Multiple liquid-liquid extraction of dissolved compounds in immortelle hydrosol with four different solvents

Immortelle, a revered Mediterranean medicinal plant, is celebrated for its potent essential oil renowned in the cosmetic industry for its skin-enhancing properties. Yet, immortelle hydrosol, an often-overlooked byproduct, holds promise in cosmetics due to its compatibility with polar active ingredients. This study investigates the chemical composition of immortelle hydrosol by employing liquid-liquid extraction (LLE) to transfer volatile organic components into nonpolar solvents. Four solvents - chloroform, dichloromethane, hexane, and benzene - were assessed through ten consecutive extractions from industrially produced immortelle hydrosol. Quantification was achieved using GC analysis with tetradecane as an internal standard. Chloroform emerged as the most efficient solvent, yielding 2447.0 mg/L of volatile compounds, surpassing dichloromethane, hexane, and benzene. Key compounds in immortelle hydrosol included 3-pentanone, 2-methyl-1-butanol, and γ-terpineol. Importantly, the study revealed that a portion of essential oil compounds persists in the hydrosol even after ten LLE cycles, with optimal results achievable in five extractions (~92 % in most cases).