Antioxidant Activities of the Antheraxanthin-related Carotenoids, Antheraxanthin, 9-cis-Antheraxanthin, and Mutatoxanthins

Abstract

In this study, we investigated the antioxidant activities of antheraxanthin-related carotenoids. Antheraxanthin and 9-cis-antheraxanthin were prepared from persimmon and orange fruit, respectively, and converted to other carotenoids under acidic conditions. Resulting carotenoids were purified using preparative silica gel HPLC, and their structures were analyzed in detail by NMR spectra. Both antheraxanthin and 9-cis-antheraxanthin were found to be converted to (8R)- and (8S)-mutatoxanthin at an approximate ratio of 3:2. High antioxidant activities were observed for antheraxanthin, 9-cis-antherxanthin, (8R)-mutatoxanthin, and (8S)-mutatoxanthin, with potent lipid peroxidation inhibitory and moderate ¹O₂-quenching activities.