Canthaxanthin (red diketocarotenoid or 4, 4′-diketo-β-carotene), is a common xanthophyll found naturally in microorganisms and marine organisms, as well as in certain animals. It acts as an antioxidant in living organisms. The potential antioxidant activity of canthaxanthin is due to the presence of conjugated double bonds in its structure. It finds applications in various fields including poultry, fishery, cosmetics, medicine, and pharmaceuticals. In food industries, canthaxanthin can be used as a coloring agent.