Inducing laccase activity in white rot fungi using copper ions and improving the efficiency of azo dye treatment with electricity generation using microbial fuel cells

This work presents a white rot fungus-microbial fuel cell (WRF-MFC) that uses WRF that is grown at its cathode. Adding Cu2+ to the fungi-containing solid medium stimulated WRF-secreting laccase, which catalyzed the redox reaction in the MFC and thereby promoting the generation of electricity. Adding 12.5 mg L-1 Cu2+ to a G. lucidum-containing medium provided the greatest laccase stimulation and increased the laccase activity by a factor of 1.6. Adding 12.5 mg L-1 Cu2+ to the WRF chamber of WRFMFC increased its decolorization of Acid Orange 7 (AO-7) and increased its power density to 223 mW m(-2), which was 1.77 times that of an MFC without WRF. The enhancement of decolorization and electricity generation improved the performance of the WRF-MFC, indicating that a laccase-catalyzed cathode has great potential effectiveness in microbial fuel cells. (C) 2019 Elsevier Ltd. All rights reserved.