Page 98 - Pharmacognosy 02-06203
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Spanish consists mainly of Usually
liquorice: cultivated stolons and few pieces unpeeled.
Russian of roots
liquorice:
wild consists mainly of Usually peeled.
roots
Macroscopical Examination:
(See The Practical)
Microscopical Examination:
(See The Practical)
Powdered drug:
(See The Practical)
Constituents:
1-Triterpene saponin glycosides a- Most of the sweet taste of liquorice
is due to glycyrrhizin which is the potassium & calcium salts of
glycyrrhizinic (glycyrrhizic) acid.
Glycyrrhizin is 50 times as sweet as sucrose, it loses its sweet taste on
hydrolysis and is converted to a triterpene aglycon glycyrrhetenic
(glycyrrhetic) acid + 2 molecules of glucuronic acid (a sugar acid related
to glucose).
b- Another triterpene aglycon liquiritic acid (isomer of glycyrrhetic acid)
is also present.
2-Anti-oxidant compounds (Flavonoids):
• The yellow colour of liquorice is due to liquirtin and isoliquertin; both
are flavones; present either as glycosides or free aglycons.
• Isoflavones and chalcones are also present.
3- Other constituents:
5-15% sugars (glucose and sucrose), starch & the bitter principle
(Glycyrramarin) which is present in the cork of Russian variety, so it
should be peeled.
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