From fundamentals to valorization: Enzymatic oxidation of cellulosic fibres and underlying mechanisms

Today, a new set of enzymes are ready to be explored. Lytic Polysaccharide Monooxygenases (LPMOs) are a novel versatile type of carbohydrate-modifying enzymes, which were discovered in 2010 (Vaaje-Kolstad et al., 2010). Most of application-oriented research on LPMOs has focused on lignocellulose saccharification, in which LPMOs greatly enhance hydrolytic efficiency in synergy with hydrolases. In contrast, LPMO research on fibre modification has just begun. LPMOs are active on both amorphous and crystalline regions of celluloses, and importantly, introduces new functional groups at the cleavage site through an oxidative mechanism. These new functional groups can be expected to modify surface structure and integrity of pulp fibres, alter water binding properties and charge, and allow for fibre functionalization through site specific chemical modifications. We aim to study LPMO induced modification on cellulosic materials in the present state-of-the-art project. We will examine the possibilities of LPMOs to open, rearrange and modify structurally different celluloses in combination with existing knowledge in enzymatic fibre refining, and investigate functionalization of cellulosic fibres with new reactive chemical groups. Based on these studies, we will propose industrial applications in close collaboration with the project industrial partners; Borregaard, MetsäFibre, UPM-Kymmene Corporation, Essity GHC R&D Tissue, Acticell GmbH, and Novozymes.