title: Suppression of methanogenesis in cellulose-fed microbial fuel cells in relation to performance, metabolite formation, and microbial population.
abstract: The objective of this work was to evaluate methanogenesis in relation to the changes in performance and microbial diversity of cellulose-fed microbial fuel cells (MFCs). Replicate MFCs were inoculated with a ruminal microbial consortium and operated under 20 (R20Ω) or 100 Ω (R100Ω) external resistances. During the first week of operation, 0.31 and 0.44 mmol l(-1) of methane were produced in the R20Ω and R100Ω MFCs, respectively. Methanogenesis was, however, suppressed to undetectable levels within 90 days of operation, accompanied with increased current production and improved coulombic efficiency. Suppressed methanogenesis coincided with changes in the concentrations of short chain fatty acids and a decrease in the microbial diversity. The results demonstrated that methanogenesis was active during the early stage of cellulose-fed MFCs but this activity declined over prolonged operation.
authors.affiliation: Department of Food, Agricultural and Biological Engineering, Ohio State University, 590 Woody Hayes Drive, Columbus, OH 43210, USA.
authors.forename: Hamid
authors.initials: H
authors.lastname: Rismani-Yazdi
authors.forename: Sarah M
authors.initials: SM
authors.lastname: Carver
authors.forename: Ann D
authors.initials: AD
authors.lastname: Christy
authors.forename: Zhongtang
authors.initials: Z
authors.lastname: Yu
authors.forename: Kyle
authors.initials: K
authors.lastname: Bibby
authors.forename: Jordan
authors.initials: J
authors.lastname: Peccia
authors.forename: Olli H
authors.initials: OH
authors.lastname: Tuovinen
mesh_terms: D044822:Biodiversity; D001674:Bioelectric Energy Sources / Q000382:microbiology*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D008697:Methane / Q000378:metabolism*; D059013:Microbial Consortia / Q000502:physiology*
chemical_list: D008697:Methane