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Method for Assessig Hydroxyl Radical Scavenging Activity
https://repo.qst.go.jp/records/70464
https://repo.qst.go.jp/records/70464f9c92b6d-da8c-4e06-9c48-8d96f66f2a12
| Item type | 会議発表用資料 / Presentation(1) | |||||
|---|---|---|---|---|---|---|
| 公開日 | 2011-06-28 | |||||
| タイトル | ||||||
| タイトル | Method for Assessig Hydroxyl Radical Scavenging Activity | |||||
| 言語 | ||||||
| 言語 | eng | |||||
| 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 |
Matsumoto, Kenichiro
× Matsumoto, Kenichiro× Nakanishi, Ikuo× Ozawa, Toshihiko× 松本 謙一郎× 中西 郁夫× 小澤 俊彦 |
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| 抄録 | ||||||
| 内容記述タイプ | Abstract | |||||
| 内容記述 | Hydroxyl radical (•OH) is the most reactive species of reactive oxygen species (ROS); therefore, •OH is one of the important player in oxidative stress. The •OH can be measured using electron paramagnetic resonance (EPR) spin-trapping method. Generally, •OH-scavenging-effect of an anti-oxidant has been estimated by a method adding the anti-oxidant and a spin-trapping agent to a •OH generation system. Fenton reaction system or irradiating UV to hydrogen peroxide (H2O2) has been often used as the •OH generation system. Using Fenton reaction system for estimating •OH-scavenging-effect, iron-chelating effect of the anti-oxidant and/or reaction of H2O2 with the anti-oxidant must be considered to estimate the •OH-scavenging-effect correctly. For using UV+H2O2 reaction system, reaction of H2O2 with the anti-oxidant and absorption of UV by the anti-oxidant must be considered for correct estimation of the •OH-scavenging-effect. X-ray irradiation to water can also generate •OH. In this simple system, estimation of the •OH-scavenging-effect of an anti-oxidant can be much easier, while reduction of spin adduct with the anti-oxidant must be considered. In this study, we are trying to propose an efficient method for estimating •OH-scavenging-effect of an anti-oxidant. A reaction mixture containing 30 mM of a spin-trapping agent (DMPO) and an arbitrary concentration of an anti-oxidant was prepared using 100 mM phosphate buffer (pH7, containing 0.05 mM DTPA). X-ray was irradiated to the reaction mixture and then amount of the •OH-spin-adduct (DMPO-OH) was measured immediately using X-band EPR spectrometer. A reaction mixture containing 60 mM was prepared and irradiated by X-ray, then the anti-oxidant was added to estimate reduction of DMPO-OH by the anti-oxidant. X-ray irradiation to the reaction mixture containing DMPO generates DMPO-OH in the reaction mixture dose dependently. Even doing the experiment under N2 gas atmosphere, no difference was obtained for amount of DMPO-OH generated compared to the experiment in the air. The DMPO-OH obtained in the reaction mixture was from •OH generated by X-ray. When anti-oxidant 1 was added to the reaction mixture, amount of X-ray induced DMPO-OH in the reaction mixture was decreased depending on the dose of the anti-oxidant 1. To determine whether the anti-oxidant 1 was really scavenging •OH, reduction of DMPO-OH caused by the anti-oxidant 1 was estimated. The anti-oxidant 1 was added to the reaction mixture containing DMPO-OH, which was previously generated by X-ray irradiation. The reduction rate of DMPO-OH by the anti-oxidant 1 was enough slow; therefore, the reducing DMPO-OH amount by adding anti-oxidant before X-ray irradiation was mainly due to scavenging •OH by the anti-oxidant 1. Anti-oxidant 2 also showed the reducing DMPO-OH amount, when the anti-oxidant 2 was added to reaction mixture before X-ray irradiation. Anti-oxidant 2, however, showed a rapid reduction of DMPO-OH, when the anti-oxidant 2 was added after X-ray irradiation. Scavenging •OH by anti-oxidant 2 can not estimated directly from the result of the experiment; however, it is possible to think that anti-oxidant 2 was a strong reductant which can be reduce relatively stable nitroxyl radical (DMPO-OH in this case). Using the method in this experiment, anti-oxidative property can be estimated using scavenging •OH and/or reducing DMPO-OH. |
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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 | 4th International Symposium on Nutrition, Oxygen Biology and Medicine | |||||
| 発表年月日 | ||||||
| 日付 | 2011-06-17 | |||||
| 日付タイプ | Issued | |||||
