Microbial xylanases and their industrial applications: a review

Despite an increased knowledge of microbial xylanolytic systems in the past few years, further studies are required to achieve a complete understandin g of the mechanism of xylan degradation by microorganisms and their enzymes . The enzyme system used by microbes for the metabolism of xylan is the mos t important tool for investigating the use of the second most abundant poly saccharide (xylan) in nature. Recent studies on microbial xylanolytic syste ms have generally focussed on induction of enzyme production under differen t conditions, purification, characterization, molecular cloning and express ion, and use of enzyme predominantly for pulp bleaching. Rationale approach es to achieve these goals require a detailed knowledge of the regulatory me chanism governing enzyme production. This review will focus on complex xyla n structure and the microbial enzyme complex involved in its complete break down, studies on xylanase regulation and production and their potential ind ustrial applications, with special reference to biobleaching.