Kinetics of the enzymatic hydrolysis of cellulose

Abstract

Hydrolysis of bagasse, avicel and CMC was conducted with a view to developing kinetic models for hydrolysis of cellulose. Hydrolysis of these cellulosic substrates was carried out with Trichoderma reesei cellulase preparation at pH 4.8 and 50 C. Reducing sugar was estimated by Dinitrosalicylic acid method with glucose as standard. Prominent product inhibition in the presence of D-glucose was observed for all the substrates. Percent inhibition in presence of D-glucose was decreased with increasing substrate concentrations. From the kinetic data of enzymatic hydrolysis of cellulose, a competitive inhibition model was obtained for all the three substrates. In the present work the reducing sugar release from hydrolysis and from the model equation were found to be very close to each other. Reducing sugar release by enzymatic hydrolysis varied depending on the nature of substrate. Maximum release was obtained from bagasse followed by avicel and CMC. The model developed in the present work would be useful in the design of a bioconversion reactor for the saccharification of natural cellulosic substrates.