title: Susceptibility of methicillin-resistant staphylococci to oregano essential oil, carvacrol and thymol.
abstract: The aim of this study was to evaluate the susceptibility of methicillin-susceptible and methicillin-resistant staphylococci (MSS, MRS) to oregano essential oil, carvacrol and thymol. The commercial aerial parts of Origanum vulgare L. were hydrodistilled and the essential oil analysed by gas- chromatography/electron impact mass spectrometry. The inhibition efficacy of this essence and its major components was assayed against 26 MSS and 21 MRS, using an agar dilution method. The methicillin resistance was thoroughly typed by Epsilometer test (E-test), polymerase chain reaction for mecA gene detection and PBP2' latex agglutination test. The results clearly demonstrated that the comparison between the susceptibility of MSS and MRS to oregano oil, carvacrol and thymol showed no significant differences (Fisher's exact test, P > 0.05). The best minimum inhibitory concentration values were reported for carvacrol (0.015-0.03%, v/v) followed by thymol (0.03-0.06%, v/v) and oregano oil (0.06-0.125%, v/v).
authors.affiliation: Dipartimento Farmaco-Biologico, Sezione Microbiologia, Facoltà di Farmacia, Università di Messina, Villaggio Annunziata, 98168 Messina, Italy. atnostro@pharma.unime.it
authors.forename: Antonia
authors.initials: A
authors.lastname: Nostro
authors.forename: Anna R
authors.initials: AR
authors.lastname: Blanco
authors.forename: Maria A
authors.initials: MA
authors.lastname: Cannatelli
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Enea
authors.forename: Guido
authors.initials: G
authors.lastname: Flamini
authors.forename: Ivano
authors.initials: I
authors.lastname: Morelli
authors.forename: Andrea
authors.initials: A
authors.lastname: Sudano Roccaro
authors.forename: Vittorio
authors.initials: V
authors.lastname: Alonzo
mesh_terms: D000890:Anti-Infective Agents / Q000494:pharmacology*; D000081007:Cymenes; D006801:Humans; D008712:Methicillin / Q000494:pharmacology; D016106:Methicillin Resistance / Q000235:genetics; D008826:Microbial Sensitivity Tests; D039821:Monoterpenes / Q000494:pharmacology*; D009822:Oils, Volatile / Q000494:pharmacology*; D031341:Origanum / Q000737:chemistry*; D013210:Staphylococcus / Q000187:drug effects*; D013943:Thymol / Q000494:pharmacology*
chemical_list: D000890:Anti-Infective Agents; D000081007:Cymenes; D039821:Monoterpenes; D009822:Oils, Volatile; D013943:Thymol; C073316:carvacrol; D008712:Methicillin