The chemical composition of Salvia euphratica Montbret & Aucher ex Benth. essential oil from Sivas-Turkey

Abstract

Previously, only the fatty-oil composition of Salvia euphratica Montbret & Aucher ex Benth. (syn. Salvia euphratica var. euphratica) was reported, however, there are no other studies on the chemistry of this species [1]. Up to now, there are no reports on the essential-oil composition of this taxon. In this study, we aimed to investigate the composition of three different samples of the essential oil of S. euphratica collected in June 2017 from two different sites in Sivas-Turkey. The essential oil was obtained by hydrodistillation from air-dried aerial parts of the plant using a Clevenger-type apparatus for the duration of 3 h. The essential-oil yields for the three samples were determined to be: 0.25, 0.15, and 0.13% (v/v), for a sample with glandular hairs (1) and a sample without glandular hairs (2) from location 1 and for a sample with glandular hairs (3) from location 2, respectively. The oils were diluted with n-hexane 1:10 (v/v) and analyzed as such on an Agilent 5977 MSD GC-MS system operating in the EI mode injector and MS transfer line temperatures were set at 250 °C. Splitless injection was used in the analysis. Innowax FSC column (60 m x 0.25 mm, 0.25 µm film thickness) and helium, as the carrier gas (1 mL/min), were used in GC-MS analyses. The oven temperature program was: 60 °C for 10 min and then raised to 220 °C at a rate of 4 °C/min, afterwards the temperature was kept constant at 220 °C for 10 min and then raised to 240 °C at a rate of 1 °C/min. Mass spectra were recorded at 70 eV with the mass range m/z 35-425. Relative amounts of the separated compounds were calculated from the integration of the peaks in MS chromatograms. The main components of sample 1 essential oil were 1,8-cineole (20.7%), camphor (10.0%), nopinone (4.7%), trans-pinocarveol (4.3%), myrtenal (4.3%), β-pinene (3.3%), and camphene (2.2%). Sample 2 oil contained high amounts of 1,8-cineole (13.5%), camphor (7.6%), trans-pinocarveol (7.1%), myrtenal (5.7%), nopinone (4.6%), myrtenol (3.9%), borneol (3.4%), and pinocarvone (3.2%). Finally, the main components of sample 3 oil were: 1,8-cineole (16.8%), trans-pinocarveol (4.7%), camphor (4.0%), myrtenyl acetate (3.7%), myrtenal (3.6%), linalool (2.8%), trans-linalool oxide (furanoid) (2.6%), and myrtenol (2.6%). The highest noted AChE-inhibitory activity of the oils were 63±5%, 57±2%, and 63±1%, respectively.