초록
<P><B>Abstract</B></P> <P>Three indigenous microalgae strains (<I>Scenedesmus subspicatus</I> GY-16, <I>Chlorella vulgaris</I> FSP-E, and <I>Anistrodesmus gracilis</I> GY-09) were evaluated for their ability to accumulate carbohydrates to subsequently serve as feedstock for biohydrogen production. The results of photoautotrophic growth show that among the three strains examined, <I>C. vulgaris</I> FSP-E displayed the highest biomass productivity (825.6 mg/L/d) and carbohydrate productivity (365.8 mg/L/d). Mixotrophic growth of <I>C. vulgaris</I> FSP-E with the addition of 2.0 g/l of sodium acetate further increased the biomass and carbohydrate productivity to 1022.3 mg/L/d and 498.5 mg/L/d, respectively. Moreover, operating photobioreactor on semi-batch mode enhanced the stability for prolonged incubation of the carbohydrate-rich <I>C. vulgaris</I> FSP-E and the biomass and carbohydrate productivity obtained were 1063.3 and 384.8 mg/L/d, respectively. The biomass of <I>C. vulgaris</I> FSP-E was then used as feedstock for biohydrogen production via separate hydrolysis and fermentation processes. The acidic hydrolysate (hydrolyzed with 1% H<SUB>2</SUB>SO<SUB>4</SUB>) was fermented with <I>Clostridium butyricum</I> CGS5, giving a maximum H<SUB>2</SUB> yield of 2.87 mmol H<SUB>2</SUB>/g biomass and a H<SUB>2</SUB> production rate of 176.9 ml/h<SUP>/</SUP>l, which are higher than most reported values. The results obtained in this work indicate that carbohydrate-based microalgae feedstock shows good potential for biohydrogen production.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Three microalgae strains were examined for the ability to accumulate carbohydrates. </LI> <LI> <I>Chlorella vulgaris</I> FSP-E had the highest biomass and carbohydrate productivity. </LI> <LI> Carbohydrate-rich <I>C. vulgaris</I> FSP-E was effectively hydrolyzed simply with 1% H<SUB>2</SUB>SO<SUB>4</SUB>. </LI> <LI> The microalgae hydrolysate was converted to H<SUB>2</SUB> with <I>C. butyricum</I> at high efficiency. </LI> <LI> Obtained microalgae-based bioH<SUB>2</SUB> production performance is better than literature. </LI> </UL> </P>