Red rose petals (Rosa Gallica, U.S.P., Red Rose) are obtained from the red or Provence rose, Rosa gallica, Linn. (N.O. Rosaceae), which is cultivated generally throughout Europe. The unexpanded petals are plucked as a whole from the calyx, and the lighter-coloured basal portions cut off. They are used both fresh and dried; in the latter case being gently sifted to remove any Stamens. The petals generally occur in little conical masses, easily separated into the individual petals, which are obcordate in shape, velvety, and of a deep purplish-red colour. They possess a delicate, rose-like aroma, and a slightly astringent taste. The petals yield about 4 per cent. of ash.
Constituents.—The colour of the drug appears to be due to an amorphous, deep red substance, soluble in water and in alcohol. It also contains a yellow, crystalline body, similar to, but not identical with, quercitrin, together with gallic acid, and possibly quercitannic acid. The colour of an aqueous infusion, like that of the red colouring matter, is deepened by the addition of sulphuric acid, and turned green by alkalies.
Action and Uses.—Red rose petals are mildly astringent. For this property and for their colouring matter they are used as Infusum Rosae Acidum, and as Syrupus Rosae. Acid infusion of roses is a convenient vehicle for gargles containing alum or tannin; it should not be prescribed with borax or other alkaline salts. It is used also as a vehicle for quinine in mixture form. Red rose petals are further employed in the preparation of the confection and liquid extract of, rose. The latter is a useful colouring agent for acid and neutral mixtures. So-called "Liquor Rosae Dulcis" is usually prepared from cochineal.
- Confectio Rosae, U.S.P.—CONFECTION OF ROSE.
- Red rose, in No. 60 powder, 8; sugar, in fine powder, 64; clarified honey, 12; rose water, undiluted, 16.
- Confectio Rosae Gallicae, B.P.—CONFECTION OF ROSES.
- Fresh red rose petals, 25; refined sugar, 75. Add the rose petals to the sugar and beat well together in a stone mortar. Confection of roses is used chiefly as a pill excipient.
- Extractum Rosae Liquidum, B.P.C.—LIQUID EXTRACT OF ROSE. 1 in 1.
- Liquid extract of rose is a suitable colouring agent for acid mixtures, in the proportion of 1 mil (15 minims) to 30 mils (1 fluid ounce) of mixture. Alkalies change the fine red colour to a murky green.
- Fluidextractum Rosae, U.S.P.—FLUIDEXTRACT OF ROSE.
- Similar to B.P.C., but made with alcohol (49 per cent.) and without sulphuric acid.
- Infusum Rosae Acidum, B.P.—ACID INFUSION OF ROSES.
- Red rose petals, dried and broken, 2.5; diluted sulphuric acid 1.25; distilled water, boiling, 100. Infuse the petals in the acid and water for fifteen minutes, in a covered vessel, and strain. Acid infusion of roses is used generally as the basis of astringent gargles, especially with alum or tannin. It is not compatible with borax or alkalies, which change its colour to green. The infusion is sometimes prescribed with the sulphates of sodium and magnesium. Dose.—15 to 30 mils (1/2 to 1 fluid ounce).
- Infusum Rosae Acidum Concentratum, B.P.C.—CONCENTRATED ACID INFUSION OF ROSES.
- A product closely resembling acid infusion of roses is obtained by diluting 1 part of this preparation with 7 parts of distilled water. Dose.—2 to 4 mils (1/2 to 1 fluid drachm).
- Mel Rosae, U.S.P.—HONEY OF ROSE.
- Fluidextract of rose, 12; clarified honey, to 100. Average dose.—4 mils (1 fluid drachm).
- Syrupus Rosae B.P.—SYRUP OF ROSES.
- Dried red rose petals, 4; refined sugar, 60; distilled water, boiling, 40. Add the petals to the water, and allow them to infuse for two hours; then strain, press the residue, heat the strained infusion to boiling point, filter, add the sugar to the filtrate, and dissolve by the aid of heat. The resulting syrup should weigh 92. Syrup of roses is used as a colouring agent for mixtures and gargles. Dose.—2 to 4 mils (1/2 to 1 fluid drachm).
- Syrupus Rosae, U.S.P.—SYRUP OF ROSE.
- Fluidextract of rose, 12.5; diluted sulphuric acid (10 per cent.), 1; sugar, 75; water, sufficient to produce 100.
The British Pharmaceutical Codex, 1911, was published by direction of the Council of the Pharmaceutical Society of Great Britain.