Benzoinum (U. S. P.)—Benzoin.

Preparations: Tincture of Benzoin - Compound Tincture of Benzoin - Ointment of Benzoin
Related entry: Acidum Benzoicum (U. S. P.)—Benzoic Acid- Lindera.—Spice-Bush

"A balsamic resin obtained from Styrax Benzoin, Dryander"—(U. S. P.)
Nat. Ord.—Styraceae.
COMMON NAMES: Benzoin, Gum benzoin, Gum Benjamin.
ILLUSTRATION: Bentley and Trimen, Med. Plants, 169.

Botanical Source.—Styrax Benzoin is a tree from 50 to 70 feet high, with round, tomentose branches. The leaves are alternate, petiolate, oblong, entire, acuminate, smooth above, tomentose beneath, a palm long; the petioles are round, striated, tomentose, very short, and channeled. The flowers are on one side, in compound, axillary racemes, nearly the length of the leaves; the common foot-stalks are tomentose; the partial alternate, spreading and tomentose. The calyx campanulate, very obscurely 5-toothed; outwardly tomentose; above a line in depth. The petals, numbering 5, are linear, obtuse, outwardly gray with very fine down, and four times longer than the calyx. Stamens 10; filaments inserted into the receptacle, rather shorter than the petals, beneath connate into a cylinder of the length of the calyx, and ciliated on the upper part below the anthers. The anthers are linear and longitudinally adnate to the petals. The ovary is superior, ovate and tomentose; the style filiform and longer than the stamens. The fruit is a globose drupe, containing 1 or 2 nuts, angular, concave on one side and convex on the other (L.).

History.—This beautiful tree presents a handsome appearance with its conspicuous crown of large spreading branches, bearing deep-green leaves, hoary white on the under surface. Its flowers are either white or reddish. The tree is indigenous to Sumatra (where it is cultivated), Java, and Borneo. A kind of gum is also produced in Siam and Cochin China, while along the east bank of the Mekong, it is said to be produced from the neighboring cassia forests. The botanical name of the tree, which is the source of the Siam gum, is unknown. The greater portion of the commercial benzoin is collected in the northern and eastern portions of Sumatra, and comes into English markets as Gum Benjamin, the tree from which it is derived being known as the Benjamin, or Benzoin, tree. This resinous balsam is obtained by making incisions into the bark of trees 6 or 7 years old, from which the balsam flows in the form of a thick, milky, resinous juice, which is allowed to remain until sufficiently hardened, when it is collected and new incisions made. The trees yield about 3 pounds of resin annually for a period of about a dozen years. The first 3 years' yield gives a superior product, containing a greater quantity of white tears, and is designated by the natives as Head benzoin. A browner resin, inferior to the above, which exudes during the remaining 7 or 8 years, is known as Belly benzoin. The least valuable product, Foot benzoin, is that obtained by cutting down the tree, splitting the wood and scraping it. In this way it becomes mixed with foreign matter, such as wood, bark, etc. Benzoin appears in commerce in the form of square masses, having been melted by sun heat or hot water and poured into square receptacles. While the resin is known to the Malays by the above names (which correspond. to superior, medium, and inferior) it is known in commerce as two varieties—Siam benzoin and Sumatra benzoin.

Description.—Benzoin occurs in market in several grades, as regards the amount of milky-white tears contained in the mass. The Siam gum is regarded the most valuable, containing less foreign impurities than the Sumatra variety, the inferior grades of which are sometimes bark and but little resin.

SIAM BENZOIN comes in the form of square blocks having opaque, milky tears, often an inch or two in length, loosely adherent to each other. Usually, however, the tears are smaller, the mass more compact, the tears being imbedded in an amber-colored, or brown, resiniform material. Specimens containing the translucent resinous matter and very small tears, in appearance, are said to resemble Scotch granite. The tears show internally a semi-translucent, lamellated structure. Even the opaque tears become discolored and translucent by age. The resin is brittle, but may be readily softened by mastication, and has a pleasant fragrance, resembling that of the vanilla-bean. When heated benzoic acid is evolved.

SUMATRA BENZOIN also comes in rectangular blocks, usually having its tears imbedded in a grayish-brown resinous mass, intermixed with foreign matter. Its odor is not so pronounced nor as agreeable as that of the Siam product. A variety of Sumatra benzoin, of unknown origin, known as Penang benzoin (Benjamin), or Storax smelling benzoin (Benjamin) has a much more agreeable odor than the Siam variety, comparing somewhat with storax. It frequently consists of large tears, agglutinated together by a grayish resin. The fragrance of the different kinds of benzoin is best compared by adding water to their tinctures. The best variety (Siam) yields a reddish tincture, that of the other grades being yellow-brown or brown.

Benzoin is firm, brittle, pulverizable, of an agreeable, balsamic odor when rubbed, and of a sweetish, balsamic, somewhat acrid taste. When pure it is wholly soluble in alcohol or ether. Upon exposure to heat, benzoin consumes with the discharge of a dense, irritating, white smoke, consisting of benzoic acid and a fragrant empyreumatic oil. In pulverizing benzoin, it irritates the lining membrane of the nostrils, causing sternutation. Water added to its alcoholic solution, precipitates it, forming a white liquid, which has been used as a cosmetic under the name of virgin's milk. Benzoin has a specific gravity of about 1.068. Official benzoin is thus described in the U. S. P.: "In lumps consisting of agglutinated, yellowish-brown tears, which are internally milk-white, or in the form of a reddish-brown mass, more or less mottled, from whitish tears imbedded in it. It is almost wholly soluble in 5 parts of, moderately warm alcohol, and in solutions of fixed alkalies. When heated, it gives off fumes of benzoic acid. It has an agreeable, balsamic odor, and a slight, aromatic taste"—(U. S. P.).

That benzoin does not lose its properties by keeping is evident from the fact that the best benzoin we have ever seen was that recently recovered from a vessel wrecked in the East Indian trade two centuries ago.

Chemical Composition.—Benzoin belongs to the class of substances known as balsam-resins. It contains a small amount of volatile oil, about 75 per cent of amorphous resins, and about 18 per cent of benzoic acid. The white tears contain the latter in smaller quantities than the resiniform substance in which they are imbedded. Among the empyreumatic products resulting from the dry distillation of benzoin is a strongly fragrant, oily substance, designated styrol. Cinnamic acid (C₉H₉O₂) was found to be present in Siam and Penang benzoin (Kolbe and Lautemann, 1860). Sometimes only this acid is present, to the exclusion of benzoic acid. Aschoff found cinnamic acid alone in a sample of the Sumatra product, while in the amygdaloid Penang and Siam varieties, only the benzoic acid was present (1861). Flückiger, however, obtained cinnamic acid from the latter variety. Rump believed that both acids were not simultaneously present in any variety of benzoin, but that the cinnamic acid was present only in the Penang benzoin. The resins of benzoin, at least four in number, are all soluble in alcohol and caustic potash, but behave differently with other solvents, especially with ether. Vanillin, a product found mainly in vanilla, was obtained from Siam benzoin by Rump, in 1878. Benzoin was acted upon with caustic lime, the benzoic acid precipitated with chlorhydric acid, and, the remaining liquid agitated with ether and evaporated, when a mixture of vanillin and benzoic acid remained.

Action, Medical Uses, and Dosage.—The effects of benzoin are much the same as those of benzoic acid, which is its most abundant constituent, modified by the resin and essential oil. It is never given in bulk or alone. It is eliminated chiefly by the mucous membranes.

Benzoin exerts a stimulating influence on the mucous tissues, and has been used to promote expectoration in chronic diseases of the air-passages. It is also stated to stimulate the sexual organs. It enters into the manufacture of elixir of paregoric, and constitutes the basis of Turlington's and many other balsams, which exert a salutary influence in healing wounds; the tincture is also employed to form a coating over the adhesive preparations so well known as Court Plaster. The fumes or vapor inhaled into the lungs, has been strongly recommended in chronic pulmonary catarrhs, and old laryngeal inflammations. The tincture is protective and stimulant. in. the early stage of coryza and as a dressing for fresh wounds. Benzoin is principally used to prepare benzoic acid, to improve the taste and odor of other medicines, and in perfumery. The dose, in preparations, may be equivalent to 10 to 40 grains.

Related Products.—PAGLIARI'S STYPTIC. A preparation called Pagliari's Haemostatic or Styptic, has been used with some degree of success in hemorrhages. It is made by boiling together for 6 hours in a glazed earthen vessel, alum 1 pound, tincture of benzoin 8 ounces, water 10 pounds. As the water evaporates it must constantly be replaced with hot water, so as not to interrupt the ebullition, the resinous mass being stirred constantly. Then filter the fluid and keep in stoppered bottles. It is limpid, color of champagne, styptic in taste, and aromatic in odor. White resin has been successfully substituted for the benzoin. Every drop of this fluid poured into a glass containing human blood produces an instantaneous magma; and by increasing the proportion of the styptic to the quantity of the blood, a dense homogeneous, blackish mass results. It is said to be useful in all arterial and venous hemorrhages. In applying it, lint and bandages should be used to prevent the coagula which form from being removed from the mouths of the vessels; an application of them for 24 or 48 hours is sufficient.

King's American Dispensatory, 1898, was written by Harvey Wickes Felter, M.D., and John Uri Lloyd, Phr. M., Ph. D.