Anti-inflammatory and Antibacterial Activity of Rosmarinus officinalis L. Essential Oil and Hydrosol against Methicillin-Resistant Staphylococcus aureus (MRSA)

Rosmarinus officinalis L. (Rosemary) that is recently known as Salvia rosmarinus Spenn endogenously grows in Mediterranean region. The essential oil of rosemary has been demonstrated to have anti-inflammatory, antibacterial, and antioxidant activities. The present study aimed to evaluate the anti-inflammatory and antibacterial activities of the essential oil and hydrosol of R. officinalis against methicillin-resistant staphylococcus aureus (MRSA). The aerial parts of R. officinalis were collected in Altınova, Iskele, North Cyprus and hydro-distillation method was performed using a Clevenger apparatus to obtain the essential oil and the hydrosol. Anti-inflammatory activity of the oil (25-200 μg/ml) was evaluated using the protein denaturation inhibition assay. The antibacterial activity of the oil and the hydrosol was tested against MRSA ATCC 33591 using the well diffusion method. Experiments were carried out in triplicate, and statistical analysis was performed using the chi-square test. The oil showed concentration-dependent anti-inflammatory activity (3.07 ± 0.296% to 32.46 ± 2.229% at 25-200 μg/ml, p<0.05). The essential oil and the hydrosol of R. officinalis had moderate antibacterial activity against MRSA with the inhibition zones of 13.6 ± 1.154 mm and 16.6 ± 1.527 mm, respectively. The anti-inflammatory and antibacterial activities are attributed to the presence of active compounds 1,8-cineole, α-pinene, camphene and camphor. These products may serve as promising alternatives or complements to conventional medicine to combat resistant bacteria.