Page 164 - Pharmacognosy-I (02-06-06-102)

Galls are Pale buff, yellowish or whitish-brown with a small central
cavity, surrounded by a hard layer and generally containing the remains
of the larva or the pupa of the gall wasp.

Constituents :

- Galls contain from 50-70% of the tannin known as gallotannic acid,
about 2-4% gallic acid, also contain ellagic acid, sitosterol, starch,
calcium oxalate.

Test of identity :

- Moisten about 0.1 g of powder gall with alcohol, shake with 10 ml
of water for 5 minutes, filter dilute 10 drops of the filtrate to 10 ml
with water and add a drop of ferric chloride T.S. a distinct blue
colour is produced.

Uses :

Galls are used in treatment of hoemorrhoids. Galls are also used as a
source of tannic acid, for tannining and dyeing, and in the manufacture
of inks. Tannic acid is used as an astringent.

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