摘要
氯苯类生物降解机制可分为三类 :氧化脱氯、还原脱氯和共代谢。氯苯类的氧化脱氯机制基本遵循一个相似的降解途径 ,即首先在双氧化酶攻击下形成二醇 ,此二醇脱氢形成氯代邻二酚。邻二酚开环产物是相应的氯化粘康酸 ,脱氯过程发生在此粘康酸内酯化过程中和内酯开环后 ;还原脱氯需要多种微生物共同参与 ,脱氯途径很不一样 ,这与不同微生物种群和不同的环境条件有关 ;共代谢作用降低了氯苯类化合物的生物毒性 ,使其更易为别的微生物同化。
Chlorinated Benzenes (CBs) are widely used industrial chemicals. In aerobic and anaerobic conditions, biodegradations of CBs by microorganisms were reviewed. The machanisms of biodegradation of CBs can be categorized as oxidative dechlorination, reductive dechlorination and cometablism. In oxidative dechlorinationn, CBs were biodegraded via a similar pathway. The initial oxidative attack by CBs dioxygenase is proceed via the chlorinated dihydrodiol, which should yield corresponding chlorocatechol upon enzymatic dehydrogenation and rearomatization. It follows a modified ortho cleavage pathway, yielding chloromuconic acid. The eliminating of chloride in the form of HCl occurs during the course of lactonization of the muconic acid, and after the cleavage of the lacton to form corresponding maleylacetate. In reductive dechlorination, the biodegradation pathways vary with different microbial consortium and environmental conditions. Cometablism reduces the toxicity of CBs, thus makes them more readily degraded by other microorganisms.
出处
《环境污染治理技术与设备》
CSCD
2000年第4期1-12,共12页
Techniques and Equipment for Environmental Pollution Control
基金
国家自然科学基金!资助项目 2 96770 2 7
环境模拟与污染控制国家重点联合实验室开放基金
关键词
生物降解
氯苯类化合物
脱氯
共代谢
废水处理
chlorobenzenes
biodegradation
oxidative dechlorination
reductive dechlorination
cometablism.
