title: The potential of producing heterotrophic bacteria biomass on aquaculture waste.
abstract: The effluent from the drumfilter of a recirculation aquaculture system was used as substrate to produce heterotrophic bacteria in suspended growth reactors. The effects of organic carbon supplementation (0, 3, 6, 8 g/l sodium acetate) and of hydraulic retention times (11-1h) on bacteria biomass production and nutrient conversion were investigated. Bacteria production, expressed as volatile suspended solids (VSS), was enhanced by organic carbon supplementation, resulting in a production of 55-125 g VSS/kg fish feed (0.2-0.5 g VSS/g carbon). Maximum observed crude protein production was approximately 100 g protein/kg fish feed. The metabolic maintenance costs were 0.08 Cmol/Cmol h, and the maximum growth rate was 0.25-0.5 h(-1). Ninety percent of the inorganic nitrogenous and 80% of ortho-phosphate were converted. Producing bacteria on the drumfilter effluent results in additional protein retention and lowers overall nutrient discharge from recirculation aquaculture systems.
authors.affiliation: Aquaculture and Fisheries Group, Wageningen University, P.O. Box 338, 6700 AH Wageningen, The Netherlands.
authors.forename: Oliver
authors.initials: O
authors.lastname: Schneider
authors.forename: Vasiliki
authors.initials: V
authors.lastname: Sereti
authors.forename: Marcel A M
authors.initials: MA
authors.lastname: Machiels
authors.forename: Ep H
authors.initials: EH
authors.lastname: Eding
authors.forename: Johan A J
authors.initials: JA
authors.lastname: Verreth
mesh_terms: D000818:Animals; D017756:Aquaculture / Q000295:instrumentation / Q000379:methods*; D001419:Bacteria / Q000378:metabolism*; D018533:Biomass; D019149:Bioreactors / Q000382:microbiology*; D005399:Fishes; D052836:Heterotrophic Processes; D013379:Substrate Specificity; D014865:Waste Disposal, Fluid / Q000295:instrumentation / Q000379:methods*; D014873:Water Pollutants / Q000378:metabolism*
chemical_list: D014873:Water Pollutants