Aquatic animal carotenoids

Carotenoids are yellow to red isoprenoid polyene pigments; approximately 650 carotenoids are known from bacteria, fungi, plants and animals. They occur not only as free forms but also as esters, glycosides, sulfates and carotenoproteins. A recent discovery of antitumor activity in carotenoids, such as vitamin A and β-carotene, has brought attention to marine carotenoids. This review describes the structures of 117 carotenoids isolated from sponges, coelenterates, mollusks, crustaceans, echinoderms, tunicates and fishes. The comparative biochemistry and metabolic pathways of these carotenoids are also discussed.