Preparation Of Protopanaxadiol Type Ginsenosides Rg₃

Ginsenoside Rg3is one of important physiological activity ingredients in ginseng, plays an important role in anti-tumor, belongs to protopanaxadiol type saponin. In this paper, ginsenoside Rg3(3-O-β-D-glucopiranosyl-(1â†'2)-β-D-glucopiranosyl protopanaxadiol) was seperated from protopanaxadiol type (PPD) which extracted from ginseng root, further more20(S)-Rg3and20(R)-Rg3were separated from the mixture ginsenoside Rg3.First of all,36.95g PPD extracted from1.0kg ginseng root by solvents was separated by silica gel column chromatography, obtaining Rb123.66g, Rc4.12g and Rd4.72g which were used to be substrate in preparation of ginsenoside Rg3reaction.The enzyme isolated from bacterium Arthrobacter sp.3was used to hydrolyze PPD to ginsenoside Rg3. The optimal fermentation inducer was0.1mg/ml PPD; and the optimal temperature was40℃, the optimal time was24h, the optimal substrate concentration was0.1mg/ml. The yield of ginsenoside Rg3hydrolyzed by the enzyme from Arthrobacter sp.3was21%under the optimal conditions detected by HPLC.19.0g pure ginsenoside Rg3was obtained with separat and purify mothod from29.5g mixture ginsenoside Rg3and Rgs by silica gel column chromatography.Crystallization was used to separate the20(S)-Rg3and20(R)-Rg3. The purity of20(S)-Rg3crystallized for the second time is97.21%, while the purity of20(R)-Rg3crystallized for the second time is78.35%.