Probiotic characterization and in vitro cholesterol lowering effects of lactic acid bacteria isolated from healthy Thai infants

Abstract

Hypercholesterolemia is one of the major health problems affecting people worldwide. Some probiotic lactic acid bacteria possess cholesterol lowering ability. One-hundred lactic acid bacteria isolated from the feces of healthy Thai infants were screened for bile salt hydrolase activity and cholesterol assimilation ability. Seven isolates expressed strong bile salt hydrolase activity and 7 isolates exhibited cholesterol assimilation properties. In total, 11 probiotic candidates were characterized for their general probiotic properties including acid and bile tolerance, adherence to Caco-2 cells and genotypic identification using 16S rRNA gene sequencing. Eight isolates were identified as Enterococcus faecalis and others were E. faecium, E. durans, and Lactococcus garvieae. All selected isolates survived after incubation at pH 3 and 4, and in 0.3% and 0.8% bile. The strain E. faecium MSMC 25-2 exhibited the highest level of adhesion to Caco-2 cells at 8.8% compared to L. rhamnosus GG.

Keywords

• bile salt hydrolase
• probiotics
• lactic acid bacteria
• cholesterol
• infant feces