Microbial Fuel Cells utilise electricigens for the production of electrical current in a microbial fuel cell. Electricigens are microorganisms able to utilize external insoluble electron acceptors, such as electrodes, as a final electron acceptor during respiration. In microbial fuel cells electricigens catalyse the oxidation of organic compounds utilising an anode as an electron acceptor. Microbial fuel cells and the microorganisms associated with them have been investigated for their potential applications in the production of electricity and biofuels, as well as bioremediation of wastewater and the environment.
Plants have also been integrated into microbial fuel cells to create plant microbial fuel cells. In these systems, organic compounds originating from plants, such as root exudates, can be utilized by electricigens and contribute to the power output of the microbial fuel cell. In effect creating a biological conversion of solar energy into electricity. Furthermore, microorganisms can promote the growth of plants. Microorganisms that promote plant growth have been under investigation for some time, however it remains relatively unknown whether electricigens can influence the growth of plants. Root exudates of plants are known to influence the growth of microbial communities, however it is unknown if this influence may enrich the presence of electricigens.
This project aims to investigate the interactions between photosynthetic organisms and microbial communities, including electricigens, within plant microbial fuel cells, with the goal of enhancing the efficiency of these devices. Traditional culturing and biochemical assays are being used to evaluate the ability of electricigens to perform known plant growth promotion processes. Community based techniques will investigate the development of microbial community structure in response to the presence of plants. Initial results showed the presence of connected microbial fuel cell circuitry significantly improved the growth of plants. Furthermore, the microbial community structure of plant microbial fuel cells was found to respond to the presence of plants. These results suggest the potential for benefits to plant growth within plant microbial fuel cells.