Separation and Cytotoxicity of Enzymatic Transformed Prosaikogenins from Bupleurum falcatum.

Abstract

Saikosaponins, bioactive compounds derived from Bupleurum falcatum roots, have limited applications due to their low bioavailability and the absence of efficient large-scale separation methods. To address this, an enzymatic transformation in vitro with cellulase was employed to remove glucose at the C-3 position, producing lipophilic prosaikogenins. These metabolites were separated using countercurrent chromatography (CCC) and preparative HPLC. The optimal CCC solvent system was determined to be dichloromethane/methanol/water (4 : 3 : 2, v/v/v). Prosaikogenin F and prosaikogenin G (PSG G) were isolated from the deglycosylated fraction, and the effect of rotation speed on compound retention was examined. Further enzymatic biotransformation using α-L-rhamnosidase and cellulase resulted in the isolation of prosaikogenins E₁ and E₃. The efficient separation of these four prosaikogenins was achieved through a combination of enzymatic transformation and CCC. Of these, PSG G demonstrated the strongest anticancer activity against the cancer cell lines MDA-MB-468, HepG2, and HCT116, while exhibiting lower toxicity in normal cells, supporting its potential as an effective anticancer agent. This study presents a highly efficient enzymatic transformation and separation strategy that can aid in the pharmaceutical development of saikosaponin derivatives.