"The dried petals of Rosa gallica Linné (Fam. Rosaceae), collected just before the expansion of the flower. Preserve Red Rose in tightly-closed containers, protected from the light." U. S. "Red-Rose Petals are the fresh or dried unexpanded petals of Rosa gallica, Linn.; obtained from cultivated plants." Br.
Rosae Gallicae Petala, Br., Red-rose Petals; Flores Rosarum Rubrarum; Rose rouge ou Rose de Provins, Fr. Cod.; Roses rouges, Fr.; Sammtrose, Zuckerrose, Französische Rose, Essigrosenblätter, G.; Rosa rossa, It.; Rosa roja (Flore de), Rosa rubra, Sp.
At one time pale rose or Rosa centifolia was official in addition to red rose or Rosa gallica. There is no uniformity on the subject in the several Pharmacopoeias. The Pharmacopoeia of the Netherlands and the French Codex still include both species. The German Pharmacopoeia, on the other hand, specifies only the petals of Rosa centifolia. The British and Austrian Pharmacopoeias are in unison with the U. S. Pharmacopoeia in restricting the drug to R. gallica.
Rosa gallica is smaller than R. centifolia L., but resembles it in the character of its foliage. The stem is beset with short bristly prickles. The flowers are very large, with obcordate widely spreading petals, which are of a rich crimson color, and less numerous than in the R. centifolia. The stamens on thread-like filaments, and the villose styles bearing papillary stigmas, are numerous. The fruit is oval, shining, and of a firm consistence. The red rose is a native of the south of Europe, and is cultivated in gardens throughout the United Scales.
The drug is officially described as "petals either separate or imbricated in small cones, broadly ovate, summit rounded and deeply notched, margin entire and somewhat recurved, base obtuse; externally of a purplish-red color except the light-brown claw; texture velvety; when dry, brittle; odor agreeable; taste astringent and slightly bitter. Under the microscope, transverse sections of the petals of Red Rose show the upper epidermal cells modified to conical papillae and containing a purplish-red cell sap; a loose mesophyll composed of from 2 to 10 rows of cells among which are the fibro-vascular bundles with spiral tracheae, and a lower epidermis of rectangular cells filled with a purple cell sap. Red Rose yields not more than 3.5 per cent. of ash." U. S.
"Usually in little cone-like masses, or sometimes separate and more or less crumpled. Petals velvety, deep purplish-red passing into brownish-yellow towards the base. Fragrant odor; taste slightly astringent." Br.
The petals should be gathered before the flower has blown, separated from their claws, dried in a warm sun or by the fire, and kept in a dry place. Their odor, which is less fragrant than that of R. centifolia, is improved by drying. They have a velvety appearance, a purplish-red color, and a pleasantly astringent and bitterish taste.
An illustrated article on the structural characteristics of rose petals, whole and powdered, has been published by Hans Kramer in B. P. G., 1907, xvii, p. 354.
Their constituents, according to Cartier, are tannin, gallic acid, coloring matter, a volatile oil, a fixed oil, albumen, soluble salts of potassium, insoluble salts of lime, silica, and ferric oxide. (J. P. C., vii, 531.) According to Filhol, the astringency of red roses is ascribable less to tannic acid, of which they contain but a trace, than to quercitrin, which he obtained in notable proportion, and with which their color is probably connected. Rochleder found that in red roses the gallic acid is accompanied by quercitannic acid. They also contain much uncrystallizable sugar. (Repert de Pharm., Mai, 1863.) The sensible properties and medicinal virtues of the flowers are extracted by boiling water. Their coloring matter, according to Senior (Y. B. P., 1877, p. 63), is an acid, which appears to form crystallizable salts with potassium and sodium, and amorphous ones with the heavy metals. Senior gives as the formula of the insoluble lead compound Pb2C21H29O30. Their infusion is of a pale reddish color, becoming bright red on the addition of sulphuric acid. As their color is impaired by exposure to light and air, they should be kept in opaque well-closed bottles or canisters.
Uses.—Red rose is slightly astringent and tonic, and it was formerly thought to possess peculiar virtues. It it at present chiefly employed as affording an elegant vehicle for tonic and astringent medicines.
The Dispensatory of the United States of America, 1918, was edited by Joseph P. Remington, Horatio C. Wood and others.