초록
<P><B>Abstract</B></P> <P>Conversion of lignocellulosic biomass, such as corn stover (CS), to ethanol has encountered issues of inhibition from degradation products, low ethanol titer and low ethanol productivity. This work integrated CS into corn ethanol process for effective conversion. CS was pretreated using either dilute alkali or dilute acid pretreatment. The pretreated CS was enzymatically hydrolyzed and then mixed with liquefied corn for ethanol fermentation. Fermentation strains, substrate mixing ratios and fed-batch strategy were investigated. The mixture of alkali pretreated CS and corn at solids loadings of 10% and 20%, respectively, resulted in 92.30 g/L ethanol. Ethanol titer was further improved to 96.43 g/L with a fed-batch strategy. The mixture of dilute acid pretreated CS and corn achieved a better performance, leading to 104.9 g/L ethanol with 80.47% ethanol yield and a productivity as high as 2.19 g/L/h. This work demonstrated effective conversion of CS and corn together to ethanol.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Corn sugar stream was mixed with CS hydrolysate for ethanol fermentation. </LI> <LI> Mixture of 10% acid pretreated CS and 20% corn resulted in 104.9 g/L ethanol. </LI> <LI> Mixture of 10% alkali pretreated CS and 20% corn resulted in 92.3 g/L ethanol. </LI> <LI> Fed-batch of CS hydrolysate was developed to improve fermentation performance. </LI> <LI> Mixing in corn diluted toxic compounds in CS hydrolysate and improved fermentation. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>