5种多孔菌发酵胞外多糖抗氧化性能研究

Antioxidant Properties of Exopolysaccharide From Five Different Polyporales

选取小孔硬孔菌、硬毛栓孔菌、二年残孔菌、银杏多孔菌和血红密孔菌为菌种,发酵制得了5种多孔菌胞外多糖(EPSⅠ~Ⅴ)并进行了分离纯化.通过抑制自由基氧化DNA及捕获自由基反应探究了5种EPS的抗氧化性能和还原能力,对比确定了不同多孔菌EPS抗氧化活性差异.结果表明:5种多孔菌EPS均能够抑制自由基氧化DNA并捕获自由基,但抗氧化性能强弱存在规则性差异.在6个测试体系中,5种EPS的抗氧化性能排序基本一致,为EPSⅣ> EPSⅤ> EPSⅡ> EPSⅠ> EPSⅢ,其中,在抑制HO·、GS·和AAPH氧化DNA反应体系中,银杏多孔菌EPS(EPSⅣ)浓度为40mg/L时,相对空白TBARS吸光度百分数分别可达44.9%、32.2%和64.4%;EPSⅣ对ABTS+·、DPPH·和galvinoxyl·三种自由基的清除率分别高达52.7%、63.2%和83.9%,表现出优异的抗氧化活性,多孔菌EPS的抗氧化性能与其构型高度相关.

Five fermented and purified exopolysaccharides(EPSⅠ~Ⅴ)from Rigidoporus microporus,Abortiporus biennis,Funalia trogii,Ginkgo polypores and Rigidoporus microporus(Fr.)Overh,were selected as the research objects.The antioxidant activity and reducing ability of the 5 EPS were tested by inhibiting free radicals to initiate DNA oxidation reaction and quenching the free radical reaction system.The results showed that all the five EPSs from polyporales have ability to inhibit the DNA oxidation reaction initiated by free radicals and capture free radicals.At the same time,there are regular differences in their antioxidant properties.In the six test systems,the antioxidant properties of the five EPSs are basically ranked as EPSⅣ>EPSⅤ>EPSⅡ>EPSⅠ>EPSⅢ.Among them,the EPS from Ginkgo polypores(EPSⅣ)shows excellent antioxidant activity.The EPSⅣ,at a concentration of 40 mg/mL,can inhibit the DNA oxidation reaction system initiated by HO·,GS·and AAPH.The absorbance percentages of TBARS,compared to the blank sample,can reach 44.9%,32.2%and 64.4%.The scavenging rates of ABTS+·,DPPH·and galvinoxyl·are as high as 52.7%,63.2%and 83.9%.The antioxidant properties of EPS from polyporales are highly correlated with its monosaccharide configuration.