Licorice USD 1926
Compiled By Ivor Hughes

GLYCYRRHIZA Glycyrrh. (Licorice Root)
Glycyrrhiza is the dried rhizome and roots of Glycyrrhiza glabra Linne var. typica Regel et Herder, known in commerce as Spanish Licorice or of Glycyrrhiza glabra Linne var. glandulifera Regel et Herder known in commerce as Russian Licorice, or of other varieties of Glycyrrhiza glabra Linne yielding a yellow and sweet wood (Fam. Leguminosae). Glycyrrhiza yields not more than 2.5 % of acid insoluble ash.

Liquorice Root is the peeled root and peeled subterranean stem of Glycyrrhiza glabra Linn., and other species of Glycyrrhiza." Br.

Glycyrrhizae Radix, Br.; Radix Glycyrrhizae Hispanicae Spanish Licorice Root; Liquiritiae Radix,

Reglisse, Fr. Cod.; Reglisse, Racine do Reglisse, Bois doux, Racine douce, Fr.; Radix Liquiritiae P. C.: Spanisches Sussholz, Spanische Sussholzwurzel, Sussholzwurzel, G.; Liquirizia It.; Regalia (Raiz de), Orozuz, Palo dulce, Sp.

Glycyrrhiza glabra, which yields Spanish Licorice, is a perennial herb whose underground portion consists of a slender branching rhizome bearing a number of delicate rootlets. The stems are herbaceous, erect, slightly branching, and usually four or five feet in height.

The leaves are alternate, pinnate, consisting of several pairs of ovate, blunt, petiolate leaflets, with a single leaflet at the end, of a pale-green color, and clammy on their under surface.

The flowers are violet or purple, formed like those of the pea, and arranged in axillary spikes supported on long peduncles The calyx is tubular and persistent.

The fruit is a compressed, smooth, acute, one-celled legume, containing from one to six small kidney-shaped seeds. This plant grows best on sandy soil near streams, usually not being found more than fifty meters from a body of water.

It is indigenous to southern Europe and southwestern Asia, and is cultivated in England, Germany, Spain, Italy and Austria and has been grown on an experimental scale in the United States.

Glycyrrhiza echinata, the source of "Russian Licorice," is a native of southern Russia and Hungary but also occurs in the wild state in Italy, Sicily and other Mediterranean countries where it is also cultivated.

Its subterranean portion consists of a fleshy, fusiform root, from which stems spring that attain a height of 5 to 6 feet. These are several branched, the branches being cylindrical toward the base and angled toward their ends.

The leaves are smooth, imparipinnate, with oblongmucronate leaflets. The flowers are violet colored and occur in short-stalked, axillary heads in the leaf axils. The fruit is an oval, pointed, spiny, one-seeded legume.

A comparatively small portion of the licorice imported into the United States is used by the drug industry, the greater bulk of the huge supply which is annually coming into our ports being consumed by the tobacco and confectionery trades and in fire extinguisher compounds. The root is collected alike from wild and cultivated plants, cleaned and variously prepared for the market.

The Spanish variety is the most esteemed and usually comes in segments of variable length, in bundles, and as cut root, the first two grades being packed in covered or uncovered bales, the last, in bags. This variety has been frequently named after the country in which it is collected, a practice which has often been confusing to the purchaser.

Most of the licorice designated as Italian, Turkish, Levant, Persian or Arabian has been found to be yielded by geographical varieties of G. glabra It is shipped commonly from Smyrna, Haifa, the Spanish ports of Alicante, Barcelona and Seville, from Leghorn, Italy, Constantinople and Marseilles.

Russian Licorice is now being shipped chiefly through Hamburg and London to the United States. Importations of this variety have been comparatively small. It occurs an the market both in the peeled and unpeeled condition, the peeled roots often being split lengthwise. Licorice is often offered for entry that is poorly dried, mouldy, insect infested or partially decayed; such roots should he rejected.

According to Rusby (Ph. Era, 1909, p. 634), ground licorice has been imported which apparently consisted of the peelings of Russian licorice. Asiatic licorice, known as "Chuntschir," is obtained from G, uralensis Fisch. The plant is found in Siberia, Turkistan and Mongolia, and it is claimed that the root is of better quality and is but little inferior if any to the best Russian licorice. (See Alsberg and Vichoever, J. A. Ph. A., 1919, viii, 467 and also P. J., 1905, lxxxi, 1G4.)

The U.S. Department of Agriculture has had Spanish licorice under cultivation in South Carolina and the plant thrives in various localities in this country. It is said that the soil and climatic conditions in the Coachella Valley of California are ideal for the growing of the licorice plant.

A species of Glycyrrhiza, G. lepidota Pursh., grows abundantly from Missouri, westward into Nevada and northern California and northward to Washington. It is probably the same as the licorice plant mentioned by Mackenzie as growing on the northern coast of this continent. Nuttall states that its root possesses in no inconsiderable degree the taste of licorice, and M. L. McCullough found it to contain 6.39 per cent. of crude glycyrrhizin, in contrast with 7.18 per cent. in the official species. (A. J. P., 1890.) Schneider reports that G. lepidota glutinosa Pursh., a native of California, is much like G. glabra and can no doubt be substituted for the true licorice. (Pacific Pharm., ii, p. 144.)

Description and Physical Properties. Unground Spanish Licorice. - Nearly cylindrical, the upper portion more or less knotty; usually in pieces from 14 to 20 cm. or more in length and from 5 to 20 mm. in thickness; externally yellowish-brown or dark brown, longitudinally wrinkled, the thinner rhizomes often having prominent alternate buds, the thicker rhizomes having distinct corky patches; fracture coarsely fibrous; internally yellow, radiate; odor distinctive; taste sweetish and slightly acrid.

Unground Russian Licorice .- Nearly cylindrical, somewhat tapering, sometimes split longitudinally, from 15 to 30 cm. in length and from 1 to 5 cm. in diameter; when deprived of the outer corky layer, it is externally pale yellow; fracture coarsely fibrous; internally pale yellow; wood radially cleft; odor distinct; taste sweetish.

Structure - Rhizome with numerous layers of yellowish-brown. cork cells, absent in the peeled drug; one or more rows of cells with a tendency to collenchymatous thickening; a middle bark of starch-bearing parenchyma and groups of bast - fibers surrounded with crystal fibers;

Inner bark with radial arrangement of phloem and medullary rays, the phloem consisting of wedges of small groups of bast-fibers and parenchyma separated tangentially by sieve tissue, the cells of the latter with thick, highly refracting walls; medullary rays from 1 to 8 cells wide; wood bundles characterized by broad wedges consisting of large tracheae with yellowish walls, small compact groups of wood-fibers and starch-bearing parenchyma; pith of large, more or less polygonal starch-bearing parenchyma or occasionally containing prisms of calcium oxalate. In roots the pith is absent.

Powdered Glycyrrhiza. - Brownish - yellow (unpeeled Licorice) or pale yellow (peeled Licorice); starch grains numerous, mostly single and elliptical or oval, from 0.002 to 0.020 mm. in diameter; trachea mostly with bordered pores; wood- and bast-fibers numerous, very long, much attenuated at the ends and about 0.010 width; crystal-fibers with monoclinic prisms of calcium oxalate, the latter from 0.010 to 0.030 mm. in length; occasional fragments of reddish-brown cork cells which are practically absent in the powder prepared from peeled Licorice." U.S.

"When 5 grammes are macerated with 50 millilitres of chloroform water for twenty-four hours, shaken occasionally and filtered, 10 millilitres of the filtrate evaporated in a flat-bottomed dish yield not less than 0.200 gramme of residue dried at 100� C. Ash not more than 6 per cent." Br.

A character said by Rothrock (A. J. P., 1884) to be diagnostic of Glycyrrhiza is the occurrence of crystal fibers adjoining the wood and bast fibers. These are recognized in the official description of the powdered drug. In the Russian root the parenchymatous wood cells are larger than in the Spanish. The powder is of a grayish-yellow color, when the root is pulverized without being deprived of its epidermis; of a pale sulphur-yellow, when the epidermis has been removed.

Constituents. Besides various ordinary matter such as starch, lignin, etc., glycyrrhiza contains a brown acrid resin, a crystallizable substance originally called agedoite but now known to be asparagin, and a characteristic principle known as glycyrrhizin.

This is in reality the acid ammonium salt of glycyrrhizic acid, C44H62NO18NH4 It is a glucoside which, according to Kobert (Ph. Ztg., 1915, 182) belongs to the group of saponins and yields upon hydrolysis a hemolitic product; he also states that. there are present in the root other saponins.

Glycyrrhizic acid does not possess the characteristic sweetness of licorice, but its salts, especially the ammonium compounds, are sweet. Roussin in 1S75 showed that licorice root which has lost a portion of its sweetness through fermentation, could be restored by treating with ammonium and suggested the name of ammonium glycyrrhizate as proper for the sweetening principle.

Glycyrrhizic acid is practically insoluble in cold water and the method of precipitating it from infusions of licorice root by means of sulphuric acid has been used for the purpose of assaying licorice (see under Extraction Glycyrrhiza). Habermann (An. Ch. Ph., cxcvii) studied the properties of glycyrrhizic acid.

He found that it was insoluble in ether, slightly soluble in absolute alcohol but more soluble in alcohol of lower percentage. It was only sparingly soluble in water but formed with it a transparent yellowish jelly. Houseman who has done considerable work on glycyrrhiza (A. J. P:, 1916, lxxxviii, 97) states that the biologically active saponins of licorice are in the inner bark. He also confirms the nitrogen content of glycyrrhizin which had been questioned.

Under the name of Glycyrrhizinum Ammoniatum (Ammoniated Glycyrrhizin, Glyzina), the U. S. IX recognized a crude form of this substance which it defined as " A sweet principle combined with ammonia obtained from glycyrrhiza." U.S. II.

The process for making this preparation was given in the U. S. P. VIII as follows:

Glycyrrhiza, in No. 20 powder, five hundred grammes. Water, Ammonia Water, Sulphuric Acid, each, a sufficient quantity. Mix four hundred and seventy-five cc. of Water with twenty-five cc. of Ammonia Water, and, having moistened the powder with the mixture, macerate for twenty-four hours.

Then pack it moderately in a conical glass percolator, and gradually pour water upon it until five hundred cc. of percolate are obtained. Add Sulphuric Acid slowly to the percolate, with constant stirring, so long as a precipitate is produced.

Collect this on a strainer, wash it with cold Water until the washings no longer have an acid reaction, redissolve it in Water with the aid of Ammonia Water, filter, if necessary, and again add Sulphuric Acid so long as a precipitate is produced.

Collect this, wash it, dissolve it in a sufficient quantity of Ammonia Water previously diluted with an equal volume of Water, and spread the clear solution upon plates of glass, so that, when dry, the product may be obtained in scales." U. S. P. VIII.

The U. S. P. IX described it as follows:
Ammoniated Glycyrrhizin occurs in dark brown or brownish-red scales, without odor, and having a very sweet taste. It is freely soluble in water and soluble in alcohol. Its aqueous solution when heated with potassium hydroxide T.S. evolves ammonia.

Supersaturate an aqueous solution of Ammoniated Glvcyrrhizin with an acid; a precipitate is produced (consisting essentially of glycyrrhizin), which, when dissolved in hot water, forms a jelly on cooling. This substance, after being washed with diluted alcohol and dried, appears as an amorphous, yellow powder, having a strong, bitter-sweet taste, and an acid reaction. Incinerate 0.5 Gm. of Ammoniated Glycyrrhizin ; not more than 0.5 per cent. of ash remains." U.S. IX.

According to Habermann glycyrrhizin is decomposed, by boiling with diluted sulphuric acid, into glyeyrrhetin and parasaccharic acid, according to the reaction: C44H63NO18 + 2H2O = C32H47NO4 + 2C6H10O8. By fusing glycyrrhizin with potassium hydroxide, Weselsky and Benedikt (B. Chem. G., 1876) obtained paraoxybenzoic acid.

For methods of quantitatively determining glycyrrhizin, see Ext. Glycyrrh.

Uses. Powdered licorice root is used for various pharmaceutical purposes as in the preparation of pills, either to give due consistence or to cover their surface and prevent them from cohering, and as a diluent of powdered extracts, etc. As a remedial agent it has been almost entirely replaced by the extract.

Off. Prep. Extractum Glycyrrhizae, Br.; Extractum Glycyrrhizae Purum, U.S.; Fluidextractum Glycyrrhiza;, U.S. (Br.)
Mistura Glycyrrhizae Compositus (from Extract), U.S.; Pulvis Glycyrrhizae Compositus, U.S., Br.; Species Pectoralis, N.F.; Fluid glyceratum.
Glycyrrhizae, N.F.; Mistura Ammonii Chloridi (from Pure Extract), N.F.; Syrupus Glycyrrhizae (from Fluid glycerate),