title: Changes of the microbial population structure in an overloaded fed-batch biogas reactor digesting maize silage.
abstract: Two parallel, stable operating biogas reactors were fed with increasing amounts of maize silage to monitor microbial community changes caused by overloading. Changes of microorganisms diversity revealed by SSCP (single strand conformation polymorphism) indicating an acidification before and during the pH-value decrease. The earliest indicator was the appearance of a Methanosarcina thermophila-related species. Diversity of dominant fermenting bacteria within Bacteroidetes, Firmicutes and other Bacteria decreased upon overloading. Some species became dominant directly before and during acidification and thus could be suitable as possible indicator organisms for detection of futurity acidification. Those bacteria were related to Prolixibacter bellariivorans and Streptococcus infantarius subsp. infantarius. An early detection of community shifts will allow better feeding management for optimal biogas production.
authors.affiliation: Institute of Applied Microbiology, Justus-Liebig University, Gießen, Germany.
authors.forename: Kristina
authors.initials: K
authors.lastname: Kampmann
authors.affiliation: Institute of Applied Microbiology, Justus-Liebig University, Gießen, Germany. Electronic address: stefan.ratering@umwelt.uni-giessen.de.
authors.forename: Stefan
authors.initials: S
authors.lastname: Ratering
authors.affiliation: Institute of Applied Microbiology, Justus-Liebig University, Gießen, Germany.
authors.forename: Rita
authors.initials: R
authors.lastname: Geißler-Plaum
authors.affiliation: Landesbetrieb Hessisches Landeslabor (LHL), Standort Bad Hersfeld, Bad Hersfeld, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Schmidt
authors.affiliation: Landesbetrieb Hessisches Landeslabor (LHL), Standort Bad Hersfeld, Bad Hersfeld, Germany.
authors.forename: Walter
authors.initials: W
authors.lastname: Zerr
authors.affiliation: Institute of Applied Microbiology, Justus-Liebig University, Gießen, Germany.
authors.forename: Sylvia
authors.initials: S
authors.lastname: Schnell
mesh_terms: D000085:Acetates / Q000032:analysis; D001419:Bacteria / Q000254:growth & development*; D061249:Batch Cell Culture Techniques / Q000295:instrumentation*; D056804:Biofuels / Q000382:microbiology*; D019149:Bioreactors / Q000382:microbiology*; D006863:Hydrogen-Ion Concentration; D008697:Methane / Q000096:biosynthesis; D008969:Molecular Sequence Data; D010802:Phylogeny; D018807:Polymorphism, Single-Stranded Conformational; D011422:Propionates / Q000032:analysis; D012037:Refuse Disposal / Q000295:instrumentation*; D012820:Silage / Q000382:microbiology*; D003313:Zea mays / Q000737:chemistry*
chemical_list: D000085:Acetates; D056804:Biofuels; D011422:Propionates; D008697:Methane
keywords: Acidification; Biogas; Digester overload; Indicator microorganisms; Microbial community structure