Study on Antioxidant Activity of Flavonoids from Sophora japonica Linn Leaves

The aim of this study was to investigate the antioxidant activity of flavonoids of Sophora japonica leaves using ABTS removal system,DPPH removal system,H2O2/Fe2+ salicylic system,nitroso removal system,prussian blue method and pyrogalla autoxidation system.Rutin and Vitamin C(Vc)were used as the controls.The results showed that the flavonoids of S.japonica leaves had different ability of scavenging on different free radicals.At concentration of 50 μg/mL,the scavenging rates of flavonoids from S.japonica leaves on ABTS,DPPH,·OH,NO-2and O-·2 were 62.09%,47.70%,43.28%,22.11% and 21.83%,respectively.The results showed that,the ABTS+ and DPPH+ radical scavenging ability of flavonoids S.japonica were lower than rutin and Vc;the NO-2,·OH radical scavenging ability of flavonoids from S.japonica were higher than rutin and Vc;the O-·2 radical scavenging ability of flavonoids from S.japonica was in between rutin and Vc.Meanwhile,the flavonoid extracts exhibited strong reducing power.These results demonstrated that flavonoids extracted from S.japonica Leaves can be used as a natural antioxidant,which can be applied in both healthy medical and food industry.