title: Artemisinin, Related Sesquiterpenes, and Essential Oil in Artemisia annua During a Vegetation Period in Vietnam.
abstract: The active principle of ARTEMISIA ANNUA L., artemisinin, is currently being developed to a registered antimalarial drug. For production purposes, plants with a high artemisinin content are required. We followed the development of the artemisinin content and of the biosynthetically related sesquiterpenes artemisinic acid, arteannuin B, and artemisitene in A. ANNUA plants, during a vegetation period in Vietnam, where this species is indigenous. In addition, the essential oil content and composition were studied. Samples of leaves, buds, flowers, or post-bloom flowers and fruits were taken at different stages: vegetative (5, 6, and 8 months old), at mass formation of buds (9 months), at full bloom (10 months), and post-bloom (10S months). The highest artemisinin content (0.86% dry wt) was present in the leaves of 5 months-old plants. At this stage also the highest leaf yield was found. Subsequently, the artemisinin content gradually dropped. At the age of 5 months the highest artemisinic acid and arteannuin B contents, 0.16 and 0.08% dry wt, respectively, were found as well. Artemisitene was present at all stages of development, ranging from 0.002 to 0.09% dry wt. With 1.9% v/w, the essential oil content was maximal just before flowering and was composed of 55% monoterpenes and 45% sesquiterpenes. At all other stages (0.4 - 1.0% v/w oil) this ratio was ca. 30%/70%. The main components of the oil were camphor and germacrene-D.
authors.affiliation: Department of Pharmacential Biology, University Centre for Pharmacy, University of Groningen, A. Deusinglaan 2, NL-9713 AW Groningen, The Netherlands.
authors.forename: H J
authors.initials: HJ
authors.lastname: Woerdenbag
authors.forename: N
authors.initials: N
authors.lastname: Pras
authors.forename: N G
authors.initials: NG
authors.lastname: Chan
authors.forename: B T
authors.initials: BT
authors.lastname: Bang
authors.forename: R
authors.initials: R
authors.lastname: Bos
authors.forename: W
authors.initials: W
authors.lastname: van Uden
authors.forename: P
authors.initials: P
authors.lastname: Van Y
authors.forename: N
authors.initials: N
authors.lastname: Van Boi
authors.forename: S
authors.initials: S
authors.lastname: Batterman
authors.forename: C B
authors.initials: CB
authors.lastname: Lugt