Curcumin

Curcumin is a bright yellow chemical produced by Curcuma longa plants. It is the principal curcuminoid of turmeric (Curcuma longa), a member of the ginger family, Zingiberaceae. It is sold as an herbal supplement, cosmetics ingredient, food flavoring, and food coloring. Curcumin is a bright yellow chemical produced by Curcuma longa plants. It is the principal curcuminoid of turmeric (Curcuma longa), a member of the ginger family, Zingiberaceae. It is sold as an herbal supplement, cosmetics ingredient, food flavoring, and food coloring. Chemically, curcumin is a diarylheptanoid, belonging to the group of curcuminoids, which are natural phenols responsible for turmeric's yellow color. It is a tautomeric compound existing in enolic form in organic solvents and in keto form in water. Curcumin has no confirmed medical use in spite of efforts to find one via both laboratory and clinical research. It is difficult to study because it is both unstable and not bioavailable. It is unlikely to produce useful leads for drug development. The most common applications are as an ingredient in dietary supplement, in cosmetics, and as flavoring for foods, such as turmeric-flavored beverages in South and Southeast Asia. As a food additive for orange-yellow coloring in prepared foods, its E number is E 100 in the European Union. Curcumin incorporates several functional groups whose structure was first identified in 1910. The aromatic ring systems, which are phenols, are connected by two α,β-unsaturated carbonyl groups. The diketones form stable enols and are readily deprotonated to form enolates; the α,β-unsaturated carbonyl group is a good Michael acceptor and undergoes nucleophilic addition. Curcumin is used as a complexometric indicator for boron. It reacts with boric acid to form a red-colored compound, rosocyanine. The biosynthetic route of curcumin is uncertain. In 1973, Peter J Roughley and Donald A. Whiting proposed two mechanisms for curcumin biosynthesis. The first mechanism involves a chain extension reaction by cinnamic acid and 5 malonyl-CoA molecules that eventually arylize into a curcuminoid. The second mechanism involves two cinnamate units coupled together by malonyl-CoA. Both use cinnamic acid as their starting point, which is derived from the amino acid phenylalanine. Plant biosynthesis starting with cinnamic acid is rare compared to the more common p-coumaric acid. Only a few identified compounds, such as anigorufone and pinosylvin, build from cinnamic acid.