Page 361 - Pharmacognosy 2 PG303

Constituents Pharmacognosy-2 (PG303)

yellow crystalline anthraquinone glyco
barbaloin, resin, aloe-emodin (hydroly
decomposition product of barbaloin).

Uses • Purgative (used in constipation as
Tests for Identity digestion and does not lose its act
repetition).

• treatment of burns, skin irritations
effects

0.5 g powder + 50 ml water → boil for 2-3 mi
kieselguhr → shake and filter
→ clear filtrate, the clear filtrate responds to
identification:

1-Borax test for anthranols:

0.2 g borax + 5 mL filtrate → Dissolve by hea
drops of this solution to a test tube nearly fille

green fluorescence Is produced due to
aloe-emodin anthranol liberated from

hydrolysis with borax

2- Test for free anthraquinones:

10 mL filtrate + 20 mL ether → shake 10 mL
mL of diluted Soln
of NH4OH

A rose red color is produced in ammo
3- Test for barbaloin (Bromine wate

1 mL filtrate + 1 mL bromine T.S

pale yellow ppt. is formed