H. B. Naylor

Distribution of lysozyme activity in the exteriors of eggs from Gallus gallus.

Abstract 1. 1. The amount of lysozyme activity in the egg shell exteriors, including cuticle, shell, outer and inner shell membranes was determined. 2. 2. The cuticle, shell and membranes from one dozen eggs were separated and the lysozyme and protein extracted by grinding and by soaking in normal saline (0·.9 % NaCl). 3. 3. The cuticle and shell contained little lysozyme, but the membranes were rich in this enzyme. 4. 4. The amount of activity was dependent on the type of method used for extraction. 5. 5. The outer and inner shell membranes had approximately the same amount of lysozyme per unit of membrane. The presence of salt during the extraction procedure was found to be essential for the detection of lysozyme activity.

The Effect of Egg Position in Storage on Susceptibility to Bacterial Spoilage

Psuedomonas aeruginosa inoculated onto the inner shell membrane at the air cell produced more rapid spoilage in eggs stored normally than in eggs stored with the blunt end down. More extensive growth of bacteria in the former group of eggs was demonstrated by UV candling for fluorescence, bacterial isolations from albumen and bacteriological counts of the shell membranes. Membrane infections tended to be confined to the area of inoculation for at least 6 days. There was no difference in the spoilage rates of eggs inoculated with identical numbers of bacteria on the inner shell membrane or directly in the albumen when eggs were stored with the blunt ends up. When eggs were stored with the air cells down, however, the air cell inoculated eggs required a longer time to spoil than did those eggs icceiving the inoculum in the albumen. The sharp and blunt ends of eggs were contaminated with Pseudomonas aeruginosa and stored in normal and reverse positions. Spoilage was quickest when the infected ends of the eggs were stored upwards.