Comparison of two methods for extraction of dill essential oil by gas chromatography-mass spectrometry coupled with chemometric resolution techniques

Abstract

The essential oil components of Iranian Anethumgraveolens L.(dill) were extracted using a Clevenger-type apparatus and microwave-assisted hydro distillation and analysed by gas chromatography-mass spectrometry. A multivariate curve resolution approach was used to overcome the problem of background, baseline offset, and overlapping/embedded peaks. Based on the results related to the GC-MS, 33 and 18 components for dill oil were extracted by hydro distillation and microwave-assisted hydro distillation, respectively. The numbers were extended to 64 and 55 components with concentrations higher than 0.01 g/100 g dry-solids using chemometric techniques. The results of this study showed that hydro distillation was suitable for extraction of β-phellandrene, O-cymen, 3, 6-Dimethyl-2, 3, 3a, 4, 5, 7a-hexahydrobenzofuran, Thymol, Germacrene D, Dill Apiole, 3-Octadecyne, and Phytol; and microwave distillation was suitable for the extraction of α-pinene and α-Phellandrene.