Betacarotene

Beta-carotene is an organic compound - a terpenoid, a red-orange pigment abundant in plants and fruits. As a carotene with β-rings at both ends, it is the most common form of carotene. It is a precursor (inactive form) of vitamin A. Being highly conjugated, it is deeply colored, and as a hydrocarbon lacking functional groups, it is very lipophilic.

The structure was deduced by Karrer et al. In nature, β-carotene is a precursor to vitamin A via the action of β-carotene dioxygenase. β-carotene is also the substance in carrots that colours them orange. β-Carotenoid is biosynthesized from geranylgeranyl pyrophosphate.