CONSTRUCTION OF DOUBLE CHAMBERED MICROBIAL FUEL CELL (MFC) USING HOUSEHOLD MATERIALS AND BACILLUS MEGATERIUM ISOLATE FROM TEA GARDEN SOIL

Abstract

The current study was carried out for the isolation and screening of potential bioelectricity generating bacteria from tea garden soil samples and also to construct an indigenous microbial fuel cell (MFC) using house hold materials. Bacillus megaterium was found to the best isolate for the production of bioelectricity, out of a total of 25 bacterial isolates from soil samples of Lepetkata Tea Estate of Dibrugarh district of Assam. The isolate was identified on the basis of staining techniques and biochemical characteristics. Double chambered MFC was constructed by using two poly acrylic containers of 500 ml volume each. The two chambers were connected using an agar salt bridge and carbon rods were used as electrodes. The electricity generated by the isolate was compared using glucose and fructose as sole carbon source in minimal media. The maximum voltage was found to be 440 mV in presence of glucose as sole carbon source after 84 hrs of incubation at room temperature. The voltage was further increased up to 698 mV after the media was supplemented with 1.5 % (w/v) yeast extract, which would have served as additional source of vitamin to the bacteria to proliferate. During the entire study, the experimental set up was allowed to incubate at room temperature and occasional shaking was done manually, hence no external electricity was required. With all the above features the isolate Bacillus megaterium was found to be a good source of bioelectricity.