a-carotene

β-Carotene (Provitamin A) is a naturally-occurring retinol (vitamin A) precursor obtained from certain fruits and vegetables with potential antineoplastic and chemopreventive activities. As an anti-oxidant, beta carotene inhibits free-radical damage to DNA.

Lycopene (ψ,ψ-Carotene) is a linear, unsaturated hydrocarbon carotenoid, the major red pigment in fruits such as tomatoes, pink grapefruit, apricots, red oranges, watermelon, rosehips, and guava. As a class, carotenoids are pigment compounds found in photosynthetic organisms (plants, algae, and some types of fungus), and are chemically characterized by a large polyene chain containing 35-40 carbon atoms; some carotenoid polyene chains are terminated by two 6-carbon rings. In animals, carotenoids such as lycopene may possess antioxidant properties which may retard aging and many degenerative diseases. As an essential nutrient, lycopene is required in the animal diet.

Ketoisophorone (2,6,6-Trimethyl-2-cyclohexene-1,4-dione) is the major ingredients of saffron spice. It is a cyclic olefin and was reported as a product of the thermal degradation of β-carotene in aqueous suspension.

α-Carotene is isolated from yellow-orange and dark-green vegetables. α-Carotene is used as an anti-metastatic agent or as an adjuvant for anti-cancer drugs.

Dihydro-β-erythroidine hydrobromide(DHβE) is a potent, oral active and competitive antagonist of neuronal nicotinic acetylcholine receptors (nAChRs). Dihydro-β-carotene hydrobromide showed selectivity to α4β4 and α4β2nAChR, with IC50 of 0.19 and 0.37 μM,

9-cis-Retinal is a natural retinoid. Dietary 9-cis-β-carotene generates 9-cis-retinoids via cleavage into 9-cis-retinal. 9-cis Retinal binds to CRBP-I and CRBP-II (Kds: 8 nM and 5 nM). It expedites differentiation and maturation of rod photoreceptors in r

Retinyl acetate (Vitamin A acetate) is a group of unsaturated nutritional hydrocarbons, that contains retinal, retinol, retinoic acid, and several provitamins A carotenoids, among which beta-carotene is the most important.