Astaxanthin is a natural carotenoid. Such organic fat-soluble nutrients can be found in nature. This substance is found in algae and some fish and seafood that eat algae, including salmon, crab, krill, and lobster. Astaxanthin has an intense red color. Its chemical name is 3,3-dihydroxy-4,4-diketo-β,β-carotene and its molecular formula is C40H52O4. Read More