title: Bile enhances cell surface hydrophobicity and biofilm formation of bifidobacteria.
abstract: Twenty-four human bifidobacterial strains were analysed for cell surface hydrophobicity (CSH) using a salt aggregation test (SAT) and a Congo red binding (CRB) assay. Three strains were selected for a systematic study on the CSH and biofilm formation: Bifidobacterium breve 46, Bifidobacterium animalis ssp. lactis 8:8 and a reference strain B. animalis ssp. lactis JCM 10602. CRB of the B. breve 46 and B. animalis ssp. lactis JCM 10602 was significantly enhanced (P < 0.05) when grown in deMan-Rogosa-Sharpe cysteine (MRSC) broth supplemented with taurocholic acid (TA) or native porcine bile (PB). An enhanced CSH of the strains grown with PB and gastric mucin correlated with an increased mucin binding and an enhanced biofilm formation in prebiotic oligosaccharide-supplemented cultures. The three strains showed late bile-induced biofilm (72 h) under an anaerobic growth condition, and both B. animalis ssp. lactis strains showed a late bile-induced biofilm formation under aerobic conditions shown by crystal violet staining. These two strains were thus considered to be oxygen tolerant and more robust. Furthermore, enhanced biofilm formation of these robust bifidobacterial strains in the presence of prebiotics may allow for strong colonisation in the gastrointestinal tract when administered to in vivo models as a "synbiotic supplement".
authors: Labmedicine Skåne, Department of Clinical Microbiology, Sölvegatan 23, 223 62, Lund, Sweden.
authors: Padma
authors: P
authors: Ambalam
authors: Kanthi Kiran
authors: KK
authors: Kondepudi
authors: Ingrid
authors: I
authors: Nilsson
authors: Torkel
authors: T
authors: Wadström
authors: Asa
authors: A
authors: Ljungh
mesh_terms: D001644:Bifidobacterium / Q000187:drug effects / Q000254:growth & development* / Q000378:metabolism*; D001646:Bile; D018441:Biofilms / Q000187:drug effects / Q000254:growth & development*; D057927:Hydrophobic and Hydrophilic Interactions; D013656:Taurocholic Acid / Q000494:pharmacology
chemical_list: D013656:Taurocholic Acid