Kingdom Plantae – Plants
Subkingdom Tracheobionta – Vascular plants
Superdivision Spermatophyta – Seed plants
Division Magnoliophyta – Flowering plants
Class Magnoliopsida – Dicotyledons
Subclass Asteridae
Order Gentianales
Family Asclepiadaceae – Milkweed family
Genus Calotropis R. Br. – calotropis P
Species Calotropis gigantea (L.) W.T. Aiton – giant milkweed
Nepali name: Barahmaase aank, Madaar
English name: Madaar, Swallow-wort
Distribution: Bhutan, India, east to W and C China, Malaysia
They are poisonous plants; calotropin, a compound in the latex, is more toxic than strychnine. Calotropin is similar in structure to two cardiac glycosides which are responsible for the cytotoxicity of Apocynum cannabinum. Extracts from the flowers of Calotropis procera have shown strong cytotoxic activity in the patients of colorectal cancer. They are harmful to the eyes.
Calotropis is a medicinal herb of the Dogbane Family or Apocynaceae. It has two species : Calotropis procera and Calotropis gigantea. C.gigantea is found in Asian Countries mostly whereas C.procera is found on African countries.
Uses:
Food: The bark and latex are used in brewing and to curdle milk.
Fodder: Young pods, senescing leaves and flowers are eaten by goats, occasionally by sheep in times of need, and rarely by cattle and other livestock because they are slightly toxic. Nutritional analysis of shade-dried leaves of C. procera shows they contain 94% dry matter, 43% acid detergent fibre, 20% ash, 19% crude protein, 19% neutral detergent fibre, 5% magnesium, 2% oil, 0.59% phosphorus, 0.2% zinc, 0.04% iron and 0.02% calcium.
Fuel: Stems produce a good charcoal, while the stem pith makes good tinder. Produces an effective and sustained smoky fire, suitable for drying fish. Charcoal has been used for gunpowder in India.
Fibre: White, silky, strong, cylindrical, flexible and durable stem fibre used for various purposes, such as for making ropes, to form cheap cots, gunny bags, bow strings, fishing nets, and in the manufacture of paper, pulp and duplicating stencils. The floss from the seeds, which is about 2-3.5 cm long, white silky and strong, is used as an inferior stuffing for mattresses and pillows as well as for weaving into a strong cloth. The floss may also substitute cotton wool for surgical purposes. Strong inner bark fibres produce a binding material and are processed into fabrics.
Timber: Stems are termite proof and used for roofing and building huts. The very light wood can also be used for fishing net floats.
Latex or rubber: The liquid latex of C. procera can be used as a renewable source of hydrocarbons and intermediate energy resources. Latex contains 11-23% of rubber.
Tannin or dyestuff: A macerated bark extract can be used for dehairing hides and tanning. Additional minor uses includes dyes.
Poison: The bark and the latex are widely used as arrow and spear poisons. The latex is cardiotoxic with the active ingredient being calotropin. Latex of C. procera is 80% effective in inhibiting the activity of the tobacco mosaic virus. The leafy branches are said to deter ants.
Medicine: Compounds derived from the plant have been found to have emeto-cathartic and digitalic properties. The principal active medicinals are asclepin and mudarin. Other compounds have been found to have bactericidal and vermicidal properties. The latex contains a proteolytic enzyme called caloptropaine. An infusion of bark powder is used in the treatment and cure of leprosy and elephantiasis. It is inadvisable to use bark that has been kept for more than a year. The root bark is an emetic, the flower a digestive, and a tonic is used for asthma and catarrh. Bark and wood stimulate lactation in cattle. Roots (extremely poisonous) are applied for snakebite. The milky sap is used as a rubefacient and is also strongly purgative and caustic. The latex is used for treating ringworm, guinea worm blisters, scorpion stings, venereal sores and ophthalmic disorders; also used as a laxative. Its use in India in the treatment of skin diseases has caused severe bullous dermatitis leading sometimes to hypertrophic scars. The local effect of the latex on the conjunctiva is congestion, epiphora and local anaesthesia. The twigs are applied for the preparation of diuretics, stomach tonic and anti-diarrhoetics and for asthma. Also used in abortion, as an anthelmintic, for colic, cough, whooping cough, dysentery, headache, lice treatment, jaundice, sore gums and mouth, toothache, sterility, swellings and ulcers.
