Biotransformation Of Panoxatriol Type Ginsenosides

This paper based on the panoxatriol type ginsenoside Re which was enzymatic conversed by the enzyme from Aspergillus sp.39.lt also can enzymatic converse Re,Rg1to Rg2,Rh1by Microbacterium sp.GS514.The simple saponin Rg1,Rg2were prepared and (R)-Rg2,(S)-Rg2was been splited.For one aspact,this paper was deeply studied about the enzymatic character for transform ginsenoside Rg1,and the most activity Aspergillus sp.39was chose from six kinds of fungus.The enzyme of Aspergillus sp.39was abstracted by DEAE-Cellulose exchange chromatography and56kDa molecular weight was determined by SDS-Polyacrylamide gel.The optimal condition for enzyme reaction was been selected, and the optimal concentration of substrate for enzyme reaction is1.0%,the optimal temperature is30℃,the optimal substrate pH is6.0.For another aspact, ginsenoside Rg2was prepared by both weak acid hydrolysis and enzymatic. Rg2,Rh1were prepared by50g Re which was reacted with enzyme from Microbacterium sp.GS514for24h in40℃.The production were crude separated by AB-8macroporous adsorptive.75%alcohol eluant was been collected and then silica gel was used to separate ginsenoside Rg2.The mobile phaseis CHCl3:Methanol=8.5:1.5,and5.07g Rg2was been collected which yield is13.7%.The ginsenoside in this experiment was separated from saponin of ginseng leaf which was provided by our lab.The pure monomer saponin was epurate by recrystallization and been detected by high performance liquid chromatogram.9.74g Re crystal from20g saponin Re, and its purity was99%.According to different solubility of (R)-Rg2and (S)-Rg2,2g Rg2were splited by recrystaing.0.62g (S)-Rg2which has little solubility was separated from the saturated solution fistly and its purity was95.3%.