Common Name: Cowitch

General Information

Mucuna pruriens is very variable in habit, ranging from an annual to a short-lived perennial or a climbing shrub producing slender, climbing, semi-woody stems that are usually 1 - 6 metres long[]. These stems scramble over the ground, or twine into other plants for support. The plant is sometimes stated to climb to the tops of tall trees[].
The plant is harvested from the wild for local use as a food and a medicine. It is cultivated in parts of the tropics as a medicinal plant and for its content of L-DOPA, which is used by the pharmaceutical industry, and is also grown as a green manure to improve the soil. It is also used for grazing animals, though the irritant hairs on the seed pods restrict this use somewhat.

Known Hazards

The seed pods are covered with reddish-orange irritant hairs that are readily dislodged and can contaminate clothes or other objects. The hairs act as a mechanical-chemical skin-irritant and, even Mucuna species in general possess irritant hairs on the leaves, seedpods etc. These hairs consist of 1-2 small basal cells and a large needle-like top cell. The top cell breaks off easily, piercing the skin and injecting chemical compounds that are present in the hairs. The proteolytic enzyme 'Mucunain' is said to be the active agent[].
The hairs can contaminate clothes or other objects, and remain active when dried, though they can be destroyed by heat[, , ]. Intense itching, with reddening of the skin and small papules or urticaria occur a few minutes after contact with the hairy parts of the plant. There is no serious danger, unless the hairs get into the eye, in which case, in extreme situations, they have caused blindness. To remove the hairs from the skin, adhesive tape and washing with water and soap are considered useful. Dermatitis can be treated with corticosteroid ointment. See a doctor immediately if hairs go into the eyes[].

The seed contains a range of anti-nutritive substances and can be toxic for human and non-ruminant animal consumption. The most important toxic compounds are the non-protein amino acids L-dopa (content in seeds <2% - >7%) and hallucinogenic tryptamines[]. Furthermore, trypsin-inhibiting activities have been detected in the seed[].

Botanical References

Range

Tropical Africa - Senegal to Somalia, south to Angola, Zambia, Zimbabwe, S. Africa; E. Asia - India, Myanmar, Thailand, Malaysia to New Guinea.

Habitat

Primary and secondary forests, monsoon forest, grasslands, along hedges and fields, along rivers,
at the sea coast, along roads[].

Properties

Weed Potential	Yes
Edibility Rating
Medicinal Rating
Other Uses Rating
Habit	Annual/Perennial
Height	4.00 m
Pollinators	Self
Self-fertile	Yes
Cultivation Status	Cultivated, Wild

Cultivation Details

A plant of the hot and humid tropics, where it is found at elevations up to 2,100 metres. It grows best in areas where annual daytime temperatures are within the range 20 - 30°c, but can tolerate 10 - 34°c[]. Young growth can be severely damaged at 5°c[]. It prefers a mean annual rainfall in the range 1,000 - 2,000mm, but tolerates 400 - 3,100mm[].
Prefers a well-drained, moist, humus-rich soil and a position in full sun or partial shade[]. Found in the wild on sandy soils, loams, limestone, and volcanic soil.s[]. Prefers a pH in the range 5 - 7, tolerating 4 - 8[]. Established plants are drought tolerant[].
The plant can grow in a range of habitats and could become naturalised in grasslands, bushland, riverine forest and forest edges throughout tropical and subtropical regions. It can form woody thickets and smother underlying vegetation. It has been classified as 'Invasive' in some Pacific Islands, in Indonesia and in Thailand[].
The plant can mature a crop of seeds within 100 - 130 days in N. America and 210 - 270 days in the tropics[].
In India seed yield are reported to average between 0.7 - 1.1 tonnes per hectare[]. Yields of seed up to 3.3 tonnes can be obtained[].
There are numerous cultivars of Mucuna pruriens, some of which were formerly treated as separate species[].
This species has a symbiotic relationship with certain soil bacteria, these bacteria form nodules on the roots and fix atmospheric nitrogen. Some of this nitrogen is utilized by the growing plant but some can also be used by other plants growing nearby[]. When removing plant remains at the end of the growing season, it is best to only remove the aerial parts of the plant, leaving the roots in the ground to decay and release their nitrogen.

Edible Uses

The seeds are a common famine food, made edible by boiling them in several changes of water[, ].
The immature seedpods and the seeds in them are soaked then cooked and eaten as a vegetable or are mixed with salt and taken as a snack[, , ].
Mature seeds can be ground into a flour or roasted and used as a coffee substitute[].

Medicinal

Cowitch has a long history of medical use, with records of it being used in Ayurvedic medicine over 2,000 years ago[]. It is an irritant, rubefacient herb that destroys internal parasites, is diuretic and aphrodisiac[]. The seeds of the plant are a source of the substance L-DOPA, which revolutionized the treatment of Parkinson's Disease in the 1960's[]. The seeds also contain hallucinogenic toxic compounds[].

The roots are diuretic and purgative[, , ]. They are used internally in the treatment of paralysis, nervous complaints, cholera and kidney problems[, ]. Externally, they are used in the treatment of elephantiasis and dropsy[]. The roots are harvested as required and can be dried for later use[].

The irritant hairs on the seedpods are taken internally in the treatment of roundworms[, ]. Great care should be taken in this treatment - the irritant hairs can be fatal if taken in excess[]. The seedpods are harvested when ripe and the hairs scraped off[]. These are dried, powdered then mixed with treacle, honey or added to ointments[, ].

The seeds are aphrodisiac[].

A vinous tincture of the pods was formerly used in the treatment of dropsy[].

Agroforestry Uses:

The plant can be grown as a ground cover and green manure, being able to suppress vigorous weeds like Imperata cylindrica[].

Other Uses

None known

Propagation

Seed -

Add a Comment:

If you have any useful information about this plant, please leave a comment. Comments have to be approved before they are shown here.

Name:

Email(Private):

Message:

Captcha: what is half of 100?