Topochemical Design of Cellulose-Based Carriers for Immobilization of Endoxylanase

De Wever, Pieter [Chemical and Biochemical Reactor Engineering and Safety Section, Department of Chemical engineering, KU Leuven, 3001 Leuven, Belgium] De Schepper, Charlotte [Laboratory of Food Chemistry and Biochemistry & Leuven Food Science and Nutrition Research Centre (LFoRCe), Department of Microbial and Molecular Systems, KU Leuven, 3001 Leuven, Belgium] Poleunis, Claude [UCL] Delcorte, Arnaud [UCL] Courtin, Christophe M. [Laboratory of Food Chemistry and Biochemistry & Leuven Food Science and Nutrition Research Centre (LFoRCe), Department of Microbial and Molecular Systems, KU Leuven, 3001 Leuven, Belgium] Fardim, Pedro [Chemical and Biochemical Reactor Engineering and Safety Section, Department of Chemical engineering, KU Leuven, 3001 Leuven, Belgium]

Xylooligosaccharides (XOSs) gained much attention for their use in food and animal feed, attributed to their prebiotic function. These short-chained carbohydrates can be enzymatically produced from xylan, one of the most prevalent forms of hemicellulose. In this work, endo-1,4-β-xylanase from Thermotoga maritima was immobilized on cellulose-based beads with the goal of producing xylooligosaccharides with degrees of polymerization (DPs) in the range of 4−6 monomeric units. More specifically, the impact of different spacer arms, tethers connecting the enzyme with the particle, on the expressed enzymatic activity and oligosaccharide yield was investigated. After surface functionalization of the cellulose beads, the presence of amines was confirmed with time of flight secondary ion mass spectrometry (TOF-SIMS), and the influence of different spacer arms on xylanase activity was established. Furthermore, XOSs (DPs 2−6) with up to 58.27 mg/g xylan were obtained, which were greatly enriched in longer oligosaccharides. Approximately 80% of these XOSs displayed DPs between 4 and 6. These findings highlight the importance of topochemical engineering of carriers to influence enzyme activity, and the work puts forward an enzymatic system focusing on the production of longer xylooligosaccharides