title: Physiological and kinetic characterization of a suspended cell anammox culture.
abstract: Anammox related technologies are currently widely applied for nitrogen removal from sewage sludge digester rejection water. Nevertheless, many aspects of the anammox process like the kinetic characteristics and the reaction stoichiometry are still subject of debate. Parameter values reported in literature are often hampered by mass transfer limitation or by the presence of a significant side population. In this study a membrane bioreactor (MBR) based method for growing a highly enriched anammox microbial community is described. The almost pure free-cells suspension of highly active anammox bacteria was used for detailed kinetic and stoichiometric analysis of the anammox process. The anammox culture enriched during this study had a biomass specific maximum growth rate of 0.21 d(-)(1) which is higher than ever reported before in literature. Using an experimental methodology based on imposing dynamic process conditions combined with process modeling and parameter estimation, the intrinsic nitrite half saturation constant was identified to be as low as 35 μg-N L(-)(1). This was confirmed to be an accurate estimation in the pH range of 6.8-7.5.
authors.affiliation: Department of Biotechnology, Delft University of Technology, Julianalaan 67, Delft 2628 BC, the Netherlands. Electronic address: tlotti@dicea.unifi.it.
authors.forename: T
authors.initials: T
authors.lastname: Lotti
authors.affiliation: Department of Biotechnology, Delft University of Technology, Julianalaan 67, Delft 2628 BC, the Netherlands.
authors.forename: R
authors.initials: R
authors.lastname: Kleerebezem
authors.affiliation: Department of Civil and Environmental Engineering, University of Florence, Via di S.Marta 3, 50139 Florence, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Lubello
authors.affiliation: Department of Biotechnology, Delft University of Technology, Julianalaan 67, Delft 2628 BC, the Netherlands. Electronic address: M.C.M.vanLoosdrecht@tudelft.nl.
authors.forename: M C M
authors.initials: MCM
authors.lastname: van Loosdrecht
mesh_terms: D000641:Ammonia / Q000378:metabolism*; D000693:Anaerobiosis; D001419:Bacteria / Q000235:genetics / Q000254:growth & development* / Q000302:isolation & purification; D019149:Bioreactors / Q000382:microbiology*; D004269:DNA, Bacterial / Q000235:genetics; D007700:Kinetics; D008969:Molecular Sequence Data; D009584:Nitrogen / Q000378:metabolism; D010084:Oxidation-Reduction; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D012722:Sewage / Q000382:microbiology*; D014865:Waste Disposal, Fluid
chemical_list: D004269:DNA, Bacterial; D012336:RNA, Ribosomal, 16S; D012722:Sewage; D000641:Ammonia; D009584:Nitrogen
keywords: Anammox; Free-cells suspension; Growth rate; Nitrite half saturation constant; Nitrogen source; Stoichiometry