Carotenoids are tetraterpenoid consists of series of conjugated double bonds and they are liable to enzymatic or non-enzymatic oxidative breakdown or isomerization at various physiological conditions. Further, oxidation or isomerization can also occur during food processing and other chemical reactions. In general, biotransformation of carotenoids occurs through hydroxylation, epoxidation, isomerization and oxidation-reduction in vivo. Central cleavage of carotenoids gives C20 compounds retinoids, eccentric cleavages gives smaller fragments, notably C10, C13 and C15 compounds with end group. Carotenoids are associated with reduced incidence of major health related problems such as vitamin-A deficiency, age-related macular degeneration, atherosclerosis, cancers and other chronic diseases.
Bangalore Prabhashankar Arathi and Rangaswamy Lakshminarayana