<unk>  is a keto-carotenoid pigment widely distributed in nature. Carotenoids belong to a larger class of phytochemicals known as terpenoids. The chemical formula of<unk>  is C40H52O2. It was first isolated in edible mushrooms. It has also been found in green algae, bacteria, crustaceans, and bioaccumulates in fish such as carp, golden grey mullet, seabream and trush wrasse.<unk>  is associated with E number E161g and is approved for use as a food coloring agent in different countries, including the United States and the EU; however, it is not approved for use in Australia and New Zealand. It is generally authorized for feed applications in at least the following countries: US, Canada, EU. In the EU,<unk>  is allowed by law to be added to trout feed, salmon feed and poultry feed. The European Union limit is 80 mg/kg of feedstuffs, 8 mg/kg in feed for egg laying hens and 25 mg/kg in feed for other poultry and salmonids.<unk>  is a potent lipid-soluble antioxidant. The biological functions of<unk>  are related, at least in part, to its ability to function as an antioxidant (free radical scavenging/vitamin E sparing) in animal tissues.
Canthaxanthin
Epoetin beta
Fosdenopterin
Eutropoflavin
Hematoporphyrin
Lipochrome
Ophanin
Tetrahydrobiopterin