Recent applications of ionic liquids in biocatalysis

Biocatalysis is an important area in the context of green chemistry and sustainable development, competing with traditional chemical catalytic processes. However, to be a sustainable bioprocess, the proper choice of the reaction medium plays a significant role, combined with better performance and reduced costs. Volatile organic solvents are commonly used as solvents or cosolvents in certain enzymatic reactions that need to be performed in hydrophobic media. Within biocatalysis, ionic liquids have emerged as promising alternative solvents, particularly to replace less benign organic solvents in nonaqueous reactions, and have been widely investigated over recent decades. In addition, ionic liquids have been used as surface modifiers of solid materials to act as supports of biocatalysts in order to improve the catalytic performance. This chapter provides an overview and outlook of the recent and emerging applications of ionic liquids in nonaqueous media biocatalysis, with emphasis on the pretreatment of biomass, lignin valorization, biofuels production, biosensors, and bioremediation. Final considerations and challenges in this field are also provided.