Isolation, characterization and quantification of artemisinin by NMR from Argentinean Artemisia annua L.

Artemisinin is a polycyclic sesquiterpene lactone present in leaves and inflorescences of wild Artemisia annua L. That substance is highly effective against multidrug-resistant strains of Plasmodium falciparum, which is the etiological agent of the most severe form of malaria. The known procedures for the extraction and isolation of artemisinin were performed and optimized. The extractions were carried out with different solvents and/or their mixtures. Chromatographic methods (TLC, HPLC and GC) were employed for the characterization and quality control of artemisinin and other metabolites presents in the solvents extracts. qNMR method was also employed for determination the artemisinin content in the solvents extracts. The convenience of the above procedures was critically evaluated by comparison of the analytical results with those derived by applying the classic isolation methods by Soxhlet extraction. The values of artemisinin content in Argentinean plants extracts were in the 0.2-0.3%. (p/p) range.