Isoprenoid hydrocarbon consisting of six isoprene units; in linear form an excellent antioxidant; in cyclic form a principal constituent of the sterol nucleus of cholesterol.

Squalene is a natural organic compound originally obtained for commercial purposes primarily from shark liver oil, though there are botanic sources as well, including rice bran, wheat germ, and olives. All higher organisms produce squalene, including humans. It is a hydrocarbon and a triterpene.

A natural skin penetration enhancer that facilitates absorption of active ingredients.