The Anti-Bacterial Activity of Egg-White.

The utilization of egg-white as pabulum by bacteria is a fact of common experience. Egg-white also possesses marked anti-bacterial properties for certain bacteria. This phenomena was investigated in the work reported here.

Egg-white was removed aseptically from fresh store eggs with a sterile syringe and serially diluted with meat-infusion broth pH 7.5 to 7.6. One cc. quantities of these dilutions were distributed into separate sterile small (Wassermann) test tubes and each tube, including a control tube of broth, was inoculated and well mixed with 0.1 cc. of a 24-hour broth culture of the organisms used. Similar series were made with inocula of 0.1 cc. of a 1-100 and 0.1 cc. of a 1-10,000 dilution in broth of the broth cultures. All tubes were incubated for 20 to 24 hours and then observed for inhibition of growth. In addition, loopfuls of the mixture from each tube were separately streaked out on agar plates (blood agar for streptococcus) which were incubated for 24 hours and then examined for growth. Absence of growth in the streaks on the agar plates was assumed to indicate sterilization of the inocula in the corresponding tubes.