Novel and Efficient Biotechnological Approach to Produce 2,5-Diformylfuran from Biomass-Derived 5-Hydroxymethylfurfural

The preparation of compounds of interest from biomass-derived 5-hydroxymethylfurfural (HMF) has attracted considerable attention. One such compound is 2,5-diformylfuran (DFF), obtained through oxidation of the hydroxyl group of HMF. Herein, we describe for the first time the whole-cell oxidation of HMF to DFF by Fusarium culmorum EAN 51. Although the chemocatalytic transformation of HMF into DFF has been widely studied, biocatalytic processes have been scarcely reported and are limited to enzymatic synthesis using the combination of several enzymes. The whole-cell transformation of HMF into DFF is preferable thanks to the inherent presence of the different enzymes, significantly reducing the cost of the process. F. culmorum showed a high capability to reduce to 2,5-di(hydroxymethyl)furan (DHMF) and oxidize to DFF the substrate with high yields depending on the nitrogen source and the concentration of peptone and glucose in the media, which highly affected the redox capability of this strain. After careful optimization of the concentration of both nutrients through response surface methodology, 50 mM HMF were transformed into DFF with a high yield (92%) and selectivity (94%). These results open a new line of investigation in the sustainable production of DFF from renewable biobased resources.