One-pot conversion of biomass-derived xylose to furfuralcohol by a chemo-enzymatic sequential acid-catalyzed dehydration and bioreduction

One-pot furfuralcohol (FOL) production via dehydration of corncob-derived xylose followed by bioreduction of furfural has been described. The synthesized biocompatible solid acid catalyst SO42-/SnO2-attapulgite has been characterized and used for the dehydration of xylose-rich hydrolysate, and the highest furfural yield of 44% is achieved when employing 3.6 wt% catalyst loading at 170 degrees C for 20 min. The recombinant Escherichia coli CCZU-A13 harboring a NADH-dependent reductase (SsCR) is found to catalyze the bioreduction of furfural to FOL, the whole-cell catalyst could tolerate as high as 300 mM furfural substrate to give 221 mM FOL after 12 h of reaction under the optimum conditions (1.0 mM glucose per mM furfural, 30 degrees C, pH 6.5, 0.1 g wet cells per mL). The two processes are successfully combined in a one-pot manner to transform the xylose-rich hydrolysate to furfural, and then to FOL with 44% yield based on the starting material xylose (100% FOL yield for the bioreduction step). Finally, recycling experiments for the carrageenan immobilized whole-cell and solid acid catalyst in one-pot FOL production are conducted; both catalysts show excellent recyclability and no obvious decrease in activity is detected after 5 cycles of reaction. The developed one-pot chemo-enzymatic approach is greatly useful for practical green FOL production from renewable biomass resources.