title: Effect of a microbiota activator on accumulated ammonium and microbial community structure in a pilot-scale membrane bioreactor.
abstract: Microbiota activators (MAs) have been used to improve the reactor performances of biological wastewater treatment processes. In this study, to remove ammonium (NH4(+)) accumulated during the pre-operation of a pilot-scale membrane bioreactor (MBR) under high-organic-loading conditions, an MA was added to the MBR system and the resulting changes in reactor performances and microbial communities were monitored for 12 days. The NH4(+) concentrations in the sludge and effluent decreased (from 427 to 246 mg/L in the sludge (days 1-9)), and mixed liquor suspended solid increased (from 6,793 to 11,283 mg/L (days 1-12)) after the addition of MA. High-throughput Illumina sequencing of 16S rRNA genes revealed that the microbial community structure changed along with the NH4(+) removal resulting from the MA addition. In particular, the relative abundance of an Acidovorax-related operational taxonomic unit (OTU) increased significantly, accounting for approximately 50% of the total microbial population at day 11. In contrast, the ammonia-oxidizing bacteria and archaea showed low abundances (<0.05%), and no anaerobic ammonia oxidizers were detected. These results suggested that the Acidovorax-related OTU was mainly involved in the NH4(+) removal in the MBR, probably due to its ammonia-assimilating metabolism.
authors.affiliation: Environmental Management Research Institute, National Institute of Advanced Industrial Science and Technology (AIST).
authors.forename: Yuya
authors.initials: Y
authors.lastname: Sato
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Hori
authors.forename: Ronald R
authors.initials: RR
authors.lastname: Navarro
authors.forename: Navarro R
authors.initials: NR
authors.lastname: Ronald
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Habe
authors.forename: Atsushi
authors.initials: A
authors.lastname: Ogata
mesh_terms: D064751:Ammonium Compounds / Q000378:metabolism*; D000693:Anaerobiosis; D001105:Archaea / Q000254:growth & development / Q000378:metabolism; D001419:Bacteria / Q000145:classification / Q000254:growth & development / Q000378:metabolism*; D019149:Bioreactors; D059014:High-Throughput Nucleotide Sequencing; D059013:Microbial Consortia; D064307:Microbiota; D009584:Nitrogen / Q000378:metabolism; D010865:Pilot Projects; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012722:Sewage / Q000382:microbiology; D014865:Waste Disposal, Fluid / Q000379:methods*; D062065:Wastewater
chemical_list: D064751:Ammonium Compounds; D009584:Nitrogen; D012336:RNA, Ribosomal, 16S; D012722:Sewage; D062065:Wastewater