DPPH·法评价杜仲叶提取物的抗氧化活性  

Evaluation of Antioxidant Activity of Eucommia ulmoides Leaf Extracts by DPPH· Assay

作　　者：苑子夜[1] 苏印泉[1] 张强[1] 朱铭强[1] 中泽庆久[2] 堤雅史[2] 

机构地区：[1]西北农林科技大学林学院,陕西杨陵712100 [2]大阪大学

出　　处：《西北林学院学报》2011年第6期119-123,共5页Journal of Northwest Forestry University

基　　金：中日合作课题(K332020908);陕西省日元贷款项目(K332020023)

摘　　要：采用超声波法提取杜仲叶抗氧化物质,用DPPH.法评价其抗氧化活性。采用不同极性溶剂对最佳提取条件下的提取物进行萃取,测定不同极性萃取物中的总多酚和总黄酮含量及DPPH.清除率。结果表明:超声波法的最佳提取工艺为:60%乙醇,料液比1∶15,提取温度60℃,提取时间30min,此工艺条件下DPPH.清除率为91.01%。杜仲叶抗氧化活性物质主要存在于其弱极性的乙酸乙酯部分,该部分100μg.mL-1质量浓度样液的DPPH.清除率达92.28%,强于相同质量浓度的BHT,与相同质量浓度的Vc无显著差异。相关分析表明,杜仲叶抗氧化活性的主要物质基础为总多酚和总黄酮。The antioxidant components of Eucommia ulmoides leaves were extracted by ultrasonic-assisted method and their antioxidant activities were investigated by scavenging DPPH · The extracts obtained from optimum technological conditions were further extracted by different polar organic solvents and the contents of total phenolic compounds, total flavonoids and DPPH radical scavenging activity were determined. The results showed that the optimal parameters of the ultrasonic-assisted extraction were as follows： ethanol concentration 60%, solid to liquid ratio 1 ： 15, temperature 60℃and extracting time 30 rain. Under these conditions, the clearance rate to DPPH · were 91.01% The bioactive antioxidants of E. ulmoides leaves were mainly attributed to the ethyl acetate fraction. The percentage of scavenging DPPH radical of the sample of the ethyl acetate fraction with the concentration of 100μg·mL-1 was 92.28%, stronger than those of BHT （p〈0.05） and no significant differences compared with those of Vc. The result of correlation analysis showed that the strong antioxidant activity mainly resulted from the high contents of the total phenols and total flavonoids.

关 键 词：杜仲叶 抗氧化活性 提取工艺 DPPH· 总多酚 总黄酮 

分 类 号：S789.4[农业科学—林学]