Family: Euphorbiaceae
Scientific name: Ricinus communis
Authority: L.
Common names: umhlakuva (Zulu), castor bean (English)
Trade name: Castor oil
Plant description
Ricinus communis is a fast-growing deciduous small tree (or shrub) that grows up to 6 m in height. It has glossy green or reddish palmate leaves with five-to-twelve deep lobes, unisex flowers with no petals, and fruits in a form of three-celled spiny capsules that contain seeds that are large, shiny, oval in shape, and mottled brown in colour.
Plant properties
The plant contains antioxidant, antinociceptive, anti-asthmatic, anti-fertility, antihistamine, antiulcer, anticancer, antidiabetic, antiprotozoal, anti-inflammatory, antimicrobial, wound healing, and insecticidal activities. Castor seeds are rich in triglycerides, such as ricinolein. As a consequence, castor oil is one of the few naturally occurring glycerides. The seeds contain small amounts of a water-soluble toxin called ricin, that is potentially deadly in concentrated or excess amounts.
Plant uses
R. communis is a versatile plant. The different parts of the tree are useful.
The leaves
- In the 1941-1953 literature review, the leaves extracts are marketed under the trade name Spra Kast, as an insecticide from plants.
- The leaves are galactagogue. They are used to make poultice that women apply on the breast to increase the secretion of milk.
- The leaves are used as poultice or fomentation on sores, boils, and swellings.
- The powdered leaves are used to repel white flies, mosquitoes, aphids, and rust mites.
- The leaves are coated with oil and warmed and applied over the abdomen to give relief in the flatulence in the children.
- The leaves are added to hot water and the infusion used to treat stomach-ache.
- The powdered leaves are used to treat dental caries.
- The powdered leaves are used to treat dracunculiasis.
- The leaves are added to hot water and the mixture used as an emetic in the poisoning by narcotics like opium.
- The decoction made from leaves is used to treat jaundice.
- Fresh leaves are pounded and infused with water to treat baby sicknesses experienced during teething.
The roots
- The roots are boiled in water and the decoction is used to treat lumbago.
- The roots are made into a paste to treat toothache.
- The roots are a strong purgative.
The stem
- The stem is used to make straw boards.
- The stem is dried and used in thatching.
- The stem is dried and used as highly combustible fuel.
The seeds
The seeds are used to make castor oil. The oil is extracted by pressing on the seeds of a castor plant. After extracting, the oil is cooked to destroy the toxin (ricin poison). The extracted crude oil has a distinct odour and pale straw in colour. The refining process deodorises the oil to make it odourless. Bleaching transforms the colour of the oil to yellowish and colourless. After processing castor oil, it becomes a viscous liquid that is tasteless, odourless, and pale amber to colourless.
The name castor oil presumably comes from its use as a substitute for castoreum, a resinous extract used for its scent. Castoreum is made from the dried perineum of the beaver, Latin for castor.
Castor oil uses
Castor oil has a high nutritive value with wide ranging uses. It is used for medicinal, cosmetics, domestic, and industrial purposes.
Traditional medicine uses
The Egyptian medical papyrus of herbal knowledge, known as Papyrus Ebers, that dates back to circa 1550 BC, records the use of castor oil as a laxative in ancient Egypt. Castor is also believed to induce labour during a pregnancy. It can be used alone or mixed with quinine sulphate. The following lists other uses of castor oil in traditional medicine:
- It is used as a mild purgative medicine against almost all ailments in children and the elderly.
- It is used to treat tapeworms and roundworms.
- It is used as a germicide.
- It is used as a disinfectant.
- It is used to treat constipation and indigestion.
- It is used to treat cough, cold, and fever.
Cosmetics uses
Castor oil is used to manufacture the following cosmetics products:
- It is used to make soaps.
- It is used to make ointments skin moisturisers in the form of a lip balm, and face or hand cream.
- It is used to make hair products such as hair conditioners.
- It is used to make perfumes.
Food uses
Castor oil is used in the food industry:
- It is used to preserve food, certain food is coated with the oil to extend shelf life.
- It is used as a food additive and for food colouring.
Industrial uses
Castor oil has numerous industrial uses:
- It is used as a fertiliser, fungicide, and insecticide.
- It is used to make paints, ink for the printer’s ink, and textile dyes.
- It is used to make hydraulic fluid, brake fluid, and aeroplane engine lubricant.
- It is used to make cold resistant plastics.
- It is used as lubricant and lamp fuel.
- It is used to make embalming fluid.
- It is used to make coatings, polishes, adhesives and waxes.
- It is used to make detergents.
Learn about other oils made from plants by accessing: Blue Lotus Oil & Camphor block
Safety precaution:
The use of traditional medicine in prescribed dosages will yield good results. Misuse and abuse may lead to complications. To learn about correct dosage, consult a traditional healer or a herbalist. You can also visit imithiyesintu.co.za or email: info@imithiyesintu.co.za to learn more about traditional medicine.