Page 77 - Phytochemistry -1 (PG404) / Clinical Pharmacy 2nd level students ( 2019 )

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

of 1% sodium nitroprusside solution and 1 ml of 5% alcoholic sodium

hydroxide. The development of a violet color indicates the probable

presence of cardenolides.

4-Test for tannins

Extract about 10 g of the powdered drug with 25 ml of 50% ethyl alcohol

and filter. Test the clear alcoholic filtrate as follows

a- Add ferric chloride T.S, a blue color indicates the presence of

pyrogallol (hydrolyzable) tannins, and a green color indicates the

presence of catechol (condensed or non-hydrolyzable) tannins.

b- Dip a match stick in the alcoholic solution, allow to dry spontaneously,

then dip again in hydrochloric acid, remove and dry near a flame, a

magenta red color indicates the presence of catechins.

c- To 5 ml of the alcoholic extract add 2 ml of vanillin-hydrochloric acid
solution, a rose red color indicates the presence of gallic acid.

d- To 5 ml of the alcoholic extract add 2 ml of freshly prepared bromine
water, the formation of a precipitate indicates the presence of tannins

of non-hydrolysable type.
e- To 5 ml of the alcoholic extract, add 0.5 g of acid sodium phosphate,

warm, cool, and filter. To the filtrate, add sufficient quantity of 2%

solution of phenazone, the formation of a precipitate indicates the

presence of pyrogallol.

5- Test for flavonoids

Macerate about 10 g of powdered drug in 150 ml of I% hydrochloric acid

and filter. Test for flavonoids as follows

a- Render 10 ml of the filtrate alkaline with sodium hydroxide T.S., a

yellow color indicates the probable presence of flavonoids.

b- Shake 4 ml of the filtrate with 5 ml of amyl alcohol, the formation of

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