Page 24 - phytochemistry I - PharmD Clinical

 They are translucent, amorphous substances that are frequently
produced in higher plants as a protective after Injury.

 Gums are typically heterogenous in composition, Upon
hydrolysis, arabinose, galactose, mannose, xylose and various
uronic acids are the most frequently observed components.

 The uronic acids may form salts with calcium, magnesium and
other cations.

 Generally speaking, gums are pathogenic products.

Gum Acacia

Occurrence:
 Acacia (Gum Arabic) is the dried gum obtained from the stems and branches of

Acacia senegal and some other species of Acacia (Leguminosae).

Chemical composition:
 It consists mainly of arabin which is a mixture of the calcium, magnesium

and potassium salts of Arabic acid.
 Acacia also contains an oxidase enzyme, about 14% water and small

amounts of protein including arabinogalactan-protein.
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:

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