Abstract: In this study,total ginsenoside was extracted from the adventitious roots of Panax ginseng C.A.Meyer by ethanol extraction method.The extraction process was optimized by response surface methodology (RSM).Using the total yields of Rb1, Rb2,Rc,Rd,Re and Rg1 as responses,main factors,including extraction temperature, ethanol concentration and liquid-to-solid ratio,were investigated.Based on the results of single factor test,response surface methodology with 3 factors and 3 levels was applied according to Box-Behnken experimental design principle.The relationships between the yield of total ginsenoside and factors were investigated by response surface experiments,and then the regression equations were established.The optimal results were simulated using the regression models based on the value of response surface.The optimized extraction process of total ginsenoside were determined as follows:extraction temperature of 70 ℃,ethanol concentration of 73.50% and solid-liquid ratio of 1:34.50 (g/mL),under which the yield of total ginsenoside was up to 1.86±0.01%.

Key words: Panax ginseng C.A.Meyer, ginsenoside, extraction technology, response surface methodology