Astragalus

Astragalus
A. lentiginosus
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Angiosperms
Clade:	Eudicots
Clade:	Rosids
Order:	Fabales
Family:	Fabaceae
Subfamily:	Faboideae
Tribe:	Galegeae
Subtribe:	Astragalinae
Genus:	Astragalus L.
Type species
Astragalus onobrychis L.
Species
Over 3,000 species, see List of Astragalus species
Synonyms
Acanthophaca Nevski Acanthyllis Pomel Ailuroschia Steven Alopecias Steven Ammodytes Steven Anaphragma Steven Ankylobus Steven Astenolobium Nevski Astracantha Podlech Astragalina Bubani Astragaloides Adans. Atelophragma Rydb. Aulosema Walp. Barnebyella Podlech Batidophaca Rydb. Brachyphragma Rydb. Caryolobium Steven Chondrocarpus Steven Cnemidophacos Rydb. Contortuplicata Medik. Craccina Steven Cryptorrhynchus Nevski Ctenophyllum Rydb. Cymbicarpos Steven Cystium Steven Cystopora Lunell Didymopelta Regel & Schmalh. Diholcos Rydb. Dipelta Regel & Schmalh. Diplotheca Hochst. Euilus Steven Euprepia Steven Feidanthus Steven Geoprumnon Rydb. Glandula Medik. Glaux Hill Glottis Medik. Glycyphylla Steven Gynophoraria Rydb. Halicacabus (Bunge) Nevski Hamaria Fourr. Hamosa Medik. Hedyphylla Steven Hesperastragalus A.Heller Hesperonix Rydb. Hippomanica Molina Holcophacos Rydb. Homalobus Nutt. Hypoglottis Fourr. Jonesiella Rydb. Kentrophyta Nutt. Kirchnera Opiz Lithoon Nevski Lonchophaca Rydb. Macrosema Steven Medyphylla Opiz Microphacos Rydb. Myctirophora Nevski Myobroma Steven Neodielsia Harms Oedicephalus Nevski Onix Medik. Onyx Medik. Ophiocarpus (Bunge) Ikonn. Orophaca Britton Oxyglottis (Bunge) Nevski Pedina Steven Phaca L. Phacomene Rydb. Phacopsis Rydb. Philammos Steven Physondra Raf. Picraena Steven Pisophaca Rydb. Podlechiella Maassoumi & Kaz.Osaloo Podochrea Fourr. Poecilocarpus Nevski Proselias Steven Psychridium Steven Pterophacos Rydb. Rydbergiella Fedde & Syd. ex Rydb. Saccocalyx Steven Sewerzowia Regel & Schmalh. Solenotus Steven Stella Medik. Tium Medik. Tragacantha Mill. Triquetra Medik. Xerophysa Steven Xylophacos Rydb.

Fruits and seeds of Astragalus hamosus

Astragalus is a large genus of over 3,000 species of herbs and small shrubs, belonging to the legume family Fabaceae and the subfamily Faboideae. It is the largest genus of plants in terms of described species. The genus is native to temperate regions of the Northern Hemisphere. Common names include milkvetch (most species), locoweed (in North America, some species) and goat's-thorn (A. gummifer, A. tragacantha). Some pale-flowered vetches (Vicia spp.) are similar in appearance, but they are more vine-like than Astragalus.

Description

Most species in the genus have pinnately compound leaves. There are annual and perennial species. The flowers are formed in clusters in a raceme, each flower typical of the legume family, with three types of petals: banner, wings, and keel. The calyx is tubular or bell-shaped.

Taxonomy

The genus was formally described in 1753 by Carl Linnaeus in his Species Plantarum.

The name Astragalus is Greek, an old name for this group of plants which were believed to have a positive effect on goat milk production.

Selected species

Ecology

Astragalus species are used as food plants by the larvae of some Lepidoptera species including many case-bearing moths of the genus Coleophora: C. cartilaginella, C. colutella, C. euryaula, and C. onobrychiella feed exclusively on Astragalus, C. astragalella and C. gallipennella feed exclusively on the species Astragalus glycyphyllos, and C. hippodromica is limited to Astragalus gombo.

Uses

Traditional medicine

Astragalus has been used in traditional Chinese medicine over centuries to treat various disorders, but there is no high-quality evidence that it is effective or safe for any medical purpose.

Phytochemicals and supplements

Extracts of astragalus root include diverse phytochemicals, such as saponins and isoflavone flavonoids, which are purported in traditional practices to increase lactation in nursing mothers. There is no valid clinical evidence to indicate such use is effective or safe for the mother or infant.Dietary supplement products containing astragalus extracts may not have been adequately tested for efficacy, safety, purity or consistency. The root extracts of astragalus may be used in soups, teas or sold in capsules.

Side effects and toxicology

Although astragalus supplements are generally well tolerated, mild gastrointestinal upset, diarrhea, and allergic reactions may occur. Because astragalus may affect regulation of blood sugar and blood pressure, it may be risky for people with blood disorders, diabetes, or hypertension to use it as a supplement. Astragalus may interact with prescribed drugs that suppress the immune system, such as medications used by people being treated for cancer or recovery from organ transplants.

Some astragalus species can be toxic, such as those found in the United States containing the neurotoxin swainsonine, which causes "locoweed" poisoning in animals. Some astragalus species may contain high levels of selenium, possibly causing toxicity.

Ornamental use

Several species, including A. alpinus (bluish-purple flowers), A. hypoglottis (purple flowers), and A. lotoides, are grown as ornamental plants in gardens.

External links

Wikimedia Commons has media related to Astragalus.

• Astragalus — Genus of vascular plants
• Astragalus – Clinical summary and constituents, MSKCC Memorial Sloan Kettering Cancer Center