Carotenoids are terpenoid compounds that besides their typical pigmenting characteristics (yellow, orange or red pigments), function as precursors of molecules with biological activity intervening in different vital biological and physiological processes.

Over 700 different carotenoids have been recognized in nature. Carotenoids are classified in two major groups:

Carotenes

Examples of carotenes include: Carotene, Lycopene

Xanthophylls (oxygenated derivatives of the carotenes)

Examples of xanthophylls include: Lutein, Zeaxanthin, Capsanthin, Astaxanthin and Cantaxanthin

Carotenoids are widely distributed in nature. They are produced in nature by photosynthetic and enzymatic reactions.

Carotenoids act as effective antioxidants in most living organism. They have the capability to chelate free radicals that are produced in metabolic reactions at cellular level, avoiding tissue degradation.