title: Tracking and quantification of nitrifying bacteria in biofilm and mixed liquor of a partial nitrification MBBR pilot plant using fluorescence in situ hybridization.
abstract: A moving bead biofilm reactor (MBBR) pilot plant was implemented as a partial nitrification process for pre-treatment of ammonium-rich liquors (676 ± 195 mg L(-1)), and studied for 479 days under variations in hydraulic retention time. The main purpose of this work, was the study of dynamics abundance of total bacteria and single-cells nitrifying bacteria belonging to ammonia-oxidizing bacteria (AOB) and nitrite-oxidizing bacteria (NOB) in biofilms and mixed liquor of the plant. The microbial monitoring was successfully achieved using fluorescence in situ hybridization combined with flocs disaggregation protocol as a useful microbial monitoring tool. A partial nitrification process with a N-NH4(+) removal rate of about 38.6 ± 14.8% was successfully achieved at 211 days after start-up, with a clear dominance of AOB, which accounted for 11.3 ± 17.0% of total bacterial cells compared with only 2.1 ± 4.0% of NOB. The effluent obtained was subsequently supplied to an Anammox reactor for complete ammonium treatment.
authors.affiliation: Department of Microbiology, Faculty of Biology, University of Barcelona, Av. Diagonal 643, 08028 Barcelona, Spain. Electronic address: tabzazou@ub.edu.
authors.forename: Tarik
authors.initials: T
authors.lastname: Abzazou
authors.affiliation: Department of Microbiology, Faculty of Biology, University of Barcelona, Av. Diagonal 643, 08028 Barcelona, Spain. Electronic address: raraujo@ub.edu.
authors.forename: Rosa M
authors.initials: RM
authors.lastname: Araujo
authors.affiliation: ACCIONA AGUA, S.A., Av de les Garrigues 22, El Prat de Llobregat, 08820 Barcelona, Spain. Electronic address: maria.auset.vallejo@acciona.com.
authors.forename: María
authors.initials: M
authors.lastname: Auset
authors.affiliation: Department of Animal Biology, Faculty of Biology, University of Barcelona, Av. Diagonal 643, 08028 Barcelona, Spain. Electronic address: hsalvado@ub.edu.
authors.forename: Humbert
authors.initials: H
authors.lastname: Salvadó
mesh_terms: D001419:Bacteria / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D019149:Bioreactors / Q000382:microbiology*; D058465:Nitrification / Q000502:physiology*; D014865:Waste Disposal, Fluid / Q000379:methods*
keywords: AOB; FISH; MBBR; NOB; Partial nitrification