The genus Eryngium L. (Apiaceae) with about 250 species is distributed all over the world. In Europe 26 species belong to this genus, while in Serbia five species are described: E. amethystinum L., E. planum L., E. campestre L., E. serbicum Pancic, and E. palmatum Pancic & Vis. [1, 2]. Species of this genus are used in traditional medicine for reproductive problems, against various inflammatory disorders, edema, sinusitis, and snake or scorpion bite [3]. Eryngium palmatum is a Balkan endemic species [1, 2]. Capetanos et al. obtained sesquicineole (21.3%), caryophyllene oxide (16.0%), spathulenol (16.0%), and sabinene (5.5%) as the main components in the essential oil of aerial parts of this plant [4]. The root essential oil of this endemic species and its antimicrobial activity were not previously investigated. Roots of E. palmatum were collected in Sicevacka Gorge, in Eastern Serbia in April 2007. Identification was confirmed by Dr. Marjan Niketic, curator botanist of the Natural History Museum, Belgrade, Serbia, and a herbarium specimen was deposited there (2007040201 BEO). The essential oil was obtained by hydrodistillation from air-dried and grounded herbal material in a Clevenger-type apparatus according to the procedure given in European Pharmacopoeia 7.0 [5]. The yield of the essential oil was calculated on a dry weight basis (w/w) after the evaporation of n-hexane. The root of E. palmatum yielded 0.06% (w/w) of yellow oil. The GC and GC/MS analyses were performed on an Agilent 7890A gas chromatograph equipped with a 5975 C inert XL EI/CI mass selective detector (MSD) and a flame ionization detector (FID). An HP-5MS capillary column (Agilent Technologies, 0.25 mm 30 m, 0.25 m film thickness) was used. GC oven temperature was programmed from 60C to 300C at a rate of 3C/min. Helium was used as carrier gas (constant pressure mode); inlet pressure 20.3 kPa; linear velocity 1 mL/min at 210C. Injector temperature 250C, injection mode split 50:1. Retention time was locked (RTL), lock compound was n-hexadecane with retention time 32.89 min. MS scan conditions: source temperature 230C; interface temperature 280C; EI mass spectra (70 eV) in the m/z range 35–550. The retention indices were experimentally determined using n-alkanes (C 8 –C 20 and C 21 –C 40 ) injected after the essential oil under the same chromatographic conditions. The identification of the compounds was based on the comparison of their retention indices (RI), their retention times (t R ), and mass spectra with those obtained from authentic samples and/or the NIST AMDIS (Automated Mass Spectral Deconvolution and Identification System) software, Wiley libraries, Adams database, and literature [6]. Relative percentages of the identified compounds were computed from the GC-FID peak area. 1 H NMR spectra were recorded on a Bruker Avance III 500 NMR spectrometer (500 MHz in CDCl 3 ) in 5 mm standard tubes. Chemical shifts are given on the scale relative to TMS as internal standard. IR spectrum of the pure essential oil was collected in the transmission mode on a Thermo Scientific Nicolet 6700 FT-IR spectrometer using a KBr capillary film in the Mid-IR range (4000–400 cm –1 ). In the E. palmatum root oil, 21 components were identified, amounting to 98.9% of the total oil (Table 1). The oil was characterized by a high percentage of saturated and unsaturated hydrocarbons (78.9%). Sesquiterpene hydrocarbons represented 13.8% of the total oil. The main components were polyacetylene (Z)-falcarinol (34.9%) and saturated aldehyde octanal (31.7%), followed by -curcumene (5.9%), 2,3,6-trimethyl benzaldehyde (5.4%), and heptanal (4.5%).
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