Imobilização de β-glicosidase do fungo Thermoascus aurantiacus por ligação covalente em matriz orgânica de quitosana e alginato

Abstract

The enzyme extract from the solid-state culture of Thermoascus aurantiacus was immobilized on sodium alginate and chitosan beads by the covalent binding technique, focusing on the analysis of the action of β-glucosidase from the fungus T. aurantiacus. The activity of the native and immobilized enzyme was measured at different temperatures, pH levels and ethanol concentrations. The optimum pH of the free enzyme was 4.0, while its immobilized form presented an optimum pH of 3.0, thus supporting a more acidic environment. The immobilized enzyme showed greater stability in the presence of ethanol compared to the free enzyme, retaining 50% of its catalytic activity in 15% ethanol. The immobilized enzyme retained 50% of its activity after 4 cycles. The results obtained in the study demonstrate that the immobilization technique can make the enzyme more robust for some industrial parameters.