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Artemisia annua L., Asteraceae, known as sweet
Annie or annual wormwood, is an annual herb native to Asia,
most probably China. The plant has become naturalized in many
countries including Argentina, Bulgaria, France, Hungary,
Romania, Italy, Spain, the United States, and Yugoslavia. In
1971, extraction of aerial parts of A. annua with
low-boiling solvents, such as diethylether, produced a
compound mixture with antimalarial properties on infected mice
and monkeys. The main active principle, artemisinin was
isolated as a sesquiterpene lactone with an endoperoxide
bridge. Artemisinin is now available commercially in China and
Vietnam as an antimalarial drug efficacious against
drug-resistant strains of Plasmodium, the malarial
parasite. A semisynthetic drug based on artemisinin
(artemether) has been recently registered in Africa as
Paluther. Artemisinin also has phytotoxic activity, even on
A. annua, and is a candidate as a natural herbicide.
Artemisia annua is a vigorous annual weedy short
day plant with a critical photoperiod of 13.5 hr. The plant is
usually single-stemmed reaching about 2m in height with
alternate branches and alternate, deeply dissected, aromatic
leaves ranging from 2.5 to 5.0 cm in length as well as tiny
yellow nodding flowers (capitula) only 2 or 3 mm across
displayed in lose panicles.
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