两种光强条件下亚心形扁藻各生长阶段的产氢能力

海洋亚心形扁藻(Platymonas subcordiformis)在光照生长后,经过暗培养诱导其可逆产氢酶,然后转移到光照下可产生氢气。在300 mL产氢反应器中对海洋亚心形扁藻产氢情况的考察表明,不同的光强条件可导致扁藻产生不同的生长曲线,而在不同的培养阶段,扁藻的产氢能力也有很大的差别。其他培养条件相同,高光照强度(E=13000 lx)条件下,扁藻生长较快,而且可以获得更大的产氢能力,300 mL密度为3×106个/mL、叶绿素质量浓度为5.8 mg/L的藻液最大产氢浓度可达17.5%,比低光照强度(E=5000 lx)时提高了32%,叶绿素含量降低了61%。根据产氢前后以及暗诱导后扁藻生理状态的考察结果,可以推测出是不同生长阶段扁藻的生理状态差异导致了其产氢能力的变化。

Two-stage photobiological hydrogen production of Platymonas subcordiformis cells at different growth phases under two kinds of light intensity

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