Abstract

communis L.) leaves against selected Gram-positive and Gram-negative bacterial strains. The essential oil was obtained using microwave-assisted hydrodistillation, and its chemical composition was analyzed through gas chromatography–mass spectrometry (GC–MS). The analysis revealed a high content of oxygenated monoterpenes, including cineole (26.59%), linalool (14.68%), and α-pinene (13.68%). Antibacterial activity was tested using the agar well diffusion method against four bacterial strains: Escherichia coli and Klebsiella pneumoniae (Gram-negative) and Bacillus subtilis and Micrococcus luteus (Gram-positive). Prior to testing, bacterial suspensions were standardized to an optical density (OD₆₀₀) of 0.06, except for Micrococcus luteus, which was adjusted to 0.13. In each assay, 20 µL of essential oil was applied per well. The essential oil demonstrated the highest antibacterial effect against Bacillus subtilis with a mean inhibition zone of 3.06 cm. Escherichia coli showed a strong response (2.84 cm), while Klebsiella pneumoniae displayed moderate inhibition (1.75 cm). No visible inhibition was observed for Micrococcus luteus. These findings suggest that Myrtus communis essential oil possesses potential antibacterial properties, particularly against certain Gram- positive and Gram-negative bacteria. This highlights its potential as a natural antimicrobial agent for use in veterinary medicine, food preservation, and animal health management