Microbial community response to ciprofloxacin toxicity in sponge membrane bioreactor

This study aims to offer insights into how ciprofloxacin (CIP) impact bacterial community structures in the Sponge-MBR process when CIP is spiked into hospital wastewater. We found that the CIP toxicity decreased richness critical phylotypes such as phylum class delta-, beta-, gamma-proteobacteria, and Havobacteria that co-respond to suppress denitrification and cake fouling to 37% and 28% respectively. Cluster analysis shows that the different community structures were formed under the influence of CIP toxicity. CIP decreased attached growth biomass by 2.3 times while increasing the concentration of permeate nitrate by 3.8 times, greatly affecting TN removal by up to 26%. Ammonia removal was kept stable by inflating the ammonia removal rate (p < 0.003), with the wealthy Nitrospira genus guaranteeing the nitrification activity. In addition, we observed an increasing richness of Chloroflexi and Planctornycetes, which may play a role in fouling reduction in the Sponge-MBR. Theretbre, if the amount of antibiotics in hospital wastewater continues to increase, it is so important to extend biomass retention for clenitrification recovery. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

This study reveals the impact of CIP on bacterial community structures in the Sponge-MBR process, reducing the richness of critical phylotypes and affecting the removal efficiency of nitrogen and ammonia in wastewater treatment.