title: Reactor performance of a 750 m(3) anaerobic digestion plant: varied substrate input conditions impacting methanogenic community.
abstract: A 750 m(3) anaerobic digester was studied over a half year period including a shift from good reactor performance to a reduced one. Various abiotic parameters like volatile fatty acids (VFA) (formic-, acetic-, propionic-, (iso-)butyric-, (iso-)valeric-, lactic acid), total C, total N, NH4 -N, and total proteins, as well as the organic matter content and dry mass were determined. In addition several process parameters such as temperature, pH, retention time and input of substrate and the concentrations of CH4, H2, CO2 and H2S within the reactor were monitored continuously. The present study aimed at the investigation of the abundance of acetogens and total cell numbers and the microbial methanogenic community as derived from PCR-dHPLC analysis in order to put it into context with the determined abiotic parameters. An influence of substrate quantity on the efficiency of the anaerobic digestion process was found as well as a shift from a hydrogenotrophic in times of good reactor performance towards an acetoclastic dominated methanogenic community in times of reduced reactor performance. After the change in substrate conditions it took the methano-archaeal community about 5-6 weeks to be affected but then changes occurred quickly.
authors.affiliation: University of Innsbruck, Institute of Microbiology, Technikerstr. 25, A-6020 Innsbruck, Austria. Electronic address: Andreas.Wagner@uibk.ac.at.
authors.forename: Andreas Otto
authors.initials: AO
authors.lastname: Wagner
authors.affiliation: University of Innsbruck, Institute of Microbiology, Technikerstr. 25, A-6020 Innsbruck, Austria.
authors.forename: Cornelia
authors.initials: C
authors.lastname: Malin
authors.affiliation: University of Innsbruck, Institute of Microbiology, Technikerstr. 25, A-6020 Innsbruck, Austria.
authors.forename: Philipp
authors.initials: P
authors.lastname: Lins
authors.affiliation: Abfallbeseitigungsverband Westtirol, Breite Mure, A-6426 Roppen, Austria.
authors.forename: Gudrun
authors.initials: G
authors.lastname: Gstraunthaler
authors.affiliation: University of Innsbruck, Institute of Microbiology, Technikerstr. 25, A-6020 Innsbruck, Austria.
authors.forename: Paul
authors.initials: P
authors.lastname: Illmer
mesh_terms: D000641:Ammonia / Q000378:metabolism; D000693:Anaerobiosis; D056804:Biofuels; D019149:Bioreactors; D002244:Carbon / Q000378:metabolism; D019641:DNA, Archaeal / Q000235:genetics*; D005232:Fatty Acids, Volatile / Q000378:metabolism; D005285:Fermentation; D005502:Food; D014644:Genetic Variation; D006863:Hydrogen-Ion Concentration; D054892:Metagenome; D008697:Methane / Q000096:biosynthesis*; D017013:Methanobacteriaceae / Q000235:genetics* / Q000378:metabolism; D059013:Microbial Consortia / Q000235:genetics*; D009584:Nitrogen / Q000378:metabolism; D011312:Pressure; D012336:RNA, Ribosomal, 16S / Q000235:genetics*; D060888:Real-Time Polymerase Chain Reaction; D013696:Temperature; D014866:Waste Products
chemical_list: D056804:Biofuels; D019641:DNA, Archaeal; D005232:Fatty Acids, Volatile; D012336:RNA, Ribosomal, 16S; D014866:Waste Products; D002244:Carbon; D000641:Ammonia; D009584:Nitrogen; D008697:Methane
keywords: Anaerobic digestion; Biogas; Methanogen; Substrate