Sulfides play an important role in the photobiological production of H-2 from microalgae. Apart from the conventional sulfur deprivation strategy, the addition of sulfides is also found to promote the hydrogen production and biomass of microalgae. However, it is still unclear that how different sulfides influence the biomass and hydrogen production of algae. Here, an evaluation of various sulfides for enhancing the photobiological hydrogen production by co-cultivation of Chlamydomonas reinhardtii and Thiomonas intermedia was systematically investigated. Our results show that the addition of different sulfides can improve the biomass and photobiological hydrogen production of algae, and sodium thiosulfate (Na2S2O3) displays the best efficacy with a maximum H-2 photoproduction rate of 255.52 mu mol/mg Chl, which was 5.9 times higher than that of the pure algal culture. Notably, sustained H-2 production can be achieved by intermittent supplement of sulfides. Moreover, the effects of different sulfides on various physiological factors, such as starch accumulation, respiration rate and hydrogenase activity of the algae were also evaluated. This report provides the fundamental information for an enhanced and sustainable photobiological production of renewable hydrogen using microalgae.

Chlamydomonas reinhardtii CC-503; Thiomonas intermedia; Co-cultivation; Hydrogen production; Sulfides

China University of Petroleum (Huadong)