Polyester fabric modification by chemical treatment to enhancing the β-glucosidase immobilization.

This work reports the first approach to immobilizing the β-glucosidase enzyme on a modified polyester fabric support matrix. Herein, polyester fabric was successfully fabricated with hydrazide groups incorporated with graphene oxide, followed by glyoxal as the crosslinker. Various techniques, including Fourier transform infrared spectroscopy, scanning electron microscopy, thermogravimetric analysis, differential scanning calorimeter, and zeta potential analysis, were used to investigate their microstructural, dispersive, thermal, and physicochemical properties. β-glucosidase immobilization exhibited maximum activity at pH 6.0 with an immobilization yield (89.5%), immobilization efficiency (92%), and enzyme activity yields (82.3%). After fifteen reaction cycles, the remaining enzyme activity was 59%. Stored at 4 °C, immobilized β-glucosidase retained 74% of its activity, compared to a retain of 43% for soluble β-glucosidase, during the 6-weeks period. Soluble and immobilized enzyme exhibited similar optimal catalytic temperature at 60 °C, while the optimal catalytic pH was 5 and 6, respectively. Both soluble and immobilized β-glucosidase presented Michaelis-Menten kinetics with Vmax values of 1.82 and 2.94 U/mg, and Km values of 2.94 and 5.15 mM, respectively. This research provided a potential directed immobilization method for β-glucosidase, and robust biocatalyst for industrial applications.