Antioxidant effect of capsaicinoids on the metal-catalyzed lipid peroxidation

Abstract

Antioxidant action of capsaicinoids was analyzed in relation to the role of transition metal. Capsaicin and dihydrocapsaicin inhibited the iron-mediated lipid peroxidation and copper-dependent oxidation of low density lipoprotein (LDL). Copper-dependent oxidation of LDL was also inhibited by addition of Superoxide dismutase, suggesting that Superoxide radical is essential for the oxidation process. Capsaicinoids showed a potent copper-reducing activity. Antioxidant properties of capsaicinoids can be explained by forming complexes with the reduced metals, which are inert to oxygen molecule, and also by chain-breaking reaction that donates hydrogen to radical intermediates.