Biodegradation of decabromodiphenyl ether (BDE-209) by bacterial mixed cultures in a soil/water system
Biodegradation of decabromodiphenyl ether (BDE-209) by bacterial mixed cultures in a soil/water system
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DOI：
10.1016/j.ibiod.2013.05.006
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发表时间：
2013-11-01
影响因子：
4.8
通讯作者：
Lin, Ching-Hsing
中科院分区：
文献类型：
--
作者：
Chou, Hsi-Ling;Chang, Yi-Tang;Lin, Ching-Hsing
十溴二苯醚（DBDE）是一种溴化阻燃剂，通常用于许多商业产品。在土壤/水系统中吸附十溴二苯醚可导致生态系统中严重的生物累积，并对人类健康构成威胁。目前对DBDE的好氧生物降解知之甚少，也没有考虑紫外光辐射对DBDE生物降解的影响。本研究首次从台湾地区受DBDE污染的土壤/水系统中分离出DBDE生物降解需氧混合细菌培养物。采用粘土/水体系，研究了在365 nm UVA照射下，DBDE作为唯一碳源的好氧生物降解行为。在紫外线照射下，DBDE降解的速率常数为0.0121 - 0.0134天（-1），明显高于在完全黑暗中获得的0.0092-0.0102天（-1）的数值。需氧代谢产物：通过GC-MS分析，确定了2 '，3'-二羟基-4-溴二苯醚和2 '，3'-二羟基二苯醚的结构。脱溴产物包括12种多溴二苯醚同系物（三溴二苯醚至六溴二苯醚），其浓度范围为34.28至83.80毫克/升。确定了能够降解多溴二苯醚并进行硝化/反硝化的特定细菌。目前的研究结果表明，可以开发一种新的光解和生物降解相结合的系统，以在未来进行DBDE补救。(C)2013爱思唯尔有限公司保留所有权利。
Decabromodiphenyl ether (DBDE) is a brominated flame retardant that is commonly used in many commercial products. Sorption of DBDE within a soil/water system can result in serious bioaccumulation within the ecological system and be a threat to human health. Little is known about aerobic DBDE biodegradation, and the influence of the UV light radiation on DBDE biodegradation has not been considered. This study, for the first time, isolates DBDE biodegrading aerobic mixed bacterial cultures from DBDE-contaminated soil/water systems in Taiwan. The aerobic biodegradation of DBDE as a sole carbon source in the presence of 365 nm UVA irradiation over 10 months was investigated using a clay/water system. The rate constants for DBDE degradation gave values ranging from 0.0121 to 0.0134 day(-1) in the presence of UV irradiation, which were significantly higher than the 0.0092-0.0102 day(-1) values obtained in complete darkness. The aerobic metabolites: 2',3'-dihydroxy-4-bromodiphenyl ether and 2',3'-dihydroxy-diphenyl ether were identified by GC-MS. Debromination was ascribed to UV irradiation and biodegradation by facultative aerobic bacteria in the micro-anaerobic environment of the clay/water system. The products of debromination included 12 PBDE congeners (tri- to hexa-BDEs) and their concentrations ranged from 34.28 to 83.80 mg l(-1). Specific bacteria capable of degrading PBDEs and carrying out nitrification/denitrification were identified. The present findings suggest that systems using a novel combination of photolysis and biodegradation could be developed to carry out DBDE remediation in the future. (C) 2013 Elsevier Ltd. All rights reserved.