In situ immobilization multi-enzyme biocatalytic system on covalent organic frameworks for efficient conversion of lignocellulose to glucose

Abstract

Efficient enzyme immobilization is crucial for addressing the resource utilization challenges associated with lignocellulose. However, the widespread application of immobilized enzyme systems faces significant obstacles, including low enzyme activity and the limited pore structure of existing carriers. To overcome these challenges, a novel multi-enzyme biocatalytic system (multi-enzymes@COF) was developed for the in situ immobilization of cellulose and β-glucosidase on covalent organic frameworks (COFs). Results showed that multi-enzyme@COF exhibits good crystallinity and a mesoporous structure, leading to an increased enzyme loading rate of 0.6 g/g and enhanced cellulose conversion efficiency of up to 78.7 %. Additionally, multi-enzymes@COF demonstrated remarkable stability a broader pH range (4−7) and temperature range (50–70 ℃), with the actively above 70 %. Moreover, the enzymes maintained approximately 74.7 % of their activity even after seven cycles. This research presents an innovative strategy for the effective utilization of lignocellulose through enzymatic processes, promoting sustainable and efficient resource utilization.