Recent progress in sustainable biomass valorization via chemoenzymatic catalysis

Abstract

Great concerns over the depletion of non-renewable carbon resources (e.g., petroleum) and the environmental problems (e.g., global warming) caused by overuse of fossil-based resources have been spurring the transition of the current fossil-based economy to a circular bioeconomy. Catalytic biomass valorization is an important strategy toward achieving this. Recently, chemoenzymatic cascades, integrating chemocatalysis with enzyme catalysis in one pot, have emerged as powerful strategies in synthetic chemistry because of the complementary advantages of the two distinct catalytic subdisciplines. The mutual inactivation and incompatibility issues between these two catalytic subdisciplines in terms of operating conditions, such as solvent, pH and temperature, are the major hurdles in the development of such catalytic cascades. In this review, we provide an overview of the impressive developments over the last five years in the synthesis of value-added chemicals, fuels and materials from renewable biomass resources, including carbohydrates, lignin, triglycerides, proteins, terpenes and their derivatives, by chemoenzymatic cascades. The production of high-value products, such as furanics and aromatics from monomers and the depolymerization of recalcitrant polysaccharides and heterogeneous lignin (a key procedure in biorefineries), and their modification and polymerization by chemoenzymatic catalysis are covered. Particularly, the challenges and potential solutions for developing integrated chemoenzymatic processes are critically discussed. Future research perspectives are proposed to facilitate the realization of economic and sustainable biomass conversion processes.