. Cellular toxins; or, The chemical factors in the causation of disease. Poisons; Pathology; Bacteria. 232 METHODS OF EXTRACTING PTOMAINS. Chloroform, amylic alcohol, and benzene are used as solvents after extraction with ether. Dragendorffs Method.—The finely divided substance is digested for some hours with water acidulated with sulphuric acid, at from 40° to 50°. This is repeated two or three times, and the united filtered extracts are evaporated to a syrup, which is treated with four volumes of alcohol and digested for twenty-four hours at 30°. After cooling, the alcoholic extract is filte
. Cellular toxins; or, The chemical factors in the causation of disease. Poisons; Pathology; Bacteria. 232 METHODS OF EXTRACTING PTOMAINS. Chloroform, amylic alcohol, and benzene are used as solvents after extraction with ether. Dragendorffs Method.—The finely divided substance is digested for some hours with water acidulated with sulphuric acid, at from 40° to 50°. This is repeated two or three times, and the united filtered extracts are evaporated to a syrup, which is treated with four volumes of alcohol and digested for twenty-four hours at 30°. After cooling, the alcoholic extract is filtered, the residue washed with 70 per cent, alcohol, and the united filtrates freed from alcohol by distillation. The aqueous residue, diluted if desirable, is filtered and submitted to the following extractions : 1. The acid liquid is shaken with freshly rectified petroleum ether, as long as this reagent leaves a residue on evaporation. 2. The acid fluid is now extracted with benzene. 3. The next solvent used is chloroform. 4. The liquid is now again extracted with petroleum ether in order to remove traces of benzene and chloroform. 5. The liquid is next made alkaline with ammonia and succes- sively extracted with petroleum ether, benzene, chloroform, and amy- lic alcohol. 6. The remainder of the ammoniacal liquid is mixed with pow- dered glass, evaporated to dryness, the residue pulverized, and ex- tracted with chloroform. The residue obtained with each of the above solvents should be examined for ptomains. Brieger's Method.—The substance under examination is divided as finely as possible, and then heated with water slightly acidified with hydrochloric acid. During the heating care must be taken that the feebly acid reaction is maintained, and the heat should continue for only a few minutes. The liquid is then filtered and concentrated, at first on a plate and then on the water-bath, to a syrup. If one has highly odorous material, a piece of apparatus devised by Bocklisc
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectpoisons, bookyear1902
