Preparation: Mucilage of Salep
The dried tubers of several species of Orchis and related genera.
Botanical Source and History.—Formerly, the tubers derived from Eulophia campestris and E. herbacea, Lindley, and related species, growing in Persia and the Levant, constituted the drug salep. South and central Europe now furnish salep, and the only kinds admitted in the German Pharmacopoeia are those unbranched tubers derived from Orchis mascula, Linné; Orchis ustulata, Linné; Orchis Morio, Linné; Platanthera bifolia, Reichenbach; Anacamptis pyramidalis, Richard;and other related species. The tubers are gathered, scalded, and dried quickly, which process removes their bitterness and disagreeable odor, as well as renders them somewhat translucent. The Oriental salep is less translucent than that from Europe. Oriental salep is dark in color. Among other species, the Orchis masculata, Linné; Orchis latifolia, Linné; Orchis sambucina, Linné;and Gymnadaenia conopsea, Robert Brown, furnish the flattish, palmately-divided tubers, having 3 to 5 divisions. They resemble the commercial grades, excepting that they contain less mucilage. They were once called Radix Palmae Christi.
Description and Chemical Composition.—European salep is never so large as Oriental salep, which ranges from 1 to 1 3/5 inches in length, ovoid, oval, oblong, or pyriform, more or less flattened and corrugated, and marked at the apex with a terminal bud-scar. It is yellowish and translucent, hard, and horn-like, and without odor, but has a mucilaginous and somewhat insipid taste. In commerce it occurs mostly as a yellowish powder. The chief constituents of salep, according to Dragendorff (1865), are mucilage (48 per cent), starch (27 per cent), albuminous bodies (5 per cent), etc. The mucilage of salep is soluble in cold water, this solution being precipitated by alcohol, and by basic lead acetate.
Action, Medical Uses, and Dosage.—Salep is nutrient and demulcent. Administered in milk, water, broth, or jelly, it is useful in the summer diarrhoeas of infants and children, and in the chronic diarrhoea of adults, particularly that form associated with tuberculosis. A good mucilage may be prepared by macerating 40 grains of salep in some cold water, and subsequently adding boiling water until 8 fluid ounces of water have been used. The jelly may be prepared by rubbing 30 grains of salep with water until the powder has swollen fourfold, and gradually adding, with continual stirring, 8 fluid ounces of boiling water; boil until but 4 ounces remain. Like tapioca and similar products, it may be freely administered.