title: Biodegradation and reversible inhibitory impact of sulfamethoxazole on the utilization of volatile fatty acids during anaerobic treatment of pharmaceutical industry wastewater.
abstract: This study evaluated the chronic impact and biodegradability of sulfamethoxazole under anaerobic conditions. For this purpose, a lab-scale anaerobic sequencing batch reactor was operated in a sequence of different phases with gradually increasing sulfamethoxazole doses of 1 to 45 mg/L. Conventional parameters, such as COD, VFA, and methane generation, were monitored with corresponding antimicrobial concentrations in the reactor and the methanogenic activity of the sludge. The results revealed that anaerobic treatment was suitable for pharmaceutical industry wastewater with concentrations of up to 40 mg/L of sulfamethoxazole. Higher levels exerted toxic effects on the microbial community under anaerobic conditions, causing the inhibition of substrate/COD utilization and biogas generation and leading to a total collapse of the reactor. The adverse long-term impact was quite variable for fermentative bacteria and methanogenic achaea fractions of the microbial community based on changes inflicted on the composition of the residual organic substrate and mRNA expression of the key enzymes.
authors.affiliation: Istanbul Technical University, Environmental Engineering Department, 34469 Maslak, Istanbul, Turkey; Catalan Institute for Water Research (ICRA), Emili Grahit 101, 17003 Girona, Spain. Electronic address: cetecioglu@itu.edu.tr.
authors.forename: Zeynep
authors.initials: Z
authors.lastname: Cetecioglu
authors.affiliation: Bogazici University, Institute of Environmental Sciences, Rumelihisarustu - Bebek, 34342 Istanbul, Turkey.
authors.forename: Bahar
authors.initials: B
authors.lastname: Ince
authors.affiliation: Catalan Institute for Water Research (ICRA), Emili Grahit 101, 17003 Girona, Spain.
authors.forename: Meritxell
authors.initials: M
authors.lastname: Gros
authors.affiliation: Catalan Institute for Water Research (ICRA), Emili Grahit 101, 17003 Girona, Spain.
authors.forename: Sara
authors.initials: S
authors.lastname: Rodriguez-Mozaz
authors.affiliation: Catalan Institute for Water Research (ICRA), Emili Grahit 101, 17003 Girona, Spain.
authors.forename: Damia
authors.initials: D
authors.lastname: Barceló
authors.affiliation: Istanbul Technical University, Environmental Engineering Department, 34469 Maslak, Istanbul, Turkey.
authors.forename: Orhan
authors.initials: O
authors.lastname: Ince
authors.affiliation: Istanbul Technical University, Environmental Engineering Department, 34469 Maslak, Istanbul, Turkey.
authors.forename: Derin
authors.initials: D
authors.lastname: Orhon
mesh_terms: D000693:Anaerobiosis; D001421:Bacteria, Anaerobic; D001673:Biodegradation, Environmental; D004345:Drug Industry; D005232:Fatty Acids, Volatile; D013420:Sulfamethoxazole / Q000032:analysis*; D014865:Waste Disposal, Fluid / Q000379:methods*; D062065:Wastewater / Q000737:chemistry*
chemical_list: D005232:Fatty Acids, Volatile; D013420:Sulfamethoxazole; D062065:Wastewater
keywords: Anaerobic biodegradation; Chronic inhibition; Enzyme expression; Metabolic pathways; Methanogenesis; RT Q-PCR; Sulfamethoxazole