厌氧条件下2,2＇,4,4＇-四溴联苯醚的微生物降解  

Microbial Degradation of 2,2′,4,4′-Tetrabrominated Diphenyl Ether Under Anaerobic Condition

作　　者：卢晓霞[1] 陈超琪[1] 张姝[1] 欧阳[1] 尹力[1] 吴蔚[1] 

机构地区：[1]北京大学城市与环境学院,地表过程分析与模拟教育部重点实验室,北京100871

出　　处：《环境科学》2012年第3期1000-1007,共8页Environmental Science

基　　金：国家自然科学基金项目(40871214,40830746,41030529);高等学校博士学科点专项科研基金项目(20070001047)

摘　　要：多溴联苯醚是环境中的新兴污染物,其中2,2',4,4'-四溴联苯醚(BDE-47)在环境(尤其是水环境)中普遍存在且生物毒性很高.以BDE-47为对象,研究了6组含脱卤球菌的培养液对BDE-47的降解,目的是了解厌氧条件下BDE-47的微生物降解及其动力学.采用100 mL血清瓶作为厌氧反应器,对厌氧微生物进行培养.对每组菌作两种处理,一是仅加入BDE-47作为能源(设计终浓度为200μg.L-1),另一是同时加入BDE-47和三氯乙烯(TCE)作为能源(设计终浓度分别为200μg.L-1和13mg.L-1).经过3个月的实验,两组含脱卤球菌的培养液(6M6B和T2)均能明显降解BDE-47,生成BDE-17、BDE-4及少量的DE,TCE的存在一定程度上减弱了6M6B和T2菌对BDE-47的降解.采用PCR-DGGE法对不同培养菌液的群落结构进行比较,发现醋酸杆菌属与BDE-47的降解关联较大.在3种不同初始浓度(50、250和500μg.L-1)条件下,BDE-47的降解速率分别为0.003 3、0.001 4和0.001 0 d-1.本研究表明,厌氧条件下BDE-47在细菌的作用下可发生还原降解,生成BDE-17和BDE-4.醋酸杆菌属可能在BDE-47的降解中起较大作用.高浓度的BDE-47在一定程度上会抑制降解菌的活性.Polybrominated diphenyl ethers are emerging contaminants in the environment,among which 2,2′4,4′-tetrabrominated diphenyl ether（BDE-47） is one of the most frequently detected and the most toxic to organisms.Using BDE-47 as the object,this study investigated the degradation of BDE-47 by six enriched cultures containing Dehalococcoides species.The purpose is to understand the microbial degradation of BDE-47 under anaerobic condition and its kinetics.Serum bottles of 100 mL were used to construct the microcosms and enrich the anaerobic microorganisms.For each culture,two treatments were performed.One used BDE-47 as the only energy source with the designed concentration of 200 μg·L-1,and the other used both BDE-47 and trichloroethene（TCE） as the energy source with the designed concentrations being 200 μg·L-1 and 13 mg·L-1,respectively.After three months of experiment,two enriched cultures（6M6B and T2） could obviously degrade BDE-47,producing BDE-17 and BDE-4（and small amount of DE）.The presence of TCE inhibited the degradation of BDE-47 by 6M6B and T2 cultures to a certain degree.The PCR-DGGE assay was performed to compare the microbial community structure of various enrichments and it was found that Acetobacterium sp.had good correlation with the degradation of BDE-47.Under three different initial BDE-47 concentrations（50 μg·L-1,250 μg·L-1 and 500 μg·L-1）,the degradation rates of BDE-47 were 0.003 3,0.001 4 and 0.001 0 d-1,respectively.This study demonstrated that BDE-47 could be reductively degraded by bacteria under anaerobic condition,producing BDE-17 and BDE-4.Acetobacterium sp.might play an important role in the degradation of BDE-47.High concentration of BDE-47 might inhibit the activity of the BDE-47 degrading bacteria to a certain degree.

关 键 词：2 2' 4 4'-四溴联苯醚 微生物降解 细菌培养液 群落结构 动力学 

分 类 号：X172[环境科学与工程—环境科学]