Investigation of stability and activity of alpha-amylase immobilized on nano pore zeolite

Abstract

Introduction: One of the important upsets about enzymes is their short lifetime. Enzymes are sensitive and have less stability .They lose their activity under some condition such as PH changes, high temperature, organic solvents and detergents. Immobilization of enzymes on solid supports follow significant advantages, including reuse, enhanced stability, easy handing, recovery from the reaction Medium. Since the fields of application of α-amylase enzyme are very broad , such as textile design, paper and medical industries, in the present study, we used nano zeolite to immobilize α-amylase. Nano zeolite is stable under high temperature, pH ... and it is also cheap , non toxic, and not harmful to the enzyme. Materials and methods: Firstly , nano zeolite was activated with glutaraldehyde and then αamylase was immobilized on it by Covalent bonding. Average of immobilization measured in 280 nm. This links were seen by TEM microscope. And then we compared activity of free and immobilized α-amylase. Results: In this study, activity of free enzyme is more than immobilized enzyme, but stability of immobilized enzyme is more than free enzyme. Thermal stability of immobilized α-amylase was compared with free enzyme. The results showed that the immobilization process protected the enzyme against heat in activation. The pH stability of α-amylase was determined by incubation at different pH values. The result indicated that there was significant pH stability after immobilization process. Conclusion: The overall performance of immobilized α-amylas indicated that immobilized stability of α-amylase are more than free enzyme and All these criteria can be successfully utilized in practical applications.