Optimization of Supercritical CO2 Extraction of Essential Oil from Artemisia annua L. by Means of Response Surface Methodology

Abstract

In this paper, the extraction of essential oils from Artemisia annua L. with supercritical carbon dioxide method has been studied by means of the parameter optimization using response surface methodology. The extracted oil was then purified with molecular distillation. The results showed that the response surface methodology was an effective tool to predict optimal values of extraction parameters, with which the crude oil yield of 11.17% could be achieved at 25 MPa pressure, 50°C, 25 g/minute carbon dioxide flow rate and 2 hours extraction time. The purification below 120°C could produce high-quality essential oil with the yield of 56.1%. The essential oil was mainly composed of six bioactive terpenes, namely limonene, (1s)-α-pinene, β-pinene, β-farnesene, α-caryophyllene, γ-elemene. It was suggested that A. annua L. was a potential source of antimicrobial/ antioxidant compounds and the combination of supercritical carbon dioxide and molecular distillation was a good process for the isolation of essential oil.