Thursday, April 24, 2008

Angelica-----Herb.

SCIENTIFIC NAME : Angelica archangelica

COMMON NAME : European Angelica, Echt engelwurz (German)

BOTANY

Angelica is a widely cultivated, aromatic biennial, northern European herb with fleshy, spindle-shaped roots, an erect stalk, and many greenish-yellow flowers arranged in an umbel. The seeds are oblong and off­white. It is similar to and sometimes confused with the extremely toxic water hemlock, Cicuta maculata.

HISTORY

Angelica has been cultivated as a medicinal and flavoring plant in Scandinavian countries since the 12th century and in England since the 16th century. The roots and seeds are used to distill about 1% of a volatile oil used in perfumery and as a flavoring for gin and other alcoholic beverages. The candied leaves and stems are used to decorate cakes. The oil has been used medicinally to stimulate gastric secretion, treat flatulence, and topically treat rheumatic and skin disorders.

CHEMISTRY

The volatile oil contains many monoterpe­nes; 3-phellandrene is the principal component of var angelica, while sabinene is the most abundant monoter­pene of var. sativa. Sesquiterpenes are also numerous in the oil; a-copaene and other tricyclic sesquiterpenes are characteristic constituents.

Supercritical fluid extraction has been studied as an alternative method of extracting angelica volatiles? The shelf life of the root is limited because of the loss of the volatile oil while in storage.

The small organic acid, angelic acid, was the first com­pound purified from the root inpentadecanolide (Exaltolide) is a fatty acid lactone constituent of the root with a musk-like odor, used as a fixative in perfumes.

As with most of the many species of angelica, A. arch­angelica contains a wide variety of coumarins and their glycosides. The angular furanocoumarins, archangelicin6 and angelicin, and congeners are present in the roots, and many glycosides and esters of linear furanocou­marins have also been reported.

A trisaccharide, umbelliferose, was originally isolated from angelica roots.

PHARMACOLOGY

Angelic acid was formerly used as a sedative. The angular furanocoumarin angelicin has also been reported to have sedative properties, although recent experimental evidence of this is limited. The car­minative action of the volatile oil is because of an unre­markable monoterpene content. Angelica root oil was preferentially relaxant on tracheal smooth muscle prepa­rations compared to ileal muscle.1o The oil had no effect on skeletal muscle in a second study.

The calcium­blocking activity of angelica root has been examined relative to solvent used in extraction, and furanocou­marins were identified as the likely active species. The root oil has been found to have antifungal and antibacte­rial activity.

INTERACTIONS

Theoretically, based on additive or synergistic effects because of coumarin or coumarin derivatives possibly present in angelica root, there is a possible increased risk of bleeding when using angelica root concurrently with warfarin. Because warfarin has a narrow therapeutic index, it would be prudent to avoid concurrent use.

TOXICOLOGY

The linear furanocoumarins are well­known dermal photosensitizers, while the angular furano­coumarins are less toxic. The presence of linear fura­nocoumarins in the root indicates that the plant parts should be used with caution if exposure to sunlight is expected. The coumarins are not important constituents of the oil, which therefore gives the oil a greater margin of safety in that respect. However, poisoning has been recorded with high doses of angelica oils.

SUMMARY

Angelica and its oils have been used as digestive aids for many years in Europe. At high doses, the oils can be toxic, and furanocoumarins in the plant can cause photodermatitis.

Angelica root is official in the German and Austrian pharmacopoeias and is listed as approved in the German Commission E monographs for GI disorders, although the leaf and seed are unapproved. It was official in the United States Pharmacopeia and the National Formulary from 1820 to 1936. It is monographed in the British Herbal Pharmacopeia, and in the WHO Selected Medici. nal Plants . An American.

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