...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Environmental Science & Technology >Investigating Chloroperoxidase-Catalyzed Formation of Chloroform from Humic Substances Using Stable Chlorine Isotope Analysis
【24h】

Investigating Chloroperoxidase-Catalyzed Formation of Chloroform from Humic Substances Using Stable Chlorine Isotope Analysis

机译：使用稳定的氯同位素分析法研究氯过氧化物酶催化腐殖质中氯仿的形成

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Chloroperoxidase (CPO) is suspected to play an important role in the biosynthesis of natural chloroform. The aims of the present study are to evaluate the variability of the δ~(37)Cl value of naturally produced chloroform and to better understand the reaction steps that control the chlorine isotope signature of chloroform. The isotope analyses have shown that the chlorination of the humic substances (HS) in the presence of high H_3O~+ and Cl~- concentrations induces a large apparent kinetic isotope effect (AKIE = 1.010-1.018) likely associated with the transfer of chlorine between two heavy atoms, whereas in the presence of low H_3O~+ and Cl~- concentrations, the formation of chloroform induces a smaller AKIE (1.005-1.006) likely associated with the formation of an HOCl- ferriprotoporphyrin Ⅸ intermediate. As the concentration of H_3O~+ and Cl~- in soils are generally at submillimolar levels, the formation of the HOCl- ferriprotoporphyrin Ⅸ intermediate is likely rate-limiting in a terrestrial environment. Given that the δ~(37)Cl values of naturally occurring chloride tend to range between -1 and +1‰, the δ~(37)Cl value of natural chloroform should vary between - 5‰ and -8‰. As the median δ~(37)Cl value of industrial chloroform is -3.0‰, the present study suggests that chlorine isotopic composition of chloroform might be used to discriminate industrial and natural sources in the environment.
机译：氯过氧化物酶（CPO）被怀疑在天然氯仿的生物合成中起重要作用。本研究的目的是评估天然产生的氯仿的δ〜（37）Cl值的变异性，并更好地理解控制氯仿的氯同位素特征的反应步骤。同位素分析表明，在高H_3O〜+和Cl〜-浓度存在下，腐殖质（HS）的氯化会引起较大的表观动力学同位素效应（AKIE = 1.010-1.018），这可能与氯之间的转移有关。两个重原子，而在H_3O〜+和Cl〜-浓度低的情况下，氯仿的形成会诱导较小的AKIE（1.005-1.006），这可能与HOCl-铁原卟啉Ⅸ中间体的形成有关。由于土壤中H_3O〜+和Cl〜-的浓度通常处于亚摩尔级，因此在陆地环境中HOCl-铁原卟啉Ⅸ中间体的形成可能会限制速率。考虑到天然存在的氯化物的δ〜（37）Cl值往往在-1和+ 1‰之间，因此天然氯仿的δ〜（37）Cl值应在-5‰和-8‰之间变化。由于工业氯仿的中值δ〜（37）Cl值为-3.0‰，因此本研究表明，氯仿的氯同位素组成可用于区分环境中的工业来源和自然来源。

著录项

  • 来源
    《Environmental Science & Technology》 |2014年第3期|1592-1600|共9页
  • 作者

    Florian Breider; Daniel Hunkeler;

  • 作者单位

    Center for Hydrogeology and Geothermics (CHYN), University of Neuchatel, rue Emile-Argand 11, CH-2000 Neuchatel, Switzerland,Department of Environmental Chemistry and Engineering, Tokyo Institute of Technology, Nagatsuta-cho 4259, Midori-ku, Yokohama, Kanagawa Prefecture, 226-8502 Japan;

    Center for Hydrogeology and Geothermics (CHYN), University of Neuchatel, rue Emile-Argand 11, CH-2000 Neuchatel, Switzerland;

  • 收录信息 美国《科学引文索引》(SCI);美国《工程索引》(EI);美国《生物学医学文摘》(MEDLINE);美国《化学文摘》(CA);
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类
  • 关键词

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号