ABSTRACT
Carotenoids are a family of fat-soluble compounds that provide red and orange colors to plants, algae, and cyanobacteria. Whereas several vegetables such as tomatoes are rich sources of carotenoids, animal sources of carotenoids include salmonid sh, crustacean shell sh, calf liver, and eggs. Carotenoids participate in light harvesting and are essential for photo-protection in photosynthetic plant tissues. Carotenoids are synthesized by photosynthetic organisms including plants, and also by some nonphotosynthetic bacteria and fungi. Animals, including humans, do not synthesize carotenoids de novo and rely upon the diet as the source of these compounds. Over 600 carotenoids have been identi ed till date. The color of carotenoids is due to a chromophore consisting of a chain of conjugated double bonds. Diversity in carotenoids is essentially due to these numerous conjugated double bonds and the cyclic end groups in their elongated structures, which allow a variety of stereoisomers with different chemical and physical properties. Whereas detailed chemistry of carotenoids can be found elsewhere, this chapter essentially discusses their availability from marine organisms and biological functions, which make them potential nutraceutical molecules.
