Page 121 - Pharmd general phytochemistry I-Final2024_LEUCTERS

Chemical Tests:
1- It gives no colour with iodine (absence of starch & dextrin) and if of
pharmacopoeial quality, gives no reaction for tannin with ferric chloride.
2- Test for oxidase enzyme by benzidine solution and hydrogen peroxide where it
gives a blue colour (distinction from gum tragacanth).
Uses:
1- As a stabilizer in emulsions and as pharmaceutical necessity in lozenges.
2- Its demulcent properties are employed in various cough, diarrhea and throat
preparations. It is incompatible with readily oxidized materials such as phenols
and the vitamin A of cod-liver oil.
3- As an adhesive and binder in tablet granulation.

Gum Tragacanth

Occurrence:
 Gum Tragacanth is the air-dried gummy exudates obtained by incision from the

trunk and branches of Astragalus gummifer and certain other species of Astragalus
grown In Western Asia (Leguminosae).
Chemical composition:
 Tragacanth consists of a water-soluble fraction known as tragacanthin and a water-
insoluble fraction known as bassorin.
 Tragacanthin contain no methoxyl groups but bassorin contained about 5.38%
methoxyl groups.
Uses:
1- Suspending agent for insoluble powders.
2- As a binding agent in pills and tablets.
3- Emulsifying agent for oils and resins. Tragacanth is the most resistant of the
hydrocolloids to acid hydrolysis and is preferred for use in highly acidic conditions.
In cosmetics as an emollient and demulcent.

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