Enzymatic Degradation of Lignocellulose for Synthesis of Biofuels and Other Value-Added Products

Abstract

Wood is a renewable source for biofuels and chemicals. An efficient pretreatment is required to destroy the highly ordered and complex structure of wood fibres and to improve their enzymatic degradability. To understand the effectiveness of pretreatment on enzymatic degradability, high-throughput analysis of cellulose kinetics using insoluble cellulosic substrate is required. The BioLector technology enables online monitoring of scattered light intensity and fluorescence signals during the continuous shaking of cellulose samples in microtiter plates. It is used to monitor the hydrolysis of three different cellulosic substrates catalysed by a commercial cellulase preparation from Trichoderma reesei (Celluclast). Moreover, the reduction of crystallinity and particle size is a key determining factor for an efficient hydrolysis of cellulose particles in heterogeneous system. To increase the sugar release, crystallinity and particle size were decreased by the dissolution of spruce wood in the ionic liquid EMIM Ac resulting in high conversion and reaction rates. Additionally, the enzymatic action on lignin model substrates is characterised using an activity assay and cyclic voltammetry.