Immobilization and Stabilization of Microbial Lipases

Abstract

Lipases (triacylglycerol acyl hydrolases, E.C. 3.1.1.3) are ubiquitous enzymes that catalyze numerous reactions such as hydrolysis, interesterification, esterification, alcoholysis, acidolysis and aminolysis. Broad substrate specificity and high stereo-, regio- and chemoselectivity make lipases attractive catalysts in a wide range of industrial applications. Lipases are used in the food, pharmaceutical, agrochemical, oleochemical, cosmetic and detergent industries. In spite of their tremendous potential, commercial application of lipases in industry is still limited due to their high cost and relatively low stability. This chapter describes the use of enzyme immobilization as an efficient strategy to overcome these drawbacks. Immobilization of lipases enhances properties such as thermostability and activity, facilitates separation of products and provides more flexibility with enzyme/substrate contact by using various reactor configurations. Numerous methods for lipase immobilization are available. Baring in mind the scope of this book, the most common methods, including adsorption, cross-linking, adsorption followed by cross-linking, multipoint covalent attachment and physical entrapment will be discussed in detail. Advantages and disadvantages of commonly used immobilization methods and the design and selection of immobilization strategies are analyzed as well. Particular emphasis is placed on the most recent advances in the development of an efficient lipase immobilization system that would enable us to achieve the desired benefits. This chapter will also highlight benefits of immobilization in lipase stabilization, with respect to other employed methods such as chemical modification and recombinant DNA technology.