title: Ability of Bifidobacterium strains with acquired resistance to bile to adhere to human intestinal mucus.
abstract: The hydrophobicity and capacity to adhere to human intestinal mucus of Bifidobacterium strains with acquired resistance to bile were assessed and compared with those of their more sensitive original strains. The resistant variants used were previously obtained [Int. J. Food Microbiol. 82 (2003) 191; Int. J. Food Microbiol. 94 (2004) 79] by progressive adaptation of originally more sensitive strains to gradually increasing concentrations of bile. In five out of the seven groups of original and bile-resistant variants tested the resistant strains showed higher adhesion levels to human mucus (range between 1.4- and 4-fold) than their corresponding original strains. However, in the presence of physiologic concentrations of bile (0.3%, w/v) the adhesion level of all Bifidobacterium strains dropped between 7% and 74%, depending on the strain. In spite of this, the adhesion capability of three bile-resistant variants remained higher than that of their originals. Hydrophobicity evidenced considerable variability; in four out of the seven bile-resistant strains it was higher than in the original strains, although no direct correlation between adhesion and hydrophobicity could be established. It was concluded that the acquisition of bile resistance by our Bifidobacterium strains promoted changes in hydrophobicity and in the adhesion of these microorganisms to human intestinal mucus.
authors.affiliation: Department of Biochemistry and Food Chemistry, University of Turku, Vatselankatu 2, FIN-20014 Turku, Finland. miguel.gueimonde@utu.fi
authors.forename: Miguel
authors.initials: M
authors.lastname: Gueimonde
authors.forename: Luis
authors.initials: L
authors.lastname: Noriega
authors.forename: Abelardo
authors.initials: A
authors.lastname: Margolles
authors.forename: Clara G
authors.initials: CG
authors.lastname: de los Reyes-Gavilan
authors.forename: Seppo
authors.initials: S
authors.lastname: Salminen
mesh_terms: D000222:Adaptation, Physiological; D001422:Bacterial Adhesion / Q000502:physiology*; D001644:Bifidobacterium / Q000254:growth & development / Q000502:physiology*; D001647:Bile Acids and Salts / Q000378:metabolism*; D005516:Food Microbiology; D006801:Humans; D066298:In Vitro Techniques; D007413:Intestinal Mucosa / Q000382:microbiology*; D008826:Microbial Sensitivity Tests; D019936:Probiotics
chemical_list: D001647:Bile Acids and Salts