Chemical composition of extracellular polymeric substances and evolution of microbial community in activated sludge exposed to ibuprofen. (15th September 2019)

• Record Type: Journal Article
• Authors: Zhou, Guangqing; Li, Na; Rene, Eldon R.; Liu, Qi; Dai, Meixue; Kong, Qiang
• Is Part Of: Journal of environmental management. Volume 246(2019)
• Page Start: 267
• Page End: 274
• Publication Date: 2019-09-15
• Subjects: Activated sludge -- Ibuprofen -- Extracellular polymeric substances -- Microbial community; Environmental policy -- Periodicals; Environmental management -- Periodicals; Environment -- Periodicals; Ecology -- Periodicals; 363.705
• DOI: 10.1016/j.jenvman.2019.05.044
• Languages: English
• ISSNs: 0301-4797

Abstract

Abstract: Ibuprofen (IBU) containing wastewater with a concentration of 1–5 mg/L was treated in an activated sludge sequencing batch reactor (SBR), for 60 days, in order to investigate the overall performance of the SBR, the parameter variations during a typical cycle, the chemical composition and content of extracellular polymeric substances (EPS) and the evolution of microbial community. The average removal efficiencies of COD, NH4 + -N and TN were >85%, while >40% of the IBU was removed and the removal efficiencies of TP fluctuated around ~ 75%. The EPS content increased significantly with IBU addition ( p < 0.01). Fulvic acid-like substances in the chemical composition of EPS increased during the stable operation phase. Proteobacteria associated with nitrogen removal was the dominant phylum, which can also resist IBU stress. For the denitrifying bacteria, the OTUs of both Rhodobacter and Pseudomonas increased from day 1–30 and reduced on day 60 ( p < 0.01), which was opposite to the results observed for Rhodocyclaceae (phosphorus-accumulating bacteria). The OTUs of Acidovorax showed an increasing trend ( p < 0.01), whereas the OTUs for Nitrospira (nitrite oxidizers) and Nitrosomonas (ammonia oxidizers) decreased significantly ( p < 0.05). Graphical abstract: Image 1 Highlights: Good removal efficiency of COD, NH4 + -N, TN, TP and ibuprofen was attained. After adding ibuprofen, the content of EPS (PN and PS) highly significant increased ( p < 0.01). Read numbers of partial DNB and PAO highly significant increased ( p < 0.01). Proteobacteria associated with nitrogen removal was the dominant phylum.