Liquorice (glycyrrhiza glabra linn.)

Pharmacognosy
YTIP, University of Mumbai
final year B.Pharm

1. LIQUORICE
Glycyrrhiza glabra
Guided by –Prof. Dr. BabitaMore
Department of Pharmacognosy
YadavraoTasgaonkarInstitute of Pharmacy
University of Mumbai
Prepared by –Rohan Jagdale
Final year B.Pharm
[email protected]

2. Content Objectives
Introduction
Saponin glycosides
Stolon Vs Rhizome
Collection & cultivation
Extraction
Active constituents
Morphology of liquorice root
T.S. of liquorice root & stolon and T.S. of stem (diagram)
Chemical identification
Powder microscopy
Uses

3. Introduction
❑Common names: Liquorice, Sweet Wood, Regolizia(Italian),Mulethi(hindi),
Jeshtamadh, Yastimadhu. (marathi)
❑also known as Liquoriceplant
❑Meaning:Glycyrrhiza –sweet root & glabra –smooth
❑Biological sources: It is obtained from the dried, unpeeled, roots and stolonsof
Glycyrrhiza glabra.
❑Family:Leguminosae
❑Part used: Roots & Stolons
❑Geographical Source: commercially cultivated in Spain, and England. Also grown in
the sub-Himalayan tracts and Baluchistan.
❑Flowers: Purplish blue colour
❑For drug preparation: dried unpeeled roots & stolonsare used

4. Saponin Glycosides
“ Sapo” is Latin name for a soap (soap-like)
Group of organic compounds that form when shaken with water even in dilute
solution.
Saponins cause haemolysisof red blood cells.
According to the nature of the aglycone, saponins are classified into Steroidal &
Triterpenoidalsaponins .
TriterpenoidalSaponins are very common in Dicot plants
It contains 30 carbon atoms
E.g. Liquoriceroot : glycyrrhizin

5. Difference between stolon & rhizome
The key difference between rhizome and stolon is that rhizome is the root-like main
stem that grows underground while stolon is a stem sprouted from the existing stem
that runs horizontally just below the soil surface to form a new plant and connect
with the mother plant.

6. Collection & Cultivation
The plant requires a deep well cultivated fertile moisture-retentive soil for good root
production. Prefers a sandy soil with abundant moisture and does not flourish in clay.
Slightly alkaline conditions produce the best plants. It is propagated using seeds and
roots. The seeds are presoaked for 24 h in warm water and then sown in spring or
autumn in a greenhouse.
They are transplanted in late spring or early summer when in active growth.
Harvesting generally occurs in the autumn of the fourth year. Some are peeled and
cut up into short lengths before drying, but much is now used unpeeled. The drug is
imported in bales.

7. Extraction
Licorice (glycyrrhiza) root is the dried & ground rhizome & root portions of Glycyrrhiza
glabra or other species of Glycyrrhiza.
Licorice extract is that portion of the licorice root i.e, after maceration (Softening by
soaking in a liquid), extracted by boiling water. The extract can be further purified by
filtration and by treatment with acids and ethyl alcohol.
Licorice extract is sold as a liquid, paste (block), or spray-dried powder.
Licorice paste is preferred for flavoring purposes whereas the powdered licorice is
used in confectioneries and pharmaceutical products.
Ammoniated glycyrrhizinis prepared from the water extract of licorice root by acid
precipitation followed by neutralization with dilute ammonia.

8. Active constituents
❑Main constituent -Glycyrrhizin:A triterpenoidalsaponin glycoside.
❑Glycyrrhizin (5 –12 % ), which is mixture of potassium and Calcium salts of glycyrrhizinicAcid .
❑Glycyrrhizicacid causes sweetness in liquorice& is fifty times sweeter than sucrose.
❑Flavonoids (Liquiritinand isoliquiritin), which cause the yellow colorof the drug.Presence of
flavonoid (liquiritinand isoliquiritin) cause antigastriceffect and it is useful in peptic ulcers.
❑Bitter principles (Glycyramarin), mainly in the outer tissues and are therefore absent in the
peeled varieties.
❑Asparagine (2-4 %)
❑Vitamins B1, B2, B3, B6, and E.
❑Sugars (5-15%), starch, and proteins.

9. Glycyrrhizin Ammoniated glycyrrhizin Glycyrrhizicacid
Sugar
chain
Aglycone

10. Morphology of Liquoriceroots
Color: unpeeled –dark reddish-brown & peeled –yellow, fibrous
exterior
Taste: sweet
Size : 4 to 20 cm x 0.5 to 2 cm
Stolonsare smaller in diameters than roots
Shape: cylindrical
Surface (Outer): Yellowish brown with longitudinal wrinkles (unpeeled);
peeled ones are yellow colouredwith fine longitudinal ridges. In case of
stolons, scars of the buds can be seen;
Fracture: Coarsely fibrous in the bark region and splintery in the wood;
fractured surface shows long fibresprojecting outwards
Special features : scaly , purplish cork
longitudinal ridges (older pieces)

11. Transverse section Histology:
The Rhizome (stolons):
▪The Cork:It forms a thick zone of several layers of flattened polygonal, thin-walled cells.
▪The Cortex (Phelloderm in root): It is a narrow zone composed of parenchyma cells containing
isolated prisms of calcium oxalate and simple starch granules.
▪The Pericycle: Parenchymatous with small groups of lignified fibers.
▪The Phloem: It is a wide zone, traversed by numerous wavy, funnel-shaped medullary rays. It
consists of numerous groups of fibers, each surrounded by a sheath of parenchyma cells, each
containing a prism of calcium oxalate, and sieve tissue. Phloem fibers are very long, with a very
narrow lumen and strongly thickened walls .
▪The Xylem: It is radiate consisting of parenchyma, groups of fibers, tracheidsand large wide-lumen
vessels, with numerous bordered pits and slit-shaped openings. Parenchyma cells contain starch
granules.
▪The Pith: Present only in the rhizome and is parenchymatous.

12. Cork
Phelloderm
Phloem fibers
Phloem parenchyma
Cambium
Vessels
Xylem fibers
Xylem parenchyma
Medullary ray
pith
T.S. of Liquorice root T.S. of Liquorice stolon

13. T.S of Liquoriceroot T.S of Liquoricestolon
Shows presence of polyhedral tubular
brownish cork cells.
Also shows presence of polyhedral
tubular brownish cork.
Absence of pith, shows tetrarch xylem. Presence of pith.
Presence of medullary rays Absence of medullary rays
Presence of cortex Presence of cortex
•Unpeeled drug shows presence of polyhedral tubular brownish cork cells.
•Thick, lignified fibres in phloem and xylem.
•Calcium oxalate are present in parenchyma.
•In stolons, pith is present and it is parenchymatous.
•Root is characterized by presence of tetrarch xylem (four centripetally developed
xylem plates)and absence of pith

14. T.S. of Stem

15. Chemical identification
Mix a small amount of powdered Liquoricewith 1 or 2 drops of sulfuric acid
(66% v/v): an orange-red color is produced
Section of drug + 80% H2SO4 : Show Yellow Color
Histo-chemical evaluation : Stem powder of Glycyrrhiza glabra treated with
various reagents to detect the presence and absence of lignified cells,
tannin, starch, calcium oxalate crystals etc
Sr.No.Reagents Observations Characteristics
1 Phloroglucinol+Conc. Hcl Red Lignified cells
2 FeCl3 solution Dark blue to BlackTannin cells
3 Iodine solution Blue Starch
4 Phloroglucinol+Conc. Hcl Dissolved Calcium oxalate crystal
Histochemical evaluation of Glycyrrhiza glabra Linn. stem

16. Powdered liquoricMicroscopical
Identification:
Powdered Liquoriceis characterized by its light yellow color,
faint characteristic odor and its sweet taste.
Microscopically, it is characterized by:
1-Cork in surface view (1).
2-Numerous fragments of fibers accompanied by crystal sheath
(10).
3-Fragments of large vessels with wide lumen, having
numerous, oval bordered pits (6, 7, 12).
4-Prisms of calcium oxalate (9, 10).
5-Numerous starch granules, mostly simple, free (3) or in cells.

17. Powder microscopy
Organoleptic characters :
Yellowish in colour, sweetish in taste, sweet
smell and fibrous in touch.
Microscopic characters :
Diagnostic microscopic characters shows starch
grain in groups, crystal fibers, cork in surface
view, rhomboidal crystals, lignified fibers,
simple starch grain,
tannin content and border pitted vessels.

18. Uses
Glycyrrhiza has demulcent(cough suppressant) and expectorant properties.
Glycyrrhizin is a natural sweetener that is extracted from licorice root. It does ,have
a zero glycemic index and is consequently suitable for diabetics.
It is used as a masking agent for bitter drugs in pharmaceutical formulations, such
as: quinine, aloe, ammonium chloride etc.
Ammoniated glycyrrhiza is employed as a flavouringagent in beverages,
pharmaceuticals and confectionary.
The inherent surfactant activity due to the presence of saponins helps to facilitate
the absorption of poorly absorbed drugs .
The presence of glycyrrhetinicacid exert mineralocorticoid activity and hence it is
used in the treatment of inflamations, rhematoidarthritis and Addison’s disease.

19. References
https://cognosy4all.blogspot.com/2016/11/liquorice-licorice.html
https://www.iptsalipur.org/wp-content/uploads/2020/08/BP504T_PGPC_UNIT_II.pdf
https://www.slideshare.net/soniasingh183/liquorice-biological-source-cultivation-and-
collection-morphology-microscopy-238385441
https://www.researchgate.net/figure/fig1_281478934
https://www.slideshare.net/ALOKSINGH540/pharmacognosy-of-liquoricesaponin-glycoside
https://www.slideshare.net/MinPiyusha/13-fet1012-glycyrrhizic-acid
https://imagesday.com/photos/thank-you-images-for-ppt/
https://medcraveonline.com/JNMR/JNMR-07-00199.pdf