Biotransformation of Ginsenoside Rc into C-Mc 1 by the Bacterium Sphingopyxis sp. BG97

The principal biologically active compounds of Panax ginseng C. A. Meyer are triterpenoid glycosides, ginsenosides [1], which exhibit immunostimulating, anti-inflammatory, anticarcinogenic, antitumor, antidiabetic, hepatoprotective, neuromodulating, and other properties [2]. Greater than 50 different ginsenosides have been isolated from P. ginseng. Six of these (Rb1, Rb2, Rc, Rd, Re, and Rg1) make up >80% of total saponins and have protopanaxadiol or protopanaxatriol as the aglycon [1]. Furthermore, it is well known that minor glycosides of P. ginseng in several instances have broader spectra of biological activity or are more active than them [2]. This stimulates great interest in producing the minor ginsenosides, including biotransformation of the principal ginsenosides using various microorganisms [3, 4]. We reported earlier the transformation of ginsenoside Rb1 into the minor glycoside F-2 and compound K [5] and glycoside Rd into minor ginsenoside (20S)-Rg3 [6] using bacteria isolated from soil samples taken from a ginseng field. Among these, strains belonging to the genus Sphingopyxis were identified [7]. Herein we communicate data on the transformation of principal ginsenoside Rc (1) into minor compound C-Mc1 (2) by the bacterium Sphingopyxis sp. BG97.