Kinetic model for oligosaccharide hydrolysis using suspended and immobilized enzymes

A novel kinetic model that describes the hydrolysis of oligosaccharide using the suspended enzyme has been constructed by introducing the selectivity of the enzyme for cleaving each α-1,6 glycosidic bond of the substrate. The Michaelis-Menten type kinetic constants, K_m and V_max, and the selectivity coefficient, α, are estimated by fitting the model with the experimental data obtained under various conditions. The new constant, α, is estimated at 0.411, and almost the same as the experimental values. The model has been extended for the immobilized enzyme system by taking into account the intraparticle mass transfer resistance. The model constants are estimated similarly to the case of the suspended enzyme system. α^imm (α for the immobilized enzyme system) is a little higher than that in the suspended enzyme system. K_m^imm and V_max^imm, are much greater than those for the suspended enzyme system. The estimated values of the effective diffusivities in the support particle are a few order of magnitude smaller than those in aqueous solution. The model well simulates both experimental results obtained in the suspended and immobilized enzyme systems.