Microbial degradation of 4-monobrominated diphenyl ether in an aerobic sludge and the DGGE analysis of diversity
Microbial degradation of 4-monobrominated diphenyl ether in an aerobic sludge and the DGGE analysis of diversity
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DOI：
10.1080/03601231003799945
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发表时间：
2010-01-01
影响因子：
2
通讯作者：
Shih, Yang-Hsin
中科院分区：
文献类型：
--
作者：
Chen, Chun-Yao;Wang, Chun-Kang;Shih, Yang-Hsin
多溴联苯醚（PBDEs）作为阻燃剂被广泛应用于塑料和电子产品的聚合物中。由于多溴二苯醚在环境中的广泛分布、对人体的潜在毒性和生物累积性，多溴二苯醚已引起公众的关注。在这项研究中，我们研究了4-单溴二苯醚（4-BDE）在好氧污泥中的降解，作为PBDE生物降解的模型。4-BDE在好氧污泥中降解。与甲苯或二苯醚的共代谢促进了4-BDE的生物降解动力学和效率。在促进4-溴二苯醚降解方面，二苯醚作为辅助碳源的表现似乎略好于甲苯。在实验过程中，我们确定了二苯醚的气相色谱/质谱（GC/MS），这表明厌氧脱溴发生。用变性梯度凝胶电泳监测细菌群落组成。富含4-BDE降解好氧污泥样品的片段可能属于一种新的厌氧梭菌目物种，与所有已知的脱溴微生物都有较远的关系。这表明，4-溴二苯醚的生物降解可在明显需氧环境中的厌氧微生态位中发生，由一种以前未知的细菌物种进行。这些研究结果可以提供更好的理解溴化二苯醚的生物降解，并可以促进多溴联苯醚在环境中的归宿预测。
Polybrominated diphenyl ethers (PBDEs) were applied as flame retardant additives in polymers for many plastic and electronic products. Due to their ubiquitous distribution in the environment, potential toxicity to human and tendency for bioaccumulation, PBDEs have raised public safety concern. In this study we examined the degradation of 4-monobrominated diphenyl ether (4-BDE) in aerobic sludge, as a model for PBDE biodegradation. Degradation of 4-BDE was observed in aerobic sludge. Co-metabolism with toluene or diphenyl ether facilitated 4-BDE biodegradation in terms of kinetics and efficiency. Diphenyl ether seems to perform slightly better as an auxiliary carbon source than toluene in facilitating 4-BDE degradation. During the experiment we identified diphenyl ether by gas chromatography/mass spectrometry(GC/MS), which indicates that an anaerobic debromination has occurred. Bacterial community composition was monitored with denaturing gradient gel electrophoresis. The fragments enriched in 4-BDE-degrading aerobic sludge samples belong to presumably a novel anaerobic Clostridiales species distantly related to all known debrominating microbes. This suggests that 4-BDE biodegradation can occur in anaerobic micro-niche in an apparently aerobic environment, by a previously unknown bacterial species. These findings can provide better understandings of biodegradation of brominated diphenyl ethers and can facilitate the prediction of the fate of PBDEs in the environment.