Preparation and Characterization of β-glucosidase Films for Stabilization and Handling in Dry Configurations.

Abstract

AIMS\nTo improve the stability of protein.\n\n\nBACKGROUND\nThe stability of protein is of significance to maintain protein function for therapeutical applications. However, it still remains challenging.\n\n\nOBJECTIVE\nA general method of preserving protein stability and function was developed using gelatin films.\n\n\nMETHOD\nEnzymes immobilized onto films composed of gelatin and ethylene glycol (EG) were developed to study their ability to stabilize proteins. β-glucosidase was selected as a model functional protein. We further assessed the tensile properties, microstructure and crystallization behaviours of the gelatin films.\n\n\nRESULT\nOur results indicated that film configurations can preserve the activity of β-glucosidase under rigour conditions (75% relative humidity and 37°C for 47 days). In both control and films containing 1.8 % β-glucosidase, tensile strength increased with increased EG content, whilst the elongation at break increased initially and then decreased over time. The presence of β-glucosidase had a negligible influence on tensile strength and elongation at break. Scanning electron-microscopy (SEM) revealed that with increasing EG content or decreasing enzyme concentrations, more-dense microstructure was observed.\n\n\nCONCLUSION\nIn conclusion, dry film is a promising candidate to maintain protein stabilization and handling. Other: In addition, the configuration is convenient and cheap, and thus applicable to protein storage and transportation processes in the future.