Nitrile hydrolyzing enzymes: Immobilization and potential applications

Microbial nitrile converting enzymes may catalyze the hydrolysis of nitriles/amides into corresponding carboxylic acids, leading to industrial applications, including pharmaceuticals, agrochemicals, and fine chemicals. However, using free enzymes in these processes often leads to limitations such as low stability, low efficiency, and high cost. Microbial nitrilases are important enzymes that biotransform nitriles to carboxylic acids or amides, which are important intermediates for synthesizing various industrially essential products. Immobilization of these enzymes is a promising strategy to improve their stability, reusability, and catalytic efficiency, making them more cost-effective for industrial applications. Immobilization methods such as physical adsorption, covalent binding, physical entrapment, and cross-linking have been reported for microbial nitrilases. The immobilization of nitrilases has been applied to produce acrylamide, nicotinamide, mandelic acid, nicotinic acid, and 2-phenyl propionic acid. Using immobilized nitrilases in industrial processes has shown significant advantages, such as increased productivity, reduced operational costs, and improved product quality. This chapter discusses the current state of the art in microbial nitrilase immobilization and its applications for efficiently producing industrially essential value-added products.