Antioxidant Properties of Zn(II) and Fe(III) Complexes with Flavonols

Abstract

The antioxidant activity of Zn(II) and Fe(III) complexes with synthetic derivatives of flavonol was evaluated by 2,2-diphenyl-1-picrylhydrazyl radical scavenging method. The Zn(II)-flavonol complexes show antioxidant properties comparable to those of the parent flavonols. It has been revealed that complexes of flavonols with ferric ions are stronger than that with zinc ions. It has been found that iron substitutes zinc in Zn(II)–flavonol complex and binding of metal-prooxidant by flavonol occurs. The Fe(III)-flavonol complexes are potential free-radical scavengers with the same activity against free stable radical as the initial flavonols.