Page 325 - Pharmacognosy 2 PG303

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

Description
Colophony occurs in large compact, angular, brittle, glassy pale amber to
brownish-yellow masses, frequently covered with a yellow powder; transparent in
thin splinters; fracture, glassy and conchoidal; pulverizable to a pale, almost white
powder; odor, and taste, slightly terbinthinate. Colophony is readily fusible and
burns with a dense yellow smoke.

Solubility
Colophony is insoluble in water, but is soluble in alcohol, in chloroform, in
ether, in benzene, in carbon disulphide, in glacial acetic acid, in fixed and volatile
oils, and in dilute solutions of potassium and sodium hydroxides. It is partially
soluble in petroleum ether.

A, T.S. of the wounded trunk T.S. through the wood of a
of a pine tree. Pinus species showing an
B, T.L.S of the youngest oleo-resin duct, c
wood showing large
anastomosing oleo-resin
ducts.
a, annual rings; c, cambium;
ckr, cork and rhytidome;
m.r., medullary ray; o.r.,
oleo-resin; or.d., oleo-resin
duct; s.ph., secondary
phloem; w, wound; y.w.,
youngest wood ring.

Tests for Identity
1- Test for terpenes: To 10 ml of a 1 % solution of colophony in acetic
anhydride reagent, add 1 drop of sulphuric acid; a bright purplish-
red colour is produced, which rapidly changes to violet.
2- Test for abietic acid: Shak about 0.05 g of freshly powdered
Colophony with 5 ml of petroleum ether for few minutes, and filter.
Shake the filtrate with an equal volume of dilute copper acetate T.S.;
the petroleum ether layer assumes a bright bluish green (emerald,
green) colour.

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