Remarks on Ricinin.
By RICHARD V. TUSON, F.C.S.,
Professor of Chemistry in the Royal Veterinary College.
Among the "Chemical Notices from Foreign Sources" which appeared in the Chemical News of the 21st of October last, will be found an extract from an article entitled "On Ricinine and the Active Principles of Ricinus Seeds," published in the Pharmaceutische Zeitschrift für Russland, No. 1, 1870. This extract contained the following statement:—"As regards the ricinine of Dr. Tuson, prepared by the author (Dr. E. Werner) in large quantity, and according to Dr. Tuson's directions, it is stated that ricinine is not an alkaloid, and, moreover, a substance which contains a considerable quantity of ash; and the author, after carefully made analyses, comes to the conclusion that Dr. Tuson's ricinine is a compound of magnesia and of an organic acid, the formula of this body being C11H20O10Mg2+6H2O."
That the bodies obtained by Dr. Werner and myself from castor seeds are totally different, I hope to render evident in the present communication.
I have in my possession two small specimens of ricinine; one was prepared from the so-called castor-cake obtained from India, the other from castor-cake obtained from Italy. These specimens possess the undermentioned properties:—
- Cautiously heated on a glass plate they melt and form a colorless mobile liquid, which, on cooling, solidifies into a whorl of acicular crystals.
- Heated between two watch-glasses they sublime, apparently without decomposition.
- Strongly heated on platinum foil, they first melt, then burn with a highly luminous flame, and leave no ash.
- Heated with solid potassium hydrate, they evolve ammonia, proving that they contain nitrogen.
- On estimating the amount of nitrogen by Péligot's method, the specimen of ricinine procured from Indian castor-cake contained 20.79 per cent., while that from Italian cake contained 20.39 per cent.
- A solution of ricinine in hydrocholoric acid mixed with one of platinic chloride yields, on evaporation, well defined orange octahedra.
- Cold saturated aqueous solutions of ricinine and mercuric chloride, if mixed together and allowed to stand, deposit fasciculi of acicular crystals.
A comparison of the foregoing epitomised account of ricinine with the description of the magnesium compound obtained by Dr. Werner from ricinus seeds, therefore clearly indicates that the two bodies are entirely different.
That ricinine is entitled to the appellation of alkaloid I hope yet to demonstrate by its complete investigation so soon as I shall become possessed of a large supply of castor-cake, now, I believe, on its way from Calcutta.—Chem. News, London,Nov. 11, 1870.