Chemical composition of Rosmarinus officinalis essential oil and antioxidant action against gastric damage induced by absolute ethanol in the rat

Objective: To evaluate the antioxidant activity of the essential oil obtained from Rosmarinus officinalis(R. officinalis) in ethanol-induced gastric ulcer model in vivo.Methods: The antioxidant properties of the essential oil obtained from R. officinalis were evaluated against gastric injury induced by absolute ethanol. Gastric tissues were prepared to enzymatic assays. The levels of glutathione, lipid peroxides, and the activities of glutathione peroxidase, superoxide dismutase and myeloperoxidase were measured.Results: Ethanol produced severe hemorrhagic lesions in the stomach with ulcerative lesion of(140.2 ± 37.2) mm2. In animals pretreated with essential oil of R. officinalis(50 mg/kg, p.o.), a significant inhibition of mucosal injury of(21.2 ± 7.1) mm2(84%inhibition) was observed. The essential oil of R. officinalis protected the gastric mucosa probably by modulating the activities of the enzymes(superoxide dismutase and glutathione peroxidase) and increasing or maintaining the levels of glutathione. In addition,lipid peroxides levels were reduced. The essential oil of R. officinalis was analyzed by gas chromatography–mass spectrometer and the main constituents were cineole(28.5%),camphor(27.7%) and alpha-pinene(21.3%).Conclusions: We suggest that the monoterpenes present in the essential oil obtained from R. officinalis may be among the active principles responsible for the antioxidant activity shown by essential oil of R. officinalis.