Family: Fabaceae (Leguminosae), Glycycrhiza glabra L.

Source: Simon, J.E., A.F. Chadwick and L.E. Craker. 1984. Herbs: An Indexed Bibliography. 1971-1980. The Scientific Literature on Selected Herbs, and Aromatic and Medicinal Plants of the Temperate Zone. Archon Books, 770 pp., Hamden, CT.

Licorice, Glycycrhiza glabra L., has long been prized for the roots and rhizomes (collectively called roots), which are used for flavoring and medicinal purposes. Native to the Mediterranean region and to central through southwest Asia, the plant is produced principally in Spain, France, Italy, Greece, Iran, Iraq, Turkey, and Syria (11.7-74). Reaching a height of 1 to 1.5 meters, the perennial plant has dark green leaflets, yellow, blue, or violet flowers, and sweet-flavored rhizomes.

The reported life zone of licorice is 6 to 25 degrees centigrade with an annual precipitation of 0.3 to 1.1 meters and a soil pH of 5.5 to 8.2 (4.1-31). The plant prefers deep sandy oil located in warm regions that have long photoperiods.

Although the plant can be grown from seed, commercial plantings are usually propagated from vegetative cuttings of rhizomes, suckers, or crowns (14.1-29). Marketable-size rhizomes develop in three to five years. Harvesting takes place in the autumn, after the foliage has dried. Commercial licorice is available in many forms, including sticks, peeled or unpeeled, solid extract, and block juice.

Licorice contains glycycrhizin, saponin, asparagine, sugars, resin, bitter principles, a volatile oil, and other compounds (6.1-29, 11.1-136, 14.1-35). Commercial glycyrrhizin is the ammoniated form of glycyrrhzic acid, which tends to intensify other flavors, such as chocolate and maple (11.1-74) .

Glycyrrhizin, the main constituent of licorice, is more than fifty times sweeter than cane sugar (11.1-74). The powdered licorice root is employed as a natural sweetner in alcoholic and nonalcoholic beverages, confections, and pharmaceuticals. Licorice is often mixed with anise oil, which has a licorice-like scent, for use as candy or in flavoring of other candies, pastries or baked goods. Licorice extract has been used as a foaming agent in fire extinguishers (11.1-67).

As a medicinal plant, licorice has been considered a demulcent, diuretic, emollient, expectorant, laxative, pectoral, and stomachic. Folk remedies call for licorice to be used against asthma, bronchitis, coughs, fevers ulcers, and cancers (11.1-97, 14.1-17). Licorice is known to have mineralocorticoid, spasmolytic, and estrogenic properties (7.8-10). The bark of licorice plants contains a hemolytically active saponin. Glycycrhetinic acid, a constituent of glycycrhizin, is used in the commercial preparation of carbenoxolone, employed as an anti-inflammatory agent against gastric ulcers and in the treatment of Addison's disease (11.1-74). Excessive licorice is known to promote cardiovascular toxicity, hypertension, and edema (11.1-136). Metabolic effects may occur in individuals consuming only modest amounts (7.8-20).

The licorice of commerce is derived from several varieties of Glycyrrhiza glabra L., including var. typica (Spanish), var. glandulifera (Russian), and beta-ulolacea (Persian). Glycyrrhiza uralensis Fisch., Chinese licorice, has long been used in treatment of ulcers and Addison's disease (11.1-97). Wild licorice refers to Aralia nudicaulis L. of the Araliaceae family.

Licorice is generally recognized as safe for human consumption as a natural flavoring and plant extract (21 CFR sections 182.10, 182.20 [1982]).

[Note: References listed above in parentheses can be found in full in the original reference].

Aromatic and Medicinal Plants Index

Last modified 6-Dec-1997