黄荆子总黄酮不同极性部位的体外抗氧化活性分析

Research on Antioxidant Activity in Vitro of Different Fractions from Total Flavonoids of Vitex negundo L. Seeds

目的本实验采用溶剂萃取法对黄荆子中总黄酮进行初步分离,采用体外抗氧化方法来筛选出主要的抗氧化活性部位。方法利用70%乙醇超声提取总黄酮,分别用氯仿、乙酸乙酯、正丁醇萃取,得到不同极性部位,通过测定其铁还原力、总抗氧化力和对DPPH自由基清除率评价黄荆子的抗氧化活性,并同VC进行了比较。结果黄荆子总黄酮四个不同极性部位均具有不同程度的抗氧化活性,且该活性与总黄酮浓度之间有较好的相关性。结论四个部位中氯仿部分抗氧化活性最高,氯仿部位铁还原力、总抗氧化力高于VC,清除DPPH自由基能力略低于VC。

Objective To study the antioxidant activity in vitro of different fractions from total flavonoids of Vitex negundo L. seeds. Vitex negundo L. seeds were extracted and separated into four parts with different polarity. Method Ultrasonic extraction was employed to extract flavonoids ingredients with 70% ethanol. Different polars could be obtained by the extraction with chloroform, ethyl acetate and n-butanol. Three methods including ferric reducing power, total antioxidant power and 2, 2-diphenyl-1-picrylhyd-razyl radical scavenging assay were performed to detect the antioxidant activity, which was compared with that of vitamin C. Results The four different fractions of total flavonoids of vitex negundo L. seeds have different antioxidant activities, and there is good correlation between the antioxidant capacity and the density of flavonoids. Conclusion Among the four fractions, the chloroform layer exhibits the strongest antioxidant activities compared with ethyl acetate, n-butanol and water layer, and the iron reduction and total antioxidant forces of the chloroform layer are higher than VC, but its radical-scavenging activity is slightly lower than VC.