초록
<P><B>Abstract</B></P> <P>The use of hot-water (100°C) from the 1st generation ethanol plants for mild-temperature lignocellulose pretreatment can possibly cut down the operational (energy) cost of 2nd generation ethanol process, in an integrated model. Dilute-sulfuric and -phosphoric acid pretreatment at 100°C was carried out for wheat bran and whole-stillage fibers. Pretreatment time and acid type influenced the release of sugars from wheat bran, while acid-concentration was found significant for whole-stillage fibers. Pretreatment led up-to 300% improvement in the glucose yield compared to only-enzymatically treated substrates. The pretreated substrates were 191–344% and 115–300% richer in lignin and glucan, respectively. Fermentation using <I>Neurospora intermedia</I>, showed 81% and 91% ethanol yields from wheat bran and stillage-fibers, respectively. Sawdust proved to be a highly recalcitrant substrate for mild-temperature pretreatment with only 22% glucose yield. Both wheat bran and whole-stillage are potential substrates for pretreatment using waste heat from the 1st generation process for 2nd generation ethanol.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Lignocellulose integration at 1st generation ethanol plants. </LI> <LI> Mild-temperature (100°C) pretreatment of wheat bran, stillage fiber and saw dust. </LI> <LI> Dilute acid pretreatment of wheat bran led up-to 300% improvement in glucose yield. </LI> <LI> Edible fungal fermentation of pretreated stillage fiber showed 91% ethanol yield. </LI> <LI> Proposed low energy approach of using waste-heat from 1G facility for 2G ethanol. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>