Chiral terpene analysis

A subsample of 45 of the original 150 samples was used for the analysis of chirality for five of the analyzed terpenes: β-pinene, α-pinene, camphene, limonene, and sabinene. The subsample was selected so that there were 15 samples of each cone type. Within each cone type, the samples selected were chosen randomly.

Samples were again analyzed by the British Columbia Ministry of Environment, Knowledge Management Branch, North Road Laboratory, using the previously obtained methanol extracts which, as already noted, showed a higher extraction efficiency when compared to the hexane extracts. Gas chromatographic-mass spectrometer detection analyses were used to process samples, and standards were matched to the retention time and mass spectrum of each compound. To carry out the procedure, approximately 0.5 ml of extract was placed in a 2 ml autosampler vial, and then analyzed using a Clarus 500 GC with a Claus 560 S mass spectrometer, with built in autosampler, which was fitted with a Cylcodex-B (Agilent, 30M, 0.25 mm id, 0.25 μm film) column. The injection was split (rate of 20 mL/min, approximately 10.3:1; injector temperature of 250°C), and the carrier gas utilized was helium (pressure 17 psi). For the temperature program, the oven temperature was initially held at 75°C for 15 min, then increased by 20.0°C/min to 230°C, where it was held for 15 min.