Supercritical fluid extraction of volatile components from Bunium persicum Boiss. (black cumin) and Mespilus germanica L. (medlar) seeds

Volatile constituents of black cumin and medlar seeds were obtained by supercritical carbon dioxide extraction and analysed by gas chromatography-mass spectrometry (GC-MS). A total of 16 compounds accounting for 99.36% of the black cumin supercritical fluid extraction (SFE) extracts were identified. γ-terpinene (37.98%), cuminaldehyde (11.48%) and α-methyl-benzenemethanol (25.55%) were the major compounds identified in black cumin. The SFE method has been compared with hydrodistillation. SFE products were found to be markedly different from the corresponding hydrodistilled oil. A remarkable amount of ρ-cymene was present in the hydrodistilled essential oil, also the ratio of γ-terpinene and cuminaldehyde in distilled oil was high in comparison with the supercritical carbon dioxide extract. Also, supercritical fluid extraction of α-methyl-benzenemethanol was more selective. However, cuminyl alcohol was not found in the SFE products. The results showed that by using supercritical carbon dioxide only 3 components represented more than 99.99% of the medlar oil, and benzaldehyde (98.49%) was the major component.