Effects of Extraction Methods on Contents and Compositions of Ginsenosides from Cultivated Jilin Ginseng Extracts

The effect of different extraction methods,supercritical fluid extraction(SFE),ultrasound-assisted extraction and heat reflux extraction,on the extraction efficiencies and compositions of 6 major ginsenosides including Rg1,Re,Rb1,Rc,Rb2 and Rd from cultivated Jilin ginseng was investigated.The ginsenosides were determined by HPLC.The total yield of ginsenosides extracted by SFE,ultrasound-assisted extraction and heat reflux extraction was respectively 0.8557%,2.2938% and 2.4804%,and the yields of Rg1,Re,Rb1,Rc,Rb2 and Rd were 0.1287%,0.1169%,0.2830%,0.1090%,0.1061% and 0.1120% when using SFE,0.3892%,0.3414%,0.8088%,0.2932%,0.3180% and 0.1432% when using ultrasoundassisted extraction,and 0.3914%,0.3396%,0.8898%,0.3300%,0.3620% and 0.1676% when using heat reflux extraction,respectively.In the HPLC chromatogram of the heat reflux extract,several peaks disappeared,suggesting the degradation of malonyl ginsenoside.In addition to six common gensinosides,a small amount of unknown secondary ginsenosides were also detected in the extracts from three methods.Based on this,we deduced that neutral ginsenosides were degraded to different extents under SFE,ultrasound assisted-extraction and heat reflux extraction.The above results showed that there was a significant difference in the extract yields and compositions of ginsenosides when different extraction methods were employed.In respect to SFE,the extraction yields of ginsenosides were significantly lower than those observed when using ultrasound-assisted extraction and heat reflux extraction.However,SFE had excellent advantages such as simpler separation process,the absence of solvent contamination and better thermo-sensitive substance protection and higher re-utilization value of the remaining residue.