Inhibition of methicillin-resistant Staphylococcus aureus (MRSA) by essential oils

Ninety-one essential oils, each distilled from a single plant source, and 64 blended essential oils obtained from a commercial source were screened using the disc diffusion assay for inhibitory activity against methicillin-resistant Staphylococcus aureus (MRSA). Of the 91 single essential oils, 78 exhibited zones of inhibition against MRSA, with lemongrass, lemon myrtle, mountain savory, cinnamon and melissa essential oils having the highest levels of inhibition. Of 64 blended essential oils, 52 exhibited inhibitory activity against MRSA, with R.C. (a combination of myrtle, Eucalyptus globulus, Eucalyptus australiana, Eucalyptus radiata, marjoram, pine, cypress, lavender, spruce, peppermint and Eucalyptus citriodora oils), Motivation (a combination of Roman chamomile, ylang ylang, spruce and lavender oils) and Longevity (a combination of frankincense, clove, orange and thyme oils) blended essential oils having the highest inhibitory activity. These results indicate that essential oils alone and in combination can inhibit MRSA in vitro. Application of these results may include the potential use of essential oils as an alternative therapy for various diseases sustained by S. aureus MRSA. Copyright (C) 2008 John Wiley & Sons, Ltd.