Abstract:

The volatile oil of garlic was extracted by hydrodistillation method and gas chromatography-mass spectrometry was applied to analyse the compounds in the oil. The best extraction conditions for high-content, effective components were obtained through optimization. The capillary column was an HP-5MS column (25 mm×0.25 mm i.d.×0.25 μm); oven temperature increased with a rate of 5 ℃/min from 80 to 300 ℃, and then maintained for 20 min; sample size of 1 μL; split ratio of 100∶1; carrier gas of helium (1 mL/min). Mass spectra were obtained at 70 eV. The temperatures of injector base, ionization source were maintained at 270 ℃, 230 ℃ respectively. Under these conditions, twenty compounds in the volatile oil of garlic were isolated and identified, and the content of each was determined. Sulfur-containing compounds were found to be the principal components, of which the major compound was diallyl trisulfide with the content of more than 30%, which is higher than the others in the literature. The experimental results also indicated that hydrodistillation method is an effective method for officinal component extraction. In addition, it was also demonstrated that the garlic volatile oil was stable when stored at 0 ℃ for 6 months.

Key words: diallyl trisulfide , garlic volatile oil, hydrodistillation, gas chromatography-mass spectrometry