Response Surface Modeling of Essential Oil Components from Mentha piperita by Supercritical Fluid Extraction: Box-Behnken Experimental Design

Abstract

The oil and extracts of Mentha piperita cultivated in Iran were obtained using supercritical carbon dioxide method. The oil and extracts were then analyzed by GC-FID and GC-MS. A fractional factorial design (24 − 1) was applied to investigate the effects variables and their interactions on the supercritical fluid extraction (SFE) of oils from Mentha piperita. The variables were pressure, temperature, and percent of modifier and extraction time. The results showed that the pressure, temperature and percent of modifier are significant (p < 0.05), while the extraction time was found to be insignificant. The response surface methodology (RSM), based on Box-Behnken design was used to obtain the optimum conditions of the significant parameters (pressure, temperature and percent of modifier). The optimal conditions could be obtained at a pressure of 34.8 MPa, temperature of 67.0°C, and 10.0 % (v/v) for modifier (ethanol). The main extracted components using SFE were α-terpinene (26.6 %), isomenthone (17.6 %) and trans-carveol (20.2 %).