Related entry: Manihot.—Tapioca
The seeds of Curcas purgans, Adanson (Jatropha Curcas, Linné).
COMMON NAMES: Purging-nut, Physic-nut, Barbadoes-nut.
Botanical Source.—A large shrub, with a milky juice, and leaves that are heart-shaped, smooth, 5-lobed, and borne on leaf-stalks 2 or 3 inches long. The flowers are small, green, monoecious and in axillary, stalked cymes. The corolla and calyx are 5-parted, and the male flowers have 10 stamens. The ovary is 3-lobed, 3-celled, and has a 3-parted style. The fruit is a fleshy black berry, and contains 3 seeds, about an inch in length. The kernel is oily, inodorous, sweetish to the taste, followed by acridity.
History.—This is a large, thick-stemmed, lactiferous shrub, a native of the Cape de Verd Islands (Pickering), but cultivated as a hedge plant, as well as for its oil, and has also been naturalized in the West Indies, South America, and in most parts of the tropics. The plant was formerly referred to Jatropha, from which it differs in having a monopetalous corolla. The seeds are called Purging-nuts, Nuces catharticae Americanae, Semina ricini majoris, Semen curcadis, Ficus infernalis, Nuces Barbadenses, Physic-nut, etc., (New Remedies, 1878, from Zeitschrift des Oesterr. Apoth. Vereins), and affords an oil, upon pressure, which is a drastic cathartic, and which has been used to adulterate croton oil.
Description.—The seeds are about 1 inch long, oval, flattish on one surface, rounded on the opposite, each side presenting a slight elevation, running lengthwise. It has a fissured testa of a blackish color. Taste at first sweet, afterward acrid. It has no odor and contains oil.
Chemical Composition.—The oil was examined by M. J. Bouis (1854) (Comptes Rendus, Vol. XXXIX) who obtained it from the nuts, by pressure, to the amount of 37 per cent. It is white, has a density of 0.910 at 16.5° C. (62° F.), is almost insoluble in alcohol, easily saponified by soda, forming a white, hard soap. It is decomposed by heat, yielding, among other products, sebacic acid. When saponified by potash, if the resulting soap is decomposed by hydrochloric acid, a mixture of fatty acids is produced, from which, by pressure, from 18 to 20 per cent of a white, solid acid may be separated. This is soluble in hot alcohol, from which, on cooling, it is deposited in brilliant spangles. From its close resemblance to cetic acid (from spermaceti), Bouis named it isocetic acid. August Siegel, of Dorpat, who more recently (1893) investigated the seeds of Curcas purgans, found isocetic acid to be a mixture of palmitic and myristic acids, and isolated a peculiar fatty acid of the formula C15H28O3, which he called curcinoleic acid. Besides, he obtained from the seeds, previously deprived of their fatty oil, a toxic albuminoid substance, soluble in water and resembling the poisonous principle of Amanita phalloides. It was named curcin, and becomes inert when exposed to temperatures above 50° C. (122° F.), or when treated with precipitants. The percentage composition of the seeds was found by Siegel as follows: Water, 7.2; ash, 10.2; oil, 33.86; sugar, coloring matter, cellulose, 47.83; albuminoids, 1.71 (Amer. Jour. Pharm., 1893).
Action, Medical Uses, and Dosage.—The seeds of Purging or Barbadoes-nut occasion emetic and drastic cathartic effects, accompanied with a burning sensation in the fauces and stomach, and other unpleasant, and even serious, symptoms. However, if the seeds be entirely deprived of their embryo, the emesis and other disagreeable sensations do not occur. The juice of the leaves acts as a rubefacient, and has been successfully employed, in the countries where the shrub grows, as a local application in rheumatic pains, in certain eruptive affections, and in piles. The oil, in the dose of 10 or 12 minims, is a cathartic, somewhat resembling croton oil in its action, though less severe. It may be used in all cases where the employment of croton oil is indicated.
Related Species.—Curcas multifidus, Endlicher (Jatropha multifida, Linné). South America. The seeds resemble somewhat the Barbadoes nut and yield an oil probably identical with that from the seeds of Curcas purgans.
Anda Gomesii, Jussieu (Joannesia principis, Vellozo; Anda basiliensis, Raddi). The Anda-assú tree of Brazil, yielding purgative brown, chestnut-like seeds, having the taste of peach kernels. The seeds act violently as a purgative, and may even act as an emeto-cathartic. The reddish, limpid oil, of which the seeds yield about 50 percent, is also actively cathartic. By preparing the seeds in emulsion, the germ and testa being first removed, a griping constituent is avoided, and the oil may be used in the place of castor oil, the action of which it closely resembles. Doses of ℨii to ℨiii act gently and efficiently. Large doses harshly overact.
Jatropha macrorhiza. Jicama (Euphorbiaceae).—Northern Mexico and Texas. An active purgative in overdoses; a mild evacuant and cholagogue in doses of 1/4 drachm to 2 fluid drachms of the fluid extract.