平菇菌粗多糖的抗氧化活性研究

采用深层发酵技术生产平菇粗多糖，时其清除DPPH自由基、羟自由基的能力、铁离子螯合能力以及还原力进行了比较分析。结果表明：菌丝体粗多糖和发酵液粗多糖均具有较强的抗氧化能力，但2种多糖的抗氧化能力存在差异；茵丝体粗多糖清除DPPH自由基的能力较强，其EC。。值为2．20mg／mL；发酵液粗多糖清除羟自由基的能力、铁离子螯合能力以及还原力较强，其EC50值分别为0．72mg／mL、3．32mg／mL和7．91mg／mL。在一定的浓度范围内，多糖的浓度增加，其抗氧化能力也随之增强，呈量效依赖关系。

Studies on the antioxidant activities of crude polysaccharides from Pleurotus ostreatus

Crude polysaccharides were prepared from Pleurotus ostreatus by submerged fermentation technology, and its a- bility to remove the free radical of DPPH and hydroxyl, iron ion chelating ability and reducing power were analyzed com- paratively. The results showed that a strong antioxidant capacity was presented in both of crude polysaccharides from myce- lium and crude polysaccharides from fermentation medium, however there were differences on antioxidant capacity between the two kinds of polysaccharides. The ability of removing DPPH free radical for crude polysaccharides from mycelium in- tracellular was stronger, and its ECs0value was 2.20 mg/mL; however, crude polysaccharides from fermentation medium had stronger capacity of removing hydroxyl free radical, iron ion chelating ability and reducing powers, and its EC50values were 0. 72 mg/mL, 3.32 mg/mL and 7.91 mg/mL, respectively. Within a certain range of polysaccharide concentration, the antioxidant ability of polysaccharides would enhance with the increase of polysaccharide concentration in the manner of dose-dependent.