title: Microbial polychlorinated biphenyl dechlorination in sediments by electrical stimulation: The effect of adding acetate and nonionic surfactant.
abstract: The necessity for developing an efficient and cost-effective in situ bioremediation technology for sediments contaminated with polychlorinated biphenyls (PCBs) has prompted the application of low-voltage electrical fields to anaerobic digestion systems. Here we show that the use of a sediment-based bio-electrochemical reactor (BER) poised at a potential of -0.50V (vs. a standard calomel electrode, SCE) substantially enhanced the reduction of 2,3,4,5-tetrachlorobiphenyl (PCB 61) when acetate was added as a carbon source. The addition of surfactant Tween 80 to the BER further accelerated the PCB 61 transformation. The comparative study of closed- and open-circuit reactors demonstrated the enrichment conditions affecting the bacterial community structure, the dominant dechlorination metabolisms, and thus the extent, the rate and the products of the reduction of PCBs. The dominant bacterial dechlorinators detected in the BERs in the presence of acetate and Tween 80 are Dehalogenimonas, Dehalobacter, Sulfuricurvum, Dechloromonas and Geobacter, which should be responsible for PCB dechlorination. This study improves understanding of the key factors influencing dechlorination activity in sediment-based BERs polarized at a low potential, as well as the metabolic mechanisms dominating in the PCB dechlorination process.
authors.affiliation: 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.
authors.forename: Hui
authors.initials: H
authors.lastname: Yu
authors.affiliation: 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.
authors.forename: Hui
authors.initials: H
authors.lastname: Wan
authors.affiliation: 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; Guangdong Provincial Engineering and Technology Research Center for Environmental Risk Prevention and Emergency Disposal, South China University of Technology, Guangzhou 510006, PR China. Electronic address: chfeng@scut.edu.cn.
authors.forename: Chunhua
authors.initials: C
authors.lastname: Feng
authors.affiliation: 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.
authors.forename: Xiaoyun
authors.initials: X
authors.lastname: Yi
authors.affiliation: 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.
authors.forename: Xiaoping
authors.initials: X
authors.lastname: Liu
authors.affiliation: 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.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Ren
authors.affiliation: 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.
authors.forename: Chaohai
authors.initials: C
authors.lastname: Wei
mesh_terms: D000085:Acetates / Q000737:chemistry*; D001673:Biodegradation, Environmental; D019149:Bioreactors; D002713:Chlorine / Q000737:chemistry*; D004560:Electricity; D019015:Geologic Sediments / Q000737:chemistry*; D011078:Polychlorinated Biphenyls / Q000737:chemistry*; D013501:Surface-Active Agents / Q000737:chemistry*
chemical_list: D000085:Acetates; D013501:Surface-Active Agents; D002713:Chlorine; D011078:Polychlorinated Biphenyls
keywords: Bio-electrochemical technology; Biocathode; Dechlorinating bacteria; Electron donor; Sediment bioremediation; Tween 80