Mechanisms and Structural Specificity of Hydrogen Peroxide Formation during Oxidation of Catechins.

• NAKAYAMA Tsutomu

  School of Food and Nutritional Sciences, University of Shizuoka

• ICHIBA Megumi

  School of Food and Nutritional Sciences, University of Shizuoka

• KUWABARA Miho

  School of Food and Nutritional Sciences, University of Shizuoka

• KAJIYA Katsuko

  School of Food and Nutritional Sciences, University of Shizuoka

• KUMAZAWA Shigenori

  School of Food and Nutritional Sciences, University of Shizuoka

抄録

Hydrogen peroxide (H₂O₂) formed in aqueous solutions of tea catechins such as epicatechin (EC), epicatechin gallate (ECg), epigallocatechin (EGC), and epigallocatechin gallate (EGCg) was measured by an HPLC method. The amount of H₂O₂ formed depended on their chemical structures, pH, temperature and incubation time. The gallyl moiety in the B-ring of the gallocatechins, namely EGC and EGCg, mainly contributed to the H₂O₂ formation. Superoxide dismutase inhibited oxidation of the gallocatechins and, consequently, the H₂O₂ formation. Cytotoxic effects were investigated by a colony formation assay with Chinese hamster V79 cells, and the effects of the gallocatechins were stronger than those of EC and ECg. The cytotoxic effects of the gallocatechins were inhibited completely by catalase and partially by superoxide dismutase. These results indicate that the gallocatechins were oxidized by superoxide, accompanied by the formation of H₂O₂, and their cytotoxic effects were ascribed to the H₂O₂ formation.<br>

収録刊行物

• Food Science and Technology Research

  Food Science and Technology Research 8 (3), 261-267, 2002

  公益社団法人 日本食品科学工学会

キーワード

• superoxide anion
• hydrogen peroxide
• catechin
• superoxide dismutase (SOD)
• epigallocatechin (EGC)
• epigallocatechin gallate (EGCg)

詳細情報

• CRID: 1390001204455921152
• NII論文ID: 10012602578
• NII書誌ID: AA11320122
• DOI: 10.3136/fstr.8.261
• COI: 1:CAS:528:DC%2BD38XptlCmsLg%3D
• ISSN: 18813984
• ISSN: 13446606
• ISSN: http://id.crossref.org/issn/13446606
• 本文言語コード: en
• データソース種別:
  • JaLC
  • Crossref
  • CiNii Articles
• 抄録ライセンスフラグ: 使用不可