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.
In the axils of certain of the upper leaves small rudimentary branches are produced, each of which bears a number of minute bracts; in the axils of the uppermost whorl of three such bracts three ovules are produced, which, as in all gymnosperms, are not enclosed in an ovary. After fertilisation the three supporting bracts increase in size, become fleshy, grow round, and finally, with the exception of a minute canal at the apex, completely enclose the three ovules. At the same time the ovules develop to seeds and become surrounded with hard coats developed partly from the integuments, partly from the tissue of the enclosing bracts. The fruit ripens in the second year, and forms then a purple, berry-like fruit which is termed a ' galbulus.'
Fig. 77. - Juniper berry. A, entire fruit, magnified 3 diam. B, transverse section of the same; k, seed. D, Seed, magnified 3 diam.; I, oil-gland. (Berg).
Juniper berries are collected in various parts of Europe, but especially in Italy and in Hungary.
Ripe juniper berries are of a dark purplish colour and nearly globular shape, measuring about 8 mm. in diameter. The apex bears a very distinct tri-radiate scar indicating the sutures of the three bracts by which the seeds are enclosed; at the base are (usually) six minute pointed bracts arranged in two whorls. The outer skin (corresponding to the epicarp) is thin and often covered with a bluish ' bloom '; the tissue corresponding to the mesocarp is loose and soft, of a yellowish brown colour, and contains embedded in it three hard' triangular seeds. These usually bear, partly sunk in the hard tissue, large oil-glands filled with volatile oil, or, in old fruits, with yellowish transparent resin; they are often concealed by the soft surrounding tissue which adheres to the resinous secretion. Smaller oil-glands are present in the pulp of the fruit, but they are less conspicuous.
Juniper berries have an agreeable aromatic odour resembling turpentine, and a sweetish taste.
The student should observe
(a) The scar at the apex,
(b) The minute bracts at the base,
(c) The three hard seeds with oil-glands partly embedded in them.
Ripe Juniper berries yield about 1 per cent, of volatile oil (sp. gr. 0.862 to 0.890; O.R. - 3° to - 15°), consisting of pinene, cadinene, and juniper camphor, and contain about 33 per cent, of invert sugar.
The residue left after the distillation of the volatile oil is exhausted with water and the decoction evaporated to a soft sweetish extract much used in Germany (Succus or Roob Juniperi).
The volatile oil is diuretic as well as being stomachic and stimulant. It is employed chiefly as a diuretic in certain forms of dropsy.