Activity of essential oils of three Micromeria species (Lamiaceae) against micromycetes and bacteria.

The chemical composition of essential oils from three Micromeria species: M. dalmatica Benth., M. albanica (Griceb. ex K. Mal) Silić and M. thymifolia (Scop.) Fritsch were investigated by GC and GC-MS and their antibacterial and antifungal activities against seven fungal and six bacterial species were evaluated. Biological assays showed strong fungitoxicity of oils from all three Micromeria spp., particularly M. albanica, against all fungi tested. Essential oils of these species also exerted antibacterial effect against Streptococcus aureus, Escherichia coli, Bacillus subtilis and Micrococcus luteus at low concentrations. Higher concentrations of essential oil of M. albanica and M. dalmatica were active against Gram-negative Pseudomonas aeruginosa, which could be due to the high content of piperitenone oxide.