Phytochemical Composition of Clonally Propagated Artemisia annua L. in Different Geographical Locations and Its Commercial Supplement Quality

Global cultivation of Artemisia annua L. for the isolation of artemisinin as the current best antimalarial therapeutic mainly takes place on large plantations, but there is an increasing cultivation of the plant for more local use and the supplement market. Phytochemical consistency is a major concern among growers and also regulatory bodies. Long-term cultivation and harvest of field-grown clonal A. annua have not been measured for consistency and between different geographical regions. Here, artemisinin and other phytochemicals were measured in clonal A. annua grown in two different US geographical locations. Five Florida (FL) and nine Massachusetts (MA) crops were analyzed for artemisinin and flavonoids. TLC (thin layer chromatography) profiles and mass spectrometry analysis were also compared. Artemisinin content dropped by about 10% after transfer from MA to FL, but the flavonoid content increased 2.6-fold. Artemisinin and flavonoid profiles were relatively consistent within each location, but flavonoids differed significantly between the two locations. We also analyzed the artemisinin content of several US commercial A. annua and artemisinin supplements. Despite manufacturer claims, about half the samples contained no detectable artemisinin. Together, this study enhances the knowledge about A. annua field crops and Artemisia/artemisinin supplements being used globally and in the US for therapeutic purposes.