Co-detection of eugenol and butylated hydroxyltoluene by green and selective hydrodistillation of Heliotropium europaeum L. using ionic liquids as additives

This study is the first work that focuses on unconventional ionic liquids hydrodistillation (IL-HD) extraction of the essential oil of Heliotropium europaeum L. using ionic liquids (ILs) as additives. Two ILs based on 1-butyl- 3-methylimidazolium were used by switching the anions (Cl- and PF6-). The effect of mass percent adding ILs on its yield and composition was evaluated. Compared to conventional hydrodistillation (HD), ILs-HD gives a higher yield of essential oils (0.10-0.36%). Particularly, with [C4mim] [PF6], observation of morphological changes using scanning electron microscopy (SEM) confirmed the effectiveness of the ionic liquid in this distillation process. The GC-MS analysis of essential oils (EOs) revealed the presence of sixty-six compounds in HD, ILs-HD methods. GC-MS analyze of the EOs revealed predominance of Eugenol (1.70-72.35%), Butylated hydroxytoluene (8.95-65.39%) and Phytol (18.20%). The new distillation methods of H. europaeum with ILs identifies more compounds (50 compounds in ILs-HD [C4mim] [PF6]; 22 compounds in ILs-HD [C4mim] [Cl]) than conventional hydrodistillation (25 compounds in HD). Therefore, the ILs-based hydrodistillation approach is superior in improving the production of EOs. It is important to emphasize that the data presented in this study are not yet available for any of this Algerian Heliotropium species of genus and reveal in literature the great potential of this medicinal plant as a source of novel bioactive extracts with potential therapeutic uses.