菟丝子提取物清除自由基作用的研究

目的 研究菟丝子提取物的体外抗氧化活性.方法 采用热水提取、酶-Sevage法除蛋白、不同比例乙醇分级沉淀等方法获得菟丝子多糖提取物；经95％乙醇回流提取,2乙酸乙酯、正丁醇萃取,得到乙酸乙酯和正丁醇提取物.利用1,1-二苯基-2-苦苯肼自由基(DPPH·)和超氧阴离子自由基(O2-·)分别测定了各组分的抗氧化活性.结果 菟丝子提取物均具有一定的抗氧化活性,且呈显著的量效关系.菟丝子乙酸乙酯、正丁醇提取物清除自由基的能力大于氧化型谷胱甘肽,小于还原型谷胱甘肽；菟丝子多糖清除自由基的能力均小于氧化型谷胱甘肽,其中90％醇沉多糖清除自由基的能力较强.结论 菟丝子乙酸乙酯、正丁醇提取物以及90％醇沉多糖是天然抗氧化剂的良好来源,可以进一步分离纯化.

Free radical scavenging of the extract from Cuscuta chinensis Lam

Objective To investigate the in vitro antioxidant activity of the extract from Cuscuta chinensis Lam.Methods The polysaccharides were obtained by distilling with hot water,removing proteins with enzyme-Sevage method,further precipitating with different ethanol ratios.The extracts of ethyl acetate and n-butyl alcohol were obtained by distilling with 95% ethanol and extracting with ethyl acetate and n-butyl alcohol.Meanwhile their antioxidant activity was measured by DPPH· and(O2-) methods.Results The extract from Cuscuta chinensis Lam had obvious antioxidant activity and showed significant dose-effect relationship.The antioxidant activity of ethyl acetate and n-butyl alcohol extract was better than that of GSSG,but worse than that of GSH.The antioxidant activity of polysaccharide was worse than GSSG.The polysaccharide precipitated by 90% ethanol had stronger antioxidant activity.Conclusion The polysaccharide precipitated by 90% ethanol and the ethyl acetate and n-butyl alcohol extract are good natural antioxidants,which is worth further separation and purification.