Evaluation of Antimicrobial Activity of Essential Oil of Eshvark (<i>Rhazya stricta</i>) Against Two Strains of <i>Staphylococcus aureus</i> and <i>Listeria monocytogenes</i>

Abstract

Background: Many diseases are often caused by bacteria, including those caused by Staphylococcus aureus and Listeria monocytogenes. Staphylococcus aureus has a hospital infection source and can cause simple skin diseases such as rashes, as well as more severe diseases, such as pneumonia and meningitis. Listeria monocytogenes has an environmental source, such as water, soil and food, and attacks the central nervous system and causes neurological symptoms, even leading to death. Objectives: This study aimed at evaluating antimicrobial effects of ethanol extract and essential oil Eshvark against clinical isolates of S. aureus and L. monocytogenes, which are resistant to antibiotics. Methods: Different strains of S. aureus bacteria were isolated from Bu-Ali hospital of Zahedan, and standard strains of L. monocytogenes (PTCC 1630) were provided as a lyophilized vial in Iranian collection center of fungus and bacteria (Iranian research organization for Science and industry). In this study, the essential oil of Razya stritca was obtained by Clevenger. Then the minimum inhibitory concentrations were investigated to characterize the antibacterial activities of this essential oil. Results: These tests showed that the approximate minimum inhibitory concentration was at concentrations of 5 and 10 mg per milliliter, and the amount of inhibitory concentration for S. aureus was 25/83 and 6/17 while this amount for L. monocytogenes was 5/53 and 1/7, and the minimum bactericidal concentration (MBC) was also at concentrations of 5 and 10 mg per milliliter. Conclusions: This study confirmed the antimicrobial potential of investigated plants and their usefulness in treatment of resistant isolates of S. aureus and L. monocytogenes.