Organics and Nutrient Transformation in a Microbial Fuel Cell Influenced by Antibiotics

The present research focuses on the effect of the highly toxic and broad-spectrum bacteriostatic antibiotic pollutant, tetracycline (TC) as a sole electron donor and co-electron donor on the operational efficacy of a microbial fuel cell (MFC) in terms of nutrient and pollutants removal. It is observed that the removal efficiency of the MFC increases by the gradual increase in TC concentration (5-30 mg L-1). The maximum removal efficiency (59%), voltage production (372 mV), power density (81.4 mW m(-2)), and current density (232.5 mA m(-2)) are achieved in the MFC with 25 mg L-1 of TC. Moreover, the influential role of TC as a co-substrate is also investigated using three substrates viz, acetic acid, sucrose, and albumin. The current results suggest that chemical oxygen demand (COD) removal efficiency, coulombic efficiency, and voltage output of each substrate are inversely proportional to the amount of TC and are in the order of acetic acid > sucrose > albumin. The nutrient removal efficiency of the MFC decreases with an increase in TC concentration, i.e., when TC is increased from 10 to 50 mg L-1, the nitrogen removal efficiency decreases from 78% to 38%, the sulfur removal efficiency decreases from 79% to 32%, and the phosphorous removal efficiency decreases from 72% to 24%. The results suggest that an MFC can be upgraded for large-scale biological processes for antibiotic pollutant removal. Moreover, the adverse effect of TC in power generation of an MFC can serve as a biosensor for biological wastewater treatment processes to detect the antibiotic toxicity.