The purpose of this study was to isolate probiotic
lactic acid bacteria (LAB) that produce bile salt hydrolase
(BSH), and to evaluate its effects on serum cholesterol level.
One-hundred-twenty bacterial colonies were initially isolated
from human feces, and five strains were selected after screening
based on their resistance to acids, tolerance against bile salts,
and inhibitory activity on Escherichia coli. The Lactobacillus
plantarum strain with the highest level of BSH activity was
identified using 16S rRNA sequences, and was named L.
plantarum CK 102. L. plantarum CK 102 at a level of 1.36×
108 cfu/ml survived in pH 2 buffer for 6 h and exhibited
excellent tolerance for bile salt. Coculturing the strain with E.
coli in MRS broth resulted in strong inhibition against growth
of E. coli at 18 h. Furthermore, the potential effect of CK 102
on serum cholesterol level was evaluated in rats. Thirty-two
rats [Sprague-Dawley (SD) male, 129±1 g, 5 weeks old] were
divided into four groups of eight each. For six weeks, Group 1
was fed a normal diet (negative control); Group 2 was fed a
cholesterol-enriched diet (positive control); Group 3 was fed
a cholesterol-enriched diet plus L. plantarum CK 102 at 1.0×
107 cfu/ml; and Group 4 was fed a cholesterol-enriched diet
plus L. plantarum CK 102 at 5.0×107 cfu/ml. Blood samples were
collected, serum lipids were analyzed, and weights of the organs
were measured. Total blood cholesterol level, triglyceride, LDLcholesterol, and free-cholesterol values were lower in rats that were
fed L. plantarum CK 102 than in those not fed L. plantarum
CK 102. This cholesterol lowering effect implies that L. plantarum
CK 102 could be utilized as an additive for health-assistance
foods. In conclusion, these results suggest that the L. plantarum
CK 102 isolated could be used commercially as a probiotic.