Removal of Toxic Aqueous Essential Oils from Chamaecyparis obtusa by Liquid-Liquid Extraction and Solid-phase Extraction

Abstract

A method was developed to remove five toxic aqueous essential oils (a-terpinene, g-terpinene, linalool, a-terpineol and a-terpinyl acetate) from Chamaecyparis obtusa by liquid-liquid extraction and solid-phase extraction with gas chromatography analysis. The best liquid-liquid extraction conditions were as follows: extraction solvent, 1-octanol and an essential oil:1-octanol ratio of 7:3. The best solid-phase extraction conditions were as follows: sorbent, C₁₈; and washing and elution step solvents of 2 mL 1-octanol and 1 mL water, respectively. GC-FID was used to detect the five toxic aqueous essential oils. This method was simple and could remove the toxic aqueous compounds from natural product oils.