Extraction of Cuminum cyminum essential oil by combination technology of organic solvent with low boiling point and steam distillation

Extraction of essential oil from Cuminum cyminum seeds using a combination of organic solvent with low boiling point and steam distillation was explored. The effect of different parameters, such as particle size (40, 60, 80 mesh), temperature (°C) 10, 15, 20 and extraction time (3, 5, 8 h), on the extraction yield was investigated using three-level orthogonal array design. The experimental results showed that the temperature had the largest effect on the yield of the extract (oleoresin), followed by extraction time and particle size. The optimum parameters, such as temperature, particle size, and extraction time were in turn 20 °C, 80 mesh, and 8 h. Essential oil of C. cyminum seeds obtained by supercritical fluid extraction (SFE), hydrodistillation (HD), combination technology of organic solvent with low boiling point and steam distillation (OS-SD) were further analysed by gas chromatographic/mass spectrometric detection to compare the extraction methods. Forty-five compounds in the C. cyminum essential oil were identified, showing that the composition of the extraction by different methods was mostly similar, whereas relative concentration of the identified compounds was apparently different. General characteristics of the C. cyminum essential oil obtained by different methods were further compared, and OS-SD was considered as the optimum process among the three processes to obtain C. cyminum essential oil for high quality, simple technology and low cost.