The leaves of Coriaria myrtifolia, Linné (Rhus Coriaria, Linné). (Rhus coriaria L. is not the same as Coriaria myrtifolia L. -Henriette)
COMMON NAMES:Myrtle-leaved coriaria, Currier's sumach.
Botanical Source.—This is a low, unarmed shrub of the Mediterranean regions. The leaves are opposite, entire, lanceolate, acute, short petiolate, and prominently 3-veined. The flowers are small, inconspicuous, in erect, terminal racemes. The sepals are 5, and imbricated in the bud. Petals 5, fleshy, gland-like and shorter than the calyx. The carpels are 5, distinct, and each is furnished with a long, thick, exserted stigma, which protrudes from the bud, and forms the most conspicuous part of the flower. The fruit is a small, black berry, not larger than a common pea.
History.—This shrub grows in Mediterranean Europe and Asia, and has been cultivated in gardens for ornamentation and for the leaves, which yield a black dye. The leaves have likewise been employed to adulterate senna—a dangerous fraud, as, according to Dr. Masters, they have caused convulsions and subsequent coma. The most distinctive characteristic is to be found in the three prominent veins of the leaves, whereas senna leaves have but one. The fruit of this shrub is poisonous, having proved fatal to French soldiers at Catalonia, who ate of it.
Description.—Coriaria leaves are from 1 to 1 ½ inches in length, smooth, entire, ovate-lanceolate, of a shiny bluish-green above, paler beneath, marked by a prominent mid-rib and two lateral nerves running near the border of the leaf nearly to the apex. They have an acrid, bitter, and very astringent taste.
Chemical Composition.—The leaves contain a poisonous bitter principle, investigated by Riban (1865), and named coriamyrtin (C30H36O10). It is obtained by precipitating the aqueous extract of the leaves with subacetate of lead; filtering, treating the filtrate with sulphide of hydrogen; filtering again, and evaporating the filtrate to a syrupy consistence, from which substance ether dissolves the coriamyrtin; it may subsequently be purified by recrystallization from alcohol. It is a neutral, white body, very bitter, forming in from 4 to 6-sided prisms, which are soluble in 70 parts of cold and slightly more soluble in boiling water; are very soluble in boiling and in 60 parts of cold alcohol, also soluble in ether, chloroform, and benzol, but only slightly so in carbon disulphide. Dilute acids split it into a substance resembling sugar, and a resin (Husemann and Hilger, Pflanzenstoffe, 1884). In addition to this principle, the leaves contain tannin and are used for tanning leather and dyeing black. For microscopical tests for coriamyrtin, see T. F. Hanausek, Amer. Jour. Pharm., 1893, p. 135.
Action, Medical Uses, and Dosage.—Both the leaves and berries are poisonous. M. Riban gave about 3 grains of the bitter principle to a large dog, and, although it was immediately ejected, horrible convulsions occurred in about 20 minutes, followed by death in 75 minutes; 1 grain of coriamyrtin killed rabbits, and the subcutaneous injection of 3/10 of a grain killed a rabbit in 25 minutes. The symptoms following its administration to these animals were rapid succussions of the head extending to all the limbs, clonic and tetanic convulsions coming on in paroxysms; contractions of the pupils, trismus, and foaming at the mouth; the animals died from asphyxia and nervous exhaustion. Autopsy revealed vessels gorged with brown blood, coagulated in the cardiac cavities, the pulmonary artery, and the inferior vena cava; brown patches on the lungs; injection of the meninges; rapid cadaveric rigidity. No irritating action appeared upon the digestive tube. In cases where children have accidentally eaten the fruit, the symptoms have been a condition like that occasioned by alcohol (drunkenness), aphasia, frothing, purplish countenance, nausea, vomiting, convulsions, and death in from 15 to 20 hours. The plant has not yet been employed in medicine. The New Zealanders have a toot-poison, which is very destructive to human and animal life, and which, it is stated, is procured from Coriaria sarmentosa, Forster. Coriaria ruscifolia is also reputed poisonous.