Immobilization of Xylanase Using a Protein-Inorganic Hybrid System

Abstract

In this study, the immobilization of xylanase using a protein-inorganic hybrid nanoflower system was assessed to improve the enzyme properties. The synthesis of hybrid xylanase nanoflowers was very effective at 4°C for 72 h, using 0.25 mg/ml protein, and efficient immobilization of xylanase was observed, with a maximum encapsulation yield and relative activity of 78.5% and 148%, respectively. Immobilized xylanase showed high residual activity at broad pH and temperature ranges. Using birchwood xylan as a substrate, the V_max and K_m values of xylanase nanoflowers were 1.60 mg/ml and 455 μmol/min/mg protein, compared with 1.42 mg/ml and 300 μmol/min/mg protein, respectively, for the free enzyme. After 5 and 10 cycles of reuse, the xylanase nanoflowers retained 87.5% and 75.8% residual activity, respectively. These results demonstrate that xylanase immobilization using a protein-inorganic hybrid nanoflower system is an effective approach for its potential biotechnological applications.

Keywords: Immobilization; Thermomyces lanuginosus; encapsulation; protein-inorganic hybrid; reusability; xylanase.