甘薯多糖抗氧化作用研究

目的]探讨甘薯多糖清除活性氧自由基的机制。方法]以已分离提纯的甘薯多糖为试验材料,利用分别产生氧自由基(O2-·)和羟自由基(·OH)的化学模型体系,研究甘薯多糖清除羟自由基能力及其对邻苯三酚自氧化的抑制作用和甘薯多糖对荷瘤小鼠SOD活性和丙二醛(MDA)含量的影响。结果]在体外,甘薯多糖对(O2-·)和·OH均有清除作用,且与甘薯多糖浓度成正相关性。在活体内,甘薯多糖的抗氧化与抗肿瘤作用表现出密切的相关性。甘薯多糖能显著提高荷瘤小鼠中血清SOD的活性,降低MDA含量。结论]甘薯多糖具有较强的抗氧化能力,其抗氧化性机制主要是通过增强SOD等抗氧化酶活性,从而清除自由基,降低MDA含量。

Study on the Antioxidation of Polysaccharide from Sweet Potato

Objective The aim of the research was to discuss the scavenging mechanism of polysaccharide from sweet potato(PSP)on active oxygen free radicals.Method With the isolated and purified PSP as test materials,the chemical model systems were used to produce and ·OH.resp.And the scavenging capability of PSP on free radicals,its inhibition effect on pyrogallol autoxidation and the effects of PSP on SOD activity and MDA content in tumor-bearing mice were studied.Result In vitro,PSP both had scavenging effects on O2-· and ·OH and it had a positive correlation with the PSP concentration.In vivo,the antioxidation of PSP had a close correlation with the antitumor effect.PSP could increase the activity of serum SOD and reduce MDA content in tumor-bearing mice significantly.Conclusion PSP had stronger antioxidant capacity.Its antioxidant mechanism was scavenging free radicals and reducing MDA content mainly through strengthening the activities of antioxidases such as SOD.