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ルイス酸存在下におけるフラボノイド類の酸化反応挙動
https://repo.qst.go.jp/records/71532
https://repo.qst.go.jp/records/71532e47e3496-2a2c-482c-8d4f-2a1cd3cb7201
| Item type | 会議発表用資料 / Presentation(1) | |||||
|---|---|---|---|---|---|---|
| 公開日 | 2014-11-06 | |||||
| タイトル | ||||||
| タイトル | ルイス酸存在下におけるフラボノイド類の酸化反応挙動 | |||||
| 言語 | ||||||
| 言語 | jpn | |||||
| 資源タイプ | ||||||
| 資源タイプ識別子 | http://purl.org/coar/resource_type/c_c94f | |||||
| 資源タイプ | conference object | |||||
| アクセス権 | ||||||
| アクセス権 | metadata only access | |||||
| アクセス権URI | http://purl.org/coar/access_right/c_14cb | |||||
| 著者 |
和氣, 司
× 和氣, 司× 大久保, 敬× 松本, 謙一郎× 小澤, 俊彦× 福住, 俊一× 鎌田, 正× 中西, 郁夫× 和氣 司× 大久保 敬× 松本 謙一郎× 小澤 俊彦× 鎌田 正× 中西 郁夫 |
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| 抄録 | ||||||
| 内容記述タイプ | Abstract | |||||
| 内容記述 | Flavonoids are known to show an efficient scavenging activity against 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical as a model of reactive oxygen species. However, little is known about the DPPH radical-scavenging mechanisms of flavonoids. On the other hand, Lewis acids, such as Mg(2+) and Al(3+), are known to accelerate electron-transfer reactions. In this study, we investigated the effect of Lewis acids on the radical-scavenging activity of flavonoids, as well as on their one-electron oxidation potentials (E(0)(ox)) to clarify the detailed radical-scavenging mechanisms. The rate of the DPPH radical-scavenging reaction of kaempferol, one of flavonoids, in the presence or absence of 0.1 M Mg(ClO(4))(2) or Al(ClO(4))(3) were determined by monitoring the absorbance change at 517 nm due to DPPH radical. The second-order rate constant (k) for the DPPH radical-scavenging reaction by kaempferol was decreased in the presence of the Lewis acid. The E(0)(ox) value of kaempferol was determined by second-harmonic alternating current voltammeter. Mg(2+) showed little effect on the E(0)(ox) value of kaempferol, while the E(0)(ox) value was largely shifted in the presence of Al(3+) to the positive direction. On the other hand, Al(3+) significantly changed the cyclic voltammogram of DPPH radical, while a slight change was observed in the presence of Mg(2+). These results indicate that the one-electron accepting ability of DPPH radical was significantly increased in the presence of Al(3+). These results indicate that the DPPH radical-scavenging reaction of kaempferol occurred via a hydrogen-atom transfer as the rate-determining step rather than electron transfer. |
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| 会議概要（会議名, 開催地, 会期, 主催者等） | ||||||
| 内容記述タイプ | Other | |||||
| 内容記述 | 第47回酸化反応討論会 | |||||
| 発表年月日 | ||||||
| 日付 | 2014-11-15 | |||||
| 日付タイプ | Issued | |||||
