Carotenylflavonoids, a novel group of potent, dual-functional antioxidants

Abstract

We report here on the synthesis and antioxidant properties of novel covalently linked flavonoid-carotenoid hybrids, hereinafter referred to as carotenylflavonoids. By this strategy the essential properties of the protecting systems are improved. Compared with the parent carotenoids or flavonoids, e.g. β-carotene and a hydroxyflavone, these molecular combinations exhibit improved photoprotective properties, as seen from their UV spectra, and they outperform the individual constituents in their antioxidant properties. The dual functionality is revealed from the time evolution of the peroxidation inhibition assay which clearly displays both phenolic and carotenoid-polyenic contributions to the antioxidant efficiency. Furthermore, these compounds have amphiphilic character, in contrast to symmetrical carotenes and hydroxylated flavones. The antioxidative potential of the carotenylflavonoids is high. They protect cumene against peroxidation more than β-carotene by a factor of about 2.3-2.5, and more than the individual components. ©ARKAT USA, Inc.