The antioxidant activity of Flavonoids Isolated from Corylus colurna

A natural mixture of flavonoids (F4) was isolated from Corylus colurna leaves. In this study the antioxidant and the free radical scavenging activities of this mixture have been investigated. It was found that F4 had a strong antioxidant activity comparable to that of quercetin and myricetin and higher than that of rutin. F4 is a potent superoxide radical scavenger, more efficient than quercetin and myricetin or their mixture. F4 is also a strong inhibitor of ischaemia/reperfusion‐induced peroxidation in the brain and liver. In addition to these advantages F4 had low toxicity and can be readily isolated. All these advantages make it an alternative to the more toxic synthetic antioxidants for the treatment of pathological conditions in which free radicals are involved.