초록
<P><B>Abstract</B></P> <P>Cotton stalk, a widely available and cheap agricultural residue lacking economic alternatives, was subjected to steam explosion in the range 170–200°C for 5min. Steam explosion at 200°C and 5min led to significant hemicellulose solubilization (71.90±0.10%). Alkaline extraction of steam exploded cotton stalk (SECOH) using 3% NaOH at room temperature for 6h led to 85.07±1.43% lignin removal with complete hemicellulose solubilization. Besides, this combined pretreatment allowed a high recovery of the cellulosic fraction from the biomass. Enzymatic saccharification was studied between steam exploded cotton stalk (SECS) and SECOH using different cellulase loadings. SECOH gave a maximum of 785.30±8.28mg/g reducing sugars with saccharification efficiency of 82.13±0.72%. Subsequently, fermentation of SECOH hydrolysate containing sugars (68.20±1.16g/L) with <I>Saccharomyces cerevisiae</I> produced 23.17±0.84g/L ethanol with 0.44g/g yield.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Steam exploded cotton stalk can be promising substrate for ethanol production. </LI> <LI> Steam explosion at 200°C and 5min led to 71.90% hemicellulose solubilization. </LI> <LI> SECOH showed 85.07% lignin reduction with complete hemicellulose solubilization. </LI> <LI> Steam explosion coupled with NaOH extraction showed promising sugar yield. </LI> <LI> Fermentation with <I>S. cerevisiae</I> strain produced 0.44g/g ethanol yield. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>