A Design of Experiment Approach for Ionic Liquid-Based Extraction of Toxic Components-Minimized Essential Oil from Myristica fragrans Houtt. Fruits †

The effect of the addition of ionic liquids (ILs) during the hydrodistillation of Myristica fragrans Houtt. (nutmeg) essential oil was studied. The essential oil of M. fragrans is characterized by the presence of terpenes, terpenoids, and of phenylpropanoids, such as methyl eugenol and safrole, that are regarded as genotoxic and carcinogenic. The aim of the work was to determine the best ionic liquid to improve the yield of the extraction of M. fragrans essential oil and decrease the extraction of toxic phenylpropanoids. Six ILs, namely 1,3-dimethylimidazolium chloride (1), 1,3-dimethylimidazolium dimethylphosphate (2), 1-(2-hydroxyethyl)-3-methylimidazolium chloride (3), 1-(2-hydroxyethyl)-3-methylimidazolium dimethylphosphate (4), 1-butyl-3-methylimidazolium chloride (5), and 1-butyl-3-methylimidazolium dimethylphosphate (6), were prepared by previously reported, innovative methods and then tested. An experimental design was used to optimize the extraction yield and to decrease the phenylpropanoids percentage using the synthesized ILs. The influence of the molarity of ILs was also studied. MODDE 12 software established 0.5 M 1-butyl-3-methylimidazolium chloride as the best co-solvent for the hydrodistillation of M. fragrans essential oil.