Balsam Of Tolu

BALSAM OF TOLU

Synonyms

Tolu Balsam; Thomas balsam; opobalsam; resin tolu; balsam of tolu; balsamum tolutanum.

Biological Source

Tolu Balsam is obtained by incision of stem of Myroxylon balsamum (L.) Harms., belonging to family Papilionaceae.

Geographical Source

The plant grows in Colombia (near lower Magdalena and Canca rivers), West Indies, Cuba, Venezuela, and Peru. The trees are cultivated in the West Indies.

Collection

Tolu Balsam is a pathological resin and is formed in trunk tissues as a result of injuries. It is collected all the year except the period of heavy rains by making V-shaped incisions in the bark and sap wood. Calabash cups are placed to receive the flow of balsam. Many other incisions are made on higher portion on the trees. Collected balsam is transferred into larger tin containers and exported.

Characteristics

Tolu Balsam occurs as soft, yellowish-brown or brown, semisolid, or plastic solid, transparent in thin layers, brittle when old, dried or kept in cold, odour aromatic, and taste is aromatic, vanilla-like, and slightly pungent. It is insoluble in water and petroleum ether; soluble in alcohol, benzene, chloroform, ether, glacial acetic acid, and partially soluble in carbon disulphide and NaOH solution. On keeping it turns to a brown, brittle solid. It softens on warming. Under microscopical examination shows crystals of cinnamic acid, amorphous resin and vegetable debris.

    Myroxylon balsamum (L.) Harms

Chemical Tests

1.     Alcoholic solution of Balsam Tolu (1 g) gives green colour with ferric chloride due to toluresinotannols.

2.     Alcoholic solution of Balsam Tolu is acidic to litmus paper.

3.     To filtered solution of Balsam Tolu (1 g) in water (5 ml) aqueous potassium permanganate solution is added and heated for 5–10 min. Odour of benzaldehyde is produced due to oxidation of cinnamic acid.

Chemical Constituents

Tolu Balsam contains resin (80%) which is a mixture of resin alcohols combined with cinnamic and benzoic acids.

The aromatic acids are also present in free state in proportions 8–15%. The other constituents reported in the drug are benzyl benzoate, benzyl cinnamate, vanillin, styrene, eugenol, ferulic acid, 1,2-diphenylethane (bibenzyl), mono-and sesquiterpene hydrocarbons, alcohols, and triterpenoids. Tolu Balsam contains 35 to 50% of total balsamic acids calculated on the dry alcohol-soluble matter.

Uses

Balsam of Tolu is used as an expectorant, stimulant, and antiseptic. It is an ingredient of cough mixtures and compound benzoin tincture. It is also used as a pleasant flavouring agent in medicinal syrups, confectionery, chewing gums, and perfumery.

Adulteration

Balsam of Tolu is mainly adulterated with colophony and exhausted tolu balsam. In exhausted tolu balsam, the cinnamic acid is removed previously by heating. The adulterant can be identified by heating it with water and observing under microscope; crystals of cinnamic acid are not seen.