Upgrading Conversion of Corncob to Furan Amino Acid via Cascade Catalysis of Solid Acid and Whole-Cell Catalyst

The sustainable synthesis of valuable noncanonical amino acids from renewable raw materials holds significant importance. This research developed a viable chemical–biological coupling process, leveraging the synergistic effect of a solid acid catalyst and the whole cell of E. coli PpLTA to selectively synthesize β-(2-furanyl) serine from corncob. Initially, a novel magnetic solid acid catalyst, Fe3O4/C-SO3H, was successfully fabricated and employed to catalyze the degradation of corncob in a toluene–water biphasic system for furfural production. Under the optimal conditions (catalyst loading of 2.0% w/w and reaction at 170 °C for 20 min), the furfural yield could attain 62.3%. After ten cycles of use, the yield of furfural remained at 44.7% and the retention rate of catalytic activity was 71.7%. Furthermore, the biocompatibility verification results demonstrated that the furfural derived from corncob could be completely transformed by E. coli PpLTA at a concentration of 50 mM, and this furfural system did not generate any by-products that hindered the biotransformation process. This chemical–biological coupling approach offers a technical solution for the efficient production of noncanonical amino acids from biomass resources.