The document discusses four plants used in traditional Indian medicine to treat diabetes: Gymnema sylvestre, Salacia reticulata, Pterocarpus marsupium, and Swertia chirata. It describes the chemical constituents of each plant including major components like gymnemic acid, salacinol, and mangiferin. It also summarizes the proposed mechanisms of action for lowering blood glucose, such as inhibiting alpha-glucosidase enzymes and increasing insulin secretion. A brief overview of other medicinal uses and potential side effects is provided for each plant.

1. Active constituent of Drugs Used
in Diabetic Therapy
Subject: Chemistry Of Natural
Products
By: 17mph411
Sem: 1 MPharm

2. GYMNEMA SYLVESTRE
FAMILY: Asclepiadaceae.
COMMON NAMES: Gurmar, Dhuleti

3. CHEMICAL CONSTITUENTS:
o Alkaloids, organic acids
(5.5%),
parabin, calcium oxalate
(7.3%), cellulose (22%), lignin.
o Gymnema leaves consists of triterpene
saponin belonging to oleanane and
dammarene class.
o MAJOR COMPONENTS:
Gymnemic acid and gymnemasaponins
belong to oleanane class.
Gurmarin and gymnemasides belong to
dammarane saponins.
o OTHER COMPONENTS:
flavones, anthraquinone, hentriacotane and
pentatriacotane, resins, tartaric acid,
glcosides and stigmasterol.

4. Chemistry: The proposed structure of gymnemic acid
as D-glucuronide of hexahydroxy-triterpene
esterified with acids. ‘Gurmarin’ a 35 amino acid
peptide with 3 intramolecular disulphide bond is
obtained from gymnema leaves which suppresses the
neural response to sweet taste.

7. MECHANISM OF ACTION (GYMNEMIC ACID):
Gymnemic acid destroys the ability to discriminate the sweet taste. The
atomic arrangement of gymnemic acid is similar to glucose so they fill the
receptor location on the taste buds thus preventing the activation of sugar
molecule. It also occupies the receptor in the external layer of the intestine
thus decreasing the sugar concentration in the body.
1. Prompts regeneration of islet cells.
2. Increases secretion of insulin.
3. Inhibits the absorption of glucose from intestine.
4. Increases activity of enzymes utilising glucose by insulin dependant
pathway, which increases phosphorylase activity causing decrease in
gluconeogenic enzyme and sorbitol dehydrogenase activity.

8. OTHER USES
• Used in treatment of blood pressure and cardiac
rhythms.
• Decreasing Glycosylated haemoglobin Hb1AC.
• Used in glycosuria.
• Used in antiinflammatory, anti helminthes,
expectorant and snake bites.
• Lowering serum cholestrol and triglycerides.
• Used for weight loss.
SIDE EFFECTS:
• Hypoglycemic effects
• Neurological effects

9. Salacia Reticulate
Family: Hippocrateaceae.
Common Name: Saptarangi, Marking Nut Tree.

10. CHEMICAL CONSTITUENTS:
Salacinol, kotalanol, mangiferin

11.  Mangiferin (a xanthone) , 1,3-diketones, dulcitol and leucopelargonidin (a
linear iso-mer of natural rubber), iguesterin (quinonemethides), epi-
catechin, phlobatannin and glycosidal tannins, triterpenes, and 30-
hydroxy-20(30) dihydroi-soiguesterin, hydroxyferruginol, lambertic acid,
kotalagenin 16-acetate, 26-hydroxy-1,3-friedelanedione, maytenfolic acid .
OTHER CONSTITUENTS:
Mechanism:
Stems and roots of Salacia contain potent alpha-glucosidase inhibitors (salacinol and
kotalanol). Salacinol and kotalanol competitively bind to alpha-glucosidase present in
the brush borders of small intestine and prevent the breakdown of oligosaccharides
into monosaccharides and thus, maintain the normal blood levels in the human body.
The sugar‐based sulfonium sulfates salicinol, ponkoranol, kotalanol, and salaprinol are
believed to be major contributors to the anti‐diabetogenic effects of Salacia species.
Mangiferin (a xanthone) is also present in S. reticulata and other Salacia species and
has been shown to be an inhibitor of sucrase, isomaltase (α‐glucosidases), and aldose
reductase activities.

12. Other uses:
Used as anti inflammatory.
Treatment of asthama.
Amenorrhea.
Dysmenorrhea.
Rheumatism.
Side Effects:
Belching
Pain in the abdomen
Nausea
Diarrhoea

13. Pterocarpus marsupium
Common Name: Malabar kino, Indian kino tree or vijayasar
Family: Leguminosae.

14. Chemical constituents:
• Genus Pterocarpus contains rich sources of polyphenolic compounds.
• The plant contains pterostilbene 45%, alkaloids 0.4%, tannins 5%, protein.
• Non-glucosidal tannins: Kinotannic acid, Kinonin (C28H24O12), Kinored
(C28H22O11), Pyrocatechin, Pyrocatechin acid & small quantities of resin,
pectin and gallic acid.
• flavonol glycoside: 6 hydroxy3,5,7,4tetramethoxyflavone, 6-O
rhamnopyranoside, 8-hydroxy 4’-methoxy isoflavone 7-Oglucopyranoside.
• Marsupin and Pterostilbene significantly lower the blood glucose levels useful in
NIDDM.
• Root contains benzofuranone, marsupin, dihydro chalcone, pterosupin,
stilbene, pterostilbene, homoisoflavonepteromarsupone, trans-
stilbene,liquiritigenin, isoliquiritigenin.

15. Pterostillbene

16. Mechanism:
• Postprandial hyperglycemia is an earliest metabolic abnormality to occur in type
2 diabetes. This state initiates the development of microvascular and
macrovascular complications. Most of the currently available anti-diabetic
therapies reduce the fasting blood glucose but have a little impact on
postprandial hyperglycemia. In this view, P. marsupium at a dose of 200 mg/kg
could be a better drug in treatment of type 2 diabetes. Reduction in blood
glucose may be mediated through enhanced insulin secretion by regeneration of
β-cells of islets of Langerhans.
• It also reduces the elevated levels of the cytokine TNF-alpha because TNF-α
mediates insulin resistance also through indirect effects including increasing free
fatty acids in circulation, stimulation of insulin counter-regulatory hormones,
impairment of endothelial function, or inhibiting the glucose-stimulated insulin
release by pancreatic β-cells.
• Weight loss in diabetes is also generally due to continuous excretion of glucose
from the body. Long-term presence of TNF-α has an appetite suppressing effect.
Improved body weight occurs after drug treatment due to TNF-α modulation.

17. Other Uses:
• Used in diarrhoea.
• Bleeding and gout problems.
• Skin problems.
• Intestinal parasites.
• Dental problems.
• Anti microbial properties.
• Hyperlipidemia.
• Arthritis
Side Effects:
• For the reason that it has astringent properties, It is used to treat
Diarrhoea. Therefore, It is not suggested during constipation.
• Sufferers of diabetic who are already on diabetic treatment should take
this herb with precaution, Because it lowers blood sugar levels.

18. Swertia chirata
Family: Gentianaceae
Common Names: Indian gentian, Bhunimba

19. Chemical Constituents:
Bioactive compounds belonging to different classes such as
xanthones and their derivatives, lignans, alkaloids, flavonoids,
terpenoids. Chiratin was first isolated xanthone.
The pharmacological efficacy of S. chirayita has been partly attributed
to the biological activity of major phytoconstituents including
amarogentin, swertiamarin, mangiferin, swerchirin, sweroside,
amaroswerin, and gentiopicrin. Amarogentin is reported to be anti-
diabetic.

21. Mechanism:
• Swertia chirata has antidiabetic activity and is probably due to the active
principle mangiferin, present in the stem of the plant.
Mangiferin has several modes of action :
i) Direct stimulation of β cells to release insulin
ii) May be due to reduced intestinal absorption of 32 glucose.
iii) Enhances glycolytic enzymes which stimulates glycogenesis in the liver and
thereby
contributes to 33 reduction of blood glucose.
iv)Inhibiting alpha glucosidase inhibitor and other enzymes such as maltase,
sucrase, isomaltase and also-reductase.
v) Increases peripheral utilisation of glucose.
vi) Increases hepatic and muscle glycogen content. Promotes beta cell repair and
regeneration.
vii) Exerts insulin like action by reducing the glycated haemoglobin levels.
viii) Inhibits dipeptidyl peptidase VI mediates glucagon 1.

22. Other Uses:
Hepatoprotective activity.
Anti ulcer.
CNS depressant activity.
Anti inflammatory.
Anti microbial.
Side Effects:
Fever.
Malaria.
Constipation.
Worm infestations.
Upset stomach.
Loss of appetite.
Skin diseases.
Cancer.