Drugs & Medication

Liquorice
Scientific classification
Kingdom: Plantae   Division: Magnoliophyta   Class: Magnoliopsida   Order: Fabales   Family: Fabaceae   Subfamily: Faboideae   Tribe: Galegeae   Genus: Glycyrrhiza   Species: G. glabra
Binomial name
Glycyrrhiza glabra

Liquorice or licorice (pronounced IPA: ['lɪkəʀɺɪʃ]) is the root of Glycyrrhiza glabra, from which a sweet flavour can be extracted. The liquorice plant is a legume (related to beans and peas) and native to southern Europe and parts of Asia. It is a herbaceous perennial, growing to 1 metre in height, with pinnate leaves about 7–15 centimetres (3–6 inches) long, with 9–17 leaflets. The flowers are 0.8–1.2 cm (1/3 to 1/2 inch) long, purple to pale whitish blue, produced in a loose inflorescence. The fruit is an oblong pod, 2–3 centimetres (about 1 inch) long, containing several seeds.

Contents 1 Cultivation and uses 1.1 Culinary use 1.2 Medicinal use 2 External links

Cultivation and uses

Liquorice is grown as a root crop mainly in southern Europe. Very little commercial liquorice is grown in North America, where it is replaced by a related native species, American Licorice (G. lepidota), which has similar uses.

Liquorice extract is produced by boiling liquorice root and subsequently evaporating most of the water (in fact, the word 'liquorice' is derived from the Ancient Greek words for 'sweet root'). Liquorice extract is traded both in solid and syrup form. Its active principle is glycyrrhizin, a sweetener more than 50 times as sweet as sucrose which also has pharmaceutical effects. The related Chinese Liquorice (G. uralensis), which is used extensively in traditional Chinese medicine, contains this chemical in much greater concentration.

Culinary use

Liquorice flavour is found in a wide variety of liquorice candies. The most popular in the United Kingdom are very sweet Liquorice Allsorts. In continental Europe, however, far stronger, saltier candies are preferred. It should be noted, though, that in most of these candies the taste is reinforced by aniseed oil, and the actual content of liquorice is quite low. Additionally, liquorice is found in some soft drinks (such as root beer), and is in some herbal teas where it provides a sweet aftertaste. The flavour is common in medicines to disguise unpleasant flavours.

Liquorice is popular in Italy, particularly in the South, in its natural form. The root of the plant is simply dug up, washed and chewed as mouth-freshener. Throughout Italy unsweetened liquorice is consumed in the form of small black pieces made only from 100% pure liquorice extract; the taste is bitter and intense.

In Britain and The Netherlands in the past dried liquorice root [1] was chewed as a sweet by youngsters.

Chinese cuisine uses liquorice as a culinary spice for savoury foods. It is often employed to flavour broths and foods simmered in soy sauce.

Other herbs and spices of similar flavour include Anise, star anise, tarragon, and fennel.

Medicinal use

Powdered liquorice root is an effective cough remedy (expectorant), and has been used for this purpose since ancient times, especially in ayurvedic medicine where it is also used in tooth powders. Modern cough syrups often include liquorice extract as an ingredient. Additionally, licorice may be useful for both mouth ulcers [2] and peptic ulcers [3]. Naturopathic medicinal uses include treatment of peptic and oral ulcers.

Liquorice is also a mild laxative. Large doses of glycyrrhizinic acid and glycyrrhetinic acid in liquorice extract can lead to hypokalemia and serious increases in blood pressure, a syndrome known as apparent mineralocorticoid excess. These side effects stem from the inhibition of the enzyme 11β-hydroxysteroid dehydrogenase (type 2) and subsequent increase in activity of cortisol on the kidney. 11β-hydroxysteroid dehydrogenase normally inactivates cortisol in the kidney; thus, licorice's inactivation of this enzyme makes the concentration of cortisol appear to increase. Cortisol acts at the same receptor as the hormone aldosterone in the kidney; thus, the effects mimic aldosterone excess, although aldosterone remains low or normal during licorice overdose. Cortisol does not actually increase either; however, its activity in the kidney effectively increases due to the disabling of this enzyme. To decrease the chances of these serious side effects, deglycyrrhizinated licorice (DGL) preparations are available.

Licorice affects the body's endocrine system. It can lower the amount of serum testosterone, but whether it affects the amount of free testosterone is unclear. A PubMed search for licorice AND testosterone will provide additional information.

The disabling of similar enzymes in the gut by glycyrrhizinic acid and glycyrrhetinic acid also causes increased mucus and decreased acid secretion. Thus, licorice may in moderate amounts soothe an upset stomach and is used as an aid for healing stomach ulcers.

Recently, a study is being conducted by clinical psychologist Hunna Watson into the therapeutic potential of liquorice on people with mood disorders.

External links

• National Institute of Health - Medline
• PDRhealth.com - Profile of Deglycyrrhizinated Licorice (DGL)
• Chemical & Engineering News article on Licorice
• Non-profit dedicated to promoting licorice / liquorice - Information, recipes, newsgroups about many aspects of licorice