Benzoe

BENZOE, Benzoe sive Asa dulcis, rosin incense, resin obtained from incisions in the tree Styrax benzoides, or Styrax benzoin Dryander (Benzoin officinale Hayne) of the Styraceae family. Styrax benzoin grows in Indochina, Siam, Sumatra, and the Moluccas. In commerce, two best grades of rosin incense are distinguished: Siamese and Sumatran. They have great similarity in appearance but differ in composition. Siamese B. contains benzoic acid, Sumatran B. contains also cinnamic acid. For examination, rosin incense is boiled with water, the solution is concentrated and potassium permanganate is added during boiling; the smell of bitter almonds (benzaldehyde) will indicate the presence of cinnamic acid. B. is little soluble in chloroform, almost insoluble in water, best in hot alcohol. An alcoholic solution of B. when diluted with water gives a milk-like liquid. With concentrated H₂SO₄, Siamese B. gives a carmine-red coloration. In medicine, B. is used as an antiseptic and expectorant. Preparations: Resina Benzoe, dose 0.03-0.3; Tinctura Benzoes simplex et composita - 5-20 drops per dose; Adeps suillus benzoatus (Ph. VII).