Two-stage photobiological hydrogen production of Platymonas subcordiformis cells at different growth phases under two kinds of light intensity
两种光强条件下亚心形扁藻各生长阶段的产氢能力

A marine green microalga, Platymonas subcordiformis, was able to generate H2 photo-synthetically when exposed to light after a period of anaerobic, dark incubation. The growth curves were different at different kinds of light intensity, and the ability of H2 production varied significantly at different growth phases. At higher light intensity(E=13 000 lx), the microalga grew faster, and gave a higher H2 yield. At the stationary phase, the ability of H2 production reached the maximum hydrogen concentration of 17.5% collected in 300 mL Culture at 3×106 cells/mL. At lower light intensity(E=5 000 lx), the H2 yield decreased by 24% with the maximimum hydrogen concentration of 17.5%,and the chlorophyll concentration reduced by 61%. The results indicated that the physiological status of algal cells has a significant effect on the ability of H2 production. Therefore optimization of physiological parameters is required to maximize hydrogen production in green algae