Mycosphere essay 10: properties and characteristics of microbial xylanases

Abstract

Xylanases are a group of enzymes that hydrolyze xylan which is a primary constituent of hemicellulose, the second most abundant polysaccharide in nature. These enzymes are endo-beta-1,4-xylanases, they include debranching enzymes such as xylosidases, glucoronidases, arabinofuranosidases and acetylxylan esterase. They are produced by algae, crustaceans, insects, bacteria, fungi and yeasts, with microbial sources being the most commercially important. There are multiple genes for its production, resulting in xylanases with different biochemical characteristics in terms of pH and temperature optimimum, pI and molecular weight. This review describes the importance of xylanases in the hydrolysis of xylan to obtain xylose and xylitol and their applications in pharmaceutical, paper and food industries.