Products
Astaxanthin is commercially available in many countries as a dietary supplement in the form of capsules (e.g., Novaxanthine by Bionaturis, 4 mg). It is contained in krill oil, which is also traded in the form of capsules. Astaxanthin is not registered as a drug.
Structure and properties
Astaxanthin (C40H52O4, Mr = 596.8 g/mol) is a lipophilic carotenoid and, like lutein and zeaxanthin, belongs to the xanthophyll family, which is not metabolized to vitamin A like beta-carotene and is distinguished from other carotenoids by the oxygen in the molecule. Astaxanthin has two carbonyl groups, two hydroxyl groups and conjugated double bonds, which absorb light and are responsible for its red color. In nature, it is often present esterified or bound because free astaxanthin is sensitive to oxidation. Astaxanthin is ubiquitous in nature and is found primarily in the sea. The pigment gives salmon, shrimp, krill, lobster, crabs their orange to red color and is also found in some birds. It is formed by microalgae such as and phytoplankton and accumulates in the food chain. It is extracted from natural sources (mainly ) or produced synthetically.
Effects
Astaxanthin is strongly antioxidant. Studies have demonstrated antitumor, antidiabetic, antihypertensive, anti-inflammatory, and organ-protective properties. However, there is a lack of appropriate clinical studies as required for drug approval.
Indications
Astaxanthin is taken as a dietary supplement for its potential health-promoting properties. In the food and fish industries, it is an additive used in fish farms to color the flesh, for example, of salmon and rainbow trout.
