Page 19 - Phytochemistry -1 (PG404) / Clinical Pharmacy 2nd level students ( 2019 )

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

Determination of adulteration:

1- Quantitative determination of reducing sugars in the sample before

and after hydrolysis (% of reducing Sugar increases with sucrose
adulteration).

2-Test for Commercial and liquid glucose: It contains dextrin which
reacts with I₂, to develop a reddish-brown color.

3-Test for invert sugar or artificial honey.

Invert sugar: it is obtained from sucrose by acid hydrolysis with citric or
tartaric acid heating to ~115°C. This hydrolysis results in the production of
furfural derivatives (oxymethyl furfural) which is a decomposition product
of fructose and can be tested as follows:

Detection of invert sugar or artificial honey (Reactions of oxymethyl
furfural)

1. Aniline acetate paper gives bright red color.

2. Resorcinol test gives pink color, after 20 min. cherry red.

Polysaccharides

I. Homo - polysaccharides ( Starch and Dextrin ).

A. Starch = Amylum in E.P.

Starch is used for energy storage in plants. It is found in all plant seeds and
tubers and is the form in which glucose is stored for later use. Starch can

be separated into two principal polysaccharides: amylose and amylopectin.
Complete hydrolysis of both amylose and amylopectin yields only D-
glucose.

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