Page 21 - Phytochemistry -1 (PG404) / Clinical Pharmacy 2nd level students ( 2019 )

Clinical pharmacy PharmD program Third level Phytochemistry-1 (PG-504)

III. Test

B. Dextrin

It results from incomplete hydrolysis of starch by enzymes (partial
hydrolysis of starch).

I. Classes

Amylodextrin +++ very high molecular + Blue
weight I₂

Erythrodextrin ++ high molecular weight + Red
I₂
Achrodextrin + low molecular. weight + Colorless
I₂

II. Reactions

0.5 gm dextrin + water, boil, cool, a gel is formed, dilute with water then
apply the reactions: I 2, Ethanol, Fehling, lead acetate tests as before with

starch.

II. Hetero - polysaccharides

They can be divided into two distinct groups:

(1) Heteropolysaccharides without acid group, e.g.Neutral hemicellulose.

(2) Heteropolysaccharides contain acid group, e.g. Gums, Mucilages,
Pectins, Acidic hemicellulose. The acidic heteropolysaccharides contain

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