''Mucuna pruriens'' is a tropical

legume A legume () is a plant in the family Fabaceae (or Leguminosae), or the fruit or seed of such a plant. When used as a dry grain, the seed is also called a pulse. Legumes are grown agriculturally, primarily for human consumption, for livestock fo ...

native to

Africa Africa is the world's second-largest and second-most populous continent, after Asia in both cases. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 6% of Earth's total surface area ...

and tropical Asia and widely naturalized and cultivated. Its English

common name In biology, a common name of a taxon or organism (also known as a vernacular name, English name, colloquial name, country name, popular name, or farmer's name) is a name that is based on the normal language of everyday life; and is often contra ...

s include monkey tamarind, velvet bean, Bengal velvet bean, Florida velvet bean, Mauritius velvet bean, Yokohama velvet bean, cowage, cowitch, lacuna bean, and Lyon bean. The plant is notorious for the extreme itchiness it produces on contact, particularly with the young foliage and the seed pods. It also produces many medium-sized red swollen bumps along with the itching. It has agricultural and horticultural value and is used in

herbalism Herbal medicine (also herbalism) is the study of pharmacognosy and the use of medicinal plants, which are a basis of traditional medicine. With worldwide research into pharmacology, some herbal medicines have been translated into modern remedie ...

Description

''Mucuna pruriens'' is an annual climbing shrub with long vines that can reach over in length. When the plant is young, it is almost completely covered with fuzzy hairs, but when older, it is almost completely free of hairs. The leaves are tripinnate, ovate, reverse ovate,

rhombus In plane Euclidean geometry, a rhombus (plural rhombi or rhombuses) is a quadrilateral whose four sides all have the same length. Another name is equilateral quadrilateral, since equilateral means that all of its sides are equal in length. Th ...

-shaped or widely ovate. The sides of the leaves are often heavily grooved and the tips are pointy. In young specimens, both sides of the leaves have hairs. The stems of the leaflets are long. Additional adjacent leaves are present and are about long. The flower heads take the form of axially arrayed

panicle A panicle is a much-branched inflorescence. (softcover ). Some authors distinguish it from a compound spike inflorescence, by requiring that the flowers (and fruit In botany, a fruit is the seed-bearing structure in flowering plants that is ...

s. They are long and have two or three, or many flowers, which can be white, lavender, or purple. The accompanying leaves are about long; the flower stand axes are from . The bell is long and silky. The

sepal A sepal () is a part of the flower of angiosperms (flowering plants). Usually green, sepals typically function as protection for the flower in bud, and often as support for the petals when in bloom., p. 106 The term ''sepalum'' was coined ...

s are longer or of the same length as the shuttles. The crown is purplish or white. The flag is long. The wings are long. In the fruit-ripening stage, a long, wide, unwinged, leguminous fruit develops. There is a ridge along its length and the husk is covered in loose, orange hairs that cause a severe itch if they contact skin. The pods carry up to seven seeds, which are shiny black or brown drift seeds. They are flattened uniform ellipsoids, long, wide and thick. The '' hilum'', the base of the '' funiculus'' (connection between placenta and plant seeds) is a surrounded by a significant '' arillus'' (fleshy seed shell). The dry weight of the seeds is /100 seeds.

Chemistry

The seeds of the plant contain about 3.1–6.1% , with trace amounts of serotonin, nicotine, and bufotenine. ''M. pruriens'' var. ''pruriens'' has the highest content of . An average of 52.11% degradation of into damaging quinones and reactive oxygen species was found in seeds of ''M. pruriens'' varieties.

Taxonomy

Subspecies

*''Mucuna pruriens'' ssp. ''deeringiana'' (Bort) Hanelt *''Mucuna pruriens'' ssp. ''pruriens''

Varieties

* ''Mucuna pruriens'' var. ''hirsuta'' (Wight & Arn.) Wilmot-Dear * ''Mucuna pruriens'' var. ''pruriens'' (L.) DC.Picapica
/ref> * ''Mucuna pruriens'' var. ''sericophylla'' * ''Mucuna pruriens'' var. ''utilis'' (Wall. ex Wight) L.H.Bailey is the non-stinging variety grown in Honduras.

Itch-inducing properties

The hairs lining the seed pods contain serotonin and the protein mucunain, which cause severe itching when the pods are touched. The calyx below the flowers is also a source of itchy spicules and the stinging hairs on the outside of the seed pods are used in some brands of itching powder.G. V. Joglekar, M. B. Bhide J. H. Balwani. An experimental method for screening antipruritic agents. ''British Journal of Dermatology''. Volume 75 Issue 3 Page 117 - March 1963 Scratching the exposed area can spread the itching to other areas touched, which can cause blindness if in the area of the eyes. Once this happens, the subject tends to scratch vigorously and uncontrollably and for this reason the local populace in northern

Mozambique Mozambique (), officially the Republic of Mozambique ( pt, Moçambique or , ; ny, Mozambiki; sw, Msumbiji; ts, Muzambhiki), is a country located in southeastern Africa bordered by the Indian Ocean to the east, Tanzania to the north, Mala ...

refer to the beans as "mad beans" (''feijões malucos''). The seed pods are known as "Devil Beans" in

Nigeria Nigeria ( ), , ig, Naìjíríyà, yo, Nàìjíríà, pcm, Naijá , ff, Naajeeriya, kcg, Naijeriya officially the Federal Republic of Nigeria, is a country in West Africa. It is situated between the Sahel to the north and the Gulf of G ...

Uses

In many parts of the world, ''M. pruriens'' is used as an important

forage Forage is a plant material (mainly plant leaves and stems) eaten by grazing livestock. Historically, the term ''forage'' has meant only plants eaten by the animals directly as pasture, crop residue, or immature cereal crops, but it is also us ...

fallow Fallow is a farming technique in which arable land is left without sowing for one or more vegetative cycles. The goal of fallowing is to allow the land to recover and store Organic compound, organic matter while retaining moisture and disrupting ...

and green manure crop. Since the plant is a legume, it fixes nitrogen and fertilizes soil. In

Indonesia Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania between the Indian and Pacific oceans. It consists of over 17,000 islands, including Sumatra, Java, Sulawesi, and parts of Borneo and New Guine ...

, particularly

Java Java (; id, Jawa, ; jv, ꦗꦮ; su, ) is one of the Greater Sunda Islands in Indonesia. It is bordered by the Indian Ocean to the south and the Java Sea to the north. With a population of 151.6 million people, Java is the world's mo ...

, the beans are eaten and widely known as 'Benguk'. The beans can also be fermented to form a food similar to tempeh and known as Benguk tempe or 'tempe Benguk'. ''M. pruriens'' is a widespread fodder plant in the tropics. To that end, the whole plant is fed to animals as silage, dried hay or dried seeds. ''M. pruriens'' silage contains 11–23% crude protein, 35–40% crude fiber, and the dried beans 20–35% crude protein. It also has use in the countries of

Benin Benin ( , ; french: Bénin , ff, Benen), officially the Republic of Benin (french: République du Bénin), and formerly Dahomey, is a country in West Africa. It is bordered by Togo to the west, Nigeria to the east, Burkina Faso to the nort ...

and

Vietnam Vietnam or Viet Nam ( vi, Việt Nam, ), officially the Socialist Republic of Vietnam,., group="n" is a country in Southeast Asia, at the eastern edge of mainland Southeast Asia, with an area of and population of 96 million, making it ...

as a biological control for problematic '' Imperata cylindrica'' grass. ''M. pruriens'' is said to not be invasive outside its cultivated area. However, the plant is invasive within conservation areas of South Florida, where it frequently invades disturbed land and

rockland hammock The South Florida rocklands ecoregion, in the tropical and subtropical moist broadleaf forests biome, occurs in southern Florida and the Florida Keys in the United States, where they would naturally cover an area of . These forests form on lim ...

edge habitats. Cooked fresh shoots or beans can also be eaten. The plant contains relatively high (3–7% dry weight) levels of , which some people are sensitive to; it can cause nausea, vomiting, cramping, arrhythmias, and hypotension. Up to 88% of the can be extracted from ''M. pruriens'' by boiling and soaking for approximately 48 hours. The efficiency of the process can be slightly improved by using approximately 0.25–0.50% sodium bicarbonate.

Traditional medicine

The plant and its extracts have long been used in tribal communities as an antidote for

snakebite A snakebite is an injury caused by the bite of a snake, especially a venomous snake. A common sign of a bite from a venomous snake is the presence of two puncture wounds from the animal's fangs. Sometimes venom injection from the bite may oc ...

. More recently, its effects against bites by '' Naja'' ( cobra), '' Echis'' ( saw-scaled viper), '' Calloselasma'' (

Malayan pit viper :''Common names: Malayan ground pit viper, Malayan pit viper, Malayan ground snake, Malayan moccasin. ''Calloselasma'' is a monotypic genus created for a venomous snake, venomous Crotalinae, pit viper species, ''C. rhodostoma'', which is Endemism ...

), and '' Bungarus'' ( krait) species have been studied. It has been investigated as a treatment for

Parkinson's disease Parkinson's disease (PD), or simply Parkinson's, is a long-term degenerative disorder of the central nervous system that mainly affects the motor system. The symptoms usually emerge slowly, and as the disease worsens, non-motor symptoms becom ...

due to its high content, while the seeds have been recognized for their ability to significantly alleviate neurotoxicity associated with the condition. The seeds have also been used for treating mood disorders, as well as for

sexual dysfunction Sexual dysfunction is difficulty experienced by an individual or partners during any stage of normal sexual activity, including physical pleasure, desire, preference, arousal, or orgasm. The World Health Organization defines sexual dysfunction ...

in Tibb-e-Unani and Ayurvedic medicine. The dried leaves of ''M. pruriens'' are sometimes smoked.

References

External links

''Mucuna pruriens'' (U.S. Forest Service)

''Mucuna pruriens'' protects against snakebite venom

''Mucuna pruriens'' var. ''utilis''
(Photos)
Chemicals in: Mucuna pruriens (L.) DC. (Dr. Duke's Phytochemical and Ethnobotanical Databases)

''Mucuna pruriens'' a Comprehensive Review

* ttps://web.archive.org/web/20110609131117/http://www.uady.mx/~veterina/publicaciones/journal/2002-2-3/Szabo-b.pdf Research Paper Showing Quantitative Phytochemical Analysis
''Mucuna pruriens'' (Kapikacchu, Atmagupta) entry in Caldecott
{{Taxonbar, from=Q953611 pruriens Medicinal plants of Asia Edible legumes Forages Nitrogen-fixing crops Plants described in 1759 Flora of Nepal