A systematic review for degradation of tetracycline antibiotics by microbial fuel cells: Performance, mechanisms, microbial community and coupled system

Tetracycline antibiotics (TCs), as a type of antibiotics, are widely used in human and animal healthcare, and their residues are frequently detected in natural environments and pose serious threats to ecosystem safety. Microbial fuel cells (MFCs), combined the advantages of biodegradation and chemical degradation, have reported to be an emerging technology for TCs removal. This review comprehensively summarized the recent advancements of MFCs in the degradation of TCs, including the types of TCs degraded in MFCs, degradation mechanisms and pathways, functional microbial communities, inhibitory effects of TCs, coupling-enhanced systems, and prospects and challenges. TCs (such as tetracycline, chlortetracycline, and oxytetracycline) can be removed at the anode and/or cathode in MFCs. At the anode, TCs are mineralized to carbon dioxide and water by anodic microorganisms, achieving completely degradation; at the cathode under aerobic condition, TCs can be efficiently degraded through microbial co-metabolism and enzymatic transformation. Microbial community analysis revealed that the synergistic interaction between electroactive microorganisms and degradative microorganisms plays important roles in the efficient degradation of TCs and the enhancement of overall system performance. The mechanisms and performance of coupling-enhanced systems for TCs degradation have been proposed. This review highlighted the promising potential of MFCs for TCs degradation, while optimizing system scalability and environmental compatibility in the future for real-world application will be essential to antibiotic wastewater treatment.