Gc ms 7890a

Volatile compounds extracted using solid-phase microextraction (SPME) fibers (DVB/CAR/PDMS, 50/30 µM, Supelco-57329-U) were analyzed using a gas chromatography-mass spectrometer (GC/MS 7890A, Agilent Technologies, SC, USA) with an autosampler (Multi-Purpose Sample with DHS option, MPS, Gerstel, Germany). All samples were placed in a 10 mL, sealed with an aluminum cap, and then absorbed onto polydimethylsiloxane (PDMS) fiber at 100 rpm for 30 min at 50 °C. The SPME fiber, which extracted the volatile compounds, was automatically injected into a gas chromatography-mass spectrometer (GC/MS) injection port, and the volatile compounds were thermally desorbed at 250 °C for 3 min and analyzed using GC/MS. Electron impact ionization (70 eV) was performed at a full scan range of 50–550 m/z. The volatile compound was identified based on a mass spectral library (WILEY 10N). The operational conditions for GS/MS analysis are shown in (Table 2).

The GC-MS 7890A and 5975C VL MSD (Agilent technologies, Santa Clara, CA, USA) systems were chosen to analyze the fenugreek extract. The extract (100 µL) was mixed with the water-ethyl-acetate mixture (250 µL) through forceful shaking to gather and concentrate the sample’s top layer. Additions of trimethylchlorosilane and trifluoroacetamide were made, followed by (BSTFA-99 µL + TMCS- µL), and finally, 10 µL of pyridine was added. The mixture was heated for 30 min at 60 °C and the samples were transferred to GC vials. The samples were dried using liquid nitrogen before being dissolved in methanol and analyzed by GCMS. The dried sample was dissolved in HPLC-grade methanol. The sample (1 µL) was injected using an Agilent capillary column (DB5MS) with dimensions of 30 mm, 0.25 mm internal diameter, and a film thickness of 0.25 microns. A temperature of 270 °C and a pressure of 80 kPa was maintained in the injector. Using helium as a carrier gas, the GC procedure was completed in 25 min. The NIST mass spectral database and the collected mass spectra were used to identify the compounds.

100 mg shoot and callus of J. procera were lyophilized before placed in a pestle mortar and ground in 20 ml of 25 mM potassium phosphate buffer, with a pH of 7.0. The homogenate was transferred in a 100 ml conical flask and was shaken for 30 min at room temperature. Then, 20 ml of ethyl acetate was added, the mixture was incubated at room temperature for 5 min. Then, organic and aqueous phases were separated by centrifugation at 5000 rpm for 5 min. The organic phase was collected and evaporated in a vacuum. The residue was reconstituted with 1 ml of methanol and analyzed using gas chromatography-mass spectrometry (GC-MS 7890A; Agilent Technologies, USA) equipped with a 5975 mass-selective detector and a 7693 automated liquid sampler, fitted with a DB-5MS GC column (30 m length, 0.25 mm inner diameter, and 0.25 μm film thickness).

A GC-MS 7890A equipped with an Agilent 5975C quadrupole mass spectrometer controlled by Enhanced ChemStation MSD ChemStation E.01.00.237 (Agilent, Santa Clara, CA) was used to analyze compounds in the extracted volatile oil. Gas chromatography conditions: column was a HP INNOWax (30 m×0.25 mm×0.25 µm), inlet temperature 200°C, column flow 1.0 mL/min, ion source temperature 200°C, injection volume 1 µL and split ratio 10:1. Temperature-programmed conditions: initial temperature 80°C, with 10°C/min rise to 150°C, maintained 1 min, then with 5°C/min rise to 200°C, maintained 3 min, then with 5°C/min rise to 250°C and the carrier gas was He [42] (link)–[44] (link). The content was calculated by peak area normalization method.

Volatile compound analysis was performed as described previously [23 (link)]. Volatile compounds were analyzed using gas chromatography–mass spectrometer (GC-MS 7890A; Agilent Technologies) equipped with a DB-WAX column (60 m × 0.25 mm × 0.25 µM) and an autosampler (Multi-Purpose Sample with DHS option, MPS, Gerstel, Germany); the samples were initially extracted using solid-phase microextraction (SPME) fibers (DVB/CAR/PDMS, 50/30 µM, Supelco-57329-U), and absorbed onto polydimethylsiloxane (PDMS) fibers at 100 rpm for 30 min at 50 °C. The SPME fibers (DVB/CAR/PDMS, 50/30 µM, Supelco-57329-U), which extracted the volatile compounds, were automatically injected into a GC-MS injection port, and the volatile compounds were thermally desorbed at 250 °C for 3 min and analyzed using GC-MS with a constant helium flow rate of 1 mL/min. The temperature programs were as follows: 40 °C for 3 min, 2 °C/min up to 150 °C, 150 °C for 10 min, 4 °C/min up to 200 °C, and a final hold at 200 °C for 10 min. Electron impact ionization (70 eV) was performed at a full scan range of 50–550 m/z. Each volatile compound was identified based on a mass spectral library (WILEY 10N). The amounts of the identified volatile compounds were measured from the peak areas of the GC/MS chromatograms for each sample, using the internal standard method and presented as μg/g.