Enzymatic transformation of ginseng leaf saponin by recombinant β-glucosidase (bgp1) and its efficacy in an adipocyte cell line.

The major ginseng leaf saponins are transformed into the more pharmacologically active minor ginsenosides by recombinant β-glucosidase enzyme bgp1. Ginseng leaves contain six major ginsenosides: Rg1, Re, Rb1, Rb2, Rc, and Rd. Among these Rg1, Re and Rd are the most abundant. Within 3 H of incubation, all dominant major ginsenosides found in ginseng leaf had decomposed and been converted into the more active minor ginsenosides (i.e., 100% of Rg1, Re, and Rd were decomposed and converted into Rh1, Rg2, and Rg3, respectively). The recombinant β-glucosidase enzyme (bgp1) hydrolyzed all glucose moieties attached to the C-20 position of the ginsenosides Rg1, Re, Rb1, Rd, and F1. The transformed product contains pharmacologically active minor ginsenosides Rh1, Rg2, Rg3, F1, and protopanaxatriol. This transformed product was used to investigate the effects on the 3T3-L1 adipocyte cell line. The cytotoxicity assay did not show any toxicity, even when used at a concentration of 100 μg/mL. Adipogenesis was shown to decrease in response to bioconverted leaf saponin in a dose-dependent manner.