Bile Salt Hydrolase Activity Research Articles

Interpersonal Gut Microbiome Variation Drives Susceptibility and Resistance to Cholera Infection

The gut microbiome is the resident microbial community of the gastrointestinal tract. This community is highly diverse, but how microbial diversity confers resistance or susceptibility to intestinal pathogens is poorly understood. Using transplantation of human microbiomes into several animal models of infection, we show that key microbiome species shape the chemical environment of the gut through the activity of the enzyme bile salt hydrolase. The activity of this enzyme reduced colonization by the major human diarrheal pathogen Vibrio cholerae by degrading the bile salt taurocholate that activates the expression of virulence genes. The absence of these functions and species permits increased infection loads on a personal microbiome-specific basis. These findings suggest new targets for individualized preventative strategies of V.cholerae infection through modulating the structure and function of the gut microbiome.

Bile salt hydrolase activity, growth characteristics and surface properties in Lactobacillus acidophilus

Thirteen strains of Lactobacillus acidophilus of various origins were tested for bile salt hydrolase (BSH) activity, growth characteristics and surface properties during cultivation in the presence of ox bile. Seven strains were BSH positive, three strains were found to hydrolyse both sodium glycocholate and taurocholate and four hydrolysed only glycocholate. The addition of ox bile (3; 5 or 10 g/l) to MRS growth medium affected the growth rate of both BSH-positive and BSH-negative strains. The lag phases were increased when 5 or 10 g/l of ox bile were added. Growth rates and lag phases were significantly different between BSH-positive and BSH-negative strains in MRS medium with bile. BSH-positive strains were better able to adapt to increasing bile concentrations. The concentration of 2 g/l sodium cholate completely inhibited growth of all lactobacilli tested. Its toxicity was influenced by pH of medium. The addition of 3 g/l ox bile affected the properties related to ability of lactobacilli to adhere to surfaces––autoaggregation increased in all strains and zeta potential only in BSH-negative strains. In all strains tested, bshA and bshB genes were identified with the exception of L. acidophilus Lafti-L10. Repeated cultivation in MRS with bile did not cause the expression of genes in BSH-negative strains.

Comprehensive in silico analysis of lactic acid bacteria for the selection of desirable probiotics

In this study, the probiotic properties of nine lactic acid bacteria (LAB) were evaluated by using an in silico analysis comprising principal component, heat map, and network analyses. Acid and bile resistances, bile salt hydrolase (BSH) activity, antimicrobial activity, auto- and co-aggregation, and hydrophobicity were analyzed in the strains. All tested LAB exhibited >60% of survival percentage in acid and bile resistances. Five strains of LAB exhibited positive BSH activities and all LAB demonstrated antimicrobial activities against at least one pathogen except L. acidophilus IDCC3302. Following a time-dependent manner, L. acidophilus IDCC3302 and L. plantarum LP-K1791 exhibited the greatest auto- and co-aggregation percentages, respectively. The hydrophobicity of all LAB was satisfied with the minimum requirement of hydrophobicity (40%) as potential probiotics. Based on the in silico analysis, L. casei IDCC3451, L. plantarum LP-K1791, and L. rhamnosus IDCC3201 were selected as the most promising probiotics. This in silico analysis will be useful for the precise selection of probiotics for the development of functional foods and healthy dietary supplements in the food and pharmaceutical industries.

A human-origin probiotic cocktail ameliorates aging-related leaky gut and inflammation via modulating the microbiota/taurine/tight junction axis.

Inflammation is a major risk factor of morbidity and mortality in older adults. Although its precise etiology is unknown, low-grade inflammation in older adults is commonly associated with increased intestinal epithelial permeability (leaky gut) and abnormal (dysbiotic) gut microbiota. The increasing older population and lack of treatments to reduce aging-related microbiota dysbiosis, leaky gut, and inflammation culminates in a rise in aging-related comorbidities, constituting a significant public health concern. Here, we demonstrate that a human-origin probiotic cocktail containing 5 Lactobacillus and 5 Enterococcus strains isolated from healthy infant gut prevented high-fat diet-induced (HFD-induced) microbiota dysbiosis, leaky gut, inflammation, metabolic dysfunctions, and physical function decline in older mice. Probiotic-modulated gut microbiota primarily reduced leaky gut by increasing tight junctions, which in turn reduced inflammation. Mechanistically, probiotics modulated microbiota in a way to increase bile salt hydrolase activity, which in turn increased taurine abundance in the gut that stimulated tight junctions and suppressed gut leakiness. Furthermore, in Caenorhabditis elegans, taurine increased life span, reduced adiposity and leaky gut, and enhanced physical function. The results suggest that such probiotic therapies could prevent or treat aging-related leaky gut and inflammation in the elderly.

Multifarious cholesterol lowering potential of lactic acid bacteria equipped with desired probiotic functional attributes.

Lactic acid bacteria (LAB) isolates possessed functional probiotic attributes, such as high hydrophobicity and autoaggregation ability, coaggregation capability with bacterial pathogens, antimicrobial activity, antioxidant potential, and hypocholesterolemic effects. Selected potential probiotic LAB, i.e. Lactobacillus paracasei M3, L. casei M5, L. paracasei M7, and few others were studied for their ability to lower cholesterol using a number of methods viz. cholesterol assimilation, bile salt deconjugation, cholesterol co-precipitation, cholesterol adhesion to probiotic cell wall, and miceller sequestration of cholesterol. L. casei M5 showed maximum bile salt hydrolase (BSH) activity, and released 57.63nmol of glycine/min, and was closely followed by LAB isolate M9 which generated 52.12nmol of glycine/min. Sodium glycocholate was deconjugated by L. casei M5 to produce 27.77μmol/mL of cholic acid, while other isolates produced 20-26μmol/mL of cholic acid. Cholesterol was assimilated significantly by isolate M6 (82.15%) and L. casei M5 (76.51%). L. casei M5 showed higher cholesterol co-precipitation ability (50.16μg/mL) as compared to other LAB isolates (33-44μg/mL). Miceller cholesterol concentration was reduced maximally byLAB isolate M8 (87.5%), followed by isolates M5 (84.75%), M9 (84%), M10 (80%), and M37 (79%). Higher cell wall adhesion of cholesterol was realized by L. casei M5 (42.48μg/mL) than other LAB isolates (30-40μg/mL). Selected LAB probiotics demonstrated short chain fatty acid (acetate, propionate, and butyrate) producing ability, yet another way of probiotics-mediated cholesterol lowering.

Evaluation of bile salt hydrolase inhibitor efficacy for modulating host bile profile and physiology using a chicken model system

Gut microbial enzymes, bile salt hydrolases (BSHs) are the gateway enzymes for bile acid (BA) modification in the gut. This activity is a promising target for developing innovative non-antibiotic growth promoters to enhance animal production and health. Compelling evidence has shown that inhibition of BSH activity should enhance weight gain by altering the BA pool, host signalling and lipid metabolism. We recently identified a panel of promising BSH inhibitors. Here, we address the potential of them as alternative, effective, non-antibiotic feed additives, for commercial application, to promote animal growth using a chicken model. In this study, the in vivo efficacy of three BSH inhibitors (caffeic acid phenethylester, riboflavin, carnosic acid) were evaluated. 7-day old chicks (10 birds/group) were either untreated or they received one of the specific BSH inhibitors (25 mg/kg body weight) via oral gavage for 17 days. The chicks in treatment groups consistently displayed higher body weight gain than the untreated chicks. Metabolomic analysis demonstrated that BSH inhibitor treatment led to significant changes in both circulating and intestinal BA signatures in support of blunted intestinal BSH activity. Consistent with this finding, liver and intestinal tissue RNA-Seq analysis showed that carnosic acid treatment significantly altered expression of genes involved in lipid and bile acid metabolism. Taken together, this study validates microbial BSH activity inhibition as an alternative target and strategy to antibiotic treatment for animal growth promotion.

Some probiotic potential of Weissella confusa MD1 and Weissella cibaria MD2 isolated from fermented batter

This study was conducted to evaluate the probiotic potential of Weissella confusa MD1 and Weissella cibaria MD2 isolated from a fermented batter. They possessed characters like high survivability in gastrointestinal conditions, tolerance towards lysozyme and phenol. Both strains exhibited strong auto-aggregation property and co-aggregation with Listeria monocytogenes. The adhesion behavior towards intestinal epithelial cells (HT-29 cells) was observed by scanning electron microscopy (SEM). Both strains MD1 and MD2 exhibited antimicrobial activity against foodborne pathogens like Escherichia coli, Salmonella enterica, Listeria monocytogenes, Salmonella typhi and Staphyloccocus aureus. They also showed high bile salt hydrolase activity towards sodium taurocholate and bile salt mixture. Strain MD1 and MD2 demonstrated a tremendous reduction in the cholesterol by 67.11% and 78%, respectively. The intact cells of both strains showed strong antioxidant activity by scavenging 1,1-diphenyl-2-picryl-hydrazyl (DPPH) free radical and inhibition of linoleic acid peroxidation. The formation of biofilm was demonstrated by using atomic force microscopy (AFM) on the glass cover. Both strains showed sensitivity towards conventionally used antibiotics and no hemolytic activity. The results from the study suggested that Weissella confusa MD1 and Weissella cibaria MD2 have exemplary technological properties that can be implemented in the pharmaceutical and food industry.

Intestinal flora imbalance affects bile acid metabolism and is associated with gallstone formation

BackgroundThe gut microbiota participates in the metabolism of substances and energy, promotes the development and maturation of the immune system, forms the mucosal barrier, and protects the host from pathogen attacks. Although the pathogenesis of cholesterol gallstones is still not clear, studies have suggested that gut microbiota dysbiosis plays an important role in their formation.MethodsMicrobial DNA from faeces of normal control patients and those of patients with calculi was subjected to 16S rRNA gene sequencing to detect gene expression changes in intestinal microbes. ELISA kits were used to measure free bile acids, secondary bile acids and coprostanol according to the manufacturer’s instructions. The relationship between flora and their metabolites was then analysed.ResultsIn the gallstone group, the diversity of intestinal bacteria and the abundances of certain phylogroups were significantly decreased (p < 0.05), especially Firmicutes (p < 0.05), the largest phylum represented by the gut microbiota. This study found an increase in free bile acids (p < 0.001) and secondary bile acids (p < 0.01) in the enterohepatic circulation. Bile salt hydrolase activity was not related to the abundances of BSH-active bacteria. 7a-dehydroxylating gut bacteria were significantly increased (p < 0.01), whereas cholesterol-lowering bacteria were significantly reduced (p < 0.05). The Ruminococcus gnavus group could be used as a biomarker to distinguish the gallstone group from the control group.ConclusionWe conclude that intestinal flora imbalance affects bile acid and cholesterol metabolism and is associated with gallstone formation.

Ursodeoxycholic acid enriches intestinal bile salt hydrolase-expressing Bacteroidetes in cholestatic pregnancy

Ursodeoxycholic acid (UDCA) treatment can reduce itch and lower endogenous serum bile acids in intrahepatic cholestasis of pregnancy (ICP). We sought to determine how it could influence the gut environment in ICP to alter enterohepatic signalling. The gut microbiota and bile acid content were determined in faeces from 35 pregnant women (14 with uncomplicated pregnancies and 21 with ICP, 17 receiving UDCA). Faecal bile salt hydrolase activity was measured using a precipitation assay. Serum fibroblast growth factor 19 (FGF19) and 7α-hydroxy-4-cholesten-3-one (C4) concentrations were measured following a standardised diet for 21 hours. Women with a high ratio of Bacteroidetes to Firmicutes were more likely to be treated with UDCA (Fisher’s exact test p = 0.0178) than those with a lower ratio. Bile salt hydrolase activity was reduced in women with low Bacteroidetes:Firmicutes. Women taking UDCA had higher faecal lithocholic acid (p < 0.0001), with more unconjugated bile acids than women with untreated ICP or uncomplicated pregnancy. UDCA-treatment increased serum FGF19, and reduced C4 (reflecting lower bile acid synthesis). During ICP, UDCA treatment can be associated with enrichment of the gut microbiota with Bacteroidetes. These demonstrate high bile salt hydrolase activity, which deconjugates bile acids enabling secondary modification to FXR agonists, enhancing enterohepatic feedback via FGF19.

A9 BACTERIAL BILE SALT HYDROLASE GENE ABUNDANCE IS ASSOCIATED WITH RORC GENE EXPRESSION IN INTESTINAL MUCOSA OF INFLAMMATORY DISEASE PATIENTS

Abstract Background The role of gut microbes involved in bile acid metabolism and their impact on mucosal immune regulation is beginning to be appreciated. For instance, changes in microbial bile salt hydrolase (BSH) activity which deconjugates bile acids in the gastrointestinal tract of gnotobiotic mice, significantly alters gene expression patterns of immune-related genes in ileum. Moreover, bile acid dysmetabolism may participate in the chronic inflammation loop of Inflammatory bowel disease (IBD). Aims We carried out an integrated mucosal microbiome-transcriptome analysis to elucidate associations between microbial bile-acid metabolizing function and host gene expression. Methods Crohn’s disease (CD), ulcerative colitis (UC) and IBD unclassified (IBDU) patients were recruited prior to scheduled colonoscopy performed as part of clinical care. Only patients with non-inflamed mucosa defined as a segmental simple endoscopic score 0–2 in CD and a segmental Mayo endoscopic score of 0 in UC/IBDU were included in this analysis to minimize the effect of inflammation on gene expression. Biopsy samples were obtained from terminal ileum, ascending colon and sigmoid colon, and microbial DNA and human RNA was extracted. V4 region of 16S rRNA gene was sequenced and the relative abundance of bile acid-metabolizing genes was inferred using PICRUSt. RNA-seq was used to sequence total human RNA and a supervised transcript reduction analysis focus upon 65 genes previously associated with bile acid metabolism and IBD was utilized. Associations between microbiome clusters of orthologous groups (COGs), transcriptome, diagnosis (CD vs UC/IBDU), and biopsy site were analyzed using linear mixed-effects model with lmer4 function in R. An adjusted-p value after false discovery rate correction &amp;lt; 0.05 was considered significant. Results A total of 126 samples from 86 subjects were analyzed corresponding to 35 CD and 51 UC/IBDU. Mean age for the total cohort was 34.7 ± 11 years and 35 (40.6%) were females. There was a significant negative correlation between relative abundance of bacterial bsh genes (COG3049) and human RORC gene (p &amp;lt; 0.03). This association was independent of type of diagnosis and biopsy site. There was no association among other analyzed bacterial COGs and host genes. Conclusions Using an integrative microbiome-host transcriptome approach, our data provide new evidence linking microbial bile acid deconjugation (bsh genes) and host gene expression in the mucosal-luminal interface in quiescent IBD-affected tissue. Nuclear receptor RORC is pivotal in the differentiation and function of innate lymphoid cells and T-helper 17 cells. Modulation of this pathway by bile acids or gut bacteria involved in their metabolism could shed light on the immune role of bile acids in IBD patients. Funding Agencies CAG, CIHRNational Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)

Prebiotics may alter bile salt hydrolase activity: Possible implications for cholesterol metabolism

Probiotics secrete bile salt hydrolase (BSH) which catalyses the deconjugation and excretion of bile salts in the GI tract altering cholesterol metabolism in the liver. Many probiotic preparations include prebiotics to promote probiotic growth but little is understood about how prebiotics affect BSH activity. In this study the ability of probiotic Lactobacilli species to deconjugate bile salts in the presence of various prebiotics was determined by measuring cholic acid release. The kinetic properties of BSH was assessed to determine the impact the prebiotics on bile salt deconjugation. When L. acidophilus NCTC 1723 was incubated with inulin (1 %) there was a significant (p < 0.01) increase in cholic acid release by 0.16 nmol/min. Lactulose and lactobionic acid at 1 % decreased cholic acid release to 0.2 nmol/min and 0.06 nmol/min respectively. In the presence of the pure BSH, inulin and lactulose (0–6 %) altered Km and Vmax of the enzyme with a Ki of 12 % and 10.5 % respectively. By contrast, lactobionic acid (2 %) increased BSH activity two-fold (p < 0.01).These results confirm that prebiotics are capable of altering BSH activity in vitro. Similar changes in vivo could potentially affect the claimed health benefits of synbiotics particularly where the desired outcome is lowering of serum cholesterol.

Development of a covalent inhibitor of gut bacterial bile salt hydrolases.

Bile salt hydrolase (BSH) enzymes are widely expressed by human gut bacteria and catalyze the gateway reaction leading to secondary bile acid formation. Bile acids regulate key metabolic and immune processes by binding to host receptors. There is an unmet need for a potent tool to inhibit BSHs across all gut bacteria in order to study the effects of bile acids on host physiology. Here, we report the development of a covalent pan-inhibitor of gut bacterial BSH. From a rationally designed candidate library, we identified a lead compound bearing an alpha-fluoromethyl ketone warhead that modifies BSH at the catalytic cysteine residue. Strikingly, this inhibitor abolished BSH activity in conventional mouse feces. Mice gavaged with a single dose of this compound displayed decreased BSH activity and decreased deconjugated bile acid levels in feces. Our studies demonstrate the potential of a covalent BSH inhibitor to modulate bile acid composition in vivo.

Study on intestinal survival and cholesterol metabolism of probiotics

Hypercholesterolemia drives the development of cardiovascular disease, Supplementation with probiotics that interfere with cholesterol metabolism provide a contribution to disease prevention. 54 strains with good hydrophobicity were measured bile salt hydrolase (BSH) activity and cholesterol removal ability. Evaluated the strains for probiotic potential with the intestinal colonization ability and the resistance to simulated digestion subsequently. 10 strains were finally selected for further characterization. As the potential functional strains, explored their effects on the expression of genes related to cholesterol metabolism and signaling pathways. 6 strains could regulate expression of Niemann–Pick C1-like 1 (NPC1L1) through farnesoid X receptor (FXR)/liver X receptor (LXR) pathway. Among of them, 4 strains could reduce the lipid deposition of ox-LDL-induced macrophages which had the potential abilities to improve atherosclerosis. Based on lipid-lowering abilities and common characteristics of probiotics, Lactobacillus vaginalis FN3 and Bifidobacterium animalis subsp. Lactis F1-7 could be taken as promising probiotic candidates for further in vivo studies and might have commercial value.

Cholesterol-Lowering Effects of Lactobacillus Species.

Probiotics are the living and non-pathogenic microbial supplements which, upon administration in adequate quantities, influence the host organism positively by improving gut health and enhancing intestinal mucosal integrity. They suppress potentially pathogenic microorganisms by competing with them for nutrients as well as space for gut adherence. Lactobacillus species are the most commonly used bacteria in the probiotic preparations and studies show that they have cholesterol-lowering effects on the hosts. Lipids are biological molecules that are insoluble in water and bile salts play a major role in their digestion as they are synthesized and conjugated to taurine or glycine in the liver. Bile salt hydrolase deconjugates taurine or glycine from bile salts. Cholesterol metabolism is influenced by the effect of Lactobacillus species on microbial populations as well as overall metabolic activity of human intestinal microflora. Deconjugation of bile salt, concentration of short-chain fatty acids and molar proportion of propionate constitute the major processes by which cholesterol lowering is brought about by Lactobacillus species. This review summarizes the cholesterol-lowering properties of this species. A significant number of Lactobacillus strains have been known to display substantial bile salt hydrolase activities and identifying those strains for use in therapeutic purposes can be a great advancement. Here, this identification is done using phylogenetic relationship for different identified potential probiotic Lactobacillus strains.

Abundance of Lactobacillus plantarum Strains with Beneficial Attributes in Blackberries (Rubus sp.), Fresh Figs (Ficus carica), and Prickly Pears (Opuntia ficus-indica) Grown and Harvested in Algeria.

This first study performed on traditional fruits consumed in North Africa reveals their richness in microorganisms with beneficial attributes like cholesterol lowering capabilities. Blackberries (Rubus sp.), fresh figs (Ficus carica), and prickly pears (Opuntia ficus-indica) are fruits largely and traditionally consumed in Kabylia, a beautiful northern Algerian region. Here, 85 lactic acid bacteria (LAB)-isolates were isolated and identified by MALDI-TOF mass spectrometry. The identified species belong to Lactobacillus and Leuconostoc genera. These 85 LAB-isolates were then assessed for their capabilities to grow under conditions mimicking the gastrointestinal tract, and the resulting data were statistically treated with principal component analysis (PCA). After which, only 26 LAB-isolates were selected and characterized for their genetic relatedness using random amplified polymorphic DNA (RAPD) method. Following the genetic relatedness assessment, only 10 LAB-strains, among which nine Lactobacillus plantarum and one Lactobacillus paracasei were studied for their pathoproperties and some probiotic features. Interestingly, all of these 10 LAB-strains were devoid of adverse effects, but capable to adhere to human epithelial colorectal adenocarcinoma Caco-2 cells. Of note, these 10 LAB-strains exhibited an important in vitro hypocholesteromia effect, in strain-dependent manner. Moreover, the Lactobacillus strains exhibited a high bile salt hydrolase (BSH) activity which was correlated with expression of bsh2, bsh3 and bsh4 genes.

In Vitro Characterization of Lactic Acid Bacteria from Indonesian Kefir Grains as Probiotics with Cholesterol-Lowering Effect.

Indonesian kefir grains are potential sources of lactic acid bacteria (LAB) that may act as probiotics with specific functional properties. In this study we explored the potential of the probiotic and cholesterol-lowering effect of LAB isolated from Indonesian kefir grains obtained from Bogor, Bandung, Jakarta, and Yogyakarta. The results revealed that 10 isolates showed considerable survivability at low pH and bile salt with total cell reduction of ~3 log colony-forming units per milliliter after exposure to pH 2.5 and 0.5% (w/v) bile salt for 1 and 3 h, respectively. All strains exhibited strong antimicrobial activities against pathogenic bacteria and were sensitive to a wide spectrum of antibiotics but exhibited weak bile salt hydrolase activity. Identification based on 16S RNA suggested that nine isolates were Lactobacillus kefiri and one was Lactobacillus rhamnosus. The ability of the isolates to reduce cholesterol from the media varied, ranging from 22.08% to 68.75% with the highest reduction shown by L. kefiri JK17. The ability to remove cholesterol from the media decreased greatly in resting and dead cells, ranging from 14.58% to 22.08% in resting cells and from 7.89% to 18.17% in dead cells. It can be concluded that Indonesian kefir grains contain LAB potentially acting as probiotics capable of reducing cholesterol. The cholesterol-lowering effect especially occurs when the cells are metabolically active.

Antibacterial activities of a polyphenolic-rich extract prepared from American cranberry (Vaccinium macrocarpon) fruit pomace against Listeria spp.

Cranberry (Vaccinium macrocarpon) fruits are known for their high polyphenolics content making them a rich source of antioxidants. These polyphenolics have been reported to promote human health and are gaining attention for their antimicrobial activities against foodborne pathogens. We investigated the antimicrobial activity of an ethanolic extract (#FC111-1) prepared from cranberry pomace against Listeria spp. Many polyphenolics were identified in this extract which could be responsible for growth-inhibitory effects against 12 Listeria strains including L. monocytogenes. The minimum inhibitory concentration (MIC) of #FC111-1 determined in cation adjusted Muller Hinton broth (CAMHB) was approximately 2 mg/mL for 11 (91.7%) of these strains. The inclusion of 2–8 mg/mL (1–4 × MIC) of #FC111-1 decreased (>3 log10) viable bacterial cells of all Listeria strains in CAMHB over a 24 h period, while dose-dependently reducing bacterial salt tolerance, bacterial bile-salt hydrolase activity, bacterial biofilm formation capacity, and increasing cell-membrane permeability. The #FC111-1 extract (0.4 and 0.8% concentrations) had no effect on L. monocytogenes survival in a cooked chicken-breast meat model, highlighting the influence of protein-rich matrices on antibacterial activity and the need to consider the role of food composition when using extracts or polyphenolics from cranberry fruits to improve food-safety.

Evaluation of lactic acid bacteria isolated from fermented mustards in lowering hypercholesterol by using bile salt hydrolase (BSH) activity and bile salt de-conjugation

This work evaluates lactic acid bacteria (LAB) obtained from fermented mustards for lowering cholesterol. The LAB strains’ ability to reduce cholesterol in vitro was determined using activity of bile salt hydrolase (BSH) and deconjugation of bile salt in vitro. The LAB strains were examined for their ability to resist acid and bile salt. Strains that can reduce cholesterol adhere to Caco-2 cells and they were identified. 9 LAB isolates had higher total BSH activity (1.07 to 1.92 U/mL) than the reference strains. BSH specific activity range from 1.33 to 3.13 U/mg. Due to different protein contents in the cell extracts, there was no good correlation between the exact BSH activity and total BSH activity by most of the isolates. All of the isolates deconjugated sodium glycocholate, freeing cholic acid, from 1.02 to 2.64 mM. The tested isolates deconjugated sodium glycocholate at different levels. All tested strains exhibited acid tolerance and bile tolerance; they can survive well at pH 3.0 for 3 h and bile tolerance for 24 h. Adhesion of the tested strains to the Caco-2 cell lines, strain B0007 and B0008 strongly adhere in comparison to the control strains and other isolated strains. These results demonstrated positive effect of isolates on BSH activity, deconjugation and thereby leading to the probiotic potential of lowering cholesterol. Key words: Lactic acid bacteria, acid- and bile-tolerant, bile salt hydrolase activity, deconjugation, adhesion activity.

Probiotic BSH Activity and Anti-Obesity Potential of Lactobacillus plantarum Strain TCI378 Isolated from Korean Kimchi.

Lactobacillus (Lab.) is a human probiotic beneficial for the prevention and improvement of disease, yet properties of different Lab. strains are diverse. To obtain a Lab. strain that possesses greater potential against gastrointestinal dysfunction, we isolated Lactobacillus plantarum TCI378 (TCI378) from naturally fermented Korean kimchi. TCI378 has shown potential as probiotic since it can survive at pH 3.0 and in the presence of 0.3% bile acid. The bile salt hydrolase activity of TCI378 was shown by formation of opaque granular white colonies on solid de Man Rogosa Sharpe (MRS) medium supplemented with taurodeoxycholic acid, and its cholesterol-lowering ability in MRS medium supplemented with cholesterol. The metabolites of TCI378 from liquid culture in MRS medium prevented emulsification of bile salts. Moreover, both the metabolites of TCI378 and the dead bacteria reduced oil droplet accumulation in 3T3-L1, as detected by Oil red O staining. The expressions of adipocyte-specific genes perilipin 1 and glucose transporter type 4 were suppressed by the metabolites of TCI378, indicating TCI378 may have anti-obesity effects in adipocytes. These in vitro data show the potential of the prophylactic applications of TCI378 and its metabolites for reducing fat and lowering cholesterol.

Evaluation of Bile Salt Hydrolase Activity, Bile Salt Deconjugation Ability, Cholesterol Assimilation Ability and Antioxidative Activity of Lactobacillus Cultures

Evaluation of Bile Salt Hydrolase Activity, Bile Salt Deconjugation Ability, Cholesterol Assimilation Ability and Antioxidative Activity of Lactobacillus Cultures