Chemical examination of Micromeria chamissonis (Yerba buena) / by Frederick B. Power and Arthur H. Salway.

  • Power, Frederick B. (Frederick Belding), 1853-1927
Date:
[1908?]
Catalogue details

Licence: In copyright

Credit: Chemical examination of Micromeria chamissonis (Yerba buena) / by Frederick B. Power and Arthur H. Salway. Source: Wellcome Collection.

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    solid remained. This was crystallized from acetic acid, from which it separated in pearly leaflets, melting at 61.5°. It was analyzed with the following result: 0.0914 gave 0.2506 C02 and 0.1073 H20. C = 74.8; H = 13.0. Clt5H3202 requires 0 = 75.0; H = i2.5 per cent. - This solid substance was thus identified as palmitic acid. Examination of the Alcoholic Extract of the Plant. For the purpose of a complete examination of the constituents of the plant, 36 pounds (i61/s kg.) of air-dried material were extracted by con¬ tinuous percolation with hot alcohol. After the removal of the greater portion of the alcohol, a dark green, thick extract was obtained, which weighed 4170 grams. Of this extract, 3.5 kg. were mixed with water, and the mixture distilled with steam until all the volatile substances present had been removed. Volatile Constituents of the Alcoholic Extract. The distillate obtained, as above described, had a distinctly acid re¬ action and contained a quantity of essential oil floating on the surface. It was extracted twice with ether, after which the ethereal liquid was washed with a little water, dried with anhydrous sodium sulphate, and the ether removed. About 20 grams of a pale yellowish brown essential oil, possessing an aromatic, mint-like odor, were thus obtained. When distilled under a pressure V>f 25 mm. it passed over between 8o° and 160°, but the greater portion boiled between 120° and 140°. The oil had a density of 0.9450 at 20°, and an optical rotation of —26° 44' in a 1 dcm. tube. It was readily soluble in 70 per cent, alcohol, thus differing from the essential oil distilled directly from the dried plant. The acids contained in the aqueous distillate from which the essential oil had been removed were neutralized with baryta, and the liquid con¬ centrated. About 3 grams of a barium salt were thus obtained in the form of a thick syrup, which afforded reactions indicating the presence in the distillate of formic, acetic, and butyric acids, the latter being relatively small in amount. Non-volatile Constituents of the Alcoholic Extract. After the removal of the essential oil and volatile acids by distillation with steam, as above described, there remained in the distilling vessel a reddish-brown, aqueous liquid (A) together with a large quantity of a dark green, soft resin (B). The resin was separated by filtration from the liquid, while still hot, and washed well with hot water, the washings being added to the filtrate. Examination of the Aqueous Liquid (A). The aqueous liquid, which was of a reddish brown color, and pos-