Design of Nanoemulsions Containing Essential Oil of Artemisia Kopetdaghensis: Investigation of Antioxidant Properties and Antimicrobial Activity on Two Isolates from Clinical Specimens

Introduction: The Artemisia plant is known by its scientific name, which is the exclusive species of Kopeh Daghi in Iran. The present study aimed to design a nanoemulsion of the essential oil of Kopeh Daghi and investigate its antimicrobial activity on the gram-negative bacteria Escherichia coli and the gram-positive bacteria Staphylococcus aureus. Method: At first, the essential oil extraction was performed using a Clevenger. Nanoemulsion was prepared by a spontaneous method using Tween 80 as oil in water. The size of nanoparticles was determined using the dynamic light scattering method. The antioxidant and antibacterial effects of Nanoemulsion at a concentration of 15% of essential oil were investigated. Results: In the current research, 38 compounds were identified in the species of Artemisia kopetdaghensis, of which Davanone, with 28.89%, was the most effective substance. The results of the antioxidant test demonstrated that pure essential oil (IC₅₀= 7.05 mg/ml) and Nanoemulsion containing essential oil (IC₅₀= 46.51 mg/ml) had the highest antioxidant activity, respectively. Furthermore, regarding the inhibition of bacterial growth, Nanoemulsion was the most effective in Staphylococcus aureus with a non-growth zone diameter of 8 mm. In Escherichia coli, pure essential oil was the most effective, with a non-growth zone diameter of 9 mm. Conclusion: In general, the antibacterial properties of 15% nanoemulsion were better compared to 15% essential oil. Moreover, Nanoemulsion containing the medicinal plant essential oil had more antioxidant properties compared to 15% essential oil