THE EFFECT OF ULTRASOUND ON HEME ENZYMES IN AQUEOUS-SOLUTION

The effect of cavitating 22 kHz ultrasound on aqueous solutions of hyd rogen peroxide-consuming enzymes, catalase and peroxidases, both plant (horseradish peroxidase) and animal (lactoperoxidase) was studied. Ca talase did not undergo inactivation during sonication, whereas activit y of peroxidases decreased with increased duration of sonication. It i s suggested, basing on the absorption spectra, that some conformationa l changes occur in peroxidases upon sonolysis. It is concluded from th e experiments with free radical scavengers that partial enzyme inactiv ation and modification has not a chemical but a mechanical basis.