Abstract

Microbial fuel cells (MFCs) generate electrical energy using microorganisms as biocatalysts to convert the chemical bonds of organic compounds in wastewater into electricity. Specific types of electrogenic bacteria that form biofilms on MFC electrodes when exposed to high-protein fish-processing wastewater have not been reported. The purpose of this study was to isolate and determine the characteristics of biofilm bacteria on the microbial fuel cell electrodes and identify the selected bacterial isolates. The bacterial growth media used were nutrient agar (NA), deMAnn Rogosa Sharpe Agar (MRSA), and thioglycollate agar (TGA). The characterization of the bacterial isolates included Gram staining, shape, protease activity, catalase activity, and motility. The selected isolates representing each medium and electrode were identified by PCR. Thirteen isolates were gram-positive with distinct characteristics. Molecular identification of the six selected isolates showed that the K1B isolate was Pediococcus pentosaceus; A1G, A2G and K1G isolates were Pediococcus acidilactici; A1T2 isolate was Bacillus subtilis and A3T2 isolate was Staphylococcus warneri.