4. SOLANINE.
§ 461. Distribution of Solanine.—Solanine is a poisonous nitrogenised glucoside found in all parts of the plants belonging to the nightshade order. The English common plants in which solanine occurs are the edible potato plant (Solanum tuberosum), the nightshade (Solanum nigrum), and the Solanum dulcamara, or bitter-sweet. The berries of the Solanum nigrum and those of S. dulcamara contain about 0·3 per cent. Mature healthy potatoes appear to contain no solanine, but from 150 grms. of diseased potatoes G. Kassner[515] separated 30 to 50 mgrms.
[515] Arch. Pharm. (3), xxv. 402, 403.
R. Firbas,[516] in a research on the active substances or young shoots of the S. tuberosum found two products—one crystalline, Solanine; the other amorphous, Solaneine. He gives the following formula to solanine—C52H93NO1841⁄2H2O; when dried at 100° it becomes anhydrous. From a solution in 85 per cent. alcohol it crystallises in colourless needles, m.p. 244°; these are almost insoluble in ether and alcohol, but are readily dissolved in dilute hydrochloric acid. On hydrolysis solanine breaks up into solanidine and a sugar, according to the equation—
C52H93NO18 = C40H61NO2 + 2C6H12O6 + 4H2O.
[516] Monatsh., x. 541-560; Journ. Chem. Soc. (Abst.), Jan. 1890.