The Role of Protease-Producing Bacteria in Microbial Fuel Cells

Document Type: Research Paper


Department of Microbiology, Payam Noor University, Sanandaj, Iran



Microbial fuel cells are devices that generate electricity by using the chemical energy which is hidden in the substrates.   Bacillus subtilis and Shewanella, connected in series, were used in order to increase the voltage. A bio cathode was used as an oxygen acceptor which was filled by Chlorella vulgaris. An amount of 200 mL molasses was used in the anode, and 200 mL BBM in the cathode. Nafion 115 was used as a PEM at 27˚C under microaerophilic conditions prepared for these experiments. At the same time as producing electricity, the basic protease was generated in the anode chamber containing B.subtilis. This protease was detected by Bradford’s test. The series connection of MFCs increased the voltage, and for the first time, we succeeded in producing biological products like enzymes in MFCs.