SAPONINS
SAPONINS
Definition of saponins Classification of saponins Distribution, localization and function Uses Physical characters Methods of preparation Quality control Storage Chemistry Saponins containing drugs from medicinal plants and
their medical uses
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Learning Objectives
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The student should be able to cover
Definition and structure of saponins and glycosides drugs.
Extraction, characterization and quantification of saponins
drugs.
Structural and biological properties of saponins drugs.
Official names, synonyms, biological sources,
identification, chemical constituents, uses, precautions,
adverse reactions, contraindications and toxicity of some
selected drug containing saponins.
Learning Outcomes
4
Pharmacognosy by W.C. Evans. Trease and Evan’s, 12th edition.
London. Page Number 23-153; 170-205; 250-289.
Pharmacognosy Phytochemistry by Jean Bruneton, Medicinal Plants
(1999) Page Number 5-73; 91-256; 312-345
Pharmacognosy and Pharmacobiotechnology (1996) by Page
Number 1-40; 59-121.
Phytochemical Methods, J. Harborne PDR for Herbal Medicines
2nd edition 30-75; 77-156.
Organic Chemistry by IL Finar Page Number 368-473; 170-205;
250-289
References
Saponins are a class of chemical compounds, one of many
secondary metabolites found in natural sources
Saponins found in particular abundance in various plant species.
They are amphipathic glycosides grouped, in terms of
phenomenology, by the soap-like foaming they produce when
shaken in aqueous solutions
In terms of structure, by their composition of one or more
hydrophilic glycoside moieties combined with a lipophilic
triterpene derivative.
Saponins
Saponins
Plant constituent which bring about frothing in an aqueous
solution. Historically it is used for their detergent
properties.
Saponins is one type of glycosides
Saponins have haemolytic properties when injected into
the blood stream are highly toxic (used as an arrow
poisons).
When taken orally, saponins are harmless.
Two types of saponins are recognized
Pentacyclic triterpenoid Steroidal types.
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Saponins
Group of organic compounds that form persistent froth when shaken with water.
Saponins cause haemolysis of red blood cells.
The word Soap means Soap like.
Saponin Glycosides
Soluble in water, alcohol and mixture of
them.
Form persistent froth with water.
Used as detergent and emulsifying agents.
Aglycones are called Sapogenin.
Cause haemolysis of RBC’s if reach the
blood.
Form complex with cholesterol.
Only small part absorbed when taken orally.
Enhance the absorption of other drugs. 21-Jan-
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Properties
Saponins are hydrolyzed (by acids) to give an aglycone and
different sugars related to uronic acids.
Saponin Aglycone + Sugar
Aglycone called sapogenin (insoluble in water).
Structure of the sapogenin (aglycone) determines the type of
saponin (steroidal or tetracyclic triterpenoid and pentacyclic
types).
Both types of glycosides have a glycosidal linkage at C-3.
Both types of saponins have a common biogenic origin
(mevalonic acid and isoprenoid units)
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Saponins = Glycosides
Rare in monocotyledons
But abundant in dicotyledons.
Sapogenin is attached to a chain of sugar or uronic acid
units (or both) often in the C-3 position.
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Pentacyclic Triterpenoid Saponins
It is also called tetracyclic
triterpenoids
Found in many monocotyledons such as
Wild yam (Dioscorea vilosa).
Also found in dicotyledons fenugreek.
Strophanthus and Digitalis contain both
steroidal saponins (glycosides) and
cardiac glycosides.
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Steroidal Saponins
Generate much interest due to their
relationship with compounds such as
sex hormones, cortisone, diuretic
steroids, vitamin D and the cardiac
glycosides.
Some are used as starting materials
for the synthesis of these
compounds.
Diosgenin is the main sapogenin used
by industry . 21-Jan-
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Significance of Saponins
Test for Saponin Glycosides
Froth Test -Place 1ml solution of drug in water in a semi-micro tube and shaken well and noted for a stable froth.
Hemolysis test -Add 0.2ml solution of saponin (prepared in 1% normal saline) to 0.2ml of v/v blood in normal saline and mix well, centrifuge and note the red supernatant compare with control tube containing 0.2ml of 10% blood in normal saline diluted with 0.2ml of normal saline.
Normally maceration method is use for the extraction of saponins.
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Extraction of saponins
Water +Methanol
Plant materials
48 hours
Filter
Saponins
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Acetyl Co-Acetate (Acctyl-coA)
Hydromethylglycol-Co-acetate (HMG-CoA)
Mevalonic acid
Isopentenyl pyrophosphate (IPP)
Dimethylallyl pyrophophate (DMAPP)
Meva
lonic acid
path
way
. Gernyl pyrophosphate (GPP) Squalene
Steroidal Saponins
Biogenesis of Steroidal Saponins
OPPOPP
OPP
Mevalonic acid
Hemiterpenes (C5) DMAPP (C5) IPP (C5)
GPP (C10) Monoterpens & Iridoids (C10)
IPP
OPPFPP (C15) Sesquiterpenes (C15)
IPP
OPPGGPP (C20)
Diterpenes (C20)
2 x FPP Triterpenes (C30) 2 x GGPP Tetraterpens (C40)
Steroids (C18-C30)
squalene
Natural products serve as starting points for the partial
synthesis of commercial products.
Cortisone is synthesized from Hecogenin.
Sex horomones (oral contraceptives)–synthesized from
diosgenin.
Diosgenin can also be used to make corticosteriods.
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Natural Steroids for the Production of Pharmaceuticals
Corticosteriods
◊ Definition: Wild yam is
the underground roots and
tubers of Dioscorea
villosa.
◊ There is no suggestion
that the plant was used as
a contraceptive in the
past. Traditionally been
used to treat menstrual,
ovarian & labour pains. 21-Jan-
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Dioscorea villosa-Dioscoreaceae
Dioscorea villosa – Wild Yam
Steroidal saponins (mainly
dioscin)
Phytosterol,alkaloids,tannin
s, starch.
Actions
Anti-spasmodic anti-inflammatory anti-rheumatic Diaphoretic diuretic, qi tonic expectorant
In Zulu traditions, wild yam is
used to treat convulsions, epilepsy
and hysteria.
Also used for colic, dry cough,
depression, diarrhoea, diabetes,
emotional weakness, immune
weakness, IBS, leg pain, low
sperm count, lung weakness,
morning sickness, neuralgia, night
sweats, RA, senility,
spermatorrhoea, threatened
miscarriage.
Topically: salve for eczema,
poultice for bruises and scabies.
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Dioscorea villosa-Dioscoreaceae Constituents Other uses
Definition: Siberian ginseng
consists of the dried roots
and rhizomes of
Eleutherococcus senticosus.
This herb is better at
maintaining good health
rather than treating illness.
Traditionally been used to
treat Insomnia
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Eleutherococcus senticosus-Aralaiceae
Constituents
Triterpenoid saponins
Glycans
Polysaccharides
Coumarins
Lignins
Actions
Adaptogen
Tonic
Immune-modulator
Uses
Insomnia
Stress
Surgery Recovery
Chemotherapy patients
Cardiovascular disease
CONTRA-INDICATIONS
Continuous use
Hypertensive patients
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Siberian Ginseng –Eleuthrococcus
Definition: Ginseng consists
of the dried or fresh roots
of Panax ginseng. Also
called Korean or Asian
ginseng.
Traditionally it is used for
the treatment of appetite
loss
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Ginseng–Panax ginseng
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Medicinal Uses To Improve stamina, reaction
time, decrease high cholesterol.
Speeds up recovery time after
illness, childbirth and surgery.
Aids, Alzheimer’s, anaemia,
appetite loss, chronic fatigue,
depression, infertility, memory
loss, tacchycardia, PTSS.
Helps soften skin–anti-wrinkle
products.
Active Constituents:
Triterpenoid saponins
(ginsenosides), B vitamins,
selenium, phytosterols,
volatile oils.
Medicinal Actions:
Adaptogenic tonic, anti-
inflammatory, anti-oxidant,
anti-spasmodic, cardiotonic,
hepatoprotective, immune-
stimulant, nervine
Panax ginseng – Korean Ginseng
Leaves can be used for fever.
Effects – cumulative – work best
after a period of use, but should
not for excessive/continuous use.
Contraindications Should not be used if pregnant or
lactating.
Not to be used in cases of heat or
inflammation.
Should not be taken if suffering
from flu, fever, pneumonia,
constipation or hypertension. 21-Jan-
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Panax ginseng –Contraindications
Definition: Fenugreek consists of
the dried seeds of Trigonella
foenum-graecum.
Traditionally it is used for the
treatment of diabetes
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Trigonella foenum graecum– Fabaceae (Legume Family)
Active Constituents Steroidal saponins
(diosgenin, yamogenin), B
vitamins, alkaloids,
glycosides, flavonoids,
courmarin, mucilage.
NOTE: Should not be
used to treat diabetes
without professional
supervision.
Medicinal Actions
Anti-inflammatory, carminative,
antiseptic, emollient, expectorant,
hypoglycaemic, phytoeostrogenic.
Medicinal Uses
Stabilize blood glucose levels,
anorexia, catarrh, cough, sore
throat. Topically for boils, burns,
cellulitis, gargle for sore throats,
eyewash for inflammed eyes and a
facial wash.
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Fenugreek-Trigonella
Definition: Quillaja bark
consists of the dried inner
bark of Quillaja saponaria.
It is also called soup bark,
Quillaja or Panama wood.
Traditionally it is used for
emulsifying agent
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Quillaja saponaria –Rosaceae
Mixture of saponins (10%)
On hydrolysis: main
sapogenin Quillaic acid
and Gypsogenin.
Sapogenin Quillaic acid +
Gypsogenin
Also consists of sugars,
starch and calcium
oxalates.
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Quillaja Bark - Constituents
Used as an emulsifying agent.
It is used for the treatment
for various chest pain
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Quillaja Bark - Uses
Definition: Liquorice consists
of the dried unpeeled roots
and stems of Glycyrrhiza
glabra.
Traditionally it is used for
the treatment of ulcers
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Glycyrrhiza glabra - Leguminosae
Plants grow well in deep sandy, fertile soil.
The underground parts are collected in their 3rd-4th year.
Dug up & washed.
Some are peeled and cut shorter before drying; others are left unpeeled.
Imported in bales, or made into stick or block liquorice.
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Glycyrrhiza–Cultivation & Collection
Glycrrhizin – Responsible for the sweet taste.
Glycerrhizic acid – Triterpenoid saponin.
Flavonoids – Responsible for yellow colour.
Liquiritin – Chalcone responsible for yellow colour
Sugars (glucose and sucrose), protein & starch.
Glycyramarin – Bitter principles (mostly in outer tissue –removed in peeled varieties)
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Glycyrrhiza glabra -Constituents
Glycyrrhiza uralensis
Glycyrrhiza hirsutu
Glycyrrhiza echinata
Glycyrrhiza macedonia
Glycyrrhiza pallidiflora
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Glycyrrhiza glabra - Adulterants
Actions
Anti-microbial/anti-viral Anti-spasmodic Anti-Ulcerogenic Demulcent Expectorant
Uses
Flavouring agent RA Addison’s disease Inflammatory conditions Peptic ulcers
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Glycyrrhiza glabra Actions & Uses
Definition: Senega consists
of the dried rootstock and
root of Polygala senega.
Traditionally it is used for
the treatment of snake-
bite
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Polygala senega -Polygalaceae
Triterpenoid Saponins:
Main saponin – Senegin
Other saponins
Senegenin
Senegenic acid
Polygalic acid
Also contains
Sorbitol (sweet taste),
Sucrose,
Fat and
Sterols.
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Polygala senega – Constituents
White senega – Polygala alba
Southern senega –Polygala boykini
Pakistan senega –Glinus oppositifolius
Turkey senega – Polygala pruinosa
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Polygala senega - Adulterants
Actions
Stimulant expectorant
Uses
Chronic bronchitis
TRADITIONAL USES
First used by the Native American
Indians as a remedy for snake-bite.
It was later used by the English as
cure for pleurisy and pneumonia.
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Polygala senega - Uses
Definition: Gentian consists of
the dried, fermented roots and
rhizomes of the yellow gentian,
Gentiana lutea.
Traditionally it is used for
the treatment of Liver
disorders
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Genitana lutea - Gentianaceae
There is no demand for the unfermented ‘white’ gentian, all
commercial drugs consist of the fermented ‘red’ variety.
Herb is made into heaps, packed on a hillside and occasionally
covered with earth and left there for some time.
Washed and cut into slices.
Dried: Open air or oven.
When prepared this way, the herb becomes much darker in
colour (fermented), loses some of its bitterness and acquires a
distinctive odour. 40
Gentiana – Collection & Preparation
Main Chemical Constituents
Gentiopicroside
Gentiogenin
Other constituents
Glycosides
Alkaloids
Flavonoids
Sugars
Pectin and essential oil.
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Gentiana lutea - Constituents
Allied Drugs
Gentiana purpurea
Gentiana pannonica
Gentiana punctata
Gentiana kurroo
Picrohiza kurroo
Adulterants
Rumex alpinus
Veratrum album
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Gentiana lutea
Actions
Anti-microbial/anti-viral
Uses
Herbal tonic
Liver disorders
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Gentiana lutea - Uses
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