Synthesis of 5-Hydroxymethyl-2-furfurylamine from Bread Waste via Two-Step Reaction

Abstract

5-Hydroxymethyl-2-furfurylamine (HMFA) is an important furan chemical, which plays an important role in diuretics, antihypertensive drugs, and preservatives and can be obtained by amination of 5hydroxymethylfurfural (HMF). In this study, bread waste (BW) was chemoenzymatically transformed into HMFA via a one-pot two-step method through the tandem catalysis of deep eutectic solvent betaine/ formic acid (chemical catalyst) and Escherichia coli HILF cells (biocatalyst). First, the catalyst betaine/formic acid (10.0 wt %) was applied to catalyze BW (20.0 g/L) at 180 °C for 80 min, and the HMF yield reached 0.269 g HMF/g BW. Furthermore, coexpression of ω-transaminase HNIL [His (H) at AT210 was mutated to Asn (N) and Ile (I) at AT77 was mutated to Leu (L) in Aspergillus terreus transaminase] and lactate dehydrogenase (LDH) coupled with formate dehydrogenase (FDH) was utilized for biological amination and coenzyme regeneration, and the recombinant E. coli HILF was constructed by constructing a three-enzyme cascade catalytic reaction system. Using whole cells of HILF as a biocatalyst, the additional amount of D-alanine supplemented into the biological amination reaction was apparently reduced compared with that of the original transaminase. HILF cells could convert BW-derived HMF into HMFA (90.0% yield), and the yield was 0.243 g HMFA/g BW within 6 h. This hybrid strategy apparently reduced the dosage and cost of amine donors in biological amination and also laid the foundation for large-scale production of HMFA from BW.

Bread waste valorization: a review of sustainability aspects and challenges

“…They achieved a 30.3% yield of 5-HMF from BW in 45 min at 190°C. By using a specially engineered E. coli as a biocatalyst, they converted the 5-HMF into HMFA with a yield of 0.282 g HMFA/g BW at 35°C for 12 h. Gao et al (2023a) proposed an innovative approach for converting bakery waste into HMFA using a two-step method. This method involves tandem catalysis utilizing deep eutectic solvent betaine/formic acid as the chemical catalyst and Escherichia coli HILF as the biocatalyst.…”