Ailanthus species (Simaroubaceae) have a history of use in traditional medicine, particularly for the treatment of dysentery, A. altissima is particularly noted as an antibacterial, anthelmintic, amoebicide and insecticide (); A. excelsa () is noted as a specific for respiratory problems and A. malabarica is noted for the treatment of dyspepsia, bronchitis, opthalmia and snake bite.
Ailanthus altissima: Distribution and Importance
A. altissima Mill. Swingle. (Syn. A. glandulosa Desf.) originated in China, where it has been used in traditional medicine for enteritic infections of various origins (American Herbal Pharmacology Delegation 1975). Throughout the Far East, various parts of A. altissima are considered to be medicinal, with the use of either the fruits or bark of either root or stem for dysentery and various other gastric and intestinal upsets. Trees harvested for medicinal purposes are usually felled in the spring or autumn, and the bark is removed and dried in the sun. It is normally used to make aqueous extracts which are bitter, astringent and cooling. Bark extract has also been used to treat anaemia and as a taeniafuge, but does not have vermifuge properties. Leaves are toxic to domestic animals, causing inflammation to the digestive tract; gardeners cutting the trees may suffer erupting pustules. The bark is reported to contain an oleoresin, a bitter essence, an aromatic essence, a resin, some mucilage, ceryl alcohol, ailanthin, calcium oxalate and isoquercetin. A. altissima, also known as the “Tree of Heaven”, has been introduced into a number of other countries, i.e., India, Japan, and northern Australia, and, more recently, has been established as an ornamental tree in cities throughout Europe and North America, where it has gained popularity due to its general compact habit, small deciduous leaves and colorful autumn fruits.
Ailanthus altissima: Conventional Practices in Propagation and Growing
A. altissima is a large deciduous, dioecious tree which is frequently 50-70 feet high with a trunk 2-3 feet in diameter. It has a rounded head of branches and the older bark is marked with numerous grey fissures. Leaves are pinnate, 1-1.5 feet long with 15-30 leaflets; the leaves of the male plant have a typical foetid odor. Leaflets are 3-6 inches long, ovate, with the margin almost entire. Flowers are in terminal pannicles. The fruits consist of three to five keys (similar to those of the ash tree), which form attractive orange to red clusters in August and September. A ilanthus has proved to be an excellent tree for planting in towns for its display of large pinnate leaves, its colorful autumn fruits and particularly for its tolerance to city pollution. The plant is usually cultivated either from ripe seed (February/March) or from suckers (March/April), which thrive in any fairly good soil. Since it is preferable to produce female plants which do not have the undesirable foetid odour, propagation from root cuttings is the more popular method. Cutting young trees back to the ground in the spring and reducing the young shoots to a single shoot helps to produce a tree with strong wood and large (4-foot) leaves.
Ailanthus altissima: Recent Medicinal Interest in the Biological Activity of the Constituents
Phytochemical investigations into the compounds, isolated from A. altissima, with biological activities have focussed on the quassinoids, which are considered to be degraded terpenes. Ailanthone is the major constituent and more than 20 other quassinoids have now been isolated from the whole plant. The quassinoids isolated from A. altissima have demonstrated biological activity. In regard to the traditional use of aqueous extracts of bark and fruit in the treatment of dysentery, the major quassinoid constituent, ailanthone, has potent antiamoebic activity against Entamoeba histolytica both in vitro and in vivo. More recently, other quassinoid constituents of A. altissima have also been shown to be active with the following IC50 (μg/ml) ailanthone (0.04), ailanthinone (0.06), and glaucarubinone (0.025) as compared with a standard amoebicide, metronidazole (0.35).
The current use of Ailanthus altissima in Europe and North America is principally as an ornamental tree, particularly in cities, where it withstands pollution well. In Asia, extracts of A. altissima bark and fruits are used as an antimicrobial, anthelmintic, and amoebicide. The biological activities of the quassinoids and canthin-6-one alkaloids isolated from this plant confirm uses in traditional medicine and interest in this plant continues as a result of these biological activities, which make some of these constituents of potential use as templates for new drugs. As a result, research continues on efforts to produce plant cell cultures of A. altissima high yielding in the quassinoid ailanthone and in the canthin-6-one alkaloids, since the yield of both these products from the mature plant is very low.
Medicinal and Aromatic Plants III (1991)