Antibacterial properties of certain essential oils against different strains of Staphylococcus aureus

Abstract

Antibiotics introduce very narrow group of substances. On the other hand natural active substances are chemically very diverse [1]. There have been more and more bacteria which are resistant against same type of antibiotics, for example the large problem introduce Methicillin-resistant Staphylococcus aureus (MRSA) in hospitals [2]. The aim of this study was to identify antimicrobial properties of the 7 essential oils (EOs) in vapour phase against 2 collection strains of MSSA, 1 collection strains of MRSA and 6 clinical isolates of S. aureus, obtained from two hospitals. All these strains have been tested against 10 species of antibiotics in standard doses. Tested EOs were obtained by hydro-distillation and tests of their antimicrobial properties were carried out by the modified diffusion method for testing of EOs in vapour phase [3] in concentrations 0.0083–0.53µl/cm3 of air. The ampicillin and erythromycin were tested as reference antibiotics by standard diffusion method in direct contact. The best MICs were shown by Armoracia rusticana (0.0083–0.017µl/cm3), followed by Majorana syriaca (0.0083–0.13µl/cm3) >Allium sativum (0.0083–0.26µl/cm3) >Satureja hortensis (0.017–0.13µl/cm3) >Satureja montana (0.033–0.26µl/cm3) >Thymus vulgaris (0.033–0.26µl/cm3) >Thymus serpyllum (0.033–0.53µl/cm3). Based on the results, EOs mentioned above could be considered as effective anti-Staphylococcal natural products.