The effect of ultrasound on heme enzymes in aqueous solution

The effect of cavitating 22 kHz ultrasound on aqueous solutions of hydrogen peroxide-consuming enzymes, catalase and peroxidases, both plant (horseradish peroxidase) and animal (lactoperoxidase) was studied. Catalase did not undergo inactivation during sonication, whereas activity of peroxidases decreased with increased duration of sonication. It is suggested, basing on the absorption spectra, that some conformational changes occur in peroxidases upon sonolysis. It is concluded from the experiments with free radical scavengers that partial enzyme inactivation and modification has not a chemical but a mechanical basis.