Lytic Action of Egg White Lysozyme on the Microorganisms Contaminating Food

There are a lot of papers concerning the lytic action of lysozyme on several strains. Most of these works, however, have been carried out in the biochemical field to clarify the mechanism of lysis by lysozyme, and in these studies, the test strains were generally used for the experiment after being killed by exposing to ultraviolet ray.Since the microorganisms contaminating food generally grow well on food, it seems reasonable that in a study of the lytic action of lysozyme on the microorganisms contaminating food, iiving test strains should be used.A new method for determining the lytic activity of lysozyme on living microorganisms has been developed in our laboratory. By using this method, the lytic action of egg white lysozyme on Proteus vulgaris and Escherichia coli was investigated.According to the results, the lytic activity of egg white lysozyme on these two strains was the highest when. they were treated with 0.05% lysozyme, and this activity became lower in the order treated with 0.025, 0.0125, 0.1, and 0.2% lysozyme.It was also fond that egg white lysozyme exhibited a fairly highem lytic activity on Escherichia coli as compared with that on Proteus vulgaris.