Biofuel cells 204 fermentation

To compete in this arena, biofuel cells must take advantage of inherent biocatalytic properties that cannot be duplicated by conventional technology. Among these key properties are (1) activity at low temperature and near-neutral pH, (2) chemical selectivity, and (3) potentially low-cost production using fermentation and bioseparation technologies. To the extent possible, these properties must be exploited with minimal compromise of power density and stability. This constraint leaves one major class of conventional applications suitable for biofuel cells small fuel cells for portable power. 

Microbial biofuel cells were the earliest biofuel cell technology to be developed, as an alternative to conventional fuel cell technology. The concept and performance of several microbial biofuel cells have been summarized in recent review chapters." The most fuel-efficient way of utilizing complex fuels, such as carbohydrates, is by using microbial biofuel cells where the oxidation process involves a cascade of enzyme-catalyzed reactions. The two classical methods of operating the microbial fuel cells are (1) utilization of the electroactive metabolite produced by the fermentation of the fuel substrate " and (2) use of redox mediators to shuttle electrons from the metabolic pathway of the microorganism to the electrodes. ... 

Efremenko EN, Nikolskaya AB, Lyagin IV, Senko OV, Makhlis TA, Stepanov NA, Maslova OV, Mamedova F, Varfolomeev SD (2012) Production of biofuels from pretreated microalgae biomass by anaerobic fermentation with immobilized Clostridium acetobutylicum cells. Bioresour Technol 114 342-348... 

Rabaey, K., Lissens, G., Verstraete, W. (2005). Microbial fuel cells performances and perspectives. In P. Lens, P. Westerman, A. Haberbauer, A. Moreno (Eds.), Biofuels for fuel cells Renewable energy from biomass fermentation. London IWA Publishing. 

The presence of lignin in plant cell walls interferes with the fermentation to produce biofuels, and enzymes are the single largest processing cost component for bioconversion of biomass after the biomass itself. The transgenic switchgrass requires lower temperature preprocessing and only one-quarter to one-third the level of enzymes... 

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