Page 314 - Pharmacognosy 2 PG303

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

transferred to wooden tubes holding 4-5 gallons each. The tubes are cooled, and the
contents are stirred with a pole about 30 cm long and 4 cm thick to induce
crystallisation. After about 10 min the semi-crystallised magma is poured into
shallow wooden trays to a depth of 2-3 cm and is allowed to set. While still moist it
is cut with a wooden knife into cubes, which are spread on rattan trays to dry in the
sun. Much gambir is poured into kerosene tins to solidify and is imported in large
blocks. Cube gambir is preferred for pharmaceutical use.

Description
Gambir occurs in approximately cubical or rectangular masses; externally,

dull pale greyish brown to dark reddish-brown; internally, light brown and porous;
friable; odourless; taste, at first bitter and astringent, but sweetish afterwards.

Tests for Identity
1- Microscopical examination: Gambir shows numerous minute acicular crystals

of catechin.
2- Test for catechutannic acid: Macerate about 1 g of powdered Gambir with 50

ml of water for 1 h, and filter. To the filtrate add FeCl3 T.S.; an intense green
colour is produced.
3- Test for gambir-fluorescin: Warn 0.5 g of powdered Gambir with 5 ml of
alcohol 90 %, cool, and filter. To the filtrate, add 5 ml of NaOH T.S., then shake
the mixture with 5 ml of petroleum ether; the petroleum ether layer, on
separation, exhibits a brilliant green fluorescence (c.f. Black Catechu).
4- Warm 1 g of Gambir with 5 ml of chloroform, shake, and filter; the filtrate is
yellowish green.

Constituents
Gambir contains about 7-33 % of catechin and 22-50 % of catechutannic

acid. Other constituents of Gambir are catechu-red, quercetin, and the fluorescent
substance Gambir-fluorescin.

Uses
Gambir is employed medicinally as an astringent in diarrhea. In industry it is

used in tanning, in dyeing and in other technical purposes.

DRIED LATEX

Latex is an emulsion or suspension, the continuous phase of which is an
aqueous solution of mineral salts, proteins, sugars, tannins, alkaloids, etc., and the
suspended particles are oil droplets, resin, gum, proteins, starch, caout chouke, etc.
This turbid fluid is often white in color as in the opium poppy, Papaver somniferum,
but may be yellow or sometimes red. Latex occurs in plants in special structures,

256