Valorization of residual lignin from corncob residues into thermosensitive lignin-based “molecular glues” for recycling cellulase

The cost of enzymolysis is a major bottleneck for the industrialisation of lignocellulosic enzymatic hydrolysis technology, and recycling cellulase can reduce this cost. Herein, a sulfobetaine prepolymer (CPS) with terminal chlorine was grafted onto enzymatic hydrolysis residual lignin (EHL) from corncob to construct thermosensitive lignin-based “molecular glues” (lignin-based sulfobetaine polymers, L-CPS) that were used to recover and recycle cellulase. L-CPS 2 (1.0 g/L) was added to the corncob residue (CCR) enzymolysis system (50 °C, pH 4.5). After hydrolysis, L-CPS 2 co-precipitated with cellulase through hydrophobic binding when cooling to 25 °C. This co-precipitation decreased the amount of cellulase by 40 %. In summary, a thermally responsive lignin-based molecular glue was constructed for green recycling of cellulase, providing a new approach to decreasing the cost of lignocellulosic enzymolysis and high value utilisation of industrial lignin.