银杏叶、乌饭树叶和桑叶粗黄酮的抗氧化性研究

Study on Antioxidant Activity of Crude Flavonoids from Ginkgo biloba Leaves, Vaccinium bracteatum Thunb. Leaves and Mulberry Leaves

本文用70%乙醇浸提银杏叶、乌饭树叶和桑叶中的粗黄酮,测定提取物对DPPH自由基和超氧阴离子自由基的清除能力。结果表明,自由基清除能力随料液比的提高而增大。DPPH自由基清除能力大小依次为:乌饭树叶>桑叶>银杏叶,超氧阴离子自由基清除能力大小依次为:银杏叶>桑叶>乌饭树叶。银杏叶、乌饭树叶和桑叶中的粗黄酮均有一定的抗氧化能力,可作为天然抗氧化剂开发利用。

Crude flavonoids were extracted from Ginkgo biloba leaves, Vaccinium bracteatum Thunb. leaves and mulberry leaves with 70% ethanol. Their scavenging ability to DPPH radicals and superoxide anion radicals were investigated. The results showed that the free radical scavenging ability increased with the improvement of solid-liquid ratio. The scavenging ability to DPPH radicals in turn was Vaccinium bracteatum Thunb. leaves>mulberry leaves >Ginkgo biloba leaves. In the case of superoxide anion radicals the order is Ginkgo biloba leaves >mulberry leaves >Vaccinium bracteatum Thunb. leaves. The crude flavonoids in Ginkgo biloba leaves,Vaccinium bracteatum Thunb. leaves and mulberry leaves all have antioxidant activity, and can be developed and utilized as natural antioxidants.