BALSAM OF PERU Bals. Peruv. [Peru Balsam]
"A balsam obtained from Toluifera Pereirae (Royle) Baillon (Fam. Leguminosae)." U. S. "Balsam of Peru is a viscid balsam exuded from the trunk of Myroxylon Pereirae, Klotzsch, after the bark has been beaten and scorched." Br.
Balsamum Peruvianum Nigrum, Balsamum Indicum; Baume des Indes, Baume de Perou noir, Baume de Sonsonate, Fr.; Balsamum peruvianium, P. G.; Peruvianischer Balsam, Indischer Balsam, Perubalsam, G.; Balsamo peruviano, Balsamo del Peru, It.; Balsamo del Peru liquido, Balsamo de San Salvador, Balsamo negro, Sp.
The origin of Peru balsam has been the subject of considerable investigation (see U. S. D., 19th ed.), and while the U. S. Pharmacopoeia in conjunction with the Swiss Pharmacopoeia ascribes it to Toluifera Pereirae, the British authority ascribes it to Myroxylon Pereirae. Tschirch, who has given a great deal of attention to the origin of Peru balsam, has come to the conclusion that it is merely a physiological variety of the same tree that yields Balsam of Tolu, and has designated it as Toluifera Balsamum, L., var. phys. Pereirae.
Toluifera Pereirae is a handsome tree, with a straight, round, lofty stem, a smooth ash-colored bark, and spreading branches at the top. The leaves are alternate, petiolate, and unequally pinnate. The leaflets are from five to eleven, shortly petiolate, oblong, oval-oblong, or ovate, about three inches long by somewhat less than an inch and a half in breadth, rounded at the base, and contracting abruptly at top into an emarginate point. When held up to the light they exhibit, in lines parallel with the primary veins, beautiful rounded and linear pellucid spots. The common and partial petioles and midribs are smooth to the naked eye, but when examined with a microscope are found to be furnished with short hairs. The fruit, including the winged footstalks, varies from two to four inches in length. At its peduncular extremity it is rounded or slightly tapering; at the top enlarged, rounded, and swollen, with a small point at the side. The mesocarp, or main investment of the fruit, is fibrous, and contains in distinct receptacles a balsamic juice, which is most abundant in two long receptacles or vittae, one upon each side. The yellowish-white beans yielded to Rother (P. J.) xv, 244) two per cent. of coumarin; the husks, a brown, extremely bitter, somewhat acrid resin. A gum-resin exudes in small quantities from the trunk of the tree, which, though containing, besides gum and resin, a small proportion of volatile oil, is distinct from the proper balsam, and yields no cinnamic acid. (Attfield, P. J., Dec., 1863.) The valuable wood of the tree resembles mahogany.
This tree grows in Central America, in the State of San Salvador, upon the Pacific coast. It is found in the wild forests, singly or in groups, but the trees are owned by individuals. Charles Dorat states that it is never found at a greater height on the mountains than one thousand feet, that it begins to be productive after five years, and continues to yield for thirty years or more, and that the aroma of its flower is perceived at the distance of one hundred yards. (A. J. P., xxxii.) The balsam is collected by the aborigines, on lands reserved to them, within a small district denominated the Balsam Coast, extending from Acajutia to La Libertad. Early in November or December the bark is beaten on four sides of the trunk, so as to separate it from the wood without breaking it, intermediate strips being left sound, in order not to destroy the life of the tree. The bruised bark soon splits, or cuts are made in it. Five or six days after the beating the injured surface is set on fire, and about a week later the bark, if it has not fallen off spontaneously, is removed. The juice now begins to exude freely from the exposed wood, which the natives cover with rags. The latter, when saturated, are boiled in water in large jars, and the liquid allowed to stand, whereupon the water rises to the top, and is poured off, leaving the balsam, which is put into calabashes or bladders. Seven to ten days later a second flow of balsam occurs, and is secured as before. Subsequently the exposed parts are scraped or otherwise wounded, and a third balsam is obtained. These three grades of balsam are said to be known respectively as Tagauzonte, balsam de trapo, balsamo de contrapique. The balsam is then taken for sale to the neighboring towns, where it is purified by subsidence and straining and put into jars or metallic drums for exportation. The destroyed bark is said to renew itself in two years, so that by care a tree can be worked for a long time; two pounds is stated to be the average yearly yield. In 1861 the tree was introduced in Ceylon with complete success.
The term Balsam of Peru is a survival of the times when the products of the Spanish colonial coast were assembled at Callao, Peru, for shipment to Europe. This fact has caused Gane and Webster to assert that Balsam of Peru is mis-branded under the Foods and Drugs Act in that it does not come from Peru. (Drug Topics, 1910, p. 4.) It is estimated that the Republic of Salvador exports annually about 130,000 pounds of Balsam of Peru. In spite of this there is a good deal of factitious balsam on the market which consists chiefly of synthetic cinnamein which is often added to exhausted tolu. Riedel reports having found a sample of balsam on the market, which was apparently derived from Myroxylon punctatum Klotzsch, and which contained none of the active principles of Balsam of Peru.
A substance called white balsam (Balsamo blanco) is procured from the fruit. This has been confounded with the balsam of Tolu, but is wholly distinct. It is of a semi-fluid or soft-fluid consistence, somewhat granular, and, on standing, separates into white, resinous crystalline deposit, and a superior, translucent more fluid portion. The odor, though quite distinct from that of the balsams of Tolu and Peru, is not disagreeable. Stenhouse has obtained from it a peculiar resinous body, readily crystallizable, and remarkably indifferent in its chemical affinities, which he denominated myroxocarpin. (P. J., x, 290.) Tschirch (Harze und Harzbehälter, 1900, p. 166) gives the compound the name myroxoresene, and the formula, C7H10O. Dorat, however, denies that the white balsam is produced by the same tree, or in the same vicinity.
Another substance obtained from the same tree, and much used in Central America, is a tincture of the fruit made by digesting it in rum. It is called balsamito by the inhabitants, and is said to be stimulant, anthelmintic, and diuretic. It is also used as an external application to gangrenous or indolent ulcers, and as a wash to the face to remove freckles. According to Dorat, the balsamito is not the tincture, but an alcoholic extract of the young fruit. Neither this nor the white balsam reaches the markets of this country.
Balsam of Peru was named from its place of exportation, and it was long thought to be a product of Peru. It is now shipped partly from the Pacific coast, and partly from the Balize or other Atlantic ports, whither it is brought across the country. It was Guibourt who first made known the fact of its exclusive production in Central America. As imported, it is usually in tin canisters, with a whitish scum on its surface, and more or less deposit, which is dissolved with the aid of heat.
Besides the official species, there are others of the genus which possess medicinal virtues, and have been more or less employed. (See 14th ed., U. S. D.) The pod of M. frutescens Jacq., growing in Trinidad, is popularly used in that island as a carminative, and externally, in the form of a tincture, as a lotion in rheumatic pains, and by incisions in the stem a small quantity of balsamic juice is obtained not distinguishable from balsam of Tolu. (P. J., Sept., 1862, p. 108.) Another species is known in Paraguay under the name of quino-quino, the bark of which is used, in powder and decoction, as a remedy in wounds and ulcers, and from the trunk of which a juice is obtained which in its concrete state closely resembles dried balsam of Peru. (P. J., Oct., 1862, p. 183.) A product of T. peruiferum, sometimes known as Brazilian balsam or as Oleo-balsam has been offered for sale as genuine Peru balsam. In bulk it is of a dark brown color, but in thin layers it is dark red. Its odor is smoky, feebly fragrant; its taste slightly pungent, leaving a choking, disagreeable, persistent feeling. It is entirely soluble in ether and in rectified spirits. It also mixes with castor oil in all proportions, and forms with carbon disulphide a clear light brown solution with residue, also a deposit, in its chloroform solution, which becomes a powdery precipitate upon standing. At 17° C. (62.6°F.) its specific gravity is 1.031. Its general constitution is very similar to that of balsam of Peru, containing volatile oil, myroxylin, cinnamic and tannic acids, and resin. (P. J., 3d ser. xi, 818.) It is especially to be distinguished from Peru balsam by its behavior with sulphuric acid. When Peru balsam is treated with sulphuric acid, and cold water poured upon it, a beautiful violet color is imparted to the surface, and the whole mass has a bright shade. The same procedure yields with the oleo-balsam a gray mass. For further information, see P. J., xv, 771.
Properties.—"Balsam of Peru is a viscid liquid of a dark brown color; free from stringiness or stickiness; transparent and reddish-brown in thin layers; of an agreeable, vanilla-like odor and a bitter, acrid taste, with a persistent after-taste. When swallowed it leaves a burning sensation in the throat. It does not harden on exposure to the air. It is soluble in alcohol, chloroform, and glacial acetic acid with not more than a slight opalescence; only partly soluble in ether or petroleum benzin. Water, when agitated with the Balsam, is acid to litmus. Specific gravity: 1.130 to 1.160 at 25° C. (77° F.). One Gm. of the Balsam forms a clear solution when shaken with a solution of 3 Gm. of hydrated chloral in 2 mils of distilled water (fixed oils). Shake about 1 Gm. of the Balsam with 5 mils of purified petroleum benzin, and warm the mixture on a water bath for 10 minutes, adding a sufficient quantity of the solvent to replace the loss by evaporation. On evaporating 2 mils of the benzin solution, no odor of turpentine is noticeable, and when the residue is treated with a. few drops of nitric acid, no green or bluish color is produced (turpentine or rosin). Weigh accurately about 1 Gm. of the Balsam and dissolve it in 100 mils of alcohol, add 1 mil of phenolphthalein T.S. and titrate the solution with half-normal potassium hydroxide V.S. The acid number thus obtained is not less than 56 nor more than 84. Mix about 3 Gm. of the Balsam, accurately weighed, with 30 mils of sodium hydroxide T.S. and shake the mixture for a few minutes with 60 mils of ether. Then add about 3 Gm. of powdered tragacanth, filter and transfer 50 mils of the ethereal filtrate (representing five-sixths of the weight of the Balsam taken) into a tared, conical flask. Evaporate the ether and dry the residue to constant weight at 100° C. (212° F.). The weight of the residue of cinnamein so obtained is not less than 50 per cent. nor more than 56 per cent. of the weight of the Balsam represented by the 50 mils of ethereal solution taken. Dissolve this residue in 25 mils of alcohol, add 25 mils of half-normal alcoholic potassium hydroxide V.S. and heat the mixture carefully in a flask provided with a reflux condenser, during half an hour on a water bath. Then add 1 mil of phenolphthalein T.S. and titrate the excess of alkali with half-normal hydrochloric acid V.S. The amount of half-normal alcoholic potassium hydroxide V.S. consumed corresponds to a saponification value for the cinnamein of from 235 to 238 (see Part III, Test No. 10)." U.S.
"A viscid liquid, in bulk nearly black but in thin layers deep orange-brown or reddish-brown and transparent. Agreeable balsamic odor, taste acrid, leaving when swallowed a burning sensation in the throat. Insoluble in water; soluble in chloroform. 1 volume is soluble in 1 volume of alcohol (90 per cent.), but on the further addition of 2 or more volumes of the alcohol the mixture becomes turbid. Specific gravity between 1.140 and 1.158. Does not diminish in volume when shaken with an equal bulk of water (absence of ethylic alcohol). When tested by the following method it yields not less than 57 per cent. of cinnamein, the saponification value of which is not less than 235:—Dissolve 1 gramme of the Balsam in 30 millilitres of ether and shake in a separating funnel with two successive quantities of 20 and 10 millilitres of N/2 solution of sodium hydroxide. Separate the alkaline solutions, mix and shake with 10 millilitres of ether. Draw off and reject the alkaline solution. Add the second ethereal solution to that previously obtained. Wash the mixed ethereal solutions with two successive quantities of 5 millilitres of water. Transfer the ethereal solution thus washed to a tared wide-mouthed flask, evaporate at a gentle heat until the odor of ether has disappeared, add 1 millilitre of absolute alcohol, dry at 100° C. (212° F.) for half an hour, and weigh. The weight of the cinnamein thus obtained is not less than 0.57 gramme. To this residue add 20 millilitres of N/2 alcoholic solution of potassium hydroxide and 20 millilitres of alcohol (90 per cent.). Attach a reflux condenser, boil for half an hour, and titrate back with N/2 solution of sulphuric acid, solution of phenolphthalein being used as indicator. Each gramme of the residue thus treated requires not less than 8.4 millilitres of the alkaline solution for complete saponification (corresponding to a saponification value of not less than 235)." Br.
Boiling water extracts the acid. The oily liquid which separates on agitating Peru balsam with potassium or sodium hydroxide, called Peru balsam oil by Stoize, and cinnamein by Fremy, may be separated by fractional distillation into three portions, viz., benzyl alcohol, C7H8O, passing- over at about 200° C. (392° F.); benzyl benzoate, C7H5O2.C7H7, the principal portion boiling at 303° to 304° C. (577.5°-5790 F.); and benzyl cinnamate, C9H7O2.C7H7, passing over at about the boiling point of mercury. The crude oil likewise contains small quantities of free cinnamic and benzoic acids, resulting from the decomposition of the benzylic ether by the alkali used in separating it. According to Kraut (Ann. Ch. Ph., cliii, p. 129), the benzyl cinnamate constitutes nearly 60 per cent. of the balsam; but Trog (A. Pharm., 1894, 70-98) states that it is the benzyl benzoate which makes up the bulk of the oily portion and amounts to from 63 to 64 per cent. Tschirch (loc. cit.) states tliat in the sample of Peru balsam investigated by him benzyl benzoate was the main constituent, but small amounts of benzyl cinnamate were also present, and he considers that the relative proportions of the two esters may vary greatly in different samples of the balsam. The odor of the balsam Tschirch considers to be due to the peruviol, C13H22O, discovered by Thoms.
Peru balsam appears to contain only a single resin, yielding, by analysis, 66.3 to 67.25 per cent. of carbon, and 6.22 to 6.32 per cent. of hydrogen. (Kraut, loc. cit.) This resin separated from the alkaline solution of the balsam by hydrochloric acid is brown, has a faint odor of vanilla, and when fused with potash yields protocatechuic acid, together with a little benzoic acid. Tschirch has studied this resin and finds it to be the cinnamic ester of an alcoholic body called peru-resino-tannol, with the formula C6H5.CH.COOC18H19O4. The tree also exudes a gum-resin, which, according to Attfield (P. J., 1864, p. 248), contains 77.4 per cent. of a resin, and is non-aromatic, devoid of cinnamic acid, and entirely distinct from balsam of Peru. The leaves of the tree contain a fragrant oil. Like benzoin, balsam of Peru appears to be a pathological product.
The balsam is said to be adulterated in Europe (especially at Bremen) with castor oil, copaiba, Canada turpentine, etc. (P. J., xii, 549), and a factitious substance has been sold in this country for the genuine balsam, prepared by dissolving balsam of Tolu in alcohol. This may be distinguished by its taking fire readily and burning with a blue flame, but a skillfully prepared product known commercially as Perugen is furnished, of which K. Enz (1913) states that the only constants of the German Pharmacopoeia available for detection are the acid number, iodine number, isolated cinnamein nitric acid reaction, and behavior in contact with benzin; the other pharmacopoeial constants are of no value. "Synthetic Balsam of Peru" (Ph. Ztg., No. 79, 828), is defended by Dr. F. Evers on the ground that it is equivalent to the natural balsam therapeutically and in some respects superior. Caesar and Soretz state that the characteristic odor and taste of the natural balsam are absent in the substitute.
For additional tests, see Proc. A. Ph. A., 1894, 903; also 1895, 866, and D. C., 1898, 60. A method of detecting castor oil, proposed by Wagner, is to expose a small portion of the suspected balsam to distillation until somewhat more than one-half has passed, shake the distillate with baryta water, remove by means of a pipette the layer of oil floating on the surface, and shake this with a concentrated solution of sodium bisulphite. If castor oil be present, the liquid will immediately become a crystalline mass. (A. J. P., xxx, 570.)
A color test to distinguish true Peru Balsam from the factitious variety is as follows: One drop of Peru Balsam is shaken with 5 mils of petroleum benzin, and to 2.5 mils of this liquid 5 mils of ether is added. Sulphuric acid is then added, drop by drop, until from 10 to 15 drops have been added. Genuine Peru Balsam gives a beautiful violet to cornflower blue color in the lower layer, while the artificial products give either no color or very different shades.
Flückiger relied upon the specific gravity, which should be between 1.140 and 1.145, and the lime test, in which 10 drops of the balsam are shaken with 6 grains (0.4 Gm.) of slaked lime, forming, if there be no adulteration, a soft mixture, which does not harden. Grote's test consists in shaking 3 drops of balsam with 2 mils of official ammonia water; if, after standing, the mixture solidifies, rosin or other adulterant is present; benzoin, storax, and certain other substances cannot be detected by this test. (A. J. P., 1881, 302, 361.)
As stated by Trog and others, the percentage of cinnamein should approximate 60. The saponification number should be between 235 and 238.
Uses.—Balsam of Peru is useful internally as a stimulating expectorant in asthma and chronic bronchitis, especially when of tuberculous origin. Although not so agreeable as balsam of Tolu it is much more active. Externally it affords a valuable stimulating dressing in indolent ulcers and local tuberculosis of the skin, bone, larynx, etc. It has also been highly lauded by Malannik (M. M. W; 1912) as a first dressing for military wounds. He asserts that it is not only bactericidal of itself but that it stimulates the local resistance of the tissues and that it exercises a valuable protective action. Extensive erythema has followed its local application. (Hazen, J. A. M. A., 1910, liv.) Internally it is best administered suspended in water by the yolk of egg or acacia.
Dose, from five to fifteen minims (0.3-0.9 mil).
Off. Prep.—Mistura Oleo-Balsamica, N. F.