Oleum Pimentae. U. S. Oil of Pimenta.
Ol. Piment. [Oil of Allspice, Pimento Oil]
Related entry: Pimenta
"A volatile oil distilled from the fruit of Pimenta officinalis Lindley (Fam. Myrtaceae), yielding not less than 65 per cent., by volume, of eugenol [C10H12O2 = 164.10]. Preserve it in well-stoppered, amber-colored bottles, in a cool place, protected from light." U. S.
Oleum Amomi; Oil of Pimento; Huile volatile (Essence) de Piment de la Jamaique, Fr.; Nelkenpfefferöl, Pimentöl, G.
Oil of pimenta was deleted from the British Pharmacopoeia 1914.
The berries yield from 1 to more than 4 per cent. of the volatile oil, which as found in commerce is brownish-red, and has the odor and taste of pimenta, though warmer and more pungent. It has a slightly acid reaction.
"Oil of Pimenta is a colorless, yellow or reddish liquid, becoming darker with age and having the characteristic odor and taste of allspice. It is soluble in an equal volume of 90 per cent. alcohol; also soluble in 2 volumes of 70 per cent. alcohol. Specific gravity: 1.018 to 1.048 at 25° C. (77° F.). The optical rotation varies from 0° to -4° in a 100 mm. tube at 25° C. (77° F.).
It consists, like oil of clove, of two distinct portions, one a sesquiterpene, C15H24, and the other a phenol, eugenol, capable of extraction by shaking out with alkaline hydroxide solution. They may be separated by distilling the oil from potassium hydroxide solution. After the hydrocarbon is distilled off the phenol may be obtained by liberation from its combination with sulphuric acid and distilling. It is readily recognized as eugenol, so that oil of pimenta is analogous in its constitution to oil of clove (see Oleum Caryophylli). Nothing is known of the constituents which give oil of pimenta its characteristic odor.
Oil of pimenta is given for the same purposes as are the other stimulant aromatic oils.
Dose, from three to six minims (0.2-0.4 mil).
Off. Prep.—Liquor Pepsini Aromaticus, N. F.; Spiritus Myrciae Compositus, N. F.