Characteristics of microbial community in EGSB system treating with oxytetracycline production wastewater

• Published in: Journal of environmental management 2021-10, Vol.295, p.113055-113055, Article 113055
• Main Authors: Chen, Hongying, Liu, Gaige, Wang, Ke, Piao, Chenyu, Ma, Xiaochen, Li, Xiang-Kun
• Format: Article
• Language: English
• Subjects: Anaerobic treatment; EGSB; Microbial community; Molecular ecological networks; Oxytetracycline production wastewater
• ISSN: 0301-4797; 1095-8630
• DOI: 10.1016/j.jenvman.2021.113055

In order to realize the efficient and stable operation of anaerobic digestion for oxytetracycline (OTC) production wastewater which contains high concentration refractory organic matters and antibiotic residues, two laboratory-scale EGSB reactors (the experimental reactor and the control reactor) were constructed for pre-treating OTC production wastewater and the complex characteristics and connections among anaerobic fermentative bacteria, methanogens and fungi were analyzed. The experimental reactor gradually increased OTC doses of 0–200 mg/L by four phases compared with the control reactor which was fed without OTC addition during 280 days’ operation. The average COD removal efficiency of 91.44% with the average OTC removal efficiency of 27.90% was achieved at OTC concentration of 200 mg/L. The addition of OTC did not affect the preponderant methanogen type, and Methanosaeta, a strict aceticlastic methanogen genus, was dominant both in working and controlling reactors on day 280. Redundancy analysis revealed that OTC and VFAs were the main environmental factors affecting the microbial communities and molecular ecological networks analysis indicated that the key genera principally belonged to Methanosaeta, Proteobacteria and Apiotrichum. Additionally, the fungi genus Apiotrichum might be related to the degradation of complex organic contaminants in OTC production wastewater treatment system. •91.44% removal of COD were achieved in EGSB reactor with 200 mg/L OTC in influent.•Enrichment of Thermovirga and Desulfovibrio enhanced the reactor performance.•Acetoclastic methanogenesis was predominant in both reactors.•The fungi Apiotrichum benefited for degradation of complex organic contaminants.•MENs analysis revealed the connections among keystone species.