RELATING THE MICROSTRUCTURE OF ENZYME DISPERSIONS IN ORGANIC-SOLVENTSTO THEIR KINETIC-BEHAVIOR

The effect of ultrasound irradiation on activity and particle size of a subtilisin-catalyzed interesterification reaction in an organic solv ent was studied. Across a range of levels of water addition and irradi ation amplitude, sonication failed to increase reaction rate compared with stirred systems. Sonication was shown to be effective in reducing particle size, but the effect of any reduction in diffusional limitat ions on reaction rare was exceeded by an inhibitory effect of the trea tment. This inhibition was found to be irreversible upon cessation of sonication and aqueous assay of activity, or recycling of the enzyme i nto a stirred reaction system. (C) 1998 Elsevier Science Inc.