Sweet Wormwood Artemisia annua

190 Sweet wormwood (Artemisia annua) was first described in 1753 by the Swedish botanist and physician Carl von Linni (1707-1778) in Species Plantarum. [460] 

ADHl-catalysis. [463] The double bond at C-11/13 is reduced by DBR2, a member of the enoate reductase family, and the aldehyde dehydrogenase ALDHl leads to the oxidation product dihydroartemisinic acid. [464] The further oxidation cascade is non-enzymatic, however stereoselective, and yields (+)-artemis-inin via relatively unstable intermediates. Geoffrey D. Brown at the University of Reading was able to demonstrate, that the Hock rearrangement of a hydroperoxide, followed by oxidation of the resulting enol with triplet oxygen, are the key steps of this sequence. [465] 

ADS Amorpha-4,11-diene synthase CYP71AV1 Amorphadtene-12-hydroxylase 

Cytochrome P450 reductase Cvfochrome B5 reductase Alcohol dehydrogenase Artemisihic aidehyde-Al 1 (i 3)-reductase 

Experiments with and -labelled precursors provided unambiguous evidence, that there are several branch points in the biosynthesis of artemisinin. The most prominent sesquiterpene metabolites in sweet wormwood are, aside from artemisinin, artemisinic acid and arteannuin B, which branch off at the artemisinic aldehyde stage. [465] 

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How do traditional remedies fare in such trials Some perform quite well and prove to be highly effective, but others are no better than placebos. One striking success is an extract of sweet wormwood (Artemisia annua), which Chinese physicians have prescribed for the chills and fevers of malaria for more than two thousand years. About twenty-five years ago, Chinese chemists obtained from sweet wormwood its principal active component, a compound now called artemisinin. Clinical trials on malaria patients in Southeast Asia agreed with Chinese tradition on the value of artemisinin and also identified a few even more useful drugs prepared from it in the laboratory. These compounds are effective against the deadliest form of malaria and are now frequently the therapies of choice for treating it. 

Artemisinin is used here as an example of a plant sesquiterpenoid with both traditional value as well as with medicinal and social value in the twenty-first century. Research on artemisinin has also established new benchmarks for biochemical engineering and functional genomics of plant terpenoids. Artemisinin is a functionalized sesquiterpene with a unique peroxide linkage from the sweet wormwood Artemisia annua). Chinese herbalists have used it since ancient times, and it is now used for its unique efficacy to treat multidrug-resistant strains of the malaria parasite Plasmodium falciparum. Its medicinal importance has prompted studies into its biosynthesis and its biochemical engineering so that cost-effective methods for producing it in large scale and in consistent quality may be realized. 

Two major breakthroughs of the past few decades have renewed the assault of scientists to this infective disease. The first is the complete sequencing of the genome of Plasmodium falciparum [4] that is expected to provide useful information for the identification of new drug targets. The second is the discovery by Chinese researchers of artemisinin (qinghaosu), an endoperoxide sesquiterpene lactone, as the active principle of the sweet wormwood, Artemisia annua, an herbal remedy used in folk Chinese medicine for 2000 years [5]. This molecule and its... 

However, the most modern drugs in our armoury to fight malaria infections are derivatives of artemisinin. This natural product originates from the sweet wormwood, Artemisia annua), a traditional Chinese herbal medicine, which had already been in use for malaria treatment some 1,300 years prior to quinine, albeit its active principle was only discovered in the 1970s. 

While the mode of action of artemisinin is not yet completely understood, the drug was isolated in the 1970s from sweet wormwood Artemisia annua). The plant known in Traditional Chinese Medicine to treat malaria for at least 1,600 years. 

Artemisin Antimalarial Sweet wormwood (Artemisia annua L)... 

In 1972, Chinese researchers isolated, by extraction at low temperature from a plant, a crystalline compound that they named qinghaosu [the name artemisinin (la) is preferred by Chemical Abstracts, RN 63968-64-9]. The plant source of artemisinin is a herb, Artemisia annua (Sweet wormwood), and the fact that artemisinin is a stable, easily crystallizable compound renders the extraction and purification processes reasonably straightforward. The key pharmacophore of this natural product is the 1,2,4-trioxane unit (2) and, in particular, the endoperoxide bridge. Reduction of the peroxide bridge to an ether provides an analogue, deoxyartemisinin 3, that is devoid of antimalarial activity. ... 

Qinghao (Sweet Wormwood) is the dried aerial parts of the herb Artemisia annua L. (Asteraceae family), which has been used in China for centuries to treat fever and malaria. Artemisinin (Nl) (Qing Hao Su) (128), the active principle, directly kills Plasmodium falciparum (malaria parasites) with little toxicity to animals and humans. Thus, it is a clinically effective, safe, and rapid antimalarial agent (129, 130). The novel endo-peroxide link is essential for the antimalarial activity. 

Artemisia annua (sweet wormwood, qing hao) has been used in Chinese medicine for well over 1000 years. The earliest recommendation is for the treatment of hemorrhoids, but there is a written record of use in fevers dated 340 A.D. Modem development dates from the isolation of a highly active antimalarial, artemisinin (qing-haosu), in 1972, and has been carried out almost entirely in China. Much of the original 1 iterature is therefore in Chinese, but there is an excellent review on qinghaosu by Trigg (196) and an account of the uses of A annua (197). This section is largely a summary of these two articles. 

Figure 6.13 Principle of an evaporative light-scattering detector and its application for plant constituents. (Chromatograms after J. L Veuthey, Analytical Pharmaceutical Chemistry, University of Geneva.) Conditions sample, extract of Artemisia annua (sweet wormwood) column, 12.5cm x 4mm i.d. stationary phase, Nucleosil 100 Cqg/ 5pm mobile phase, 1 ml min water with trifluoroacetic acid (pH 3)/acetonitrile (39 61). Peaks 1 = artemisinin 2 = artemisinic acid.

History. For thousands of years Chinese herbalists treated fever with a decoction of the plant called "qinghao", Artemisia annua, "sweet wormwood" or "annual wormwood" belonging to the family of Asteraccae. In the 1960s a program of the People Republic of China re-examined traditional herbal remedies on a rational scientific basis including the qinghao plant. Early efforts to isolate the active principle... 

Plant natural products have traditionally been harvested through extractiOTi methods, as evidenced by the preparation of traditional medicines and the steeping of tea leaves and coffee beans for millenia. Since plant natural products are generally found at low levels in plant biomass, extraction is usually not a sustainable mass production avenue. Although extraction is still utilized to harvest APIs like the antimalarial drug artemisinin (from Artemisia annua, known as Sweet Wormwood) and the chemotherapeutic pacUtaxel (from Taxus brevifolia, the Pacific yew tree) when chemical synthesis is difficult or expensive, there is a trend and growing necessity to shift toward alternative production platforms to lower cost and increase avaUabiUty [27, 28],... 

Artemisinin, a sesquiterpene lactone endoperoxide and isolated from aerial parts of Artemisia annua L. plants (family Asteraceae commonly known as sweet wormwood), is popular as a potent, promising, highly effective, safe, and best therapeutic agent against drug-resistant strains of Plasmodium sp. The low yield of artemisinin content, is a serious limitation to its ability and affordablity to the most malaria sufferers. The chemically synthesized artemisinin is also costly due to low yield of the process. The World Health Organization (WHO) recommends the use of artemisinin-based combination therapies (ACTs), for the first-line treatment of malaria. To date, A. annua L. 

Artemisinin, another sesquiterpene lactone, contains a rare endoper-oxide bridge that is necessary for its antimalarial activity. Artemisinin is derived fi om an antique Chinese herbal remedy and has been isolated fi om Artemisia annua, also known as qing hao or sweet wormwood, a species of the Asteraceae family. This plant has been used in Chinese herbal medicine for over 200 years. Artemisinin and its de-... 

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