@misc{oai:repo.qst.go.jp:00068975,
 author = {川島, 知憲 and 中西, 郁夫 and 大久保, 敬 and Ｍａｎｄａ, Ｓｕｓｈｍａ and 福原, 潔 and 奥田, 晴宏 and 小澤, 俊彦 and 安西, 和紀 and 福住, 俊一 and その他 and 中西 郁夫 and Ｍａｎｄａ Ｓｕｓｈｍａ and 小澤 俊彦 and 安西 和紀},
 month = {Jun},
 note = {Antioxidants, such as catechin and vitamin E, are known to act as a radical-scavenger against hydroxyl and peroxyl radicals in the human body, where there are various metal ions such as sodium, ferric, and magnesium ions.  Thus, metal ions may affect the radical-scavenging activity of antioxidants.  In fact, it was reported that mixture of stem bark extract from selected species of Mangifera indica L. (Vimang) and Fe3+ showed higher radical-scavenging activity than Vimang alone.  Curcumin is a main and the most important yellow color component of turmeric.  Curcumin has been found to show antitumor and strong antioxidative activities.  Among these, antioxidative activity is believed to be due to two 4-propenylphenol moieties in its molecule.  On the other hand, curcumin also possesses an enolic structure, which may interact with metal ions in biological systems.  A complex formation between curcumin and metal ions may affect the electron distribution in the curcumin molecule, resulting in change in the radical-scavenging activity of curcumin.  Thus, the objective of this study is to clarify the interaction and the effect of radical-scavenging activity between curcumin and bio-related metal ions.
When curcumin was added to an acetonitrile solution of 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical, the absorption band at 519 nm due to DPPH radical immediately decreased.  This indicates that DPPH radical is efficiently scavenged by curcumin.  The scavenging rate constant was significantly decreased in the presence of magnesium ion, suggesting that curcumin interacts with magnesium ion.  In fact, the addition of magnesium ion into the acetonitrile solution of curcumin resulted in the spectral change.  Therefore, the radical-scavenging activity of the magnesium complex of curcumin may be lower than that of curcumin., 第17回金属の関与する生体関連反応シンポジウム},
 title = {クルクミンによるラジカル消去反応における生体関連金属イオンの効果},
 year = {2007}
}