The organic constituents of plants and vegetable substances and their chemical analysis / by G.C. Wittstein ; authorised translation from the German original, enlarged with numerous additions, by Baron Ferd. von Mueller.

Georg Christian Wittstein

Date:: 1878

Credit: The organic constituents of plants and vegetable substances and their chemical analysis / by G.C. Wittstein ; authorised translation from the German original, enlarged with numerous additions, by Baron Ferd. von Mueller. Source: Wellcome Collection.

210/358 (page 188)

$diluted acids into a brown-red, hard i-e.sin (ratanhia-red = Ci2 He O3, also existing i-eady formed in the i-oot), and into a sweet body which reduces the solution of copper. [Ratailllin=C2o Hi3 NOe (Peckolt's Angelin). Contained in the American Ratanhia extract (according to E.uge), and in the resin of Hillia spectabilis. In order to prepare it from the last- named substance, the pulverised resin is repeatedly digested with water, the residue dissolved in water and hydrochloiic acid and evaporated Avith a gentle heat to form crystals. The crystals are freed from the mothex'-ley by pressing, again dissolved in acid water and recrystallised. After repeating this process six or seven times, a white crystalline mass is obtained, which is dissolved in boiling distilled water and set aside to ciystallise.—The Katanliin, purified in this way, j^i'esents delicate, flexible needles, of a pure white colour and a vivid satin lustre. It is neai'ly insoluble in cold, and only sparingly soluble in boiling water; it is still less soluble in alcohol, both cold and boiling, and almost insoluble in ether. It is tasteless, without odour, and of neutral reaction. R. dissolves in acid and in alkaline liquids, but is thrown dowai again on neutralising the solution. It is likewise precipitated by alcohol, alcohol-ether, and in acid solutions by phosi^homolybdic acid and by Nessler's reagent, not by chloride of platinum. Heated above 150° it melts and volatilises in a higher temperature, while emitting a not unpleasant aromatic odour. Quickly heated, it becomes carbonised with a horny odour and under formation of inflammable gases. Ratanliin, when formed into a thin pulp with water and an adequate quantity of dilute nitric acid, and boiled for some time, becomes fii'st of a rose coloixr, and then changes from blood-red to violet and blue, while exhibiting a splendid red fluorescence,] Red Pio'Ilient of Berries is mostly anthocyan, reddened by acids; yet there are some exceptions. For instance, the red of strawberries behaves like cissotamiic acid, likewise, the red pig- ment of the berries of Ligustrum vulgare behaves diflferently and is named ligulin. Red Pig-Ilieilt of FlOAVers is mostly anthocyan, reddened by acids. [Regiaiiill, found by T. L. Phipson in the gi-een pericarp of the walnut {Juglans regia). Crystallises in yellow, protracted octahedra or needles, little soluble in water, better in alcohol and benzol; becomes after a few hours transformed into black, amor- phous Eegianic acid; forms with alkalies sohible salts of a splendid purple colour, with oxyd of lead an insoluble, brown-violet salt. On boiling the aqueous or alcoholic solutions of E. with hydro- •chloric acid, Eegianic acid separates as a dense, black precipitate.]$