Myrocarpus balsam is one of the obsolete balsams of the older pharmacopoeias. E. Schaer2) is of the opinion that it is identical with the Cabureiba balsam described by the Dutch physician Willem Piso about the middle of the 17th century in his Historia naturalis Brasiliae IV. 5, 57, also with the Baume du Perou en coques of Guibourt's Histoire naturelle des drogues simples.
The Myrocarpus fastigiatus, Allem. and the M. frondosus, Allem., both of which are natives of central Brazil, yield a balsam from natural wounds and from incisions. For its collection, fruits of the size of a walnut, that have been hollowed out and which are obtained either from certain palms or certain Myrtaceae, are used. After having been allowed to dry for several days the fruits are sealed with a plant wax. The balsam itself is reddish-brown and, aside from its tough consistency, greatly resembles Peru and tolu balsams as to appearance, odor and other properties. Schaer found it to contain benzoic acid, free as well as combined with aromatic alcohols. Cinnamic acid and vanillin he could not find.
In the ethereal extract A. Tschirch and J. O. Werdmuller3) found benzoic acid (m. p. 121°) but could not detect any cinnamic acid. In the saponification liquid of the resin, vanillin was found.
The volatile oil which may be supposed to possess properties similar to those of Peru balsam, has not yet been isolated.