title: Enrichment of microbial community generating electricity using a fuel-cell-type electrochemical cell.
abstract: A fuel cell was used to enrich a microbial consortium generating electricity, using organic wastewater as the fuel. Within 30 days of enrichment the maximum current of 0.2 mA was generated with a resistance of 1 kOhms. Current generation was coupled to a fall in chemical oxygen demand from over 1,700 mg l(-1) down to 50 mg l(-1). Denaturing gradient gel electrophoresis showed a different microbial population in the enriched electrode from that in the sludge used as the inoculum. Electron microscopic observation showed a biofilm on the electrode surface and microbial clumps. Nanobacteria-like particles were present on the biofilm surface. Metabolic inhibitors and electron acceptors inhibited the current generation. 16S ribosomal RNA gene analysis showed a diverse bacterial population in the enrichment culture. These findings demonstrate that an electricity-generating microbial consortium can be enriched using a fuel cell and that the electrochemical activity is a form of anaerobic electron transfer.
authors.affiliation: Water Environment & Remediation Research Center, Korea Institute of Science and Technology, 39-1 Hawolgok, Sungpook, 136-791, Seoul, Korea. bhkim@kist.re.kr
authors.forename: B H
authors.initials: BH
authors.lastname: Kim
authors.forename: H S
authors.initials: HS
authors.lastname: Park
authors.forename: H J
authors.initials: HJ
authors.lastname: Kim
authors.forename: G T
authors.initials: GT
authors.lastname: Kim
authors.forename: I S
authors.initials: IS
authors.lastname: Chang
authors.forename: J
authors.initials: J
authors.lastname: Lee
authors.forename: N T
authors.initials: NT
authors.lastname: Phung
mesh_terms: D001419:Bacteria / Q000145:classification* / Q000254:growth & development* / Q000378:metabolism / Q000648:ultrastructure; D001674:Bioelectric Energy Sources; D018441:Biofilms / Q000254:growth & development; D002384:Catalysis; D004269:DNA, Bacterial / Q000032:analysis / Q000737:chemistry / Q000302:isolation & purification; D004275:DNA, Ribosomal / Q000032:analysis / Q000737:chemistry / Q000302:isolation & purification; D004560:Electricity; D004563:Electrochemistry; D004566:Electrodes; D004579:Electron Transport / Q000502:physiology; D004591:Electrophoresis, Polyacrylamide Gel; D004783:Environmental Microbiology; D007220:Industrial Waste; D008969:Molecular Sequence Data; D009930:Organic Chemicals / Q000378:metabolism*; D010084:Oxidation-Reduction; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D012722:Sewage / Q000382:microbiology*; D014865:Waste Disposal, Fluid / Q000379:methods; D014871:Water Microbiology
chemical_list: D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D007220:Industrial Waste; D009930:Organic Chemicals; D012336:RNA, Ribosomal, 16S; D012722:Sewage