Adsorption and kinetic behavior of recombinant multifunctional xylanase in hydrolysis of pineapple stem and bagasse and their hemicellulose for Xylo-oligosaccharide production

A recombinant multifunctional xylanase (RMFXase) was utilized to hydrolyze xylan in pineapple stems and bagasse. The feasibility of using RMFXase and the two agricultural by-products for producing Xylo-oligosaccharides was demonstrated. Adsorption dynamics showed that lignin and cellulose delayed the adsorption equilibrium. The adsorption data fit the Langmuir-type adsorption isotherm. The extent of hydrolysis was quantified by measuring the reducing and total sugars in substrate-RMFXase complexes at 50 degrees C. The substrates had similar hydrolysis characteristics. Differences in the maximum hydrolysis rate (HR) and the time of maximum were obtained. The HRmax of water-insoluble oat spelt xylan reached 55.26% after 2 h. Analysis of the end-products using high-performance liquid chromatography indicated xylobiose and xylotriose were the major hydrolysis products, and the final degree of polymerization was greater than two. The purity of the substrates and RMFXase are the key factors that determine the processing parameters of Xylo-oligosaccharide production. (C) 2012 Elsevier Ltd. All rights reserved.