The objective of this study was to investigate the feasibility of pyridine biodegradation in the microbial fuel cell (MFC), from which electricity was generated. Experiments were initially conducted in a graphite-packed MFC (G-MFC) using a pyridine concentration of 500 mg/L combined with different glucose concentrations. Pyridine of 500 mg/L only used as the G-MIFC fuel resulted in a maximal voltage of 116 mV and a maximal power density of 1.7 W/m(3). The maximal voltage reached within 12 h when pyridine was totally depleted. The glucose supplement with concentrations of 500, 250, and 100 mg/L resulted in the maximum voltages of 623, 538, and 349 mV, respectively. correspondingly the maximal volumetric power densities were 48.5, 36.2. and 15.2 W/m(3). Pyridine biodegradation rates reached 95% within 24 h using the G-MFC. Interestingly, after 90 d of acclimation, the biodegradation rates of pyridine in the G-MFC using pyridine only as the fuel were higher than those using the glucose-pyridine mixtures. Further experiments were conducted using a graphite fiber brush MFC (B-MIFC). Compared to the G-MFC, the B-MFC enhanced the electrical charges by 89,186, and 586% for the mixtures with ratios of glucose-to-pyridine of 1:1, 1:2, and 1:5, respectively. GC/MS analyses of the anode solution indicated that the metabolism of pyridine in the MFC was initiated by ring reduction and NH3-N production. The results suggest that pyridine may be used as the MFC fuel in practical applications of wastewater treatment. Crown Copyright (C) 2009 Published by Elsevier B.V. All rights reserved.