The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, School of Environment and Energy, South China University of Technology, Guangzhou 510006, PR China.
The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, School of Environment and Energy, South China University of Technology, Guangzhou 510006, PR China.
Environ Pollut. 2016 Apr;211:81-9. doi: 10.1016/j.envpol.2015.12.039. Epub 2015 Dec 30.
The application of a low-voltage electric field as an electron donor or acceptor to promote the bioremediation of chlorinated organic compounds represents a promising technology meeting the demand of developing an efficient and cost-effective strategy for in situ treatment of PCB-contaminated sediments. Here, we reported that bioanode stimulation with an anodic potential markedly enhanced dechlorination of 2,3,4,5-tetrachlorobiphenyl (PCB 61) contained in the sediment at an electronic waste recycling site of Qingyuan, Guangdong, China. The 110-day incubation of the bioanode with a potential poised at 0.2 V relative to saturated calomel electrode enabled 58% transformation of the total PCB 61 at the initial concentration of 100 μmol kg(-1), while only 23% was reduced in the open-circuit reference experiment. The introduction of acetate to the bioelectrochemical reactor (BER) further improved PCB 61 transformation to 82%. Analysis of the bacterial composition showed significant community shifts in response to variations in treatment. At phylum level, the bioanode stimulation resulted in substantially increased abundance of Actinobacteria, Bacteroidetes, and Chloroflexi either capable of PCB dechlorination, or detected in the PCB-contaminated environment. At genus level, the BER contained two types of microorganisms: electrochemically active bacteria (EAB) represented by Geobacter, Ignavibacterium, and Dysgonomonas, and dechlorinating bacteria including Hydrogenophaga, Alcanivorax, Sedimentibacter, Dehalogenimonas, Comamonas and Vibrio. These results suggest that the presence of EAB can promote the population of dechlorinating bacteria which are responsible for PCB 61 transformation.
应用低压电场作为电子供体或受体来促进氯化有机化合物的生物修复，代表了一种有前途的技术，满足了开发高效、经济的 PCB 污染沉积物原位处理策略的需求。在这里，我们报告了生物阳极刺激用阳极电势显著增强了在中国广东省清远市电子废物回收场的沉积物中 2,3,4,5-四氯联苯（PCB61）的脱氯。在 0.2 V 相对于饱和甘汞电极的电势下，生物阳极的 110 天孵育使初始浓度为 100 μmol kg(-1)的总 PCB61 的转化率达到 58%，而在开路参考实验中仅还原了 23%。向生物电化学反应器（BER）中引入乙酸盐进一步将 PCB61 的转化提高到 82%。细菌组成的分析表明，处理的变化导致了明显的群落变化。在门水平上，生物阳极刺激导致具有 PCB 脱氯能力或在 PCB 污染环境中检测到的放线菌门、拟杆菌门和绿屈挠菌门的丰度显著增加。在属水平上，BER 含有两种类型的微生物：以 Geobacter、Ignavibacterium 和 Dysgonomonas 为代表的电化学活性细菌（EAB），以及脱氯细菌，包括 Hydrogenophaga、Alcanivorax、Sedimentibacter、Dehalogenimonas、Comamonas 和 Vibrio。这些结果表明，EAB 的存在可以促进负责 PCB61 转化的脱氯细菌的种群增加。
