C-26 and C-30 Apocarotenoids from Seeds of Ditaxis heterantha with Antioxidant Activity and Protection against DNA Oxidative Damage

Abstract

Carotenoids are composed of isoprene units, whose conjugated double bonds are responsible for their distinctive color. Most of the structural variations of carotenoids are found in the rings, whose double bonds are sensitive to oxidation, leading to the formation of apocarotenoids. For a symmetrical carotenoid, such as â-carotene, there are nine possible outcomes of a single bond scission due to oxidation. Apocarotenoid formation may be the result of nonspecific mechanisms such as lipoxygenase oxidation and photo-oxidation, as well as of specific mechanisms where particular dioxygenases operate in the formation of compounds such as vitamin A, abscisic acid, aromatic compounds, and pigments.