Artemisia vulgarisL., is a perennial wild herb belonging to Artemisia family. Mugwort is a traditional Chinese medicine in our country. It is recorded in the medical books of the past dynasties as a "necessary medicine for hemostasis" and is one of the common drugs used in gynecology.

Mugwort has the functions of warming the channels, stopping bleeding, dispelling cold and relieving pain, regulating the channels and calming the fetus, removing dampness and relieving itching, and activating the channels and collaterals. Although the medicinal plant has been used in folk practice for thousands of years, the scientific analysis and utilization of the medicinal ingredients of mugwort began in modern times. In recent years, there have been many reports on the pharmacognosy, chemical composition, pharmacological action, clinical application, technology and quality control of mugwort. In this paper, the research status of mugwort in chemical composition and pharmacological action is summarized as follows.

1 Chemical composition study

The medicinal part of mugwort is mugwort leaf, and the medicinal function of mugwort leaf comes from the chemical substances contained in it. The chemical components of mugwort mainly include volatile oil, flavonoids, eudesane, triterpenoids and trace chemical elements.

1.1 Volatile oils 

The volatile oil content of Artemisia mugwort was 0.20% ~0.33%. In 1985, Zhu Liangfeng et al. reported for the first time the chemical composition of the volatile oil of Artemisinin. There were nearly 40 components (39.45%) of the volatile oil with 1, 8-cineulin as the main compound, mainly α-thujene, pinene, camphene, sabinene, 1-octene-3-ol, p-cymarin, 1, 8-cineulin, y-terpinene, camphor, and camphor. Pan Jiongguang et al. identified 60 components, such as 2-methylbutanol, 2-hexenal, tricyclic terpene and a-pleutene, from wormwood leaves. Liu Guosheng identified 34 components from the volatile oil of wild mugwood leaf produced in Laoshan, Shandong province, among which limonene, α-pleujujuone, α-cresine and citronellol were the highest content. The main components and contents of volatile oil of Artemisia mugwormwood and Artemisia mugwormwood leaves were different in various reports, which may be closely related to the growing region, environment, climate, and material collection time.

1.2 Flavonoids

Artemisia flavonoids mainly consist of 5, 7-dihydroxy-6,3, 4-trimethoxy-flavonoid (eupatilin), 5-hydroxy-6,7,3, 4-tetramethoxy-flavonoid, quercetin and naringenin.

1.3 Eudesanes

eudesmane consists of cryptomerediol, Artemisone, 1-ox4β-acetoxy-eudesin-2.11 (13) -diene-12, 8βlactone, 1-ox4a-acetoxy-eudesin-2,11(13) -diene-12, 8β-lactone.

1.4 Triterpenoids

Triterpenoids include a- and β-balsaminol, amylterpene, alpha - and β-balsaminol acetate, lupenone, mucilenone, fernenone, 24-methylenocyclobromelanone, 3-β-methoxy-9B, 19-cyclolanostere-23 (E) ene-25, 26-diol, etc.

1.5 Trace chemical elements

By atomic absorption spectrometric mugwort was found to contain a variety of trace elements, such as strontium (Sr), chromium (Cr), cobalt (Co), nickel (Ni), manganese (Mn), copper (Cu), zinc (zinc), iron (Fe), sodium (Na), potassium (K), calcium (Ca), magnesium (Mg), etc.

1.6 Other chemical components

Other chemical components of Artemisia argyi mainly include β-sitosterol, stigasterol, ethyl palmitate, ethyl oleate, ethyl linoleate and trans-phenylmethylene succinic acid.

2 Pharmacological Research

2.1 Antibacterial effect

Artemisia mugwort can inhibit Bacillus anthracis, hemolytic streptococcus A, hemolytic streptococcus B, diphtheria bacillus, diplococcus pneumoniae, Staphylococcus aureus and Bacillus subtilis in vitro. The aqueous extract of Artemisia argyi leaves has an inhibitory effect on common pathogenic skin fungi. Wormwood leaves have obvious antibacterial effect on the affected area, which reduces the number of bacterial colonies in the air and completely inhibits the growth of pyogenic bacteria. Moxa stick smoking can also reduce the bacteria on the burn wound. After moxibustion treatment of tuberculosis in guinea pigs, the disease progresses slowly and the lesions are mild, especially in the later stages of the disease. In addition, it can enhance the phagocytosis of reticuloendothelial cells. The ancient people used mugwort leaves to control dysentery and the folk used mugwort leaves to drive away evil, which corresponded to the strong antibacterial effect of mugwort leaves.

2.2 Anti-cancer effect

Mugwort leaf has the effect of anti-digestive tract tumor and breast cancer, and mugwort leaf oil can enhance the phagocytic ability of inflammatory exudate cells and the phagocytic response of reticuloendothelial cells in mice.

2.3 Gallbladder effect

Duodenal administration of mugwort oil suspension at 8ml/kg and 3ml/kg could increase the bile flow of normal rats by 91.5% and 89%, compared with that before administration

Very significant difference (P<0.001). Duodenal administration of 0.02ml/kg mugwort oil can increase the bile flow of normal mice by 20%, indicating that it has obvious gallbladder effect.

2.4 Antiasthmatic, antitussive, expectorant effects

Artemia mugwort volatile oil has antitussive, antiasthmatic and expectorant effects, among which the main active ingredient is terpenenol, which directly acts on the trachea, can relieve asthmatic asthma and expectorate phlegm, regulate the center, and has obvious protective effect on drug-induced asthma, and can prolong the asthma induction latency of acetylcholine plus histamine, and reduce the number of convulsive animals. Intragastric administration of 300mg/kg 4-terpinenol derived from mugwort also had significant antiasthmatic effect. Gavage 1ml/kg of Artemisia argyi oil had obvious expectorant effect on phenol red method in mice. The volatile oil component 4-terpinenol or syringene intraperitoneally injected with 1ml/kg or 0.7ml/kg also had expectorant effects. Administration of 0.05ml/kg A-terpinol has protective effect on asthma induced by inhalation of acetylcholine and histamine in guinea pigs, and trans-miroferol is also an effective component of asthmatics.

2.5 Hemostasis and anticoagulation

Zhang Xuelan et al. studied the effect of processing on the main components and hemostatic effect of Artemisia argyi leaves, and the results showed that the volatile components content of Artemisia argyi leaves decreased significantly after heating processing. After frying charcoal or drying, it has significant effect on coagulation and bleeding time of mice, and has obvious hemostatic effect. The ethanol extract of Artemisia argyi had obvious inhibitory effect on ATP-induced platelet aggregation. Pharmacological studies of leaves show that Artemisia argyi plays a hemostatic role by reducing capillary permeability and resisting fibrinolysis. This is consistent with the ancient people's use of moxa leaf to treat menorrhagia, disintegrating leakage, hematochezia and other blood syndromes.

2.6 Anti-allergic effect

Studies have shown that 2-terpenenol and carynol in mugwort oil can inhibit the skin blood vessels caused by passive skin allergic reaction and 5-hydroxytryptamine in rats

Enhanced permeability inhibits the release of SRS-A from guinea pig lung tissue and causes guinea pig ileum contraction by SRS-A. Trans-carynol also inhibited Sc-hultz-Dale reaction in isolated trachea of guinea pigs.

2.7 Effects on the nervous system

Artemsia argyi oil has obvious sedative effect, can prolong the sleep time of pentobarbital, but can accelerate the convulsive death of strychnine, which seems to have a certain synergistic effect. In addition, large doses have an inhibitory effect on the heart, and can protect the anaphylactic shock caused by egg albumin in guinea pigs.

2.8 Effects on the cardiovascular system

Mugwort oil can inhibit the contractility of isolated toad heart and isolated rabbit heart. Mugwort oil can counteract the contractility induced by adrenaline and histamine. Studies have shown that 1-2 drops of mugwort oil with a concentration of 1:50 can significantly inhibit the contractility of the heart, which has little effect on the heart rate, but can cause atrioventricular block. For example, increasing the concentration can cause cardiac arrest. For isolated rabbit hearts, 1ml mugwort oil (1:150) can inhibit the contractility of the heart, significantly reduce the heart rate and coronary flow, and increase the tension of the rabbit aorta It has a relaxing effect and can counter the cardiotonic effect of isoproterenol.

2.9 Absorption, excretion, toxic effects

Mugwort leaf and its preparations are absorbed by the mucosa of small intestine and reach the liver soon after oral administration, and then spread to the whole body with blood circulation. Mugwort components can be found in urine within 1h, most of which are stored in the body and gradually excreted by urine, or destroyed by oxidation or combination. In addition, the volatile oil of mugwort is mildly irritating to the skin, which can cause fever and flushing. A small amount of 3~5g orally can increase appetite, and a large amount can cause acute inflammation of the gastrointestinal tract.

Mugwort is a kind of multifunctional plant with medicine and food, which is distributed all over the country. It has rich drug source, low toxicity, low price, and wide development and utilization value. Human research and development of mugwort is still very limited, the chemical composition of mugwort is still significant to make mugwort leaf more widely used in clinic.