Gleanings from the German Journals.
By J. M. MAISCH.
Curcumin has been obtained by F. W. Daube in deep yellow crystals, of a pearly to diamond-like lustre. Turmeric is completely exhausted with hot water and, after drying, treated with boiling benzole, which, on cooling, separates crude curcumin. This is dissolved in cold alcohol, the filtrate precipitated by acetate of lead, and the liberated acetic acid almost neutralized by subacetate of lead; the precipitate is decomposed under water by a current of sulphuretted hydrogen, the sulphide of lead exhausted with boiling alcohol, and the alcoholic solution slowly evaporated. Curcumin is readily soluble in alcohol and ether, but requires 2600 parts of benzole for solution, which menstruum does not dissolve the resins, from which curcumin is otherwise difficult to liberate.—Zeitschr. f. Chem. Jan. 21, 1871, from Ber. d. d. Chem. Gesellsch. Berlin, 1870, 609.
Opium Wax.—The glaucous coating of the ripening poppy capsule is wax, which, being scraped off with the hardening milk juice, is likewise a constituent of opium. O. Hesse has prepared it from the residue left on exhausting opium with water. The mass was first treated with some hydrate of lime, and then exhausted with boiling alcohol. The white crystals, after having been recrystallized, are treated with boiling chloroform, which leaves colorless crystals probably related to lactucerin and hyoscerin. From the chloroform solution the pure wax is obtained as cerotate and palmitate of ceryl, by fractional crystallization.—Ibid., from Ibid. p. 637.
To Prevent Mucilage from Mouldiness.—Instead of carbolic acid, corrosive sublimate, &c., the Polyt. Notizbl. recommends to add a minute quantity of sulphate of quinia, and suggests that it might also be useful for ink.—Ph. Cent. Halle, 1871, 182.
Inuloid is, according to O. Popp, contained in the tubers of dahlia and helianthus at a time when the deposition of inulin in the cells has but just commenced. It is obtained from the juice by precipitating gum, coloring matter, &c., by subacetate of lead. The filtrate, after standing for several hours, again produces a precipitate, more of which may be obtained on concentrating the liquid. The white amorphous substance shows nearly the same physical and chemical behavior as inulin, but differs in being lighter and more soluble in water. Its ultimate composition being that of inulin, the author regards it as a soluble modification of this principle.—Archiv d. Ph. 1871, April, 40-46.
Preservation of Ergot.—A. Hirschberg recommends to select unbroken grains only, and, after drying them carefully at a moderate heat, to preserve them in small well-sealed vessels, previously dried. When desirable to keep on hand some bruised and powdered ergot, the same precautions are recommended. The absorption of moisture and contact with the air induce changes, and the slightest odor of propylamin is a sure sign that decomposition has commenced.—Ibid., 88, 89.