Varian 3400

Separation and identification of the flower and butterfly volatiles were made by GC-MS using a Varian 3400 gas chromatograph (GC) (Varian, Palo Alto, CA, USA) coupled with a Finnigan SSQ 7000 mass spectrometer (MS) (Thermo-Finnigan, San Jose, CA, USA). A DB-WAX column (length 30 m, inner diameter 0.25 mm, and film thickness 0.25 μm; J & W Scientific, Folsom, CA, USA). The temperature programme started isothermal at 40 °C for 1 min, then was increased 5 °C/min to 220 °C and afterwards was held isothermal for 10 min. The injector temperature was kept isothermal at 225 °C and helium was used as the carrier gas at 69 kPa. The mass spectrometer was operated with full scan mode (mass range m/z 30–400 m/z) and mass spectra were obtained at 70 eV with the ion source at 150 °C. Identification of the compounds was made by comparison of their retention times and mass spectra with those of authentic reference standards as well as by comparing mass spectral data of natural products with those available from NIST mass spectral data base, version 2.0 (National Institute of Standards and Technology, USA).

GC 5890 II (Hewlett-Packard GmbH, Homburg, Germany) coupled with quadrupole mass spectrometer (SSQ 7000, Thermo-Finnigan, Bremen, Germany) was used for the identification of the essential oil compounds. Instrumental settings were Gas: ⁴He (2 mL/min); Temp: T₀/45 °C, T₂/isothermal, T₁/300 °C, T₂/isothermal, detector/300 °C, and injector/250 °C, Split ratio: 1:20. Varian 3400 (Varian GmbH, Darmstadt, Germany) was used for GC analyses with OV-5 fused bonded column (Ohio Valley, OH, USA) and a Flame Ionization Detector (FID) for quantitative determination of the components. Mean of 3 independent runs was used to calculate areas under the peaks (AUP) using an SRI Instrument (Torrance, CA, USA) and the total area was considered as 100%. Wiley Registry of Mass Spectral Data 8th edition, National Institute of Standards and Technology (NIST) Mass Spectral Library (December 2005), and the literature were used to compare and identify the active constituent of spectral data [29 (link),30 (link)].