Biocatalytic Hydrogenation of Biomass-Derived Furan Aldehydes to Alcohols

The biomass-derived furan aldehydes furfural (FF) and 5-hydroxymethylfurfural (HMF) are versatile platform chemicals used to produce various value-added chemicals through further valorization processes. Selectively reducing C═O in FF and HMF molecules to form furfuryl alcohol (FAL) and 2,5-bis(hydroxymethyl)furan (BHMF), represents an important research field in upgrading biomass-based furan compounds. Currently, the reduction of furan aldehydes to furan alcohols through chemical transformation often leads to unavoidable environmental issues and the formation of potential byproducts. Biocatalysis has demonstrated expanded applications in converting biomass-derived furan aldehydes into a diverse array of value-added chemicals. This process exhibits significant potential in organic synthesis and biotechnology due to its green and sustainable properties. The biocatalytic reduction of FF and HMF represents an especially important route for the selective synthesis of FAL and BHMF. This review discusses recent progress in the biosynthesis of FAL and BHMF from biomass-derived FF and HMF through biocatalytic processes. Recently discovered enzymes and whole cells used as biocatalysts for the production of furan alcohols are summarized. In addition, chemoenzymatic cascades for synthesizing furan alcohols from biomass hydrolysate and raw biomass materials are also discussed.