Astaxanthin

Astaxanthin is a naturally occurring red carotenoid belonging to the xanthophyll class of derivatives. It was first discovered in crustaceans such as shrimp and crab, from which it derives its name. Its chemical formula is C₄₀H₅₂O₄, with a molecular weight of 596.84 g/mol and CAS number 472-61-7. Astaxanthin is recognized as one of the most powerful antioxidants in nature, with antioxidant activity approximately 550 times stronger than vitamin E and 60 times stronger than lycopene.

The unique molecular structure of astaxanthin features polar groups (hydroxyl and keto groups) at both ends and a conjugated polyene chain in the middle. This amphiphilic structure enables it to dissolve in both water and lipids, allowing it to orient across cell membranes and efficiently scavenge free radicals. Natural astaxanthin exists primarily in the 3S,3'S stereoisomeric form, which exhibits higher biological activity than synthetic mixtures.