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Nagendra P Shah - One of the best experts on this subject based on the ideXlab platform.
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chemical analysis and sensory evaluation of cheddar cheese produced with Lactobacillus acidophilus lb casei lb paracasei or bifidobacterium sp
International Dairy Journal, 2007Co-Authors: Lydia Ong, Anders Henriksson, Nagendra P ShahAbstract:The sensory properties of probiotic Cheddar cheeses made using Lactobacillus acidophilus 4962, Lb. casei 279, Bifidobacterium longum 1941, Lb. acidophilus LAFTI® L10, Lb. paracasei LAFTI® L26 or B. lactis LAFTI® B94 were assessed after ripening for 9 months at 4°C. Probiotic cheeses except those with Lb. acidophilus 4962 were significantly different (P 0.05). Increased proteolysis in probiotic cheeses did not influence the Cheddary attribute scores (P>0.05). There were positive correlations (P<0.05) between the scores of bitterness and the level of water-soluble nitrogen.
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evaluation of enzymic potential for biotransformation of isoflavone phytoestrogen in soymilk by bifidobacterium animalis Lactobacillus acidophilus and Lactobacillus casei
Food Research International, 2006Co-Authors: Daniel O Otieno, John Ashton, Nagendra P ShahAbstract:Abstract Three strains of Lactobacillus acidophilus, two of Lactobacillus casei and one of Bifidobacterium were screened for β-glucosidase activity using ρ-nitrophenyl-β- d -glucopyranoside as a substrate and their potential for the breakdown of isoflavone glucosides to the biologically active aglycones in soymilk. Isoflavones quantification with HPLC and β-glucosidase activity were performed after 0, 12, 24, 36, and 48 h of incubation in soymilk at 37 °C. All six micro-organisms produced β-glucosidase, which hydrolysed the predominant isoflavone β-glucosides. There was a significant increase and decrease (P
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production of organic acids from fermentation of mannitol fructooligosaccharide and inulin by a cholesterol removing Lactobacillus acidophilus strain
Journal of Applied Microbiology, 2005Co-Authors: Mintze Liong, Nagendra P ShahAbstract:ABSTRACT M.T. LIONG AND N.P. SHAH. 2005. Aims: Assessment of individual production of organic acids by Lactobacillus acidophilus ATCC 4962 in thepresence of mannitol, fructooligosaccharide (FOS) and inulin.Methods and Results: The production patterns of individual organic acids by L. acidophilus ATCC 4962were assessed using the experimental region for optimum cholesterol removal from the interaction betweenL. acidophilus ATCC 4962 and prebiotics selected in our previous study. The production of acetic and formicacids was growth associated and was greatly influenced by the inoculum size of the organism and the concentra-tion of mannitol. The growth of the organism was repressed with the fermentation end products of FOS andinulin, which subsequently exhibited repressed production of acetic and formic acids as well. The inoculum size,mannitol and FOS linearly affected the formation of butyric acid and the response surface generated showed acorrelation between butyric acid and acetic acid. The experimental regions with increased production of lactic acidshowed cessation of growth of the organism, indicating inhibition of growth at high concentration of lactic acid.Conclusions: The production of individual organic acids was dependent on growth and the fermentability ofprebiotics. Mannitol, FOS and inulin favoured the production of formic, lactic and butyric acids respectively.Significance and Impact of the Study: The fermentability of prebiotics to produce metabolites has been acontroversial issue. Information gathered in this study provides a better understanding on the production of organicacids from fermentation of mannitol, FOS and inulin by L. acidophilus ATCC 4962, and on changes in theirproduction as a response from interaction of factors.Keywords: fructooligosaccharide, inulin, Lactobacillus acidophilus, mannitol, short-chain fatty acid.
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survival of Lactobacillus acidophilus and bifidobacterium bifidum in commercial yoghurt during refrigerated storage
International Dairy Journal, 1995Co-Authors: Nagendra P Shah, W E V Lankaputhra, M L Britz, William S A KyleAbstract:Abstract Samples of five brands of commercial yoghurt were obtained directly from the processors and enumeration of viable Lactobacillus acidophilus and Bifidobacterium bifidum and determination of pH was carried out at three-day intervals over a five-week period. Three of the five products contained 10 7 –10 8 g −1 viable cells of L. acidophilus , whereas the other two products contained ⩽ 10 5 of this organism initially. Similarly, the initial count of B. bifidum was 10 6 –10 7 g −1 in two of five products, while the viable numbers of this organism were ⩽ 10 3 in the other three products. All the products showed a constant decline in the viable count of L. acidophilus and B. bifidum during storage. Initial pH values ranged from 4.07 to 4.36 and these declined after five weeks of storage to pH 3.8–4.26.
Todd R Klaenhammer - One of the best experts on this subject based on the ideXlab platform.
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an extracellular cell attached pullulanase confers branched α glucan utilization in human gut Lactobacillus acidophilus
Applied and Environmental Microbiology, 2017Co-Authors: Marie Sofie Moller, Todd R Klaenhammer, Yong Jun Goh, Kasper Bowig Rasmussen, Wojciech Cypryk, Hasan Ufuk Celebioglu, Birte Svensson, Maher Abou HachemAbstract:Of the few predicted extracellular glycan-active enzymes, glycoside hydrolase family 13 subfamily 14 (GH13_14) pullulanases are the most common in human gut lactobacilli. These enzymes share a unique modular organization, not observed in other bacteria, featuring a catalytic module, two starch binding modules, a domain of unknown function, and a C-terminal surface layer association protein (SLAP) domain. Here, we explore the specificity of a representative of this group of pullulanases, Lactobacillus acidophilus Pul13_14 (LaPul13_14), and its role in branched α-glucan metabolism in the well-characterized Lactobacillus acidophilus NCFM, which is widely used as a probiotic. Growth experiments with L. acidophilus NCFM on starch-derived branched substrates revealed a preference for α-glucans with short branches of about two to three glucosyl moieties over amylopectin with longer branches. Cell-attached debranching activity was measurable in the presence of α-glucans but was repressed by glucose. The debranching activity is conferred exclusively by LaPul13_14 and is abolished in a mutant strain lacking a functional LaPul13_14 gene. Hydrolysis kinetics of recombinant LaPul13_14 confirmed the preference for short-branched α-glucan oligomers consistent with the growth data. Curiously, this enzyme displayed the highest catalytic efficiency and the lowest Km reported for a pullulanase. Inhibition kinetics revealed mixed inhibition by β-cyclodextrin, suggesting the presence of additional glucan binding sites besides the active site of the enzyme, which may contribute to the unprecedented substrate affinity. The enzyme also displays high thermostability and higher activity in the acidic pH range, reflecting adaptation to the physiologically challenging conditions in the human gut.IMPORTANCE Starch is one of the most abundant glycans in the human diet. Branched α-1,6-glucans in dietary starch and glycogen are nondegradable by human enzymes and constitute a metabolic resource for the gut microbiota. The role of health-beneficial lactobacilli prevalent in the human small intestine in starch metabolism remains unexplored in contrast to colonic bacterial residents. This study highlights the pivotal role of debranching enzymes in the breakdown of starchy branched α-glucan oligomers (α-limit dextrins) by human gut lactobacilli exemplified by Lactobacillus acidophilus NCFM, which is one of the best-characterized strains used as probiotics. Our data bring novel insight into the metabolic preference of L. acidophilus for α-glucans with short α-1,6-branches. The unprecedented affinity of the debranching enzyme that confers growth on these substrates reflects its adaptation to the nutrient-competitive gut ecological niche and constitutes a potential advantage in cross-feeding from human and bacterial dietary starch metabolism.
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Transcriptional Analysis of Prebiotic Uptake and Catabolism by Lactobacillus acidophilus NCFM
2016Co-Authors: Joakim Mark Andersen, Yong Jun Goh, Birte Svensson, Maher Abou Hachem, Rodolphe Barrangou, Sampo J. Lahtinen, Todd R KlaenhammerAbstract:The human gastrointestinal tract can be positively modulated by dietary supplementation of probiotic bacteria in combination with prebiotic carbohydrates. Here differential transcriptomics and functional genomics were used to identify genes in Lactobacillus acidophilus NCFM involved in the uptake and catabolism of 11 potential prebiotic compounds consisting of a- and b- linked galactosides and glucosides. These oligosaccharides induced genes encoding phosphoenolpyruvate-dependent sugar phosphotransferase systems (PTS), galactoside pentose hexuronide (GPH) permease, and ATP-binding cassette (ABC) transporters. PTS systems were upregulated primarily by di- and tri-saccharides such as cellobiose, isomaltose, isomaltulose, panose and gentiobiose, while ABC transporters were upregulated by raffinose, Polydextrose, and stachyose. A single GPH transporter was induced by lactitol and galactooligosaccharides (GOS). Th
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abating colon cancer polyposis by Lactobacillus acidophilus deficient in lipoteichoic acid
Proceedings of the National Academy of Sciences of the United States of America, 2012Co-Authors: Khashayarsha Khazaie, Mohammad W. Khan, Mojgan Zadeh, Praveen Bere, Jennifer L. Owen, Fotini Gounari, Kirsten Dennis, Nichole R Blatner, Todd R KlaenhammerAbstract:An imbalance of commensal bacteria and their gene products underlies mucosal and, in particular, gastrointestinal inflammation and a predisposition to cancer. Lactobacillus species have received considerable attention as examples of beneficial microbiota. We have reported previously that deletion of the phosphoglycerol transferase gene that is responsible for lipoteichoic acid (LTA) biosynthesis in Lactobacillus acidophilus (NCK2025) rendered this bacterium able to significantly protect mice against induced colitis when delivered orally. Here we report that oral treatment with LTA-deficient NCK2025 normalizes innate and adaptive pathogenic immune responses and causes regression of established colonic polyps. This study reveals the proinflammatory role of LTA and the ability of LTA-deficient L. acidophilus to regulate inflammation and protect against colonic polyposis in a unique mouse model.
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lipoteichoic acid deficient Lactobacillus acidophilus regulates downstream signals
Immunotherapy, 2011Co-Authors: Rana Saber, Todd R Klaenhammer, Mojgan Zadeh, Praveen Bere, Krishna Chaitanya Pakanati, Mansour MohamadzadehAbstract:The trillions of microbes residing within the intestine induce critical signals that either regulate or stimulate host immunity via their bacterial products. To better understand the immune regulation elicited by lipoteichoic acid (LTA)-deficient Lactobacillus acidophilus NCFM in steady state and induced inflammation, we deleted phosphoglycerol transferase gene, which synthesizes LTA in L. acidophilus NCFM. In vitro and in vivo experiments were conducted in order to compare the immune regulatory properties of the L. acidophilus strain deficient in LTA (NCK2025) with its wild-type parent (NCK56) in C57BL/6, C57BL/6 recombination-activation gene 1-deficient (Rag1 -/-) and C57BL/6 Rag1-/-IL-10-/- mice. We demonstrate that NCK2025 significantly activates the phosphorylation of Erk1/2 but downregulates the phosphorylation of Akt1, cytosolic group IV PLA2 and p38 in mouse dendritic cells. Similarly, mice treated orally with NCK2025 exhibit decreased phosphorylation of inflammatory signals (Akt1, cytosolic group...
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efficient system for directed integration into the Lactobacillus acidophilus and Lactobacillus gasseri chromosomes via homologous recombination
Applied and Environmental Microbiology, 2001Co-Authors: William M Russell, Todd R KlaenhammerAbstract:An efficient method is described for the generation of site-specific chromosomal integrations in Lactobacillus acidophilus and Lactobacillus gasseri. The strategy is an adaptation of the lactococcal pORI system (K. Leenhouts, G. Venema, and J. Kok, Methods Cell Sci. 20:35–50, 1998) and relies on the simultaneous use of two plasmids. The functionality of the integration strategy was demonstated by the insertional inactivation of the Lactobacillus acidophilus NCFM lacL gene encoding β-galactosidase and of the Lactobacillus gasseri ADH gusA gene encoding β-glucuronidase.
Jagoda Suskovic - One of the best experts on this subject based on the ideXlab platform.
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importance of s layer proteins in probiotic activity of Lactobacillus acidophilus m92
Journal of Applied Microbiology, 2005Co-Authors: Jadranka Frece, Blaženka Kos, Ivankresimir Svetec, Zoran Zgaga, Vladimir Mrsa, Jagoda SuskovicAbstract:J. FRECE, B. KOS, I.K. SVETEC, Z. ZGAGA, V. MRSAA ND J. SUSKOVIC´ . 2004. Aims: To investigate the functional role of surface layer proteins (S-layer) in probiotic strain Lactobacillus acidophilus M92, especially its influence on adhesiveness to mouse ileal epithelial cells. Methods and Results: Sodium dodecyl sulphate polyacrylamide gel electrophoresis of cell surface proteins revealed the presence of potential surface layer (S-layer) proteins, ca at 45 kDa in L. acidophilus M92. Southern blot with pBK1 plasmid, containing slpA gene, gave a positive signal, suggesting that L. acidophilus M92 has a slpA gene coding for the S-layer proteins. S-layer proteins of this strain are present during all phases of growth. The S-layer proteins appeared when cells treated with 5 mol l )1 LiCl were allowed to grow again. Removal of the S-layer proteins reduced adhesion of L. acidophilus M92 to mouse ileal epithelial cells. Furthermore, the viability of cells without S-layer were reduced in simulated gastric juice at low pH range (2, 2AE5, 3) and simulated pancreatic juice with bile salts (1AE 5a nd 3gl )1 ). S-layer proteins of L. acidophilus M92 were resistant to pepsin and pancreatin, in contrast, the treatment with proteinase K led to a significant proteolysis of the S-layer proteins. Conclusions: These results demonstrated functional role of S-layer; it is responsible for adhesiveness of Lactobacillus acidophilus M92 to mouse ileal epithelial cells and has a protective role for this strain. Significance and Impact of the Study: S-layer proteins have an important role in the establishment of probiotic strain Lactobacillus acidophilus M92 in the gastrointestinal tract.
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adhesion and aggregation ability of probiotic strain Lactobacillus acidophilus m92
Journal of Applied Microbiology, 2003Co-Authors: Jagoda Suskovic, Jadranka Frece, Snježana Vukovic, Miljenko Simpraga, Srecko MatosicAbstract:B. K OS, J. SUSKOVIC ´ ,S. V U K O V I C´ ,M. SIMPRAGA, J. F RECE A ND S. M ATOSIC ´ . 2003. Aims: To investigate aggregation and adhesiveness of Lactobacillus acidophilus M92 to porcine ileal epithelial cells in vitro, and the influence of cell surface proteins on autoaggregation and adhesiveness of this strain. Methods and Results: Lactobacillus acidophilus M92 exhibits a strong autoaggregating phenotype and manifests a high degree of hydrophobicity determined by microbial adhesion to xylene. Aggregation and hydrophobicity were abolished upon exposure of the cells to pronase and pepsin. Sodium dodecyl sulphate polyacrylamide gel electrophoresis of cell surface proteins revealed the presence of potential surface layer (S-layer) proteins, approximated at 45 kDa, in L. acidophilus M92. The relationship between autoaggregation and adhesiveness to intestinal tissue was investigated by observing the adhesiveness of L. acidophilus M92 to porcine ileal epithelial cells. Removal of the S-layer proteins by extraction with 5 mol l )1 LiCl reduced autoaggregation and in vitro adhesion of this strain. Conclusions: These results demonstrate that there is relationship between autoaggregation and adhesiveness ability of L. acidophilus M92, mediated by proteinaceous components on the cell surface. Significance and Impact of the Study: This investigation has shown that L. acidophilus M92 has the ability to establish in the human gastrointestinal tract, which is an important determinant in the choice of probiotic strains.
Jadranka Frece - One of the best experts on this subject based on the ideXlab platform.
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importance of s layer proteins in probiotic activity of Lactobacillus acidophilus m92
Journal of Applied Microbiology, 2005Co-Authors: Jadranka Frece, Blaženka Kos, Ivankresimir Svetec, Zoran Zgaga, Vladimir Mrsa, Jagoda SuskovicAbstract:J. FRECE, B. KOS, I.K. SVETEC, Z. ZGAGA, V. MRSAA ND J. SUSKOVIC´ . 2004. Aims: To investigate the functional role of surface layer proteins (S-layer) in probiotic strain Lactobacillus acidophilus M92, especially its influence on adhesiveness to mouse ileal epithelial cells. Methods and Results: Sodium dodecyl sulphate polyacrylamide gel electrophoresis of cell surface proteins revealed the presence of potential surface layer (S-layer) proteins, ca at 45 kDa in L. acidophilus M92. Southern blot with pBK1 plasmid, containing slpA gene, gave a positive signal, suggesting that L. acidophilus M92 has a slpA gene coding for the S-layer proteins. S-layer proteins of this strain are present during all phases of growth. The S-layer proteins appeared when cells treated with 5 mol l )1 LiCl were allowed to grow again. Removal of the S-layer proteins reduced adhesion of L. acidophilus M92 to mouse ileal epithelial cells. Furthermore, the viability of cells without S-layer were reduced in simulated gastric juice at low pH range (2, 2AE5, 3) and simulated pancreatic juice with bile salts (1AE 5a nd 3gl )1 ). S-layer proteins of L. acidophilus M92 were resistant to pepsin and pancreatin, in contrast, the treatment with proteinase K led to a significant proteolysis of the S-layer proteins. Conclusions: These results demonstrated functional role of S-layer; it is responsible for adhesiveness of Lactobacillus acidophilus M92 to mouse ileal epithelial cells and has a protective role for this strain. Significance and Impact of the Study: S-layer proteins have an important role in the establishment of probiotic strain Lactobacillus acidophilus M92 in the gastrointestinal tract.
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adhesion and aggregation ability of probiotic strain Lactobacillus acidophilus m92
Journal of Applied Microbiology, 2003Co-Authors: Jagoda Suskovic, Jadranka Frece, Snježana Vukovic, Miljenko Simpraga, Srecko MatosicAbstract:B. K OS, J. SUSKOVIC ´ ,S. V U K O V I C´ ,M. SIMPRAGA, J. F RECE A ND S. M ATOSIC ´ . 2003. Aims: To investigate aggregation and adhesiveness of Lactobacillus acidophilus M92 to porcine ileal epithelial cells in vitro, and the influence of cell surface proteins on autoaggregation and adhesiveness of this strain. Methods and Results: Lactobacillus acidophilus M92 exhibits a strong autoaggregating phenotype and manifests a high degree of hydrophobicity determined by microbial adhesion to xylene. Aggregation and hydrophobicity were abolished upon exposure of the cells to pronase and pepsin. Sodium dodecyl sulphate polyacrylamide gel electrophoresis of cell surface proteins revealed the presence of potential surface layer (S-layer) proteins, approximated at 45 kDa, in L. acidophilus M92. The relationship between autoaggregation and adhesiveness to intestinal tissue was investigated by observing the adhesiveness of L. acidophilus M92 to porcine ileal epithelial cells. Removal of the S-layer proteins by extraction with 5 mol l )1 LiCl reduced autoaggregation and in vitro adhesion of this strain. Conclusions: These results demonstrate that there is relationship between autoaggregation and adhesiveness ability of L. acidophilus M92, mediated by proteinaceous components on the cell surface. Significance and Impact of the Study: This investigation has shown that L. acidophilus M92 has the ability to establish in the human gastrointestinal tract, which is an important determinant in the choice of probiotic strains.
Alain L Servin - One of the best experts on this subject based on the ideXlab platform.
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antibacterial effect of the adhering human Lactobacillus acidophilus strain lb
Antimicrobial Agents and Chemotherapy, 1997Co-Authors: Mariehelene Coconnier, Vanessa Lievin, Mariefrancoise Bernetcamard, S Hudault, Alain L ServinAbstract:The spent culture supernatant of the human Lactobacillus acidophilus strain LB produces an antibacterial activity against a wide range of gram-negative and gram-positive pathogens. It decreased the in vitro viability of Staphylococcus aureus, Listeria monocytogenes, Salmonella typhimurium, Shigella flexneri, Escherichia coli, Klebsiella pneumoniae, Bacillus cereus, Pseudomonas aeruginosa, and Enterobacter spp. In contrast, it did not inhibit lactobacilli and bifidobacteria. The activity was heat stable and relatively sensitive to enzymatic treatments and developed under acidic conditions. The antimicrobial activity was independent of lactic acid production. Activity against S. typhimurium SL1344 infecting human cultured intestinal Caco-2 cells was observed as it was in the conventional C3H/He/oujco mouse model with S. typhimurium C5 infection and oral treatment with the LB spent culture supernatant.
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adhesion of human Lactobacillus acidophilus strain lb to human enterocyte like caco 2 cells
Microbiology, 1992Co-Authors: Gilles Chauviere, Mariehelene Coconnier, Sophie Kerneis, Jacky Fourniat, Alain L ServinAbstract:Twenty-five strains of lactobacilli were tested for their ability to adhere to human enterocyte-like Caco-2 cells in culture. Seven Lactobacillus strains adhered well to the Caco-2 cells, of which three possessed calcium-independent adhesion properties. A high level of calcium-independent adhesion was observed with the human stool isolate Lactobacillus acidophilus strain LB. Scanning electron microscopy revealed that this strain adhered to the apical brush border of the cells. Adhesion increased in parallel with the morphological and functional differentiation of the Caco-2 cells. Two Lactobacillus components were involved in this adhesion. One was protease-resistant and bacterial-surface-associated; the other was heat-stable, extracellular and protease-sensitive.
