A comprehensive review on an important Unani drug mulethi (Root of Glycyrrhiza glabra Linn)

Abstract

The roots of a plant Glycyrrhiza glabra Linn constitute an important drug in the ancient Unani literature, commonly known as Mulethi or Aslus Soos or liquorice. It is one of the most widely used plants from the ancient medical history, both as a medicine and as a flavouring herb. Historically, liquorice has been used from more than 4000 years. The drug was also mentioned by Theophrastus and Dioscorides. It is interesting to find that it maintains even today its role in medicine and pharmacy. The plant is well suited to warm climatic conditions with long growing session. It grows best on sandy loam soils. The light soils promote better root development. Glycyrrhiza glabra Linn is a hardy herb or undershrub and a tall perennial plant attaining a height of 1.8 mt. The roots are sweet in taste, thick, having many branches with red or lemon color outside or yellowish or pale yellow inside. The underground part in some varieties consists of a rootstock with a number of long, branched stem, in others, the rootstock which is stout, throws off a large number of perennial roots. It is used for allaying coughs and catarrhal affections. It is also useful in irritable conditions of the mucous membranes of urinary organs. Its extract is a constituent of cough syrups, throat lozenges and pastilles and it is employed in the form of aromatic syrups and elixirs for masking the taste of nauseous medicines. The extract is reported to exert a healing effect on gastric ulcers, is also reported to be useful in treatment of Addison's disease. Externally liquorice is applied with ghee and honey for cuts and wounds. Keeping in view the high medicinal importance of the drug in Unani Medicine, the present review provides available information on traditional uses, phytochemistry and pharmacological properties of the Unani drug Mulethi.

Full text

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Journal of Pharmacognosy and Phytochemistry 2021; 10(3): 488-493
E-ISSN: 2278-4136
P-ISSN: 2349-8234
www.phytojournal.com
JPP 2021; 10(3): 488-493
Received: 01-03-2021
Accepted: 03-04-2021
Shaihba Firoz Ahmed
Department of Ilmul Atfal, Al-
Ameen Unani Medical College,
Malegaon, Maharashtra, India
Mohd Sajid
Department of Tahaffuzi Wa
Samaji Tib, Mohammadia Tibbia
College, Malegaon, Maharashtra,
India
Wasim Ahmad
Department of Ilmul Advia,
Mohammadia Tibbia College,
Malegaon, Maharashtra, India
Fahmeeda Zeenat
Department of Amraze Niswan
Wa Atfal, Faculty of Unani
Medicine, AMU, Aligarh, Uttar
Pradesh, India
Mohammad Shakir
Department of Tahaffuzi Wa
Samaji Tib, Mohammadia Tibbia
College, Malegaon, Maharashtra,
India
Corresponding Author:
Shaihba Firoz Ahmed
Department of Ilmul Atfal, Al-
Ameen Unani Medical College,
Malegaon, Maharashtra, India
A comprehensive review on an important Unani
drug mulethi (Root of Glycyrrhiza glabra Linn)
Shaihba Firoz Ahmed, Mohd Sajid, Wasim Ahmad, Fahmeeda Zeenat
and Mohammad Shakir
Abstract
The roots of a plant Glycyrrhiza glabra Linn constitute an important drug in the ancient Unani literature,
commonly known as Mulethi or Aslus Soos or liquorice. It is one of the most widely used plants from the
ancient medical history, both as a medicine and as a flavouring herb. Historically, liquorice has been used
from more than 4000 years. The drug was also mentioned by Theophrastus and Dioscorides. It is
interesting to find that it maintains even today its role in medicine and pharmacy. The plant is well suited
to warm climatic conditions with long growing session. It grows best on sandy loam soils. The light soils
promote better root development. Glycyrrhiza glabra Linn is a hardy herb or undershrub and a tall
perennial plant attaining a height of 1.8 mt. The roots are sweet in taste, thick, having many branches
with red or lemon color outside or yellowish or pale yellow inside. The underground part in some
varieties consists of a rootstock with a number of long, branched stem, in others, the rootstock which is
stout, throws off a large number of perennial roots. It is used for allaying coughs and catarrhal affections.
It is also useful in irritable conditions of the mucous membranes of urinary organs. Its extract is a
constituent of cough syrups, throat lozenges and pastilles and it is employed in the form of aromatic
syrups and elixirs for masking the taste of nauseous medicines. The extract is reported to exert a healing
effect on gastric ulcers, is also reported to be useful in treatment of Addison’s disease. Externally
liquorice is applied with ghee and honey for cuts and wounds. Keeping in view the high medicinal
importance of the drug in Unani Medicine, the present review provides available information on
traditional uses, phytochemistry and pharmacological properties of the Unani drug Mulethi.
Keywords: Glycyrrhiza glabra, mulethi, aslus-soos
Introduction
The root of Glycyrrhiza glabra Linn commonly known as Mulethi/Aslus Soos/liquorice sweet
wood is one of the most widely used herb from the ancient medical history, both as a medicine
and as a flavouring herb [1].
It is native to Mediterranean and certain areas of Asia [2]. The liquorice is to genus Glycyrrhiza
which contains about 14 species [3]. The word Glycyrrhiza is derived from Greek term glykos
(meaning sweet) and rrhiza (meaning root). Glycyrrhiza glabra belongs to leguminous family
[1].
Historically liquorice has been used from more than 4000 years. The earliest record of its use
in medicine is found in code Humnubari (2100 BC). It was also one of the important plants
mentioned in Assyrian herbal (400 BC) mentioned its use as a remedy of ulcers and quenching
of thirst. The drug was also mentioned by Theophrastus and Dioscorides [3].
Fig 1: Glycyrrhiza glabra

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Journal of Pharmacognosy and Phytochemistry http://www.phytojournal.com
It is interesting to find that even to this day liquorice
maintains its role in medicine and pharmacy [4].
It is a tall perennial shrub, leaves compound, imparipinnate,
alternate in 4-7 pairs of oblong, elliptical or lanceolate leaflet.
Flowers are in axillary spikes, lavender to violet in colour.
Pods up to 1.5 cm long, erect, glabrous and 3-5 brown,
reniform seeds [3].
Cultivation
Attempts have been made to cultivate G. glabra in several
places of India, notably Baramulla, Srinagar and Jammu in
Kashmir, Dehradun and Delhi. Its cultivation is likely to be
successful in the temperate Himalaya’s and in the hilly
districts of south India [5]. The crop can be successfully
cultivated in Haryana [6].
Climate and soil
The crop is well suited to warm climatic conditions with long
growing session. It grows best on sandy loam soils. The light
soils promote better root development [6].
Root yielding and storage
Roots are ready for harvest after 2.5-3 years of planting.
Digging should be done preferably in February so that the
root cutting can be used for further planting. Normally the
root contains 50-60% moisture and should be dried in sunlight
for 2-3 days and then in shade for 4-5 days. The roots are cuts
into pieces of 15-20 cm. and are stored after complete drying.
Preferably the roots should be classified in various categories
according to thickness [6].
Occurrence and distribution
It is native to the Mediterranean countries and China. The
drug is imported into India from Asia Minor, Iraq, Persia and
other central Asian countries [7]. It is cultivated in Jammu and
Kashmir, Punjab and sub Himalayan tracts [8], Arabia,
Persian, Gulf, Afghanistan, Asia Minor, Siberia etc. [9]. Root
is also cultivated in the Punjab, sub Himalayan tracts from the
Chenab eastwards, Sind and Peshawar valley, Burma and
Andaman Islands [10]. It is also distributed in the sub-tropical
and warm temperate regions of the world, none of the
liquorice yielding species occurs in India, but cultivation of
Glycyrrhiza glabra on an experimental scale has been
undertaken in several places [5] like Delhi, Indore and Anand.
A Russian accession was found suitable in terms of growth,
yield and glycyrrhizin content at Indore and Anand. The crop
can be successfully cultivated in Haryana [6]. The Egyptian
variety is considered superior to Arabic and Turkish varieties
[7].
Ethnobotanical description
It is a tall perennial plant about a meter high [9, 11], a hardy
herb or undershrub attaining a height of 1.8 m [8].
Flower: These are in axillary racemes or heads, 1 cm long [9],
are small, light violet in colour [11] or lavender to violet in
color and papilionaceous [8].
Seed: Seeds are 2-5, reniform, flat and deep grey [8].
Root: They are sweet in taste [9], thick, having many branches
with red or lemon color outside or yellowish or pale yellow
inside [8]. The underground part in some varieties consists of a
rootstock with a number of long, branched stem, in others, the
rootstock which is stout, throws off a large number of
perennial roots [5].
Leaf: These are odd pinnate in 4-7 pairs [9] and are
imparipinnate, ovate-lanceolate, smooth [8], and are multi
foliate [5].
Pods: Oblong to linear 1-3 cm long, flattened, straight in
more or less densely echinate, glandular [9].
Fruits: Fruits are 1-3 cm long, flat, covered all over the small
spinous outgrowths [11], fruits in August [8].
Vernaculars
The plant is known by different vernacular names in different
language, areas and traditions: Aslussiesa (Arab); Makk, Sus
(Afghanistan); Muraithi (Behar); Jashtimadhu, Jaishbomadhu
(Bengali); Jashtimadhu (Bombay); Noekhiyu, Noekhiyuanu
(Burma); Kan Ts’ao (Chinese); Lakris (Danish); Meethi lakdi
(Deccan); Zoethout (Dutch); Liquorice/Licorice (English);
Boisdoux (France); Liccarissa, Recanicu, Rigolicia (Genoa);
Lackrizen, Suessholz (German); Jethi Madha (Gujrati);
Mulhatti, Jethimadhu (Hindi); Malkhuzi, Malkhuzzi
(Hindubagh); Cam thao (Indo-China); Liquirizia, Legorizia,
Regolizia (Italian); Yashtimadhuka, Atimadhura (Kannad);
Kam chow (Malaya); Iratimadhuram (Malyalam);
Jeshtamadhu (Marathi); Liqiruizia (Naples); Muleti (North
western provinces); Lakris (Norwegian); Jatimadhu (Oriya);
Bikhe-Mahak (Persian); Lakrycya (Polish); Alacuz, Regoliz
(Portuguese); Alasus, Jetimadh, Muleti (Punjab); Khwazha,
Malkhuzi (Quetta); Dubez solotkoi (Russian); Madhuka,
Yashtimadhu (Sanskrit); Aregolizia (Sardinia); Gurigulizia,
Legmo dolce (Sicily); Athimadhuram (Siddha); Orozuz, Palo
dulce, Regaliza (Spanish); Lakritz (Swedish); Atimadhuram
(Tamil); Ashtimadhukam, Atimadhuramu (Telgu); Meyan
(Turkish) and Asl-us-Soos (Unani) [5, 7, 12-13].
Classification
Kingdom: Plantae
Division: Angiospermae
Class: Dicotyledoneae
Order: Rosales
Family: Leguminosae
Genus: Glycyrrhiza
Species: Glabra Linn
Part used
The dried, peeled or unpeeled underground stems and roots
constitute the drug, known in the trade as liquorice [5].
Mizaj (Temperament)
Unani physicians described the Mizaj of Aslus Soos as Hot
and Dry in second degree [11], according to Avicenna it is
neutral in all four temperament and according to Karmani it is
Murakkabul-Quwa (having compound action) [14], while some
others categorized in Hot in 2nd degree and Dry in 1st degree
[15, 16].
Dose
3-5 gm [7]
Afaal (Actions)
In classical Unani literature, various actions of the drug Aslus
Soos (Glycyrrhiza glabra) have been described such as
Munzij-e-akhlat-e-ghaliza (concoctus of viscous humour) [15,

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17-19], musakkin, gasil azae batni (abluent of internal organs),
muqawwi (tonic), kasir-e-riyah (carminative) [18], mundamil-
e-qarooh (wound healer), mulattif, munzij-e-balgham
(concoctive of phlegm) [17], muhallil-e-riyah (flatulence
dissolvent) [14, 15,19], jali (detergent) and mulayyin (laxative) [14,
18], maullid mani (semen productive) and mushtahi (appetizer)
[14] munaqqui-e-sadr wa reya, musaffi aawaz (voice purifier)
[19], mudir bol wa haiz (diuretic & emmenogouge) [14, 15, 18],
musakkin atash (thirst allaying) [14, 15, 18-19], muqawwi aasab
(nervine tonic) [15, 18-19], munaffis-e-balgham (expectorant) [17,
18], dafe tap-e-muzmena (antipyretic for chronic fever) [15, 18].
Istemal (Uses)
It gives strength to nerves. It is helpful in flatulence, asthma,
lung diseases, piles, chronic fever, thirst [14, 15], reduces cough.
It is beneficial in diseases of brain and nerves and useful in
palpitation. It is used in nausea, vomiting, and fasaad-e-safra.
Its decoction is used to improve vision power [14].
It is beneficial in sore throat, hoarseness of voice. It is useful
in burning micturition, gonorrhea, qurooh-e-masaana wa
gurda. It is also used in liver and spleen diseases. It relieves
nervine pain [19].
Muzir (Adverse effect)
It has adverse effect on kidney and spleen [15]. It also leads to
fluid retention [6].
Musleh (Corrective)
Katira (gum of Cochlospermum religiosum), Gule Surkh
(Rosa daemascena Mill) [19], Unnab (Ziziphus jujuba) [16] are
used as corrective for kidney, while Gule Surkh (Rosa
dascemena) for spleen [15].
Badal (Substitute)
Katira is used as substitute [19].
Pharmacological action
(As described in ethnobotanical and traditional literature)
The drug Glycyrrhiza glabra is described in detail in
ethnobotanical and scientific literature and various actions
have been reported to possess by it. Some pharmacological
actions and therapeutic uses are as follows:
Laxative, demulcent [5, 10], cooling effect, diuretic [10], tonic,
expectorant [5, 9-10], sedative, deobstruent [9], anti-
inflammatory, anti-ulcerous, anti-viral [20] and emmenogouge
[6].
Therapeutic uses
It is used for allaying coughs and catarrhal affections. It is
also useful in irritable conditions of the mucous membranes
of urinary organs. Extract is a constituent of cough syrups,
throat lozenges and pastilles and it is employed in the form of
aromatic syrups and elixirs for masking the taste of nauseous
medicines. The extract is reported to exert a healing effect on
gastric ulcers, is also reported to be useful in treatment of
Addison, S disease. Externally liquorice is applied with ghee
and honey for cuts and wounds [5].
Root is used in scorpion sting. Root in infusion, decoction,
extracts or lozenge is useful in inflammatory affection or
irritable conditions of bronchial tubes, bowels and catarrh of
the genito-urinary passages as cough, hoarseness, sore throat,
asthma, dysuria etc. it is also used as a slight laxative.
Inspissated juice is an ingredient of various laxative powders,
cough syrups, confections, lozenges, pastilles etc. Root mixed
with lime juice and linseed makes a homely valuable remedy
for coughs and cold, feverishness, pain, distress of breathing
and to ally thirst [10]. It is used in cough, fever, and paralysis
[9]. Oral doses of liquorice can be used for gastric, duodenal
and esophageal ulceration or inflammation, heartburn and
mouth ulcers. It is used for the treatment of asthma, acute and
chronic bronchitis and chronic cough. Liquorice is a mild
anti-inflammatory drug for arthritis and rheumatism [6]. Oral
liquorice preparations are used in the treatment of viral
infections (common cold, viral hepatitis, HIV, AIDS),
premenstrual syndrome, inflammations, and as a sweetening
agent. DGL is used in ulcerative conditions of gastro-
intestinal tracts. Topical preparations are used in eczema,
herpes and psoriasis [7]. Powder of root is prescribed in
coughs, hoarseness and in respiratory troubles. Infusions,
decoctions, or extract is laxative and a useful medicine in
urinary diseases, bronchial and gastric troubles [8].
Phyto-chemistry
It contains many organic as well as inorganic constituent that
are as follows:
Organic: Steroid, Tarpenoids, Resins, Flavonoids,
Carbohydrate, Starch, Proteins, Saponin [9].
Inorganic: Iron, atrontium, calcium, magnesium, potassium
and sodium [9].
The major constituents are triterpine saponins. Glycyrrhizin
(glycyrrhizic acid/glycyrrhizinic acid) is the major component
(2-9%). Other constituents are flavonoids (isoflavones:
liquiritin, isoliquiritin, formononetin), polysaccharides,
sterols, coumarins, asparagine [7]. The principle constituent of
liquorice to which it owes its characteristic sweet taste is
glycyrrhizin which is present in different varieties in a
concentration of 2-14%. Other constituent present in liquorice
are glucose (up to 3.8%), sucrose (2.4-6.5%), mannite starch
(c.30%), asparagine, bitter principles, resins (2-4%), a volatile
oil (0.03-0.035%) and coloring matter. The yellow color is
due to the anthoxanthin glycoside, isoliquiritin which
undergoes partial conversion to liquiritin. Both isoliquiritin
and liquiritin are bitter with a sweet after taste. A steroid
estrogen (possibly sterol) is also reported to be present in
liquorice. Glycyrrhizin occurs in liquorice as the calcium or
potassium salt of the trihydroxy acid, glycyrrhizic acid [5].
Roots contain a flavonoside, liquiritoside of low toxicity
which depresses smooth muscle action. Liquiritigenine
chalcone of spasmolytic properties is found in the plant [21].
The root also contains glycyrrhizin, saponin, flavon,
isoflavones, coumarins, glabridin, glabrene, glabrol,
glycyrrhizic acid [20].
Identity, purity, strength and assay
Ash values (%)
Total ash: 0.82
Water soluble ash: 0.26
Acid insoluble ash: 0.32
Loss on drying at 105 oC: 7.47%
Solid contents: 50.12%
Successive extractive value %
Pet ether (60-800): 0.12
Chloroform: 0.33
Acetone: 0.43
Ethanol: 13.15
Distilled water: 47.17
Pharmacological studies
A number of studies have been carried out on Glycyrrhiza
glabra in recent decades revealing that it possesses a lot of

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different pharmacological actions. Some of the important
pharmacological effects are as follows:
Antibacterial
In a study Anti-bacterial activity of Glycyrrhiza glabra was
determines by using disc diffusion methods. Because of the
presence of secondary metabolites such as; saponins,
alkaloids, flavonoids in hydro-methanolic root extract of
Glycyrrhiza glabra, the extract exhibits potent antibacterial
activity against both gram positive and gram negative bacteria
[22].
Anticancer
G. glabra extract has been used in herbal formulations for
combating cancers like PC-SPES, a polyherbal composition
used for prostate cancer. The licorice extract induced the Bcl2
phosphorylation and G2/M cycle arrest in tumour cell lines as
done by clinically used antimicrotubule agent Paclitaxel. 1-(2,
4- dihydroxyphenyl) -3-hydoxy- 3-(4’-hydroxyphenyl)1-
propanone (β-hydroxy-DHP) was identified in the licorice
extract, which induced Bcl2 phosphorylation in breast and
prostate tumour cells, G2/M cell cycle arrest, apoptosis
demonstrated by Annexin V and TUNEL assay, decreased
cell viability demonstrated by tetrazolium (MTT) assay, and
altered microtubule structure 44. 70% Methanol soluble
fraction of licorice acetone extract was found to induce
apoptosis in human monoblastic leukaemia U937 cells [23].
Anticoagulant
In a study Glycyrrhizin isolated from Glycerrhiza glabera
was identified as inhibitor of thrombin. It is found to prolong
the thrombin and fibrinogen clotting time. It also increases
plasma recalcification duration. Glycyrrhizin causes inhibition
in thrombin induced platelet aggregation. But there was no
effect of glycyrrhizin on Platelet Aggregating Factor (PAF)
and Collagen induced agglutination [24].
Antifungal
Methanolic extract of liquorice was reported to have
fungicidal activity against Arthrinium sacchari M001 and
Chaetomium funicola M002. Glabridin was found to be the
active compound giving anti-fungal activity [25].
Antihyperglycemic
A study was carried out to evaluate the anti-hyperglycemic
effects of 18 β- glycerrhetinic acid, aglycone of glycyrrhizin,
on streptozotocin-diabetic rats. Diabetes was induced in adult
male albino rats of the Wistar strain, weighing 180-200 g, by
administration of streptozotocin (40 mg/kg of body weight)
intraperitoneally. Diabetic rats showed increase of plasma
glucose and glycosylated haemoglobin (HbA1c) and a
decrease of plasma insulin and haemoglobin (Hb). Activities
of gluconeogenic enzymes such as glucose 6- phosphatase,
fructose 1, 6-biphosphatase increased and glucokinase,
glucode 6-phosphate dehydrogenase decreased in the liver
along with glycogen. Oral administration of 18β-
glycerrhetinic acid (50, 100, or 200 mg/kg of body weight) or
glibenclamide (600 µgm/kg of body weight) in 5% dimethyl
sulfoxide, for 45 days, prevented the above changes and
improved towards normalcy [26].
Anti-inflammatory
It is reported that glycyrrhetinic acid in liquorice extract gives
anti-inflammatory effect similar to glucocorticoids and
mineralocorticoids. Carbenoxolone (Biogastron), a
glycyrrhetinic acid analog, is reported to inhibit two enzymes
that are important in metabolism of prostaglandin, 15-
hydroxyprostaglandin dehydrogenase and Δ13 prostaglandin
thereby raising prostaglandin levels. Prostaglandins stimulate
mucous secretion and cell proliferation. Thus, ulcer healing is
promoted [27].
Antimalarial
Licochalcone A (a chalcone) present in liquorice has reported
to possess very good antimalarial activity. All Glycyrrhiza
species have this compound in different amounts and it can be
isolated from them. In vivo studies against P. yoelii in mice
with oral doses of 1000 mg kg-1 have shown to eradicate
malarial parasite completely. Also no toxicity was observed
[28].
Antioxidant
In a study antioxidant activity of liquorice flavonoids was
found to be over 100 times stronger than that of antioxidant
activity of vitamin E. A dose of 2.58 mg/ml liquorice
flavonoids can scavenge more free radicals (20.6%
scavenging) than 258 mg/ml of vitamin E (11.2%
scavenging). It has been reported that flavonoids from
liquorice are currently the strongest natural antioxidants
known [29].
Antitussive and expectorant
Glycyrrhizin is responsible for demulcent action of liquorice.
Liquiritin apioside, is an active compound present in the
methanolic extract of liquorice which inhibits capsaicin
induced cough [30]. Ethanolic extract of G. glabra was found
to be responsible for inhibition of 35.62% SO2 gas induced
cough in experimental animals (mice) [31].
Antiulcer
Liquorice can raise the concentration of prostaglandins in the
digestive system that promote mucus secretion from the
stomach; it was also reported that liquorice prolongs the life
span of surface cells in the stomach and has an anti-pepsin
effect [32].
Antiviral
The outbreak of SARS warrants the search for antiviral
compounds to treat the disease. At present, no specific
treatment has been identified for SARS-associated
coronavirus infection. We assessed the antiviral potential of
ribavirin, 6-azauridine, pyrazofurin, mycophenolic acid, and
glycyrrhizin against two clinical isolates of coronavirus
(FFM-1 and FFM-2) from patients with SARS. Of all the
compounds, glycyrrhizin was the most active in inhibiting
replication of the SARS-associated virus. The findings
suggested that glycyrrhizin should be assessed for treatment
of SARS [33].
Hepatoprotective
Glycyrrhizin induced a significant reduction in serum
aminotransferases and improved the liver histology when
compared with the placebo. It has also been implicated that
long-term usage of glycyrrhizin prevents development of
hepatocellular carcinoma in chronic hepatitis C. In vitro
studies have indicated that glycyrrhizin modifies the
intracellular transport and up presses hepatitis B virus (HBV)
surface antigen (HbsAg) [34, 35].

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It has been found that 18β-glycyrrhetinic acid (GA), an
aglycone of glycyrrhizin decreases the expression of P450 E1
thereby protecting the liver [36].
Immunomodulator
Polysaccharide fractions obtained from glycyrrhiza glabra
stimulate macrophages and hence elevate and assist immune
stimulation [37]. Also animal studies have revealed its efficacy
against the influenza a virus that is mediated by stopping the
virus replication. Glycyrrhizic acid present in the plant
inhibits virus growth and inactivates virus particles is a
potential source of immunomodulator [38].
Memory enhancing
The effects of Glycyrrhiza glabra on learning and memory
was investigated in mice. Elevated plus-maze and passive
avoidance paradigm were used to test learning and memory.
Three doses of aqueous extract of liquorice were administered
(75, 150 and 300 mg/kg p.o.). The study was conducted for 7
successive days in separate groups of animals. Significant
improvement in learning and memory of mice was reported at
the dose of 150 mg/kg. But, the exact mechanism of action is
unknown and needs further investigation [39].
Skin lightening
In vitro tyrosinase enzyme inhibition studies has showed that
21.2 μg/ml of methanolic extract of liquorice caused 50%
tyrosinase enzyme inhibition. The inhibition of tyrosinase
enzyme and reduction in enzyme activity is caused due to
modification of action site of the enzyme. Due to good
tyrosinase inhibition activity, liquorice extract can be used to
formulate cosmetic formulations with depigmenting activity
[40].
Conclusion
Glycyrrhiza glabra Linn (Mulethi) is a common ingredient in
many Unani compound formulations and has been in use
since times immemorial to treat wide range of indications. It
has been subjected to quite extensive phytochemical,
experimental and clinical investigations. Experimental studies
have demonstrated its antibacterial, anticancer, anticoagulant,
antifungal, anti-hyperglycemic, anti-inflammatory,
antimalarial, antioxidant, antitussive and expectorant,
antiulcer, antiviral, hepatoprotective, immunomodulator,
memory enhancing and skin lightening effects. The scientific
studies have proved most of the claims of traditional
medicines. These results are very encouraging and indicate
this drug should be studied more extensively to confirm other
potential therapeutic effects. Clinical trials using Mulethi for a
variety of conditions should also be conducted to use it
judiciously and cautiously in Unani as well as other systems
of medicine.
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