Liquorice, licorice or cultivated licorice is a perennial plant by its root which reaches 1m to 1m50, the flowers are grouped in erect clusters, of a more or less dark purple-lilac hue; the fruit is a small flattened pod, covered with hairs in some varieties, the foliage is pinnate with 10-20 leaflets, so nothing very noticeable. It looks like many other plants of this large plant family, the Fabacae, formerly legumes.
It is a plant from the Old World, there are several species and varieties.
Those that are most used are: Glycyrrhiza glabra in Europe and the Middle East, Glycyrrhiza uralensis in China (the complicated spelling of this plant genus is directly borrowed from ancient Greek).
Licorice is found in the wild and is now also cultivated in the Near East, China, Russia, Pakistan, USA and Spain.
It is an easy to grow plant with decorative foliage and flowers. The lateral roots (or runners) are harvested from the plants after 3 to 4 years of cultivation.
The root and the dried runners constitute the proper licorice and are the medicinal parts
CHEMICAL COMPOSITION AND PROPERTIES
LICORICE ROOTS AND RUNNERS
Starch (25 to 30%), sugars (3 to 10%), coumarins, sterols, and especially flavonoids and saponosides are found in licorice root, which are probably responsible for the pharmacological activity.
The main saponosides, glycyrrhisin is the more important, it corresponds to 3 to 5% of the dry plant sometimes more.
Glycyrrhizin (in the form of calcium, potassium and magnesium salts of glycyrrhizinic acid, soluble in water) releases by hydrolysis two molecules of glucuronic acid and one molecule of glycyrrhetinic acid (or glycyrrhetic acid, the international name of which is much easier to write: ENOXOLONE).
This chemical transformation of glycyrrhizin into ENOXOLONE is important because it is the molecule responsible for the majority of the pharmacological effects of licorice.
In the body, the glycyrrhizin absorbed by the oral route is not transformed before the intestine where intestinal bacteria ensure this hydrolysis and the release of enoxolone.
Among the flavonoids: glabridin and glabren are the two most studied compounds
LICORICE IS ESPECIALLY A SWEETENER
Licorice has a sweetening power 50 to 60 times greater than ordinary sugar. On the one hand, it is a flavor enhancer but it is also a bitterness attenuator.
The sweet taste is quite different from the banal sugar (sucrose) and above all it is more prolonged, "longer in the mouth" with a "vegetal" taste note typical of liquorice (but which is also found in stevia powder. )
LICORICE AND ITS EXTRACTS: PHARMACOLOGICAL PROPERTIES
Glycyrrhiza glabra and uralensis have long been used in traditional medicine in Europe and Asia.
They are still used for the same indications, but modern pharmacological studies show that these plants also contain compounds capable of acting both on cholesterol metabolism, as an antispasmodic, anti-hemorrhagic, as antivirals or anti-cancer drugs.
LICORICE. Action on the bronchopulmonary system:Whole liquorice is a traditional remedy for coughs, bronchial irritation and is an expectorant.
LICORICE. Action on the metabolism of corticosteroid hormones:
Glycyrrhizin alters the metabolism of corticosteroid hormones (secreted mainly by the cortical part of the adrenal gland) by inhibiting an important enzyme in the liver and kidney (11-beta-hydroxysteroid dehydrogenase) which normally converts cortisol (very active) into cortisone (much less active), there is a lot of inactive cortisone compared to cortisol (= hydrocortisone) which is very active as an hormone.
This inhibition or substitution of role is the starting point of a disorder which associates edemas, increase in arterial pressure (hypertension) and decrease in blood potassium (hypokalaemia) which can cause serious muscle disorders pseudo-paralytic (including cardiac)
It is a syndrome of pseudo hyperaldosteronism.
Enoxolone (glycyrrhetic acid see above) is 200 to 1000 times more active on this enzymatic system than pure licorice.
This effect on the regulation of electrolytes (mineralocorticoid effect) and therefore of body water is only felt after a large daily dose of licorice and in case of prolonged use.
The association of hypertension, edema, muscle weakness and cardiac arrhythmias is quite characteristic.
The disorders disappear in a few weeks if you stop taking liquorice.
The toxic threshold would be around one gram of glycyrrhizin per day (or about 20g of dry root or 80 to 100g of fresh root) over a prolonged period, but some people may show signs of intoxication at lower doses ( 300 to 400 mg / day)
LICORICE. Action on the digestive system:
Whole liquorice is a traditional remedy for gastralgia, dyspeptia and peptic ulcer disease.
We now know that licorice promotes an increased secretion of mucus in the stomach, which provides better protection of the stomach lining to which is added a local anti-inflammatory effect.
As the licorice-based treatment is limited in time due to the risk of disturbance of the mineralocorticoid metabolism, licorice extracts from which glycyrrhizin has been removed are also used.
It turns out that the anti-ulcer effect is still present, it is attributed to the action of flavonoids which are anti-inflammatory and which also limit the development of Helicobacter pylori main responsible for ulcerations of the mucous membrane of the stomach
LICORICE. Anti-inflammatory action:Liquorice extract (glycyrrhizin) has a local anti-inflammatory action (skin, mucous membrane) reminiscent of corticosteroids :
LICORICE. Immunostimulating, anti bacterial and antiviral action:Liquorice extracts and glycyrrhetic acid are weakly antibacterial, antiviral, healing and immunostimulating, apparently without toxic or mutagenic effects except for the mineralocorticoid disorders mentioned above.
LICORICE. Action on the metabolism of cholesterol, blood lipids and the metabolic syndrome associated with type 2 diabetes:
A recent study has shown the interest of licorice in reducing tissue resistance to insulin, the determining cause in the onset of type 2 diabetes and one of the difficulties in treating it.
The action of the regulator would be twofold: action on 11-beta-hydroxysteroid dehydrogenase at the tissue level and on another important enzyme, lipoprotein lipase.
LICORICE. Action on estrogen metabolism:We have long known the estrogenic action (feminization) of licorice root, it turns out that it is probably more flavonoids than glycyrrhizin that have a female hormone-like action.
LICORICE. Antitumor activity:
In Japan, the use of licorice to limit the progression of hepatitis (especially hepatitis C) has been shown to reduce the risk of developing liver cancer (hepatocarcinoma) .
In the laboratory, observation shows a clear slowing down of the development of cancer cells in certain types of prostate cancer and an anti-angiogenic effect (inhibition of the creation of new blood vessels and therefore limitation of cancerous development).
These anti-cancer effects are attributed to the flavonoids in licorice
USE OF LICORICE AND LIQUORICE EXTRACTS AS A FLAVORING
MANY PHYTOMEDICINES CONTAIN LICORICE OR LICORICE EXTRACTS
Anti-inflammatory liquorice extractsGlycyrrhetic acid (ENOXOLONE) is used locally as an alternative to the use of steroidal anti-inflammatory drugs, especially on the face : solar erythema (sunburn), inflammatory dermatitis of the face and eyelids, diaper rash .
Licorice extracts without GlycyrrhizinFor prolonged use in the treatment of gastric ulcers, it is best to use the extract without glycyrrhizin.
Licorice and hepatitisSince many years glycyrrhizin has been used in Japan to limit the development of hepatic disorders caused by the hepatitis C virus.
Licorice and BleedingANKAFERD is a mixture of plant extracts marketed in TURKEY based on Thymus vulgaris, Glycyrrhiza glabra, Vitis vinifera, Alpinia officinarum, and Urtica dioica.
LICORICE IN PRACTICE
In the event of regular consumption of liquorice extracts in drinks or confectionery it is imperative to calculate the amount of glycyrrhizin absorbed to reasonably limit it to 150 mg per day otherwise there is a risk of increased blood pressure and possibly the onset of heart rhythm disturbances.
Comply with the indications of the specialty for the dosage and duration of treatment
Liquorice powder or sticks.
You can make a licorice tea with licorice powder or finely fragmented roots or chew dried licorice roots to limit the urge to smoke or for oral hygiene.
Licorice paste is the result of a prolonged decoction of dried and crushed roots which are concentrated by evaporation.
EXAMPLES OF OTHER PLANTS CONTAINING GLYCYRRHIZIN
JEQUIRITY: ABRUS PRECATORIUS
This slender tropical liana is known for its pretty little black and red very decorative seeds which are used to make necklaces (in India they are used to weigh gold).
Both the stem and the root contain glycyrrhizin.
In the West Indies the infusion of the whole plant is used to calm the cough.
In other tropical regions, it is mixed with other plants to make an asthma syrup.
The seeds contain a violent and formidable poison: abrin.
A seed can kill a child. Fortunately the seed coats are very hard but there is always the fear that the string of pierced seeds will be worn in the mouth.
Abrin like many lectins (castor ricin, bean phasin) is destroyed by heat.
GLYCYRRHIZA LEPIDOTA or American Liquorice
Found in the western part of the North American continent, its slightly sweet root is traditionally eaten raw or cooked.
LICORICE LEAF ASTRAGALLUS GLYCYPHYLLOS OR LICORICE LEAF
Found in the dry and calcareous parts of the Mediterranean region, it is the leaves and flowers that contain a little glycyrrhizin.
A small fern found in the wet parts of the American Northwest (California and Alaska). Its rhizome contains a substance with a sweet taste similar to licorice but chemically different (polypodoside A)
COMMON POLYPOD or POLYPODIUM VULGARE
Very similar to the previous plant, present in Europe, it is a small fern whose rhizome is also slightly sweet.
The sweet component, osladine, is present in small amounts. This small, sometimes epiphytic fern is difficult to differentiate from other ferns whose rhizome can be bitter or poisonous.
A SWEETENER THAT CALMS DIGESTIVE PAIN
The pleasant taste and its sweetness (50 times that of normal sugar) make licorice used as a flavoring of many sweets, liqueurs or drinks.
It also contains a compound which protects the lining of the stomach and helps heal certain ulcers or gastritis. It is also used to reduce skin irritation (sunburn, dermatosis).
Licorice contains substances that are active against viruses, certain cancers or that slow the progression of hepatitis C.
Warning : its abuse in both confectionery and drinks can cause secondary hormonal disorders
Copyright 2021 : Dr Jean-Michel Hurtel