The chemical investigation of some poisonous plants in the n.o. solanaceæ / by James M. Petrie.

  • Petrie, James M.
Date:
1917
Catalogue details

Licence: Public Domain Mark

Credit: The chemical investigation of some poisonous plants in the n.o. solanaceæ / by James M. Petrie. Source: Wellcome Collection.

    17/58 page 127
    (£) The solution was diluted to 1 part of residue in 500 normal saline (1 in 1000 alkaloid), and when one drop of this was in- stilled into the eye of a dog, wide dilatation was produced in about 20 minutes. The alkaloid was therefore of the midriatic group. Evidence was thus obtained from these results that the alkaloids assumed to be non-volatile, had distilled over in small quantities, under the conditions stated. The next step, there- fore, was to ascertain the behaviour of pure atropine, when treated in the same way. xvi. Control experiment.— Method :—Pure atropine sulphate solutions with excess of lime, with and without sawdust, were distilled in a current of steam, from a flask fitted with a Kjeldah] spray-trap. At the end of each hour, the distillate which reacted alkaline to litmus, was shaken out with chloroform. The chloroform extract was then washed and dried, and the solvent distilled off. The residues were weighed and titrated, and afterwards examined, Results :—Very erratic results were obtained. In some, the amount of residue decreased to nothing in the five successive hours. In others, they varied much, even increasing at the end. In general, a total weight of 20mgs. was obtained after five hours. This yield was apparently independent of the amount of alkaloid taken, which was between 0:1 and 1‘(0mg. The addition of sawdust did not alter the result. All the residues contained alkaloid. When a distillate, without previous neutralisation, was evaporated in an open basin over a bunsen flame, the residue contained only a trace of alkaloid. (a) By titration of these residues as in the previous series, the amount of alkaloid (as atropine) in five hours’ distillation was ll mgs. If the latter be taken as representing the actual amount of alkaloid in each total distillate, then the alkaloid has distilled over under the conditions of these experiments at a rate of 2mgs. per hour. From these titrated solutioris, the alkaloid was recovered and examined,
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