Effects of Different Extraction Methods on Extraction Rate of Polysaccharide from Sonchus oleraceus L.

[Objective]The aim was to screen method for extracting polysaccharide from Sonchus oleraceus L.[Method] Ultrasonic wave,microwave irradiation and Ultrasonic-microwave synergistic extraction method were designed to compare with water bath method.With extraction rate of crude polysaccharide as an indicator,the methods were evaluated.[Result] Four extraction methods all have significant influences on extraction rate of S.oleraceus polysaccharide(P0.05),the extraction rate of ultrasonic-microwave synergistic method was highest as 23.16%,followed by microwave,water bath and ultrasonic wave,with extraction rate as 22.33%,20.98% and 19.54%.[Conclusion] Ultrasonic-microwave synergistic extraction method was best,accurately weigh 5.0 g S.oleraceus dry powder,add 100 ml distilled water,after mixing,put on ultrasound-microwave instrument to extract.Ultrasonic power was 50 W,frequency was 50 kHz;microwave frequency was 2 450 MHz.Under 80 ℃,extracting for 30 min,and through filtering,residue repeat extraction for 1 time,collecting filtrate,with 200 ml as constant volume,the polysaccharide content was determined.With glucose as standards,choosing anthrone-sulphuric acid colorimetry,the linear range of glucose concentration was 10-100 mg/ml,colorimetric wavelength was 620 nm,the average recovery rate was 100.29%,RSD value was 0.22%(n=5).