Abstract:
Antibiotics, as a class of antimicrobial drugs, have been widely used since their discovery. The abuse and improper discharge of antibiotics have led to their frequent detection in aquatic environments, posing severe threats to ecosystems and human health. Even at low concentrations, antibiotics can induce the emergence of antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARGs), severely disrupting the microbial community structure. Conventional treatment technologies exhibit limited removal efficiencies for antibiotics and are associated with high energy consumption. Furthermore, the complexity and toxicity of antibiotic wastewater make it difficult for conventional treatment processes to achieve effective antibiotic removal. The inhibitory effect of antibiotics on microorganisms can also impair the removal of conventional pollutants. The constructed wetland-microbial fuel cell (CW-MFC) system has emerged as a promising and synergistic green technology. This integrated system ingeniously combines the efficient, low-cost pollutant removal capacity of constructed wetlands with the ability of microbial fuel cells to recover bioenergy in situ and enhance the degradation processes. This coupled technology achieves the synergy between highly efficient pollutant degradation and in-situ bioelectricity generation. CW-MFC offers a promising new approach for achieving efficient, energy-saving and environmentally friendly treatment of antibiotic wastewater. This review outlines the fundamental structure and core mechanisms of CW-MFC. Comprehensively synthesizes the latest research progress and removal efficiency of CW-MFC system in treating various types of antibiotics, including sulfonamides, tetracyclines, and fluoroquinolones. The results showed that CW-MFC demonstrates significant potential and unique advantages in treating antibiotic wastewater, as a green and low-carbon water treatment technology. Emphasis is placed on elucidating the removal mechanisms of representative antibiotics within CW-MFCs, encompassing substrate adsorption, plant effects, microbial degradation, and electrochemical processes. The primary migration and transformation pathways of various antibiotics within the system are clarified. It also objectively assesses the current challenges in treating antibiotic wastewater, including the enrichment of functional bacteria, the risk of resistance gene transmission, long-term operational stability, and interference from complex water matrix components. Based on the existing research, we further propose targeted strategies for performance enhancement. These strategies highlight the development of advanced substrate materials, the directed regulation and optimization of functional microbial communities, and the precise control of operational parameters (including hydraulic retention time and external resistance) are identified as the pivotal levers for enhancing system efficacy. Future research directions were proposed focusing on key issues including the co-metabolic mechanisms of carbon sources, the ecological risks of intermediate products, and the dissemination of antibiotic resistance genes, which provide a theoretical reference for further research and engineering application of this technology.