Desmethoxycurcumin is a curcuminoid found in turmeric.Commercial grade curcumin is widely used as a yellow coloring agent and spice in foods. In the present study topical application of commercial grade curcumin, pure curcumin or demethoxycurcumin had an equally potent inhibitory effect on 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced increases in ornithine decarboxylase activity and TPA-induced tumor promotion in 7,12-dimethylbenz[a]anthracene-initiated mouse skin. Bisdemethoxycurcumin and tetrahydrocurcumin were less active. In additional studies we found that commercial grade curcumin, pure curcumin, demethoxycurcumin and bisdemethoxycurcumin had about the same potent inhibitory effect on TPA-induced inflammation of mouse ears, as well as TPA-induced transformation of cultured JB6 (P+) cells. Tetrahydrocurcumin was less active.
-O919.gif)