Curcuminoids as potent inhibitors of lipid peroxidation.

Earlier studies showed that curcumin is a potent inhibitor iron-catalysed lipid peroxidation. Demethoxycurcumin, bisdemethoxycurcumin and acetylcurcumin were tested for their ability to inhibit iron-stimulated lipid peroxidation in rat brain homogenate and rat liver microsomes. Comparison of the results with curcumin showed that all compounds are equally active, and more potent than alpha-tocopherol. These results showed that the methoxy and phenolic groups contribute little to the activity. Spectral studies showed that all compounds could interact with iron. Thus, the inhibition of iron-catalysed lipid peroxidation by curcuminoids may involve chelation of iron.