title: [Microbial reduction of Cu2+ mediated by electroactive biofilms].
abstract: The formation, electron transfer mechanism and environmental effect of electrochemically active biofilms (EABs) have become a hot research topic in environmental science. In this study, bacteria were enriched on a carbon felt to form an EAB under controlled potential conditions. The electrochemical properties of the EAB were evaluated with electrochemical methods. The process of copper reduction and transformation mediated by the EAB was revealed. Analytical techniques such as scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS) were used to examine the morphology, content and state of copper in the biofilm. The results showed that the EAB could utilize acetate as electron donor to produce electrons and Cu2+ was reduced to Cu or Cu+. Laser scanning confocal microscope (LSCM) was employed to probe the toxic effects of Cu2+ on the EAB. Copper toxicity on the microbes was reduced in the presence of acetate because of the reduction transformation of Cu2+ to less toxic Cu or Cu+. The results from this study are expected to be instructive for using EABs to stabilize and recover copper from copper-contaminated environments.
authors.forename: Yi
authors.initials: Y
authors.lastname: Liu
authors.forename: Shun-Gui
authors.initials: SG
authors.lastname: Zhou
authors.forename: Yong
authors.initials: Y
authors.lastname: Yuan
authors.forename: Zhi
authors.initials: Z
authors.lastname: Liu
mesh_terms: D001419:Bacteria / Q000378:metabolism*; D001673:Biodegradation, Environmental; D018441:Biofilms; D018914:Cells, Immobilized; D003300:Copper / Q000737:chemistry*; D055664:Electrochemical Techniques; D004579:Electron Transport; D008855:Microscopy, Electron, Scanning; D010084:Oxidation-Reduction; D056951:Photoelectron Spectroscopy; D013052:Spectrometry, X-Ray Emission
chemical_list: D003300:Copper