초록
<P><B>Abstract</B></P> <P>Cornstalk is a typical cellulose material, which can be used by photo-fermentative H<SUB>2</SUB> production after pretreatment. However, the pretreatment methods have different influence on photo fermentation. In this study, 25.0 g cornstalk was pretreated by HCl/NaOH/cellusase. The hydrolysis rates increased from 45.51% by ddH<SUB>2</SUB>O-treatment to 60.79% by diluted HCl-treatment and 51.6% by NaOH-treatment. The corresponding reducing sugar yields were 0.13 g/g, 0.42 g/g and 0.01 g/g, respectively. Enzymatic treatment enhanced the corresponding cornstalk hydrolysis rates to 50.81%, 67.60% and 64.10% with reducing sugar yields of 0.22 g/g, 0.62 g/g and 0.26 g/g. The sorts and concentrations of carbon source for H<SUB>2</SUB> production vary among different hydrolysates. Photo-fermentative H<SUB>2</SUB> production of strain <I>R. capsulatus</I> JL1 and mutant JL1601 (<I>cheR2</I> <SUP> <I>-</I> </SUP>) with hydrolysates were investigated. The maximum H<SUB>2</SUB> yield of 123.8 ± 14.2 mL/g by strain JL1 was obtained from alkali-enzyme pretreated cornstalk, while the H<SUB>2</SUB> yield of 224.9 ± 5.2 mL/g by mutant JL1601 (<I>cheR2</I> <SUP> <I>-</I> </SUP>) was obtained with acid-enzyme hydrolysate as the substrates. Meanwhile, the alkali pretreated cornstalk was the worst for photo-fermentation of both strain JL1 and mutant JL1601 (<I>cheR2</I> <SUP> <I>-</I> </SUP>). Nevertheless, the highest substrate conversion efficiencies for both strains were obtained from ddH<SUB>2</SUB>O-pretreated hydrolysate. Two-step pretreated hydrolysates were more beneficial to H<SUB>2</SUB> production for mutant JL1601 (<I>cheR2</I> <SUP> <I>-</I> </SUP>) but not for strain JL1.</P> <P><B>Highlights</B></P> <P>We explored the compatibility between cornstalk-pretreatment and one-step photo fermentative H<SUB>2</SUB> production.<UL> <LI> The HCl/NaOH/cellusase were used to hydrolyze cornstalk alone or in combination. </LI> <LI> The H<SUB>2</SUB> yields by mutant JL1601 (<I>cheR2</I> <SUP> <I>-</I> </SUP>) from straw hydrolysates were enhanced except for HCl-pretreated cornstalk. </LI> <LI> The maximum H<SUB>2</SUB> production by wildtype JL1 and mutant JL1601 were obtained from different hydrolysates. </LI> </UL> </P>