Page 313 - Pharmacognosy 2 PG303

Pharmacognosy-2 (PG303) Level 2 Clinical Pharmacy-Pharm D

of chondrin is indicated also by the solubility of gelatin in acetic acid and by its
failure to produce a precipitate with alum T.S., solution of lead acetate, ferric
chloride T.S., copper acetate T.S., or mercuric chloride T.S. Gelatin should be
also free from albumin where no black precipitate is formed with lead acetate
solution.
2- Millon’s reagent test: To an aqueous solution of Gelatine, add Millon’s reagent;
a white precipitate is formed, becoming brick-red on warming.
3- Soda lime test: Heat Gelatine with soda lime; ammonia gas is evolved.

Constituents
Gelatine consists chiefly of the protein glutin. It responds to the usual tests
for proteins.

Uses
Apart from its various technical uses, gelatine has been employed as a nutrient
and as a styptic, but its value for these purposes has been over-rated. It is also used
as a basis for glycerine suppositories, for the preparation of pastilles and for the
preparation of nutrient media for the growth of bacteria, some of which cause
liquefaction of the medium.

Gambir

Syn.: Pale Catechu; Catechu; Gambier; Terra Japonica; Gambir-Katechu.

Gambir is the dried aqueous extract prepared from the leaves and twigs of
Uncaria Gambier (Hunter) Roxb. (Fam. Rubiaceae).

The plant is a climbing shrub indigenous to the Malay Archi-pelago and
largely cultivated on the small islands between Singapore and Sumatra, and on other
islands of the Archipelago.

Preparation
When the plants are about 8 years old, the shoots are cut down and the young
leafy plants are thrown into a specially constructed container, three-quarters full of
boiling water. The contents are boiled for about 3 hrs; being stirred and bruised with
a four-pronged wooden fork. The marc is finally removed by wooden forks having
three large flat prongs and is thrown on to a sloping trough about 6 metres long and
projecting over the edge of the container so that the liquor may drain back into it,
the marc is washed with a little water and is pressed in the trough. The decoction is
evaporated for about 1.5 hrs till it turns yellowish-green, thick, and pasty. It is then

255