Guaiaci Lignum. Guaiacum Wood, Lignum Sanctum, Lignum Vitae. Guaiacum officinale, Guaiacum sanctum. Guaia.
Guaiaci Lignum. Br.
"Guaiacum Wood is the heart-wood of Guaiacum officinale, Linn., or of Guaiacum sanctum, Linn." Br. "The heart-wood of Guaiacum officinale Linne or of Guaiacum sanctum Linne (Fam. Zygophyllaceae)" N. F.
Lignum Sanctum (vel Benedictum); Lignum Vita, Gayac, Fr. Cod.; Bois de Gayac, Fr.; Lignum Guajaci, P. G.; Guajakholz, Franzosenholz, Pockholz, G.; Guajaco, Legno guajaco, It.; Guayaco (Lefio de), Sp.
Guaiacum officinale is a large tree, of a very slow growth. When of full size it is from forty to sixty feet high, with a trunk four or five feet in circumference. The branches are knotted, and covered with an ash-colored striated bark. That of the stem is of a dark-gray color, variegated with greenish or purplish spots. The leaves are opposite, and abruptly pinnate, consisting of two, three, and sometimes four pairs of leaflets, which are obovate, veined, smooth, shining, dark green, from an inch to an inch and a half long, and almost sessile. The flowers are of a rich blue color, stand on long peduncles, and grow to the number of eight or ten at the axils of the upper leaves. The seeds are solitary, hard, and of an oblong shape.
G. sanctum L. is distinguished from G. officinale by its five-celled fruit and its oblong or obliquely obovate or sometimes rhomboid-ovate leaflets, six to eight to each leaf. It grows in Cuba, the Bahama Islands and Florida. Its wood is smaller than that of G. officinale, and is said by Fee to be paler and less dense.
The commercial supplies are shipped from the Bahama Islands and Florida to London, Hamburg and Havre.
G. officinale grows throughout tropical America, particularly in the Lesser and Greater Antilles, also in Brazil, Venezuela and Colombia. The commercial drug is exported from Port au Prince, Puerto Plata and St. Domingo, also Savanilla (Colombia) and Puerto Cabello (Venezuela). G. arboreum of De Candolle has been said to furnish some of the guaiacum wood of commerce.
As imported, guaiac wood is in the shape of logs or billets, covered with thick gray bark, which presents on its inner surface, and upon its edges, when broken, numerous shining crystalline particles. These were supposed by Guibourt to be benzoic acid, by others a resinous exudation from the vessels of the plant; but Otto Berg has determined that they are crystals of calcium sulphate. The billets are used by turners for the fabrication of various instruments and utensils, for which the wood is well adapted by its extreme hardness and density. It is sometimes kept by pharmacists in the state of shavings or raspings, which they obtain from the turners. It is commonly called lignum vitae, a name which obviously originated from its durable properties.
Properties.—Guaiacum wood is hard and heavy. The color of the sap-wood is yellow, that of the older and central layers greenish-brown, that of the shavings a mixture of the two. It is said that when the wood is brought into a state of minute division its color is rendered green by exposure to the air, and bluish-green by the action of nitric acid fumes, and the latter change may be considered as a test of its genuineness. (Duncan.) An easier test is a solution of corrosive sublimate, which, added to the shavings and slightly heated, causes a bluish-green color in the genuine wood. Guaiacum wood is almost without odor unless rubbed or heated, when it becomes odorous. When burned, it emits an agreeable odor. It is bitterish and slightly pungent, but requires to be chewed for some time before the taste is developed.
"Dark greenish-brown, dense, hard; heavier than water. In transverse section, abundant sclerenchymatous fibres, scattered, isolated vessels, and medullary rays one cell wide. Odor, on warming, somewhat aromatic; taste slightly acrid. An alcoholic tincture prepared from the Wood assumes a blue color on the addition of diluted T. Sol. of ferric chloride." Br.
The N. F. IV describes it as follows: "Usually in the form of shavings, chips or raspings of a greenish-brown color, heavier than water, entirely free from adhering bark and containing only a few chips or shavings of a whitish color (sap wood). Almost odorless except when heated; taste bitter and acrid when chewed for some time. The powder, when examined under the microscope, exhibits numerous fragments of more or less lignified, thick-walled wood fibers, up to 0.028 mm. in width, some with simple, oblique pores; tracheae from 0.09 to 0.16 mm. in width, some filled with resin; numerous small masses of resin; wood parenchyma and medullary ray cells up to 0.02 mm. in width, with lignified, porous walls and usually containing resin; occasionally tangential views of the medullary rays show an elliptical group of from three to six cells; the resin masses and resinous tissue become bluish-green on the addition of iodine T.S. Place powdered Guaiac Wood in a solution of sodium chloride (1 in 3); the blackish-brown part only will sink and this does not exceed in amount the portion which floats. Shake 10 mils of alcohol with 0.5 Gm. of ground Guaiac Wood for a few seconds and filter the mixture; the filtrate yields a deep blue color with one drop of a solution of ferric chloride (1 in 10). Guaiac Wood yields to alcohol not less than 15 per cent. of extractive. Guaiac Wood yields not more than 3 per cent. of ash." N. F.
Guaiac wood contains, according to Trommsdorf, 26 per cent. of resin, and 0.8 of bitter pungent extractive, upon both of which, probably, though chiefly on the former, its medicinal virtues depend. (See Guaiacum.) Paetzold (Schim Rep., 1902, 43) states that the bark of the guaiac tree yields 1 per cent. of a volatile oil, having an exquisite odor. The wood yields its virtues but slightly to water. One pound of the wood afforded to Geiger two ounces of extract.
Uses.—Guaiacum wood possesses no therapeutic powers which are not contained in its resin and the latter is always to be preferred.
Dose, thirty to sixty grains (2.0-3.9 Gm.).
Off. Prep.—Decoctum Sarsaparillae Compositum, N. F.
Guaiacum. U. S. (Br.)
Guaiac. Guaiac. [Guaiaci Resina, Pharm. 1890, Guaiac Resin]
"The resin of the wood of Guaiacum officinale Linne, or of Guaiacum sanctum Linne (Fam. Zygophyllaceae)." U. S. "Guaiacum Resin is the resin obtained from the stem of Guaiacum officinale, Linn., or of Guaiacum sanctum, Linn." Br.
Guaiaci Resina, Br., Guaiacum Resin; Resine de Gayac. Fr. Cod.; Resina Guajaci, P. G.; Guajak, Guajakharz, G.; Resina de guajaco, It.; Resina de guayaco, Sp.
For a description of Guaiacum officinale, see Guaiaci Lignum.
Guaiac resin was introduced into the London Pharmacopoeia in 1677. It exists in the tree as a physiological product filling up the tissues of the wood. It is obtained in several different modes. The most simple is by spontaneous exudation, or by incisions made into the trunk. Another method is by sawing the wood into billets about three feet long, boring them longitudinally with an auger, then placing one end of the billet on the fire, and receiving in a calabash the melted guaiac, which flows out through the hole at the opposite extremity. But the plan probably most frequently pursued is to boil the wood, in the state of chips or sawdust, in a solution of common salt, and skim off the substance which arises to the surface. Guaiac is chiefly produced in the eastern portion of the Island of Haiti, being exported from Port au
Prince and Gonaives. (Ap.-Ztg., xxv, p. 556.) It is estimated that in 1912 about 6000 pounds of guaiac resin were exported to the United States. It is usually in large irregular pieces of various sizes, in which small fragments of bark, sand, and other impurities are mixed with the genuine guaiac, so as to give to the mass a diversified appearance. Sometimes it is found in small roundish homogeneous portions, separate or agglutinated; sometimes in homogeneous masses, prepared by melting and straining the drug in its impure state. It is probable that the guaiac obtained from the billets in the manner above described is of uniform consistence.
Properties.—The masses are irregular or somewhat globular, of a glassy luster and resinous fracture. They are of a deep greenish-brown or dark-olive color on their external surface, and internally wherever the air can penetrate. The predominant hue of those parts not exposed to the air is reddish-brown or hyacinthine, diversified, however, with shades of various colors. The odor is feeble but fragrant, and is rendered stronger by heat. The taste, which is at first scarcely perceptible, becomes acrid after a short period, and a permanent sense of warmth and pungency is left in the mouth and fauces. Guaiac is brittle, and when broken presents a shining glass-like surface, conchoidal or splintery, with smaller fragments more or less translucent. It is readily pulverized, and the powder, at first of a light-gray color, becomes green on exposure to the light. Its sp. gr. varies from 1.2 to 1.23. It softens in the mouth, and melts with a moderate heat. Water dissolves a small proportion of guaiac, not exceeding nine parts in 100, forming an infusion of a greenish-brown color and sweetish taste, which upon evaporation yields a brown substance soluble in hot water and alcohol, but scarcely so in ether. Alcohol takes up the whole, with the exception of impurities. The official requirements are as follows: "In irregular fragments or in large, nearly homogeneous masses, occasionally in more or less rounded or ovoid tears, enclosing fragments of vegetable tissues; externally brown, becoming greenish-gray-brown on exposure, the fractured surface having a glassy luster, the thin pieces being translucent and varying in color from reddish to yellowish-brown; odor balsamic; taste slightly acrid. Guaiac melts between 85° and 90° C. (185° and 194° F.). It is readily soluble in alcohol, ether, chloroform, creosote, and in solutions of the alkalies or in hydrated chloral T.S. It is sparingly soluble in carbon disulphide or benzene and not more than 15 per cent. is insoluble in alcohol; the alcoholic solution, on the addition of an excess of chlorine water or tincture of ferric chloride, becomes blue, changing quickly to green, the color being best seen when the solutions are diluted with an equal volume of water. Macerate the crushed or powdered Guaiac with 4 or 5 times its weight of purified petroleum benzin for three hours and then filter; the filtrate is colorless, and does not give a green color on the addition of an equal volume of cupric acetate T.S. (rosin). The powder is grayish, becoming green on exposure to the air. Guaiac yields not more than 4 per cent. of ash." U. S.
"In masses, or sometimes in large more or less rounded tears. Brittle; fracture vitreous; thin splinters transparent, from yellowish-green to reddish-brown. Powdered Resin greyish, but becoming green on exposure to light and air. Odor, on warming, somewhat aromatic; taste slightly acrid. A solution in alcohol (90 per cent.) is colored blue by diluted T. Sol. of ferric chloride. 1 gramme of the powdered Resin, shaken for five minutes with 5 millilitres of petroleum spirit, yields a colorless filtrate which does not become green when shaken with an equal volume of diluted solution of copper acetate (absence of colophony). Not more than 10 per cent. insoluble in alcohol (90 per cent.). Ash not more than 4 per cent." Br.
The tincture is of a deep-brown color, is decomposed by water, and affords blue, green, and brown precipitates with the mineral acids. It is colored blue by nitric acid, by chlorine, and by tincture of ferric chloride, and usually by spirit of nitrous ether, and is similarly changed when treated successively by diluted hydrocyanic acid and solution of copper sulphate. Either in substance or tincture, guaiac gives a blue color to gluten and substances containing it, to mucilage of gum arabic, to milk, and to various freshly cut roots, as to the potato, carrot, and horseradish. This is on account of the fact that oxidizing enzymes or oxidases are present in all of these substances and guaiac resin is one of the most delicate reagents for detecting this class of enzymes. It is soluble also in ether, alkaline solutions, and sulphuric acid. The solution in sulphuric acid is of a rich claret color, deposits, when diluted with water, a lilac precipitate, and, when heated, yields charcoal. Exposed to air and light, guaiac absorbs oxygen and becomes green, and the change takes place rapidly in the sunshine. Schaer states that a good natural guaiac resin is preferable to a resin purified by alcoholic treatment as a reagent, but a solution of resin extracted by chloroform from the wood is the most sensitive of all. Tincture of guaiac has been used for the detection of blood stains, which it does by the blue color produced by it, when in contact with the red coloring matter of blood, in connection with some ozonized substance, especially hydrogen dioxide. R. M. Bertolet (Am. J. M. S., Jan., 1874) has used it to distinguish between the blood of man and other mammals, in which the corpuscles are non-nucleated, from that of other classes, as birds, fishes, and reptiles, which have nucleated corpuscles.
Lucker (Proc. A. Ph. A., 1894, 953), finds in guaiac three acids,—viz., guaiacic, C20H24O4, occurring in crystals melting at 86 C. (186.8° F.); guaiaconic, C20H24O5. an amorphous body melting at from 81° to 83° C. (177.8°-181.40 F.); and guaiacinic, C21H22O7. He considers all three of them to be probably condensation products from tiglic aldehyde with creosol and guaiacol. Dobner has also determined that these three acids form a series of hydroxyl-containing acids which may be represented by the formulas: C20H23O3(OH), C20H22O3(OH)2 and C21H19O4(OH)3. (Tschirch, Harze und Harzbehalter, 1900, p. 300.) Guaiac yellow, the coloring matter of guaiac resin, was first observed by Pelletier. It crystallizes in pale yellow quadratic octahedra having a bitter taste, but is not a glucoside. Guaiac resin also yields interesting products on dry distillation. First, according to Hlasiwetz, is obtained guaiacene, C5H8O, at 118° C. (244.4° F.), next guaiacol,
being the methyl ether of pyrocatechin, at 205° to 210° C. (401°-410° F.),and with it kreosol, C6H3(CH3)2OH, and finally pyroguaiacin, C38H44O6 (according to Wiesner, C18H18O3), in pearly scales, melting at 180° C. (356° F.). According to Lieben and Zeisel (Ber. d. Chem. Ges., xiv, p. 932), guaiacene is the aldehyde of tiglic acid, C5HsO2, and can be made synthetically from a mixture of acetaldehyde and propional-dehyde. When distilled with zinc dust there is obtained creosol (50 per cent. in the case of resin purified by alcohol) and 30 per cent. of a mixture of toluene, meta- and paraxylene, with a little pseudocumene and guaion, C12H12.
Saponin has been found by E. Paetzold in the bark, the wood, and the natural resin of guaiacum. (Bull. des Sciences Pharm., iii, 407.) According to the experiments of W. Frieboes (In. Dis., Rostock, 1903), this saponin (1 to 1000) forms a frothing solution which is persistent, is an excellent emulsifier, has the power to maintain in solution large proportions of sparingly soluble substances and is innocuous and non-irritant.
The mineral acids are incompatible with the solutions of guaiac.
Adulterations.—This drug is sometimes adulterated with the rosin of the pine. The fraud may be detected by the terebinthinate odor exhaled when the sophisticated guaiac is thrown upon burning coals, as well as by its partial solubility in hot oil of turpentine. This liquid dissolves rosin, but leaves pure guaiac untouched. Amber was said to be another adulterant at one time. Nitric acid affords an excellent test of guaiac. If paper moistened with the tincture be exposed to the fumes of this acid, it speedily becomes blue. Purgotti proposed guaiac resin as a test for copper. (See A. J. P., June, 1880.)
Uses.—Guaiac, like many other resinous substances, is stimulant and alterative. If given to a patient when covered warm in bed, and accompanied with hot drinks, may assist in exciting perspiration, and hence it has been ranked among the diaphoretics. In large doses it purges, and it has been especially commended as a laxative in chronic rheumatism, and it is thought by some practitioners to be possessed of emmenagogue powers. It has been given in chronic rheumatism, gouty affections, secondary syphilis, scrofulous diseases, and cutaneous eruptions, but is of doubtful service. The medicine is given in substance or tincture. The dose of the powder is from ten to thirty grains (0.65-2.0 Gm.), which may be exhibited in pill or bolus, in the shape of an emulsion formed with gum arable, sugar, and water, or as a syrup. An objection to the form of powder is that it quickly aggregates. Guaiac is sometimes administered in combination with alkalies, with which it readily unites. The ammoniated tincture of guaiac is a preparation of this kind. Several European Pharmacopoeias direct a soap of guaiac, under the name of sapo guaiacinus, to be prepared by .diluting solution of potassium hydroxide with twice its weight of water, boiling lightly, then adding guaiac gradually, with continued agitation, so long as it continues to be dissolved, and finally filtering, which was followed by evaporating to the pilular consistence.
T. C. Craig (A. J. P., July, 1880) recommends a Syrup of Guaiac made as follows: Powd. Guaiac Resin, 640 grains; Caustic Potassa, 58 grains; White Sugar, 1 lb. (av.); Water, q. s. Dissolve the Potassa in 8 fluidounces of water; moisten the Guaiac with this solution; pack it in a percolator, and gradually pour on the remainder of the solution; when this ceases dropping, add sufficient water to make the percolate measure 8 fluidounces; add the sugar, and dissolve.
Dose, from ten to thirty grains (0.65-2.0 Gm.).
Off. Prep.—Mistura Guaiaci, Br.; Pilula Hydrargyri Subchloridi Composita, Br.; Tinctura Guaiaci, U. S.; Tinctura Guaiaci Ammoniata, U. S., Br.; Trochiscus Guaiaci Resinae, Br.; Gargarisma Guaiaci Compositum, N. F.; Glyceritum Guaiaci, N. F.; Mistura Guaiaci (from Tincture), N. F.; Pilulae Antimonii Compositae, N. F.; Tinctura Guaiaci Composita, N. F.