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| Section2 = }} | Section2 = }} A curcuminoid is a linear diarylheptanoid, with molecules such as curcumin or derivatives of curcumin with different chemical groups that have been formed to increase solubility of curcumins and make them suitable for drug formulation. These compounds are natural phenols and produce a pronounced yellow color. Many curcumin characters are unsuitable for use as drugs by themselves. They have poor solubility in water at acidic and physiological pH, and also hydrolyze rapidly in alkaline solutions. Therefore, curcumin derivatives are synthezised to increase their solubility and hence bioavailability. Curcuminoids are soluble in dimethyl sulfoxide (DMSO), acetone and ethanol, but are poorly soluble in lipids. It is possible to increase curcuminoid solubility in aqueous phase with surfactants or co-surfactants. Curcumin derivatives have been synthesized that could possibly be more potent than curcumin itself. Most common derivatives have different substituents on the phenyl groups.〔 There is an increasing demand of late for demethoxycurcumin and other curcuminoids because of their recently discovered biological activity.〔 == Cyclodextrins == Curcuminoids form a more stable complex with solutions which contain cyclodextrin towards hydrolytic degradations. The stability differs between size and characterzation of the cyclodextrins that are used.〔 Dissolution of demethoxycurcumin, bisdemethoxycurcumin and curcumin are greatest in the hydroxypropyl-γ-cyclodextrin (HPγCD) cavity. The curcuminoids which have a substituent connected to the phenyl groups show more affinity for the HPγCD compound. Degradation rate is depended on pH of the solution and how much protection the cyclodextrins provide the curcuminoids. The derivatives are usually more stable than curcumin against hydrolysis in cyclodextrin solution. No covalent bonds are present between the cyclodextrins and the curcuminoids so they are easily released from the complex by simple solvent effects.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「curcuminoid」の詳細全文を読む スポンサード リンク
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