To understand the role of intestinal microflora in expressing the pharmacological effect of ginsenoside Rb1, the metabolic activity of ginsenoside Rb1 by 148 fecal specimens was measured and its metabolizing β-glucosidase was cloned. The average activities for p-nitrophenyl-β-D-glucopyranoside and ginsenoside Rb1 were 0.097±0.059 μmol/min/mg and 0.311±0.118 pmol/min/mg, respectively. These enzyme activities were not different between male and female, or between ages. A gene encoding β-D-glucosidase (BglX) was cloned from Bifidobacterium longum H-1, which transformed ginsenoside Rb1 to compound K. The probe for cloning was synthesized from the genes encoding a β-D-glucosidase of previously reported B. longum DJO10A. The sequences of the cloned gene revealed 2364 bp open reading frame (ORF) encoding a protein containing 787 amino acids (molecular weight of 95 kDa). The gene exhibited 99

作者：Il-Hoon, Jung；Jeong Hoon, Lee；Yang-Jin, Hyun；Dong-Hyun, Kim

来源：Biological & pharmaceutical bulletin 2012 年 35卷 4期