Keywords

These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

2.1 Introduction

Artemisia annua L is well-known medicinal plant (Bhakuni et al. 2001; Emadi 2013; Tayebe et al. 2012). A. annua is the only planta medica that has been recognized to research and developed as the standards of western medicine research by the WHO in China. It is a famous herb, known for its highest efficiency and lowest toxicity in treating ague (Wang et al. 2011). It is an aromatic annual herbaceous plant (Ellman 2010; Huang et al. 2010; Zanjani et al. 2012; Liu et al. 2013; Misra et al. 2013) belongs to genus Artemisia (Liu et al. 2013), family Asteraceae (Compositae) (Geldre et al. 2000; Mannan et al. 2010; Tayebe et al. 2012; Zanjani et al. 2012) and commonly known as sweet wormwood or Qinghao (Huang et al. 2010; Emadi 2013). It is the only member of genus Artemisia with an annual growth cycle (Willcox et al. 2004). Qing Hao is an ancient Chinese name for A. annua, which means “green herb.” There are two different theories exist regarding the origin of name. According to first theory word, Artemisia is named after the name of Greek Goddess “Artemis” which literally mean “she who heals sickness.” It was belief of local people that she heals the diseases and eliminates the evil. Second theory report that it is named after the Queen’s name “Artemisia of Caria”. She was the queen of Turkey (Ferreira 2004; Willcox et al. 2004). A. annua has remained the part of Chinese traditional medicine more than 2,000 years, and currently, it is endemic to China (Olliaro and Trigg 1995; Ferreira 2004; WHO Monographs 2006; Ellman 2010; Mannan et al. 2010). However, A. annua has been recognized all over the world since 1970s after the discovery of only natural phytomedicinal source for production (Huang et al. 2010) of the antimalarial lactone artemisinin. Presently, this important phytoconstituent and its derivatives have been widely explored for cure of drug-resistant malaria (Laughlin 2002; Liu et al. 2013; Emadi 2013; Misra et al. 2013). A. annua has been established as crop in agriculture after the statement of World Health Organization, as a valuable component of combinatorial therapy for malaria since 2001 (Ferreira 2007).

2.1.1 Origin

This plant is native of Asia and most appropriately originates in China particularly in Suiyuan and Chahar provinces. China has long history of cultivation of A. annua and skillful for its unique method of extraction of artemisinin, hence, it has become first country for isolation of artemisinin from plant extracts. In addition, China has also become the largest country on the global market as a supplier of raw material of A. annua (WHO Monographs 2006; Ferreira and Janick 2009; Huang et al. 2010; Sharma et al. 2011; Das 2012). There are very few studies that provide the evidence about its origin. Plant remains have been obtained from the Shengjindian cemetery about 2400–2000BP, Turpan, Xinjiang, China. These records provide a information about its traditional use in ancient times, when People used stalks and inflorescence of A. annua to place in the corner of a tomb. Morphological examination of plant remains, ancient DNA extraction and further comparative analysis with modern specimens, provide the insight that these plant remains were belonging to A. annua. Further, it gives the rational insight toward its traditional use in the ancient times. This plant is strongly aromatic so local people used it with the purpose to eliminate the odor of the dead. This is the first evidence, based on the archeological studies. Several other ancient Chinese documented records also mention its numerous herbal uses. It is believed that it is not only indigenous to China but also found as native to Korea, Japan, Myanmar, Northern India, Vietnam, and Southern Siberia throughout Eastern Europe. Afterward, it spread to various other countries of North America and tropical areas (Willcox 2009; Liu et al. 2013). It wildly grows in Australia, Turkey, Iran, and Afghanistan. Now, it is commonly cultivated in Vietnam, Romania, Kenya,Tanzania (Bhakuni et al. 2001; Huang et al. 2010; Khosravi et al. 2011), Argentina, Bulgary, French, Hungary, Italy, Spain, United States, and Yugoslavia (Ferreira and Janick 2009; Lestari et al. 2011). Naturally, A. annua cover wide range of subtropical and temperate environments including northern hemisphere (mid to high latitudes). There are also very few representatives in the southern hemisphere (Ellman 2010; Das 2012). Cultivation on experimental basis in temperate and subtropical conditions has been started in India (Bhakuni et al. 2001). Breeding technique has been used to develop specific seed varieties for adapting lower latitudes, and it has been achieved successfully in various tropical countries including Congo, India, and Brazil (Willcox 2009).

  • Scientific names: Artemisia annua L.

  • Vernacular names

  • Chinese: Caohao, Cao Qinghao, Cao Haozi, Chouhao, Chou Qinghao, Haozi, Jiu Bingcao, Kuhao, San Gengcao, Xianghao, Xiang Qinghao, Xiang Sicao, Xiyehao

  • English: annual wormwood, sweet wormwood, sweet annie

  • French: armoise annuelle

  • Japanese: Kusoninjin

  • Korean: Chui-ho, Hwang-hwa-ho, Gae-tong-sook

  • Vietnamese: Thanh cao hoa vàng.

2.1.2 Pharmacognostical Studies

2.1.2.1 Macroscopic Characteristics

A. annua an aromatic annual herb with deeply grooved branches. Variation generally presents in the leaves and aerial parts. The leaves margins are not entire, but the base is asymmetrical. Leaf color varies from light green to dark green and arranged pinnately. Outer and inner surfaces are glabrous. Glandular and nonglandular trichomes are present on the both surfaces. Spongy parenchyma contains 4–6 layers of loosely arranged cells (Das 2012).

2.1.2.2 Microscopic Characteristics

Physiochemical analysis report average 9.2 w/w moisture content, 8.3 w/w total ash, 0.91 % acid insoluble ash, 6.2 w/w alcohol, and 3.8 v/w water content in A. annua. High percentage of protein, crude fat, and digestible fraction is also present in leaves and inflorescence. Plant tissue contains high amount of manganese and copper. Amino acid and vitamin profile are also very high, which increase nutritional value of this herb (Das 2012).

2.1.2.3 Chemical Constituents

A. annua has become the subject of intensive phytochemical evaluation following the discovery of the antimalarial drug artemisinin (Wang et al. 2011). Phytochemical analysis has identified various compounds including steroids, coumarins, phenolics, flavonoids, purines, triterpenoids, lipids, and aliphatic compounds, monoterpenoids (Emadi 2013; Cafferata et al. 2010; Ferreira et al. 2010), essential oils, alkaloid, and glycoside (Zanjani et al. 2012). Major terpene derivatives such as artemisia ketone (Tellez et al. 1999), artemisinic alcohol, arteannuin B, and myrcene hydroperoxide have been identified. A few of them are also present in essential oil (Verdian-rizi et al. 2008; Brown 2010). Essential oils contain both nonvolatile and volatile constituents. The volatile components of essential oils are camphene, 1-camphor, isoartemisia ketone, β-camphene, β-caryophyllene, β-pinene, artemisia ketone, 1, 8-cineole, camphene hydrate, cuminal (WHO Monographs 2006; Willcox 2009; Das 2012), Artemisia ketone, 1.8-cineole camphor, germacrene D, camphene hydrate, and alpha-pinene, betacaryophyllene, myrcene, and artemisia alcohol (Liao et al. 2006; Ferreira and Janick 2009). The nonvolatile component of essential oil contains sesquiterpenoids (Brown 2010), flavonoids and coumarins, β-galactosidase, β-glucosidase, Β-sitosterol, and stigmasterol (Willcox 2009; Cafferata et al. 2010; Das 2012). It also contains erythritol (50.30 %), camphor (7.25 %), pinocarveol (4.13 %), and diethoxyethane (2.18 %) (Haghighian et al. 2008). Scopoletin belongs to the group of coumarins that have been found in A. annua extracts (Tzeng et al. 2007). Scopoletin (coumarin), scopolin (comarin glycoside), domesticoside (phloroacetophenone), chrysosplenol-D (flavonoid), and norannuic acid (bisnor-cadinane) are vital phytoconstituents (Emadi 2013; Cafferata et al. 2010). First time, artemisinin (sesquiterpene lacton) isolated from A. annua in 1972 (Geldre et al. 2000; Ogwang et al. 2012). Artemisinin is a rare sesquiterpene lactone endoperoxide of the cadinane series (Laughlin 2002). Although there are approximately 400 species of artemisias (Ferreira 2004), artemisinin and essential oil levels in the leaves of A. annua ranged from 0.01 to 1.4 % and 0.04 to 1.9 %, respectively (Damtew et al. 2011). The leaves of A. annua are only natural source of artemisinin and other vital secondary metabolites (Table 2.1) which can be further used for the production of derivatives of pharmacological importance (Laughlin 2002; Willcox et al. 2004; Brown 2010; Cafferata et al. 2010).

Table 2.1 The phytochemical constituents of Artemisia annua L
Full size table

2.1.3 Ethnopharmacological History

Ethanopharmacological compilation named as “Fifty-two prescriptions” (dates back to 168 BC) mentioned A. annua (qinghao) as medicinal herb. This document describes it: as a remedy for hemorrhoids that resembles “cow lice” (possibly ticks). Traditional Chinese materia medica (Shennong ben cao jing), which was present in the first century AD, but now it has been lost, documented its use as food preservative, remedy for summer heat and for the treatment of “intermittent fevers”. This Handbook of Prescriptions for Emergency Treatment (Zhouhou Beiji Fang) had been documented in 340 AD, describes number of preparations as traditional medicine (Willcox 2009). Traditionally, it has been used as flavoring agent. Based on this strong traditional use and characteristic fragrance later on, it becomes the potential source for essential oils for the perfume industry (Ferreira and Janick 2009; Huang et al. 2010; Liu et al. 2013). For over 2000 years, the Chinese have used A. annua as natural remedy to treat malaria (Geldre et al. 2000; Meier zu Biesen 2010). The Pharmacopoeia of the People’s Republic of China also describes its use to cure consumptive fever and jaundice (WHO Monographs 2006; Castilho et al. 2008; Ogwang et al. 2012) wound healing and for the improvement of eye brightness (Liu et al. 2013). A. annua has also been used traditionally in Iran as medicinal plant for infants as an antispasmodic, carminative, or sedative/ hypnotic remedy (Emadi 2013; Sharma et al. 2011). A. annua decoction has been used as antihemorrhage to cure diarrhea (Mirdeilami et al. 2011). Effect of A. annua L. on hemostasis is well known in traditional medicine (Wang et al. 2011). Traditional medicinal practices involve usage of different plant parts of A. annua to cure different disease (Table 2.2).

Table 2.2 Medicinal uses of different plant parts of Artemisia annua L
Full size table

2.1.4 Pharmacological Activities

2.1.4.1 Antihypertensive Activity

Antihypertensive potential of aqueous extracts of artemisia leaves of different species, have been assessed by using in vivo models of diabetic rats and rabbits that were administered with dose of 100–390 mg kg−1 for 2–4 weeks. Results revealed the significant effects of aqueous extracts by exhibiting the reduction in blood level. Consequently, this action prevents elevation of glycosylated hemoglobin level and produces hypoliposis effect. It also causes the protective effect against body weight loss in diabetic animals. Further, it caused significant inhibition of the phenylephrine-induced contraction, and simultaneously stimulates the endothelium-dependent relaxation of rat aortic rings (Das 2012).

2.1.4.2 Antimicrobial Activity

Research studies have been carried out to evaluate antimicrobial potential of the essential oils obtained from A. annua. Experiments revealed that essential oil showed antimicrobial potential against wide range of Gram-negative bacteria, Gram-positive bacteria, and fungi. Significant inhibitory activity of the oil was found against bacterial strains, including Staphylococcus aureus, Escherichia coli, and Enterococcus hirae. Whereas Pseudomonas aeruginosa showed no sensitivity for essential oil. A. annua extracts possess remarkable antibiotic potential against fungi particularly Saccharomyces cerevisiae and Candida albicans (Juteau et al. 2002; Das 2012). Furthermore, these investigations also revealed that essential oils showed more pronounced effects against fungal strains than against Gram bacterial strains (Verdian-rizi et al. 2008). Studies based on chemical evaluation of plant extracts evidenced that phytoconstituents are responsible for conferring this antimicrobial potential. Most vital compounds that have been studied for this bioactive potential are scopoletin (Tzeng et al. 2007), sesquiterpene lactone endoperoxide artemisinin and variety of other derivative compounds. Mechanism of action these Compounds at molecular level have been studied in Escherichia coli, Mycobacterium smegmatis, and Mycobacterium tuberculosis. It has been observed that Arteether acts at nuclear level and hampers the function of DNA-gyrase which is resistant by quinolone (Kumar et al. 2003). Artemisinic acid is another well-known precursor compound used for semisynthesis of artemisinin, and it has also been studied for antibacterial activity (Bhakuni et al. 2001; Muzemil 2008; Huang et al. 2010).

2.1.4.3 Anti-inflammatory Activity

Anti-inflammatory activity of aqueous methanolic extract has been tested for acute and chronic inflammation by implying variety of inflammatory models. Aqueous extract exhibits anti-inflammatory effect in a dose-dependent manner and resulted in pronounced activity against edema. Phytochemical analysis reports the presence of number of important groups of compounds such as triterpenoids, flavonoid, polyphenols, and coumarin. Therefore, these compounds act additively and impart inhibitory potential against edema response in acute and chronic models (Das 2012). Some other research analysis also report more anti-inflammatory compounds named as scopoletin (a coumarin) (Muzemil 2008), artemisinin, dihydro artemisinin, and arteether. In vivo assays revealed that these compounds significantly inhibit the humeral responses at increased concentration. But some other studies suggest that pure compounds did not show significant efficacy in chronic hypersensitivity response (Bhakuni et al. 2001). Further experimental studies carried out on murine macrophage like RAW 264.7 cell showed the effect of scopoletin in a dose-dependent manner. Therefore, numerous research studies recommend scopoletin as a candidate for anti-inflammatory medicine (Tzeng et al. 2007).

2.1.4.4 Antioxidant Activity

A. annua is a good source of different nutritional constituents and antioxidants (Das 2012). Studies indicate that crude organic extracts of aerial parts have high antioxidant capacity which is most probably due to the fact that leaf contains high content and variety of flavonoids, including the newly reported C-glycosyl flavonoid as a possible component of the antioxidants. Flavonoids and essential oil content present in A. annua impart antioxidant potential. Therefore, these studies ranked A. annua among those medicinal plants which are at the top of list, based on their highest antioxidant potential (Juteau et al. 2002; Ferreira and Janick 2009). Major groups of hydroxylated and polymethoxylated flavonoids have been identified which further include chrysosplenol-D, cirsilineol, eupatin, chrysoplenetin, cirsilineol, casticin, and artemetin (Ferreira et al. 2010). Studies have identified respective five bioactive flavonoids and further subjected to structural analysis. These include 5-hydroxy-3,7,4′-trimethoxyflavone,5-hydroxy-6,7,3′,4′-tetramethoxyflavonol, blumeatin, 5,4′-dihydroxy-3,7,3′-trimethoxyflavone and quercetin (Yang et al. 2009).

2.1.4.5 Immunosuppressive Activity

A. annua has been evaluated for its immunosuppressive activity. Ethanolic extract of A. annua significantly suppressed concanavalin A (Con A) and lipopolysaccharide (LPS)-stimulated splenocyte proliferation in vitro and this activity increases with increase in dose. Results have also showed that ethanol extract of A. annua could suppress the cellular and humoral response (Das 2012). Immunosuppressive potential have been linked to flavonoids present in leaves which are capable to modulate the immune response (Ferreira et al. 2010).

2.1.4.6 Antiarthritis Activity

Experimental studies have revealed that artemisinin derivative SM905 (obtained from A. annua) suppresses the inflammatory and Th17 responses which cause the improvement in collagen-induced arthritis. These studies have been carried out on collagen-induced arthritis (CIA) by type II bovine collagen model (CII) in DBA/1 mice through oral administration of artemisinin derivative SM905. Incidence of disease and severity were observed regularly. Gene expression and T helper (Th) 17/Th1/Th2 type cytokine production level have also been examined. Observations of this study revealed that SM905 compound play key role as it delayed the onset of disease, hence reduce the incidence of arthritis. Furthermore, it also reduces the overexpression of variety of pro-inflammatory cytokines and chemokines (Das 2012).

2.1.4.7 Antimalarial Activity

Malaria is a global threat since long. In order to deal with this situation, it needs a coordinated approach consist of prevention strategies, therapeutic medicines, and curative treatment of patients. Therefore, extraction of artemisinins from A. annua has opened the way toward new and highly effective alternates (Ferreira 2004; Ridder et al. 2008; Ferreira and Janick 2009). A. annua L is now well recognized throughout the world (Liu et al. 2009; Willcox 2009), and currently, it is in use over 50 countries as a strong drug substitute against malaria, particularly chloroquine-resistant malaria (Ferreira et al. 2006). Studies have reported many other flavonoids (artemetin, casticin, chrysoplenetin, chrysoplenol-D, cirsilineol, and eupatorin) which possess antiplasmodial efficacy (El-feraly et al. 1989; Lubbe et al. 2012). Mechanism of methoxylated flavonoids is associated with activation of artemisinin, which explains the key role of methoxylated flavonoids, as it facilitates the interaction of artemisinin with plasmodial hemoglobin involving catabolic pathway that produces artemisinin peroxide. Furthermore, artemisinin peroxide inhibits the heme polymerization and ultimately confers the antimalarial effects against protozoan Plasmodium species: falciparum vivax, malariae, and ovale. Another mechanism of flavonoids suggests that it blocks the incorporation of hypoxanthine by Plasmodium (Laughlin 2002; Muzemil 2008; Das 2012). Although artemisinin induce antiplasmodial effects through alkylation of malarial-specific proteins (Bhakuni et al. 2001), some flavonoids had no specific antiplasmodial activities but had capability to potentiate antiplasmodial activity of artemetin (Ferreira et al. 2010). In early 1970s, Chinese scientists have selected artemisinin, artemether, and sodium artesunate for clinical evaluation. There are studies in which malarial patients (more than 3000) were clinically subjected to the treatment by artemisinin and its derivatives. These results suggest more curative potential of artemisinin compounds particularly against drug-resistant P. falciparum (Mueller et al. 2000; Weathers and Towler 2012). Comparative clinical studies have been conducted to evaluate the efficacy of whole herb of A. annua and chloroquine. Organic extracts A. annua have been found more effective, faster, and less toxic than chloroquine in treating malaria (Huang et al. 2010; Tayebe et al. 2012). It significantly reduces parasitemia and improves the immune response by stimulating phagocytic activity of macrophages. Whole plant extract activity is more pronounced because of the presence of various phytoconstituents that impart synergistic antimalarial potential. Therefore, it is quite obvious that current combinatorial approach may be representing the formulations of phytoconstituents (and sometimes plant species) that confer synergistic effect, as they are present in the herbal prescriptions (Willcox 2009; Donno et al. 2012).

2.1.4.8 Antiparasitic Activity

Research studies suggest that artemisinin drugs have good antiparasitic potential for Leishmania, Trypanosoma Babesia, Eimeria or coccidiosis, trematodal blood fluke Schistosoma spp., and Schistosoma japonicum, Schistosoma mansoni, and Schistosoma haematobium. Therefore, currently, its use in livestock industry has been increasing (Kumar et al. 2003; Ferreira and Janick 2009). A study has been conducted against Neospora canum, which is a protozoal parasite of mammals. Cultured Vero cells or mouse peritoneal macrophages were infected with of Artemisinin for 14 days. All microscopic foci of N. caninum completely eliminated at 20 or 10 μg/ml after 11 days, and same results were obtained at concentration of 0.1 μg/ml. Therefore, artemisinin has potential to reduce the intracellular multiplication of N. caninum tachyzoites. In another study, the effect of artemether was tested against the larval stages of Schistosoma mansoni. It has been found that animals did not develop schistosomiasis after artemether treatment. Susceptibility of parasite was quite pronounced as compared to the nontreated controls (Das 2012). Recently, another research study reports that n-hexane extracts of A. annua leaves and seeds exhibit significant activity against Leishmania donovani. This antileishmanial activity includes morphological changes in promastigotes, apoptosis, and cell-cycle arrest at cellular level (Islamuddin et al. 2012).

2.1.4.9 Anticancer Activity

A. annua is well known by its pharmacological applications in the popular medicines, and currently it is a subject of research studies with the aim to find the treatment against cancer (Cafferata et al. 2010). Anticancer activity of various organic extracts of A. annua has been evaluated by determining their cytotoxic potential in Trypanosoma b. brucei (TC221 cells) and HeLa cancer cells. These evaluations showed that methanol extracts are more cytotoxic as compared to dichloromethane extracts (Efferth et al. 2011). Cytotoxicity studies of artemisinin and quercetagetin-6, 7, 3¢, 4¢-tetramethylether against various tumor cells including P-388, A-549, Ht-29, KB, and MCF-7 cells showed significant efficacy (Bhakuni et al. 2001; Muzemil 2008). In vitro and in vivo anticancer testing exhibits promising results of artemisinins, and further investigations reveal its mechanism of action, which provides an insight toward its constitutional property that is built in its structure. Artemisinin contains an endoperoxide group that imparts anticancer activities. Like some other compounds such as hydrogen peroxide, artemisinin reacts with ferrous iron and make free radical species. These free radicals trigger anticancer activities. Further extended research investigations report that these anticancer activities become more pronounced upon addition of iron complexes in cell culture. Artemisinin makes covalent conjugate with transferrin (an iron transport protein, found in human) so this artemisinin and transferrin conjugate actively transported inside the cancer cells by the involvement of transferrin receptor (TfR)-mediated endocytosis pathway and result in pronounced anticancer activity experimental cell cultures. This also explains the importance of iron metabolism that enhances the anticancer potential of artemisinin. In addition, artemisinin and its derivatives induce programmed cell death in cancer cells through activation of cytochrome C-mediated pathway which lead toward apoptosis (Ferreira et al. 2010). Therefore, several research investigations established artemisinin as s potent anticancer agent (Huang et al. 2010; Nadeem et al. 2013) and recommend it against cancer as drug therapy (Ferreira and Janick, 2009; Ferreira et al. 2010; Zanjani et al. 2012). Chemical and structural characteristics also recommend it as a lead compound, which can further become the basis of drug development (Bhakuni et al. 2001). Research studies have also identified some other vital compounds which possess antitumor activity such as scopoletin (Tzeng et al. 2007), artemisinin and its derivatives (Kumar et al. 2003).

2.1.4.10 Angiotensin Converting Enzyme Inhibitors

Studies have identified few flavonoid compounds from A. annua such as fisetin and patuletin-3, 7-dirhamnoside, which exhibit the potential for blocking nonpeptide angiotensin converting enzyme (Bhakuni et al. 2001; Muzemil 2008).

2.1.4.11 Antiviral Activity

Antiviral activity of A. annua tea infusions against HIV has been evaluated very first time through scientific investigation. Two independent cellular systems have been used for toxicity studies. The A. annua tea infusion exhibits highly significant activity at very low concentration (2.0 μg/mL). But artemisinin was found inactive at higher concentration (25 μg/mL). Similarly, no cellular cytotoxic effects were observed at higher concentration of tea infusion. Therefore, this in vitro study revealed that artemisnin plays limited role and may act synergistically against anti-HIV activity (Lubbe et al. 2012). Some other in vitro studies have claimed about inhibitory effects for hepatitis B virus (WHO Monographs 2006). Currently, artemisinin and its derivatives has become the subject of scientific studies to investigate their potential against number of viruses (Ferreira and Janick 2009) with the aim of advanced combination therapies of antivirals (Weathers and Towler 2012).

2.1.4.12 Plant Growth Regulatory Activity

Research studies report that A. annua contain series of vital compounds that have the potential to regulate the plant growth activities and some of them act as natural pesticides. These compounds have also been recommended as natural pesticide in agriculture. These compounds are bis (1-hydroxy-2-methylpropyl) phthalate, abscisic acid, and abscisic acid methyl ester, artemisinin, and its derivatives (Bhakuni et al. 2001).

2.1.4.13 Antifeedant Properties

Research studies have been conducted by implying various parameters of assessment of antifeedant activity for crude extracts of A. annua. Deterrency, growth regulatory effect and ovicidal potential strongly recommend it as a good antifeedant herb (Haghighian et al. 2008), as antihelminthes and anti-insecticidal agent (Khosravi et al. 2011; Vicidomini 2011). Some studies have reported that crude extracts of A. annua contain artemisinin and its derivatives which act as natural pesticide (WHO Monographs 2006; Huang et al. 2010; Weathers et al. 2011).

2.2 Conclusion

A. annua is ethanomedicinally important plant as its medicinal use has been well established in Chinese pharmacopeias since 168 BC A. annua has also obtained an important place among plant-based advanced therapeutics. Particularly against drug-resistant malaria, it has become a good hope for treatment, because it has very low toxicity. Mefloquine is one of the antimalarial drug, but it is associated with multiple side effects. Recent several research studies have revealed that A. annua possess characteristic biological activities to cure various diseases. But their mechanisms of action at cellular and molecular level still need to be investigated. A. annua is a rich source of large number of biologically active phytoconstituents, and particularly, it is the only source of artemisinin. It possesses characteristic therapeutic potential against malaria, and besides antimalarial effects, it has various other biological activities such as anti-inflammatory, antibacterial, angiotensin converting enzyme inhibitory, cytokinin-like, and antitumor activities. Nowadays, there is increasing research focus toward investigation of its anticancer and antiviral effects particularly for HIV/AIDS. Therefore, mechanisms of action of the active phytoconstituents particularly artemisinin and their derivatives has become the emerging area of interest in the arena of scientific investigations. These research studies can validate the ethanomedicinal use of A. annua by local community on scientific bases. Therefore, A. annua is a strong alternate which can be widely explored and finally can lead toward drug development.