Optimization of artemisinin extraction from Artemisia annua L. with supercritical carbon dioxide + ethanol using response surface methodology

Malaria is a high priority life‐threatening public health concern in developing countries, and therefore there is a growing interest to obtain artemisinin for the production of artemisinin‐based combination therapy products. In this study, artemisinin was extracted from the Artemisia annua L. plant using supercritical carbon dioxide (SC‐CO₂) modified with ethanol. Response surface methodology based on central composite rotatable design was employed to investigate and optimize the extraction conditions of pressure (9.9–30 MPa), temperature (33–67°C), and co‐solvent (ethanol, 0–12.6 wt.%). Optimum SC‐CO₂ extraction conditions were found to be 30 MPa and 33°C without ethanol. Under optimized conditions, the predicted artemisinin yield was 1.09% whereas the experimental value was 0.71 ± 0.07%. Soxhlet extraction with hexane resulted in higher artemisinin yields and there was no significant difference in the purity of the extracts obtained with SC‐CO₂ and Soxhlet extractions. Results indicated that SC‐CO₂ and SC‐CO₂+ethanol extraction is a promising alternative for the extraction of artemisinin to eliminate the use of organic solvents, such as hexane, and produce extracts that can be used for the production of antimalarial products.