This section is from the book "A Text Book Of Materia Medica, Being An Account Of The More Important Crude Drugs Of Vegetable And Animal Origin", by Henry G. Greenish. Also available from Amazon: A Text Book of Materia Medica : Being an Account of the More Important Crude Drugs of Vegetable and Animal Origin.
The laurel produces one-celled, one-seeded, drupaceous fruits, which are collected when ripe, and dried. They are then nearly black in colour and ovoid in shape, about 15 mm. long, and slightly pointed at the apex. The surface is glabrous, shining, and coarsely wrinkled. The pericarp is thin and brittle, and encloses a single seed, the kernel of which lies loose in the cavity, the seed coats remaining closely adherent to the inner surface of the pericarp. The kernel is usually brownish yellow in colour, and easily separable into two large firm cotyledons; it has an aromatic odour and aromatic bitter taste, the pericarp being less aromatic but much more bitter.
The student should observe
(a) The ovoid shape,
(b) The loose kernel of the seed,
(c) The aromatic odour and taste; and should compare these fruits with Cocculus indicus, which are reniform in shape and destitute of aroma.
Laurel berries contain about 1 per cent, of an aromatic volatile oil and upwards of one-fourth of their weight of solid fat. The latter, separated by hot pressure, is the Oleum Lauri Expressum of commerce; when pure it has a dull green colour, granular consistence, and aromatic odour. The principal constituent is laurostearin (glyceryl laurate), the odour being due to the volatile oil, and the green colour to chlorophyll, both of which are simultaneously extracted.
The volatile oil consists of cineol (eucalyptol, 50 per cent.), accompanied by eugenol, pinene, geraniol, etc.
The nature of the bitter principle contained in the pericarp of the fruit is unknown.
The expressed oil is sometimes used as a stimulant in veterinary practice.
Fig. 71. - 1 and 2, Laurel berries, whole and cut vertically. 3 and 4, Cocculus indicus, whole and cut transversely. Slightly magnified. (Vogl).