What is "squalene"

n. (context organic compound English) A triterpene hydrocarbon found in shark liver oil and in human sebum; it plays a role in the biosynthesis of steroids.

Squalene is a natural 30-carbon organic compound originally obtained for commercial purposes primarily from shark liver oil (hence its name), although plant sources (primarily vegetable oils) are now used as well, including amaranth seed, rice bran, wheat germ, and olives. It is also found in high concentrations in the stomach oil of birds in the order Procellariiformes. All plants and animals produce squalene as a biochemical intermediate, including humans.

Squalene is a hydrocarbon and a triterpene, and is a natural and vital part of the synthesis of all plant and animal sterols, including cholesterol, steroid hormones, and vitamin D in the human body.

Squalene is used in cosmetics, and more recently as an immunologic adjuvant in vaccines. Squalene has been proposed to be an important part of the Mediterranean diet as it may be a chemopreventive substance that protects people from cancer.