Page 343 - Pharmacognosy 2 PG303

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

1. Effect of water: The solution of Benzoin in alcohol becoming milky on the
addition of water and the mixture is acid to litmus paper.
2. Sublimation: Heat cautiously about 0.5 g of Benzoin in a dry test tube; it melts
and evolves irritating whitish fumes, which condense in the case of Sumatra
Benzoin, on the upper part of the tube to form a whitish crystalline sublimate
consisting of plates and small rod-like crystals of cinnamic and benzoic acids that
strongly pola-rise light while, in the case of Siam Benzoin, the sublimate is
directly above the melted mass and consisting of long rod-shaped crystals of
benzoic acid which do not strongly polarise light.
3. Effect of potassium permanganate: Warm gently about 0.5 g of coarsely
powdered Benzoin with10 ml of potassium permanganate T.S. in a test tube; a
faint odor of benzaldehyde is developed only with Sumatra Benzoin.
4. Effect of sulphuric acid: Digest about 0.2 g of coarsely powdered Benzoin with
5 ml of ether for about 5 mins., decant about 1 ml of the ethereal solution into a
porcelain dish containing 2-3 drops of sulphuric acid and mix carefully; a deep
reddish-brown colour is produced with Sumatra Benzoin, and a deep purplish-
red colour with Siam Benzoin.

Constituents
Sumatra Benzoin contains about 75 % of a resinous substance known as
benzoresin which consists of 92 % of an ester of cinnamic acid and resinotannol, and
an ester of cinnamic acid and benzoresinol. On saponification, benzoresin yields 30
% of cinnamic acid, 64 % of resinotannol and 5 % of benzoresinol. Sumatra Benzoin
also contains 17 % of cinnamic acid and 9 % of benzoic acid (free and in combin-
ation), traces of benzaldehyde, vanillin and cinnnamic cinnamate.

Siam Benzoin contains about 90 % of a resinous substance known as
siabenzoresin which consists of 90 % of an ester of benzoic acid and siaresinotannol
and an ester of benzoic acid and benzoresinol. On saponification siabenzoresin
yields 38 % of benzoic acid, 56 % of siaresinotannol and 5 % of benzoresinol. Siam
Benzoin also contains 12 % of free benzoic acid, very little or no cinnamic acid and
traces of vanillin.

Uses
Benzoin possesses antiseptic and stimulant properties when applied
externally, and having carminative, expectorant and diuretic properties when taken
internally.

Balsam of Peru

Syn.: Peruvian Balsam; Peru Balsam; Balsamum Peruvianum

285