Human intestinal bacteria hydrolyze ginsenoside, triterpenoid glycoside of Panax ginseng C. A. MEYER (Araliaceae) to the active metabolites: however, metabolite-producing potentials of intestinal bacteria are shown to differ among individuals. In the present study, we evaluated the probiotic effects of L. paracasei A221, a bacterium capable of producing metabolites from ginsenoside, on 136 human volunteers. Four-week-ingestion of L. paracasei A221 improved fecal smell (p<0.001,n=119) and constipation (p<0.001,n=55). In addition,L. paracasei A221 also improved the symptoms of pruritus (67.7%,p<0.001,n=31), dermopathy (52.3%,p<0.001,n=65), pollinosis (49.0%,p<0.001,n=51), dry skin (46.3%,p<0.001,n=41), and sleep disruption (28.8%,p<0.02,n=52). Besides results from T-RFLP analysis confirmed the recovery of L. paracasei A221 from the feces of volunteers. These data provide evidence that L. paracasei A221 is one probiotic strain. As for metabolite-producing potentials, the treatment of volunteers with no or less metabolite-producing potentials with L. paracasei A221 was highly effective in augmenting metabolite-producing potentials. Moreover, the average score of ginseng efficacy was actually improved with an efficiency of 63.2%(p<0.0001,n=57)by 4-week-ingestion of L. paracasei A221. These results permit us to speculate that L. paracasei A221 is available for standardizing metabolite-producing potentials of intestinal bacteria.
