Page 247 - Pharmacognosy 2 PG303

Pharmacognosy-2 (PG303) Level 2 Clinical Pharmacy-Pharm D

5- Part of a single fiber. 12- Fragment of a bordered
pitted vessel.
6- Fragment of a large vessel 13- Part of a medullary ray in
with elongated pits. radial longitudinal section
with underlying thin-
walled parenchyma and
part of a bordered pitted
vessel
7- Part of a group of smaller
vessels with bordered pits.

Tests for Identity
1- Test for sugars: Boil I gm of Liquorice, in powder or in thin shavings, with
20cc of water for 10 minutes. Filter, mix 5cc of filtrate with 5cc of
Fehling's solution and warm, a red precipitate of copper oxide produced.
2- Mix a little powdered Liquorice with 1-2 drops of 66% sulfuric acid, an
orange red color is produced.
3- Shake the aqueous decoction of Liquorice, a voluminous froth is
produced.

Tests for purity
Powdered Liquorice contains no foreign starch granules (flour), no yellow
masses (curcuma), no sclereids (olive stones).

Constituents
2-15% triterpenoid saponins, mainly glycyrrhizin (ammonium and calcium
salts of glycyrrhizinic acid) and 24-hydroxy-glycyrrhizin, which taste 50 and 100
times as sweet as sucrose, respectively. On hydrolysis, glycyrrhizinic acid affords
diglucuronic acid and the aglycone glycyrrhetinic acid. There are, in addition, many
other triterpenoid saponins, some of whose aglycones are known, e.g. glabranin-A
and B, glycyrrhetol, glabrolide, isoglabrolide... etc. Triterpenes, sterols are β-
amyrene, onocerin, β –sitosterol and stigmasterol.

More than 30 flavonoids and iso-flavonoids; and coumarins as herniarin,
umbelliferone, etc.

Uses
I- As an expectorant with secretolytic and secretomotor actions for cough
and bronchial catarrh, also for inflammation of the upper respiratory tract. The
active substances are saponins, especially glycyrrhizinic acid, which also has
bacteriostatic and antiviral activity. The saponins inhibit the growth of influenza A
viruses in hen embryo. The antiviral action is based on the induction and

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