Cucumis colocynthis. Colocynth.
Nat. Ord. — Cucurbitaceae. Sex. Syst. — Monoecia Monadelphia.
The Fruit Deprived of its Rind.
Description. — Colocynth, or Bitter Cucumber, is an annual plant, bearing some resemblance to that of the watermelon, with a whitish root, and herbaceous, trailing, angular, branched, rough and hispid stem. The leaves are alternately on long petioles, of a triangular form, deeply and obtusely sinuated, of a bright green on the upper surface, paler beneath with whitish hairs; tendrils short; the flowers are solitary, axillary, pedunculate, and of a yellow color. The calyx of the male flower is bell-shaped; the corolla is monopetalous, campanulate, divided at the margin into five pointed segments. The stamens are three, short, distinct; two are bifid at the apex, or rather have two anthers. The female flower is like the male, but the filaments are destitute of anthers. The ovary is inferior, large, with a very short cylindrical style, furnished with three thick stigmas. The fruit is a round pepo, the size and color of an orange, and smooth on the outside when ripe ; the rind is thin, hard, and coriaceous ; internally it is trilocular, each cell containing numerous ovate-acute, compressed seeds, enveloped by a white spongy pulp.
History. — The Bitter Apple, or Cucumber is a native of Northern Africa, the Cape of Good Hope, Western Asia, etc., and is cultivated in Italy and Spain. The fruit is collected in autumn when it begins to turn yellow, and after having been peeled, is dried quickly either in a stove, or by the sun. The colocynth with which the United States is supplied, is chiefly derived from the ports of the Levant. That which is deprived of its rind, is very white, light, spongy, and without seeds, is considered the best article ; that which contains the seeds is inferior ; and the grayish or brownish pith of the larger fruits is of the poorest quality. The pulp only of the fruit is the officinal portion ; the fruit, as usually met with in the shops, is about the size of a small orange. The pulp is tough, pulverized with difficulty, nearly inodorous, but intensely and disagreeably bitter. Water, ether, or alcohol acquires its active properties; water forms a mucilaginous solution, from which the extract of colocynth is obtained by evaporation ; it is pale-brown, translucent, elastic, and intensely bitter. Analysis has detected in colocynth, a bitter principle called Colocynthin, extractive, fixed oil, resin insoluble in ether, gum, pectic acid, phosphates of lime and magnesia, lignin, and a little water. It is incompatible with the fixed alkalies, sulphate of iron, nitrate of silver, acetate of lead, and vegetable astringents, containing tannin or gallic acid.
Colocynthin may be obtained by exhausting the pulp previously freed from the seeds, with successive portions of cold distilled water, until it is deprived of its bitterness ; then filtering the solution, heating it to boiling point, and adding, while hot, diacetate of lead, as long as any precipitation continues. When cold, filter the supernatant liquid, and gradually add to it diluted sulphuric acid, until it no longer throws down a precipitate ; again boil to remove the free acetic acid, and filter to separate the sulphate of lead. By this means all the organic matter, except the colocynthin, is removed. Evaporate the filtered liquor cautiously and nearly to dryness, and. dissolve the colocynthin out of the residuum by means of strong alcohol, which leaves the salts undissolved as sulphates. By evaporating the alcoholic solution the colocynthin is obtained pure. Colocynthin is an amorphous, yellowish-brown, somewhat translucent, brittle, and friable substance, fusible at a temperature below 212°, inflammable, more soluble in alcohol than in water, but imparting to the latter an intense bitterness. It is neutral ; with infusion of galls its aqueous solution gives a copious white precipitate.
Properties and Uses. — Colocynth is a powerful drastic, hydragogue cathartic, exciting inflammation of the mucous membrane of the intestines, causing severe griping, vomiting, and bloody discharges. In small doses it acts powerfully and harshly, and is, therefore, never used alone, but generally in combination with other cathartics, which tends to modify its irritating influence. The addition of extract of hyoscyamus will likewise deprive it of its harsh and griping effects. Its principal employment is in passive dropsy, in cerebral derangements, and in pills with other cathartics for the purpose of overcoming torpid conditions of the biliary and digestive systems. Its irritant effect upon the rectum may influence the uterus by sympathy of contiguity, and thus provoke menstruation, and on the same principle, dissolved in whisky, it has cured gonorrhea. It may be used in moderate doses, in all diseases where catharsis is indicated. The powder applied to an ulcer, or raw-surface, affects the lower bowels in the same manner as when taken internally. It is said that Hippocrates used the colocynth as a pessary for the purpose of exciting menstruation. The oil of colocynth has been recommended as an external remedy for neuralgia. Dose of colocynth, is from four to ten grains, either in powder, or aqueous extract; of the alcoholic extract, from one to four grains. When to be given alone, it should be triturated with some inert or insoluble powders, as gum or farinaceous matter, in order to diminish its severity of action.
Off. Prep. — Extractum Colocynthidis; Extraction Colocynthidis Compositum.