Antioxidant activity and chemical constituents of edible flower of Sophora viciifolia

► We evaluated the antioxidant activities of crude extract and its derived soluble fractions from the flower of Sophora viciifolia in five different test systems. ► Correlation analysis suggested that the flavonoids might be the major contributors for the high antioxidant activity. ► We obtained 11 compounds and evaluated the antioxidant capacities of compounds 3-7. ► We determined the contents of compound 3 and 4, and 3 might play an important role for the antioxidant activity of this flower.