Glycyrrhizin

Structural formula
General
Surname	Glycyrrhizic acid
other names	(3 β , 20 β ) -20-carboxy-11-oxo-30-norolean-12-en-3-yl-2- O- β- D -glucopyranuronosyl-β- D -glucopyranosiduronic acid Glycyrrhizin
Molecular formula	C 42 H 62 O 16
Brief description	very sweet tasting crystals
External identifiers / databases
CAS number 1405-86-3 EC number 215-785-7 ECHA InfoCard 100.014.350 PubChem 14982 ChemSpider 14263 DrugBank DB13751 Wikidata Q418705
properties
Molar mass	822.94 g mol −1
Physical state	firmly
Melting point	220 ° C
solubility	almost insoluble in cold water (0.053 mg l −1 at 25 ° C) soluble in hot water and ethanol
safety instructions
GHS hazard labeling no classification available
Toxicological data	5571 mg kg −1 ( TD Lo ,  human ,  oral )
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Licorice ( Glycyrrhiza glabra )

Glycyrrhizin or glycyrrhizic acid is a saponin and triterpenoid that occurs naturally in the roots of the licorice plant ( Glycyrrhiza glabra ). The glycoside that is used to make liquorice is also found in other plants such as the fruit of the grapefruit tree. It tastes about 50 times sweeter than cane sugar and also serves as a natural sweetener .

Medical importance

As can be seen from the formula, glycyrrhizin contains two sugar residues in each molecule. These are hydrolytically split off in the digestive tract by bacterial activity . This creates the aglycon glycyrrhetinic acid. This is an inhibitor of 11 β -hydroxysteroid dehydrogenase 2 . That enzyme catalyzes the inactivation of cortisol by converting it into cortisone . Since the inactivation of cortisol is now reduced, the effect of cortisol increases. Cortisol acts not only as a glucocorticoid , but also as a mineralocorticoid , stimulating the same mineralocorticoid receptor as aldosterone (which acts primarily as a mineralocorticoid) . Aldosterone as caused cortisol a water - and sodium - retention and increased potassium excretion, in the situation described in an extent which would otherwise only at a too high aldosterone in blood plasma ( hyperaldosteronism can be found).

The aldosterone concentration in the blood plasma is regulated by the renin-angiotensin-aldosterone system . This system also involves negative feedback ; H. if the aldosterone effect is too great, the plasma concentration of aldosterone (and also of renin ) falls . This also happens in the situation described, but at the mineralocorticoid receptor the greater cortisol effect outweighs the lower plasma concentration of aldosterone and simulates hyperaldosteronism. Symptoms of the same as high blood pressure or water retention occur. Rhabdomyolysis , myopathy, and kidney failure can be serious .

safety instructions

The Scientific Committee for Food of the European Commission recommends not consuming more than 100 mg glycyrrhizic acid per day. How exactly the consumer can comply with this is unclear, as no specific content information for glycyrrhizic acid has to be declared.

In the implementation of Directive 2004/77 / EC, however, labeling has been mandatory since May 2005. According to the Food Labeling Ordinance (LMKV), sweets and beverages must have a content of 100 mg / kg or more. 10 mg / L contain the information "Contains liquorice" , from a content of 4 g / kg or 50 mg / L the addition "Contains liquorice - if you have high blood pressure, excessive consumption of this product should be avoided" .

Individual evidence

1. ↑ ^{a b} Entry on Glycyrrhizin. In: Römpp Online . Georg Thieme Verlag, accessed on December 28, 2014.
2. ↑ ^{a b c} Entry on glycyrrhizin in the ChemIDplus database of the United States National Library of Medicine (NLM)
3. ↑ This substance has either not yet been classified with regard to its hazardousness or a reliable and citable source has not yet been found.
4. ^ Toxicologist. Vol. 54, p. 109, 2000.
5. ↑ Scientific Committee on Food: Opinion Of The Scientific Committee On Food On Glycrrhizinic Acid And Its Ammonium Salt (PDF; 247 kB).
6. ↑ OJ. L 109 of April 30, 2004: Commission Directive 2004/77 / EC (PDF; 88 kB) .