Frasera. American Colombo. Frasera carolinensis.
Frasera. Radix Fraserae. Radix Colombo Americana; Racine de Colombo de Mariette (d' Amerique), Fr. Frazerawumel, Amerikanische Colombowurzel, G.—American Columbo is yielded by Frasera carolinensis Walt. (Fam. Gentianaceae), a perennial herb which nourishes in rich dry soil from New York and Wisconsin southward. The period of flowering is from May to July; but the stems and flowers are produced only in the third year, the radical leaves being the only part of the plant which previously appears above ground. From this manner of growth, it is inferred that the roots, which were formerly included in the Secondary List U. S. P., should be collected in the autumn of the second or the spring of the third year. Before being dried, they should be cut into transverse slices.
As formerly in the market, frasera was in disc-like pieces resembling calumba, but are easily distinguishable by the greater uniformity of their internal structure, the absence of concentric and radiating lines, and their purer yellow color, without a greenish tinge. The root sliced longitudinally, so as to imitate gentian, has been offered in the market as American gentian. The taste of frasera is bitterish and sweetish. Water and diluted alcohol extract its virtues, and the tincture precipitates upon the addition of water, but is not affected by tincture of galls. The hot infusion is not precipitated by solution of gelatin, and gives with iodine no signs of starch. These reactions afford additional means of distinguishing the root from calumba. It contains gum, pectin, glucose, wax, resin, fatty matter, yellow coloring matter, bitter extractive, and an acid which is probably peculiar. (A. J. P., Jan., 1862, 23.)
Frasera is a feeble, simple bitter. Dose, of powder, one drachm (3.9 Gm.); of infusion (1 fl. oz. to 1 pint boiling water), two fluidounces (60 mils) a day. The fresh root is said to be emetic and cathartic.