VALUE-ADDED PRODUCTS FROM COTTONSEED
Location: Commodity Utilization Research
Title: Enzyme-catalyzed modifications of polysaccharides and poly(ethylene glycol)
Submitted to: Polymers
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: June 14, 2012
Publication Date: June 21, 2012
Citation: Cheng, H.N., Gu, Q.-M. 2012. Enzyme-catalyzed modifications of polysaccharides and poly(ethylene glycol). Polymers. (4):1311-1330.
Interpretive Summary: Polysaccharides are found in most agricultural products and residues. In addition to being major food items, polysaccharides are used extensively in industry as thickeners, gelling agents, stabilizers, interfacial agents, flocculants, encapsulants, and other applications. For many these applications, polysaccharides are modified via chemical reactions in order to improve or customize their properties. In recent years, enzymatic reactions have been increasingly used to supplement chemical reactions. In this paper, a review is made of major enzyme-catalyzed modification reactions involving polysaccharides. With these reactions, it is possible to manipulate polysaccharide structures, such as addition of polar, charged, hydrophobic, and reactive functional groups, reduction of polymer molecular weight, or removal of unwanted structural moieties. It is hoped that the information will be useful to future workers interested in using enzymes for the modifications of polymers.
Polysaccharides are used extensively in various industrial applications, such as food, adhesives, coatings, construction, paper, pharmaceuticals, and personal care. Many polysaccharide structures need to be modified in order to improve their end-use properties; these are mostly done through chemical reactions. In the past 20 years many enzyme-catalyzed modifications have been developed to supplement chemical derivatization methods. Typical reactions include enzymatic oxidation, ester formation, amidation, glycosylation, and molecular weight reduction. These reactions are reviewed in this paper, with emphasis placed on the work done by the authors. The polymers covered in this review include cellulosic derivatives, starch, guar, pectin, and poly(ethylene glycol).