title: Effect of clindamycin given alone or with Lactobacillus delbrueckii and Streptococcus thermophilus on 7alpha-dehydroxylation of bile acids in rats.
abstract: OBJECTIVES: To evaluate the influence of clindamycin, given alone or with Lactobacillus delbrueckii and Streptococcus thermophilus to conventional rats, on 7alpha-dehydroxylation of cholic acid to deoxycholic acid. METHODS: The presence of deoxycholic acid was determined by gas-liquid chromatography. The fecal concentration of clindamycin was determined on PDM antibiotic sensitivity medium. Colony-forming units of L. delbrueckii and S. thermophilus were counted on lactic acid bacteria agar, and their ability to deconjugate was determined by thin-layer chromatography. RESULTS: Clindamycin significantly reduced the formation of deoxycholic acid, while the administration of lactobacilli-streptococci at the same time significantly reduced the effect of the antibiotic (p<0.05). CONCLUSIONS: Clindamycin reduced the formation of deoxycholic acid in rats and this effect was diminished by concomitant administration of L. delbrueckii and S. thermophilus. As the given microbes could not 7alpha-dehydroxylate, it seems reasonable to assume that they stimulate microbial species already present in the intestine.
authors.affiliation: Laboratory of Medical Microbial Ecology, Department of Cell and Molecular Biology, Karolinska Institute, Stockholm, Sweden.
authors.forename: Aina
authors.initials: A
authors.lastname: Gustafsson
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Norin
authors.forename: Tore
authors.initials: T
authors.lastname: Midtvedt