Abrus precatorius is a trailing, liana-like plant that belongs to the legume family (Fabaceae). Its Latin synonyms are rosary pea, jequirity bean, jequirity, crab’s eye, precatory bean, John Crow bead, Indian liquorice.
Device of abrus precatorius
The plant has a trailing growth around trees and shrubs. Its branches are thin, vine-like. Its leaves are long, feathery and composed of numerous smaller leaflets that are arranged in pairs in the leaf petula. Leaf pairs range from 5 to 15, and each petal within them can be 2 to 5 cm long.
The flowers are small, white or coloured in different shades of pink and violet. They have an asymmetrical, funnel-like shape and are collected in racemes in the leaf axils.
Abrus precatorius fruit
The fruit is a pod, with an oblong, flat shape and a pointed tip. It is green as it grows, turning dark brown as it ripens.
Now ripe, it opens to reveal 3 to 8 glossy, hard, shiny red seeds with a black dot. Depending on the variety of Abrus precatorius, its seeds may be coloured in other colours – green, white, black, blue, and yellow.
Prevalence of abscess precatorius
The plant is native to India and grows in tropical and subtropical regions of the world where it has been introduced. It has an invasive type of spread and a tendency to weedy growth.
The usable part of abrus precatorius
The seeds of the herb are used.
Chemical composition of Abrus precatorius
The substance of greatest importance in the composition of the species is called abrin. It is contained in the seeds and is twice as potent as castor bean, although abrin can be absorbed much more slowly than castor bean. Ingestion of whole seeds may not be demonstrated by clinical signs of poisoning as they may pass undigested through the gastrointestinal tract because of their hard shell. When ingested crushed or chewed they cause severe poisoning.
Medicinal properties and uses of abrus precatorius
The seeds of abrus precatorius contain one of the most potent toxins known to man – abrin. Their outer shell is hard, therefore ingested whole they cause only mild symptoms of intoxication, after which the organism usually recovers completely. The hard shell of the seeds protects them from digestive processes, which prevents the toxin from being released from inside them. If the seeds are crushed and ingested, serious poisoning ensues, which can lead to death.
In abrin poisoning, the following symptoms are observed: nausea, vomiting, convulsions, liver failure and death, usually after a few days.
A case is known in which a person swallowed crushed seeds of a plant on purpose. Timely medical intervention and aggressive medical and mechanical therapy saved the patient’s life. In such cases, the outcome is fatal.
In Siddha medicine, for centuries, Abrus precatorius has been used for medicinal purposes. The white variety is used to obtain oil which has aphrodisiac qualities. Tea is made from the leaves and used for fever, cough and cold. The Tamils knew about the poisonous nature of the seeds and suggested various ways to purify them of toxins. One was by boiling the seeds in milk and then drying them. The protein is denatured when subjected to high temperatures, which removes its toxicity.
The plant is also used in Ayurveda and is said to promote hair growth. It is sometimes used as an ingredient in Indian hair products.
The roots of the herb in its native range of distribution are used to relieve discomfort in the abdominal area.
Use of abrus precatorius seeds for making jewellery – brooches, necklaces and bracelets, percussion instruments:
Often the unique seeds of the plant are used to make jewellery. Being shiny and attractive enough, they attract the attention of children and can be ingested by them, with poisoning occurring.
There have been reports that workers who pierce the seeds to get them ready for stringing can suffer poisoning and even death from being pricked with the object they are handling.
In Trinidad in the West Indies, brightly coloured seeds are worn as bracelets around the wrist or ankle to ward off evil spirits and tutors. Tamils use seeds of different varieties of abrus precatorius, the most popular being the red, black, white and green ones.
In March 2012, an order was issued in the United Kingdom to recall all bracelets made from the seeds of the herb, due to their poisonous nature and the evebtual creation of dangerous situations with them.
Seeds of the herb have also been used to make percussion instruments.
Interesting about abrus precatorius
In Rajasthan, India, a song related to this plant has been composed. There is also evidence that it has considerable economic value to the Zulu tribe, due to the fact that it is a form of income for the unemployed Zulu who make and sell various things from its seeds.
The plant has been widely used in Florida as an ornamental such for many years.
This plant is also poisonous to horses.
Laboratory studies on extracts of Abrus precatorius
A variety of pharmacological effects of extracts of the plant have been observed in rodents but have not been demonstrated clinically in humans, including.
Ethyl extract of the plant acts as an antioxidant, anti-inflammatory and analgesic agent in rodents;
methanolic extract of the seeds caused reversible changes in the estrogen cycle and completely blocked ovulation in rats;
methanolic extract, depending on its dose of administration, possesses bronchodilator activity in a guinea pig model.
Studies of aqueous, methanolic and chloroform extracts of Abrus precatorius showed greater inhibitory activity against a range of disease-causing bacteria such as Bacillus subtilis, Pseudomonas aeruginosa, Staphylococcus aureus, Salmonella typhimurium and Escherichia colia.
