亚心型扁藻培养过程中元素缺乏对其生化组成及产氢量的影响

Platymonas subcordiformis, a marine green alga, was demonstrated to photo-biologically produce hydrogen when regulated by a proton uncoupler CCCP (Carbonyl Cyanide m-Chlorophenylhydrazone). This process composes of two stages: algal cultivation and hydrogen production. In the first stage the green alga grow to accumulate biomass and starch. In the second stage, the algal biomass is subjected to a period of dark anaerobic induction of hydrogenase activity and then exposed to light irradiation for photo-evolution of hydrogen using CCCP regulation. CCCP acts to create an anaerobic environment, essential for hydrogen production by reducing the photosystem II (PSII) activity (oxygen evolution) of P. subcordiformis cells below the respiration activity (oxygen consumption of intracellular carbohydrate). Therefore the carbohydrate content in algal cells determines the final hydrogen yield because hydrogen evolution will effectively stop as soon as it is completely consumed. In this! study, it was found that the nitrogen concentration in the medium influenced both the cell growth and also the starch content of P. subcordiformis cells in the first cultivation stage. Nitrogen limitation reduced biomass yield, but increased the carbohydrate content, resulting in higher hydrogen yiel