fa تحقيقي Original Paper <div style="margin-left: 1.3pt"> <p><strong>ABSTRACT</strong></p> <p><strong>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Background and Objective</strong>: <em>Lavandula stoechas</em> is a species of native and permanent plants in Golestan province that belongs to the family <em>Lamiaceae</em>. <em>L. stoechas</em>&nbsp;has been used in traditional medicine for treatment of various diseases. The aim of this study was to extract essential oil using steam distillation method from the flowers of <em>L. stoechas</em> collected from Jahan-nama region in the Golestan province, and evaluate its antibacterial activity.</p> <p><strong>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Methods</strong>: Steam distillation (Clevenger) and GC-MS system were used to separate volatile oils and identify the essential oil components, respectively. Two methods of disk diffusion and broth micro dilution were used to evaluate the antimicrobial effect of L<em>. stoechas</em> essential oil. Six bacterial species including <em>Staphylococcus aureus</em>, <em>Bacillus sp., Enterococcus faecalis, Salmonella enteritidis, Escherichia coli</em> and <em>Pseudomonas aeruginosa</em> were tested.</p> <p><strong>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Results</strong>: The essential oil yield was 0.28%. The main components were camphor (71.86%), 1, 8-cineole (4.08%), linalool (3.77%) and borneol (3.19%). The essential oil showed no inhibitory effect on <em>P. aeruginosa</em> and <em>E. faecalis</em>, while it had different inhibitory effects on other bacteria. <em>S. aureus</em> and <em>Bacillus sp</em>. showed the highest sensitivity with inhibition zone diameter of 32 and 29 mm, respectively.</p> <p><strong>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Conclusion:</strong> The results of this study showed that the essential oil of <em>L. stoechas</em> has high inhibitory and antimicrobial activity particularly against Gram-positive bacteria, which may be due to the presence of 71.86% camphor in its composition.</p> <p></p> </div> L. stoechas, essential oil components, camphor, antimicrobial effect. 53 58 http://mlj.goums.ac.ir/browse.php?a_code=A-10-1-406&slc_lang=fa&sid=1 Jila Asghari 100319475328460010795 100319475328460010795 Yes Department of Chemistry Sanaz Sadani 100319475328460010796 100319475328460010796 No Department of Chemistry Ezzatollah Ghaemi 100319475328460010797 100319475328460010797 No Department of Microbilogy Mohsen Mazaheri Tehrani 100319475328460010798 100319475328460010798 No Department of Chemistry