Cellulase deactivation in a stirred reactor

During the production or downstream processing of an enzyme it is always subjected to shear stress, which may deactivate the enzyme. This susceptibility of enzymes to shear stress is a major concern as it leads to the loss of enzyme activity and is, therefore, a major consideration in the: design of the processes involving enzyme production and its application. In the present work the cellulase enzyme was subjected to shear stress in a stirred reactor with an objective of investigating its deactivation under various conditions such as different agitation speeds, concentrations of enzyme, concentrations of buffer, pH ranges, buffer systems and the presence of gas-liquid interface. It was found that the extent of deactivation depends upon the conditions under which the enzyme was subjected to shear. (C) 2000 Elsevier Science S.A. All rights reserved.