Resina Draconis.—Dragon's Blood.
A resin derived from the fruit of Calamus Draco, Willdenow (Daemonorops Draco, Blume).
Botanical Source.—Calamus Draco is a small palm growing in the islands of the Indian archipelago. While the plants are young the trunk is erect, and resembles an elegant, slender palm tree, armed with innumerable dark-colored, flattened elastic spines, often disposed in oblique rows, with their bases united. By age they become scandent, and overrun trees to a great extent. The leaves are pinnate, their sheaths in petioles armed as above described; leaflets single, alternate, ensiform, margins remotely armed with stiff, slender bristles, as are also the ribs; 12 to 18 inches long and about 3/4 inch broad. The spadix of the female is hermaphrodite and inserted by means of a short, armed petiole on the mouth of the sheath opposite to the leaf, and is oblong and decompound, resembling a common oblong panicle. Spathes several, one to each of the 4 or 5 primary ramifications of the spadix, lanceolate and leathery; all smooth except the exterior or lower one, which is armed on the outside. Calyx turbinate, ribbed, mouth 3-toothed, by the swelling of the ovary split into 3 portions, and in this manner adhering, together with the corolla, to the ripe berries. Corolla 3-cleft; divisions ovate-lanceolate, twice as long as the calyx, and permanent. Filaments 6, very broad, and inserted into the base of the corolla. Anthers filiform, and seemingly abortive. Ovary oval; style short; stigmas 3-cleft; divisions revolute and glandular on the inside. The berry is round, pointed, and of the size of a cherry (L.—Roxb.).
History and Description.—Dragon's blood is a dark-red substance, which is imported from the East Indies, and which is procured from the berries of the Calamus Draco, by rubbing or agitating them in a bag, softening by heat the resinous exudation obtained, and making this up into masses. An inferior grade is obtained by boiling the crushed fruits in water (Pharmacographia). There are several sorts of it, one (Red dragon's blood), occurring in dark reddish-brown sticks, a foot or more in length, and from 3 to 6 lines in diameter, enveloped with palm leaves, and bound with narrow slips of cane; another occurs in reddish-brown lumps of the size and shape of an olive, also covered with leaves in a moniliform row; another, of very fine quality, is a reddish powder; a fourth occurs in large, irregular pieces or tears, while an inferior kind is in very large masses or lumps, Lump dragon's blood, presenting a heterogeneous fracture (P.). Dragon's blood is brittle, feebly sweetish, or almost tasteless, and odorless. It is not acted upon by water, but is almost all dissolved by alcohol, wood alcohol and ether, only impurities being left undissolved; partly soluble in chloroform and benzene. It fuses by heat, and emits a benzoic-acid-like fume on burning. Its solution stains marble a fine deep-red color.
Chemical Composition.—Herberger found dragon's blood to consist chiefly of a red resin (90.7 per cent) which he called draconin. He also established the presence of benzoic acid. Hlasiwetz and Barth by fusing dragon's blood with caustic potash obtained benzoic, para-oxy-benzoic, oxalic and probably protocatechuic acids. E. Hirschsohn (Jahresb. der Pharm., 1877, pp. 54 and 404) established the behavior of genuine dragon's blood toward solvents and reagents. It is soluble in alcohol and ether with red color, less so in chloroform; if the article is derived from Pterocarpus Draco of the West Indies, it will be but little soluble in chloroform. Petroleum ether abstracted only from 1 to 7 per cent of soluble matter. Dragon's blood, in connection with other resins, was investigated in recent years by Prof. Tschirch and his pupils. K. Dieterich (Jahresb. der Pharm., 1896, p. 159) examined a specimen derived from Daemonorops Draco (Java and Sumatra) and found it to contain: (1) Dracoalban (2.5 percent) an amorphous indifferent, not fusible body, abstracted by ether and precipitated by alcohol; it has the formula, C20H40O4; (2) dracoresin (13.58 per cent) soluble in petroleum ether, alcohol, and ether, of the formula, C20H44O2, fusing at 74° C. (165.2° F.); (3) red resin (56.8 per cent), a mixture of two esters, namely, compounds of the alcohol, C8H10O2 (dracoresino-tannol) with benzoic acid (C6H5.COOH) and with benzoyl acetic acid (C6H5.CO.CH2.COOH); (4) a resin soluble in alcohol, insoluble in ether (0.33 per cent); (5) phlobaphenes (0.03 per cent); (6) woody fragments, etc. (18.40 per cent); (7) ash (8.30 per cent). Draco-resino-tannol yields, upon dry distillation, benzene (benzol), toluene, styrol, phenyl acetylene, phenol, resorcin, pyrogallol, phloroglucin, acetic acid and creosote.
Action, Medical Uses, and Dosage.—Dragon's blood was formerly considered an astringent, and used in doses of from 10 to 30 grains in passive hemorrhages, diarrhoea, etc. Its principal use is to color tooth powders, plasters, tinctures and varnishes, and to produce a mahogany wood-stain (aloes 1 part, dragon's blood 1 part, alcohol 15 parts).
Related Drugs.—SOCOTRA DRAGON'S BLOOD, or Katir, is the product of Dracaena Schizantha, Baker, or, according to Hunter, the Dracaena Ombet of Kotschy. It is produced in Socotra. It differs from the Sumatra drug in the absence of scales, and in not evolving benzoic acid vapors when heated (Pharmacographia).
CANARY ISLAND DRAGON'S BLOOD is the product obtained by incising the stem of Dracaena Draco, Linné, of the Canary Isles. Pterocarpus Draco, Linné, of West Indies and South America, yields a resin known also as dragon's blood, as does Croton Draco, Schlechtendal, the product of the latter, however, being more of the nature of kino (Pharmacographia). According to Prof. H. Trimble (Amer. Jour. Pharm., 1895, p. 516), a specimen received from Jamaica was for the most part soluble in warm water and contained 46.7 per cent of tannin, referred to dry substance, hence it closely resembled kino. The foregoing are not in general commerce. (For an analytical study of the various red resins known as dragon's blood, see J. J. Debbie and G. G. Henderson, Amer. Jour. Pharm., 1884, p. 327).