{"created":"2023-05-15T14:51:32.850350+00:00","id":70464,"links":{},"metadata":{"_buckets":{"deposit":"6184cbb9-8038-48b0-a2ed-6b65ceb0de0c"},"_deposit":{"created_by":1,"id":"70464","owners":[1],"pid":{"revision_id":0,"type":"depid","value":"70464"},"status":"published"},"_oai":{"id":"oai:repo.qst.go.jp:00070464","sets":["10:28"]},"author_link":["691973","691976","691975","691977","691974","691978"],"item_10005_date_7":{"attribute_name":"発表年月日","attribute_value_mlt":[{"subitem_date_issued_datetime":"2011-06-17","subitem_date_issued_type":"Issued"}]},"item_10005_description_5":{"attribute_name":"抄録","attribute_value_mlt":[{"subitem_description":"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.\nA 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.\nX-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.","subitem_description_type":"Abstract"}]},"item_10005_description_6":{"attribute_name":"会議概要（会議名, 開催地, 会期, 主催者等）","attribute_value_mlt":[{"subitem_description":"4th International Symposium on Nutrition, Oxygen Biology and Medicine","subitem_description_type":"Other"}]},"item_access_right":{"attribute_name":"アクセス権","attribute_value_mlt":[{"subitem_access_right":"metadata only access","subitem_access_right_uri":"http://purl.org/coar/access_right/c_14cb"}]},"item_creator":{"attribute_name":"著者","attribute_type":"creator","attribute_value_mlt":[{"creatorNames":[{"creatorName":"Matsumoto, Kenichiro"}],"nameIdentifiers":[{"nameIdentifier":"691973","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"Nakanishi, Ikuo"}],"nameIdentifiers":[{"nameIdentifier":"691974","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"Ozawa, Toshihiko"}],"nameIdentifiers":[{"nameIdentifier":"691975","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"松本 謙一郎","creatorNameLang":"en"}],"nameIdentifiers":[{"nameIdentifier":"691976","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"中西 郁夫","creatorNameLang":"en"}],"nameIdentifiers":[{"nameIdentifier":"691977","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"小澤 俊彦","creatorNameLang":"en"}],"nameIdentifiers":[{"nameIdentifier":"691978","nameIdentifierScheme":"WEKO"}]}]},"item_language":{"attribute_name":"言語","attribute_value_mlt":[{"subitem_language":"eng"}]},"item_resource_type":{"attribute_name":"資源タイプ","attribute_value_mlt":[{"resourcetype":"conference object","resourceuri":"http://purl.org/coar/resource_type/c_c94f"}]},"item_title":"Method for Assessig Hydroxyl Radical Scavenging Activity","item_titles":{"attribute_name":"タイトル","attribute_value_mlt":[{"subitem_title":"Method for Assessig Hydroxyl Radical Scavenging Activity"}]},"item_type_id":"10005","owner":"1","path":["28"],"pubdate":{"attribute_name":"公開日","attribute_value":"2011-06-28"},"publish_date":"2011-06-28","publish_status":"0","recid":"70464","relation_version_is_last":true,"title":["Method for Assessig Hydroxyl Radical Scavenging Activity"],"weko_creator_id":"1","weko_shared_id":-1},"updated":"2023-05-15T20:02:39.533412+00:00"}