Extraction,Separation,Purification And Antioxidant Activity Of Dioscorea Opposita Thunb.cv.Tiegun Polysaccharide

In the issue,polysaccharide compounds were obtained from the traditional Chinese medicines of Chinese yam--Dioscorea opposita Thunb.cv.Tiegun,polysaccharide compounds would been provided reliable samples for functional activity study.Chinese yam polysaccharide was obtained through the ultrasonic-microwave synergistic extraction method,and macroporous resin was used to purify polysaccharide compounds from the crude extract,finally,single polysaccharide compounds were separated by DEAE-52 cellulose column and Sephadex G-100 chromatography method,and the in vitro antioxidant activities of the isolated Chinese yam polysaccharides were evaluated.The results are as follows:1.The determination of polysaccharide extracted Chinese yam was refered the total sugar determination method-phenol sulfuric acid method.The polysaccharide was extracted from Chinese yam using ultrasonic microwave synergistic extraction method,and the single factor experiment and response surface were used to optimize three parameter of ultrasonic-microwave synergistic extraction method(microwave power,microwave time,solid-liquid ratio),and the optimum parameters: microwave power 380 W,microwave time 360 s,ratio of solid to liquid 1:10 g/mL,Chinese yam polysaccharide yield was 1.39%,the purity was 22.13%.2.The effects macroporous adsorption resin were studied,and AB-8 resin was the best choice to purified polysaccharide.The static and dynamic adsorption experiments were executed,on the sample loading,sample concentration was 1.02 g/L,flow speed was 500 mL/h,sample volume was 4000 mL.On the elution test,the elution flow speed was 750 mL/h,the elution agent volume was 1000 mL,The resolution rate would achieve 95.62%.The purities of Chinese yam polysaccharide increased from 22.13% to 82.57%,and the yield was 91.74%.3.After obtaining crude sample of Chinese yam polysaccharide,DEAE-52 cellulose column was used for preliminary separation,and two polysaccharide constitutes were separated succesfully.Then,Sephadex G-100 column chromatography was used to separate them.The first component was separated to two Chinese yam polysaccharide fractions,respectively CYP1 and CYP2;the second component was separated to one fraction,CYP3.After calculation,the results showed that the yield of CYP1 is 0.34%,the purity is 93.11%;the yield of CYP2 is 0.41%,the purity is 91.23%;the yield of CYP3 is 0.31%,and the purity is 92.75%.4.For investigation of antioxidant activities of three Chinese yam polysaccharide fractions,ABTS radical scavenging,DPPH free radical scavenging,total reducing capacity were used to evaluate the antioxidant activities of the purified Chinese yam polysaccharide fractions in vitro.The antioxidant activities of the three Chinese yam polysaccharide fractions were excellenter than Ve,and the antioxidant caparity of the Chinese yam polysaccharide CYP1 component were best in the evaluation of three experiments,and CYP1 component would been an effective component of functional food in the future.