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Rh and isolinolenic acids, the lattter preponderating; and (4) oleic acid, in relatively small amount. In addition to the fatty oil, gynocardia seeds contain 5 per cent, of a crystalline glucoside, gynocardia, C12H19O9N, l½H2O, and a hydrolytic enzyme, gynocardase. (Power and Barroncliff, Trans., Ch. S. LXXXVII, p. 896, et seq.) Gynocardin, a new cyanogenetie glucoside. Power and Gornall have (shown Chem. Soc. Proc, 1904) that when the seeds of Gynocardia odorata are crushed and brought into contact with water, hydrogen cyanide is formed, owing to the presence in the seeds of a cyanogenetic glucoside, which was isolated and designated gynocardin. They have determined its constitution. Four Kilos of the powdered gynocardin seeds were first extracted with cold petroleum, for the complete removal of the fatty oil, and then with 25 per cent, alcohol. On expelling the alcohol from the extract, a dark syrupy residue was obtained, which soon formed a paste consisting chiefly of a crystalline substance; this was separated from the mother-liquor, digested for several minutes with warm ethylacetate, and again separated. A further quantity of the crude glucoside was obtained from the syrupy alcoholic mother-liquor, by first mixing it with " prepared saw dust," drying the mass and extracting it with ethylacetate, which slowly removes the glucoside. The crude glucoside was purified by dissolving it in water, treating the solution with animal charcoal, and evaporating under diminished pressure to a syrup, which set to a hard cake of colourless crystals which were dried on porous earthenware. The yield was 200 grams. Gynocardia forms colourless, glistening, prismatic needles of the composition C13H19O9N+1½H2O ; the water is expelled at 115°0. The anhydrous compound melts at 162°-163°C, and has the optical rotation (a) D2l°=+72.5° in aqueous solution. It is readily hydrolysed at the ordinary temperature by gynocardase; an enzyme contained in the seeds, but only with difficulty by boiling with 5 per cent, hydrochloric or sulphuric acid. Dextrose and hydrogen cyanide were isolated from the products of the reaction, but the third substance, C6H8O4, which should be produced, according to the equation:-

C13H19O9N+H2O=C6H12O6+C6H8 O4+HON, is decomposed by secondary reactions. Gynocardin differs from other known cyanogenetic glucosides in its relatively great stability towards acid hydrolysing agents. It is hydrolysed by treatment with barium hydroxide solution, ammonia and the barium salt of gynocardic acid C12H19O9CO2H, being formed, according to the equation: C13H19O9N+2H20=C12H19O9 .Co2H4-HN3. This acid forms dextrose and an acid, C7H10O6, on hydrolysis with acids. The results obtained indicate that gvnocardia is the dextrose either of the cyanohydrin of a trihydroxy— aldehde or ketone, in accordance with one of the following formulae:
 * C5H4(OH3 3 .CH(CN)O.C6H11O5, or
 * C5H5(OH)3 C(CN), O.C6H11O5

The enzyme gynocardase was isolated by treating the finely-ground seeds with light petroleum to remove the fatty oil, and then digesting them with water, at the ordinary temperature, for 24 hours. The filtered liquid was treated with twice its volume of alcohol, and after standing for some hours,