Artemisia annua

Artemisia annua (Quing-hao), a fern-like weed, has been used in Chinese medicine for more than 2000 years in the treatment of fever. The active principle, artemisinin (quinghaosu, QHS, artenuin), a sesquiterpene lactone with a characteristic peroxide bridge, was isolated by Chinese scientists in 1972 from the leafy portion of the plants (). Assays carried out on other species of Artemisia failed to show any appreciable amount of artemisinin (TDR 1981). However, other species of the genus are considered important as a source of medicines and flavors. From Artemisia douglasiana, for example was isolated dehydroleucodin (DHL), a sesquiterpene lactone with antiulcerous properties (). Artemisia dracunculus, also known as tarragon, is used as a spice in cooking and to flavor vinegar, and Artemisia absintium used in the production of volatile oils ().

Botanical Description

Artemisia annua (), popularly known as sweet Annie, annual wormwood, or sweet wormwood is a member of the Compositae family (Asteraceae). It is an annual herbaceous plant that grows in wild forms in different parts of the world, exhibiting great variety in both shape and size. It ranges from small, almost prostrate plants to tall, erect specimens which grow in Europe and America. It may have strong woody stems and reaches a height of 2 m. It presents two to three leaves of pinatisected structure, with linear segments. The inflorescences (capitula) are yellow, small with laxe panicles, and muitifloral (). The plant blooms during the months of February and March, and its reproduction is by seed that can germinate in September. Agronomical cultures have been carried out ().

Artemisinin is the antimalarial principle isolated from Artemisia annua. In view of the worldwide resurgence of malaria, and parasite resistance to many drugs now in common use, it is recognized that new drugs are urgently needed. The bio-technological approach is an interesting alternative for artemisinin production. Dedifferentiated cultures such as calli and suspension have been obtained, but accumulation of artemisinin is very poor. For this reason differentiated organ cultures are an interesting approach. In this respect, transformed and non-transformed cultures have been obtained, and are being investigated.

 

Selections from the book: “Medicinal and Aromatic Plants V”, 1993.