Artemisia annua L. (Asteraceae) is an annual herb native of Asia. This plant has been used for many centuries in traditional Chinese medicine for the treatment of fever and malaria. Conventional methods for the extraction of artemisinin from A. annua including solvent extraction, Soxhlet extraction, and heat reflux extraction are characterized by long extraction times and the consumption of large volume of solvents. A simple, rapid, and precise microwave-assisted extraction process was optimized for fast sample preparation for the faster quantitative determination of artemisinin, potential new generation antimalarial drug, from dried leaves of Artemisia annua L. A simple experiment was designed for the optimization of the appropriate solvent under same extraction conditions. The selected appropriate solvent was then standardized for various different extraction variables. The major parameters studied showed effects on extraction efficiency including processing time, strength of microwave, moisture content, volume and nature of the solvent. The most favorable conditions were obtained by using plant material of 25 mesh (particle size) extracted with acetone for 120 seconds at 160？W (i.e., 20% of total power). Quantitative analysis was performed using thin-layer chromatography coupled with a densitometer (TLC densitometry). The results showed that MAE can be used as an efficient and rapid method for the extraction of the active components from plants. 1. Introduction Artemisia annua L. (Asteraceae, formerly Compositae), also known as qinghao, annual or sweet wormwood, is an annual herb native of Asia. This plant has been used for many centuries in traditional Chinese medicine for the treatment of fever and malaria. 300 million illnesses and at least one million deaths are caused by malaria in a year. Malaria is often referred to as disease of the poor. Therefore, it is the need of the hour to develop an effective and low-cost drug to cure malaria. Artemisinin (Figure 1), a sesquiterpene lactone with an endoperoxide bridge, which is rare in secondary metabolites, is isolated from Artemisia annua L. Artemisinin is responsible for the therapeutic effects of the plant. It acts as a bullet to kill the Plasmodium, causative agent of malaria by oxidative damage. Newer research shows serious anticancer [1] benefits too, as a bonus of the plant. Figure 1: Artemisinin. Synthetic routes [2–4] of artemisinin are very tedious and expensive compared to its natural isolation, and thus, synthetic artemisinin is not a commercially viable option. Low and variable
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