Adsorption Studies of Cellulase and β-glucosidase in hydrothermal pretreated sugarcane bagasse during enzymatic hydrolysis
Moreira Neto, J1; Machado, D. L1; da Costa, A.C1
1 – School of chemical Engineering, State University of Campinas, Brazil.
Production of second-generation biofuels from low-cost lignocellulosic biomass is viewed as a potential alternative to our current reliance on fossil fuels. In Brazil, sugarcane bagasse represents an attractive material for this process, being an agro-industrial waste widely available. Enzyme adsorptions, including productive and non-productive adsorptions, are important factors affecting the rate and glucose yield of enzymatic hydrolysis of lignocellulosic biomass. The Langmuir isotherm has been widely used for calculating the adsorbed amount of enzyme because it represents a simple mechanistic model that can be used to compare kinetic properties of various systems cellulose-cellulase. The adsorption characteristics can depend on the type of substrate used, and since the characteristics of the substrate can change with conversion, it is important to validate the model against a measured amount of adsorbed cellulose during the hydrolysis. The objective of this study is to investigate the influence of the hydrolysis time on the Langmuir isotherm parameters of cellulase and β-glucosidase in the hydrothermal pretreated sugarcane bagasse. All adsorption experiments were performed using two commercial enzyme preparations, cellulase from Trichoderma reesei (Sigma-Aldrich, ATCC 26 921) and β-glucosidase from Aspergillus niger (Novozym 188). The enzyme amounts in the adsorption experiments were quantified by protein measurement using Bradford assay.