Enzymatic biotransformation of ginsenoside Rb1 by recombinant β-glucosidase of bacterial isolates from Indonesia

β-Glucosidase (EC. 3.2.1.21) is of industrial interest due to its critical role in the utilization of cellulosic biomass to produce high-value chemical compounds and biofuels. Moreover, β-glucosidases can be utilized in the biotransformation of high value plant active materials such as ginsenosides. In this report, we confirmed the biotransformation activity of ginsenosides by β-glucosidases from Bacillus sp. 3 KP and Serratia marcescens LII61 strains isolated from Indonesia. β-Glucosidases from both bacterial strains were cloned and overexpressed in Escherichia coli BL21 (DE3). Crude cell extract of E. coli BL21 (DE3) overexpressing the β-glucosidase were used for the biotransformation of ginsenosides Rb1. Results showed that the Rb1 was biotransformed to the more pharmacologically active rare ginsenosides, gypenoside XVII and F2. This work is the first effort to use β-glucosidases from Indonesian bacterial strains for ginsenosides biotransformation and is expected to encourage further exploration of β-glucosidase-producing bacterial strains from Indonesia.