Chemical Composition and Antibacterial Activity of the Essential Oil of Salvia hydrangea from Two Localities of Iran

Background: The genus Salvia L. (Lamiaceae) consists of 58 annual and perennial species in Iran, of which 17 are endemic. S. hydrangea DC. ex Benth. with common Persian name of "Gol-e Arooneh" has been used in folk medicine of Iran as antiinflammatory, antispasmodic, carminative and sedative. Infusion of flowers was used for treating cold in traditional medicine of Fars province. Objective: Study of chemical composition and antibacterial activity of the essential oils of S. hydrangea from two different localities of Iran. Methods: Aerial parts of S. hydrangea were collected in full flowering stage from two different localities Abadeh (Fars province) and Takab (Azarbaijan province). The oils were obtained by hydrodistillation using a Clevenger type apparatus and analyzed by GC and GC-MS instruments. Antibacterial activities of the oils were evaluated by disc diffusion method. MIC values were measured by microdilution broth susceptibility assay. Results: The essential oils yield of Abadeh and Takab were 0.1 and 0.13% (w/w) based on dry weight of plants, respectively. Thirty-seven and 35 compounds were identified in the oil samples which constituted 97.4 and 98.3 % of the total oils, respectively. In the oil obtained from Abadeh, β-caryophyllene (25.2%), 1,8-cineole (15.2%) and caryophyllene oxide (11.1%) were found as the major components. From Takab sample β-caryophyllene (26.2%), 1, 8-cineole (14.2%) and α-pinene (11.2%) were characterized as the main compounds. The oils showed moderate antibacterial activity. Conclusion: The differences observed in essential oil composition of two studied samples could be attributed to their different ecological, geographical and edaphical origin factors. The moderate antibacterial activity of the oils could be associated with the presence of 1, 8-cineole.