castor oil

It is widely distributed in the bulk of tropical and subtropical countries wildly or semi-culturally. Homeland, probably Ethiopia. The centers of culture are India, Brazil, Argentina, Africa, China, Iran, the USSR. It has been bred in Egypt for over 4000 years.

At home – a perennial plant with a tree-like stem up to 10 m tall. Under conditions of cultivation in countries with a temperate climate (USSR, etc.) – an annual plant up to 2-3 m tall. The stem is articulated-branched, along with the branches green or painted in pink, red, purple and almost black. The leaves are alternate, with petioles 20-60 cm long; plate glabrous, thyroid, 30-80 cm long, 5-11-digitipartite; leaf lobes oblong, toothed. Inflorescences are racemes, terminal and in leaf axils. Flowers unisexual, monoecious; groups of staminate flowers – in the lower part, pistillate flowers – in the upper part of the inflorescence axis. Stamens numerous, in branched bunches; pistils with a tripartite column and fringed stigmas of red, crimson or light yellow. The fruit is a spherical capsule, naked or with thorns, three-seeded, tricuspid, cracking or non-cracking. Type prefabricated, many races and varieties; there is a lot of selection work going on.

Mature seeds (Semen Ricini) are oval in shape, convex on the dorsal side, flatter on the ventral side, with a longitudinal seam in the middle. The shell is smooth, shiny, variegated, mosaic. Depending on the castor bean variety, the color of the mosaic is brown, pink, light pink-contrasting against the background of the seed, from gray to copper-red. The shape and variegated color of the seed resemble a tick. At the top of the seed is a seedling, which looks like a white appendage, easily falling off.

Castor seeds contain fatty oil, depending on the variety from 40 to 60%. The seed nucleus is rich in proteins (up to 17%), including toxalbumin ricin (2-3%) – a very poisonous substance. Poisonous and alkaloid ricinin (0.1-1%), belonging to the group of pyridine alkaloids with a cyano group among the substituents.

Medical castor oil is the fraction obtained during the first hot pressing. To destroy the ricin, the oil is treated with hot steam; ricin is an unstable substance and is destroyed as a result of hydrolysis.


Medical castor oil (Oleum Ricini) pale yellow, characteristic odor, thick, viscous. It contains up to 85% triglyceride ricinoleic acid, which is a monooxy-oleic acid (hydroxy group is at C 2 ).


The rest of the number of triglycerides falls on oleic (9%), linoleic (3%) and saturated acids (up to 3%). Due to ricinoleic acid, castor oil, unlike all other fats, is soluble in 95% alcohol (starting with an equal volume).

Castor oil is a classic laxative. It is part of some liniments (for example, balsamic, which have antiseptic properties and the ability to accelerate tissue regeneration).

Technical (including special) grades of castor oil are widely used in various industries. Its high viscosity at high temperatures and non-oxidation properties make castor oil an exceptionally valuable lubricant for electric motors.

The plant contains liquid fats (oils).


Fats consist almost entirely of triglycerides of high molecular weight fatty acids. They are accompanied by pigments, sterols, vitamins and some other fat-soluble substances.

The fatty acids that make up triglycerides can be saturated or unsaturated. Most often, triglycerides contain the fatty acids listed in the table.

Fats are not individual substances – they are mixtures of triglycerides. In the formation of fats, the law of maximum heterogeneity prevails – more than 1300 currently known fats are formed by “multi-acid” triglycerides, and fatty acids of different composition (for example, stearinodiolein, palmitinooleinolinolein, etc.). Fats, consisting of “one-acid” triglycerides, are relatively rare in nature (olive oil is triolein, castor oil is triricinolein).

The properties of fats are determined mainly by the composition of fatty acids and their quantitative ratio. Saturated fatty acids form triglycerides of a dense consistency (at traditional temperature), and the density increases with the increase in the number of carbon atoms in the acid (see table). Unsaturated fatty acids form liquid triglycerides.


Liquid fats (oils), spread with a thin layer, can remain liquid (non-drying fatty oils) or, oxidized, gradually turn into a resinous film (drying – a dense film and semi-drying – a soft film). Fatty oils dominated by oleic acid triglycerides are non-drying. The more linoleic and linolenic acids in oils, the more they are prone to drying out, as can be judged by the iodine number (the number of grams of iodine that can join 100 g of fat at the place of double bonds of unsaturated acids). Approximate limits of iodine numbers: non-drying 80-100, semi-drying 100-140, drying oils 140-200.

Most vegetable fatty oils are obtained by pressing or extracting raw materials with volatile solvents. Freshly obtained (“raw”) fats are purified (refined).

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