title: Effect of solids retention time on antibiotics removal performance and microbial communities in an A/O-MBR process.
abstract: The effect of solids retention time on reactor performance and microbial community composition in anoxic/aerobic membrane bioreactors (A/O-MBR) were investigated in this study. Experimental results showed high removal efficiencies of conventional pollutants. Antibiotics removal efficiencies were obviously affected by SRT changes. Longer SRT (above 30days) was proved to be suitable operational condition for antibiotics removal. Denaturing gradient gel electrophoresis (DGGE) and clone library analysis revealed that bacteria belong to Betaproteobacteria and Gammaproteobacteria were the dominant species during wastewater treatment and antibiotics removal. SRT significantly influenced the relative numbers of nitrifying bacteria. Removal efficiency of total nitrogen (TN) decreased when SRT was 3days, because nitrogen loading exceeded the denitrification ability of the reactors. Unlike tet C and tet E genes, sulfa antibiotics resistance gene presented a decreasing tendency with the decrease of SRT, and finally affected sulfa antibiotics removal efficiencies.
authors.affiliation: State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China. siqingxia@gmail.com
authors.forename: Siqing
authors.initials: S
authors.lastname: Xia
authors.forename: Renyong
authors.initials: R
authors.lastname: Jia
authors.forename: Fan
authors.initials: F
authors.lastname: Feng
authors.forename: Kang
authors.initials: K
authors.lastname: Xie
authors.forename: Haixiang
authors.initials: H
authors.lastname: Li
authors.forename: Danfeng
authors.initials: D
authors.lastname: Jing
authors.forename: Xiaotian
authors.initials: X
authors.lastname: Xu
mesh_terms: D000332:Aerobiosis; D000693:Anaerobiosis; D000900:Anti-Bacterial Agents / Q000302:isolation & purification*; D001419:Bacteria / Q000235:genetics / Q000378:metabolism*; D020562:Betaproteobacteria / Q000235:genetics; D001673:Biodegradation, Environmental; D019149:Bioreactors / Q000382:microbiology*; D058645:Denaturing Gradient Gel Electrophoresis; D058440:Denitrification; D024881:Drug Resistance, Bacterial / Q000235:genetics; D052918:Environmental Restoration and Remediation / Q000295:instrumentation* / Q000379:methods*; D018628:Gene Dosage / Q000235:genetics; D015723:Gene Library; D008567:Membranes, Artificial; D008969:Molecular Sequence Data; D058465:Nitrification; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D012722:Sewage / Q000382:microbiology*; D013997:Time Factors; D014874:Water Pollutants, Chemical
chemical_list: D000900:Anti-Bacterial Agents; D008567:Membranes, Artificial; D012336:RNA, Ribosomal, 16S; D012722:Sewage; D014874:Water Pollutants, Chemical