A New Antibacterial Protocol Based on Cymbopogon nardus (L.) Rendle Essential Oil and UV-C Radiation with Potential Application for Hatching Eggs.

Background/

Objectives

Hatching egg sanitization protocols are primarily developed to protect embryos during the embryonic stage from exposure to horizontally transmitted pathogenic bacteria, thereby ensuring their survival. This study aimed to evaluate the antibacterial efficacy of Cymbopogon nardus (L.) Rendle (Poaceae) essential oil, alone or combined with UV-C radiation, as a potential sanitization protocol for hatching eggs.

Methods

Unwashed table eggs, used as an experimental model, were sprayed with C. nardus essential oil at two concentrations (0.625-1.25%) and exposed to UV-C radiation for different exposure times (0-10 min). Mesophilic bacterial load and the physical characteristics of the eggshell were subsequently evaluated.

Results

A significant reduction in the mesophilic bacterial load on the eggshell surface was observed following the application of the treatments. C. nardus essential oil promoted reductions greater than 2 log10 CFU/mL, demonstrating strong antimicrobial activity. The application of UV-C radiation alone resulted in a progressive decrease in the bacterial population, reaching approximately 2 log10 CFU/mL after 10 min of exposure. However, the combination of the essential oil and UV-C radiation showed the highest antibacterial efficacy, reducing bacterial counts to below 1 log10 CFU/mL, indicating that the combination of the two technologies was more effective than either treatment applied alone. No significant macroscopic changes were observed in the physical characteristics of the eggshells.

Conclusions

The combined application of C. nardus essential oil and UV-C radiation on the eggshell surface may represent a promising sanitization protocol with potential application for hatching eggs.