Quantitative Relationships Between Structure and Ability of Flavonoids to Reduce Ferric Complex

Abstrakt

In various in vitro and in vivo studies it was shown that flavonoids exhibit a wide range of biological activities. In the present study, antioxidant activity of 13 flavonoids was evaluated using the ferric reducing antioxidant power (FRAP) assay, which directly determines the reducing capacity of the compounds tested. The structure – antioxidant activity relationship showed that the presence of double bond between C2 and C3 and of the OH group on C3 plays an important role. The antioxidant effect increases with increasing number of OH groups in the flavonoid. Their biological activity was correlated with nine physicochemical parameters. The sum of charges on the oxygen atoms, hydration energy and refractivity of the compounds proved to be the best descriptors of the antioxidant activity.