Conversion of Gihsenoside Rb₁ by Ginseng Soil Bacterium Cellulosimicrobium sp. Gsoil 235 According to Various Culture Broths

Ginseng saponins (a secondary metabolite, termed ginsenosides) are the principal bioactive ingredients of ginseng, and modification of the sugar chains may markedly change the its biological activity. One of soil bacteria having β-glucosidase (to transform ginse- noside Rb₁) activity was isolated from soil of a ginseng field in Daejeon. 16S rRNA gene sequence analysis revealed that the isolate belonged to the genus Cellulosimicrobium, with highest sequence similarity (99.7%) to Cellulosimicrobium funkei ATCC BAA-886^T. The strain, Gsoil 235, could transform ginsenoside Rb ₁ into Rd, Rg₃ and 3 of un-known ginsenosides by the analyses of TLC, HPLC. By investigating its deglycosylation progress, the optimal broth for β-glucosidase was nutrient broth (In 48 hours, almost ginsenoside Rb₁ could be transformed into minor ginsenosides). On the contrary, the optimal broth for growth was determined as trypic soy broth (TSB).