초록
<P><B>Abstract</B></P> <P>Hydrogen generation from complex substrates composed of simple sugars has the potential to mitigate future worldwide energy demand. The biohydrogen potential of a sequential microaerobic dark- and photo-fermentative system was investigated using immobilized <I>Rhodobacter capsulatus</I> JP91. Biological hydrogen production from glucose was carried out using a batch process and a bench-scale bioreactor. Response surface methodology with a Box-Behnken design was employed to optimize key parameters such as inoculum concentration, oxygen concentration, and glucose concentration. The maximum hydrogen production (21 ± 0.25 mmol H<SUB>2</SUB>/L) and yield (7.8 ± 0.1 mol H<SUB>2</SUB>/mol glucose) were obtained at 6 mM glucose, 4.5% oxygen and 62.5 v/v% inoculum concentration, demonstrating the feasibility of enhanced hydrogen production by immobilized <I>R. capsulatus</I> JP91 in a sequential system. This is the first time that a sequential process using an immobilized system has been described. This system also achieved the highest hydrogen yield obtained by an immobilized system so far.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Sequential microaerobic dark- and photo-fermentative system investigated. </LI> <LI> H<SUB>2</SUB> from glucose using a batch process and a bench-scale bioreactor. </LI> <LI> H<SUB>2</SUB> by immobilized <I>R. capsulatus</I> JP91 in a sequential system demonstrated. </LI> <LI> Maximum H<SUB>2</SUB> production obtained at 6 mM glucose, 4.5% O<SUB>2</SUB>, 62.5 v/v% inoculum. </LI> </UL> </P>