波谱学杂志2011，Vol.28Issue(4)：479-489,11.
新型羟基和醌碳自由基产生的分子机理
A Novel Mechanism for Metal-Independent Production of Hydroxyl Radicals and Carbon-Centered Quinone Ketoxy Radicals
摘要
Abstract
The hydroxyl radical (·OH) has been considered to be one of the most reactive oxygen species produced in biological systems. It has been shown that ·OH can cause oxidative damage to DNA and other macromolecules. One of the most widely accepted mechanisms for ·OH production is through the transition metal-catalyzed Fenton reaction. Pentachlorophenol (PCP) has been widely used as a wood preservative. Using e-lectron spin resonance (ESR) secondary spin-trapping methods, we found that ·OH can be produced by H2O2 and tetrachloro-1,4-benzoquinone (TCBQ) (one of the major carcinogenic metabolites of PCP) independent of transition metal ions. Further studies showed that TCBQ, but not its corresponding semiquinone radical, the tetrachlorosemi-quinone radical, is essential for ·OH production. Based on these data, we propose that ·OH production by H2O2 and TCBQ is through the following novel mechanism: a nucle-ophilic attack of H2O2 to TCBQ, forming a trichloro-hydroperoxyl-1,4-benzoquinone intermediate, which decomposes homolytically to produce ·OH. Through complementary application of ESR spin-trapping and other methods, we also detected and identified, for the first time, a novel carbon-centered quinone ketoxy radical.关键词
电子自旋共振(ESR)自旋捕获/羟基自由基/五氯酚/四氯苯醌/过氧化氢/以碳为中心的醌自由基Key words
electron spin resonance spin-trapping method/ hydroxyl radical/ pentachlorophenol/ tetrachloro-1/ 4-benzoquinone/ hydrogen peroxide/ carbon-centered quinone ketoxy radical分类
数理科学引用本文复制引用
朱本占,覃浩,黄春华..新型羟基和醌碳自由基产生的分子机理[J].波谱学杂志,2011,28(4):479-489,11.基金项目
国家重点基础研究发展计划(“973”计划)资助项目(2008CB418106) （“973”计划）
中国科学院“百人计划”资助项目 （）
国家自然科学基金资助项目(20925724,20777080,20877081,20890112,20921063). （20925724,20777080,20877081,20890112,20921063）
