Enzymatic modification of wood fibres for activating their ability of self bonding

Objective is the use of phenoloxidases like laccases to activate the surfaces of fibres for making fibreboards without any adhesive. The concept of using lignin-oxidising enzymes for bonding applications is based on the reactivity of phenoxy radicals in the plant cell wall. A problem is that laccase can only oxidise the phenolic constituents of lignin, due to its lower oxidation potential. Therefore the use of appropriate low molecular-mass compounds (so-called mediators), in combination with laccase, makes this enzyme competent for the oxidation of nonphenolic substrates. The oxidised mediator can rely on an oxidation mechanism that is not available to the enzyme.