Enzymatic Degradation of Organochlorine Insecticide Chlordane by Phlebia brevispora  

作　　者：Pengfei XIAO Ryuichiro KONDO 

机构地区：[1]College of Forestry,Northeast Forestry University [2]Faculty of Agriculture,Kyushu University

出　　处：《Agricultural Biotechnology》2013年第4期53-56,60,共5页农业生物技术（英文版）

基　　金：Supported by the Scientific Research Fund for the Returned Overseas Chinese Scholars,State Education Ministry

摘　　要：[ Objective ] This study aimed to clarify the mechanism of enzymatic degradation of organochlorine insecticide chlordane by the white rot fungus Pldebia brevispora. [ Method ] The degradation characteristics of chlordane were determined by the crude enzyme extracted from P. brevispora strain by pure culture, ultrasonic fragmentation and centrifuge separation. [ Result] About 33.2% and 10.4% of chlordane were degraded respectively by intracellular enzyme and extracellular enzyme within 20 min. At pH 5.0 and 3℃, the crude enzyme showed the greatest degradation activity （49.9%）, with its Michaelis-Mentn＇s constant （Km ） and maximum degradation rate （ Vmax ） of 3.49 and 8.38 ttmol/min, respectively. [ Conclusion] Extracellular enzyme can degrade chlordane through dehydrogenation or dehydrochlorination. Intracellular enzyme plays a major role in chlordane degradation. It can transform chlordane to some hydroxylated metabolites through hydroxylation or substitution of chlorine atom by hydroxyl group.[ Objective ] This study aimed to clarify the mechanism of enzymatic degradation of organochlorine insecticide chlordane by the white rot fungus Pldebia brevispora. [ Method ] The degradation characteristics of chlordane were determined by the crude enzyme extracted from P. brevispora strain by pure culture, ultrasonic fragmentation and centrifuge separation. [ Result] About 33.2% and 10.4% of chlordane were degraded respectively by intracellular enzyme and extracellular enzyme within 20 min. At pH 5.0 and 3℃, the crude enzyme showed the greatest degradation activity （49.9%）, with its Michaelis-Mentn＇s constant （Km ） and maximum degradation rate （ Vmax ） of 3.49 and 8.38 ttmol/min, respectively. [ Conclusion] Extracellular enzyme can degrade chlordane through dehydrogenation or dehydrochlorination. Intracellular enzyme plays a major role in chlordane degradation. It can transform chlordane to some hydroxylated metabolites through hydroxylation or substitution of chlorine atom by hydroxyl group.

关 键 词：CHLORDANE White rot fungus Enzymatic degradation BIOTRANSFORMATION METABOLITE 

分 类 号：X592[环境科学与工程—环境工程]