Tuesday, July 31, 2007 - 3:00 PM
S110
Enhanced biohydrogen production from biomass-derived substrates
Akihito Yoshida1, Masayuki Inui2, and Hideaki Yukawa2. (1) Research Department II, Advanced Materials Research Laboratories, Sharp Corporation, 2613-1, Ichinomoto-cho, Tenri, 632-8567, Nara, Japan, (2) Microbiology Research Group, Research Institute of Innovative Technology for the Earth, 9-2, Kizugawadai, Kizugawa, Kyoto, Japan
Hydrogen is a most promising alternative energy carrier given the projected depletion of fossil fuels and the development of fuel cells for cars, portable electric devices, etc. Hydrogen is currently produced chemically by refining oil or natural gas at high temperatures and pressures. In contrast, biological hydrogen production occurs at ambient temperatures and pressures. Furthermore, it has the striking merit of obviating production of carbon monoxide, which is harmful to the electrodes of fuel cells.
For commercially viable biohydrogen production, it is necessary to overcome two main limiting factors, namely, a low hydrogen yield from raw materials and a low volumetric hydrogen production rate. Low hydrogen yield was attributed to excreted by-products from raw materials for facilitating cell growth and maintaining reduction-oxidation balance, and low volumetric productivity was attributed to a low hydrogen production rate per cell and low cell density, which resulted from a low growth rate under anaerobic conditions. In order to overcome these issues, genetic modification and process engineering for efficient hydrogen production are indispensable.
In this presentation, we present on a process for biohydrogen production that uses Escherichia coli strains whose anaerobic pathways relating to hydrogen metabolism were genetically modified at high cell density to utilize formic acid and glucose as biomass-derived substrates, resulting in improved volumetric hydrogen production rate and hydrogen yield drastically. These striking results have the potential to enable the construction of biofuel-powered small appliances.
For commercially viable biohydrogen production, it is necessary to overcome two main limiting factors, namely, a low hydrogen yield from raw materials and a low volumetric hydrogen production rate. Low hydrogen yield was attributed to excreted by-products from raw materials for facilitating cell growth and maintaining reduction-oxidation balance, and low volumetric productivity was attributed to a low hydrogen production rate per cell and low cell density, which resulted from a low growth rate under anaerobic conditions. In order to overcome these issues, genetic modification and process engineering for efficient hydrogen production are indispensable.
In this presentation, we present on a process for biohydrogen production that uses Escherichia coli strains whose anaerobic pathways relating to hydrogen metabolism were genetically modified at high cell density to utilize formic acid and glucose as biomass-derived substrates, resulting in improved volumetric hydrogen production rate and hydrogen yield drastically. These striking results have the potential to enable the construction of biofuel-powered small appliances.