2,2',4,4'-四溴联苯醚高效好氧降解菌的鉴定及其降解路径  

Identification of an aerobic strain efficiently degrading 2, 2', 4, 4'-tetrabromodiphenyl ether and its biodegradation pathway

作　　者：黄婷 段星春 陶雪琴[3] 谢莹莹 党志 卢桂宁[1,5] 

机构地区：[1]华南理工大学环境与能源学院,广州510006 [2]广州开发区供水管理中心,广州510663 [3]仲恺农业工程学院环境科学与工程学院,广州510225 [4]工业聚集区污染控制与生态修复教育部重点实验室,广州510006 [5]广东省环境风险防控与应急处置工程技术研究中心,广州510006

出　　处：《环境科学学报》2017年第12期4705-4714,共10页Acta Scientiae Circumstantiae

基　　金：国家自然科学基金(No.41573091);广东省自然科学杰出青年基金(No.2015A030306005);广东省特支计划科技创新青年拔尖人才项目(No.2015TQ01Z233)~~

摘　　要：2,2',4,4'-四溴联苯醚(BDE-47)是环境和生物体中普遍检出且生物毒性较大的一种多溴联苯醚同系物.本研究从广东省贵屿镇电子垃圾拆解厂周边采集的农田土壤中分离出一株BDE-47的高效好氧降解菌GYP1,考察了其对BDE-47的降解性能、降解路径及不同的环境因素对菌株降解BDE-47的影响.根据菌株形态特征、16S r DNA基因序列及系统发育树分析,将该菌鉴定为伯克霍尔德菌(Burkholderia cepacia).结果表明,菌株GYP1在好氧条件下能够利用BDE-47为唯一碳源生长,在BDE-47初始质量浓度为1 mg·L^(-1)、温度为30℃、摇床转速为150r·min^(-1)的条件下避光培养4 d,该菌株对BDE-47的降解率可达到82.4%.菌株GYP1在15~35℃和p H=4.0~7.0的环境条件范围内对BDE-47均能保持良好的降解性能,但外加蔗糖、酵母粉、联苯醚等碳源会明显抑制其对BDE-47的降解.在菌株GYP1对BDE-47的降解过程中检测到6-OH-BDE-47、5-OH-BDE-47、4'-OH-BDE-17、2'-OH-BDE-3这4种羟基多溴联苯醚及2,4-二溴苯酚,证明菌株GYP1对BDE-47的好氧降解机理主要是羟基化过程.2,2＇,4,4＇-Tetrabromodiphenyl ether（BDE-47）is one of toxic polybrominated diphenyl ethers（PBDEs）which was frequently detected in the environment and organisms.In the current study,a highly effective aerobic strain（GYP1）for degrading BDE-47 was isolated from the paddy field soil of the electronic-waste recycling area in Guiyu Town,Guangdong Province.The biodegradation pathway of BDE-47 and effects of different environmental factors on its biodegradation rates were investigated.The strain was identified as Burkholderia cepacia based on its morphology,16S r DNA sequence,and related phylogenetic tree.Results show that strain GYP1 could utilize BDE-47 as the sole carbon source under aerobic conditions.The biodegradation rate of BDE-47 of 82.4%was achieved in 4 d,when the initial concentration of BDE-47 was 1 mg·L^（-1）and incubated in 30℃at 150 r·min^（-1）in a shaker.Strain GYP1 could also maintain relatively high degrading efficiency for BDE-47 under the temperature range of 15~35℃and p H range of 4.0~7.0.However,the additions of sucrose,yeast extract,diphenyl ether as co-substrates could significantly decrease the biodegradation rate of BDE-47 by strain GYP1.2,4-Dibromophenol（2,4-DBP）and four hydroxylated PBDEs,including 6-OH-BDE-47,5-OH-BDE-47,4＇-OH-BDE-17,2＇-OH-BDE-3,were detected in the biodegradation process of BDE-47,which demonstrated the aerobic degradation of BDE-47 by strain GYP1 was accompanied by hydroxylation.

关 键 词：2 2' 4 4'-四溴联苯醚 好氧条件 伯克霍尔德菌 微生物降解 降解路径 

分 类 号：X172[环境科学与工程—环境科学]