Effects of various antibiotics on aerobic nitrogen removal and antibiotic degradation performance: Mechanism, degradation pathways, and microbial community evolution

• Published in: Journal of hazardous materials 2022-01, Vol.422, p.126818-126818, Article 126818
• Main Authors: Liang, Donghui, Hu, Yongyou, Huang, Ruzhen, Cheng, Jianhua, Chen, Yuancai
• Format: Article
• Language: English
• Subjects: Achromobacter sp. JL9; Heterotrophic nitrification and aerobic denitrification; Long-term aerobic nitrogen removal-moving bed biofilm reactor; Selective stress; Total nitrogen removal efficiency
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/j.jhazmat.2021.126818

Little information about the selective stress of various antibiotics and how they influence different stages of aerobic nitrogen removal is available. A long-term aerobic nitrogen removal-moving bed biofilm reactor was established by the inoculation of Achromobacter sp. JL9, capable of heterotrophic nitrification and aerobic denitrification, and aerobic activated sludge. The nitrogen removal and antibiotic degradation performances of various antibiotics were then measured. High total nitrogen (91.83% and 91.51%) removal efficiencies were achieved with sulfamethoxazole or no antibiotics, and lower efficiencies were observed with other antibiotics (trimethoprim, teicoplanin, and ciprofloxacin). These results suggest that various antibiotics have different selective inhibitory effects on aerobic nitrogen removal. Additionally, all antibiotics were partly degraded; proposed degradation pathways according to the detected intermediates included ring-opening, S-N bond cleavage, amination, hydroxylation, and methylation. High-throughput sequencing indicated that aerobic denitrifying, recalcitrant pollutant degrading, and antibiotic-resistant bacteria dominate during the community evolution process. [Display omitted] •Antibiotics had different selective inhibitory effects on aerobic nitrogen removal.•Biofilms were able to remove nitrogen and various antibiotics.•Repeated addition of antibiotics causes the evolution of the community structure.•Selective stress of antibiotics affects nitrogen metabolic pathways in biofilm.