title: Improvement of biogas production by bioaugmentation.
abstract: Biogas production technologies commonly involve the use of natural anaerobic consortia of microbes. The objective of this study was to elucidate the importance of hydrogen in this complex microbial food chain. Novel laboratory biogas reactor prototypes were designed and constructed. The fates of pure hydrogen-producing cultures of Caldicellulosiruptor saccharolyticus and Enterobacter cloacae were followed in time in thermophilic and mesophilic natural biogas-producing communities, respectively. Molecular biological techniques were applied to study the altered ecosystems. A systematic study in 5-litre CSTR digesters revealed that a key fermentation parameter in the maintenance of an altered population balance is the loading rate of total organic solids. Intensification of the biogas production was observed and the results corroborate that the enhanced biogas productivity is associated with the increased abundance of the hydrogen producers. Fermentation parameters did not indicate signs of failure in the biogas production process. Rational construction of more efficient and sustainable biogas-producing microbial consortia is proposed.
authors.affiliation: Department of Biotechnology, University of Szeged, Szeged 6726, Hungary. kovacs.kornel@brc.mta.hu
authors.forename: K L
authors.initials: KL
authors.lastname: Kovács
authors.forename: N
authors.initials: N
authors.lastname: Ács
authors.forename: E
authors.initials: E
authors.lastname: Kovács
authors.forename: R
authors.initials: R
authors.lastname: Wirth
authors.forename: G
authors.initials: G
authors.lastname: Rákhely
authors.forename: Orsolya
authors.initials: O
authors.lastname: Strang
authors.forename: Zsófia
authors.initials: Z
authors.lastname: Herbel
authors.forename: Z
authors.initials: Z
authors.lastname: Bagi
mesh_terms: D000693:Anaerobiosis; D056804:Biofuels; D019149:Bioreactors; D003013:Clostridium / Q000254:growth & development*; D016972:Enterobacter cloacae / Q000254:growth & development*; D006859:Hydrogen / Q000378:metabolism*
chemical_list: D056804:Biofuels; D006859:Hydrogen