259. Copaiba.—Balsam Copaiba.
BOTANICAL CHARACTERISTICS.—Lofty forest trees, natives of Central America, bearing alternate, pinnate leaves. The wood of the trees is replete with oleoresin, sometimes even to bursting.
SOURCE AND COLLECTION.—This oleoresin is derived from several species of copaiba, as C. officinalis (Carthagena), C. langsdorffii (Sao Paulo), C. multijuga (Para). These furnish the several commercial varieties. Obtained by making large augur holes, square or wedge-shaped boxes, into the center of the trunk, where the oleoresin collects. Sometimes these openings are closed or sealed with wax, and of ten the pressure from the high liquid column is said to burst the trunk with a very loud report.. A tree may yield from 10 to 12 gallons.
If 4 fluidrams of the above varieties of copaiba be mixed with 1 ½ fluidrams of aqua ammonia and shaken in a test-tube, the mixture will be clear, but milky if more alkali or fixed oil be present. Maracaibo (Colombia copaiba) is thicker, darker, not always clear. It solidifies, however, with magnesia and contains from 20 to 40 per cent. of the volatile oil.
DESCRIPTION OF DRUG.—A more or less viscid, yellow or light brown, transparent liquid, of about the consistence of olive oil; specific gravity, 0.950 to 0.955 at 25°C. (77°F.); it becomes thicker and darker with age, the volatilization and the oxidation of the volatile oil leaving a greater proportion of the soft resin. Odor peculiar, aromatic; taste bitter, acrid, and nauseous.
Para copaiba is a pale, limpid liquid containing from 60 to 90 per cent. of volatile oil. Maranham and Rio Janeiro copaiba are of the consistence of olive oil, and contain a somewhat smaller proportion of volatile oil—40 to 60 per cent. Maracaibo copaiba is dark yellow or brownish, thick, somewhat turbid. It contains from 20 to 40 per cent. of oil of copaiba.
CONSTITUENTS.—Volatile oil, upon which its value mostly depends; a bitter principle, and two resins, copaibic acid, C20H30O2 (soluble in ammonia and absolute alcohol), and a viscid, non-crystalline resin. Para copaiba contains oxycopaivic acid, C2H28O3; Maracaibo copaiba, metacopaivic acid, C22H34O4. Copaiba contains no benzoic nor cinnamic acids, hence the term balsam is a misnomer.
Preparation of Copaibic Acid.—Mix nine parts of copaiba and two parts of ammonia (sp. gr. 0.95); lower the temperature to 10°C.; crystals of copaibic acid are then obtained, which agree with abietic acid in composition, but not in properties.
ACTION AND USES.—Stimulant, diuretic, laxative. Its principal action, however, is on mucous membranes. Dose: 15 drops (1 mil), in emulsion.
259a. OLEUM COPAIBAE.—OIL OF COPAIBA. A volatile oil distilled from copaiba. A pale yellowish liquid of an aromatic, bitterish taste, and having the general properties of the oleoresin. It is a pure hydrocarbon having the formula C20H32. Dose: 5 to 15 drops (0.3 to 1 mil), in emulsion.