Antioxidant Activity Of Polysaccharide From Chinese Yam And Its Inhibitory Effect On HT-29 Cell Proliferation

Yam is a crude polysaccharide rich in many edible plants, such as adjusting immunity, anti-aging, anti-tumor, hypoglycemic and other pharmacological effects, wide application prospect. In this paper, the ultrasonic assisted extraction technology of polysaccharides from yam was studied, and its antioxidant activity and inhibitory effect on the growth of HT-29 cells in colon cancer cells were analyzed. The main results are as follows:(1) Yam powder as raw material, through the single factor and response surface methodology to optimize yam polysaccharide ultrasonic assisted extraction process, the results showed that:solid-liquid ratio was 1:26 (g:mL), ultrasonic power 600W, ultrasonic time 93min, ultrasonic temperature is 71℃, the resulting yam polysaccharide was 8.27%.(2) Compare enzymatic protein removal rate Sevage law and TCA law and polysaccharide retention rate, the results showed that:the best enzyme, polysaccharides retention and protein removal rate was 90.39% and 72.46%, respectively. Yam polysaccharide by DEAE-Cellulose 52 column chromatography to obtain yam neutral and acidic polysaccharides S1 and S2, using Sephadex G-100 chromatography by UV scanning the sample does not contain large proteins, polypeptides and nucleic acids, identified as pure product.(3) Yam polysaccharide in vitro antioxidant activity detection results show that the yam polysaccharide on hydroxyl radical and superoxide anion scavenging effect to some extent, within the scope of this study selected concentration increased. Concentration of 5 mg/mL, yam neutral polysaccharide S1 to clear on superoxide anion in addition to the rate of 67.81%, yam acidic polysaccharides S2 on superoxide anion free radical clearance rate of 71.37%; Yam neutral polysaccharide S1 to hydroxyl free radical inhibition rate was 83.89%, and the Chinese yam, acidic polysaccharides S2 on hydroxyl free radical inhibition rate of 89.20%.(4)Determined by MTT cell proliferation test research of yam polysaccharide on colon cancer cell HT-29 cell growth inhibition, the results show that in the certain concentration range, yam polysaccharide can inhibit the HT-29 cell proliferation, set in the concentration range of inhibition of cell proliferation in time and dose dependent effect. When Chinese yam polysaccharide concentrations for 1000 (including g/mL, HT-29 cell culture respectively after 24h,48h,72h, the inhibition rate of 21.53%,26.41% and 29.12% respectively.