Saponin Glycosides- "Sapo" is Latin name for soap (soap-like)

-Group of organic compounds that form persistent froth when shaken with water even in dilute solution.

-Saponins cause haemolysis of red blood cells.

Properties:• - Soluble in water, alcohol and mixture of them.• Form persistent froth with water.• - Used as detergent (surfactant) and emulsifying

agents.• - Aglycones are called Sapogenin (acid hydrolysis).• - Cause haemolysis of RBC’s if reach the blood

(injection).• - Only small part absorbed when taken orally.• - Enhance the absorption of other drugs.

• - Form precipitate with Ba(OH)2-

Classification of saponins:• According to the nature of the aglycone saponins are

classified into Steroidal and Triterpenoidal saponins.• According to sugar: monodesmoside (one sugar

chain), Bidesmoside (two sugar chains)

HOHO

Triterpenoidal SapogeninSteroidal Sapogenin

1

3

1117

21

20

10

18

19

20

1811

28

2423

C

E

AA

D

13

14

B

3029

57

14

1

3

D26

27

17

25

19

12

5

8

22

24

25

26

27

B7

sugars sugars

sugars

sugars

cholesterol with 5,6-double bond

Steroidal Sapogenins

Dioscorea tubers

( Yam)

-Less distributed in nature compared to triterp.

saponins (found in Monocots, Dioscoraceace& Liliaceae).

- They are C-27 sterol with modified side chain .

• - They have spiroketal at C-22, sugars at C-3±C-26

• - Used mainly as precursors for the partial synthesis of sex hormones and corticosteroids.

• - Drugs containing Steroidal saponins such as:

– Dioscorea tubers Dioscin

– Sarsaparilla Roots Sarsaponin

HO

Sarsapogenin

1

3

1117

21

20

10

18

19C

A

D

57

14

22

B

O

O

16

23

24

25

2627

(Spiroketal at C-22)

DiosgeninThe same with 5,6- unsaturation

-

Examples of steroidal sapogenins

Spiroketal

O

O

H H

H

Progesterone

microbes

• Sarsapogenin is obtained by hydrolysis of saponins of Sarsaparilla roots (Smilax sp, Liliaceae). The drug is used for manufacture of non-alcoholic drink and stimulant (aglycones not hemolytic).

• Diosgenin is obtained by hydrolysis and fermentation of Dioscorea tubers (Yam, Dioscoraceae) and used for synthesis of sex hormones & steroids using appropriate

microbes.

- Very common in Dicot plants - Contain 30 carbon atoms- Ginseng: ginsenosides, panaxosides,…. - Horse chestnut seed: aescin - Liquorice root: glycyrrhizin - Senega: senegins

Triterpenoidal Triterpenoidal SaponinsSaponins

Nature: They are C-30 compounds but they have a typical Steroidal skeleton.Sources:

a) Panax ginseng (Korean ginseng)b) Panax quinquefolium (American ginseng).

c) Elutherococcus senticosus (Siberian ginseng)

OH

Sug-O

OH

Sug-O

O-Sug

Sug-OSug-O

Protopanaxdiols Protopanaxatriol

Uses og Ginseng:

• 1) It has an adaptogenic (anti-stress, anti-fatigue) effect.

• 2) It improves both physical and mental performance, including learning, memory and physical capabilities.

• 3) It improves the immune function and metabolism.

• 4) Improve liver function

• 5) Stabilize blood glucose and blood pressure.• -Korean Ginseng is superior to other types (steaming gives red

variety)

• -Siberian (Russian) not proved, contain lignans

Pentacyclic triterpenoid saponins

• -They are C-30 compounds.• -Much more distributed in nature.• -Have pentacyclic skeleton with 8 methyl

groups.

1- Horse Chestnut

• Source: Seeds of Aesculus hippocastanum (Hippocastanaceae)

• Contain mixture of triterpenoidal saponin mixture called “Aescins”

• It is used as:– Anti-inflammatory for bruises,

arthritis…..– Peripheral vascular disorders such as

Varicose veins (venous insufficiency) and Hemorrhoids.

2- Liquorice• Source: Glycyrrhiza glabra roots and underground stems.• Constituents: 10% triterpenoidal saponins (sweet)

“Glycyrrhizin”.K &Ca salts of glycyrrhizic acid with 2 molecules of D-glucuronic acid, flavonoids, bitter sub.

COO-

O

O

Glycyrrhetic acid

K+, Ca++

2 glucuronic acid

3

11

12

30-Hydrolysis produce glycyrrhetic

- acid-Glycyrrhizic acid (neutral form)

)1,2 linkage(

• Uses of liquorice:1) Flavoring agent, sweetener in Pharmaceutical

preparation.2) Demulcent and expectorant.3) Treatment of peptic ulcer, and gastritis4) Treatment of Rheumatoid arthritis and

Inflammatory conditions as it has cortisone like action, even hemorrhoids.

5) Treatment of liver diseases and hepatoprotective, antiviral.

6) Crude herb is a harmonizer in Chinese Herbal Medicine (CTM)

Side effects:Salt and water retention, elevation of blood pressure in

susceptible persons

3- Senega

• Source: Senega roots (Polygala senega, Polygalaceae).• Constituents: Triterpenoidal saponins “Senegin II”.

• Uses:– Stimulant expectorant in chronic bronchitis.

COOR

CH2OH

HO

RO

COOH

12

Aglycone (sapogenin) contain two carboxyl and one double bond at C-12

sugars

sugars

Senegins