Catalytic and antimicrobial properties of α-amylase immobilised on the surface of metal oxide nanoparticles

Abstract

New methods of obtaining products containing enzymes reduce the costs associated with obtaining them, increase the efficiency of processes and stabilize the created biocatalytic systems. In the study a catalytic system containing the enzyme α-amylase immobilized on ZnO nanoparticle and Fe3O4 nanoparticles was created. The efficiency of the processes was obtained with variables: concentrations of enzymes, temperatures and times, to define the best conditions for running the process, for which were determined equilibrium and kinetics of adsorption. The most effective parameters of α-amylase immobilization on metal oxides were determined, obtaining 100.8 mg/g sorption capacity for ZnO and 102.9 mg/g for Fe3O4 nanoparticles. Base on the best parameters, ZnO-α-amylase was investigated as an antimicrobial agent and Fe3O4-α-amylase was tested as a catalyst in the process of starch hydrolysis. As a result of the conducted experiments, it was found that α-amylase immobilized on Fe3O4 nanoparticles maintained high catalytic activity (the reaction rate constant KM = 0.7799 [g/dm3] and the maximum reaction rate Vmax = 8.660 [g/(dm3min)]).