How Is Effective Enantioselectivity of Immobilized Enzyme in Kinetic Resolution of Racemate Affected in a Fixed-Bed Reactor?

The purpose of this theoretical discussion is to help researchers understand how some parameters and reaction type (first-order and Michaelis-Menten kinetic) could impact effective enantioselectivity of enzyme in a fixed-bed reactor, including adsorption equilibrium constant (adsorption effect), Biot number, Peclet number, and bed length parameter. The theoretical analysis clearly derives that reaction rate is able to impact the effective enantioselectivity of enzyme through controlling the loading of enzyme on the solid support. In addition, adsorption phenomenon and reaction type have no effect on the effective enantioselectivity in a fixed-bed reactor. Among these parameters, Bi (< 10) shows significant effect on the effective enantioselectivity, which indicates that external mass transfer limitation must be controlled. The interesting analysis suggests that cross-link enzyme aggregates without carrier could be an optional way to overcome mass transfer limitation for immobilized enzyme, and if solid support is applied, adsorption method, which is able to facilitate substrates to contact with enzyme compared to other immobilization methods, could be the best choice to immobilize enzyme when the kinetic resolution of racemate is conducted in a fixed-bed reactor.