Copaiba. U. S., Br. Copaiba.
Copaib. [Balsam of Copaiba, Copaiva]
Preparation: Oil of Copaiba
"An oleoresin derived from South American species of Copaiba (Fam. Leguminosae)." U. S. " Copaiba is the oleo-resin obtained by incision from the trunk of various species of Copaifera, Linn." Br.
Balsamum Copaiferarum; Balsam Copaiba, Balsam Capivi; Copahu, Fr. Cod.; Oleoresine (Baume) de Copahu, Fr.; Balsamum Copaivae, P. G.; Copaiva; Copaivabalsam. G.; Balsamo di Copaive, It.; Copaiba, Balsamo de Copaiva, Sp.
Copaiba was first noticed in a work published by Purchas, in England, in 1625. The next reference to it was by Cristoval d'Acuna, in 1638. In 1648, Marcgraf and Piso gave a detailed account of the tree which produces it, and the methods of gathering it. Jacquin in 1763 described a species of Copaifera, growing in Martinique, which he named C. officinalis. As this was believed to be the same plant with the one observed by Marcgraf in Brazil, it was adopted in the Pharmacopoeias, but their identity was denied; and Desfontaines proposed for Jacquin's species the title of C. Jacquini, in honor of that botanist. It is now known that many species of Copaiba (Copaifera) exist in South America, and all of them, according to Martius, yield copaiba. Besides C. officinalis (L.) Jacquin, the following yield Copaiba: C. guianensis (Deaf.) O. Kuntze, C. Langsdorffii (Desf.) O. Kuntze, and C. coriacea (Mart.) O. Kuntze.
The juice is obtained by making a square chamber in the stems of the trees, reaching to the very center; and the operation is said to be repeated several times during the same season. It is asserted that a single tree will yield about forty liters. As it flows from the wound, it is clear, colorless, and very thin, but it soon acquires a thicker consistence, and a yellowish tinge. It is most largely collected in the provinces of Para and Maranham, in Brazil, and is brought to this country from the port of Para, in small casks or barrels. Large quantities of it come from Maracaibo, in Venezuela, and from other ports on the Caribbean Sea, whence it is brought in casks, demijohns, cans, jugs, etc. The drug is also exported from Angostura, Cayenne, Rio Janeiro, and some of the West India islands.
C. officinalis is a native of Venezuela, and grows in the province of Carthagena, mingled with the trees which afford the balsam of Tolu. It grows also in some of the West India islands, particularly Trinidad and Martinique. This is the source of the Maracaibo or Venezuela Copaiba, which is also obtained in part from C. guianensis. This variety of Copaiba is distinguished by being dextrogyrate, more viscid and darker in color.
Numerous varieties of true South American copaiba exist in commerce, known under the name of the various ports of shipment. The most important of these varieties besides Maracaibo is the Para or Maranham Copaibo, which is derived from C. Langsdorffii and C. coriacea, which is characterized by being optically laevo-gyrate. The other varieties are Bahia, Carthagena, Maranham, and Cayenne. Each one of these varieties has been referred (see P. J., 1901, lxvi, 325) to a special species of the genus Copaiba, but there is little reason for supposing that this reference is accurate, and there is much reason for believing that various trees contribute to a single variety of copaiba. The following table, according to the researches of Umney and Bennett, shows the specific gravities and percentage of oil of the five most important of these copaibas:
|Name.||Sp. gr.||Per cent. of oil.||Resin.|
|Maracaibo||0.969||42.5||Firm. but not easily pulverized.|
All of the above varieties answered to the solubility and Gurjun balsam tests.
It will be noticed that the Para and Bahia specimens examined by Umney failed to comply with the tests of the U. S. Pharmacopoeia (1890), and yet, supposing that the oil represents the chief therapeutic principle of copaiba, these varieties lead all the others. The German Pharmacopoeia requires that the specific gravity shall be 0.98 to 0.99, and that the acid number shall fall between 75.6 and 84, and the ester number be not more than 8.4. Dieterich. (P. J., April, 1899, and March, 1900.) Surinam copaiba is a yellowish or brownish-yellow liquid, of varying' consistence; it may be distinguished from Maracaibo copaiba by the fact that one drop of it dissolved in 1 mil of acetic anhydride gives a fine blue color on the addition of a drop of sulphuric acid. (P. J., Nov., 1904.)
According to E. Keto, copaiba of Maracaibo has a density of 0.999; a coefficient of acidity of 85.4; of etherification of 6.7; while that of Para has a density of 0.92; a coefficient of acidity of 19.4; of etherification of 7.4.
Properties.—Copaiba is a clear, transparent liquid, usually of the consistence of olive oil, of a pale yellow color, a peculiar not unpleasant odor, and a bitterish, hot, nauseous taste. Its sp. gr. varies ordinarily from 0.950 to 1.000, but has been known to be as low as 0.916. (Procter, A. J. P., xxii, 292.) It is insoluble in water, but entirely soluble in absolute alcohol, ether, and the fixed and volatile oils. Strong alkaline solutions dissolve it perfectly; but the resulting solution becomes turbid when largely diluted with water. With the alkalies and alkaline earths it forms compounds, in which the resin of the copaiba acts the part of an acid. It dissolves magnesia, especially with the aid of heat, and even disengages carbon dioxide from the magnesium carbonate. If triturated with a sixteenth of its weight of magnesium oxide and a little water and set aside, it gradually assumes a solid consistence, and a similar change is produced with calcium hydroxide. Solid Copaiba or Mass of Copaiba was official in the U. S. P., 1890, and is now official in the National Formulary IV, Part III. See also U. S. Dispensatory, 19th edition, p. 398. The essential constituents of copaiba are volatile oil and resin, with at times small quantities of acids. As it contains no benzoic acid, it cannot properly be called balsam of copaiba. The substances which it most closely resembles, both in composition and in properties, are the turpentines. (See Oleum Copaiba.) For a description of an apparatus for distilling the volatile oil, see a paper by R. A. Cripps in C. D., 1892, 282. Cripps found commercial copaiba to contain the following percentages of volatile oil: 40.95, 45, 45.3, 46.4, 47.8, 48.2, 49.6, 50.4, 50.8, 53.3, 59.6. J. C. Umney (A. J, P., 1893, 544) found in African copaiba 39 per cent. of an oil of 0.918 specific gravity and with a rotation of +20° 42', the last character distinguishing it from the other varieties which yield laevorotatory oils.
The official description of Copaiba is as follows: "A pale yellow to brownish-yellow, more or less viscid liquid, either without fluorescence or with only a slightly greenish fluorescence; having a peculiar, aromatic odor, and a persistent, bitter, and acrid taste. It is insoluble in water and partly soluble in alcohol. Soluble, showing not more than a slight opalescence,
in dehydrated alcohol, carbon disulphide, or in fixed or volatile oils; completely soluble in chloroform or ether and also soluble in an equal volume of petroleum benzin, a further addition of the solvent producing a flocculent precipitate. Specific gravity: 0.940 to 0.995 at 25° C. (77° F.). When heated on a water bath, no odor of oil of turpentine is evolved; and when all of the volatile oil has been driven off, a hard and brittle resin remains, weighing not less than 36 per cent. of the original weight of the Copaiba taken (paraffin or fatty oils). To about 1 G-m. of Copaiba, accurately weighed, add 50 mils of alcohol and 1 mil of phenolphthalein T.S., then titrate the solution with half-normal potassium hydroxide V.S. It shows an acid value of not less than 28 nor more than 95. Dissolve 3 or 4 drops of the volatile oil separated from Copaiba by distillation with steam, in 3 mils of glacial acetic acid, mix the solution with 1 drop of a freshly prepared aqueous solution of sodium nitrite (1 in 10), and carefully underlay this with 2 mils of sulphuric acid. The acetic layer is not colored pink (gurjun balsam). Shake 5 mils of Copaiba with 15 mils of alcohol and then heat the mixture to boiling for one minute; no oil separates after cooling and allowing it to stand for one hour (paraffin oils). The volatile oil separated from Copaiba by distillation with steam does not boil below 250° C. (482° F.), and shows an angle of rotation in a 100 mm. tube of not less than -7° at 25° C. (77° F.). (African Copaiba); U. S.
"A more or less viscous liquid, generally transparent and occasionally fluorescent, yellow to golden brown. Specific gravity 0.975 to 0.995. Entirely soluble in absolute alcohol; soluble in four times its volume of petroleum spirit, the solution yielding only a slight filmy deposit on standing. Aromatic, characteristic odor; taste acrid, somewhat bitter, persistent. Loses about 45 per cent. of its weight when heated for forty-eight hours to 100° C. (212° F.). Forms a transparent solution with one-third of its volume of solution of ammonia. Four drops carefully added to a mixture of 5 millilitres of glacial acetic acid with four drops of nitric acid do not yield a purplish or violet color (absence of gurjun balsam). 1 gramme dissolved in 25 millilitres of absolute alcohol requires for neutralisation not less than 2.7 millilitres of N/2 alcoholic solution of potassium, hydroxide, solution of phenolphthalein being used as indicator (presence of a due proportion of acid resins). The volatile oil distilled from it responds to the tests described under 'Oleum Copaibae.' " Br.
The resinous mass which remains after the distillation of the oil is hard, brittle, translucent, greenish-brown, and nearly destitute of odor and taste. By mixing it with the oil in proper proportion, we may obtain a liquid identical or nearly so with the original juice. This resinous mass is of an acid character, and yields a series of amorphous salts; it may be obtained pure by exposing a mixture of 9 parts of copaiba and 2 parts of aqueous ammonia (sp. gr. 0.95) to a temperature of 10° C. (50° F.). In this way crystals of copaivic acid, C20H30O2, are obtained. This acid agrees with the abietic acid of rosin in composition, but not in properties. Copaivic acid is readily soluble in alcohol, and especially in warmed copaiba itself; much less soluble in ether. When recrystallized from alcohol, copaivic acid fuses at 116° to 117° C. (241°-242.6° F.). (A. J. P., 1879, p. 305.)
An analogous substance, oxycopaivic acid, C20H28O3, was found in 1841 by H. von Fehling in Para copaiba, and Strauss, in 1865, extracted meta-copaivic acid, C22H34O4, from Maracaibo copaiba. Copaivic acid forms crystallizable salts with alkalies, and sodium copaivate, NaC20H29O2, made by combining molecular quantities of the acid and soda, is asserted by Zlamal and Roquette to be more efficient than any other preparation of copaiba. Tschirch (Harze und Harzbehälter, 1900, p. 297) obtained from Maracaibo balsam a crystalline resin acid corresponding in many respects with Strauss's metacopaivic acid, to which, however, he gave the formula C11H16O2, finding a melting point 89° to 90° C. (192.2°-194° F.) as against 205° to 206° C. (401°-402.8° F.) for Strauss's acid. Para balsam was found by Tschirch to contain two crystallizable resin acids together with several uncrystallizable ones. African copaiba balsam he found to contain a characteristic acid to which he gave the name illurinic acid and the formula C14H20O2 or possibly C21H30O3. Keto, who worked out the preceding results jointly with Tschirch, has since published some additional results. (J. P. C., 1902, p. 381.) He finds in Para balsam the two crystallizable acids referred to above, one of which he names para-copaibic acid with the formula C20H32O3 and fusing point 142° to 145° C. (287.6°-293° F.), and the other homoparacopaibic acid, C18H28O3, fusing at 111° to 112° C. (231.8°-233.6° F.). To illurinic acid mentioned by Tschirch he gives the formula C20H28O3 and the melting point 128° C. (262.4° F.).
Copaiba, upon exposure to the air, acquires a deep color, a thicker consistence, and greater density, and, if spread out upon an extended surface, ultimately becomes dry and brittle. This change is owing partly to the volatilization and partly to the oxidation of the essential oil. As it is the soft resin that results from the oxidation of the oil, it follows that the proportion of this resin increases with age. Considerable diversity must, therefore, exist in the drug, and in its physical properties and in the proportions of its ingredients, according to its age and degree of exposure. Similar differences also exist in the copaiba procured from different sources. Thus, that of the West Indies, when compared with the Brazilian, which is the variety above described, and in common use, is of a thicker consistence, of a deeper or darker yellow color, less transparent, and of a less agreeable, more terebinthinate odor. They differ also, as observed by Buignet, in their action on polarized light, in which they differ not only in degree, but sometimes also even in direction. (J. P. C., Oct., 1861, pp. 266-7.) It is not impossible that differences may exist in the drug according to the circumstances of its collection. The species of Copaifera from which the .oleoresin is collected, as well as the age of the tree, its position, and the season of collection, must also have influence over the product. It is highly probable that the resinous matter results from the oxidation of the oil in the cells of the plant, and that the less elaborated the oleoresin may be, the larger proportion it will contain of the oil. It is said that a volatile oil flows abundantly from a tree near Bogota, which is employed to adulterate the copaiba collected in that vicinity and shipped from Maracaibo and other neighboring ports. African Copaiba, or Balsam of Illurine, which reached the London market first in 1891, from West Africa, is a brownish substance, having a consistency similar to the Maracaibo copaiba, and a greenish fluorescence. Its aromatic odor is entirely different from that of copaiba; its taste is biting, with an after-taste of bitterness. According to Keto (J. P. C., 1902, 381), its density is 0.9905; its coefficient of acidity 55.5; of etherification 8.3. It is soluble in chloroform and petroleum benzin, also in ether, with which it makes an opalescent liquid. Its solution in absolute alcohol, or alcohol of 95 per cent. is not limpid. From it Keto separated illurinic acid. Its volatile oil is of a pale yellow color, with a strong odor entirely different from that of copaiba. The residue which remains after the distillation consists of two resins, one soluble, the other insoluble, in alcohol. This oleoresin probably shares the medicinal properties of true copaiba, and is the product of Hardwickia Mannii Oliver, a tree closely allied to the true copaibas. (See Apoth. Zeit., 1894, p. 9.)
Adulterations.—Copaiba is often adulterated with a fixed oil, especially castor oil, which, in consequence of its solubility, cannot, like the others, be detected by alcohol. Various plans have been proposed for recognizing the castor oil. The simplest is to boil a drachm of the copaiba in a pint of water until the liquid is wholly evaporated. If the copaiba contains a fixed oil, the residue will be more or less soft, according to the quantity present; otherwise it will be hard. Magnesium carbonate, potassium hydroxide, and sulphuric acid have also been proposed as tests. In the old Edinburgh Pharmacopoeia it was stated that copaiba "dissolves a fourth part of its weight of magnesium carbonate, with the aid of a gentle heat, and continues translucent." The presence of a small proportion of any fixed oil renders the mixture opaque. One part of potassium hydroxide dissolved in two of water forms a clear solution with nine parts of pure copaiba, and the liquid continues clear when moderately diluted with water or alcohol; but the presence of one-sixth of fixed oil in the copaiba occasions more or less opacity in the liquid, and half the quantity causes the precipitation of white flakes in a few hours. (Stolze.) Turpentine, which is said to be sometimes added to copaiba, may be detected by its odor, especially if the copaiba be heated. According to Redwood, most of the proposed tests of the purity of copaiba are liable to fallacy, and the best measure of its activity is the quantity of volatile oil it affords by distillation. Castor oil, Venice turpentine, linseed oil, or gurjun balsam may be detected by means of petroleum benzin, which makes a clear solution with pure copaiba, but if either of the substances mentioned be present a milky mixture, which soon settles into two layers, is formed, the copaiba solution being on top. (A. J. P., July, 1873; Proc. A. Ph. A., xxiv, 191, xxvi, 286.) Maisch has found that ten volumes of petroleum benzin, instead of three as proposed by Wayne, must be added to one of copaiba to get the best results from this test. Indeed, it has been shown that pure copaiba will sometimes show turbidity when mixed with petroleum benzin. (A. J. P., 1877, p. 131.) Some years since, a substance was imported into New York, under the name of red copaiba, which did not possess a single characteristic of the genuine drug. It was of a thick, semi-fluid consistence, not unlike that of balsam of Tolu, as it often reaches us, of a brown color similar to that of the same balsam, though darker, and of an unpleasant yet somewhat aromatic odor, recalling that of liquidambar, but less agreeable. Its origin is unknown. Hager recommends the use of absolute alcohol, which he says completely dissolves, without turbidity, all the varieties of copaiba except the Para, whose solution on standing clears itself by the deposition of a few white flakes. J. M. Fulton asserts that some pure copaibas are not entirely dissolved by absolute alcohol. (A. J. P., 1877.) For additional tests and criticisms by Beckurts and Brueche, see A. Pharm., 1891, p. 90; also Proc. A. Ph. A., 1892, 635. For Hager's test, see C. D., 1894, 740. Dodge and Olcott (Am. Drug., 1895, 5) describe a test to detect gurjun balsam in copaiba, which Kebler regards as the most reliable yet proposed; it is as follows. Four drops of the suspected sample, dissolved in half a fluidounce of glacial acetic acid, will, if pure, remain colorless and clear, or but slightly cloudy, if from four to six drops of pure nitric acid be dropped into the solution. If the sample be pure gurjun balsam, the mixture will have a deep purple color; if a mixture of the two balsams, the depth of color will vary according' to the amount of the adulterant, as small a proportion as 2 per cent. being discoverable; a modification of this test is now official. (See also A. J. P., 1896, 143, and 1897, 394.) For a valuable paper on Copaiba by A. R. L. Dohme, see Proc. A. Ph. A., 1904, 322.
Uses.—Copaiba is gently stimulant, diuretic, laxative, and in very large doses often actively purgative. It produces, when swallowed, a sense of heat in the throat and stomach, and extends an irritant action not only throughout the alimentary canal, but also to the urinary passages, and in fact, in a greater or less degree, to the whole mucous membrane, for which it appears to have a strong affinity. The urine acquires a peculiar odor during its use, and its odor may be detected in the breath. It sometimes occasions an eruption upon the skin resembling that of measles, and attended with disagreeable itching and tingling, or even violent pemphigus. (N. Y. M. J., Jan., 1873, p. 416.) Nausea and vomiting, painful purgation, strangury and bloody urine, and a general state of fever are caused by excessive doses. As a remedy it has been found useful in catarrhs, particularly those of a chronic character. Thus, it is given with occasional advantage in leucorrhea, chronic cystitis, chronic diarrhea, hemorrhoids, and chronic bronchitis. The complaint, however, in which it is most employed is gonorrhea. It should not be administered in the first stages, when the inflammation is severe and acute, nor is it applicable to very chronic forms of the disorder, such as gleet. It was formerly much esteemed as a vulnerary and as an application to ulcers, but it is now seldom used externally. Ruschenberger recommends it locally in chilblains. (Med. Examiner, i, 77.)
Both the volatile oil and the resin are eliminated by the kidneys in an altered condition; if to the urine of a person taking the drug, nitric acid be added, a precipitate is thrown down, which may be mistaken for albumin. The volatile oil is more active than is the resin, which is not, however, inert. Wilks, of Guy's Hospital, London, speaks of the resin with great confidence as a hydragogue diuretic in obstinate dropsy, given in the dose of fifteen or twenty grains three times a day.
It may be given dropped on sugar, but in this form is often so exceedingly offensive as to render some concealment of its nauseous qualities necessary. A less disagreeable form is that of emulsion, prepared by rubbing the copaiba first with mucilage, or the yolk of an egg, and sugar, and afterwards with some aromatic water, as that of mint or cinnamon. The volatile oil, which is official in the British Pharmacopoeia, may be given in the dose of ten or fifteen minims (0.6-0.9 mil) in emulsion, or, as is almost universally preferred, in capsules.
Dose, of copaiba, from fifteen minims to a fluidrachm (1.0-3.75 mils) three times a day, or a smaller quantity repeated more frequently.
Off. Prep.—Massa Copaibae, N. F.; Mistura Copaibas, N. F.; Mistura Copaibae et Opii, N. F.; Oleum Copaibae, Br.