Optimization of ultrasonic-assisted extraction of bergenin from Rhizoma Bergeniae Scopulosae by response surface analysis

In order to optimize the conditions of ultrasonic-assisted extraction method of bergenin from Rhizoma Bergeniae Scopulosae,on the base of single-factor experiment,an equation for the ultrasonic wave extraction was built. The experiment showed that ultrasonic extraction power,extraction time,ethanol concentration and extraction temperature had different effects on the extraction yield of bergenin. The result indicated that within tested level ranges,the importance of four process parameters affecting extraction yield of bergenin order were ultrasonic extraction temperature,ultrasonic power,ethanol concentration and ultrasonic extraction time. The optimum extraction conditions of bergenin were obtained as follows:the extraction temperature 59 ℃,extraction ultrasonic power 270 W,ethanol concentration 75%,extraction time of 40 minutes,the solid-liguid ratio was1∶30,the extracting times was 3. The yield of bergenin could achieve 6.429%,exhibiting a good agreement with the predicted value.