title: Performance and microbial community variations in thermophilic anaerobic digesters treating OTC medicated cow manure under different operational conditions.
abstract: This study aimed to determine the fate and effect of oxytetracycline (OTC) and its metabolites during thermophilic anaerobic digestion of cow manure. OTC-medicated and non-medicated digesters were operated at 55°C with different volatile solids (VS) concentrations (4% and 6%) and mixing rates (90 and 120rpm). OTC and its metabolites were measured by HPLC and LC/MS/MS, respectively. Microbial community dynamics were monitored by denaturing gradient gel electrophoresis (DGGE) and real-time PCR (qPCR). Approximately 2mg/L initial OTC concentration caused 10-30% inhibition on biogas production and higher inhibition was observed as mixing rate increased. DGGE results indicated that OTC caused a shift in bacterial community structure and several species became dominant with time. Archaeal community decreased throughout the digestion period. RNA based qPCR analyses showed that gene copy numbers of bacteria and Methanomicrobiales declined in all digesters whereas gene copy numbers of Methanobacteriales and Methanosarcinales increased in high mixing rate digesters.
authors.affiliation: Institute of Environmental Sciences, Boğaziçi University, 34342 Istanbul, Turkey. Electronic address: cagri.akyol@boun.edu.tr.
authors.forename: Çağrı
authors.initials: Ç
authors.lastname: Akyol
authors.affiliation: Institute of Environmental Sciences, Boğaziçi University, 34342 Istanbul, Turkey.
authors.forename: Gokhan
authors.initials: G
authors.lastname: Turker
authors.affiliation: Department of Environmental Engineering, Faculty of Civil Engineering, Istanbul Technical University, 34469 Istanbul, Turkey.
authors.forename: Orhan
authors.initials: O
authors.lastname: Ince
authors.affiliation: Institute of Environmental Sciences, Boğaziçi University, 34342 Istanbul, Turkey.
authors.forename: Emine
authors.initials: E
authors.lastname: Ertekin
authors.affiliation: Department of Pharmacology and Toxicology, Faculty of Veterinary Medicine, Istanbul University, 34320 Istanbul, Turkey.
authors.forename: Oya
authors.initials: O
authors.lastname: Üstüner
authors.affiliation: Institute of Environmental Sciences, Boğaziçi University, 34342 Istanbul, Turkey.
authors.forename: Bahar
authors.initials: B
authors.lastname: Ince
mesh_terms: D000693:Anaerobiosis; D000818:Animals; D000900:Anti-Bacterial Agents / Q000032:analysis / Q000378:metabolism / Q000494:pharmacology*; D001105:Archaea / Q000187:drug effects / Q000235:genetics / Q000502:physiology; D056804:Biofuels; D019149:Bioreactors / Q000382:microbiology*; D002245:Carbon Dioxide / Q000378:metabolism; D002417:Cattle; D002851:Chromatography, High Pressure Liquid; D058645:Denaturing Gradient Gel Electrophoresis; D005260:Female; D006207:Half-Life; D006859:Hydrogen / Q000378:metabolism; D008372:Manure / Q000382:microbiology; D017018:Methanomicrobiales / Q000235:genetics / Q000502:physiology; D019640:Methanosarcinales / Q000187:drug effects / Q000378:metabolism / Q000502:physiology; D059013:Microbial Consortia / Q000187:drug effects* / Q000235:genetics / Q000502:physiology; D010118:Oxytetracycline / Q000032:analysis / Q000378:metabolism / Q000494:pharmacology*; D060888:Real-Time Polymerase Chain Reaction; D053719:Tandem Mass Spectrometry
chemical_list: D000900:Anti-Bacterial Agents; D056804:Biofuels; D008372:Manure; D002245:Carbon Dioxide; D006859:Hydrogen; D010118:Oxytetracycline
keywords: Cow manure; DGGE; Oxytetracycline; Real-time PCR; Thermophilic anaerobic digestion