Effect of ibuprofen on extracellular polymeric substances (EPS) production and composition, and assessment of microbial structure by quantitative image analysis

A Sequencing Batch Reactor (SBR) with activated sludge was operated synthetic wastewater containing ibuprofen (IBU) to investigate the biomass stress-responses under long-term IBU exposure. There were 3 different phases: phase I as control without for 56 days, II (40 days), and III (60 days) at 10 5 mg L?1 each. The overall performance of SBR well extracellular polymeric substances (EPS) in terms polysaccharides, proteins, humic acid estimated. Morphological parameters microbial aggregates presence (phase III) assessed by quantitative image analysis (QIA). Removal efficiencies chemical oxygen demand (COD) ammonium (NH4+) significantly reduced IBU. Loosely bound EPS (LB-EPS) decreased during III, tightly (TB-EPS) slightly higher than I. TB-EPS proteins greater II, perhaps protect cells from These findings provided insight into both composition Spearman correlation showed that morphological affected settleability flocculation. QIA also proved be a powerful technique investigating dysfunctions