Figure 1

Chemical structure of curcumin. Curcumin (diferuloylmethane) is the active principle of the perennial herb Curcuma longa also known as turmeric (A) and is extracted from its roots (B). Molecular structure of curcumin (C). Curcumin-based products are available as dietary supplements (D). Curcuma longa photos © Merlin Willcox.