Chromback

The GC–MS investigation was performed utilizing a gas chromatograph connected with a VG Analytical 70-250S mass spectrometer (VG Analytical Ltd., Manchester, UK). A fused silica capillary column (CP-Sil 5 CB, 25 m × 0.25 mm i.d., film thickness 0.4 μm, from Chromback, Varian) was the used stationary phase. As a carrier gas, helium was utilized at a flow rate of 1 mL/min. The temperature of the injector was 200 °C. The oven temperature was raised from 80 °C to 270 °C at 10 °C/min, and finally held isothermally for 20 min. An electron impact mode of 70 eV was utilized for the detection with a mass scan range from 35 to 600 amu.

The GC–MS analysis of lemon essential oil was separated and identified using a Hewlett-Packard 5890 gas chromatograph, coupled to VG Analytical 70-250S mass spectrometer. The GC was equipped with a fused silica capillary CP-Sil 5 CB column (25 m × 0.25 mm i.d., film thickness 0.40 μm, from Chromback, Varian). Helium was used as carrier gas at a flow rate of 1 mL/min. The oven program started with an initial temperature of 80 °C held for 2 min and then the oven temperature was heated at 10 °C/min to 270 °C and finally held isothermally for 20 min. For GC–MS detection, an election ionization system, with ionization energy of 70 eV was used. A scan rate of 0.6 s (cycle time: 0.2 s) was applied, covering a mass range from 35 to 600 amu.