Turkey CornBotanical Name: Dicentra Canadensis (D.C.)
Family: N.O. Furnariaceae
Synonyms: Turkey Pea. Squirrel Corn. Staggerweed. Bleeding Heart. Shone Corydalis. Corydalis. Corydalis Canadensis (Goldie). Bicuculla Canadensis (Millsp.).
Part Used: Dried tubers.
Habitat: Westward and south of New York to North Carolina.
Description: This plant is essentially indigenous to America, a perennial 6 to 10 inches high, with a tuberous root, flowering in early spring (often in March) having from six to nineteen nodding, greenish-white, purple-tinged flowers, the root or tuber small and round. It should be collected only when the plant is in flower. It grows in rich soil on hills and mountains. The tubers are tawny yellow-coloured, the colour being a distinctive character. The plant must not be confounded with Corydalis (Dicentra) Cuccularia (Dutchman's Breeches), which flowers at the same time and very much resembles it (though smaller), except in the root, the rind of which is black with a white inside, and when dried, turns brownish-yellow, and under the microscope is full of pores. It has also a peculiar faint odour, the taste at first slightly bitter, then followed by a penetrating taste, which influences the bowels and increases the saliva; the differences in the colour after drying may be caused by the age of the root. Under the microscope, it is porous, spongy, resinous, with a glistening fracture. Another Corydalis also somewhat like Turkey Corn is C. Formosa, the fresh root of which is darkish yellow throughout and has a fracture much resembling honeycomb. The true Turkey Corn is much used by American eclectic practitioners. It is slightly bitter in taste and almost odourless. Tannic acid and all vegetable astringents are incompatible with preparations containing Turkey Corn, or with its alkaloid, Corydalin.
Constituents: The amount of alkaloids in the dried tubers is about 5 per cent; they have been found to contain corydalin, fumaric acid, yellow bitter extractive, an acrid resin and starch. The constituents of the drug have not been exactly determined, but several species of the closely allied genus Corydalis have been carefully studied and C. tuberosa, cava and bulbosa have been found to yield the following alkaloids: Corycavine, Bulbocapnine and Corydine; Corydaline is a tertiary base, Corycavine is a difficult soluble base; Bulbocapnine is present in largest amount and was originally called Corydaline. Corydine is a strong base found in the mother liquor of Bulbocapnine and several amorphous unnamed bases have been found in it. All these alkaloids have narcotic action. Protopine, first isolated from opium, has been found in several species of Dicentra and in C. vernyim, ambigua and tuberosa.
Medicinal Action and Uses: Tonic, diuretic and alterative; useful in chroniccutaneous affections, syphilis and scrofula and in some menstrual complaints. The corydalin sold by druggists is often impure.
Turkey Corn is often combined with other remedies, such as Stillingia, Burdock or Prickly Ash.
Dosages: An infusion is prepared of 5 grams of the powdered Corydalin in 100 c.c. of hot distilled water stirred for 10 minutes and then filtered. This gives a light amber fluid and a precipitate with mercuric-potassium iodide T.S. and a dark blue colour with Iodine T.S.
Infusion, 1/2 OZ. in 1 pint of boiling water, in wineglassful doses three or four times daily. Fluid extract, 1/2 to 1 drachm. Corydalin, in 1/2 grains, three or four times daily. Saturated tincture, 1/2 drachm to 2 fluid drachms.
C. ambigua, used by the Chinese in medicine. A number of the same alkaloids are found in it and others closely allied.
As commonly understood in medicine, the name Corydalis applies to the tubers of Turkey Corn, but several others of the genus Dicentra and Corydalis are used.