Lec 10 Drugs Containing Saponin Glycosides(3)
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Transcript of Lec 10 Drugs Containing Saponin Glycosides(3)
Drugs Containing Saponin
glycosides
General Characters of Saponins
1. Widely distributed in higher plants.
2. Bitter, acrid taste & sternutatory (irritant to mucous
membranes).
3. Form colloidal solutions in H2O foam on shaking
lower of surface tension in aqueous solution.
4. Destroy RBCsblood haemolysis.
5. Toxic to cold- blood animals (fishes & frogs).
6. Toxic by i.v. injection & harmless by oral
route.
Chemical Characters
1. O-glycosides hydrolysis aglycone
(sapogenin) + sugar moiety.
2. Aglycone:
– triterpenoidal (C-30) [mainly in Dicotyledons]
– steroidal (C-27) [mainly in Monocotyledons]
3. Sugar moiety:
– Often contain uronic acids or acyl residues.
– Usually glycosylation is at C-3.
O
O
A B
C D
1
2
3
4
56
7
89
10
11
12
13
1425
21
22
19
15
16
1718
20
1
2
3
45
6
7
89
10
11
12
13
1415
16
17
18
19
2021
22
23 24
25
26
27
E
Steroidal saponin aglycone Triterpenoidal saponin aglycone
3029
Economical & Medicinal Importance
Economical uses
1. Cleaning industrial equipment & fine fabrics.
2. Powerful emulsifier.
3. Steroidal sapogenins used in semisynthesis of
cortisone & sex hormones.
Medicinal uses
1. Expectorant
2. Immunostimulant
3. Control of schistosomiasis snails (molluscicides)
4. Hypoglycemic.
Tests for Identification
1. Froth test:
1 ml of aqueous solution of saponin or plant
extract + shake persistent & voluminous
froth.
2. Haemolysis test:
Suspension of RBCs in normal saline + equal
volume of plant extract in normal saline +
shake gently clear red solution indicating
heamolysis of RBCs (compared with blank ).
Licorice Root
(RADIX GLYCYRRHIZAE)
العرقسوس -جذر السوس • Botanical origin: The dried peeled or
unpeeled roots and stolons of
Glycyrrhiza glabra L. and its
varieties (Family Leguminosae =
Fabaceae).
• Geographical Source: Licorice is
native to the Mideterranean region,
as Spain, Italy, England, France,
Germany, U.S.A. ,Russia and Egypt.
Licorice Powder
• Powdered licorice, is light yellow, having a faintcharacteristic odor and a very sweetish taste,.
Powdered licorice is characterised by:
• Numerous fragments of fibres accompanied bycrystal sheath.
• Dark yellow fragments of borded-pitted vessels .
• Prismatic crystals of calcium oxalate.
• Numerous starch granules, free or in parenchymacells, mostly simple, oval, round or fusiform, withno striations but occasionally showing hilum
• Cork may be present
Licorice
Active Constituents of Licorice
1- Saponins
Rhizomes & roots of licorice contains 2-6 % of the triterpenoidsaponin Glycyrrhizin
Glycyrrhizic acid = Glycoside of
Glycyrrhetic acid
HO
COOH
Glycyrrhetic acid(aglycone)
O
3
Glycyrrhizin = mixture of K+ & Ca++ salts of Glycyrrhizic acid
2-Major non-saponin constituents of
Licorice
Flavonoid glycosides: major liquiritin (flavanone).
Coumarins: herniarin & umbelliferone.
Others: asparagine, dihydrostigmasterol, glucose,
mannitol & starch.
Licorice - Uses1. Expectorant & demulcent by stimulation of tracheal mucous
secretion due to glycyrrhizin.
2. Antiinflamatory & adrenocorticotropic activity due to steroidal-like activity of glycyrrhizin &/or glycyrrhetic acid.
3. Antihepatotoxic, antibacterial, antirheumatic, antitumour &antiviral.
4. Used in treatment of gastric & duodenal ulcers by increasing therate of healing of gastric mucosa mainly due to liquiritin.
DGL = (Deglycyrrhizinated extract) licorice preparation with verylow % of glycyrrhizin (< 1 %) used as antiulcer for hypertensivepatients.
5. Used in laxative formulations.
6. Used as sweetener (glycyrrhizin 50 times > sweet than sucrose)& as flavoring agent to mask the bitter taste of some drugs asaloe, quinine & others.
ContraindicationsThe drug is contraindicated in patients with
hypertension, hypokalaemia, or chronic renal
insufficiency, and during pregnancy.
The drug should not be taken concurrently with
corticosteroid treatment.
Aldosterone-like effects: sodium and water retention,
potassium depletion, hypertension.
Side effects
Ginseng RootSource
Roots of Panax quinquefolius (Americanginseng) & P. ginseng (Asian ginseng),Araliaceae.
Contains a complex mixture of triterpenoidal
saponins with a tetracyclic ( steroids) orpentacyclic structure (in its cork).
Classification
Classified into 2 types:
1. Ginsenosides,
2. Panaxosides ( differ
from ginsenosides
in the sugar moiety).
Aerial partsRoots
Ginseng saponins
Ginsenosides:
1.Major saponins of ginseng (0.7-3 %
calculated as ginsenosides).
2.Aglycones of most ginsenosides have a
tetracyclic steroidal structure.
Ginsenosides
HOR2O
HO
CH3
O R1
HOR2O
R1O
CH3
20(S)-Protopanaxadiols 20(S)-Protopanaxatriols
Ginsenoside R1 R2
Rb1 -glc (2-1)glc -glc (6-1)glcRb2 -glc (2-1)glc -glc (6-1)arabRc -glc (2-1)glc -glc (2-1)arabRd -glc (2-1)glc -glc
Ginsenoside R1 R2
Re -glc (2-1)rha -glc Rf -glc (2-1)glc -HRg1 -glc -glc Rg2 -glc (2-1)rha -H
Ginseng -Therapeutic uses
1- Adaptogenic (antistress): enhances body nonspecific resistanceto external stress (physical, chemical or biological).
2- Improves physical & mental performance e.g. learning, memory& physical capabilities.
• Tonic, stimulant, diuretic & carminative.
• Improves immune function & metabolism.
• Used in anemia, Hepatoprotective (ginsenosides), diabetes(saponins and polysaccharides), insomnia, gastritis, Antitumor(polyacetylenes and polysaccharides) & sexual impotence.
6. Contraindicated in case of hypertension & during pregnancy.
Preparation
Ginseng is often processed in two forms:
-White ginseng (peeled).
-Red ginseng (unpeeled).
There are many types and grades ofginseng and ginseng extractsdepending on the source, age; andparts of the root used, and themethods of preparation
FENUGREEK SEEDالحلبة
• Dried ripe seeds of Trigonella Foenum-graecum (Fam.
Leguminosae).
• Powdered Fenugreek is characterized by its yellow color,
and its characteristic odor and mucilaginous bitter taste.
• Microscopically, it is characterized by:
– Fragments of the testa showing the palisade-
like cells and the basket-like cells of the
hypodermal layer.
– Fragments of mucilaginous endosperm cells.
– Fragments of the cotyledons with
parenchymatous cells containing fixed oil and
aleurone grains.
– Starch granules are small and very few.
Fenugreek powder
• Cuticle (c),
epidermis (ep.) and
hypodermis(h.) of
the testa in sectional
view.
• Epidermis of the
testa in surface
view.
• Hypodermis of the
testa in surface view
Active Constituents:• Neutral mucilage (28%) It gives blue color With
methylene blue, (neutral mucilage).
• Proteins and amino acids. Protein (23-25%)containing high quantities of lysine and tryptophan.Free amino acids, and a non essential amino acid 4-hydroxy isoleucine which has an insulin- stimulatingactivity .
• Biotin, choline, essential oil, folic acid, inositol, iron, and
lecithin.
• Fixed oil (6%).
• Saponins (diosgenin, gitogenin and tigogenin).
• Two alkaloids (trigonelline and choline).
• Vitamins (A, B1, B2, B3, B6, B12, and D).
Uses
• As lactagogue, demulcent and emollient.
• Laxative.
• For nutritive purposes.
• Source of diasogenin, a basic compound in
the semi-synthesis of steroid drugs such as
cortisone and sex hormones.
• Antidiabetic, cholesterol-lowering, anti-ulcer and
anti-cancer.
بذر أبو فروة Horse chestnut Seed
(Semen Hippocastani)
Names :Aesculus kernel
Origin :Horse chestnut is the dried and fresh kernel of
Aesculus hippocostanum L. Family Hippocastamaceae.
Constituents
-Saponin referred to as escin (which is a complex mixture
of over 30 individual pentacyclic triterpene diester
glycosides) is regarded as the main active constituent; α
and β-escin are the major glycosides.
-Flavones, caumarins and tannins are also present.
Horse-chestnut demonstrates anti-edema and anti-
inflammatory effects due to saponin content. Escin
stimulates the release of corticosteroids necessary for
the anti-inflammatory activity. Antioxidant,
hypoglycemic and cyto-toxic activities were also
reported and attributed to the saponin content of the
extract.
Uses
The flavonoids of the horse-chestnut leaves normalize
the pathologically increased permeability of blood
vessels and reduce the fragility of vessel walls, whereas
their coumarins content, being a vitamin K antagonist,
inhibits prothrombin production.
Horse-chestnut has been used for the treatment of
varicose veins, haemorrhoids, diarrhea, fever and
enlargement of the prostate gland.
DRUGS CONTAINING
FLAVONOID GLYCOSIDES
Flavonoids’ Chemistry
Variety of structural forms
Free aglycones or glycosides
Skeleton contains 15 carbon atoms:
C6-C3-C6 [2 phenyl rings linked by athree-carbon chain = diphenyl propanederivatives].
*** Flavonoids give yellow color withalkali as well as with aluminiumchloride.
Flavonoids-Chemistry
O
A
B
Ring A
Ring B
Pyran ring
O1
2
3
45
6
7
8 1'
2'
3'
4'
5'
6'
CH2
CH2
H2CA
B
Diphenyl propane skeleton
C6-C3-C6Flavonoid skeleton
Buchu Leaves
Origin of The Pant:
Buchu is the dired leaves of Barosma betulina
Family Rutaceae. Known as short buchu,
round buchu or diosma.
Origin of the name:
Buchu is a Zulu name of the drug. Barosma
refers to the heavy odor of the leaves.
Buchu Leaves
Constituents:
1. Crystalline rhamnoglycoside diosmin
(flavone glycoside),found as sphero-
crystals (in the epidermal cells) and
hesperidin.
2. Volatile oil which is contained in the
oil glands cotains up to 30%
diosphenol.
3. Mucilage which is deposited on the
inner walls of the epidermal cells.
O
OOH
OH
OMe
Rh1-6Glc-O
Rutinose
Diosmetin
Diosmin
7
Uses:
1- Disinfectant to urinary tract, excreted
by the kidney rendering the urine
antiseptic due to diosphenol.
2- Diuretic and Diaphoretic due to
diosphenol.
3-Diosmin is used to treat peripheral
vascular disorders (capillary fragility)
just like varicose veins and piles
(hemorrhoids).
Crataegus Fruits
(Fructus Crataegi, Hawthorn)
ديازعرور الو
Names: Hawthorn berry, Crataegus fruits, Fructus
oxycanthae
Origin: Hawthorn berry consists of the dried fruits of Crataegus monogynaJaq. ( = C. oxycantha L.), Family: Rosaceae.
Uses and Actions:
It has been claimed that preparations of hawthorn berry
have been applied to the treatment of :
•Early forms of cardiac insufficiency and angina pectoris.
•Nervous heart complications.
•Heart and circulatory disturbances.
•Hypotension, and atherosclerosis.
Constituents:
1- Oligomeric procyanidins (1-3%).
2- Flavonoids (1-2%) named: Hyperoside, vitexin 2-rhamnoside
and rutin.
3- Amines ( some with cardiotonic action).
4-Catechins and epicatechins.
5- Phenol-carboxylic acids (especially chlorogenic acid ).
Ginkgo Leaf
Ginkgo leaf consists of the dried leaf of Ginkgo biloba (Ginkgoaceae).
1- The major constituents are flavonoids of which mono-, di-, and tri-
glycosides and coumaric acid esters that are based on the flavonols
kaempferol and quercetin dominate.
Major chemical constituents
2- Diterpene lactones ginkgolides A, B, C, J, and M and the
sesquiterpene lactone bilobalide
Medicinal uses
Extracts have been used for symptomatic treatment of mild to moderate
cerebrovascular insufficiency (memory deficit, disturbance in concentration,
depressive emotional condition, dizziness, and headache)
1- Volatile oil.
2- More than 20 alkamides, mostly isobutylamides
3-Caffeic acid ester derivatives present include echinacoside,
cynarin, and chicoric acid.
4-Polysaccharides
Active constituents
Preparations of Echinaceae are administered orally in supportive
therapy for colds and infections of the respiratory and urinary tract.
Beneficial effects in the treatment of these infections are generally
thought to be brought about by stimulation of the immune response
Medicinal uses:
Echinacea
Echinaceae consists of the fresh or dried roots
or whole herb of Echinacea angustifolia or,
E.purpurea or E. pallida (Asteraceae).
Drugs containing Cyanogenic
(Cyanogenetic or Cyanophore)
glycosides
Cyanogenic glycosides
( Cyanogenetic or Cyanophore glycosides)
-hydroxynitrile derivatives = cyanohydrins.
Fairly unstable, stabilized by -D-linked sugar chains with -D-glucose as first
sugar attached to the aglycone.
O-glycosides hydrolysis HCN gas.
Examples (Linseed & Bitter almond seed)
C
R2sugar-O
R1
CN
General structure of cyanogenic glycosides
• Names: Linseed,
Flax Seed
• Origin: Linseed is
the dried ripe
seeds of LinumusitatissimumFamily: Linaceae.
Linseed بذر الكتان
Constituents• 30 to 40% of fixed oil. The oil is rich in
unsaturated fatty acids : oleic acid (39%),
linoleic acid (15%) and a-linolenic acid (30-
60%).
Linoleic acid ( Omega-6- fatty acid), and
linolenic acid (Omega-3 fatty acids) are
essential fatty acids.
• 25% of protein.
• 3-6% of mucilage
• Small amount of a cyanogenic glycoside
(linamarin).
• Unripe seeds contain starch but the ripe seeds
are free from starch.
Uses and actions• In folk medicine, decoction as demulcent in
acute or chronic gastritis.
• Omega-3 fatty acids are anti-inflammatory.
Thus, used in rheumatoid arthritis and
psoriasis. They cause a significant reduction
of very low density lipoprotein (VLDL), and
low density lipoprotein (LDL). They may be
used to reduce the blood pressure,
especially in hypercholesterolaemia and
hypertension. They offer protection against
angina and thrombosis as they reduce the
blood viscosity.
• Cake is used in poultices for boils and
carbuncles.
• As a laxative in habitual constipation, due to
its mucilage. (crushed seeds). The laxative
action is due to increase in the volume of the
intestinal bowel contents and stimulation of
peristalsis (bulk laxative).
• Linseed is used as antitussive due to its
cyanogenic glycoside content.
Toxicity:
• Linseed is advisable with plenty of fluids
otherwise it may cause flatulence.
• Liberation of HCN.
What’s the economic and
commercial importance of linseed
plant and seeds?
Chemical tests
• Test for Cyanogenic glycosides:
(Guignard’s paper test):
Crushed seeds in test tube moistened
with water covered with a piece of
cork having a sodium picrate paper
(yellow color), leave in a warm place
for 30 min., HCN will be evolved
converting the yellow colored paper to
brick red color.
H3C
CH3
C
O
CN
Glc
Linamarin
Bitter almond seeds بذر اللوز المر
SourceKernels of bitter almond seeds (Prunus amygdalus var.
amara) , [Rosaceae] .
Constituent:The kernel contains mainly Cyanogenic glycoside named
as Amygdalin
HydrolysisAmygdalin + emulsin enzyme benzaldehyde +HCN +
2 glucose.
UsesPreparation of benzaldehyde (volatile oil of bitter
almond) which is used as sedative and
flavoring agent.
Peaches
Kernels of apricots
Amygdalin-hydrolysis C
O
CN
Glc-(1 - 6)-Glc
H
(gentiobiose)
Amygdalin
CO
CN
Glc-(1 - 6)-Glc
CO
CN
Glc
C
HO
CNCHO
HCN
+ Glucose
Mandelonitrile
PrunasinAmygdalin
Benzaldehyde
hydrolyase
Prunasin hydrolyase
Mandelonitrile lyase
H
H H
(Gentiobiose)
Amygdalin
+ Glucose+
(Volatile oil of bitter almond)
Bitter almond
Drugs containing Glycosinolates
(containing sulphor and
nitrogen)
Drugs containing glycosinolates
• Black mustard seeds (Brassica nigra, containing sinigrin glycoside).
• White mustard seeds ( Brassica alba,containing sinalbin glycoside).
• The two drugs are mentioned under drugs
containing volatile oils as sinigrin glycoside
on hydrolysis gives the volatile oil
allylisothiocyanate.