Taraxacum (U. S. P.)—Taraxacum.
"The root of Taraxacum officinale, Weber, gathered in autumn"—(U. S. P.) (Leontodon taraxacum, Linné; Taraxacum Dens-leonis, Desfontaines; Taraxacum vulgare, Schrank).
COMMON NAMES AND SYNONYM: Dandelion, Dandelion root; Taraxaci radix.
ILLUSTRATION: Bentley and Trimen, Med. Plants, 159.
Botanical Source.—This plant is an herb with a perennial, tap-shaped, very milky root, with a dull-brownish epidermis. The leaves are radical, numerous, spreading, of a bright, shining green, quite smooth, tapering downward, sessile, pinnatifid, with runcinate, sharp, unequally toothed lobes. The scape or flower-stem is longer than the leaves, erect, round, smooth, brittle, naked, hollow, 5 or 6 inches in height, and bears a single, yellow head. The flowers are of a uniform golden-yellow, in round heads, 1 1/2 inches in diameter, expanding in the morning and fine weather only. Involucre double; external scales small, closely pressed, and spreading or reflexed; internal ones in one row, erect, and linear; all frequently callous-horned at the apex. Florets numerous, strap-shaped, equal, and 5-toothed. Stamens with hair-like filaments. Receptacle naked, convex, and dotted. Ovary obovate; style slender and cylindrical; stigmas 2, revolute. Achenia oblong, ribbed, roughened on the ribs, apex prolonged into a very slender, thread-like beak, bearing the pappus of copious, soft, and white capillary bristles. After blossoming the inner involucre closes for a time, the slender beak elongates and raises up the pappus while the fruit is forming, the whole involucre is then reflexed, exposing to the wind the naked fruits, with the pappus displayed in an open globular head, nearly 2 inches in diameter (L.—G.—W.).
History and Description.—This plant is a native of Greece, but is now found growing abundantly in Europe and this country, in fields, gardens, and along roadsides, flowering from April to November. There are some other species recognized by botanists, that appear to possess the same medicinal powers. The young leaves are frequently used as a salad or greens. The whole plant, when broken or wounded, exudes a white, bitter juice, the sensible qualities of which are said to be greater during period of inflorescence. The root only is the official part, and should be collected while the plant is in flower, or preferably in autumn. When recent, it is from 3 to 5 inches or more in length, from 3 to 9 lines in diameter, tap-shaped, fleshy, dull-yellow or brownish externally, white internally, inodorous, and bitter. As found dried in pharmacy, it is considerably diminished in size, having lost more than half its weight, and corrugated lengthwise. As required by the U. S. P., it is slightly conical, about 30 Cm. (12 inches) long, and 1 or 2 Cm. (2/5 to 4/5 inch) thick above, crowned with several short, thickish heads, somewhat branched, dark-brown, longitudinally wrinkled, when dry breaking with a short fracture, showing a yellowish, porous central axis, surrounded by a thick, white bark, containing numerous milk-vessels, arranged in concentric circles; inodorous, bitter. It should be free from the root of Cichorium Intybus, Linné (Nat. Ord.—Compositae), which closely resembles it, but is usually paler, and has the milk-vessels in radiating lines"—(U. S. P.). Dandelion root should preferably be used in the recent state. Drying, as well as long boiling, impairs its virtues. Alcohol or boiling water extracts its properties.
Chemical Composition.—Taraxacum root contains inulin, the quantities of which vary considerably with the season. Dragendorff (1870) found 24 per cent in root collected in October, and only 1.74 per cent in root collected in March, shortly before blooming, at which season the milky juice is abundant. The root also contains variable quantities of reducing sugar (17 per cent in March), and laevulin (18.7 per cent). (See constituents at various seasons, by L. E. Savre, in Proc. Amer. Pharm. Assoc., 1893, p. 82; also paper, by Charles Symes, in Pharm. Jour. Trans., Vol. X, 1872, p. 361.) Other constituents of taraxacum root are a resin, soluble in chloroform and ether, insoluble in alcohol; a resin soluble in alcohol; taraxacerin of Kromayer (1861), a white waxy substance, crystallizing in cauliflower-like formations, and taraxacin (Polex, 1839), a bitter, amorphous principle, which, in concentrated solutions, forms precipitates with a number of alkaloidal reagents. Kromayer obtained these two principles from the inspissated milky juice of the root (leontodonium) by treating it with hot water. This leaves taraxacerin undissolved, which may then be obtained pure by recrystallization from hot alcohol. Prof. Sayre (Proc. Amer. Pharm. Assoc., 1897, p. 223) assigns to it the formula C9H15O. The aqueous extract of leontodonium contains the bitter principle; this is abstracted by charcoal, and the latter boiled out with alcohol. The latter is distilled off, the residue dissolved in water, precipitated by means of basic lead acetate, the lead removed from the filtrate by hydrogen sulphide, and the solution evaporated to dryness, and an acrid resin removed by ether. The residue is bitter taraxacin. (For a bibliography of taraxacum, see L. E. Sayre, Proc. Amer. Pharm. Assoc., 1876, p. 16-5.) A. van Zwaluwenburg and M. Gomberg (Proc. Amer. Pharm. Assoc., 1899, p. 305) also observed the presence of minute quantities of a substance giving alkaloidal reactions; however, the authors doubt its alkaloidal nature. Other constituents of taraxacum root, at least of partly fermented extracts, are calcium lactate and mannite. The leaves and stems, according to Marmé (1864), contain the sugar inosite. The incinerated root leaves 5 to 7 percent of ash.
Action, Medical Uses, and Dosage.—Dandelion root, when dried, possesses but little medicinal virtue; when recent, it is a stomachic and tonic, with slightly diuretic and aperient actions. It has long been supposed to exert an influence upon the biliary organs, removing torpor and engorgement of the liver as well as of the spleen. It is also reputed beneficial in dropsies, owing to want of action of the abdominal organs, in uterine obstructions, chronic diseases of the skin, and impairment of the digestive functions. It should not be used by those whose digestive organs are weak, as it is apt to occasion dyspepsia, flatulence, pain, and diarrhoea. The addition of cream of tartar to its decoction will render it more diuretic and laxative. Prof. King states that, as far as his experience with this article had gone, he thought its virtues had been overrated. Nevertheless, it is a slow, but efficient agent when properly prepared for use. The existence of an irritable condition of the stomach or bowels, or acute inflammation, contraindicate its employment. Dose of the decoction, 1 to 2 fluid ounces; of the extract, from 5 to 30 grains; of a strong tincture of the fresh root (℥viii to alcohol, 76 per cent, Oj), from 1 to 30 drops.
Specific Indications and Uses.—Loss of appetite, weak digestion, hepatic torpor, and constipation.
King's American Dispensatory, 1898, was written by Harvey Wickes Felter, M.D., and John Uri Lloyd, Phr. M., Ph. D.