Cocculus palmatus. Colombo.
Nat. Ord. — Menispermaceae. Sex. Syst, — Dioecia Hexandria.
Description. — Colombo is a climbing plant, with a perennial root, formed of a number of fasciculated, fusiform, somewhat branched, fleshy, curved, and descending tubers, of the thickness of an infant's arm, covered with a thin, brown epidermis, marked, especially toward the upper part, with transverse warts ; internally they are deep yellow, inodorous, very bitter, and filled with numerous, parallel, longitudinal fibers or vessels. The stems, of which one or two proceed from the same root, are annual, herbaceous, about as thick as the little finger, simple in the male plant, twining, branched in the female,rounded, green ; in the full-grown plant, below, thickly clothed with succulent, longitudinal hairs, which are tipped with a gland. The leaves are alternate, large, the younger ones thin, pellucid, bright-green, generally three-lobed, upward gradually more numerous ; older ones remote, a span in breadth, nearly orbicular, deeply cordate, five to seven-lobed, the lobes entire, often deflexed, wavy on the surface and margin, dark-green above, paler beneath ; hairy on both sides ; the nerves according to the number of lobes, are three, seven, or nine, pale, connected by veins which, in themselves, are reticulated, prominent beneath. Petioles about as long as the leaves, rounded, glanduloso-pilose, thickened below. The flowers are small and inconspicuous, and are arranged in the male plant in solitary, axillary, drooping, compound racemes, covered with glandular hairs, and with small caducous bracts at the base ; in the female also axillary, solitary, simple, spreading, shorter than those of the male. The calyx is glabrous, of six sepals, arranged in a double series. The corolla consists of six pale-green petals in a single row; The stamens are six, with terminal, truncate, four-celled anthers. The pistils are three, of which two are often abortive ; stigma spreading. The fruit is drupaceous or berried, about the size of a hazelnut, densely clothed with long spreading hairs, tipped with a black, oblong gland. The seeds are somewhat reniform, of a black color, and transversely striate.
History. — This plant inhabits the forests near the coast of Mozambique, and Oibo in East Africa, and has been cultivated at Madras, and in the Isle of France. It was formerly incorrectly described as Menispermum Palmatum, and has only recently been properly investigated and classified. It grows abundantly on the south-eastern coast of Africa, in the neighborhood of Mozambique, where it is known by the name of Kalumb. The root is dug up in the dry season in the month of March, and only the fusiform offsets are taken, as the main root is too fibrous and woody ; these are transversely sliced, strung on cords, and dried in the shade. As met with in the shops, the roots consist of transverse sections, from half an inch to three inches in diameter, and from one-eighth of an inch to one inch in thickness. These sections are flat, circular, or oval, and composed of a thin, outer epidermis, brown and wrinkled,
— a thick, bright-yellow inner bark, of a slightly-greenish color internally,
— and a light, spongy, yellowish, ligneous internal or medullary portion, usually more or less shrunk, so that the center of the sections are the thinnest, and frequently marked with concentric circles and radiating lines. Those pieces are the finest which are the most compact and uniform in their texture, least worm-eaten, and have the brightest color. The root is brittle and easily pulverized, the powder having a pale greenish-yellow tint, becoming darker by age, a faint aromatic odor, a strong bitter taste, without acrimony or astringency. The cortical portion of the root possesses the greatest intensity of bitterness. It readily imparts its bitterness to water, alcohol, or ether. The powder undergoes decomposition by attracting moisture from the air, and should, in consequence, be prepared in small quantities at a time, and kept in well-corked bottles. Colombo contains an azotized substance, in large quantity, a bitter yellow substance not precipitated by metallic salts, one-third its weight of starch, a small proportion of volatile oil, salts of lime and potassa, oxide of iron, and silica, beside colombin and berberin. It may be known from American Colombo, by an infusion of the latter becoming darkgreen with the sesquichloride of iron, and not being affected by the tincture of galls ; while the imported is not affected by the iron, and yields a copious grayish precipitate with galls.
Colombin may be obtained by exhausting Colombo by means of alcohol of sp. gr. 0.835, distilling off three-fourths of the alcohol, allowing the residue to stand for some days till crystals are deposited, and lastly, treating these crystals with alcohol and animal charcoal. The mother waters still contain a considerable quantity of colombin, which may be separated by evaporating with coarsely-powdered glass to dryness, exhausting the residue with ether, filtering, distilling off the ether, treating the residue with boiling acetic acid, and evaporating the solution so that crystals may form. The crystals are in beautiful transparent quadrilateral prisms, inodorous, and extremely bitter. They are soluble in boiling alcohol, which deposits them on cooling, and but slightly soluble in water, alcohol, or ether, at 60°, although the bitter taste is imparted to these fluids. Diluted acetic acid is the best solvent. Alkaline solutions take up colombin, and from which acids precipitate it. It has neither acid nor alkaline reactions.
Berberin exists more largely in the Colombo root, than Colombin, it exists in combination with Colombic Acid forming a Colombate of Berberin, which exists in the thick layers of the cell membranes, while colombin occurs in the cells of the root in a crystalline state. It may be obtained by exhausting Colombo with alcohol of 0.889, distilling off the alcohol, allowing the residual liquor to stand for three days so as to deposit its colombin, then evaporating the supernatant liquid, together with the aqueous washings of the colombin, to dryness, exhausting the residue with boiling alcohol of 0.863, treating the solution thus obtained as the former one, submitting the residue to the action of boiling water, filtering and adding muriatic acid, collecting the precipitated muriate of berberin thus formed, on a filter, drying it with bibulous paper, and finally, to separate adhering acid, dissolving it in alcohol, and precipitating with ether. The precipitate will be a bright yellow powder, imperfectly crystalline, and disagreeably bitter.
Precipitates of the solutions of Colombo are caused by infusion of galls, acetate of lead, corrosive sublimate, and lime-water, but which do not affect its bitter principle.
Properties and Uses. — A pure, bitter tonic. Used in dyspepsia, chronic diarrhea, and dysentery ; in convalescence from febrile and inflammatory diseases, hectic fever, and in the muscular debility of young children. It has been recommended in sympathetic vomiting, not connected with inflammation of the stomach, as in that of pregnant women. Like other strong bitters, it occasionally checks the remittent and intermittent fevers of hot climates. A powerful tonic may be formed of the alcoholic extract of the root. In dyspepsia, and vomiting it may be advantageously combined with the alkaline bicarbonates, as well as in debility with acidity of the stomach. It is used in various combinations, with aromatics, antacids, cathartics, or other tonics. Dose of the powder, from ten to thirty grains, three or four times a day ; of the infusion, from one to two fluidounces ; of the tincture, from one to two fluidrachms.
Off. Prep. — Infusum Colombae ; Tinctura Colombae ; Vinum Symphyti Compositum.