PDR for Herbal Medicines

470 /LICORICE PDR FOR HERBAL MEDICINES

DESCRIPTION

Medicinal Parts: The medicinal parts are the unpeeled, dried

roots and the runners, the peeled dried roots, and the rhizome

with the roots.

Flower and Fruit: The axillary inflorescences are upright.

spike-like and 10 to 15 cm long. The individual flowers are 1

to 1.5 cm long, bluish to pale violet and short-pedicled. The

calyx is short, bell-shaped and glandular-haired. The tips of

the calyx are longer than the tube, and are pointed lanceolate.

The petals are narrow, the carina petals are not fused, and

they are pointed but not beaked. The fruit is a pod, 1.5 to 2.5

cm long, and 4 to 6 mm wide. It is erect and splayed, flat

with thick sutures, glabrous, somewhat reticulate-pitted, and

usually has 3 to 5 brown, reniform seeds.

Leaves, Stem and Root: The plant is a herbaceous perennial.

It is 1 to 2 m high and has a long sturdy primary taproot. The

taproot is 15 cm long and subdivides into 3 to 5 subsidiary

roots, 1.25 m in length. There are several horizontal woody

stolons which may reach 8 m. New stems are produced every

year. They are sturdy, erect, branched either from the base or

from further up, and are generally rough at the top. The

foliage leaves are alternate, odd pinnate and 10 to 20 cm

long. The leaflets are in 3 to 8 pairs. The stipules are very

small and drooping.

Habitat: Individual varieties of Glycyrrhiza are found in

different regions. Glycyrrhiza glanulifera is found in south-

eastern Europe and western Asia. Glycyrrhiza pallida and

violocea are found in Iraq. Glycyrrhiza typica is indigenous

to southern Europe and southwest Asia.

Production: Licorice root consists of the peeled and un-

peeled, dried roots and stolons of Glycyrrhiza glabra.

I irnrir^jtiipg is the extract of Glycyrrhiza glabra.

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Other Names: Sweet Root, sweet wort
ACTIONS AND PHARMACOLOGY
COMPOUNDS: LICORICE EXTRACT
Triterpene saponins (3-15%): (according to DAB 1996, 4-
6% in the adjusted Licorice extract, according to D AC 1995,
5-7% in the dry Licorice extract): chief components are
glycyrrhetic acid (sweet-tasting, aglycone 18 beta^glycyr-
rhetic acid, salts termed glycyrrizin)

Flavonoids: aglycones, including liquiritigenin, isoliquiri-

tigenin (its chalcone), isolicoflavonol

Isoflavonoids: aglycones formononetin, glabren, glabridin,
glabrol, 3-hydroxyglabroI, glycyrrhisoflavone

Cumestan derivatives: glycyrol, isoglycyrol, liqcoumarin

Hydroxycoumarins: including herniarin, umbelliferone, gly-
cycoumarin, licopyranocumarin

Steroids: sterols, including beta-sitosterol, stigmasterol

The drug contains considerably more free flavonoid and

isoflavonoid aglycones than the root drug does, due to the

hydrolysis that takes place during the extraction procedure.

COMPOUNDS: LICORICE ROOT

Triterpene saponins (3-15%): chief components glycyrrhetic

acid (sweet-tasting, aglycone 18beta-glycyrrhetic acid, salts

termed glycyrrhizin), 18-alpha-glycrrhetic acid, glycyrrhetic

acid methyl ester, glabric acid, glabrolide, uralenic acid

Flavonoids: aglycones including liquiritigenin, isoliquiritige-

nin (its chalcone), isolicoflavonol, isoliquiritin, licoricidin

Isoflavonoids: aglycones formononetin, glabren, glabridin,

glabrol, 3-hydroxygIabrol, glycyrrhisoflavone

Cumestan derivatives: glycyrol, isoglycyrol, liquocoumarin

Hydroxycoumarins: including herniarin, umbelliferone, gly-

cycoumarin, licopyranocoumarin

Steroids: sterols, including beta-sitosterol, stigmasterol

Volatile oil (very little): with anethole, estragole, eugenol,

hexanoic acid

EFFECTS: LICORICE EXTRACT AND ROOT

Anti-Inflammatory/Anti-platelet Effects

Glabridin exerts anti-inflammatory effects through inhibition

of tyrosinase activity, superoxide anion production, and

cyclooxygenase activity (Yokota, 1998). Licoricidin, a

potent compound in the root, has an inhibitory effect on

isoPAF(platelet-activating factor) acetyltransferase resulting

in anti-inflammatory activity (Nagumo, 1999). Isoliquiritige-

nin, an aldose reductase inhibitor, exerts anti-platelet effects

through inhibition of cyclooxygenase, lipoxygenase, and

peroxidase activity (Tawata, 1992). The anti-inflammatory

effects of glycyrrhizin is attributed to its anti-thrombin action

through inhibition of thrombin induced platelet aggregation

(Francischetti, 1997).

Antiulcer Effects

Licorice has protective effects against gastric ulcers induced

by aspirin (Dehpour, 1994). Licorice has the ability to

release endogenous secretin, which is a potential mediator of

the antiulcer actions (Shiratori, 1986). Carbenoxolone, a

succinate derivative of glycyrrhetic acid, has been shown to

accelerate the healing of ulcers (Barbara, 1979; Bianchi,

1985). Deglycyrrhizinated licorice is also effective for

healing ulcers and lacks undesirable side effects seen with

carbenoxolone (Morgan, 1982).