Soil Bacterial Hydrolysis leading to Genuine Aglycone. V. On Ginsenosides-Rb1, Rb2, and Rc of the Ginseng Root Saponins

Through the application of the soil bacterial hydrolysis method on a mixture of ginsenosides Rb1, Rb2, and Rc, an additional evidence on the genuineness of 20 (S)-protopanaxadiol (I) has been provided. In addition, a prosapogenol (termed as compound K) has been isolated as a major hydrolysate and the structure has been assigned as 20-O-β-D-glucopyranosyl-20 (S)-protopanaxadiol (VI).