Chemical Composition and Anti-MRSAActivity of Essential Oil and Ethanol Extract of Lavandula multifida L. from Algeria

International audience ; This work reports for the first time the anti-MRSA activity of the essential oil and ethanol extract of Lavandula multifida L. on clinical and reference strains of methicillin-resistant Staphylococcus aureus (MRSA). Hospitalized patients with infected wounds at the University Hospital of Tlemcen constitute the source of collection for different clinical isolates used in this study. The oils of fresh samples were obtained by hydrodistillation at three developmental stages (before inflorescence, full-inflorescence and afterinflorescence). The oils from the aerial parts of L. multifida were analyzed at three developmental stages. Oil yield was found to vary depending on the stage of development and the highest content of oil (0.2% w/w) was obtained at full-inflorescence. The chemical composition of essential oils studied by GC and GC-MS showed that the main components were carvacrol (from 27.5 to 57%), β-bisabolene (from 25.2 to 38.4%) and caryophyllene oxide (from 3.5 to 7.5%). The Anti-MRSA activity of L. multifida essential oil and ethanol extract was tested by using disc diffusion method and microtiter plates perform for determining their minimum inhibitory concentration (MIC) values. We found a good anti-MRSA activity of L. multifida essential oil since the inhibition diameters reached 27 mm and MICs were lower than 0.1 μl/ml, whereas the ethanol extract was less active. These results seem to be interesting for applications of L. multifida essential oil to fight against MRSA.