Rxi 1ms

Analyses were conducted in a Thermo Ultra GC Trace equipped with a flame ionisation detector and a Thermo DSQ II mass spectrometer (split flow). An Rxi^®—1 ms (60 m × 0.25 mm × 0.25 µm film thickness) column from RESTEK was used. The injector temperature was 280 °C, and the detector temperature (FID) was 300 °C. The MS temperatures were as follows: transfer line, 280 °C and ion source, 220 °C. The scan range operated between 20 U and 250 U (from 2.50 min to 4.90 min) and between 13 U and 250 U (above 4.90 min). The oven was programmed at 50 °C, held for 3 min; then, a 4 °C/min increase ramped the temperature to 310 °C, where it remained for 10 min. The injection quantity was 1 µL with 15 mL/min split for water extract samples, and 0.5 µL with 100 mL/min split for CO₂ extract samples. The carrier gas (He) flow was kept constant at 300 kPa. Based on electron spectra from the NIST 2011 library and the Kovats index, the studied analyte was identified. The volatile compounds were identified.

Essential oils were isolated through hydrodistillation from 5.00-g dry plant-weighted portions using a Clevenger-type apparatus. The makeup of volatile compounds in the oil composition was determined using Thermo Trace GC Ultra/DSQ II (Thermo Fisher Scientific, Waltham, MA, USA). Operating parameters of the gas chromatography were set up as follows: column: nonpolar stationary phase Rxi⁻¹ ms (length 60 m, internal diameter 0.25 mm and, film thickness 0.25 μm; Restek Corp., Bellefonte, PA, USA); injector temperature: 280 °C; FID detector temperature: 300 °C; carrier gas: helium, constant pressure 300 kPa and split ratio 1:100; oven temperature program was 50–300 °C at 4°/min. Mass spectrometry parameters: ion source temperature 200 °C and ionization energy 70 eV. The quantity of the individual components was expressed as a percentage of the essential oil and was achieved using a flame ionization detector connected through the MS-FID splitter (SGE Analytical Science, Ringwood, Melbourne, VIC, Australia). Databases from the NIST Library, Wiley 8th edition and the Adams 4th edition were used.

We performed analysis of oils to evaluate constituents and impurities by diluting with ethanol to 10⁻³, 10⁻⁴, and 10⁻⁵. We injected the diluted oil and analyzed using a 7890B/5977B gas chromatograph/mass spectrometer (GC/MS, Agilent Technologies, Inc., Santa Clara, CA). The column was a Restek (Bellefonte, PA) Rxi®-1ms (0.32 mm I.D., 60 m long, 1.0 μm film thickness) with ultra-high purity helium flowing at 2 mL min⁻¹. The oven program was 58.25 min long and started at 30°C for 5 min, 5°C min⁻¹ to 170°C, 20°C min⁻¹ to 250°C, hold for 10 min, 40°C min⁻¹ to 300°C, hold for 10 min. Electron impact (EI) ionization spectra were collected from m/z 30–500 with an MS source temperature of 300°C and quadrupole temperature of 150°C.

Essential oils were isolated through hydro-distillation from 5.00 g dry plant weighted portions using a Clevenger-type apparatus. The makeup of volatile compounds in the oil composition was determined using Thermo Trace GC Ultra/DSQ II (Thermo Fisher Scientific, Waltham, MA, USA). Operating parameters of the gas chromatography were set up as follows: column—non-polar stationary phase Rxi–1 ms (length 60 m, internal diameter 0.25 mm, film thickness 0.25 μm, Restek Corp., Bellefonte, PA, USA), injector temperature: 280 °C, FID detector temperature: 300 °C, carrier gas—helium, constant pressure 300 kPa and split ratio 1:100, oven temperature program was 50 to 300 °C at 4°/min. Mass spectrometry parameters: ion source temperature 200 °C, ionization energy 70 eV. The quantity of the individual components was expressed as a percentage of the essential oil and was achieved using flame-ionization detector connected through the MS-FID splitter (SGE Analytical Science, Ringwood, Melbourne, VIC, Australia). Databases from the NIST Library, Wiley 8th edition and the Adams 4th edition were used. All samples were tested in triplicates.