초록
<P><B>Abstract</B></P> <P>Eucalyptus has been previously suggested as a potential substrate for acetone-butanol-ethanol (ABE) production without nutrient supplementation; however, incomplete sugar consumption has prevented improvement of ABE production. Cellulase loading with 35 FPU g<SUP>−1</SUP> was first optimized in terms of high hydrolysis efficiency (95%). However, only 0.43 g L<SUP>−1</SUP> ABE production and 3.44% glucose consumption rate were achieved. To improve ABE production from eucalyptus hydrolysate, supplementation of 6 nutrients in common tryptone-yeast extract (TY) medium were investigated by statistical approaches. Three nutrients including yeast extract, tryptone, and FeSO<SUB>4</SUB>·7H<SUB>2</SUB>O were screened as significant nutrients for ABE production. Subsequently, use of a modified TY medium (MTY medium: yeast extract 3.04 g L<SUP>−1</SUP>, tryptone 7.64 g L<SUP>−1</SUP>, FeSO<SUB>4</SUB>·7H<SUB>2</SUB>O 15.3 mg L<SUP>−1</SUP>), which was subsequently predicted by Plackett-Burman and Box-Behnken designs to stimulate ABE production, resulted in ca. 40-fold increase in ABE concentration (16.9 g L<SUP>−1</SUP>) and a glucose consumption rate of 100%. We first examined previously uninvestigated nutrition combinations using Plackett-Burman and Box-Behnken designs for high ABE production from eucalyptus hydrolysate. This study shows that statistical method would be a powerful tool for the optimization and enhancement of ABE production from eucalyptus hydrolysate.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Three kinds of significant nutrients were screened by the Plackett-Burman design. </LI> <LI> Box-Behnken designs are effective for optimization of nutrient concentrations. </LI> <LI> This is the first report to use statistical method for ABE production from eucalyptus. </LI> <LI> ABE production from eucalyptus hydrolysate was enhanced to 16.9 g L<SUP>−1</SUP> in MTY medium. </LI> </UL> </P>