초록
<P><B>Abstract</B></P> <P>In this work, the industrial <I>Saccharomyces cerevisiae</I> PE-2 strain, presenting innate capacity for xylitol accumulation, was engineered for xylitol production by overexpression of the endogenous <I>GRE3</I> gene and expression of different xylose reductases from <I>Pichia stipitis</I>. The best-performing <I>GRE3</I>-overexpressing strain was capable to produce 148.5 g/L of xylitol from high xylose-containing media, with a 0.95 g/g yield, and maintained close to maximum theoretical yields (0.89 g/g) when tested in non-detoxified corn cob hydrolysates. Furthermore, a successful integrated strategy was developed for the production of xylitol from whole slurry corn cob in a presaccharification and simultaneous saccharification and fermentation process (15% solid loading and 36 FPU) reaching xylitol yield of 0.93 g/g and a productivity of 0.54 g/L·h. This novel approach results in an intensified valorization of lignocellulosic biomass for xylitol production in a fully integrated process and represents an advance towards a circular economy.</P> <P><B>Highlights</B></P> <P> <UL> <LI> <I>Saccharomyces cerevisiae</I> PE-2 robust yeast was engineered for xylitol production. </LI> <LI> Recombinant strains were physiological characterized in with xylose and glucose. </LI> <LI> High xylitol yields (0.95–0.98 g/g) were obtained in batch and fed-batch cultures. </LI> <LI> Efficient xylitol production was obtained from non-detoxified corncob hydrolysates. </LI> <LI> Corn cob whole slurry was used for xylitol production by SSF process. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>