Composition and antibacterial activity of Achillea clypeolata essential oil

Volatile oil of wild growing population of Achillea clypeolata Sibth. et Sm. (Asteraceae) was studied for yield, composition and antibacterial activity. Eighteen identified components constituted 89.8% of the oil. The major components in the oil were (E)-gamma-bisabolene (17.9%), 1,8-cineol (16.0%), borneol (11.9%) and caryophyllene-oxide (11.5%), together reaching 57.3% of the total oil content. In an antibacterial diffusion assay, the oil showed activity against all tested Gram-negative bacteria (Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa) and Gram-positive Staphylococcus aureus. Copyright (c) 2004 John Wiley & Sons, Ltd.