ABSTRACT
Optimization of cellulose enzymatic hydrolysis is crucial for cost-effective bioethanol production from lignocellulosic biomass. Enzyme immobilization in solid support allows enzyme recycling for reuse, lowering hydrolysis costs. Graphene is a nanomaterial isolated in 2004, which possesses exceptional properties for biomolecule immobilization. This study evaluates the potential for ß-glucosidase recycling by immobilization on graphene nanosheets. Data reported here demonstrated that graphene-immobilized ß-glucosidase can be recycled for at least eight cycles. Immobilization did not change the optimal temperature of catalysis and improved enzymatic stability upon storage. The role of glucose-6-phosphate on immobilized enzyme was also investigated, demonstrating that glucose-6-phosphate acts as a mixed-type activator and improves storage stability of immobilized enzyme. Complete cellulose hydrolysis using graphene-immobilized ß-glucosidase in the presence of glucose-6-phosphate resulted in greatly improved hydrolysis rates, demonstrating the potential of this strategy for biomass hydrolysis.
