title: Garden compost inoculum leads to microbial bioanodes with potential-independent characteristics.
abstract: Garden compost leachate was used to form microbial bioanodes under polarization at -0.4, -0.2 and +0.1 V/SCE. Current densities were 6.3 and 8.9 A m(-2) on average at -0.4 and +0.1 V/SCE respectively, with acetate 10 mM. The catalytic cyclic voltammetry (CV) showed similar electrochemical characteristics for all bioanodes and indicated that the lower currents recorded at -0.4V/SCE were due to the slower interfacial electron transfer rate at this potential, consistently with conventional electrochemical kinetics. RNA- and DNA-based DGGE evidenced that the three dominant bacterial groups Geobacter, Anaerophaga and Pelobacter were identical for all bioanodes and did not depend on the polarization potential. Only non-turnover CVs showed differences in the redox equipment of the biofilms, the highest potential promoting multiple electron transfer pathways. This first description of a potential-independent electroactive microbial community opens up promising prospects for the design of stable bioanodes for microbial fuel cells.
authors.affiliation: Laboratoire de Génie Chimique (LGC), CNRS, Université de Toulouse (INPT), 4 allée Emile Monso, BP 84234, 31432 Toulouse, France.
authors.forename: Bibiana
authors.initials: B
authors.lastname: Cercado
authors.forename: Nathalie
authors.initials: N
authors.lastname: Byrne
authors.forename: Marie
authors.initials: M
authors.lastname: Bertrand
authors.forename: Diana
authors.initials: D
authors.lastname: Pocaznoi
authors.forename: Mickaël
authors.initials: M
authors.lastname: Rimboud
authors.forename: Wafa
authors.initials: W
authors.lastname: Achouak
authors.forename: Alain
authors.initials: A
authors.lastname: Bergel
mesh_terms: D000085:Acetates / Q000032:analysis; D001419:Bacteria / Q000235:genetics / Q000378:metabolism*; D001674:Bioelectric Energy Sources / Q000382:microbiology*; D018441:Biofilms / Q000254:growth & development; D058645:Denaturing Gradient Gel Electrophoresis; D004560:Electricity; D055664:Electrochemical Techniques; D004566:Electrodes / Q000382:microbiology; D051639:Gardening; D005798:Genes, Bacterial / Q000235:genetics; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012987:Soil
chemical_list: D000085:Acetates; D012336:RNA, Ribosomal, 16S; D012987:Soil