Zea (U. S. P.)—Zea.
The styles and stigmas of Zea Mays, Linné"—(U. S. P.).
COMMON NAME: Corn-silk.
Botanical Source.—Indian corn is a monoecious, paniceous grass, annual, with a fibrous root, and an erect, leafy stem, channelled on one side, 5 to 10, and, in some varieties, 15 to 20 feet high. The male flowers are terminal and racemose; the female axillary and densely spiked. Stamens 3. Ovary sessile and ovate. Style 1, long and capillary. Stigma ciliated. Caryopsides roundish or reniform, arranged on a large cylindrical receptacle or rachis, popularly called the cob, generally in 8 rows. The ordinary color of the ripe grains or caryopsides is yellow, but they are frequently met with white, parti-colored, red, purple, or even black (W.—P.).
History.—Corn is a native of the warm latitudes of America, and its varieties are exceedingly numerous. It is extensively cultivated in the United States, and also in various parts of the world, and is much used in these countries as one of the principal articles of diet. It is very nourishing and digestible, and is used in many forms in this country, as bread, mush, puddings, cakes, etc. It is incapable of being made into light or raised bread, on account of its small quantity of gluten. Roasting-ears, or hot corn, as it is called in this country, consists of the young ears, which are gathered just previous to becoming ripe and hard, and boiled in water. They form an agreeable and nutritious food, but should not be used by those disposed to looseness or other intestinal derangements. The parts used in medicine are corn-meal and the styles and stigmas, the latter two constituting the official Zea, which is thus described:
Description.—Zea, or Stigmata maydis, is "thread-like, about 15 Cm. (6 inches) long, and 0.5 Mm. (1/50 inch) broad, yellowish or greenish, soft-silky, finely hairy, and delicately veined longitudinally; inodorous; taste sweetish"—(U. S. P.).
Chemical Composition.—GRAIN OF MAIZE contains moisture (13.3 per cent), starch (50 to 67 per cent, and more), nitrogenous matters (about 10 per cent), fatty or oily substance (3.8 to 9 per cent), and mineral matters (about 1.5 per cent), consisting chiefly of potassium phosphate. The oil of maize occurs mainly in the embryo, and can not be obtained from the corn by mere pressure. The grains are allowed to sprout to a certain extent; the germ containing over 15 per cent of the oil, is separated by machinery from the starchy part, and is then softened by steam and subjected to hydraulic pressure, which separates the oil and yields a press-cake, rich in albuminoids, and retaining 4 to 5 per cent of oil. Or, the oil is yielded as a by-product in the manufacture of corn-starch (see J. M. Maisch, Amer. Jour. Pharm., 1885, p. 404, and J. U. Lloyd, ibid., 1888, p. 325; also see C. E. Bowers, ibid., 1889, p. 503). Oil of maize has been used as a lubricant, and in the manufacture of soap. It is a bland, non-drying, yellowish oil, having a specific gravity of. 0.92. It is readily saponifiable, and does not easily become rancid upon exposure to the air. Prof. Lloyd recommends its use especially in the making of ammonia liniment.
CORN-SILK (Zea).—C. J. Rademaker and John L. Fischer (Amer. Jour. Pharm., 1886, p. 369) found corn-silk to contain 5.25 per cent of a light-yellow fixed oil, resin, a crystallizable acid (maizenic acid of Vautier), soluble in water, ether, and alcohol, insoluble in petroleum spirit; and sugar, gum, albuminoids, etc. No volatile oil could be found. J. M. Hillan (ibid., 1884, p. 571), by distillation with alkali, obtained a basic distillate, yielding a crystalline acetate, which formed precipitates with solution of iodine and with Mayer's solution. The same author found 83.3 per cent of moisture, and in the dried corn-silk 12.5 per cent of ash. Sugar was observed in green but not in the dried corn-silk. (For pharmaceutical preparations from corn-silk, see Geo. W. Kennedy, Amer. Jour. Pharm., 1883, p. 242.)
Action, Medical Uses, and Dosage.—Corn-silk is diuretic and slightly anodyne, and, for the former purpose, has been found useful in many urinary troubles, associated with renal and cardiac disorders. In southern France, the inhabitants use it as a domestic remedy for calculi, gravel, and strangury. It has been found of value by physicians in the treatment of cystic irritation, due to phosphatic and uric acid concretions, and in both acute and chronic inflammations of the bladder, whether traumatic or idiopathic. Dropsy, when due to cardiac or renal origin, and particularly after such urinary disorders as those above mentioned, and pyelitis, catarrh of the bladder, and urinal retention appear to be benefited by the diuretic action of this drug, which action is said to be quite positive. Besides its diuretic effects, the drug seems to be a cardiac stimulant as well. In fact, its diuretic action is largely due to its tonic action upon the heart and blood vessels. It is especially of value in the bladder disorders of children, in gonorrhoea, and in cases where decomposition of the urine is prone to take place within the bladder. The active virtues are attributed to the maizenic acid, which may be given in ⅛-grain doses. However, the infusion of the fresh "silk" (silk ℥ii to boiling water Oj) is the most active preparation, and should be freely administered. The fluid extract, which is said to well represent the drug, may be given in doses of ½ to 2 fluid drachms, every 2 to 4 hours.
CORN-MEAL forms a very palatable and nutritious gruel for the sick, and, in the form of mush, is an excellent diet for convalescents, as well as a good emollient poultice for ulcers, swellings, rheumatic pains, etc. An infusion of parched corn is useful in allaying the nausea and vomiting attendant upon many diseases. It may be drank freely. (For the parasitic fungus growing on corn [Ustilago Maydis], see Ustilago.)