A New Hydrogen-Producing Strain and Its Characterization of Hydrogen Production.

Abstract

A newly isolated photo non-sulfur (PNS) bacterium was identified as Rhodopseudomonas palustris PB-Z by sequencing of 16S ribosomal DNA (rDNA) genes and phylogenetic analysis. Under vigorous stirring (240rpm), the hydrogen production performances were greatly improved: The maximum hydrogen production rate and cumulative hydrogen production increased by 188.9 ± 0.07 % and 83.0 ± 0.06%, respectively, due to the hydrogen bubbles were immediately removed from the culture medium. The effects of different wavelength of light on hydrogen production with stirring were much different from that without stirring. The ranking on the photo-hydrogen production performance was white > yellow > green > blue > red without stirring and white > yellow > blue > red > green under stirring. The best light source for hydrogen production was tungsten filament lamp. The optimum temperature was 35°C. The maximal hydrogen production rate and cumulative hydrogen production reached 78.7 ± 2.3ml/l/h and 1728.1 ± 92.7mol H2/l culture, respectively, under 35°C, 240rpm, and illumination of 4000lux. Pyruvate was one of the main sources of CO2 and has a great impact on the gas composition.