acetic acid bacteria (PSM-AAB). Also, laboratory fermentations were carried out in PSM to investigate growth and metabolite production of strains of Lactobacillus plantarum and Lactobacillus fermentum and of Acetobacter pasteurianus isolated from Ghanaian cocoa bean heap fermentations, in view of the development of a defined starter culture. In a first step, a selection of strains was made out of a pool of strains of these LAB and AAB species, obtained from previous studies, based on their fermentation kinetics in PSM. Also, various concentrations of citric acid in the presence of glucose and/or fructose (PSM-LAB) and of lactic acid in the presence of ethanol (PSM-AAB) were tested. These data could explain the competitiveness of particular cocoa-specific strains, namely, L. plantarum 80 (homolactic and acid tolerant), L. fermentum 222 (heterolactic, citric acid fermenting, mannitol producing, and less acid tolerant), and A. pasteurianus 386B (ethanol and lactic acid oxidizing, acetic acid overoxidizing, acid tolerant, and moderately heat tolerant), during the natural cocoa bean fermentation process. For instance, it turned out that the capacity to use citric acid, which was exhibited by L. fermentum 222, is of the utmost importance. Also, the formation of mannitol was dependent not only on the LAB strain but also on environmental conditions. A mixture of L. plantarum 80, L. fermentum 222, and A. pasteurianus 386B can now be considered a mixed-strain starter culture for better controlled and more reliable cocoa bean fermentation processes. PMID:20889778

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

    PubMed Central

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

    2010-01-01

    The composition of cocoa pulp simulation media (PSM) was optimized with species-specific strains of lactic acid bacteria (PSM-LAB) and acetic acid bacteria (PSM-AAB). Also, laboratory fermentations were carried out in PSM to investigate growth and metabolite production of strains of Lactobacillus plantarum and Lactobacillus fermentum and of Acetobacter pasteurianus isolated from Ghanaian cocoa bean heap fermentations, in view of the development of a defined starter culture. In a first step, a selection of strains was made out of a pool of strains of these LAB and AAB species, obtained from previous studies, based on their fermentation kinetics in PSM. Also, various concentrations of citric acid in the presence of glucose and/or fructose (PSM-LAB) and of lactic acid in the presence of ethanol (PSM-AAB) were tested. These data could explain the competitiveness of particular cocoa-specific strains, namely, L. plantarum 80 (homolactic and acid tolerant), L. fermentum 222 (heterolactic, citric acid fermenting, mannitol producing, and less acid tolerant), and A. pasteurianus 386B (ethanol and lactic acid oxidizing, acetic acid overoxidizing, acid tolerant, and moderately heat tolerant), during the natural cocoa bean fermentation process. For instance, it turned out that the capacity to use citric acid, which was exhibited by L. fermentum 222, is of the utmost importance. Also, the formation of mannitol was dependent not only on the LAB strain but also on environmental conditions. A mixture of L. plantarum 80, L. fermentum 222, and A. pasteurianus 386B can now be considered a mixed-strain starter culture for better controlled and more reliable cocoa bean fermentation processes. PMID:20889778

  9. Dynamics and biodiversity of populations of lactic acid bacteria and acetic acid bacteria involved in spontaneous heap fermentation of cocoa beans in Ghana.

    PubMed

    Camu, Nicholas; De Winter, Tom; Verbrugghe, Kristof; Cleenwerck, Ilse; Vandamme, Peter; Takrama, Jemmy S; Vancanneyt, Marc; De Vuyst, Luc

    2007-03-01

    The Ghanaian cocoa bean heap fermentation process was studied through a multiphasic approach, encompassing both microbiological and metabolite target analyses. A culture-dependent (plating and incubation, followed by repetitive-sequence-based PCR analyses of picked-up colonies) and culture-independent (denaturing gradient gel electrophoresis [DGGE] of 16S rRNA gene amplicons, PCR-DGGE) approach revealed a limited biodiversity and targeted population dynamics of both lactic acid bacteria (LAB) and acetic acid bacteria (AAB) during fermentation. Four main clusters were identified among the LAB isolated: Lactobacillus plantarum, Lactobacillus fermentum, Leuconostoc pseudomesenteroides, and Enterococcus casseliflavus. Other taxa encompassed, for instance, Weissella. Only four clusters were found among the AAB identified: Acetobacter pasteurianus, Acetobacter syzygii-like bacteria, and two small clusters of Acetobacter tropicalis-like bacteria. Particular strains of L. plantarum, L. fermentum, and A. pasteurianus, originating from the environment, were well adapted to the environmental conditions prevailing during Ghanaian cocoa bean heap fermentation and apparently played a significant role in the cocoa bean fermentation process. Yeasts produced ethanol from sugars, and LAB produced lactic acid, acetic acid, ethanol, and mannitol from sugars and/or citrate. Whereas L. plantarum strains were abundant in the beginning of the fermentation, L. fermentum strains converted fructose into mannitol upon prolonged fermentation. A. pasteurianus grew on ethanol, mannitol, and lactate and converted ethanol into acetic acid. A newly proposed Weissella sp., referred to as "Weissella ghanaensis," was detected through PCR-DGGE analysis in some of the fermentations and was only occasionally picked up through culture-based isolation. Two new species of Acetobacter were found as well, namely, the species tentatively named "Acetobacter senegalensis" (A. tropicalis-like) and "Acetobacter ghanaensis" (A. syzygii-like). PMID:17277227

  10. Spontaneous organic cocoa bean box fermentations in Brazil are characterized by a restricted species diversity of lactic acid bacteria and acetic acid bacteria.

    PubMed

    Papalexandratou, Zoi; Vrancken, Gino; De Bruyne, Katrien; Vandamme, Peter; De Vuyst, Luc

    2011-10-01

    Spontaneous organic cocoa bean box fermentations were carried out on two different farms in Brazil. Physical parameters, microbial growth, bacterial species diversity [mainly lactic acid bacteria (LAB) and acetic acid bacteria (AAB)], and metabolite kinetics were monitored, and chocolates were produced from the fermented dry cocoa beans. The main end-products of the catabolism of the pulp substrates (glucose, fructose, and citric acid) by yeasts, LAB, and AAB were ethanol, lactic acid, mannitol, and/or acetic acid. Lactobacillus fermentum and Acetobacter pasteurianus were the predominating bacterial species of the fermentations as revealed through (GTG)(5)-PCR fingerprinting of isolates and PCR-DGGE of 16S rRNA gene PCR amplicons of DNA directly extracted from fermentation samples. Fructobacillus pseudoficulneus, Lactobacillus plantarum, and Acetobacter senegalensis were among the prevailing species during the initial phase of the fermentations. Also, three novel LAB species were found. This study emphasized the possible participation of Enterobacteriaceae in the cocoa bean fermentation process. Tatumella ptyseos and Tatumella citrea were the prevailing enterobacterial species in the beginning of the fermentations as revealed by 16S rRNA gene-PCR-DGGE. Finally, it turned out that control over a restricted bacterial species diversity during fermentation through an ideal post-harvest handling of the cocoa beans will allow the production of high-quality cocoa and chocolates produced thereof, independent of the fermentation method or farm. PMID:21839382

  11. Production of wax esters during aerobic growth of marine bacteria on isoprenoid compounds

    PubMed

    Rontani; Bonin; Volkman

    1999-01-01

    This paper describes the production of isoprenoid wax esters during the aerobic degradation of 6,10,14-trimethylpentadecan-2-one and phytol by four bacteria (Acinetobacter sp. strain PHY9, Pseudomonas nautica [IP85/617], Marinobacter sp. strain CAB [DSMZ 11874], and Marinobacter hydrocarbonoclasticus [ATCC 49840]) isolated from the marine environment. Different pathways are proposed to explain the formation of these compounds. In the case of 6,10, 14-trimethylpentadecan-2-one, these esters result from the condensation of some acidic and alcoholic metabolites produced during the biodegradation, while phytol constitutes the alcohol moiety of most of the esters produced during growth on this isoprenoid alcohol. The amount of these esters formed increased considerably in N-limited cultures, in which the ammonium concentration corresponds to conditions often found in marine sediments. This suggests that the bacterial formation of isoprenoid wax esters might be favored in such environments. Although conflicting evidence exists regarding the stability of these esters in sediments, it seems likely that, under some conditions, bacterial esterification can enhance the preservation potential of labile compounds such as phytol. PMID:9872783

  12. Production of Wax Esters during Aerobic Growth of Marine Bacteria on Isoprenoid Compounds

    PubMed Central

    Rontani, Jean-Francois; Bonin, Patricia C.; Volkman, John K.

    1999-01-01

    This paper describes the production of isoprenoid wax esters during the aerobic degradation of 6,10,14-trimethylpentadecan-2-one and phytol by four bacteria (Acinetobacter sp. strain PHY9, Pseudomonas nautica [IP85/617], Marinobacter sp. strain CAB [DSMZ 11874], and Marinobacter hydrocarbonoclasticus [ATCC 49840]) isolated from the marine environment. Different pathways are proposed to explain the formation of these compounds. In the case of 6,10,14-trimethylpentadecan-2-one, these esters result from the condensation of some acidic and alcoholic metabolites produced during the biodegradation, while phytol constitutes the alcohol moiety of most of the esters produced during growth on this isoprenoid alcohol. The amount of these esters formed increased considerably in N-limited cultures, in which the ammonium concentration corresponds to conditions often found in marine sediments. This suggests that the bacterial formation of isoprenoid wax esters might be favored in such environments. Although conflicting evidence exists regarding the stability of these esters in sediments, it seems likely that, under some conditions, bacterial esterification can enhance the preservation potential of labile compounds such as phytol. PMID:9872783

  13. Cultivation of aerobic chemoorganotrophic proteobacteria and gram-positive bacteria from a hot spring microbial mat.

    PubMed Central

    Nold, S C; Kopczynski, E D; Ward, D M

    1996-01-01

    The diversity of aerobic chemoorganotrophic bacteria inhabiting the Octopus Spring cyanobacterial mat community (Yellowstone National Park) was examined by using serial-dilution enrichment culture and a variety of enrichment conditions to cultivate the numerically significant microbial populations. The most abundant bacterial populations cultivated from dilutions to extinction were obtained from enrichment flasks which contained 9.0 x 10(2) primary producer (Synechococcus spp.) cells in the inoculum. Two isolates exhibited 16S rRNA nucleotide sequences typical of beta-proteobacteria. One of these isolates contained a 16S rRNA sequence identical to a sequence type previously observed in the mat by molecular retrieval techniques. Both are distantly related to a new sequence directly retrieved from the mat and contributed by a beta-proteobacterial community member. Phenotypically diverse gram-positive isolates genetically similar to Bacillus flavothermus were obtained from a variety of dilutions and enrichment types. These isolates exhibited identical 16S rRNA nucleotide sequences through a variable region of the molecule. Of the three unique sequences observed, only one had been previously retrieved from the mat, illustrating both the inability of the cultivation methods to describe the composition of a microbial community and the limitations of the ability of molecular retrieval techniques to describe populations which may be less abundant in microbial communities. PMID:8899976

  14. Numerical taxonomy of psychrotrophic lactic acid bacteria from prepacked meat and meat products

    Microsoft Academic Search

    Elisabeth Borch; Göran Molin

    1988-01-01

    Ninety-four strains of lactic acid bateria isolated from refrigerated, prepacked meat and meat products were together with 59 reference strains of Brochothrix, Lactobacillus, Leuconostoc, Pediococcus and Streptococcus phenotypically classfied, using 96 unit characters. Data were examined using Simple Matching (SSM) or Jaccard coefficient (SJ), and unweighted pair group algorithm with arithmetic averages. Twenty-three clusters with two or more members were

  15. Reduced biogenic amine contents in sauerkraut via addition of selected lactic acid bacteria

    Microsoft Academic Search

    Mohamed A. Rabie; Hassan Siliha; Soher el-Saidy; Ahmed A. el-Badawy; F. Xavier Malcata

    2011-01-01

    The contents of free amino acids and biogenic amines in spontaneously fermented sauerkraut, inoculated or not with specific lactic acid bacterium strains, were monitored throughout 45d of storage. The strains tested were Lactobacillus plantarum 2142, Lactobacillus casei subsp. casei 2763 and Lactobacillus curvatus 2771. In both the control and the experiments, the total amino acid contents increased with time –

  16. THE SURVIVAL OF SILAGE INOCULANT LACTIC ACID BACTERIA IN RUMEN FLUID

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Twelve commercial silage inoculants were added at 1 and 10 million CFU/ml to clarified and strained rumen fluid taken from dairy cows, respectively, with and without 5 g/l glucose. The vials of inoculated rumen fluid was incubated anaerobically at 39 C. Changes in pH, lactic acid bacterial numbers a...

  17. Stabilization of polymer lipid complexes prepared with lipids of lactic acid bacteria upon preservation and internalization into eukaryotic cells.

    PubMed

    Alves, P; Hugo, A A; Szymanowski, F; Tymczyszyn, E E; Pérez, P F; Coelho, J F J; Simões, P N; Gómez-Zavaglia, A

    2014-11-01

    The physicochemical characterization of polymer liposome complexes (PLCs) prepared with lipids of lactic acid bacteria and poly(N,N-dimethylaminoethyl methacrylate) covalently bound to cholesterol (CHO-PDMAEMA) was carried out in an integrated approach, including their stability upon preservation and incorporation into eukaryotic cells. PLCs were prepared with different polymer:lipid molar ratios (0, 0.05 and 0.10). Zeta potential, particle size distribution and polydispersity index were determined. The optimal polymer:lipid ratio and the stability of both bare liposomes and PLCs were evaluated at 37 °C and at different pHs, as well as after storage at 4 °C, -80 °C and freeze-drying in the presence or absence of trehalose 250 mM. Internalization of PLCs by eukaryotic cells was assessed to give a complete picture of the system. Incorporation of CHO-PDMAEMA onto bacterial lipids (ratio 0.05 and 0.10) led to stabilization at 37 °C and pH 7. A slight decrease of pH led to their strong destabilization. Bacteria PLCs showed to be more stable than lecithin (LEC) PLCs (used for comparison) upon preservation at 4 and -80 °C. The harmful nature of the preservation processes led to a strong decrease in the stability of PLCs, bacterial formulations being more stable than LEC PLCs. The addition of trehalose to the suspension of liposomes stabilized LEC PLC and did not have effect on bacterial PLCs. In vitro studies on Raw 264.7 and Caco-2/TC7 cells demonstrated an efficient incorporation of PLCs into the cells. Preparations with higher stability were the ones that showed a better cell-uptake. The nature of the lipid composition is determinant for the stability of PLCs. Lipids from lactic acid bacteria are composed of glycolipids and phospholipids like cardiolipin and phosphatidylglycerol. The presence of negatively charged lipids strongly improves the interaction with the positively charged CHO-PDMAEMA, thus stabilizing liposomes. In addition, glycolipids and phosphatidylglycerol act as intrinsic protectants of PLCs upon preservation. This particular lipid composition of lactic acid bacteria makes them natural formulations potentially useful as drug delivery systems. PMID:25448716

  18. Effects of Inoculants Containing Propionic Acid Bacteria on Fermentation and Aerobic Stability of Corn Silage[1] and [2

    Microsoft Academic Search

    G. E. Higginbotham; S. C. Mueller; K. K. Bolsen; E. J. DePeters

    1998-01-01

    The effects of microbial inoculants containing propionic acid bacteria on fermentation and aerobic stability of corn silage were examined. Whole-plant corn was ensiled for 3, 21, and 90 d in 5- to 7-kg capacity polyethylene bags, and six treatments were compared: no additive, Pediococcus cerevisiae at 3 × 105 cfu\\/g of fresh forage plus Lactobacillus planta- rum at 1.5 ×

  19. Detection and Quantification of Bacteria Involved in Aerobic and Anaerobic Ammonium Oxidation in an Ammonium-Contaminated Aquifer

    Microsoft Academic Search

    Theo H. M. Smits; Arne Hüttmann; David N. Lerner; Christof Holliger

    2009-01-01

    The aerobic and anaerobic ammonium-oxidizing bacterial guilds were studied from two multilevel samplers in an ammonium-contaminated aquifer in the UK. By end point polymerase chain reaction (PCR), the presence of betaproteobacterial ammonium-oxidizing bacteria and anaerobic ammonium-oxidizing (anammox) planctomycetes was demonstrated. The sequences of cloned anammox-specific PCR fragments had close relationships with known anammox strains. Real-time PCR was subsequently used to

  20. Fate of chlortetracycline- and tylosin-resistant bacteria in an aerobic thermophilic sequencing batch reactor treating swine waste.

    PubMed

    Chénier, Martin R; Juteau, Pierre

    2009-07-01

    Antibiotics have been added to animal feed for decades. Consequently, food animals and their wastes constitute a reservoir of antibiotic-resistant bacteria. The objective of this work was to characterize the impact of an aerobic thermophilic biotreatment on aerobic, antibiotic-resistant bacteria in swine waste. The proportion of tylosin- and chlortetracycline-resistant bacteria grown at 25 degrees C, 37 degrees C, and 60 degrees C decreased after treatment, but they were still abundant (10(2) to 10(8) most probable number ml(-1)) in the treated swine waste. The presence of 14 genes conferring resistance to tylosin and chlortetracycline was assessed by polymerase chain reaction in bacterial populations grown at 25 degrees C, 37 degrees C, and 60 degrees C, with or without antibiotics. In 22 cases, genes were detected before but not after treatment. The overall gene diversity was wider before [tet(BLMOSY), erm(AB)] than after [tet(LMOS), erm(B)] treatment. Analysis by denaturing gradient gel electrophoresis of amplified 16S ribosomal DNA (rDNA) fragments generally showed a reduction of the bacterial diversity, except for total populations grown at 60 degrees C and for tylosin-resistant populations grown at 37 degrees C. The latter were further investigated by cloning and sequencing their 16S rDNA. Phylotypes found before treatment were all closely related to Enterococcus hirae, whereas six different phylotypes, related to Pseudomonas, Alcaligenes, and Pusillimonas, were found after treatment. This work demonstrated that the aerobic thermophilic biotreatment cannot be considered as a means for preventing the dissemination of aerobic antibiotic-resistant bacteria and their resistance genes to the environment. However, since pathogens do not survive the biotreatment, the effluent does not represent an immediate threat to animal or human health. PMID:19125305

  1. Species diversity and relative abundance of lactic acid bacteria in the milk of rhesus monkeys (Macaca mulatta)

    PubMed Central

    Jin, L.; Hinde, K.; Tao, L.

    2013-01-01

    Background Mother’s milk is a source of bacteria that influences the development of the infant commensal gut microbiota. To date, the species diversity and relative abundance of lactic acid bacteria in the milk of non-human primates have not been described. Methods Milk samples were aseptically obtained from 54 female rhesus monkeys (Macaca mulatta) at peak lactation. Following GM17 and MRS agar plating, single bacterial colonies were isolated based on difference in morphotypes, then grouped based on whole-cell protein profiles on SDS–PAGE. Bacterial DNA was isolated and the sequence the 16S rRNA gene was analyzed. Results A total of 106 strains of 19 distinct bacterial species, belonging to five genera, Bacillus, Enterococcus, Lactobacillus, Pediococcus, and Streptococcus, were identified. Conclusions Maternal gut and oral commensal bacteria may be translocated to the mammary gland during lactation and present in milk. This pathway can be an important source of commensal bacteria to the infant gut and oral cavity. PMID:20946146

  2. Selection of lactic acid bacteria from Brazilian kefir grains for potential use as starter or probiotic cultures.

    PubMed

    Zanirati, Débora Ferreira; Abatemarco, Mário; Sandes, Sávio Henrique de Cicco; Nicoli, Jacques Robert; Nunes, Álvaro Cantini; Neumann, Elisabeth

    2015-04-01

    Brazilian kefir is a homemade fermented beverage that is obtained by incubating milk or a brown sugar solution with kefir grains that contribute their different microbiological compositions. It is highly important to isolate and characterize microorganisms from Brazilian kefir grains to obtain starter cultures for the industrial production of a standardized commercial kefir. Thus, the present study aimed to isolate lactic acid bacteria from eight kefir grains that were propagated in milk or sugar solutions from five different locations in Brazil and to select Lactobacillus isolates based on desirable in vitro probiotic properties. One hundred eight isolates from both substrates were identified by amplified ribosomal DNA restriction analysis and/or 16S rRNA gene sequencing and were determined to belong to the following 11 species from the genera: Lactococcus, Leuconostoc, Lactobacillus (L.), and Oenococcus. Leuconostoc mesenteroides, Lactobacillus kefiri, and Lactobacillus kefiranofaciens were isolated only from milk grains, whereas Lactobacillus perolens, Lactobacillus parafarraginis, Lactobacillus diolivorans, and Oenococcus oeni were isolated exclusively from sugar water grains. When the microbial compositions of four kefir grains were evaluated with culture-independent analyses, L. kefiranofaciens was observed to predominant in milk grains, whereas Lactobacillus hilgardii was most abundant in sugar water kefir. Unfortunately, L. hilgardii was not isolated from any grain, although this bacteria was detected with a culture-independent methodology. Fifty-two isolated Lactobacilli were tested for gastric juice and bile salt tolerance, antagonism against pathogens, antimicrobial resistance, and surface hydrophobicity. Three Lactobacillus strains (L. kefiranofaciens 8U, L. diolivorans 1Z, and Lactobacillus casei 17U) could be classified as potential probiotics. In conclusion, several lactic acid bacteria that could be used in combination with yeasts as starter cultures for both milk kefir and sugar water kefir were characterized, and the functional properties of several of the lactobacilli isolated from the kefir grains were suggestive of their possible use as probiotics in both kefir and other dairy products. PMID:25542841

  3. A description of the lactic acid bacteria microbiota associated with the production of traditional fermented vegetables in Vietnam.

    PubMed

    Nguyen, Doan Thi Lam; Van Hoorde, Koenraad; Cnockaert, Margo; De Brandt, Evie; Aerts, Maarten; Binh Thanh, Le; Vandamme, Peter

    2013-04-15

    An important part of the daily nourishment in Vietnam constitutes of fermented vegetables. Bacteria and especially lactic acid bacteria play a central role in the production of many fermented vegetables. The current study was conducted to investigate the diversity of native lactic acid bacteria (LAB) populations in 'dua muoi' (mustard and beet fermentation) and 'ca muoi' (eggplant fermentation), three types of popular traditional fermented vegetables of Vietnamese origin. To this end a polyphasic approach combining matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and pheS gene sequence analysis was used. In addition, denaturing gradient gel electrophoresis was performed as a culture-independent method to complement the observed culturable diversity data. A total of 881 LAB isolates were recovered from 21 different samples. Predominant LAB associated with 'dua muoi' and 'ca muoi' were identified as Lactobacillus fermentum (56.6%), Lactobacillus pentosus (24.4%) and Lactobacillus plantarum (17.1%). Less abundant species were Pediococcus pentosaceus (1.0%) and Lactobacillus brevis (0.5%). Species present less than 0.1% included Lactobacillus paracasei, Lactobacillus pantheris and Pediococcus acidilactici. In contrast to fermented mustard and beet with the highest prevalence of L. fermentum, the species most recovered from fermented eggplant samples was L. pentosus. In addition, an important degree of genetic variability within the different predominant species was observed and strain dependency correlating with the type of fermented vegetable or location of production could be demonstrated using multivariate statistics. This research gives an extensive and detailed inventory of the LAB diversity associated with the production of diverse Vietnamese fermented vegetables and demonstrates the influence of type of raw material and/or production location and conditions on this diversity. PMID:23500611

  4. Detection of alternative nitrogenases in aerobic gram-negative nitrogen-fixing bacteria.

    PubMed Central

    Fallik, E; Chan, Y K; Robson, R L

    1991-01-01

    Strains of aerobic, microaerobic, nonsymbiotic, and symbiotic dinitrogen-fixing bacteria were screened for the presence of alternative nitrogenase (N2ase) genes by DNA hybridization between genomic DNA and DNA encoding structural genes for components 1 of three different enzymes. A nifDK gene probe was used as a control to test for the presence of the commonly occurring Mo-Fe N2ase, a vnfDGK gene probe was used to show the presence of V-Fe N2ase, and an anfDGK probe was used to detect Fe N2ase. Hitherto, all three enzymes have been identified in Azotobacter vinelandii OP, and all but the Fe N2ase are present in Azotobacter chroococcum ATCC 4412 (MCD1). Mo-Fe N2ase and V-Fe N2ase structural genes only were confirmed in this strain and in two other strains of A. chroococcum (ATCC 480 and ATCC 9043). A similar pattern was observed with Azotobacter beijerinckii ATCC 19360 and Azotobacter nigricans ATCC 35009. Genes for all three systems are apparently present in two strains of Azotobacter paspali (ATCC 23367 and ATCC 23833) and also in Azomonas agilis ATCC 7494. There was no good evidence for the existence of any genes other than Mo-Fe N2ase structural genes in several Rhizobium meliloti strains, cowpea Rhizobium strain 32H1, or Bradyrhizobium japonicum. Nitrogenase and nitrogenase genes in Azorhizobium caulinodans behaved in an intermediate fashion, showing (i) the formation of ethane from acetylene under Mo starvation, a characteristic of alternative nitrogenases, and (ii) a surprising degree of cross-hybridization to the vnfDGK, but not the anfDGK, probe. vnfDGK- and anfDGK-like sequences were not detected in two saccharolytic Pseudomonas species or Azospirillum brasilense Sp7. The occurrence of alternative N2ases seems restricted to members of the family Azotobacteraceae among the aerobic and microaerobic diazotrophs tested, suggesting that an ability to cope with O2 when fixing N2 may be an important factor influencing the distribution of alternative nitrogenases. Images PMID:1987127

  5. Characterization of aerobic spore-forming bacteria associated with industrial dairy processing environments and product spoilage.

    PubMed

    Lücking, Genia; Stoeckel, Marina; Atamer, Zeynep; Hinrichs, Jörg; Ehling-Schulz, Monika

    2013-09-01

    Due to changes in the design of industrial food processing and increasing international trade, highly thermoresistant spore-forming bacteria are an emerging problem in food production. Minimally processed foods and products with extended shelf life, such as milk products, are at special risk for contamination and subsequent product damages, but information about origin and food quality related properties of highly heat-resistant spore-formers is still limited. Therefore, the aim of this study was to determine the biodiversity, heat resistance, and food quality and safety affecting characteristics of aerobic spore-formers in the dairy sector. Thus, a comprehensive panel of strains (n=467), which originated from dairy processing environments, raw materials and processed foods, was compiled. The set included isolates associated with recent food spoilage cases and product damages as well as isolates not linked to product spoilage. Identification of the isolates by means of Fourier-transform infrared spectroscopy and molecular methods revealed a large biodiversity of spore-formers, especially among the spoilage associated isolates. These could be assigned to 43 species, representing 11 genera, with Bacillus cereus s.l. and Bacillus licheniformis being predominant. A screening for isolates forming thermoresistant spores (TRS, surviving 100°C, 20 min) showed that about one third of the tested spore-formers was heat-resistant, with Bacillus subtilis and Geobacillus stearothermophilus being the prevalent species. Strains producing highly thermoresistant spores (HTRS, surviving 125°C, 30 min) were found among mesophilic as well as among thermophilic species. B. subtilis and Bacillus amyloliquefaciens were dominating the group of mesophilic HTRS, while Bacillus smithii and Geobacillus pallidus were dominating the group of thermophilic HTRS. Analysis of spoilage-related enzymes of the TRS isolates showed that mesophilic strains, belonging to the B. subtilis and B. cereus groups, were strongly proteolytic, whereas thermophilic strains displayed generally a low enzymatic activity and thus spoilage potential. Cytotoxicity was only detected in B. cereus, suggesting that the risk of food poisoning by aerobic, thermoresistant spore-formers outside of the B. cereus group is rather low. PMID:23973839

  6. Comparison between rinse and crush-and-rub sampling for aerobic bacteria recovery from broiler hatching eggs after sanitization.

    PubMed

    Spickler, J L; Buhr, R J; Cox, N A; Bourassa, D V; Rigsby, L L

    2011-07-01

    This study compared surface and deep eggshell aerobic bacteria recovered by the rinse and crush-and-rub sampling methods for commercial hatching eggs after treatment with sanitizers. Eggs were arranged into 5 treatments consisting of no treatment, water, and 3 sanitizers. The sanitizers were H(2)O(2), phenol, and Q(4)B (a compound chemical containing 4 quaternary ammoniums and 1 biguanide moiety). Eggs were sprayed according to treatment and allowed to dry for 1 h before sampling. To collect samples for the eggshell rinse, each egg was massaged in a plastic bag with 20 mL of saline. Eggshells were then aseptically opened and their contents were discarded before being individually crushed into 50-mL centrifuge tubes containing 20 mL of saline. Aerobic bacteria were enumerated on Petrifilm after 48 h of incubation at 37°C. Aerobic bacteria recovered (log(10) cfu/mL) from the eggshell rinse were highest and similar for the no-treatment (4.0) and water (3.7) groups, lower for the phenol (3.2) and H(2)O(2) (3.1) groups, and lowest for the Q(4)B (2.4) group. Aerobic bacteria levels with the crush-and-rub method were similar for the no-treatment (2.5) and water (2.3) groups, lower for the phenol (1.6) group, intermediate for the H(2)O(2) (1.2) group, and lowest for the Q(4)B (0.9) group. The overall correlation between the rinse and crush-and-rub sampling methods for individual egg aerobic bacteria counts was r = 0.71. The correlation within each treatment revealed the following r values: no treatment, 0.55; water, 0.72; H(2)O(2), 0.67; phenol, 0.73; and Q(4)B, 0.38. A second experiment was designed to further examine the lower aerobic bacterial levels recovered by the crush-and-rub method (for previously rinsed eggs) than the levels recovered in the initial eggshell rinse sample. Eggs were either rinsed and then crushed and rubbed, or they were only crushed and rubbed without a prior rinse. Results confirmed a significant decrease (1.5 log(10) cfu/mL) in bacteria levels between the initial rinse (4.4) and the subsequent crush and rub (2.9) for the same eggshell. For the crush-and-rub eggs with no previous rinsing, the bacteria recovery level (3.9) was not significantly different from levels for the rinse method. Therefore, either the rinse or crush-and-rub sampling methods can be used to recover similar levels of eggshell aerobic bacteria. PMID:21673179

  7. Use of the Escherichia coli beta-glucuronidase (gusA) gene as a reporter gene for analyzing promoters in lactic acid bacteria.

    PubMed

    Platteeuw, C; Simons, G; de Vos, W M

    1994-02-01

    A transcriptional fusion vector, designated pNZ272, based on the promoterless beta-glucuronidase gene (gusA) of Escherichia coli as a reporter gene, has been constructed for lactic acid bacteria. The replicon of pNZ272 was derived from the Lactococcus lactis plasmid pSH71, allowing replication in a wide range of gram-positive bacteria and E. coli. The applicability of pNZ272 and the expression of the gusA gene in L. lactis was demonstrated in shotgun cloning experiments with lactococcal chromosomal and bacteriophage DNA. In addition, three defined lactococcal promoters were inserted in pNZ272: the plasmid-derived lacA promoter, the chromosomal usp45 promoter, and a promoter from bacteriophage phi SK11G. The three resulting plasmids showed beta-glucuronidase activity in a gusA-deficient E. coli strain and in four species of lactic acid bacteria belonging to the genera Lactobacillus, Lactococcus, and Leuconostoc. The copy numbers of the gusA-expressing plasmids were similar within a single species of lactic acid bacteria. However, the specific beta-glucuronidase activity and the gusA mRNA levels varied considerably both within a single species and among different species of lactic acid bacteria. The transcriptional start site of all three promoters was determined and found to be identical in the different species. The results of this comparative promoter analysis indicate that the requirements for efficient transcription initiation differ among the lactic acid bacteria studied. PMID:8135517

  8. Influence of Vaginal Bacteria and d- and l-Lactic Acid Isomers on Vaginal Extracellular Matrix Metalloproteinase Inducer: Implications for Protection against Upper Genital Tract Infections

    PubMed Central

    Witkin, Steven S.; Mendes-Soares, Helena; Linhares, Iara M.; Jayaram, Aswathi; Ledger, William J.; Forney, Larry J.

    2013-01-01

    ABSTRACT We evaluated levels of vaginal extracellular matrix metalloproteinase inducer (EMMPRIN) and matrix metalloproteinase (MMP-8) in vaginal secretions in relation to the composition of vaginal bacterial communities and d- and l-lactic acid levels. The composition of vaginal bacterial communities in 46 women was determined by pyrosequencing the V1 to V3 region of 16S rRNA genes. Lactobacilli were dominant in 71.3% of the women, followed by Gardnerella (17.4%), Streptococcus (8.7%), and Enterococcus (2.2%). Of the lactobacillus-dominated communities, 51.5% were dominated by Lactobacillus crispatus, 36.4% by Lactobacillus iners, and 6.1% each by Lactobacillus gasseri and Lactobacillus jensenii. Concentrations of l-lactic acid were slightly higher in lactobacillus-dominated vaginal samples, but most differences were not statistically significant. d-Lactic acid levels were higher in samples containing L. crispatus than in those with L. iners (P < 0.0001) or Gardnerella (P = 0.0002). The relative proportion of d-lactic acid in vaginal communities dominated by species of lactobacilli was in concordance with the proportions found in axenic cultures of the various species grown in vitro. Levels of l-lactic acid (P < 0.0001) and the ratio of l-lactic acid to d-lactic acid (P = 0.0060), but not concentrations of d-lactic acid, were also correlated with EMMPRIN concentrations. Moreover, vaginal concentrations of EMMPRIN and MMP-8 levels were highly correlated (P < 0.0001). Taken together, the data suggest the relative proportion of l- to d-lactic acid isomers in the vagina may influence the extent of local EMMPRIN production and subsequent induction of MMP-8. The expression of these proteins may help determine the ability of bacteria to transverse the cervix and initiate upper genital tract infections. PMID:23919998

  9. Effect of storage temperature and gas permeability of packaging film on the growth of lactic acid bacteria and Brochothrix thermosphacta in cooked meat emulsions

    Microsoft Academic Search

    O. Garroa; C. Fernandez

    The effect of gas permeability of packaging film on the growth of lactic acid bacteria and Brochothrix thermosphacta in cooked meat emulsions stored at 0, 8 and 151C was investigated. The estimated parameters from Gompertz equation for the assayed temperature-oxygen permeability combinations showed LAB development to be significantly greater than those of B. thermosphacta. The influence of the two sources

  10. Use of starter cultures of lactic acid bacteria and yeasts as inoculum enrichment for the production of gowé, a sour beverage from Benin

    Microsoft Academic Search

    Vieira-Dalodé G; Madodé Y. E

    Lactobacillus fermentum, Weissella confusa, Kluyveromyces marxianus and Pichia anomala, previously isolated during natural fermentation of traditional gowé, were tested as inoculum enrichment for controlled fermentation of gowé. The final product was subjected to chemical analysis and sensory evaluation. Growth of the lactic acid bacteria (LAB) and yeasts were verified by determination of colony forming units (CFU) and molecular biology techniques.

  11. Antimicrobial properties of lactic acid bacteria and yeast-LAB cultures isolated from traditional fermented milk against pathogenic Escherichia coli and Salmonella enteritidis strains

    Microsoft Academic Search

    J. Mufandaedza; B. C. Viljoen; S. B. Feresu; T. H. Gadaga

    2006-01-01

    The survival and growth of Escherichia coli 3339 and Salmonella enteritidis 949575 isolated from human clinical samples, in milk fermented with lactic acid bacteria (LAB) and yeast strains previously isolated from Zimbabwean naturally fermented milk (NFM) was studied. The LAB starter cultures used were Lactococcus lactis subsp. lactis biovar. diacetylactis C1 alone (C1) or in combination with Candida kefyr 23

  12. The Sourdough Microflora. Characterization of Hetero and Homofermentative Lactic Acid Bacteria, Yeasts and Their Interactions on the Basis of the Volatile Compounds Produced

    Microsoft Academic Search

    P. Damiani; M. Gobbetti; L. Cossignani; A. Corsetti; M. S. Simonetti; J. Rossi

    1996-01-01

    Eighty-seven strains (15 species) of sourdough lactic acid bacteria (homo- and hetero-fermentative) and yeasts were characterized and statistically discriminated on the basis of volatile compounds produced during sourdough fermentation. The species differed and, in general, the strains differed within the species. Heterofermentative LAB mainly produced ethylacetate with some alcohols and aldehydes, and homofermentative LAB synthetized diacetyl and other carbonyls, while

  13. Effect of lactic acid bacteria inoculant and beet pulp addition on fermentation characteristics and in vitro ruminal digestion of vegetable residue silage

    Microsoft Academic Search

    Y. Cao; Y. Cai; T. Takahashi; N. Yoshida; M. Tohno; R. Uegaki; K. Nonaka; F. Terada

    2011-01-01

    The objective of this study was to determine the effect of beet pulp (BP) and lactic acid bacteria (LAB) on silage fermentation quality and in vitro ruminal dry matter (DM) digestion of vegetable residues, including white cabbage, Chinese cabbage, red cabbage, and lettuce. Silage was prepared using a small-scale fermentation system, and treatments were designed as control silage without additive

  14. Growth and survival of Atlantic salmon ( Salmo salar) fry given diets supplemented with fish protein hydrolysate and lactic acid bacteria during a challenge trial with Aeromonas salmonicida

    Microsoft Academic Search

    Asbjørn Gildberg; Audny Johansen; Jarl Bøgwald

    1995-01-01

    Atlantic salmon fry were reared ad libitum on a commercial fish feed supplemented with 10% cod muscle protein (A), 10% hydrolyzed cod muscle protein (B) or 10% of a hydrolysate based culture of lactic acid bacteria isolated from salmon intestines. The fry grew well, and equally so, on each of the three diets (specific growth rate, 2.5% day?1). Very low

  15. Biodiversity and characterization of aerobic spore-forming bacteria in surimi seafood products.

    PubMed

    Coton, M; Denis, C; Cadot, P; Coton, E

    2011-04-01

    The microbial quality and safety of surimi seafood products was assessed by studying the prevalence and biodiversity of aerobic spore-forming bacteria at the beginning and end of shelf life in 100 surimi samples. Low levels of total flora and sporulated flora were numerated at the beginning of storage, however, residual spores were detected in the majority of samples during storage. Furthermore, for 34 samples, total flora counts>10(4) CFU/g were observed at the end of shelf life which could lead to non-compliance with good practice recommendations or product spoilage. In total, 460 strains were isolated, fingerprinted by M13-PCR and grouped into 98 different clusters. Representative strains were then identified at the species level via 16S rRNA gene sequencing. Overall, dominant species belonged to Bacillus simplex, Bacillus subtilis and Bacillus licheniformis; while B. simplex, B. subtilis as well as Sporosarcina aquimarina were clearly the dominant species found in samples with higher total flora counts. Amylolytic and proteolytic activities were very frequent amongst tested strains (80 and 92.5%, respectively). Heat resistance parameters of 4 strains in a surimi-based medium were determined. B. simplex and B. subtilis strains were the most heat resistant (?(96 °C)= 27.6 and 23.3 min and z(T)=8.6 and 7.9, respectively) which can explain their dominance in surimi samples exhibiting higher microbial counts. The heat resistance data obtained can now be used to model thermal destruction of strains using predictive microbiology tools (Sym'Previus). PMID:21315981

  16. [Identification of aerobic and facultatively anaerobic sporulating bacteria isolated during the primary milk collection].

    PubMed

    Pácová, Z; Vyhnálková; Lukásová, J; Holec, J

    1996-01-01

    Aerobic and/or facultatively anaerobic sporulating Gram-positive bacteria of the genus Bacillus influence nutritive and sensory properties of pasteurized milk by their proteolytic and lipolytic activity. Since particularly raw milk is a source of pasteurized milk contamination by spore-producing bacteria, our investigations were focused on identification of bacilli from operations of milk agricultural primary production. The species B. licheniformis and B. cereus (Crielly et al., 1994) are the most frequently isolated ones in the process of milk production. While B. licheniformis as well as B. subtilis and B. pumilus are mesophilic species, B. cereus is rather psychrotrophic, and as to their health impacts they cause diseases from foods (Griffiths, 1990; Christiansson, 1992; Becker et al., 1994). Sixty-six strains were isolated and identified from operations of milk agricultural primary production (Tab. I). B. licheniformis occurrence (58 strains) was most frequent in the set of samples, followed by B. subtilis (5 strains), B. pumilus (one strain) and B. cereus (one strain), i.e. these are species classified to morphological group I (oval, cell-nonswelling spores). Only one strain Paenibacillus amylolyticus (formerly Bacillus amylolyticus) was isolated from morphological group II (oval, cell-swelling spores). Species representation of isolated strains is in agreement with literacy data (Phillips and Griffiths, 1986; Sutherland and Murdock, 1994; Crielly et al., 1994;). Our results did not confirm the seasonal occurrence (winter-summer) of mesophilic and psychrotrophic bacilli species as reported in literature (McKinnon and Pettipher, 1983; Sutherland and Murdock, 1994; Crielly et al., 1994). Biochemical and physiological characteristics of 66 isolates (Tab. I) are in agreement with literary data (Gordon et al., 1973; Parry et al., 1983; Priest et al., Ash et al., 1993). Strong proteolytic, amylolytic or lipolytic activities of the tested strains could influence the nutritive value of milk as a raw material. Taking into account the dominant representation of bacilli of morphological group I in raw and pasteurized milk (Sutherland and Murdock, 1994; Crielly et al., 1994) their review with basic phenotypic characteristics is shown in Tab. II. As follows from our results mesophilic species from so called "B. subtilis group" (96.9%) were isolated from agricultural primary production of milk most frequently. This is the reason why in addition to B. cereus it is also necessary to identify these species: seven tests shown in Tab III are recommended for their rapid differentiation. PMID:8619278

  17. Organic osmolytes in aerobic bacteria from Mono Lake, an alkaline, moderately hypersaline environment

    SciTech Connect

    Ciulla, R.A.; Roberts, M.F. [Boston College, Chestnut Hill, MA (United States); Diaz, M.R.; Taylor, B.F. [Univ. of Miami, FL (United States)

    1997-01-01

    The identity and concentrations of intracellular organic solutes were determined by nuclear magnetic resonance spectroscopy for two strains of aerobic, gram-negative bacteria isolated from Mono Lake, California, an alkaline, moderately hypersaline lake. Ectoine (1,4,5,6-tetrahydro-2-methyl-4-pyrimidinecarboxylic acid) was the major endogenous solute in both organisms. Concentrations of ectoine varied with external NaCl levels in strain ML-D but not in strain ML-G, where the level was high but invariant from 1.5 to 3.0 M NaCl. Hydroxyectoine also occurred in strain ML-D, especially at elevated NaCl concentrations (2.5 and 3.0 M), but at levels lower than those of ectoine. Exogenous organic solutes that might occur in Mono Lake were examined for their effects on the de novo synthesis of ectoine. Dimethylsulfoniopropionate (DMSP) (0.1 or 1 mM) did not significantly lower ectoine levels in either isolate, and only strain ML-G showed any capacity for DMSP accumulation. With nitrogen limitation, however, DMSP (0.1 mM) substituted for ectoine in strain ML-G showed any capacity for DMSP accumulation. With nitrogen limitation, however, DMSP (0.1 mM) substituted for ectoine in strain ML-G and became the main organic solute. Glycine betaine (GB) was more effective than DMSP in affecting ectoine levels, principally in strain ML-D. Strain ML-D accumulated GB to 50 or 67% of its organic solute pool at 2.5 M NaCl, at an external level of 0.1 or 1 mM GB, respectively. Strain ML-D also accumulated arsenobetaine. The methylated zwitterionic compounds, probably metabolic products of phytoplankton (DMSP and GB) or brine shrimps (arsenobetaine) in Mono Lake, may function as osmolytes for indigenous bacteria when present at high concentrations or under conditions of nitrogen limitation or salt stress. 33 refs., 5 figs., 2 tabs.

  18. Diversity and Antimicrobial Properties of Lactic Acid Bacteria Isolated from Rhizosphere of Olive Trees and Desert Truffles of Tunisia

    PubMed Central

    Najjari, Afef; Turki, Yousra; Jaballah, Sana; Boudabous, Abdelatif; Ouzari, Hadda

    2013-01-01

    A total of 119 lactic acid bacteria (LAB) were isolated, by culture-dependant method, from rhizosphere samples of olive trees and desert truffles and evaluated for different biotechnological properties. Using the variability of the intergenic spacer 16S-23S and 16S rRNA gene sequences, the isolates were identified as the genera Lactococcus, Pediococcus, Lactobacillus, Weissella, and Enterococcus. All the strains showed proteolytic activity with variable rates 42% were EPS producers, while only 10% showed the ability to grow in 9% NaCl. In addition, a low rate of antibiotic resistance was detected among rhizospheric enterococci. Furthermore, a strong antibacterial activity against plant and/or pathogenic bacteria of Stenotrophomonas maltophilia, Pantoea agglomerans, Pseudomonas savastanoi, the food-borne Staphylococcus aureus, and Listeria monocytogenes was recorded. Antifungal activity evaluation showed that Botrytis cinerea was the most inhibited fungus followed by Penicillium expansum, Verticillium dahliae, and Aspergillus niger. Most of the active strains belonged to the genera Enterococcus and Weissella. This study led to suggest that environmental-derived LAB strains could be selected for technological application to control pathogenic bacteria and to protect food safety from postharvest deleterious microbiota. PMID:24151598

  19. [Quorum sensing in class II bacteriocin-producing lactic acid bacteria and its application--a review].

    PubMed

    Zhang, Xiangmei; Li, Pinglan

    2011-09-01

    Quorum sensing (QS) refers to the behavior of microorganisms to control gene expression through detection the concentration of certain signal molecules, which is correlated with cell density. In many class II bacteriocin-producing lactic acid bacteria (LAB), bacteriocin production is regulated by peptide pheromones via a QS mechanism. We reviewed, QS regulated class II bacteriocin production in LAB and its regulation mechanism, components of the QS system, as well as the application of QS mechanism. The study of QS mechanism of class II bacteriocin-producing LAB may provide a new platform for revealing the mechanism of fermentation control and regulating fermentation process. It also offers an alternative to the exploitation of food grade gene expression system. PMID:22126069

  20. Simultaneous and successive inoculations of yeasts and lactic acid bacteria on the fermentation of an unsulfited Tannat grape must

    PubMed Central

    Muñoz, Viviana; Beccaria, Bruno; Abreo, Eduardo

    2014-01-01

    Interactions between yeasts and lactic acid bacteria are strain specific, and their outcome is expected to change in simultaneous alcoholic - malolactic fermentations from the pattern observed in successive fermentations. One Oenococcus oeni strain Lalvin VP41™ was inoculated with two Saccharomyces cerevisiae strains either simultaneously, three days after the yeast inoculation, or when alcoholic fermentation was close to finish. Early bacterial inoculations with each yeast strain allowed for the growth of the bacterial populations, and the length of malolactic fermentation was reduced to six days. Alcoholic fermentation by Lalvin ICV D80® yeast strain left the highest residual sugar, suggesting a negative effect of the bacterial growth and malolactic activity on its performance. In sequential inoculations the bacterial populations did not show actual growth with either yeast strain. In this strategy, both yeast strains finished the alcoholic fermentations, and malolactic fermentations took longer to finish. Lalvin ICV D80® allowed for higher viability and activity of the bacterial strain than Fermicru UY4® under the three inoculation strategies. This was beneficial for the sequential completion of both fermentations, but negatively affected the completion of alcoholic fermentation by Lalvin ICV D80® in the early bacteria additions. Conversely, Fermicru UY4®, which was rather inhibitory towards the bacteria, favored the timely completion of both fermentations simultaneously. As bacteria in early inoculations with low or no SO2 addition can be expected to multiply and interact with fermenting yeasts, not only are the yeast-bacterium strains combination and time point of the inoculation to be considered, but also the amount of bacteria inoculated. PMID:24948914

  1. Biodiversity of yeasts, lactic acid bacteria and acetic acid bacteria in the fermentation of "Shanxi aged vinegar", a traditional Chinese vinegar.

    PubMed

    Wu, Jia Jia; Ma, Ying Kun; Zhang, Fen Fen; Chen, Fu Sheng

    2012-05-01

    Shanxi aged vinegar is a famous traditional Chinese vinegar made from several kinds of cereal by spontaneous solid-state fermentation techniques. In order to get a comprehensive understanding of culturable microorganism's diversity present in its fermentation, the indigenous microorganisms including 47 yeast isolates, 28 lactic acid bacteria isolates and 58 acetic acid bacteria isolates were recovered in different fermenting time and characterized based on a combination of phenotypic and genotypic approaches including inter-delta/PCR, PCR-RFLP, ERIC/PCR analysis, as well as 16S rRNA and 26S rRNA partial gene sequencing. In the alcoholic fermentation, the dominant yeast species Saccharomyces (S.) cerevisiae (96%) exhibited low phenotypic and genotypic diversity among the isolates, while Lactobacillus (Lb.) fermentum together with Lb. plantarum, Lb. buchneri, Lb. casei, Pediococcus (P.) acidilactici, P. pentosaceus and Weissella confusa were predominated in the bacterial population at the same stage. Acetobacter (A.) pasteurianus showing great variety both in genotypic and phenotypic tests was the dominant species (76%) in the acetic acid fermentation stage, while the other acetic acid bacteria species including A. senegalensis, A. indonesiensis, A. malorum and A. orientalis, as well as Gluconobacter (G.) oxydans were detected at initial point of alcoholic and acetic acid fermentation stage respectively. PMID:22265314

  2. The Biodiversity of Lactic Acid Bacteria in Greek Traditional Wheat Sourdoughs Is Reflected in Both Composition and Metabolite Formation

    PubMed Central

    De Vuyst, Luc; Schrijvers, Vincent; Paramithiotis, Spiros; Hoste, Bart; Vancanneyt, Marc; Swings, Jean; Kalantzopoulos, George; Tsakalidou, Effie; Messens, Winy

    2002-01-01

    Lactic acid bacteria (LAB) were isolated from Greek traditional wheat sourdoughs manufactured without the addition of baker's yeast. Application of sodium dodecyl sulfate-polyacrylamide gel electrophoresis of total cell protein, randomly amplified polymorphic DNA-PCR, DNA-DNA hybridization, and 16S ribosomal DNA sequence analysis, in combination with physiological traits such as fructose fermentation and mannitol production, allowed us to classify the isolated bacteria into the species Lactobacillus sanfranciscensis, Lactobacillus brevis, Lactobacillus paralimentarius, and Weissella cibaria. This consortium seems to be unique for the Greek traditional wheat sourdoughs studied. Strains of the species W. cibaria have not been isolated from sourdoughs previously. No Lactobacillus pontis or Lactobacillus panis strains were found. An L. brevis-like isolate (ACA-DC 3411 t1) could not be identified properly and might be a new sourdough LAB species. In addition, fermentation capabilities associated with the LAB detected have been studied. During laboratory fermentations, all heterofermentative sourdough LAB strains produced lactic acid, acetic acid, and ethanol. Mannitol was produced from fructose that served as an additional electron acceptor. In addition to glucose, almost all of the LAB isolates fermented maltose, while fructose as the sole carbohydrate source was fermented by all sourdough LAB tested except L. sanfranciscensis. Two of the L. paralimentarius isolates tested did not ferment maltose; all strains were homofermentative. In the presence of both maltose and fructose in the medium, induction of hexokinase activity occurred in all sourdough LAB species mentioned above, explaining why no glucose accumulation was found extracellularly. No maltose phosphorylase activity was found either. These data produced a variable fermentation coefficient and a unique sourdough metabolite composition. PMID:12450829

  3. Aerobic growth of campylobacter in media supplemented with a-ketoglutaric, lactic, and/or fumaric acids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Campylobacter spp. are major causes of human foodborne illnesses, and the pathogen is widely associated with live and processed poultry. These bacteria are classified as microaerophiles and are generally cultured under atmospheres with reduced oxygen and elevated carbon dioxide concentrations. Altho...

  4. Rapid identification, by use of the LTQ Orbitrap hybrid FT mass spectrometer, of antifungal compounds produced by lactic acid bacteria.

    PubMed

    Brosnan, Brid; Coffey, Aidan; Arendt, Elke K; Furey, Ambrose

    2012-07-01

    Fungal contamination of food causes health and economic concerns. Several species of lactic acid bacteria (LAB) have antifungal activity which may inhibit food spoilage fungi. LAB have GRAS (generally recognised as safe) status, allowing them to be safely integrated into food systems as natural food preservatives. A method is described herein that enables rapid screening of LAB cultures for 25 known antifungal compounds associated with LAB. This is the first chromatographic method developed which enables the rapid identification of a wide range of antifungal compounds by a single method with a short analysis time (23 min). Chromatographic separation was achieved on a Phenomenex Gemini C18 100A column (150 mm?×?2.0 mm; 5 ?m) by use of a mobile-phase gradient prepared from (A) water containing acetic acid (0.1%) and (B) acetonitrile containing acetic acid (0.1%), at a flow rate of 0.3 µL min(-1). The gradient involved a progressive ramp from 10-95% acetonitrile over 13 min. The LC was coupled to a hybrid LTQ Orbitrap XL fourier-transform mass spectrometer (FTMS) operated in negative ionisation mode. High mass accuracy data (<3 ppm) obtained by use of high resolution (30,000 K) enabled unequivocal identification of the target compounds. This method allows comprehensive profiling and comparison of different LAB strains and is also capable of the identification of additional compounds produced by these bacteria. PMID:22526638

  5. Genetic engineering techniques for lactic acid bacteria: construction of a stable shuttle vector and expression vector for ?-glucuronidase.

    PubMed

    Chang, Shiao-Ming; Yan, Tsong-Rong

    2014-02-01

    The shuttle vector, pUL6erm, was constructed by using a replicon from pL2, a multiple cloning site, colE1 ori, the ori of Gram-negative bacteria from vector pUC19, and the erythromycin resistance gene from pVA838 as a selection marker. pUL6erm could be transformed easily and maintained stably in Lactococcus lactis, Streptococcus thermophilus, Lactobacillus plantarum and Lactobacillus casei. Transformation assays of pUL6erm indicated that it had a narrow host range. ?-Glucuronidase was induced in the presence of 0.3 M NaCl and 50 mM glutamate and expressed at 2.4 U mg(-1) with the expression vector (pUL6erm-gadR-GUS) constructed based on pUL6erm carrying ?-glucuronidase gene wuth a chloride-inducible (gadR) expression cassette using Pgad as promoter. Therefore, pUL6erm and pUL6erm-gadR-GUS might be a safe and useful genetic tool for the improvement of lactic acid bacteria. PMID:24101246

  6. Enrichment of conjugated linoleic acid (CLA) in hen eggs and broiler chickens meat by lactic acid bacteria.

    PubMed

    Herzallah, Saqer

    2013-01-01

    1. The aim of this work was to compare conjugated linoleic acid (CLA) concentrations in chickens supplemented with 4 American Tissue Culture Collection (ATCC) bacterial strains, Lactobacillus plantarum, Lactobacillus lactis, Lactobacillus casei and Lactobacillus fermentum, and 4 isolates of Lactobacillus reuteri from camel, cattle, sheep and goat rumen extracts. 2. Micro-organisms were grown anaerobically in MRS broth, and 10(6) CFU/ml of bacteria were administered orally to mixed-sex, 1-d-old broiler chickens weekly for 4 weeks and to 23-week-old layer hens weekly for 6 weeks. 3. The 4 strains were evaluated for their effects on synthesis of CLA in hen eggs and broiler meat cuts. 4. Administration of pure Lactobacillus and isolated L. reuteri strains from camel, cattle, goat and sheep led to significantly increased CLA concentrations of 0.2-1.2 mg/g of fat in eggs and 0.3-1.88 mg/g of fat in broiler chicken flesh homogenates of leg, thigh and breast. 5. These data demonstrate that lactic acid bacteria of animal origin (L. reuteri) significantly enhanced CLA synthesis in both eggs and broiler meat cuts. PMID:24397511

  7. Biodiversity and ?-Aminobutyric Acid Production by Lactic Acid Bacteria Isolated from Traditional Alpine Raw Cow's Milk Cheeses

    PubMed Central

    Nardin, Tiziana; Schiavon, Silvia; Cavazza, Agostino; Larcher, Roberto; Tuohy, Kieran M.

    2015-01-01

    “Nostrano-cheeses” are traditional alpine cheeses made from raw cow's milk in Trentino-Alto Adige, Italy. This study identified lactic acid bacteria (LAB) developing during maturation of “Nostrano-cheeses” and evaluated their potential to produce ?-aminobutyric acid (GABA), an immunologically active compound and neurotransmitter. Cheese samples were collected on six cheese-making days, in three dairy factories located in different areas of Trentino and at different stages of cheese ripening (24?h, 15 days, and 1, 2, 3, 6, and 8 months). A total of 1,059 LAB isolates were screened using Random Amplified Polymorphic DNA-PCR (RAPD-PCR) and differentiated into 583 clusters. LAB strains from dominant clusters (n = 97) were genetically identified to species level by partial 16S rRNA gene sequencing. LAB species most frequently isolated were Lactobacillus paracasei, Streptococcus thermophilus, and Leuconostoc mesenteroides. The 97 dominant clusters were also characterized for their ability in producing GABA by high-performance liquid chromatography (HPLC). About 71% of the dominant bacteria clusters evolving during cheeses ripening were able to produce GABA. Most GABA producers were Lactobacillus paracasei but other GABA producing species included Lactococcus lactis, Lactobacillus plantarum, Lactobacillus rhamnosus, Pediococcus pentosaceus, and Streptococcus thermophilus. No Enterococcus faecalis or Sc. macedonicus isolates produced GABA. The isolate producing the highest amount of GABA (80.0±2.7?mg/kg) was a Sc. thermophilus.

  8. Dynamics and species diversity of communities of lactic acid bacteria and acetic acid bacteria during spontaneous cocoa bean fermentation in vessels.

    PubMed

    Lefeber, Timothy; Gobert, William; Vrancken, Gino; Camu, Nicholas; De Vuyst, Luc

    2011-05-01

    To speed up research on the usefulness and selection of bacterial starter cultures for cocoa bean fermentation, a benchmark cocoa bean fermentation process under natural fermentation conditions was developed successfully. Therefore, spontaneous fermentations of cocoa pulp-bean mass in vessels on a 20 kg scale were tried out in triplicate. The community dynamics and kinetics of these fermentations were studied through a multiphasic approach. Microbiological analysis revealed a limited bacterial species diversity and targeted community dynamics of both lactic acid bacteria (LAB) and acetic acid bacteria (AAB) during fermentation, as was the case during cocoa bean fermentations processes carried out in the field. LAB isolates belonged to two main (GTG)(5)-PCR clusters, namely Lactobacillus plantarum and Lactobacillus fermentum, with Fructobacillus pseudofilculneus occurring occasionally; one main (GTG)(5)-PCR cluster, composed of Acetobacter pasteurianus, was found among the AAB isolates, besides minor clusters of Acetobacter ghanensis and Acetobacter senegalensis. 16S rRNA-PCR-DGGE revealed that L. plantarum and L. fermentum dominated the fermentations from day two until the end and Acetobacter was the only AAB species present at the end of the fermentations. Also, species of Tatumella and Pantoea were detected culture-independently at the beginning of the fermentations. Further, it was shown through metabolite target analyses that similar substrate consumption and metabolite production kinetics occurred in the vessels compared to spontaneous cocoa bean fermentation processes. Current drawbacks of the vessel fermentations encompassed an insufficient mixing of the cocoa pulp-bean mass and retarded yeast growth. PMID:21356451

  9. Properties of different lactic acid bacteria isolated from Apis mellifera L. bee-gut.

    PubMed

    Carina Audisio, M; Torres, María J; Sabaté, Daniela C; Ibarguren, Carolina; Apella, María C

    2011-01-20

    Eight strains belonging to Lactobacillus spp. and five to Enterococcus spp. were isolated from the gut of worker Apis mellifera L. bees. Studies based on 16S rRNA sequencing revealed that AJ5, IG9, A15 and CRL1647 strains had a 99% identity with Lactobacillus johnsonii, while SM21 showed a 99% similarity with Enterococcus faecium. L. johnsonii CRL1647, AJ5 and IG9 were high lactic acid producers (values were between 177 and 275 mM), and in vitro they inhibited different human food-borne pathogens and Paenibacillus larvae, the American foulbrood agent. This bacterium was the most sensitive to the lactic acid effect being inhibited by 44 mM of this metabolite. L. johnsonii CRL1647, AJ5 and IG9 also presented important surface properties. These cells showed between 77% and 93% of auto-aggregation. The preliminary study of the chemical nature of the aggregating factors revealed that the molecules involved in the surface of each L. johnsonii strain were quite complex; and something of a peptidic nature was mainly involved. E. faecium SM21 produced bacteriocin-like compounds with anti-Listeria effects. Furthermore, a band close to 6.0-7.5 kDA was detected by SDS-PAGE studies, and the entA, B and P structural genes were amplified by PCR reactions. For the first time, bee-gut associated L. johnsonii and E. faecium strains have been isolated, identified, cultivated and some of their functional properties reported. PMID:20116222

  10. Population dynamics and metabolite target analysis of lactic acid bacteria during laboratory fermentations of wheat and spelt sourdoughs.

    PubMed

    Van der Meulen, Roel; Scheirlinck, Ilse; Van Schoor, Ann; Huys, Geert; Vancanneyt, Marc; Vandamme, Peter; De Vuyst, Luc

    2007-08-01

    Four laboratory sourdough fermentations, initiated with wheat or spelt flour and without the addition of a starter culture, were prepared over a period of 10 days with daily back-slopping. Samples taken at all refreshment steps were used for determination of the present microbiota. Furthermore, an extensive metabolite target analysis of more than 100 different compounds was performed through a combination of various chromatographic methods including liquid chromatography-mass spectrometry and gas chromatography-mass spectrometry. The establishment of a stable microbial ecosystem occurred through a three-phase evolution within a week, as revealed by both microbiological and metabolite analyses. Strains of Lactobacillus plantarum, Lactobacillus fermentum, Lactobacillus rossiae, Lactobacillus brevis, and Lactobacillus paraplantarum were dominating some of the sourdough ecosystems. Although the heterofermentative L. fermentum was dominating one of the wheat sourdoughs, all other sourdoughs were dominated by a combination of obligate and facultative heterofermentative taxa. Strains of homofermentative species were not retrieved in the stable sourdough ecosystems. Concentrations of sugar and amino acid metabolites hardly changed during the last days of fermentation. Besides lactic acid, ethanol, and mannitol, the production of succinic acid, erythritol, and various amino acid metabolites, such as phenyllactic acid, hydroxyphenyllactic acid, and indolelactic acid, was shown during fermentation. Physiologically, they contributed to the equilibration of the redox balance. The biphasic approach of the present study allowed us to map some of the interactions taking place during sourdough fermentation and helped us to understand the fine-tuned metabolism of lactic acid bacteria, which allows them to dominate a food ecosystem. PMID:17557853

  11. Population Dynamics and Metabolite Target Analysis of Lactic Acid Bacteria during Laboratory Fermentations of Wheat and Spelt Sourdoughs?

    PubMed Central

    Van der Meulen, Roel; Scheirlinck, Ilse; Van Schoor, Ann; Huys, Geert; Vancanneyt, Marc; Vandamme, Peter; De Vuyst, Luc

    2007-01-01

    Four laboratory sourdough fermentations, initiated with wheat or spelt flour and without the addition of a starter culture, were prepared over a period of 10 days with daily back-slopping. Samples taken at all refreshment steps were used for determination of the present microbiota. Furthermore, an extensive metabolite target analysis of more than 100 different compounds was performed through a combination of various chromatographic methods including liquid chromatography-mass spectrometry and gas chromatography-mass spectrometry. The establishment of a stable microbial ecosystem occurred through a three-phase evolution within a week, as revealed by both microbiological and metabolite analyses. Strains of Lactobacillus plantarum, Lactobacillus fermentum, Lactobacillus rossiae, Lactobacillus brevis, and Lactobacillus paraplantarum were dominating some of the sourdough ecosystems. Although the heterofermentative L. fermentum was dominating one of the wheat sourdoughs, all other sourdoughs were dominated by a combination of obligate and facultative heterofermentative taxa. Strains of homofermentative species were not retrieved in the stable sourdough ecosystems. Concentrations of sugar and amino acid metabolites hardly changed during the last days of fermentation. Besides lactic acid, ethanol, and mannitol, the production of succinic acid, erythritol, and various amino acid metabolites, such as phenyllactic acid, hydroxyphenyllactic acid, and indolelactic acid, was shown during fermentation. Physiologically, they contributed to the equilibration of the redox balance. The biphasic approach of the present study allowed us to map some of the interactions taking place during sourdough fermentation and helped us to understand the fine-tuned metabolism of lactic acid bacteria, which allows them to dominate a food ecosystem. PMID:17557853

  12. Separation of lactic acid-producing bacteria from fermentation broth using a ceramic microfiltration membrane with constant permeate flow.

    PubMed

    Persson, A; Jönsson, A S; Zacchi, G

    2001-02-01

    The influence of several operating parameters on the critical flux in the separation of lactic acid-producing bacteria from fermentation broth was studied using a ceramic microfiltration membrane equipped with a permeate pump. The operating parameters studied were crossflow velocity over the membrane, bacterial cell concentration, protein concentration, and pH. The influence of the isoelectric point (IEP) of the membrane was also investigated. In the interval studied (5.3-10.8 m/s), the crossflow velocity had a marked effect on the critical flux. When the crossflow velocity was increased the critical flux also increased. The bacterial cells were retained by the membrane and the concentration of bacterial cells did not affect the critical flux in the interval studied (1.1-3.1 g/L). The critical flux decreased when the protein concentration was increased. It was found that the protein was adsorbed on the membrane surface and protein retention occurred even though the conditions were such that no filter cake was present on the membrane surface. When the pH of the medium was lowered from 6 to 5 (and then further to 4) the critical flux decreased from 76 L/m(2)h to zero at both pH 5 and pH 4. This was found to be due to the fact that the lowering in pH had affected the physiology of the bacterial cells so that the bacteria tended to adhere to the membrane and to each other. The critical flux, for wheat flour hydrolysate without particles, was much lower (28 L/m(2)h) when using a membrane with an IEP of 5.5 than the critical flux of a membrane with an IEP at pH 7 (96 L/m(2)h). This was found to be due to an increased affinity of the bacteria for the membrane with the lower IEP. PMID:11135196

  13. Application of Potential Phosphate-Solubilizing Bacteria and Organic Acids on Phosphate Solubilization from Phosphate Rock in Aerobic Rice

    PubMed Central

    Jusop, Shamshuddin; Naher, Umme Aminun; Othman, Radziah; Razi, Mohd Ismail

    2013-01-01

    A study was conducted at Universiti Putra Malaysia to determine the effect of phosphate-solubilizing bacteria (PSB) and organic acids (oxalic & malic) on phosphate (P) solubilization from phosphate rock (PR) and growth of aerobic rice. Four rates of each organic acid (0, 10, 20, and 30?mM), and PSB strain (Bacillus sp.) were applied to aerobic rice. Total bacterial populations, amount of P solubilization, P uptake, soil pH, and root morphology were determined. The results of the study showed significantly high P solubilization in PSB with organic acid treatments. Among the two organic acids, oxalic acid was found more effective compared to malic acid. Application of oxalic acid at 20?mM along with PSB16 significantly increased soluble soil P (28.39?mg kg?1), plant P uptake (0.78?P pot?1), and plant biomass (33.26?mg). Addition of organic acids with PSB and PR had no influence on soil pH during the planting period. A higher bacterial population was found in rhizosphere (8.78 log10?cfu g?1) compared to the nonrhizosphere and endosphere regions. The application of organic acids along with PSB enhanced soluble P in the soil solution, improved root growth, and increased plant biomass of aerobic rice seedlings without affecting soil pH. PMID:24288473

  14. Evidence for propagation of aerobic bacteria in particles suspended in gaseous atmospheres. [Terrestrial microorganism contamination of Jupiter atmosphere

    NASA Technical Reports Server (NTRS)

    Dimmick, R. L.; Chatigny, M. A.; Wolochow, H.; Straat, P.

    1977-01-01

    One factor involved in the possibility that airborne microbes might contaminate the Jovian atmosphere is whether microbes have the capacity to propagate in air. Prior to these studies, the evidence was that the airborne state was lethal to microbes. An aerosol of aerobic bacteria was mixed with another containing C-14-glucose, and the presence of C-14-CO2 was subsequently detected, which indicates that the airborne cells were metabolically active. In the same type of experiment, it was shown that thymidine was incorporated into the acid-insoluble fraction of samples, indicating the formation of DNA. It was also shown, both by an increase in the numbers of viable cells and a parallel increase in particle numbers, that at least two new generations of cells could occur. Evidence for propagation of anaerobic bacteria has so far been negative.

  15. Effects of a mixture of lactic acid bacteria applied as a freeze-dried or fresh culture on the fermentation of alfalfa silage.

    PubMed

    Kizilsimsek, M; Schmidt, R J; Kung, L

    2007-12-01

    Alfalfa (approximately 31% DM) was untreated or treated with a silage inoculant containing the lactic acid bacteria Lactobacillus lactis, Lactobacillus plantarum L-54, and L. plantarum Aber F1. The inoculant was added at a normal and a high dose as a freeze-dried powder that had been mixed with water just prior to application, or it was grown with nutrients the day before and added as a fresh culture. The actual application rate of lactic acid bacteria was 1.19 x 10(5) for the normal dose, 4.30 x 10(5) for the high dose, and 5.10 x 10(5) for the fresh culture. All inoculated silages showed a faster increase in the rate of lactic acid production and a decrease in the drop in pH over the first 24 h of ensiling compared with untreated silage. The effect was greatest for silage treated with the fresh culture and was supported by the fact that this treatment had numbers of lactic acid bacteria that increased faster than in other treatments. Inoculation also generally resulted in a fermentation profile that was more homolactic (more lactic acid and less acetic acid, ethanol, and NH(3)-N) than for untreated silage, but the effect was greatest for the fresh culture. Inoculation did not affect in vitro neutral detergent fiber digestion or the concentrations of neutral detergent fiber or total N in silages. The recovery of dry matter was greater in silage that was treated with a high level of the freeze-dried culture or with the fresh culture when compared with the untreated control. This study showed that application of a silage inoculant as a freeze-dried culture or as a fresh culture resulted in alfalfa silage with a more homolactic fermentation profile. The effect was greatest from addition of the fresh culture. PMID:18024762

  16. Impact of an aerobic thermophilic sequencing batch reactor on antibiotic-resistant anaerobic bacteria in swine waste.

    PubMed

    Chénier, Martin R; Juteau, Pierre

    2009-11-01

    The introduction of antibiotics to animal feed has contributed to the selection of antibiotic-resistant bacteria in concentrated animal feeding operations. The aim of this work was to characterize the impact of an aerobic thermophilic biotreatment on anaerobic antibiotic-resistant bacteria in swine waste. Despite 162- to 6,166-fold reduction in antibiotic-resistant populations enumerated in the swine waste at 25 degrees C and 37 degrees C, resistant populations remained significant (10(4) to 10(5) most probable number per milliliter) in the treated swine waste. Five resistance genes were detected before [tet(LMOS) erm(B)], and six resistance genes were detected after [tet(LMOSY) erm(B)] biotreatment. However, the biotreatment decreased the frequency of detection of resistance genes by 57%. Analysis by denaturing gradient gel electrophoresis of polymerase chain reaction-amplified 16 S ribosomal DNA (rDNA) fragments showed that the biotreatment reduced the bacterial diversity of resistant populations enumerated at 37 degrees C. Cloning and sequencing of the 16 S rDNA of these populations revealed that most clones in the treated swine waste were closely similar to some of the clones retrieved from the untreated swine waste. This study revealed that the aerobic thermophilic biotreatment developed in our laboratory does not prevent the introduction of facultatively anaerobic antibiotic-resistant bacteria and their resistance genes into agricultural ecosystems. Horizontal transfer of ecologically advantageous genes within microbial communities are likely to prevent thermophilic biotreatments from completely eliminating antibiotic-resistant bacteria and their resistance genes in animal wastes. PMID:19562247

  17. Phylogenetic analysis of nitric oxide reductase gene homologues from aerobic ammonia-oxidizing bacteria

    E-print Network

    Ward, Bess

    -oxidizing bacteria Karen L. Casciotti *,1 , Bess B. Ward Department of Geosciences, Princeton University, Princeton) are climatically important trace gases that are produced by both nitrifying and den- itrifying bacteria-oxidizing bacteria, including Nitrosomonas and Nitrosococcus species (i.e., both b- and c-Proteobacterial ammonia

  18. Quantification of the Antimicrobial Substances Produced by Lactic Acid Bacteria used as an Intervention to Inhibit Escherichia coli O157:H7 and Salmonella in vitro and on Fresh Spinach (Spinacia oleracea)

    E-print Network

    Calix Lara, Thelma

    2012-02-14

    The metabolic activity of bacterial microorganisms may influence the growth and metabolic activities of other microbes that are present in any specific niche. Lactic acid bacteria (LAB) are antagonistic to some microbial pathogens by the metabolic...

  19. Nitric Oxide (NO) and Lactic Acid Bacteria-Contributions to Health, Food Quality, and Safety

    Microsoft Academic Search

    Aynur Gül Karahan; M. Lütfü Çakmakçi; Buket Cicioglu-Aridogan; Arzu Kart-Gündogdu

    2005-01-01

    In this article, the effects of nitric oxide (NO) and nitric oxide producer bacteria on food quality, safety, and human health care high lighted. NO, which was previously recognized as a toxic gas, has attracted attention in the last two decades due to its vital role in many physiological processes of animals and plants. Particularly, it is important to note

  20. Recent investigations and updated criteria for the assessment of antibiotic resistance in food lactic acid bacteria

    Microsoft Academic Search

    Francesca Clementi; Lucia Aquilanti

    The worldwide use, and misuse, of antibiotics for about sixty years in the so-called antibiotic era, has been estimated in some one to ten million tons, a relevant part of which destined for non-therapeutic purposes such as growth promoting treatments for livestock or crop protection. As highly adaptable organisms, bacteria have reacted to this dramatic change in their environment by

  1. The Bacillus subtilis and Lactic Acid Bacteria Probiotics Influences Intestinal Mucin Gene Expression, Histomorphology and Growth Performance in Broilers.

    PubMed

    Aliakbarpour, H R; Chamani, M; Rahimi, G; Sadeghi, A A; Qujeq, D

    2012-09-01

    The aim of the present study was to evaluate the effect of commercial monostrain and multistrain probiotics in diets on growth performance, intestinal morphology and mucin gene (MUC2) expression in broiler chicks. Three hundred seventy-eight 1-d-old male Arian broiler chicks were allocated in 3 experimental groups for 6 wk. The birds were fed on a corn-soybean based diet and depending on the addition were labeled as follows: control-unsupplemented (C), birds supplemented with Bacillus subtilis (BS) and lactic acid bacteria (LAB) based probiotics. Each treatment had 6 replicates of 21 broilers each. Treatment effects on body weight, feed intake, feed conversion ratio and biomarkers such as intestinal goblet cell density, villus length, villus width, and mucin gene expression were determined. Total feed intake did not differ significantly between control birds and those fed a diet with probiotics (p>0.05). However, significant differences in growth performance were found. Final body weight at 42 d of age was higher in birds fed a diet with probiotics compared to those fed a diet without probiotic (p<0.05). Inclusion of Bacillus subtilis based probiotic in the diets also significantly affected feed conversion rate (FCR) compared with control birds (p<0.05). No differences in growth performance were observed in birds fed different types of probiotic supplemented diets. Inclusion of lactic acid bacteria based probiotic in the diets significantly increased goblet cell number and villus length (p<0.05). Furthermore, diets with Bacillus subtilis based probiotics significantly increased gene expression (p<0.05), with higher intestinal MUC2 mRNA in birds fed diet with probiotics compared to those fed the control diet. In BS and LAB probiotic fed chicks, higher growth performance may be related to higher expression of the MUC2 gene in goblet cells and/or morphological change of small intestinal tract. The higher synthesis of the mucin gene after probiotic administration may positively affect bacterial interactions in the intestinal digestive tract, intestinal mucosal cell proliferation and consequently efficient nutrient absorption. PMID:25049692

  2. Prebiotic Content of Bread Prepared with Flour from Immature Wheat Grain and Selected Dextran-Producing Lactic Acid Bacteria

    PubMed Central

    Ventorino, Valeria; Cavella, Silvana; Fagnano, Massimo; Brugno, Rachele

    2013-01-01

    In the last few years the need to produce food with added value has fueled the search for new ingredients and health-promoting compounds. In particular, to improve the quality of bakery products with distinct nutritional properties, the identification of new raw materials, appropriate technologies, and specific microbial strains is necessary. In this study, different doughs were prepared, with 10% and 20% flour from immature wheat grain blended with type “0 America” wheat flour. Immature flour was obtained from durum wheat grains harvested 1 to 2 weeks after anthesis. Doughs were obtained by both the straight-dough and sourdough processes. Two selected exopolysaccharide-producing strains of lactic acid bacteria (LAB), Leuconostoc lactis A95 and Lactobacillus curvatus 69B2, were used as starters. Immature flour contained 2.21 g/100 g (dry weight) of fructo-oligosaccharides. Twenty percent immature flour in dough resulted in a shorter leavening time (4.23 ± 0.03 h) than with the control and dough with 10% immature flour. The total titratable acidity of sourdough with 20% immature flour was higher (12.75 ± 0.15 ml 0.1 N NaOH) than in the control and sourdough with 10% immature wheat flour (9.20 ml 0.1 N NaOH). Molecular analysis showed that all samples contained three LAB species identified as L. lactis, L. curvatus, and Pediococcus acidilactici. A larger amount of exopolysaccharide was found in sourdough obtained with 20% immature flour (5.33 ± 0.032 g/kg), positively influencing the exopolysaccharide content of the bread prepared by the sourdough process (1.70 ± 0.03 g/kg). The addition of 20% immature flour also led to a greater presence of fructo-oligosaccharides in the bread (900 mg/100 g dry weight), which improved its nutritional characteristics. While bread volume decreased as the concentration of immature wheat flour increased, its mechanical characteristics (stress at a strain of 30%) were the same in all samples obtained with different percentages of fructo-oligosaccharides. These data support the use of immature wheat grain flour, and exopolysaccaride-producing lactic acid bacteria in formulating functional prebiotic baked goods whose nutritional value can be suitably improved. PMID:23584774

  3. Bioaugmentation treatment of municipal wastewater with heterotrophic-aerobic nitrogen removal bacteria in a pilot-scale SBR.

    PubMed

    Chen, Qian; Ni, Jinren; Ma, Tao; Liu, Tang; Zheng, Maosheng

    2015-05-01

    PCN bacteria capable of heterotrophic-aerobic nitrogen removal was successfully applied for bioaugmented treatment of municipal wastewater in a pilot-scale SBR. At an appropriate COD/N ratio of 8, the bioaugmentation system exhibited stable and excellent carbon and nutrients removal, the averaged effluent concentrations of COD, NH4(+)-N, TN and TP were 20.6, 0.69, 14.1 and 0.40mg/L, respectively, which could meet the first class requirement of the National Municipal Wastewater Discharge Standards of China (COD<50mg/L, TN<15mg/L, TP<0.5mg/L). Clone library and real-time PCR analysis revealed that the introduced bacteria greatly improved the structure of original microbial community and facilitated their aerobic nutrients removal capacities. The proposed emerging technology was shown to be an alternative technology to establish new wastewater treatment systems and upgrade or retrofit conventional systems from secondary-level to tertiary-level. PMID:25710680

  4. 10-oxo-12(Z)-octadecenoic acid, a linoleic acid metabolite produced by gut lactic acid bacteria, potently activates PPAR? and stimulates adipogenesis.

    PubMed

    Goto, Tsuyoshi; Kim, Young-Il; Furuzono, Tomoya; Takahashi, Nobuyuki; Yamakuni, Kanae; Yang, Ha-Eun; Li, Yongjia; Ohue, Ryuji; Nomura, Wataru; Sugawara, Tatsuya; Yu, Rina; Kitamura, Nahoko; Park, Si-Bum; Kishino, Shigenobu; Ogawa, Jun; Kawada, Teruo

    2015-04-17

    Our previous study has shown that gut lactic acid bacteria generate various kinds of fatty acids from polyunsaturated fatty acids such as linoleic acid (LA). In this study, we investigated the effects of LA and LA-derived fatty acids on the activation of peroxisome proliferator-activated receptors (PPARs) which regulate whole-body energy metabolism. None of the fatty acids activated PPAR?, whereas almost all activated PPAR? in luciferase assays. Two fatty acids potently activated PPAR?, a master regulator of adipocyte differentiation, with 10-oxo-12(Z)-octadecenoic acid (KetoA) having the most potency. In 3T3-L1 cells, KetoA induced adipocyte differentiation via the activation of PPAR?, and increased adiponectin production and insulin-stimulated glucose uptake. These findings suggest that fatty acids, including KetoA, generated in gut by lactic acid bacteria may be involved in the regulation of host energy metabolism. PMID:25749343

  5. Isolation and Identification of Lactic Acid Bacteria Isolated from a Traditional Jeotgal Product in Korea

    NASA Astrophysics Data System (ADS)

    Cho, Gyu Sung; Do, Hyung Ki

    2006-06-01

    Seventeen lactic acid bacterial strains (LAB) were isolated using MRS agar medium from Jeotgal, a Korean fermented food, purchased at the Jukdo market of Pohang. To identify the strains isolated, they were tested by examining their cell morphologies, gram-staining, catalase activity, arginine hydrolase activity, D-L lactate form and carbohydrate fermentation. According to the phenotypic characteristics, three strains were tent atively identified as Lactobacillus spp., ten were Enterococcus spp. (or Streptococcus spp., or Pediococcus spp.) and the rest were Leuconostoc spp. (or Weissella spp.). Five strains among 17 were chosen by preliminary bacteriocin activity test. Four bacterial strains which inhibited both indicator microorganisms were identified by 16S rRNA sequencing. The results are as follows; Leuconostoc mesenteroides (HK 4), Leuconostoc mesenteroides (HK 5), Leuconostoc mesenteroides(HK 11), Streptococcus salivarius(HK 8). In order to check LAB which are showing a high survival rate in gut, we investigated three strains inhibiting both indicator microorganisms in artificial gastric acid and bile juice -all except HK8. The three strains mentioned above grew in extreme low acid conditions.

  6. Characterization of lactic acid bacteria isolated from a Thai low-salt fermented fish product and the role of garlic as substrate for fermentation

    Microsoft Academic Search

    Christine Paludan-Müller; Hans Henrik Huss; Lone Gram

    1999-01-01

    Lactic acid bacteria (LAB) isolated from raw materials (fish, rice, garlic and banana leaves) and processed som-fak (a Thai low-salt fermented fish product) were characterized by API 50-CH and other phenotypic criteria. Lactococcus lactis subsp. lactis and Leuconostoc citreum were specifically associated with fish fillet and minced fish, Lactobacillus paracasei subsp. paracasei with boiled rice and Weisella confusa with garlic

  7. Isolation and characterization of lactic acid bacteria from Yan-dong-gua (fermented wax gourd), a traditional fermented food in Taiwan

    Microsoft Academic Search

    Wei-Tse Lan; Yi-sheng Chen; Fujitoshi Yanagida

    2009-01-01

    Yan-dong-gua (fermented wax gourd; a traditional fermented food in Taiwan) samples were collected at five time intervals from a fixed fermenting bucket. Eighty-five cultures of lactic acid bacteria (LAB) were isolated from Yan-dong-gua samples, and the isolates were divided into classes by phenotype and then groups by restriction fragment length polymorphism analysis and sequencing of 16S ribosomal DNA. Phenotypic and

  8. Enhancement of survival of probiotic and non-probiotic lactic acid bacteria by yeasts in fermented milk under non-refrigerated conditions

    Microsoft Academic Search

    Shao-Quan Liu; Marlene Tsao

    2009-01-01

    The effects of yeasts on the survival of probiotic and non-probiotic lactic acid bacteria (LAB) were studied in fermented milk under non-refrigerated conditions (30 °C) with a view to develop ambient-stable fermented milk with live LAB. Five yeasts tested (Saccharomyces bayanus, Williopsis saturnus var. saturnus, Yarrowia lipolytica, Candida kefyr and Kluyveromyces marxianus) enhanced the survival of Lactobacillus bulgaricus (but not Streptococcus

  9. Application of Native Lactic Acid Bacteria (LAB) for Fermentative Recovery of Lipids and Proteins from Fish Processing Wastes: Bioactivities of Fermentation Products

    Microsoft Academic Search

    Amit Kumar Rai; R. Jini; H. C. Swapna; N. M. Sachindra; N. Bhaskar; V. Baskaran

    2011-01-01

    Fermentation using native lactic acid bacteria (LAB) was evaluated for its effectiveness in recovering lipids and proteins simultaneously from freshwater fish visceral waste (FVW). Five different LAB isolated from fish processing waste were employed in a fermentation process that involved 10% (w\\/w) glucose, 2% (w\\/w) NaCl, and 10% (v\\/w) LAB. Cultures evaluated included four native isolates (Pediococcus acidilactici NCIM5368, Enterococcus

  10. Development of oligonucleotide primers from the 16S-23S rRNA intergenic sequences for identifying different dairy and probiotic lactic acid bacteria by PCR

    Microsoft Academic Search

    Anu Tilsala-Timisjärvi; Tapani Alatossava

    1997-01-01

    Spacer regions between the 16S and 23S rRNA genes of different dairy and probiotic lactic acid bacteria were amplified by the polymerase chain reaction (PCR) with conserved primers and the nucleotide sequences of these spacer regions were determined. Amplification\\/oligonucleotide primer pairs were designed for Lactobacillus paracasei, Lactobacillus rhamnosus, Lactobacillus delbrueckii, Lactobacillus acidophilus, Lactobacillus helveticus and Streptococcus thermophilus based on the

  11. Molecular diversity of Lactobacillus spp. and other lactic acid bacteria in the human intestine as determined by specific amplification of 16S ribosomal DNA

    Microsoft Academic Search

    G. H. J. Heilig; Erwin G. Zoetendal; Elaine E. Vaughan; Philippe Marteau; Antoon D. L. Akkermans; Vos de W. M

    2002-01-01

    A Lactobacillus group-specific PCR primer, S-G-Lab-0677-a-A-17, was developed to selectively amplify 16S ribosomal DNA (rDNA) from lactobacilli and related lactic acid bacteria, including members of the genera Leuconostoc, Pediococcus, and Weissella. Amplicons generated by PCR from a variety of gastrointestinal (GI) tract samples, including those originating from feces and cecum, resulted predominantly in Lactobacillus-like sequences, of which ca. 28 ere

  12. Effect of acid lactic bacteria isolated from faeces of healthy dogs on growth parameters and aflatoxin B 1 production by Aspergillus species in vitro

    Microsoft Academic Search

    María Guillermina Fernández-Juri; Julián A. Muzzolón; Ana María Dalcero; Carina E. Magnoli

    The aim of the present study was to evaluate the inhibitory effect of Enterococcus faecium and Lactococcus lactis subsp. lactis isolated from faeces of healthy dogs on (i) lag phase, (ii) growth rate, and (iii) aflatoxin B1 production by Aspergillus section Flavi on in vitro assays. Thirteen lactic acid bacteria (LAB) isolates were used as antagonist microorganisms. Antagonistic activity\\u000a was

  13. The effects of lactic acid bacteria and mannan oligosaccharide, with or without fumaric acid, on chicken performance, slaughter yield and digestive tract microflora

    Microsoft Academic Search

    F. Brzóska; S. Buluchevskij; K. Stecka; B. ?liwi?ski

    2007-01-01

    In an experiment performed on 600 ROSS broilers the effect of dietary lactic acid bacteria (LAB), mannan oligosaccharide (MOS) without (LAB, MOS) or with fumaric acid (LAB, MOS, FUA) in comparison with antibiotic-supplemented birds (ANT) on performance, mortality, carcass yield, and microflora spectrum of the digestive tract was studied. The body weight of birds at 42 days was 2.2, 2.5,

  14. Effect of dissolved oxygen on redox potential and milk acidification by lactic acid bacteria isolated from a DL-starter culture.

    PubMed

    Larsen, Nadja; Werner, Birgit Brøsted; Vogensen, Finn Kvist; Jespersen, Lene

    2015-03-01

    Milk acidification by DL-starter cultures [cultures containing Lactococcus lactis diacetylactis (D) and Leuconostoc (L) species] depends on the oxidation-reduction (redox) potential in milk; however, the mechanisms behind this effect are not completely clear. The objective of this study was to investigate the effect of dissolved oxygen on acidification kinetics and redox potential during milk fermentation by lactic acid bacteria (LAB). Fermentations were conducted by single strains isolated from mixed DL-starter culture, including Lactococcus lactis ssp. lactis, Lactococcus lactis ssp. cremoris, and Leuconostoc mesenteroides ssp. cremoris, by the DL-starter culture, and by the type strains. High and low levels of oxygen were produced by flushing milk with oxygen or nitrogen, respectively. The kinetics of milk acidification was characterized by the maximum rate and time of acidification (V(a)max and T(a)max), the maximum rate and time of reduction (V(r)max and T(r)max), the minimum redox potential (Eh7 final), and time of reaching Eh7 final (T(r)final). Variations in kinetic parameters were observed at both the species and strain levels. Two of the Lc. lactis ssp. lactis strains were not able to lower redox potential to negative values. Kinetic parameters of the DL-starter culture were comparable with the best acidifying and reducing strains, indicating their additive effects. Acidification curves were mostly diauxic at all oxygen levels, displaying 2 maxima of acidification rate: before (aerobic maximum) and after (anaerobic maximum) oxygen depletion. The redox potential decreased concurrently with oxygen consumption and continued to decrease at slower rate until reaching the final values, indicating involvement of both oxygen and microbiological activity in the redox state of milk. Oxygen flushing had a negative effect on reduction and acidification capacity of tested LAB. Reduction was significantly delayed at high initial oxygen, exhibiting longer T(r)max, T(r)final, or both. Concurrently, anaerobic acidification rate maximum V(a)max was decreased and T(a)max was extended. Fermentation kinetics in nitrogen-flushed milk was not statistically different from that in untreated milk except for Lc. lactis ssp. lactis CHCC D2, which showed faster reduction time after nitrogen flushing. This study clarifies the relationship between the redox state in milk and acidification kinetics of the predominant subspecies in DL-starter cultures. This knowledge is important for dairies to ensure optimized, fast, and controlled milk fermentations, leading to greater standardization of dairy products. PMID:25597975

  15. Characterization and Determination of Origin of Lactic Acid Bacteria from a Sorghum-Based Fermented Weaning Food by Analysis of Soluble Proteins and Amplified Fragment Length Polymorphism Fingerprinting

    PubMed Central

    Kunene, Nokuthula F.; Geornaras, Ifigenia; von Holy, Alexander; Hastings, John W.

    2000-01-01

    The group that includes the lactic acid bacteria is one of the most diverse groups of bacteria known, and these organisms have been characterized extensively by using different techniques. In this study, 180 lactic acid bacterial strains isolated from sorghum powder (44 strains) and from corresponding fermented (93 strains) and cooked fermented (43 strains) porridge samples that were prepared in 15 households were characterized by using biochemical and physiological methods, as well as by analyzing the electrophoretic profiles of total soluble proteins. A total of 58 of the 180 strains were Lactobacillus plantarum strains, 47 were Leuconostoc mesenteroides strains, 25 were Lactobacillus sake-Lactobacillus curvatus strains, 17 were Pediococcus pentosaceus strains, 13 were Pediococcus acidilactici strains, and 7 were Lactococcus lactis strains. L. plantarum and L. mesenteroides strains were the dominant strains during the fermentation process and were recovered from 87 and 73% of the households, respectively. The potential origins of these groups of lactic acid bacteria were assessed by amplified fragment length polymorphism fingerprint analysis. PMID:10698775

  16. Phylogenetic Diversity of Lactic Acid Bacteria Associated with Paddy Rice Silage as Determined by 16S Ribosomal DNA Analysis

    PubMed Central

    Ennahar, Saïd; Cai, Yimin; Fujita, Yasuhito

    2003-01-01

    A total of 161 low-G+C-content gram-positive bacteria isolated from whole-crop paddy rice silage were classified and subjected to phenotypic and genetic analyses. Based on morphological and biochemical characters, these presumptive lactic acid bacterium (LAB) isolates were divided into 10 groups that included members of the genera Enterococcus, Lactobacillus, Lactococcus, Leuconostoc, Pediococcus, and Weissella. Analysis of the 16S ribosomal DNA (rDNA) was used to confirm the presence of the predominant groups indicated by phenotypic analysis and to determine the phylogenetic affiliation of representative strains. The virtually complete 16S rRNA gene was PCR amplified and sequenced. The sequences from the various LAB isolates showed high degrees of similarity to those of the GenBank reference strains (between 98.7 and 99.8%). Phylogenetic trees based on the 16S rDNA sequence displayed high consistency, with nodes supported by high bootstrap values. With the exception of one species, the genetic data was in agreement with the phenotypic identification. The prevalent LAB, predominantly homofermentative (66%), consisted of Lactobacillus plantarum (24%), Lactococcus lactis (22%), Leuconostoc pseudomesenteroides (20%), Pediococcus acidilactici (11%), Lactobacillus brevis (11%), Enterococcus faecalis (7%), Weissella kimchii (3%), and Pediococcus pentosaceus (2%). The present study, the first to fully document rice-associated LAB, showed a very diverse community of LAB with a relatively high number of species involved in the fermentation process of paddy rice silage. The comprehensive 16S rDNA-based approach to describing LAB community structure was valuable in revealing the large diversity of bacteria inhabiting paddy rice silage and enabling the future design of appropriate inoculants aimed at improving its fermentation quality. PMID:12514026

  17. Enhancement of the immune response against Salmonella infection of mice by heat-killed multispecies combinations of lactic acid bacteria.

    PubMed

    Chen, Chih-Yuan; Tsen, Hau-Yang; Lin, Chun-Li; Lin, Chien-Ku; Chuang, Li-Tsen; Chen, Chin-Shuh; Chiang, Yu-Cheng

    2013-11-01

    Heat-killed lactic acid bacteria (LAB) has advantages over live LAB in that it has a long shelf-life and is therefore easy to store and transport. From four LAB strains selected by immunomodulatory activity and adherent properties, we prepared the heat-killed multispecies combination of LAB (MLAB) and the cell walls from MLAB under two conditions (100 °C for 30 min and 121 °C for 15 min). Different effects on the adherent properties of these four LAB strains were observed, depending on the heating conditions. With mouse macrophage cells, the two heat-killed MLABs (HMLABs) showed significantly higher induction activities on the production of interleukin 12 (IL-12) than their individual strains did. Heat-killed MLABs and cell-wall preparations were able to reduce the Salmonella invasion of Caco-2 and mouse macrophage cells. Feeding mice with HMLAB could inhibit the Salmonella invasion of mice significantly. For these mice, the expression level of pro-inflammatory cytokines, such as TNF-? and IL-6, in mouse serum was reduced while that of the anti-inflammatory cytokine, i.e. IL-10, was enhanced. The HMLABs developed in this study showed higher protective effect against Salmonella invasion either of Caco-2 cells or of mice, relative to the heat-killed lactobacilli, which consisted of Lactobacillus acidophilus strains selected at random. In conclusion, the HMLABs were potentially useful for the protection of mice against Salmonella infection and the induced inflammation. PMID:24000228

  18. Modulation of peanut-induced allergic immune responses by oral lactic acid bacteria-based vaccines in mice.

    PubMed

    Ren, Chengcheng; Zhang, Qiuxiang; Wang, Gang; Ai, Chunqing; Hu, Mengsha; Liu, Xiaoming; Tian, Fengwei; Zhao, Jianxin; Chen, Yongquan; Wang, Miao; Zhang, Hao; Chen, Wei

    2014-01-01

    Peanut allergy (PNA) has becoming a non-negligible health concern worldwide. Thus far, allergen-specific immunotherapy aimed at inducing mucosal tolerance has widely been regarded as a major management strategy for PNA. The safety profiles and the intrinsic probiotic properties of lactic acid bacteria (LAB) render them attractive delivery vehicles for mucosal vaccines. In the present study, we exploited genetically modified Lactococcus lactis to produce peanut allergen Ara h 2 via different protein-targeting systems and their immunomodulatory potency for allergic immune responses in mice were investigated. By comparison with the strain expressing the cytoplasmic form of Ara h 2 (LL1), the strains expressing the secreted and anchored forms of Ara h 2 (LL2 and LL3) were more potent in redirecting a Th2-polarized to a non-allergic Th1 immune responses. Induction of SIgA and regulatory T cells were also observed at the local levels by orally administration of recombinant L. lactis. Our results indicate that allergen-producing L. lactis strains modulated allergic immune responses and may be developed as promising mucosal vaccines for managing allergic diseases. PMID:24770368

  19. Mitogenic response and probiotic characteristics of lactic acid bacteria isolated from indigenously pickled vegetables and fermented beverages.

    PubMed

    Kumar, Mukesh; Ghosh, Moushumi; Ganguli, Abhijit

    2012-02-01

    Lactic acid bacteria from indigenous pickled vegetables and fermented beverages (fermented rice and Madhuca longifolia flowers) were isolated and investigated for their functional characteristics in vitro as potential new probiotic strains. Four isolates (all Lactobacillus spp.) selected on the basis of high tolerance to bile (0.2%) were identified by standard and molecular methods (16S rDNA) as L. helveticus, L. casei, L. delbrueckii and L. bulgaricus from pickled vegetables and fermented beverages respectively. These selected strains had antibiotic resistance, tolerance to artificial gastric juice and phenol (0.4%), enzymatic profile, and antagonistic activity against enteric pathogens (Enterobacter sakazakii, Salmonella typhimurium, Shigella flexneri 2a, Listeria monocytogenes, Yersinia enterocolitica and Aeromonas hydrophila). All strains survived well in artificial gastric juice at low pH (3.0) values for 4 h, possessed bile salt hydrolase activity and were susceptible to most antibiotics including vancomycin. Additionally, the isolates exhibited high tolerance to phenol, high cell surface hydrophobicity (>60%) and induced proliferation of murine splenocytes. All the four strains of present study suppressed the Con A-stimulated proliferation of the mouse spleen cells, although L. casei had the strongest suppressive effect. The results of this study suggest a potential application of the strains (following human clinical trials), for developing probiotic foods. PMID:22806866

  20. Screening of Indigenous Oxalate Degrading Lactic Acid Bacteria from Human Faeces and South Indian Fermented Foods: Assessment of Probiotic Potential

    PubMed Central

    Kavitha, Murugan; Selvi, M. S.; Selvam, Govindan Sadasivam

    2014-01-01

    Lactic acid bacteria (LAB) have the potential to degrade intestinal oxalate and this is increasingly being studied as a promising probiotic solution to manage kidney stone disease. In this study, oxalate degrading LAB were isolated from human faeces and south Indian fermented foods, subsequently assessed for potential probiotic property in vitro and in vivo. Based on preliminary characteristics, 251 out of 673 bacterial isolates were identified as LAB. A total of 17 strains were found to degrade oxalate significantly between 40.38% and 62.90% and were subjected to acid and bile tolerance test. Among them, nine strains exhibited considerable tolerance up to pH 3.0 and at 0.3% bile. These were identified as Lactobacillus fermentum and Lactobacillus salivarius using 16S rDNA sequencing. Three strains, Lactobacillus fermentum TY5, Lactobacillus fermentum AB1, and Lactobacillus salivarius AB11, exhibited good adhesion to HT-29 cells and strong antimicrobial activity. They also conferred resistance to kanamycin, rifampicin, and ampicillin, but were sensitive to chloramphenicol and erythromycin. The faecal recovery rate of these strains was observed as 15.16% (TY5), 6.71% (AB1), and 9.3% (AB11) which indicates the colonization ability. In conclusion, three efficient oxalate degrading LAB were identified and their safety assessments suggest that they may serve as good probiotic candidates for preventing hyperoxaluria. PMID:24723820

  1. Acid induced gelation of soymilk, comparison between gels prepared with lactic acid bacteria and glucono-?-lactone.

    PubMed

    Grygorczyk, A; Corredig, M

    2013-12-01

    The objective of this work was to compare the gelation of soymilk particles induced by the acidification of a commercial starter culture with that resulting by addition of glucono-?-lactone (GDL). Structure formation was followed using rheology, and the microstructure was observed by confocal microscopy. Acidification of lactic acid bacteria resulted in a higher gelation pH (pH 6.29±0.05) compared to that of a gel induced by GDL (pH 5.9±0.04). This difference was attributed to the longer time available for rearrangements of the soymilk particles in soymilk with starter cultures compared to the fast acidification by GDL. In spite of the earlier gelation pH, there were no observed differences in the final gel stiffness measured at pH 5.1, the value of tan ?, the frequency dependence and the linear viscoelastic range of the gels measured at the final pH. Microstructural observations also showed a similar protein network structure. PMID:23870883

  2. Identification of Immunopotentiating Lactic Acid Bacteria that Induce Antibody Production by in vitro Stimulated Human Peripheral Blood Mononuclear Cells

    PubMed Central

    YAMASHITA, Makiko; HITAKA, Akira; FUJINO, Himiko; MATSUMOTO, Takashi; HASEGAWA, Takanori; MORIMATSU, Fumiki; FUJIKI, Tsukasa; KATAKURA, Yoshinori

    2012-01-01

    L-leucyl-L-leucine methyl ester (LLME) is known to remove lysosome-rich cells from human peripheral blood mononuclear cells (PBMCs). To evaluate the immunopotentiating ability of lactic acid bacteria (LAB), we adopted the in vitro stimulation protocol of LLME-treated PBMCs as a model assay system and monitored the level of antibody produced by stimulated PBMCs. The results indicated that several LAB strains have immunopotentiating ability against PBMCs, as evidenced by the enhanced antibody production and increased number of antigen-specific B cells. Next, we identified T cells as the direct target cells of the immunopotentiating LAB strain L32, suggesting that L32 induced antibody production by PBMCs through T-cell activation. Finally, we tested the immunopotentiating ability of ligands for Toll-like receptor 2 (TLR2), which is known to mediate the LAB signal, and observed that both L32 and one of the TLR2 ligands, LTA-BS, induced antigen-specific antibody production by in vitro stimulated PBMC. This suggests that L32 and LTA-BS can be used as an adjuvant for stimulating immune reaction in PBMCs. PMID:24936344

  3. Identification of Immunopotentiating Lactic Acid Bacteria that Induce Antibody Production by in vitro Stimulated Human Peripheral Blood Mononuclear Cells.

    PubMed

    Yamashita, Makiko; Hitaka, Akira; Fujino, Himiko; Matsumoto, Takashi; Hasegawa, Takanori; Morimatsu, Fumiki; Fujiki, Tsukasa; Katakura, Yoshinori

    2012-01-01

    L-leucyl-L-leucine methyl ester (LLME) is known to remove lysosome-rich cells from human peripheral blood mononuclear cells (PBMCs). To evaluate the immunopotentiating ability of lactic acid bacteria (LAB), we adopted the in vitro stimulation protocol of LLME-treated PBMCs as a model assay system and monitored the level of antibody produced by stimulated PBMCs. The results indicated that several LAB strains have immunopotentiating ability against PBMCs, as evidenced by the enhanced antibody production and increased number of antigen-specific B cells. Next, we identified T cells as the direct target cells of the immunopotentiating LAB strain L32, suggesting that L32 induced antibody production by PBMCs through T-cell activation. Finally, we tested the immunopotentiating ability of ligands for Toll-like receptor 2 (TLR2), which is known to mediate the LAB signal, and observed that both L32 and one of the TLR2 ligands, LTA-BS, induced antigen-specific antibody production by in vitro stimulated PBMC. This suggests that L32 and LTA-BS can be used as an adjuvant for stimulating immune reaction in PBMCs. PMID:24936344

  4. Improvement of Experimentally Induced Hepatic and Renal Disorders in Rats using Lactic Acid Bacteria-fermented Soybean Extract (Biofermentics™)

    PubMed Central

    Suzuki, Momoyo; Mizutani, Takeo; Susa, Nobuyuki

    2009-01-01

    The effects of lactic acid bacteria-fermented soybean extract (Biofermentics™; BF) on experimental models of hepatic and renal disorders were investigated in vivo and in vitro. In rat, hepatitis induced by feeding of deoxycholic acid (DCA, 0.5 wt/wt, n = 6) or intraperitoneal injection of d-galactosamine (GMN, 500 mg/body wt, n = 6), the increase in serum AST (aspartate aminotransferase) and ALT (alanine aminotransferase) levels were inhibited significantly (P < 0.05) by feeding a diet containing 5% dried BF. Moreover, the BF-administered rat group showed lower concentrations of blood urea nitrogen and a larger amount of urine as compared with values in the control group. Pretreatment of primary cell cultures of rat hepatic and renal cells with BF prior to exposure to dichromate (K2Cr2O7) resulted in a marked decrease of dichromate-induced cytotoxicity as evaluated by the leakage of lactate dehydrogenase The levels of dichromate-induced lipid peroxidation, as monitored by malondialdehyde formation, were also reduced by pretreatment of hepatocytes with BF. These results suggest that BF may play a role in hepatic and renal disorders, and may be useful for maintaining health in humans as well. PMID:18955265

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

    PubMed Central

    Kuwaki, Shinsuke; Nakajima, Nobuyoshi; Tanaka, Hidehiko; Ishihara, Kohji

    2012-01-01

    A plant-based paste fermented by lactic acid bacteria and yeast (fermented paste) was made from various plant materials. The paste was made of fermented food by applying traditional food-preservation techniques, that is, fermentation and sugaring. The fermented paste contained major nutrients (carbohydrates, proteins, and lipids), 18 kinds of amino acids, and vitamins (vitamin A, B1, B2, B6, B12, E, K, niacin, biotin, pantothenic acid, and folic acid). It contained five kinds of organic acids, and a large amount of dietary fiber and plant phytochemicals. Sucrose from brown sugar, used as a material, was completely resolved into glucose and fructose. Some physiological functions of the fermented paste were examined in vitro. It was demonstrated that the paste possessed antioxidant, antihypertensive, antibacterial, anti-inflammatory, anti-allergy and anti-tyrosinase activities in vitro. It was thought that the fermented paste would be a helpful functional food with various nutrients to help prevent lifestyle diseases. PMID:25114554

  6. Inventory of non starter lactic acid bacteria from ripened Parmigiano Reggiano cheese as assessed by a culture dependent multiphasic approach.

    PubMed

    Solieri, Lisa; Bianchi, Aldo; Giudici, Paolo

    2012-06-01

    The objective of this study was to investigate microbial species diversity and strain complexity of the cultivable non starter lactic acid bacteria (NSLAB) occurring in 31 ripened Parmigiano Reggiano (PR) cheeses. Dereplication of 127 lactobacilli isolates by (GTG)(5)-PCR fingerprinting yielded a total of 51 genotypes. Phylogenetic relatedness of all the genotypes with known Lactobacillus species was determined by a novel combined amplified 16S rDNA restriction analysis (16S-ARDRA), species-specific PCR assays and 16S rRNA gene sequencing. The species Lactobacillus rhamnosus and Lactobacillus paracasei comprise the largest portions of the cultivable NSLAB community in PR cheese, with an inter-individual diversity ranging from one to four dominant genotypes per sample. Lactobacillus casei, Lactobacillus harbinensis and Lactobacillus fermentum species were also detected at low frequency. The data showed differences in cultivable NSLAB population, with an overall decrease in diversity and complexity from early to advanced stages of ripening. Finally the de-replicated collection of genotypes resulting from this work is the bases for further functional screening. PMID:22626626

  7. Microcultures of lactic acid bacteria: characterization and selection of strains, optimization of nutrients and gallic acid concentration.

    PubMed

    Guzmán-López, Oswaldo; Loera, Octavio; Parada, José Luis; Castillo-Morales, Alberto; Martínez-Ramírez, Cándida; Augur, Christopher; Gaime-Perraud, Isabelle; Saucedo-Castañeda, Gerardo

    2009-01-01

    Eighteen lactic acid bacteria (LAB) strains, isolated from coffee pulp silages were characterized according to both growth and gallic acid (GA) consumption. Prussian blue method was adapted to 96-well microplates to quantify GA in LAB microcultures. Normalized data of growth and GA consumption were used to characterize strains into four phenotypes. A number of 5 LAB strains showed more than 60% of tolerance to GA at 2 g/l; whereas at 10 g/l GA growth inhibition was detected to a different extent depending on each strain, although GA consumption was observed in seven studied strains (>60%). Lactobacillus plantarum L-08 was selected for further studies based on its capacity to degrade GA at 10 g/l (97%). MRS broth and GA concentrations were varied to study the effect on growth of LAB. Cell density and growth rate were optimized by response surface methodology and kinetic analysis. Maximum growth was attained after 7.5 h of cultivation, with a dilution factor of 1-1/2 and a GA concentration between 0.625 and 2.5 g/l. Results indicated that the main factor affecting LAB growth was GA concentration. The main contribution of this study was to propose a novel adaptation of a methodology to characterize and select LAB strains with detoxifying potential of simple phenolics based on GA consumption and tolerance. In addition, the methodology presented in this study integrated the well-known RSM with an experimental design based on successive dilutions. PMID:18800233

  8. Microbial Quality and Direct PCR Identification of Lactic Acid Bacteria and Nonpathogenic Staphylococci from Artisanal Low-Acid Sausages

    PubMed Central

    Aymerich, T.; Martín, B.; Garriga, M.; Hugas, M.

    2003-01-01

    Detection of six species of lactic acid bacteria and six species of gram-positive catalase-positive cocci from low-acid fermented sausages (fuets and chorizos) was assessed by species-specific PCR. Without enrichment, Lactobacillus sakei and Lactobacillus curvatus were detected in 11.8% of the samples, and Lactobacillus plantarum and Staphylococcus xylosus were detected in 17.6%. Enriched samples allowed the detection of L. sakei and S. xylosus in all of the samples (100%) and of Enterococcus faecium in 11.8% of the sausages. The percentages of L. curvatus, L. plantarum, Staphylococcus carnosus, and Staphylococcus epidermidis varied depending on the sausage type. L. curvatus was detected in 80% of fuets and in 57% of chorizos. L. plantarum was found in 50% of fuets and 100% of chorizos. S. epidermidis was detected in only 11.8% of fuets, and S. carnosus was detected in only 5.9% of chorizos. Lactococcus lactis, Staphylococcus warneri, and Staphylococcus simulans were not detected in any sausage type. From a microbiological point of view, 70.6% of the samples could be considered of high quality, as they had low counts of Enterobacteriaceae and did not contain any of the food-borne pathogens assayed. PMID:12902246

  9. Immunobiotic lactic acid bacteria beneficially regulate immune response triggered by poly(I:C) in porcine intestinal epithelial cells.

    PubMed

    Hosoya, Shoichi; Villena, Julio; Shimazu, Tomoyuki; Tohno, Masanori; Fujie, Hitomi; Chiba, Eriko; Shimosato, Takeshi; Aso, Hisashi; Suda, Yoshihito; Kawai, Yasushi; Saito, Tadao; Alvarez, Susana; Ikegami, Shuji; Itoh, Hiroyuki; Kitazawa, Haruki

    2011-01-01

    This study analyzed the functional expression of TLR3 in various gastrointestinal tissues from adult swine and shows that TLR3 is expressed preferentially in intestinal epithelial cells (IEC), CD172a(+)CD11R1(high) and CD4(+) cells from ileal Peyer's patches. We characterized the inflammatory immune response triggered by TLR3 activation in a clonal porcine intestinal epitheliocyte cell line (PIE cells) and in PIE-immune cell co-cultures, and demonstrated that these systems are valuable tools to study in vitro the immune response triggered by TLR3 on IEC and the interaction between IEC and immune cells. In addition, we selected an immunobiotic lactic acid bacteria strain, Lactobacillus casei MEP221106, able to beneficially regulate the anti-viral immune response triggered by poly(I:C) stimulation in PIE cells. Moreover, we deepened our understanding of the possible mechanisms of immunobiotic action by demonstrating that L. casei MEP221106 modulates the interaction between IEC and immune cells during the generation of a TLR3-mediated immune response. PMID:22046952

  10. Prevalence and impact of single-strain starter cultures of lactic acid bacteria on metabolite formation in sourdough.

    PubMed

    Ravyts, Frédéric; De Vuyst, Luc

    2011-09-01

    Flavour of type II sourdoughs is influenced by the ingredients, processing conditions, and starter culture composition. It is, however, not fully clear to what extent different sourdough lactic acid bacteria (LAB) contribute to flavour. Therefore, two types of flour (rye and wheat) and different LAB starter culture strains were used to prepare sourdoughs, thereby leaving the yeast microbiota uncontrolled. All LAB starter culture strains tested were shown to be prevalent and to acidify the flour/water mixture to pH values between 3.1 and 3.9 after 24h of fermentation. Multiple aldehydes, alcohols, ketones, and carboxylic acids were produced by the sourdough-associated microbiota throughout the fermentation period. Based on the organoleptic evaluation of breads produced with these sourdoughs, five LAB strains were selected to perform prolonged wheat and rye fermentations as to their capacity to result in an acidic (Lactobacillus fermentum IMDO 130101, Lactobacillus plantarum IMDO 130201, and Lactobacillus crustorum LMG 23699), buttermilk-like (Lactobacillus amylovorus DCE 471), or fruity flavour (Lactobacillus sakei CG1). Upon prolonged fermentation, higher metabolite concentrations were produced. For instance, L. sakei CG1 produced the highest amounts of 3-methyl-1-butanol, which was further converted into 3-methylbutyl acetate. The latter compound resulted in a fruity banana flavour after 48h of fermentation, probably due to yeast interference. Rye fermentations resulted in sourdoughs richer in volatiles than wheat, including 3-methyl-1-butanol, 2-phenylethanol, and ethyl acetate. PMID:21645811

  11. The art of strain improvement of industrial lactic acid bacteria without the use of recombinant DNA technology

    PubMed Central

    2014-01-01

    The food industry is constantly striving to develop new products to fulfil the ever changing demands of consumers and the strict requirements of regulatory agencies. For foods based on microbial fermentation, this pushes the boundaries of microbial performance and requires the constant development of new starter cultures with novel properties. Since the use of ingredients in the food industry is tightly regulated and under close scrutiny by consumers, the use of recombinant DNA technology to improve microbial performance is currently not an option. As a result, the focus for improving strains for microbial fermentation is on classical strain improvement methods. Here we review the use of these techniques to improve the functionality of lactic acid bacteria starter cultures for application in industrial-scale food production. Methods will be described for improving the bacteriophage resistance of specific strains, improving their texture forming ability, increasing their tolerance to stress and modulating both the amount and identity of acids produced during fermentation. In addition, approaches to eliminating undesirable properties will be described. Techniques include random mutagenesis, directed evolution and dominant selection schemes. PMID:25186244

  12. Identification and characterization of lactic acid bacteria isolated from mixed pasture of timothy and orchardgrass, and its badly preserved silage.

    PubMed

    Tohno, Masanori; Kobayashi, Hisami; Nomura, Masaru; Uegaki, Ryuichi; Cai, Yimin

    2012-04-01

    In order to understand the relationship between lactic acid bacteria (LAB) species and silage fermentation, a total of 65 LAB strains isolated from mixed pasture of timothy (Phleum pratense L.) and orchardgrass (Dactylis glomerata L.), and its badly preserved silages were subjected to phenotypic and genetic analysis. According to these analyses, the isolates were divided into 13 groups, including Enterococcus gallinarum, Lactobacillus acidipiscis, L. coryniformis subsp. coryniformis, L. coryniformis subsp. torquens, L. curvatus, L. paraplantarum, L. plantarum subsp. argentoratensis, L. plantarum subsp. plantarum, L. sakei subsp. carnosus, Lactococcus garvieae, Lactococcus lactis subsp. cremoris, Leuconostoc pseudomesenteroides, Pediococcus acidilactici, Pediococcus pentosaceus, Weissella hellenica, Weissella paramesenteroides and Carnobacterium divergens. This is the first report to document that C. divergens, L. acidipiscis, L. sakei subsp. carnosus, L. garvieae, phenotypically novel L. lactis subsp. cremoris, E. gallinarum and W. hellenica are present in vegetative forage crops. L. plantarum group strains were most frequently isolated from the badly preserved silages. Some isolates showed a wide range of growth preferences for carbohydrate utilization, optimal growth pH and temperature in vitro, indicating that they have a high growth potential. These results are useful in understanding the diversity of LAB associated with decayed silage of timothy and orchardgrass. PMID:22515692

  13. Molecular and technological characterization of lactic acid bacteria from traditional fermented sausages of Basilicata region (Southern Italy).

    PubMed

    Bonomo, M G; Ricciardi, A; Zotta, T; Parente, E; Salzano, G

    2008-12-01

    Lactic acid bacteria (LAB) from traditional fermented sausages of the Basilicata region were investigated by ARDRA-PCR and RAPD-PCR for taxonomic identification at species and strain level and characterized on the basis of the growth and acidification at different temperatures, incubation times, levels of NaCl and KNO(2), hydrolysis of sarcoplasmatic and myofibrillar proteins and antimicrobial, peptide/amino acid release and nitrate reductase activities. Lactobacillus sakei was the predominant species (67%) followed by Pediococcus pentosaceus (16%), Leuconostoc carnosum (8%), Lactobacillus plantarum (4%), Lactobacillus brevis (2%) and Leuconostoc pseudomesenteroides (2%). The technological characterization revealed that most of the isolates had good acidifying and proteolytic properties. Moreover, Lb. sakei strains showed antimicrobial ability, while Leuconostoc strains the highest reduction of nitrates. This work was a preliminary study in the formulation of autochthonous starter cultures in order to standardize the production process of sausages, to preserve their typical organoleptic and sensory characteristics and to improve the quality of final product. PMID:22063864

  14. Flow cytometric viability assessment of lactic acid bacteria starter cultures produced by fluidized bed drying.

    PubMed

    Bensch, Gerald; Rüger, Marc; Wassermann, Magdalena; Weinholz, Susann; Reichl, Udo; Cordes, Christiana

    2014-06-01

    For starter culture production, fluidized bed drying is an efficient and cost-effective alternative to the most frequently used freeze drying method. However, fluidized bed drying also poses damaging or lethal stress to bacteria. Therefore, investigation of impact of process variables and conditions on viability of starter cultures produced by fluidized bed drying is of major interest. Viability of bacteria is most frequently assessed by plate counting. While reproductive growth of cells can be characterized by the number of colony-forming units, it cannot provide the number of viable-but-nonculturable cells. However, in starter cultures, these cells still contribute to the fermentation during food production. In this study, flow cytometry was applied to assess viability of Lactobacillus plantarum starter cultures by membrane integrity analysis using SYBR®Green I and propidium iodide staining. The enumeration method established allowed for rapid, precise and sensitive determination of viable cell concentration, and was used to investigate effects of fluidized bed drying and storage on viability of L. plantarum. Drying caused substantial membrane damage on cells, most likely due to dehydration and oxidative stress. Nevertheless, high bacterial survival rates were obtained, and granulates contained in the average 2.7?×?10(9) viable cells/g. Furthermore, increased temperatures reduced viability of bacteria during storage. Differences in results of flow cytometry and plate counting suggested an occurrence of viable-but-nonculturable cells during storage. Overall, flow cytometric viability assessment is highly feasible for rapid routine in-process control in production of L. plantarum starter cultures, produced by fluidized bed drying. PMID:24584512

  15. Remediation of polychlorinated biphenyl impacted sediment by concurrent bioaugmentation with anaerobic halorespiring and aerobic degrading bacteria

    PubMed Central

    Payne, Rayford B.; Fagervold, Sonja K.; May, Harold D.; Sowers, Kevin R.

    2013-01-01

    Bioremediation of sediments contaminated with commercial PCBs is potentially achievable by the sequential activity of anaerobic halorespiration to convert higher chlorinated congeners to less chlorinated congeners that are susceptible to aerobic respiratory degradation. The efficacy of bioaugmentation with anaerobic halorespiring “Dehalobium chlorocoercia” DF1 and aerobic Burkholderia xenovorans LB400 added concurrently with GAC as a delivery system was determined in 2-liter laboratory mesocosms containing weathered Aroclor-contaminated sediment from Baltimore Harbor, MD. The greatest effect was seen in the mesocosm bioaugmented with both DF1 and LB400 together, which resulted in an 80% decrease by mass of PCBs, from 8 mg/kg to less than 2 mg/kg after 120 days. There was no significant increase in lesser-chlorinated congeners, indicating that both anaerobic dechlorination by DF1 and aerobic degradation by LB400 occurred. In contrast, non-bioaugmented controls containing filtered culture supernatant showed only 25% decrease in total levels of PCBs after 365 days, which was likely due to biostimulation of the indigenous population by the medium. Direct colony counts and molecular analysis targeting a putative reductive dehalogenase gene of D. chlorocoercia, or the bphA gene of LB400 showed the presence of viable DF1 and LB400 in bioaugmented mesocosms after 365 days, indicating that both non-indigenous strains were sustainable within the indigenous microbial community. These results suggest that an in situ treatment employing the simultaneous application of anaerobic and aerobic microorganisms could be an effective, environmentally sustainable strategy to reduce PCBs levels in contaminated sediment. PMID:23463900

  16. A new environment for aerobic anoxygenic phototrophic bacteria: biological soil crusts.

    PubMed

    Csotonyi, Julius T; Swiderski, Jolantha; Stackebrandt, Erko; Yurkov, Vladimir

    2010-10-01

    Phototrophic microorganisms are critical to the carbon cycling and productivity of biological soil crusts, which enhance water content, nutrient relations and mechanical stability of arid soils. Only oxygen-producing phototrophs, including cyanobacteria and algae, are known from soil crusts, but Earth's second major branch of photosynthetic organisms, the evolutionarily earlier anoxygenic phototrophs, is unreported. We announce the discovery of aerobic anoxygenic phototrophs in three Canadian soil crust communities. We found in a culture-based study that they comprised 0.1-5.9% of the cultivable bacterial community in moss-, lichen- and cyanobacteria-dominated crust from sand dunes and sandy soils. Comparable in density to aerobic phototrophs in other habitats, the bacteriochlorophyll a-possessing pink and orange isolates were related to species of Methylobacterium (99.0-99.5%), Belnapia (97.4-98.8%), Muricoccus (94.4%) and Sphingomonas (96.6-98.5%), based on 16S rRNA gene sequences. Our results demonstrate that proteobacterial anoxygenic phototrophs may be found in dry soil environments, implying desiccation resistance as yet unreported for this group. By utilizing sunlight for part of their energy needs, aerobic phototrophs can accelerate organic carbon cycling in nutrient-poor arid soils. Their effects will be especially important as global climate change enhances soil erosion and consequent nutrient loss. PMID:23766251

  17. Aerobic andFacultatively Anaerobic Bacteria Associated with theGutofCanadaGeese(Branta canadensis) andWhistling Swans(Cygnus columbianus columbianus)

    Microsoft Academic Search

    J. M. DAMARE; R. M. WEINER; R. R. COLWELL

    1979-01-01

    Aerobic andfacultatively anaerobic bacteria fromtheintestinal tracts ofswans andgeesewereisolated andcharacterized aspartofa larger studyofthe microbiological effects ofmigratory waterfowl onwaterquality. A total of356 isolates wereidentified byusing rapididentification methodsandclassified by using numerical taxonomy. A diverse population ofbacteria wasrecovered from thewaterfowl, andrepresentative strains couldbeclassified into21phena. The majority oftheaerobic, heterotrophic bacteria foundinthegutofthewaterfowl werespecies ofEnterobacteriaceae, Streptococcus, Lactobacillus, andBacillus. Unfortunately, thebirds thatwereexamined didnotharborsignificant numbers ofanywaterfowl-specific bacterial species. Thus,itmaynotbepossible

  18. Behaviour of lactic acid bacteria populations in Pecorino di Carmasciano cheese samples submitted to environmental conditions prevailing in the gastrointestinal tract: evaluation by means of a polyphasic approach.

    PubMed

    Ricciardi, Annamaria; Blaiotta, Giuseppe; Di Cerbo, Alessandro; Succi, Mariantonietta; Aponte, Maria

    2014-06-01

    The survival of the autochthonous microflora, of samples collected during Pecorino di Carmasciano cheese manufacturing, was evaluated along the passage through a model mimicking the gastro-intestinal tract. The aim was the selection of lactic acid bacteria potentially able to arrive alive and metabolically active to the colon. The dynamics of lactic microbiota, throughout simulated digestion of cheese samples, were evaluated by means of an approach PCR-DGGE-based. Dominant species after cheese digestion could be related to the Lactobacillus plantarum and Lactobacillus casei groups. Sixty-three strains, which survived to simulated gastro-intestinal transit, were further evaluated for technological features and tolerance to human digestion in several experimental conditions, according to routinely used protocols. Bacterial survival appeared to be, more than strain-specific, strongly affected by experimental conditions, i.e. some strains showed an acceptable survival when resuspended in skim milk but not in ewe milk and vice versa. Nevertheless according to data, one gram of fresh Pecorino di Carmasciano cheese may convey to human colon about the same amount of viable LAB of a probiotic drink. Although it cannot be assumed that lactobacilli introduced with Pecorino have beneficial effects on the host, the healthy impact of autochthonous lactic acid bacteria of naturally fermented food has a broad consensus in the current literature. PMID:24742995

  19. Potential preventive role of lactic acid bacteria against aflatoxin M? immunotoxicity and genotoxicity in mice.

    PubMed

    Ben Salah-Abbès, Jalila; Abbès, Samir; Jebali, Rania; Haous, Zohra; Oueslati, Ridha

    2015-01-01

    Aflatoxin M1 (AFM1) is a mycotoxin produced by numerous Aspergillus species in pre- or post-harvest cereals and milk. Exposure to AFM1 imparts potent economic losses in the livestock industry. Toxicologically, it also causes severe immune system problems. The aims of this study were to evaluate a new AFM1-binding/degrading microorganism for biologic detoxification, to examine its ability to degrade AFM1 in liquid medium, and to evaluate its potential for in vivo preventative effects against AFM1-induced immunotoxicity and genotoxicity in mice. Lactobacillus plantarum MON03 (LP) isolated from Tunisian artisanal butter was found to display significant binding ability to AFM1 in PBS (93%) within 24?h of incubation. Further, the LP was able to tolerate gastric acidity, bile salts, and adhere efficiently to Caco-3 cells in vitro. The in vivo study used Balb/c mice that received either vehicle (control), LP only (at 1?×?10(9)CFU/L, ?1?mg/kg bw), AFM1 (100?mg/kg bw), or AFM1?+?LP daily for 15 days (by gavage); two other groups received a single dose of colchicine (4?mg/kg) or mitomycin C (1?mg/kg) as positive controls for induction of micronuclei and chromosomal aberrations, respectively. The results showed that, compared to in control mice, AFM1 treatment led to significantly decreased body weight gains, and caused cytotoxic/genotoxic effects as indicated by increases in frequencies of polychromatic erythrocytes, as well as those with micronucleation (PCEMN) and chromosomal aberrations, among bone marrow cells. The concurrent administration of LP with AFM1 strongly reduced the adverse effects of AFM1 on each parameter. Mice receiving AFM1?+?LP co-treatment displayed no significant differences in the assayed parameters as compared to the control mice. By itself, the bacteria caused no adverse effects. Based on the data, it is concluded that the test bacteria could potentially be beneficial in the detoxification of AFM1-contaminated foods and feeds for humans and animals. PMID:24738739

  20. Strain-level characterization of nonstarter lactic acid bacteria in Norvegia cheese by high-resolution melt analysis.

    PubMed

    Porcellato, D; Østlie, H M; Liland, K H; Rudi, K; Isaksson, T; Skeie, S B

    2012-09-01

    The nonstarter lactic acid bacteria (NSLAB) constitute an important microbial group found during cheese ripening and they are thought to be fundamental to the quality of cheese. Rapid and accurate diagnostic tests for NSLAB are important for cheese quality control and in understanding the cheese ripening process. Here, we present a novel rapid approach for strain-level characterization through combined 16S rRNA gene and repetitive sequence-based high-resolution melt analysis (HRM). The approach was demonstrated through the characterization of 94 isolates from Norvegia, a Gouda-type cheese. The HRM profiles of the V1 and V3 variable regions of the 16S rRNA gene of the isolates were compared with the HRM profiles of 13 reference strains. The HRM profile comparison of the V1 and V3 regions of the 16S rRNA gene allowed discrimination of isolates and reference strains. Among the cheese isolates, Lactobacillus casei/paracasei (62 isolates) and Lactobacillus plantarum/Lactobacillus pentosus (27 isolates) were the dominant species, whereas Lactobacillus curvatus/Lactobacillus sakei were found occasionally (5 isolates). The HRM profiling of repetitive sequence-based PCR using the (GTG)(5) primer was developed for strain-level characterization. The clustering analysis of the HRM profiles showed high discriminatory power, similar to that of cluster analysis based on the gel method. In conclusion, the HRM approach in this study may be applied as a fast, accurate, and reproducible method for characterization of the NSLAB microflora in cheese and may be applicable to other microbial environments following selective plate culturing. PMID:22916884

  1. Screening of lactic acid bacteria for their potential as microbial cell factories for bioconversion of lignocellulosic feedstocks

    PubMed Central

    2014-01-01

    Background The use of fossil carbon sources for fuels and petrochemicals has serious impacts on our environment and is unable to meet the demand in the future. A promising and sustainable alternative is to substitute fossil carbon sources with microbial cell factories converting lignocellulosic biomass into desirable value added products. However, such bioprocesses require availability of suitable and efficient microbial biocatalysts, capable of utilizing C5 sugars and tolerant to inhibitory compounds generated during pretreatment of biomass. In this study, the performance of a collection of lactic acid bacteria was evaluated regarding their properties with respect to the conversion of lignocellulosic feedstocks. The strains were examined for their ability to utilize xylose and arabinose as well as their resistance towards common inhibitors from pretreated lignocellulosic biomass (furan derivatives, phenolic compounds, weak acids). Results Among 296 tested Lactobacillus and Pediococcus strains, 3?L. pentosus, 1 P. acidilactici and 1 P. pentosaceus isolates were found to be both capable of utilizing xylose and arabinose and highly resistant to the key inhibitors from chemically pretreated lignocellulosic biomass. When tested in broth with commonly found combinations of inhibitors, the selected strains showed merely 4%, 1% and 37% drop in growth rates for sugarcane bagasse, wheat straw and soft wood representatives, respectively, as compared to Escherichia coli MG1655 showing decreased growth rates by 36%, 21% and 90%, respectively, under the same conditions. Conclusion The study showed that some strains of Lactobacilli and Pediococci have the potential to be used as production platforms for value-added products from pretreated lignocellulosic biomass. Selected Lactobacilli and Pediococci strains were able to tolerate the key inhibitors in higher concentrations compared to E.coli; in addition, as these isolates were also capable of fermenting xylose and arabinose, they constitute good candidates for efficient lignocellulosic feedstock bioconversions. PMID:24997803

  2. Rope-producing strains of Bacillus spp. from wheat bread and strategy for their control by lactic acid bacteria.

    PubMed

    Pepe, Olimpia; Blaiotta, Giuseppe; Moschetti, Giancarlo; Greco, Teresa; Villani, Francesco

    2003-04-01

    Two types of white wheat bread (high- and low-type loaves) were investigated for rope spoilage. Thirty of the 56 breads tested developed rope spoilage within 5 days; the high-type loaves were affected by rope spoilage more than the low-type loaves. Sixty-one Bacillus strains were isolated from ropy breads and were characterized on the basis of their phenotypic and genotypic traits. All of the isolates were identified as Bacillus subtilis by biochemical tests, but molecular assays (randomly amplified polymorphic DNA PCR assay, denaturing gradient gel electrophoresis analysis, and sequencing of the V3 region of 16S ribosomal DNA) revealed greater Bacillus species variety in ropy breads. In fact, besides strains of B. subtilis, Bacillus licheniformis, Bacillus cereus, and isolates of Bacillus clausii and Bacillus firmus were also identified. All of the ropy Bacillus isolates exhibited amylase activity, whereas only 32.4% of these isolates were able to produce ropiness in bread slices after treatment at 96 degrees C for 10 min. Strains of lactic acid bacteria previously isolated from sourdough were first selected for antirope activity on bread slices and then used as starters for bread-making experiments. Prevention of growth of approximately 10(4) rope-producing B. subtilis G1 spores per cm(2) on bread slices for more than 15 days was observed when heat-treated cultures of Lactobacillus plantarum E5 and Leuconostoc mesenteroides A27 were added. Growth of B. subtilis G1 occurred after 7 days in breads started with Saccharomyces cerevisiae T22, L. plantarum E5, and L. mesenteroides A27. PMID:12676716

  3. [Expression of human insulin in lactic acid bacteria and its oral administration in non-obese diabetic mice].

    PubMed

    Chen, Si-Wei; Zhong, Jin; Huan, Lian-Dong

    2007-12-01

    Type 1 diabetes mellitus (T1DM) is an auto-immune disease while oral administrating its autoantigens could be a treatment of T1DM. To express human insulin gene (ins) in lactic acid bacteria (LAB) for oral vaccine, ins gene was replaced by LAB bias codon and an 8-amino-acid-residue linker peptide forming a beta-turn was designed to link insulin chain A and B. After synthesized by primer annealing method, the whole ins gene was fused with signal peptide sequence SP(Usp45), subcloned into a LAB secretory expressive vector pSW501 and then introduced to Lactococcus lactis (L. lactis) MG1363 and Lactobacillus casei (Lb. casei ) ATCC27092 respectively. Western blot showed that the expression product (SP(Usp45)-INS protein) targeted mainly at the cell wall while little was found in cytoplasm or supernatant. The highest expression level emerged in exponential phase when the optical density at 600nm of the culture was 0.4. The culture of the recombinant strain Lb. casei/pSW501 was administered to non-obese diabetic (NOD) mice orally. ELISA and Western blot results showed that the recombinant strain could induce SP(Usp45)-INS-specific antibodies and raise IL-4 level (38.583 +/- 2.083 pg/mL, P < 0.05) in the mice' s sera. Expression of insulin in the food-grade vehicle LAB could induce oral immune tolerance in NOD mice and protect it from pancreas injury, suggesting it might be a new way to the treatment of T1DM. PMID:18271251

  4. Taxonomic and molecular characterization of lactic acid bacteria and yeasts in nunu, a Ghanaian fermented milk product.

    PubMed

    Akabanda, Fortune; Owusu-Kwarteng, James; Tano-Debrah, Kwaku; Glover, Richard L K; Nielsen, Dennis S; Jespersen, Lene

    2013-06-01

    Produced from raw unpasteurized milk, nunu is a spontaneously fermented yoghurt-like product made in Ghana and other parts of West Africa. Despite the importance of nunu in the diet of many Africans, there is currently only limited information available on the microorganisms associated with nunu processing. With the aim of obtaining a deeper understanding of the process and as a first step towards developing starter cultures with desired technological properties for nunu production, a microbiological characterization of nunu processing in three different towns in the Upper East region of Ghana, namely Bolgatanga, Paga and Navrongo, was carried out. Lactic acid bacteria (LAB) and yeasts associated with nunu processing were isolated and identified using a combination of pheno- and genotypic methods including morphological and carbohydrate fermentation tests, (GTG)5-based rep-PCR, multiplex PCR, and 16S and 26S rRNA gene sequencing. The LAB counts during nunu processing increased from 4.5 ± 0.4 log cfu/ml at 0 h to 8.7 ± 1.8 log cfu/ml at 24 h of fermentation while yeasts counts increased from 2.8 ± 1.2 log cfu/ml at 0 h to 5.8 ± 0.5 log cfu/ml by the end of fermentation. Lactobacillus fermentum was the dominant LAB throughout the fermentations with Lactobacillus plantarum and Leuconostoc mesenteroides playing prominent roles during the first 6-8 h of fermentation as well. Less frequently isolated LAB included Lactobacillus helveticus, Enterococcus faecium, Enterococcus italicus, Weissella confusa and a putatively novel Lactococcus spp. The yeasts involved were identified as Candida parapsilosis, Candida rugosa, Candida tropicalis, Galactomyces geotrichum, Pichia kudriavzevii and Saccharomyces cerevisiae with P. kudriavzevii and S. cerevisiae being the dominant yeast species. PMID:23541194

  5. Selection of functional lactic acid bacteria as starter cultures for the fermentation of Korean leek (Allium tuberosum Rottler ex Sprengel.).

    PubMed

    Yang, Jaesik; Ji, Yosep; Park, Hyunjoon; Lee, Jieun; Park, Soyoung; Yeo, Soyoung; Shin, Hyunkil; Holzapfel, Wilhelm H

    2014-11-17

    The purpose of this research was to find safe and suitable starter cultures for the fermentation of Korean leek (Allium tuberosum Rottler), also known as garlic chives or Oriental garlic. This traditional herb has several functional properties and a strong flavour; its leaves are used as food material. Eighteen strains of lactic acid bacteria (LAB) were isolated from well-fermented leek kimchi. Controlled fermentation of the leek leaves was conducted with 2 strains (Weissella confusa LK4 and Lactobacillus plantarum LK8), selected as potential starter cultures on the basis of their safety properties, and on the pH, total titratable acidity (TTA), and viable cell numbers [colony forming units (CFUml(-1))] achieved during the fermentation. Microbial dynamics was also followed during fermentation by using PCR-DGGE (Denaturing Gradient Gel Electrophoresis) on DNA level. To analyse bioactive compounds such as thiols and allicin (diallyl thiosulfinates), the total flavonoid and polyphenolic contents were determined by colorimetric methods. Functional properties were assessed on the basis of anti-oxidative capacities by determining the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging effect, and ferric reducing antioxidant power (FRAP). W. confusa LK4 rapidly increased during the first stage of leek fermentation, and was mainly responsible for accelerated fermentation during the early period in contrast to L. plantarum LK8, a stronger acid producer during the later stages of fermentation. After 48 h fermentation, leeks fermented with W. confusa LK4 showed the highest radical scavenging effects and reducing ability. The detectable amount of allicin of fermented leeks decreased relative to the change in pH, whereas the concentration of thiols significantly increased. Total flavonoid and poly-phenolic contents changed during fermentation and showed correlation with anti-oxidant effects. We therefore suggest the suitability of W. confusa LK4 as a potential starter culture for fermentation of leeks. PMID:25279760

  6. Occurrence and activity of sulphate reducing bacteria in aerobic activated sludge systems.

    PubMed

    van den Brand, T P H; Roest, K; Chen, G H; Brdjanovic, D; van Loosdrecht, M C M

    2015-03-01

    In the sewage or wastewater treatment plant, biological sulphate reduction can occur spontaneously or be applied beneficially for its treatment. The results of this study can be applied to control SRB in the sewage and WWTP. Therefore, population diversity analyses of SRB for nine activated sludge wastewater treatment plants (WWTP) in the Netherlands and the effect of long-term (months) oxygen exposures on the SRB activity were carried out. T-RFLP and clone sequencing analyses of winter and summer samples revealed that (1) all WWTP have a similar SRB population, (2) there is no seasonal impact (10-20 °C) on the SRB population present in the WWTP and (3) Desulfobacter postgatei, Desulfovibrio desulfuricans and Desulfovibrio intestinalis were the most common and dominant SRB species observed in these samples, and origin from the sewage. Short term activity tests demonstrated that SRB were not active in the aerobic WWTP, but while flushed with N2-gas SRB became slightly active after 3 h. In a laboratory reactor at a dissolved oxygen concentration of <2 %, sulphate reduction occurred and 89 % COD removal was achieved. SRB grew in granules, in order to protect themselves for oxygen exposures. SRB are naturally present in aerobic WWTP, which is due to the formation of granules. PMID:25649202

  7. Colonization by aerobic bacteria in karst: Laboratory and in situ experiments

    USGS Publications Warehouse

    Personne, J.-C.; Poty, F.; Mahler, B.J.; Drogue, C.

    2004-01-01

    Experiments were carried out to investigate the potential for bacterial colonization of different substrates in karst aquifers and the nature of the colonizing bacteria. Laboratory batch experiments were performed using limestone and PVC as substrates, a natural bacterial isolate and a known laboratory strain (Escherichia coli [E. coli]) as inocula, and karst ground water and a synthetic formula as growth media. In parallel, fragments of limestone and granite were submerged in boreholes penetrating two karst aquifers for more than one year; the boreholes are periodically contaminated by enteric bacteria from waste water. Once a month, rock samples were removed and the colonizing bacteria quantified and identified. The batch experiments demonstrated that the natural isolate and E. coli both readily colonized limestone surfaces using karst ground water as the growth medium. In contrast, bacterial colonization of both the limestone and granite substrates, when submerged in the karst, was less intense. More than 300 bacterial strains were isolated over the period sampled, but no temporal pattern in colonization was seen as far as strain, and colonization by E. coli was notably absent, although strains of Salmonella and Citrobacter were each observed once. Samples suspended in boreholes penetrating highly fractured zones were less densely colonized than those in the borehole penetrating a less fractured zone. The results suggest that contamination of karst aquifers by enteric bacteria is unlikely to be persistent. We hypothesize that this may be a result of the high flow velocities found in karst conduits, and of predation of colonizing bacteria by autochthonous zooplankton.

  8. Contribution of Aerobic Photoheterotrophic Bacteria to the Carbon Cycle in the Ocean

    Microsoft Academic Search

    Zbigniew S. Kolber; F. Gerald Plumley; Andrew S. Lang; J. Thomas Beatty; Robert E. Blankenship; Cindy L. VanDover; Costantino Vetriani; Michal Koblizek; Christopher Rathgeber; Paul G. Falkowski

    2001-01-01

    The vertical distribution of bacteriochlorophyll a, the numbers of infrared fluorescent cells, and the variable fluorescence signal at 880 nanometers wave- length, all indicate that photosynthetically competent anoxygenic phototrophic bacteria are abundant in the upper open ocean and comprise at least 11% of the total microbial community. These organisms are facultative photohetero- trophs, metabolizing organic carbon when available, but are

  9. Distribution of aerobic bacteria, protozoa, algae, and fungi in deep subsurface sediments

    Microsoft Academic Search

    J. L. Sinclair; W. C. Ghiorse

    1989-01-01

    The distribution of microorganisms in deep subsurface profiles was determined at three sites at the Savannah River Plant, Aiken, South Carolina. Acridine orange direct counts (AODC) of bacteria were highest in surface soil samples and declined to the 10 to 10 per gram range in the subsurface, but then did not decline further with depth. In the subsurface, AODC values

  10. Diversity and activity of cultivable aerobic planktonic bacteria of a saline Lake located in Sovata, Romania.

    PubMed

    Borsodi, A K; Kiss, R I; Cech, G; Vajna, B; Tóth, E M; Márialigeti, K

    2010-09-01

    Aerobic bacterial strains from the salt water of Lake Red (Sovata, Romania) were cultivated. More than half of the 80 strains were G(-) and formed motile straight rods. Only a few strains produced acid from D-glucose and reduced nitrate to nitrite. Optimum NaCl concentration for growth varied between 5 and 15 % in the majority of the strains, so the isolates were regarded moderately halophilic. On the basis of the 16S rRNA gene sequence similarity almost half of the strains were identified as members of genus Halomonas. Other strains belonged to genera Marinobacter, Psychrobacter, Serratia, Morganella (?-Proteobacteria), Bacillus, Exiguobacterium, Planococcus (Firmicutes), and Arthrobacter, Micrococcus, Microbacterium, and Nesterenkonia (Actinobacteria). PMID:20941581

  11. Inhibitory potential of tea polyphenolics and influence of extraction time against Helicobacter pylori and lack of inhibition of beneficial lactic acid bacteria.

    PubMed

    Ankolekar, Chandrakant; Johnson, David; Pinto, Marcia da Silva; Johnson, Kevin; Labbe, Ronald; Shetty, Kalidas

    2011-11-01

    Tea polyphenolics such as catechins are known to have the potential to inhibit many bacterial pathogens. Helicobacter pylori has been identified as an etiologic agent in the development of gastric ulcer, peptic ulcer, gastritis, and many other stomach-related diseases. In this study, we investigated the effect of 9 tea extracts--3 different brands representing 4 different processed types (white, green, oolong, and black)--on the inhibition of H. pylori. Extraction times of 2 and 5 minutes were compared. Most 5-minute extracts showed H. pylori inhibition, whereas 2-minute extracts only of Choice darjeeling black and Tazo white showed inhibition. No recovery was observed after the addition of 0.5 and 5 mM proline, indicating that tea polyphenols do not inhibit H. pylori by inhibition of proline oxidation via proline dehydrogenase. Extracts that showed inhibition were further evaluated for their effect on beneficial lactic acid bacteria. None of the samples showed inhibition, suggesting that tea might be able to inhibit H. pylori without affecting the beneficial lactic acid bacteria. High-performance liquid chromatography indicated the presence of gallic acid, quercetin, caffeine, and tea catechins (including catechin, epicatechin, and epigallocatechin) in all the tea samples. Our study indicates that tea can be potentially used as a low-cost dietary support to combat H. pylori-linked gastric diseases without affecting the beneficial intestinal bacteria. PMID:21663484

  12. Anaerobic and aerobic bacteriology of the saliva and gingiva from 16 captive Komodo dragons (Varanus komodoensis): new implications for the "bacteria as venom" model.

    PubMed

    Goldstein, Ellie J C; Tyrrell, Kerin L; Citron, Diane M; Cox, Cathleen R; Recchio, Ian M; Okimoto, Ben; Bryja, Judith; Fry, Bryan G

    2013-06-01

    It has been speculated that the oral flora of the Komodo dragon (Varanus komodoensis) exerts a lethal effect on its prey; yet, scant information about their specific oral flora bacteriology, especially anaerobes, exists. Consequently, the aerobic and anaerobic oral bacteriology of 16 captive Komodo dragons (10 adults and six neonates), aged 2-17 yr for adults and 7-10 days for neonates, from three U.S. zoos were studied. Saliva and gingival samples were collected by zoo personnel, inoculated into anaerobic transport media, and delivered by courier to a reference laboratory. Samples were cultured for aerobes and anaerobes. Strains were identified by standard methods and 16S rRNA gene sequencing when required. The oral flora consisted of 39 aerobic and 21 anaerobic species, with some variation by zoo. Adult dragons grew 128 isolates, including 37 aerobic gram-negative rods (one to eight per specimen), especially Enterobacteriaceae; 50 aerobic gram-positive bacteria (two to nine per specimen), especially Staphylococcus sciuri and Enterococcusfaecalis, present in eight of 10 and nine of 10 dragons, respectively; and 41 anaerobes (one to six per specimen), especially clostridia. All hatchlings grew aerobes but none grew anaerobes. No virulent species were isolated. As with other carnivores, captive Komodo oral flora is simply reflective of the gut and skin flora of their recent meals and environment and is unlikely to cause rapid fatal infection. PMID:23805543

  13. Importance of unattached bacteria and bacteria attached to sediment in determining potentials for degradation of xenobiotic organic contaminants in an aerobic aquifer.

    PubMed Central

    Holm, P E; Nielsen, P H; Albrechtsen, H J; Christensen, T H

    1992-01-01

    The bacterial abundance, distribution, and degradation potential (in terms of degradation versus lack of degradation) for four xenobiotic compounds in an aerobic aquifer sediment have been examined in laboratory and field experiments. The xenobiotic compounds studied were benzene, toluene, o-xylene, and naphthalene (all at concentrations of approximately 120 micrograms/liter). The aerobic degradation experiments ran for approximately 90 days at 10 degrees C, which corresponded to the groundwater temperature. At the end of the experiment, the major part of the microbial biomass, quantified as acridine orange direct counts, was attached to the groundwater sediment (18 x 10(6) to 25 x 10(6) cells per g [dry weight], and only a minor part was unattached in the groundwater (0.6 x 10(6) to 5.5 x 10(6) cells per ml). Experiments involving aquifer sediment suspensions showed identical degradation potentials in the laboratory and in the field. However, laboratory experiments involving only groundwater (excluding aquifer sediment) showed less degradation potential than in situ experiments involving only groundwater, indicating that the manipulation or approach of the laboratory experiments could affect the determination of the degradation potentials. No differences were observed between the groundwater-only and the sediment compartments in the in situ experiments in the ability to degrade the compounds, but the maximum degradation rates were substantially lower in the groundwater-only compartment. Preparations used in laboratory experiments for studying the degradation potential for xenobiotic organic contaminants should contain sediment to obtain the highest numbers of bacteria as well as the broadest and most stable degradation.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1444415

  14. Cloning and Heterologous Production of Hiracin JM79, a Sec-Dependent Bacteriocin Produced by Enterococcus hirae DCH5, in Lactic Acid Bacteria and Pichia pastoris

    Microsoft Academic Search

    Jorge Sanchez; Juan Borrero; Beatriz Gomez-Sala; Antonio Basanta; Carmen Herranz; Luis M. Cintas; Pablo E. Hernandez

    2008-01-01

    Hiracin JM79 (HirJM79), a Sec-dependent bacteriocin produced by Enterococcus hirae DCH5, was cloned and produced in Lactococcus lactis, Lactobacillus sakei, Enterococcus faecium, Enterococcus faecalis, and Pichia pastoris. For heterologous production of HirJM79 in lactic acid bacteria (LAB), the HirJM79 structural gene (hirJM79), with or without the HirJM79 immunity gene (hiriJM79), was cloned into the plasmid pMG36c under the control of

  15. Development of human lactic acid (LAB) gastrointestinal microbiota in a Greek rural population

    Microsoft Academic Search

    Dimitrios Vassos; Vassiliki Maipa; Chrysa Voidarou; Athanasios Alexopoulos; Eugenia Bezirtzoglou

    2008-01-01

    In order to investigate the Lactic Acid Bacteria (LAB) of the gut, fecal samples were collected and analyzed from 120 healthy\\u000a Greek volunteers ranging from age 1 to age 85, all of whom declared daily consumption of local fermented dairy products. LAB\\u000a strains were isolated using selective media under aerobic or anaerobic conditions. Identification of the isolates was based\\u000a on

  16. Mechanisms regulating the reduction of selenite by aerobic gram (+) and ({minus}) bacteria

    SciTech Connect

    Garbisu, C.; Ishii, Takahisa; Yee, B.C.; Carlson, D.E.; Buchanan, B.B.; Leighton, T. [Univ. of California, Berkeley, CA (United States); Smith, N.R. [California State Univ., Hayward, CA (United States). Dept. of Biological Sciences; Yee, A. [Lawrence Berkeley Lab., CA (United States). Div. of Earth Sciences

    1995-12-31

    Toxic species of selenium are pollutants found in agricultural and oil refinery wastestreams. Selenium contamination is particularly problematic in areas that have seleniferous subsurface geology, such as the central valley of California. The authors are developed a bacterial treatment system to mitigate selenium-contaminated wastestreams using Bacillus subtilis and Pseudomonas fluorescens, respectively, as model gram (+) and ({minus}) soil bacteria. They have found that, during growth, both organisms reduce selenite, a major soluble toxic species, to red elemental selenium--an insoluble product generally regarded as nontoxic. In both cases, reduction depended on growth substrate and was effected by an inducible system that effectively removed selenite at concentrations typical of polluted sites--i.e., 50 to 300 {micro}g/L. The bacteria studied differed in one respect: when grown in medium supplemented with nitrate or sulfate, the ability of P. fluorescens to remediate selenite was enhanced, whereas that of B. subtilis was unchanged. Current efforts are being directed toward understanding the biochemical mechanism(s) of detoxification and determining whether bacteria occurring in polluted environments such as soils and sludge systems are capable of selenite remediation.

  17. Aerobic degradation of a mixture of azo dyes in a packed bed reactor having bacteria-coated laterite pebbles.

    PubMed

    Senan, Resmi C; Shaffiqu, T S; Roy, J Jegan; Abraham, T Emilia

    2003-01-01

    A microbial consortium capable of aerobic degradation of a mixture of azo dyes consisting of two isolated strains (RRL,TVM) and one known strain of Pseudomonas putida (MTCC 1194) was immobilized on laterite stones. The amount of bacterial biomass attached to the laterite stones was 8.64 g per 100 g of the stone on a dry weight basis. The packed bed reactor was filled with these stones and had a total capacity of 850 mL and a void volume of 210 mL. The feed consisted of an equal mixture of seven azo dyes both in water as well as in a simulated textile effluent, at a pH of 9.0 and a salinity of 900 mg/L. The dye concentrations of influent were 25, 50, and 100 microg/mL. The residence time was varied between 0.78 and 6.23 h. It was found that at the lowest residence time 23.55, 45.73, and 79.95 microg of dye was degraded per hour at an initial dye concentration of 25, 50, and 100 microg, respectively. The pH was reduced from 9.0 to 7.0. Simulated textile effluent containing 50 microg/mL dye was degraded by 61.7%. Analysis of degradation products by TLC and HPLC showed that the dye mixture was degraded to nontoxic smaller molecules. The bacteria-coated pebbles were stable, there was no washout even after 2 months, and the reactor was found to be suitable for the aerobic degradation of azo dyes. PMID:12675610

  18. Phenotypic and genotypic identification of lactic acid bacteria isolated from traditional pickles of the Çubuk region in Turkey.

    PubMed

    Ba?der Elmac?, Simel; Tokatl?, Mehmet; Dursun, Derya; Özçelik, Filiz; ?anl?baba, P?nar

    2015-05-01

    A total of 152 lactic acid bacteria (LAB) were isolated from pickles produced in the Ankara-Çubuk region. These isolates were clustered into eight groups on the basis of their phenotypic characteristics including cell morphology, CO2 production from glucose, growth at 10 and 45 °C, growth in 6.5 % NaCl, and growth at pH 9.6. API 50 CH carbohydrate fermentation test, 16S ribosomal RNA (rRNA) sequence analysis, and sodium dodecyl sulfate-acrylamide gel electrophoresis (SDS-PAGE) whole-cell protein profile analysis were also performed for precise identification of the isolates at the species level. Molecular identification revealed that the most prevalent LAB species involved in pickle fermentation were Pediococcus ethanolidurans (46 isolates, 30.3 %), Lactobacillus brevis (37 isolates, 24.3 %), Lactobacillus plantarum (37 isolates, 24.3 %), and Lactobacillus buchneri (15 isolates, 9.9 %). Other LAB were found in minor frequencies such as Pediococcus parvulus (8 isolates, 5.3 %), Lactobacillus namurensis (6 isolates, 3.9 %), Lactobacillus diolivorans (1 isolate, 0.7 %), Lactobacillus parabrevis (1 isolate, 0.7 %), and Enterococcus casseliflavus (1 isolate, 0.7 %). When results of phenotypic and genotypic identification methods were compared, differences in the species distribution of LAB associated with pickles were defined between the API and the 16S rRNA sequencing. The API 50 CHL test coincided with the 16S rRNA results in 71 out of the 152 tested isolates, indicating that API gave unreliable identification results. A clear correlation could not be found between the results of whole-cell SDS profiles and 16S rRNA sequencing. Therefore, molecular characterization by 16S rRNA sequencing was considered to be the most reliable method for identifying isolates. The results presented in this work provide insight in to the LAB population associated with traditional Çubuk pickles and constitute a LAB strain resource for further studies involving the development of starter cultures. PMID:25404550

  19. Influence of lactic acid bacteria on redox status and on proteolytic activity of buckwheat (Fagopyrum esculentum Moench) sourdoughs.

    PubMed

    Capuani, Alessandro; Behr, Jürgen; Vogel, Rudi F

    2013-07-15

    Redox potential and proteolysis determine protein networks in doughs and thus dough rheology as well as the structure of baked goods. Namely, gluten-free bakery products needs structural improvements but little is known about these parameters in gluten free dough systems. In this work the influence of lactic acid bacteria (LAB) on redox status and proteolysis of buckwheat sourdoughs was investigated. An increase of free thiol groups was detected as redox potential was decreasing during fermentation. Thiol content at 8 h was higher in doughs fermented with strains with high reductive activity, such as Weissella (W.) cibaria in comparison to Pediococcus (P.) pentosaceus, which exhibited a lower reducing activity. At 24 h each fermentation showed a similar content of free thiol groups. Endogenous buckwheat proteases were characterized using various protease inhibitors in buckwheat doughs. Until pH3.1 a proteolysis increase was monitored in doughs. Employed LAB didn't show any detectable extracellular proteolytic activity. Flour proteases are thus responsible for protein breakdown, and this was demonstrated comparing free amino nitrogen (FAN) values and protein electrophoretic patterns of sourdough fermentations with chemical acidified (CA) doughs. FAN content at 24 h using P. pentosaceus, proteolytic comparative strain of Enterococcus faecalis, W. cibaria, mixed culture (containing P. pentosaceus and W. cibaria), CA and CA doughs containing glutathione (GSH) reached 45.9±1.3, 42.4±1.3, 40±1, 31±2, 29±2 and 17.8±3.9 mmol kg(-1) flour, respectively. Proteolysis was mainly influenced by pH and incubation time. The addition of GSH showed a decrease of proteolysis and of free amino acids. CA doughs showed a higher total free amino acids content than sourdough fermented with LAB indicating their metabolization. Fermentations with high FAN values exhibited lower band intensity (analyzed under reducing condition) in electrophoretic patterns. These results show that dough proteases are responsible for proteolysis in buckwheat sourdoughs and this activity is influenced from LAB metabolism. Moreover, oxidation-reduction potential (ORP) changes do not show improvements of proteolytic activity in buckwheat sourdoughs. PMID:23728431

  20. Proteolysis by Sourdough Lactic Acid Bacteria: Effects on Wheat Flour Protein Fractions and Gliadin Peptides Involved in Human Cereal Intolerance

    PubMed Central

    Di Cagno, Raffaella; De Angelis, Maria; Lavermicocca, Paola; De Vincenzi, Massimo; Giovannini, Claudio; Faccia, Michele; Gobbetti, Marco

    2002-01-01

    Sourdough lactic acid bacteria were preliminarily screened for proteolytic activity by using a digest of albumin and globulin polypeptides as a substrate. Based on their hydrolysis profile patterns, Lactobacillus alimentarius 15M, Lactobacillus brevis 14G, Lactobacillus sanfranciscensis 7A, and Lactobacillus hilgardii 51B were selected and used in sourdough fermentation. A fractionated method of protein extraction and subsequent two-dimensional electrophoresis were used to estimate proteolysis in sourdoughs. Compared to a chemically acidified (pH 4.4) dough, 37 to 42 polypeptides, distributed over a wide range of pIs and molecular masses, were hydrolyzed by L. alimentarius 15M, L. brevis 14G, and L. sanfranciscensis 7A. Albumin, globulin, and gliadin fractions were hydrolyzed, while glutenins were not degraded. The concentrations of free amino acids, especially proline and glutamic and aspartic acids, also increased in sourdoughs. Compared to the chemically acidified dough, proteolysis by lactobacilli positively influenced the softening of the dough during fermentation, as determined by rheological analyses. Enzyme preparations of the selected lactobacilli which contained proteinase or peptidase enzymes showed hydrolysis of the 31-43 fragment of A-gliadin, a toxic peptide for celiac patients. A toxic peptic-tryptic (PT) digest of gliadins was used for in vitro agglutination tests on K 562 (S) subclone cells of human myelagenous leukemia origin. The lowest concentration of PT digest that agglutinated 100% of the total cells was 0.218 g/liter. Hydrolysis of the PT digest by proteolytic enzymes of L. alimentarius 15M and L. brevis 14G completely prevented agglutination of the K 562 (S) cells by the PT digest at a concentration of 0.875 g/liter. Considerable inhibitory effects by other strains and at higher concentrations of the PT digest were also found. The mixture of peptides produced by enzyme preparations of selected lactobacilli showed a decreased agglutination of K 562 (S) cells with respect to the whole 31-43 fragment of A-gliadin. PMID:11823200

  1. The development of lactic acid bacteria and Lactobacillus buchneri and their effects on the fermentation of alfalfa silage.

    PubMed

    Schmidt, R J; Hu, W; Mills, J A; Kung, L

    2009-10-01

    This study was conducted to document the development of populations of lactic acid bacteria (LAB) and Lactobacillus buchneri in alfalfa silage treated with various inoculants. Wilted and chopped alfalfa (45% dry matter) was treated with 1) distilled water (untreated, U), 2) Lactobacillus buchneri 40788 (4 x 10(5) cfu/g; LB), or 3) L. buchneri 40788 (4 x 10(5) cfu/g) and Pediococcus pentosaceus (1 x 10(5) cfu/g; LBPP). Forages were packed into triplicate vacuum-sealed, nylon-polyethylene bags per treatment, and ensiled for 2, 5, 45, 90, and 180 d. Viable (cfu) LAB in forage and silage were quantified by traditional plating on selective agar, and numbers of L. buchneri (cfu-equivalent, cfu-E) were quantified by real-time quantitative PCR. Fresh, untreated forage had 5.52 log cfu of LAB/g and 3.79 log cfu-E of L. buchneri/g. After 2 d of ensiling, numbers of LAB increased to >8 log cfu/g in all silages. In contrast, numbers of L. buchneri in U remained below 4 log cfu-E/g but reached approximately 7 log cfu-E/g in LB and LBPP. From d 5 onward, numbers of L. buchneri in U remained below 6 log cfu-E/g but approached 9 log cfu-E/g in LB and LBPP. The pH was lower in LBPP compared with U and LB after 2 and 5 d of ensiling, but pH was lower for U compared with LB and LBPP thereafter. Treatments LB and LBPP had more acetic acid than U at 45 d of ensiling, which coincided with detectable amounts of 1,2 propanediol. Inoculation with LBPP resulted in silage with the highest concentration of 1,2 propanediol after 180 d of ensiling. From d 45 onward, LB and LBPP silages had lower concentrations of residual water-soluble carbohydrates but had higher concentrations of ammonia-N than U. In conclusion, epiphytic L. buchneri can be detected in alfalfa but this population is unable to lead the silage fermentation. In contrast, when L. buchneri was added to silage as an inoculant, the numbers of L. buchneri (cfu-E) increased markedly but did not dictate fermentation until 45 d of ensiling. These findings help to explain why the response (in increased acetic acid) from the addition of L. buchneri in silages is not immediate. PMID:19762819

  2. Population Changes in Enteric Bacteria and Other Microorganisms During Aerobic Thermophilic Windrow Composting1

    PubMed Central

    Savage, Jacob; Chase, Theodore; Macmillan, James D.

    1973-01-01

    Composting of wastes from swine feeding operations was studied. The effects of the frequency of turning the wastes and addition of straw to improve the physical structure were studied to determine the most effective technique to rapidly increase the temperature and, consequently, destroy coliforms and Salmonella. Four different treatments were studied; the results showed that, with addition of 5% (wt/wt) straw and mechanical turning of the compost 20 times per week, the temperature reached 60 C within 3 days and enteric bacteria were destroyed within 14 days. Images PMID:4203338

  3. Effect of lactic acid bacteria inoculant and beet pulp addition on fermentation characteristics and in vitro ruminal digestion of vegetable residue silage.

    PubMed

    Cao, Y; Cai, Y; Takahashi, T; Yoshida, N; Tohno, M; Uegaki, R; Nonaka, K; Terada, F

    2011-08-01

    The objective of this study was to determine the effect of beet pulp (BP) and lactic acid bacteria (LAB) on silage fermentation quality and in vitro ruminal dry matter (DM) digestion of vegetable residues, including white cabbage, Chinese cabbage, red cabbage, and lettuce. Silage was prepared using a small-scale fermentation system, and treatments were designed as control silage without additive or with BP (30% fresh matter basis), LAB inoculant Chikuso-1 (Lactobacillus plantarum, 5mg/kg, fresh matter basis), and BP+LAB. In vitro incubation was performed using rumen fluid mixed with McDougall's artificial saliva (at a ratio of 1:4, vol/vol) at 39°C for 6h to determine the ruminal fermentability of the vegetable residue silages. These vegetable residues contained high levels of crude protein (20.6-22.8% of DM) and moderate levels of neutral detergent fiber (22.7-33.6% of DM). In all silages, the pH sharply decreased and lactic acid increased, and the growth of bacilli, coliform bacteria, molds, and yeasts was inhibited by the low pH at the early stage of ensiling. The silage treated with BP or LAB had a lower pH and a higher lactic acid content than the control silage. After 6h of incubation, all silages had relatively high DM digestibility (38.6-44.9%); in particular, the LAB-inoculated silage had the highest DM digestibility and the lowest methane production. The vegetable residues had high nutritional content and high in vitro DM digestibility. Also, both the addition of a LAB inoculant and moisture adjustment with BP improved the fermentation quality of the vegetable residue silages. In addition, LAB increased DM digestibility and decreased ruminal methane production. PMID:21787927

  4. Effects of feeding of two potentially probiotic preparations from lactic acid bacteria on the performance and faecal microflora of broiler chickens.

    PubMed

    Fajardo, Paula; Pastrana, Lorenzo; Méndez, Jesús; Rodríguez, Isabel; Fuciños, Clara; Guerra, Nelson P

    2012-01-01

    The aim of this study was to evaluate the potential of two probiotic preparations, containing live lactic acid bacteria (Lactococcus lactis CECT 539 and Lactobacillus casei CECT 4043) and their products of fermentation (organic acids and bacteriocins), as a replacement for antibiotics in stimulating health and growth of broiler chickens. The effects of the supplementation of both preparations (with proven probiotic effect in weaned piglets) and an antibiotic (avilamycin) on body weight gain (BWG), feed intake (FI), feed consumption efficiency (FCE), relative intestinal weight, and intestinal microbiota counts were studied in 1-day posthatch chickens. The experiments were conducted with medium-growth Sasso X44 chickens housed in cages and with nutritional stressed Ross 308 broiler distributed in pens. Consumption of the different diets did not affect significantly the final coliform counts in Sasso X44 chickens. However, counts of lactic acid bacteria and mesophilic microorganisms were higher in the animals receiving the two probiotic preparations (P < 0.05). In the second experiment, although no differences in BWG were observed between treatments, Ross 308 broilers receiving the probiotic Lactobacillus preparation exhibited the lowest FCE values and were considered the most efficient at converting feed into live weight. PMID:22666137

  5. Sensory evaluation and consumer acceptance of naturally and lactic acid bacteria-fermented pastes of soybeans and soybean–maize blends

    PubMed Central

    Ng'ong'ola-Manani, Tinna A; Mwangwela, Agnes M; Schüller, Reidar B; Østlie, Hilde M; Wicklund, Trude

    2014-01-01

    Fermented pastes of soybeans and soybean–maize blends were evaluated to determine sensory properties driving consumer liking. Pastes composed of 100% soybeans, 90% soybeans and 10% maize, and 75% soybeans and 25% maize were naturally fermented (NFP), and lactic acid bacteria fermented (LFP). Lactic acid bacteria fermentation was achieved through backslopping using a fermented cereal gruel, thobwa. Ten trained panelists evaluated intensities of 34 descriptors, of which 27 were significantly different (P < 0.05). The LFP were strong in brown color, sourness, umami, roasted soybean-and maize-associated aromas, and sogginess while NFP had high intensities of yellow color, pH, raw soybean, and rancid odors, fried egg, and fermented aromas and softness. Although there was consumer (n = 150) heterogeneity in preference, external preference mapping showed that most consumers preferred NFP. Drivers of liking of NFP samples were softness, pH, fermented aroma, sweetness, fried egg aroma, fried egg-like appearance, raw soybean, and rancid odors. Optimization of the desirable properties of the pastes would increase utilization and acceptance of fermented soybeans. PMID:24804070

  6. Sensory evaluation and consumer acceptance of naturally and lactic acid bacteria-fermented pastes of soybeans and soybean-maize blends.

    PubMed

    Ng'ong'ola-Manani, Tinna A; Mwangwela, Agnes M; Schüller, Reidar B; Ostlie, Hilde M; Wicklund, Trude

    2014-03-01

    Fermented pastes of soybeans and soybean-maize blends were evaluated to determine sensory properties driving consumer liking. Pastes composed of 100% soybeans, 90% soybeans and 10% maize, and 75% soybeans and 25% maize were naturally fermented (NFP), and lactic acid bacteria fermented (LFP). Lactic acid bacteria fermentation was achieved through backslopping using a fermented cereal gruel, thobwa. Ten trained panelists evaluated intensities of 34 descriptors, of which 27 were significantly different (P < 0.05). The LFP were strong in brown color, sourness, umami, roasted soybean-and maize-associated aromas, and sogginess while NFP had high intensities of yellow color, pH, raw soybean, and rancid odors, fried egg, and fermented aromas and softness. Although there was consumer (n = 150) heterogeneity in preference, external preference mapping showed that most consumers preferred NFP. Drivers of liking of NFP samples were softness, pH, fermented aroma, sweetness, fried egg aroma, fried egg-like appearance, raw soybean, and rancid odors. Optimization of the desirable properties of the pastes would increase utilization and acceptance of fermented soybeans. PMID:24804070

  7. Exploitation of Albanian wheat cultivars: characterization of the flours and lactic acid bacteria microbiota, and selection of starters for sourdough fermentation.

    PubMed

    Nionelli, Luana; Curri, Nertila; Curiel, José Antonio; Di Cagno, Raffaella; Pontonio, Erica; Cavoski, Ivana; Gobbetti, Marco; Rizzello, Carlo Giuseppe

    2014-12-01

    Six Albanian soft and durum wheat cultivars were characterized based on chemical and technological features, showing different attitudes for bread making. Gliadin and glutenin fractions were selectively extracted from flours, and subjected to two-dimensional electrophoresis. Linja 7 and LVS flours showed the best characteristics, and abundance of high molecular weight (HMW)-glutenins. Type I sourdoughs were prepared through back slopping procedure, and the lactic acid bacteria were typed and identified. Lactobacillus plantarum and Leuconostoc mesenteroides were the predominant species. Thirty-eight representative isolates were singly used for sourdough fermentation of soft and durum wheat Albanian flours and their selection was carried out based on growth and acidification, quotient of fermentation, and proteolytic activity. Two different pools of lactic acid bacteria were designed to ferment soft or durum wheat flours. Sourdough fermentation with mixed and selected starters positively affected the quotient of fermentation, concentration of free amino acids, profile of phenolic acids, and antioxidant and phytase activities. This study provided the basis to exploit the potential of wheat Albanian flours based on an integrated approach, which considered the characterization of the flours and the processing conditions. PMID:25084651

  8. 16S ribosomal DNA analysis and characterization of lactic acid bacteria associated with traditional Tibetan Qula cheese made from yak milk.

    PubMed

    Tan, Zhongfang; Pang, Huili; Duan, Yuheng; Qin, Guangyong; Cai, Yimin

    2010-12-01

    Twenty strains of lactic acid bacteria were isolated from six traditional Tibetan Qula cheese made from yak which were collected from northwest China, including Tibet, Qinghai and Gansu province. These isolates were subjected to phenotypic and genetic analyses. All isolates were Gram-positive and catalase-negative cocci that produced gas from glucose and formed D(-) isomer of lactate. Most isolates were able to grow in de Man, Rogosa and Sharpe (MRS) broth at pH values 3.0-9.0 and in 6.5% NaCl (w/v). According to analytical profile index 50 carbohydrates (API 50 CH) fermentation patterns of amygdalin and arabinose, these isolates were divided into three groups (A to C). On the basis of the phylogenetic trees of 16S ribosomal DNA (rDNA) sequence, the strains in all groups were placed in the cluster making up the genus Leuconostoc, which showed that all strains should belong to Leuconostoc species. Strains in Group A and Group B exhibited similarity of 16S rDNA sequence of over 99% to Leuconostoc mesenteroides, indicating that they each comprised a single species. Strains in group C were assigned to the Leuconostoc pseudomesenteroides and their 16S rDNA sequence showed a similarity of over 99%. This study demonstrated that Leuconostoc was the dominant member among lactic acid bacteria in Qula cheese. PMID:21108692

  9. Effects of Feeding of Two Potentially Probiotic Preparations from Lactic Acid Bacteria on the Performance and Faecal Microflora of Broiler Chickens

    PubMed Central

    Fajardo, Paula; Pastrana, Lorenzo; Méndez, Jesús; Rodríguez, Isabel; Fuciños, Clara; Guerra, Nelson P.

    2012-01-01

    The aim of this study was to evaluate the potential of two probiotic preparations, containing live lactic acid bacteria (Lactococcus lactis CECT 539 and Lactobacillus casei CECT 4043) and their products of fermentation (organic acids and bacteriocins), as a replacement for antibiotics in stimulating health and growth of broiler chickens. The effects of the supplementation of both preparations (with proven probiotic effect in weaned piglets) and an antibiotic (avilamycin) on body weight gain (BWG), feed intake (FI), feed consumption efficiency (FCE), relative intestinal weight, and intestinal microbiota counts were studied in 1-day posthatch chickens. The experiments were conducted with medium-growth Sasso X44 chickens housed in cages and with nutritional stressed Ross 308 broiler distributed in pens. Consumption of the different diets did not affect significantly the final coliform counts in Sasso X44 chickens. However, counts of lactic acid bacteria and mesophilic microorganisms were higher in the animals receiving the two probiotic preparations (P < 0.05). In the second experiment, although no differences in BWG were observed between treatments, Ross 308 broilers receiving the probiotic Lactobacillus preparation exhibited the lowest FCE values and were considered the most efficient at converting feed into live weight. PMID:22666137

  10. Aminopeptidase activity by spoilage bacteria and its relationship to microbial load and sensory attributes of poultry legs during aerobic cold storage.

    PubMed

    Guevara-Franco, José Alfredo; Alonso-Calleja, Carlos; Capita, Rosa

    2010-02-01

    The shelf life of poultry legs stored aerobically and the possible role of the aminopeptidase activity of gram-negative bacteria (p-nitroaniline test) as a predictor of poultry spoilage were evaluated on the basis of microbiological and sensory parameters. Chicken legs (n = 30) obtained immediately after evisceration in a local poultry processing plant were kept under aerobic refrigeration (4 +/- 1 degrees C) for 7 days. Microbiological (counts of aerobic bacteria and psychrotrophs) and sensory (odor, color, and general acceptability on a hedonic scale of 1 to 9) parameters and aminopeptidase activity (absorbance at 390 nm [A(390)]) determinations were performed after 0, 1, 3, 5, and 7 days of storage. Aerobic plate counts of 7 log CFU/g and a score of 6 for general acceptability were used as indicators of the end point of shelf life. Strong correlations (r > or = 0.76; P < 0.001) were obtained between bacterial counts, hedonic scores, and A(390) values. Samples were judged as unacceptable (shelf-life end point) after 2 and 4 days on the basis of sensory and microbiological analyses, respectively. A(390) values of 0.52 and 0.89 (corresponding to p-nitroaniline concentrations of 6.25 and 10.7 microg/ml, respectively) are proposed as the upper limits for acceptability on the basis of sensory and microbiological determinations, respectively. However, these recommendations are based on a small set of samples, and their general application is yet to be verified. PMID:20132678

  11. Enzyme activities of aerobic lignocellulolytic bacteria isolated from wet tropical forest soils.

    PubMed

    Woo, Hannah L; Hazen, Terry C; Simmons, Blake A; DeAngelis, Kristen M

    2014-02-01

    Lignocellulolytic bacteria have promised to be a fruitful source of new enzymes for next-generation lignocellulosic biofuel production. Puerto Rican tropical forest soils were targeted because the resident microbes decompose biomass quickly and to near-completion. Isolates were initially screened based on growth on cellulose or lignin in minimal media. 75 Isolates were further tested for the following lignocellulolytic enzyme activities: phenol oxidase, peroxidase, ?-d-glucosidase, cellobiohydrolase, ?-xylopyranosidase, chitinase, CMCase, and xylanase. Cellulose-derived isolates possessed elevated ?-d-glucosidase, CMCase, and cellobiohydrolase activity but depressed phenol oxidase and peroxidase activity, while the contrary was true of lignin isolates, suggesting that these bacteria are specialized to subsist on cellulose or lignin. Cellobiohydrolase and phenol oxidase activity rates could classify lignin and cellulose isolates with 61% accuracy, which demonstrates the utility of model degradation assays. Based on 16S rRNA gene sequencing, all isolates belonged to phyla dominant in the Puerto Rican soils, Proteobacteria, Firmicutes, and Actinobacteria, suggesting that many dominant taxa are capable of the rapid lignocellulose degradation characteristic of these soils. The isolated genera Aquitalea, Bacillus, Burkholderia, Cupriavidus, Gordonia, and Paenibacillus represent rarely or never before studied lignolytic or cellulolytic species and were undetected by metagenomic analysis of the soils. The study revealed a relationship between phylogeny and lignocellulose-degrading potential, supported by Kruskal-Wallis statistics which showed that enzyme activities of cultivated phyla and genera were different enough to be considered representatives of distinct populations. This can better inform future experiments and enzyme discovery efforts. PMID:24238986

  12. The determination of the real nano-scale sizes of bacteria in chernozem during microbial succession by means of hatching of a soil in aerobic and anaerobic conditions

    NASA Astrophysics Data System (ADS)

    Gorbacheva, M.

    2012-04-01

    M.A. Gorbacheva,L.M. Polyanskaya The Faculty of Soil Science, Moscow State University, Leninskie Gory, GSP-1, Moscow,119991,Russia In recent years there's been particular attention paid to the smallest life's forms- bacteria which size can be measured in nanometer. These are the forms of bacteria with diameter of 5-200 nm. Theoretical calculations based on the content of the minimum number of DNA, enzyme, lipids in and ribosome in cells indicates impossibility of existence of a living cells within diameter less than 300 nm. It is theoretically possible for a living cell to exist within possible diameter of approximately 140 nm. Using a fluorescence microscope there's been indicated in a number of samples from lakes, rivers, soil, snow and rain water that 200 nm is the smallest diameter of a living cell. Supposingly, such a small size of bacteria in soil is determined by natural conditions which limit their development by nutritious substances and stress-factors. Rejuvenescence of nanobacteria under unfavourable natural conditions and stress-factors is studied in laboratory environment. The object of the current study has become the samples of typical arable chernozem of the Central Chernozem State Biosphere Reserve in Kursk. The detailed morphological description of the soil profile and its basic analytical characteristics are widely represented in scientific publications. The soil is characterized by a high carbon content which makes up 3,96% ,3,8% , and 2,9% for the upper layers of the A horizon, and 0,79% for the layer of the B horizon. A microbial succession was studied under aerobic and anaerobic conditions by means of experiments with microcosms in upper A horizons and B horizon of a chernozem. The final aim is to identify the cells size of bacteria in aerobic and anaerobic soil conditions in chernozem during the microbial succession, by dampening and application of chitin by means of «cascade filtration» method. The study of the microcosms is important for understanding natural mechanisms in soil and will be useful for the development of new soil models in laboratory. Thus, by means of «cascade filtration» method there've been made some results on true size, quantity and biomass of bacteria. Development of a bacteria in various soil horizons and their layers in aerobic and anaerobic conditions and calculations of biomass of bacteria in upper layer horizon A and lower layer horizon B have also become the subjects of the studies. It was identified that the quantity of bacteria in aerobic conditions increase during the microbial succession while bacteria sized 230 and 380 nm were dominating. In anaerobic conditions the process of connecting cells sized 170 nm and bacteria is observed. Biomass of bacteria is higher in anaerobic conditions in upper layer horizon A because of elevated variety of bacteria. In horizon B in anaerobic conditions it is of maximum because of anaerobic situation in situ. Thus, distribution of bacteria's size depends on aeration of soil. That helps to acknowledge the receipt of theory of a great number of researchers about that fact that the size of bacteria in the soil in anaerobic conditions decrease under stress-factors. This work touches upon such a poorly investigated subject as nanobacteria in the soil. But this knowledge plays a significant role in land reclamation oil-cut and prognostication pollution of the soil by pathogenic bacteria.

  13. Halolactibacillus halophilus gen. nov., sp. nov. and Halolactibacillus miurensis sp. nov., halophilic and alkaliphilic marine lactic acid bacteria constituting a phylogenetic lineage in Bacillus rRNA group 1

    Microsoft Academic Search

    Morio Ishikawa; Kazuyuki Nakajima; Yuko Itamiya; Sayumi Furukawa; Yasushi Yamamoto; Kazuhide Yamasato

    2005-01-01

    Eleven novel strains of marine-inhabiting lactic acid bacteria that were isolated from living and decaying marine organisms collected from a temperate area of Japan are described. The isolates were motile with peritrichous flagella and non-sporulating. They lacked catalase, quinones and cytochromes. Fermentation products from glucose were lactate, formate, acetate and ethanol. Lactate yield as percentage conversion from glucose was affected

  14. The Use of MALDI-TOF Mass Spectrometry, Ribotyping and Phenotypic Tests to Identify Lactic Acid Bacteria from Fermented Cereal Foods in Abidjan (Côte d’Ivoire)

    PubMed Central

    Soro-Yao, Amenan A; Schumann, Peter; Thonart, Philippe; Djè, Koffi M; Pukall, Rüdiger

    2014-01-01

    Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) protein analysis, automated ribotyping, and phenotypic tests (e.g., cell morphology, gas production from glucose, growth and acid production on homofermemtative-heterofermentative differential (HHD) agar medium, sugar fermentation patterns) were used to identify 23 lactic acid bacteria (LAB) isolated from fermented cereal foods available in Abidjan, Côte d’Ivoire. Pediococcus acidilactici (56.5%), Lactobacillus fermentum (30.4%), L. salivarius (4.3%), P. pentosaceus (4.3%) and L. plantarum subsp. plantarum (4.3%) were the species and subspecies identified. Protein based identification was confirmed by automated ribotyping for selected isolates and was similar to that provided by the phenotypic characterization. MALDI-TOF MS protein analysis provided a high level of discrimination among the isolates and could be used for the rapid screening of LAB starter cultures. PMID:25279017

  15. The influence of the cell free solution of lactic acid bacteria on tyramine production by food borne-pathogens in tyrosine decarboxylase broth.

    PubMed

    Toy, Nurten; Özogul, Fatih; Özogul, Yesim

    2015-04-15

    The function of cell-free solutions (CFSs) of lactic acid bacteria (LAB) on tyramine and other biogenic amine production by different food borne-pathogens (FBPs) was investigated in tyrosine decarboxylase broth (TDB) using HPLC. Cell free solutions were prepared from four LAB strains. Two different concentrations which were 50% (5 ml CFS+5 ml medium/1:1) and 25% (2.5 ml CFS+7.5 ml medium/1:3) CFS and the control without CFS were prepared. Both concentration of CFS of Streptococcus thermophilus and 50% CFS of Pediococcus acidophilus inhibited tyramine production up to 98% by Salmonella paratyphi A. Tyramine production by Escherichia coli was also inhibited by 50% CFS of Lactococcus lactis subsp. lactis and 25% CFS of Leuconostoc lactis. subsp. cremoris. The inhibitor effect of 50% CFS of P. acidophilus was the highest on tyramine production (55%) by Listeria monocytogenes, following Lc. lactis subsp. lactis and Leuconostoc mesenteroides subsp. cremoris (20%) whilst 25% CFS of Leu. mes. subsp. cremoris and Lc. lactis subsp. lactis showed stimulator effects (160%). The stimulation effects of 50% CFS of S. thermophilus and Lc. lactis subsp. lactis were more than 70% by Staphylococcus aureus comparing to the control. CFS of LAB strains showed statistically inhibitor effect since lactic acid inhibited microbial growth, decreased pH quickly and reduced the formation of AMN and BAs. Consequently, in order to avoid the formation of high concentrations of biogenic amines in fermented food by bacteria, it is advisable to use CFS for food and food products. PMID:25465993

  16. Induction of systemic and mucosal immune response and decrease in Streptococcus pneumoniae colonization by nasal inoculation of mice with recombinant lactic acid bacteria expressing pneumococcal surface antigen A.

    PubMed

    Oliveira, Maria Leonor Sarno; Arêas, Ana Paula Mattos; Campos, Ivana Barros; Monedero, Vicente; Perez-Martínez, Gaspar; Miyaji, Eliane Namie; Leite, Luciana Cezar Cerqueira; Aires, Karina Araújo; Lee Ho, Paulo

    2006-04-01

    Mucosal epithelia constitute the first barriers to be overcome by pathogens during infection. The induction of protective IgA in this location is important for the prevention of infection and can be achieved through different mucosal immunization strategies. Lactic acid bacteria have been tested in the last few years as live vectors for the delivery of antigens at mucosal sites, with promising results. In this work, Streptococcus pneumoniae PsaA antigen was expressed in different species of lactic acid bacteria, such as Lactococcus lactis, Lactobacillus casei, Lactobacillus plantarum, and Lactobacillus helveticus. After nasal inoculation of C57Bl/6 mice, their ability to induce both systemic (IgG in serum) and mucosal (IgA in saliva, nasal and bronchial washes) anti-PsaA antibodies was determined. Immunization with L. lactis MG1363 induced very low levels of IgA and IgG, possibly by the low amount of PsaA expressed in this strain and its short persistence in the nasal mucosa. All three lactobacilli persisted in the nasal mucosa for 3 days and produced a similar amount of PsaA protein (150-250 ng per 10(9) CFU). However, L. plantarum NCDO1193 and L. helveticus ATCC15009 elicited the highest antibody response (IgA and IgG). Vaccination with recombinant lactobacilli but not with recombinant L. lactis led to a decrease in S. pneumoniae recovery from nasal mucosa upon a colonization challenge. Our results confirm that certain Lactobacillus strains have intrinsic properties that make them suitable candidates for mucosal vaccination experiments. PMID:16549380

  17. Comparison of the BACTEC MYCO\\/F Lytic Bottle to the Isolator Tube, BACTEC Plus Aerobic F\\/Bottle, and BACTEC Anaerobic Lytic\\/10 Bottle and Comparison of the BACTEC Plus Aerobic F\\/Bottle to the Isolator Tube for Recovery of Bacteria, Mycobacteria, and Fungi from Blood

    Microsoft Academic Search

    E. Vetter; C. Torgerson; A. Feuker; J. Hughes; S. Harmsen; C. Schleck; C. Horstmeier; G. Roberts; F. Cockerill

    2001-01-01

    The BACTEC MYCO\\/F Lytic blood culture bottle (Becton Dickinson Diagnostic Instrument Systems, Sparks, Md.) is designed to optimize the recovery of fungi and mycobacteria; however, this bottle also supports the growth of most aerobic bacteria. We compared the MYCO\\/F Lytic bottle with two other BACTEC bottles and the Isolator system for the recovery of bacteria as well as fungi and

  18. Phenotypic identification and technological attributes of native lactic acid bacteria present in fermented bamboo shoot products from North-East India.

    PubMed

    Sonar, Nitin R; Halami, Prakash M

    2014-12-01

    Fermented bamboo shoots such as Soibum, Soidon, Eup, Hirring, Hecche and Ekung etc. are non-salted acidic products obtained by natural fermentation predominantly with lactic acid bacteria (LAB). In this study, we have characterized 11-representative LAB that includes, Lactobacillus sp. (n?=?2), Lactobacillus plantarum (n?=?3), and one each of Lactobacillus fermentum, Lactococcus sp., Lactobacillus brevis, Lactobacillus curvatus, Leuconostoc sp. and Lactobacillus xylosus. Subsequently, these cultures were studied for their technological and functional properties. Different isolates exhibited variation in their activities. L. brevis showed maximum phytic acid degradation ability (19.33 U ml (-1) ). L. xylosus had highest protease activity (64.2 nmol/ml) and also exhibited lipolytic activity. In addition, degree of cell hydrophobicity among these cultures ranged between 12.5 and 93.48 % with L. plantarum (SM2) showing highest degree of activity. Lactobacillus plantarum was the most common species found in the product studied. Results indicated that most of the LABs showed putative probiotic as well as antagonistic properties against the selected pathogenic bacteria. Characteristic aroma, flavour and texture in the fermented bamboo shoot products could be attributed to presence of these new LAB isolates. PMID:25477695

  19. Influence of Turning and Environmental Contamination on the Dynamics of Populations of Lactic Acid and Acetic Acid Bacteria Involved in Spontaneous Cocoa Bean Heap Fermentation in Ghana?

    PubMed Central

    Camu, Nicholas; González, Ángel; De Winter, Tom; Van Schoor, Ann; De Bruyne, Katrien; Vandamme, Peter; Takrama, Jemmy S.; Addo, Solomon K.; De Vuyst, Luc

    2008-01-01

    The influence of turning and environmental contamination on six spontaneous cocoa bean heap fermentations performed in Ghana was studied through a multiphasic approach, encompassing both microbiological (culture-dependent and culture-independent techniques) and metabolite target analyses. A sensory analysis of chocolate made from the fermented, dried beans was performed as well. Only four clusters were found among the isolates of acetic acid bacteria (AAB) identified: Acetobacter pasteurianus, Acetobacter ghanensis, Acetobacter senegalensis, and a potential new Acetobacter lovaniensis-like species. Two main clusters were identified among the lactic acid bacteria (LAB) isolated, namely, Lactobacillus plantarum and Lactobacillus fermentum. No differences in biodiversity of LAB and AAB were seen for fermentations carried out at the farm and factory sites, indicating the cocoa pod surfaces and not the general environment as the main inoculum for spontaneous cocoa bean heap fermentation. Turning of the heaps enhanced aeration and increased the relative population size of AAB and the production of acetic acid. This in turn gave a more sour taste to chocolate made from these beans. Bitterness was reduced through losses of polyphenols and alkaloids upon fermentation and cocoa bean processing. PMID:17993565

  20. Isolation of Bacillus sp. strains capable of decomposing alkali lignin and their application in combination with lactic acid bacteria for enhancing cellulase performance.

    PubMed

    Chang, Young-Cheol; Choi, Dubok; Takamizawa, Kazuhiro; Kikuchi, Shintaro

    2014-01-01

    Effective biological pretreatment method for enhancing cellulase performance was investigated. Two alkali lignin-degrading bacteria were isolated from forest soils in Japan and named CS-1 and CS-2. 16S rDNA sequence analysis indicated that CS-1 and CS-2 were Bacillus sp. Strains CS-1 and CS-2 displayed alkali lignin degradation capability. With initial concentrations of 0.05-2.0 g L(-1), at least 61% alkali lignin could be degraded within 48 h. High laccase activities were observed in crude enzyme extracts from the isolated strains. This result indicated that alkali lignin degradation was correlated with laccase activities. Judging from the net yields of sugars after enzymatic hydrolysis, the most effective pretreatment method for enhancing cellulase performance was a two-step processing procedure (pretreatment using Bacillus sp. CS-1 followed by lactic acid bacteria) at 68.6%. These results suggest that the two-step pretreatment procedure is effective at accelerating cellulase performance. PMID:24316485