Anti-inflammatory and Antioxidant Activity of Rosemary Essential Oil

Abstract

Background: Rosmarinus officinalis L. (rosemary) is a widely used perennial shrub with diverse culinary and therapeutic applications, particularly in traditional medicine. Its essential oil (EO) has been studied extensively for its pharmacological properties, including antioxidant and anti-inflammatory effects. Methods: This research extracted rosemary EO from plants collected in Rawa, Iraq, in March 2023, utilizing steam distillation. Gas chromatography-mass spectrometry (GC-MS) was employed to analyze the EO's phytochemical composition. Anti-inflammatory properties were assessed using a protein denaturation assay, while antioxidant activity was evaluated through a modified ferric reducing antioxidant power (FRAP) assay. Statistical analysis was conducted using ANOVA and Tukey tests. Results: The GC-MS study identified eucalyptol (34.25%), α-pinene (20.98%), and camphor (13.75%) as the essential oil's primary volatile components. GC-MS analysis revealed 24 components in rosemary EO, with monoterpenes dominating (94.88%). Major constituents included α-pinene, camphor, and eucalyptol. The protein denaturation assay demonstrated significant inhibition of protein breakdown by rosemary EO, indicating anti-inflammatory potential. Moreover, the EO exhibited considerable antioxidant activity, comparable to the positive control Trolox, attributed to its high concentration of α-pinene. The rosemary essential oil showed high antioxidant properties and the inhibition rate of free radicals was 87.45%. It also showed acceptable anti-inflammatory activity at 50 mg/mL compared with diclofenac sodium. Conclusion: Rosemary EO showed promising antioxidant and anti-inflammatory properties, likely attributable to its chemical composition. Our findings showed that rosemary essential oils were safe and have positive biological effects. As a result, they could function as health-promoting components in the medical sector.