Curcumin (English: curcumin) is an extract from turmeric rhizome get yellow pigment. It is the most important curcumin (curcuminoid) substances, accounting for about 70 percent of curcumin, about 3% to 6% of turmeric. In addition to curcumin, this class of compounds also include Bisdemethoxycurcumin (10-20%), off-dimethoxy curcumin (10%) and hexahydro curcumin. Curcumin is orange yellow crystalline powder, with special smell, taste slightly bitter. Insoluble in water and ether, soluble in ethanol, acetone, acetic acid and propylene glycol, slightly soluble in ether with a pale green fluorescence. Under alkaline conditions reddish brown. Pale yellow under acidic conditions, dissolved in concentrated sulfuric acid yellow to red. With metal ions (especially iron ions) and forming a chelate color.
Structurally, curcumin is formed by two o-methylated phenol and a β- diketone, belonging to polyphenols. The β- diketone structure enol - keto tautomers, but in the solid state spectra proved curcumin and solution mainly enol form. Curcumin also has significant economic value and wide range of pharmacological effects, such as lowering blood pressure、Antioxidant, anti-inflammatory, anti-atherosclerosis and so on. When in 2004 found that curcumin can inhibit HIV-1 integrase activity and clinical trials for AIDS. In addition, anti-cancer is one of the main pharmacological activity of curcumin and its role of tumor suppression has been repeatedly demonstrated in many animal studies, it has become a recent specific Carcinogenesis hotspot. I. Eight efficacy of curcumin antioxidant functions to slow down the aging According to the research pointed out that ultraviolet sunlight is a major killer of skin aging, ultraviolet light can cause free radical damage to the skin's collagen elastin, thereby enabling deterioration of the skin tightness, water retention also fell, so it looks dull and prone to wrinkles.