Flavonoids from Perilla frutescens were prepared by three extraction methods.The antioxidation activity of the flavonoids was measured with rapeseed oil as the substrate.

• 用三种方法对紫苏茎、叶中黄酮类化合物进行了提取,并以食用菜油作底物,用烘箱贮藏法测定抗氧化活性。