32株银杏内生真菌清除DPPH自由基活性的比较研究

Comparison of DPPH radical scavenging activities between 32 strains of endophytic fungus isolated from Chinese Ginkgo biloba L

采用液体摇瓶培养的方法,以DPPH自由基清除率为指标,对32株银杏内生真菌发酵液的甲醇提取物抗氧化活性进行初筛,不同菌株清除DPPH自由基活性差异较大,其中4株菌株DPPH自由基清除率显著高于其他菌株,分别为96.68%、96.09%、85.32%和84.48%.在此基础上,对8株DPPH自由基清除率较高菌株菌丝体的甲醇、乙酸乙酯、异丙醇、水4种溶剂提取物的DPPH自由基清除率进行比较,结果表明,甲醇和水提取效果较好,优于乙酸乙酯和异丙醇,其中GCZX015菌株菌丝体甲醇提取物DPPH自由基清除活性最强为93.97%,GCZX018菌株菌丝体异丙醇提取物DPPH自由基清除活性最低,仅为0.11%.

The free radical scavenging activities of methanol extracts from 32 strains isolated from Ginkgo biloba were compared in shaking flask by the method of DPPH. The results showed that the radical scav- enging activities were different. The DPPH radical scavenging activity of four strains,signicantly higher than others,reached 96.68%, 96.09%, 85.32% and 84.48%, respectively. On this basis, eight strains which have higher radical scavenging activity were choosn. The DPPH radical scavenging activities of their dry mycelia extracts extractd by the methanol, ethyl acetate,isopropyl alcohol and water were com- pared. The results revealed that the effects of extracts by methanol and water were better than ethyl ac- etate and isopropyl alcohol. Methanol extracts of mycelia of GCZX015 was the highest, reaching 93. 97% and isopropyl alcohol extracts of mycelia of GCZX015 was the lowest, only reached 0.11%.