Deconjugation of bile acids by lactobacilli in the mouse small bowel.

Conjugated and unconjugated bile acid concentrations in the small bowel contents and portal serum samples collected from mice with and without lactobacilli (RLFL and RLF, respectively) as gastrointestinal inhabitants were measured. The major portion of bile acids in the small bowel contents of RLFL mice was unconjugated (67.9%) in contrast to that of RFL animals in which a smaller portion of bile acids was unconjugated (23.5%). This study demonstrated that bile salt hydrolase produced by lactobacilli is active under the conditions prevailing in the proximal small bowels of mice.