Analysis and in situ characterization of activated sludge communities capable of benzotriazole biodegradation

摘要: The aerobic biodegradation potential of benzotriazole (BTri), 4-, and 5-tolyltriazole (4-TTri, 5-TTri) by activated sludge communities (ASC), taken from three wastewater treatment plants (WWTP): a membrane bioreactor (MBR-MH), conventional plant (CAS-E) with intermittent nitrification/denitrification, CAS-plant (CAS-M) two-stage treatment, is evaluated. In small-scale setups (500 mL), 5-TTri (31.2 mg/L) BTri (34.0 mg/L) were eliminated under conditions. was removed after 7 days while the ASC showed significant differences concerning biodegradation. MBR-MH 21 days CAS-E CAS-M needed 42 49 days, respectively, but acclimation (49 days), all biodegraded within 7 days. larger-scale (10 L), 4 days, 96% (0.5 mg/L) already (1.0 mg/L) 4-TTri proved stable even 105 days in both setups, regardless concentration applied. Fluorescence situ hybridization (FISH) analysis revealed Alpha- Betaproteobacteria as dominant groups abundance Actinobacteria significantly decreased. aerobic, mesophilic conditions setups. Biodegradation fastest for 5-TTri, affected concentration: readily at low concentrations high slower not all. Additional experiments, using FISH technique to analyze structure, that two most likely are involved 5-TTri.