Biotransformation of ginsenoside Rb1 to Gyp-XVII and minor ginsenoside Rg3 by endophytic bacterium Flavobacterium sp. GE 32 isolated from Panax ginseng.

The rare ginsenoside Rg3 is attracting more attention because of its good physiological activity and urgently required. There are many pathways to obtain ginsenoside Rg3, including chemical and biological methods. Among these, the conversion of PPD-type ginsenosides by microbial hydrolysis is a trend due to its high efficiency and mild conditions. For effectively extracting from the other panaxadiol saponins, the conversion process for ginsenoside Rg3 was investigated using β-glycosidase-producing endophytic fungus in Panax ginseng in this study. The metabolic pathways: ginsenoside Rb1→Gyp-XVII and ginsenoside Rb1→ginsenoside Rd→ginsenoside Rg3. Phylogenetic analysis of 16S rDNA gene sequence, the strain named GE 32 was identified as Flavobacterium sp.. These results suggest that the process of rare ginsenoside Rg3 production by endophytic bacteria GE 32 is efficient for the industrial production and application. This article is protected by copyright. All rights reserved.