Effects of different operating parameters on hydrogen production by Parageobacillus thermoglucosidasius DSM 6285.

Hydrogen gas represents a promising alternative energy source to dwindling fossil fuel reserves, as it carries the highest energy per unit mass and its combustion results in the release of water vapour as only byproduct. The facultatively anaerobic thermophile Parageobacillus thermoglucosidasius is able to produce hydrogen via the water-gas shift reaction catalyzed by a carbon monoxide dehydrogenase-hydrogenase enzyme complex. Here we have evaluated the effects of several operating parameters on hydrogen production, including different growth temperatures, pre-culture ages and inoculum sizes, as well as different pHs and concentrations of nickel and iron in the fermentation medium.