The poisonous constituent of the bark of Robinia pseudacacia / by Frederick B. Power.

  • Frederick Belding Power
Date:
[1913]
Catalogue details

Licence: In copyright

Credit: The poisonous constituent of the bark of Robinia pseudacacia / by Frederick B. Power. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

    5/8 page 341
    Am. Jour. 1*11arm. } August, 1918. j Bark of liobinia Pseudacacia. 34i Power’s statements are not valid for the robin of Robinia bark prepared by me (Robert) and preserved in a dry state. It does not hydrolyze sinigrin even by its action for two days in an incu- bator and does not otherwise possess the property of hydrolyzing glucosides. It also has no coagulating effect on milk.” It is exceedingly unfortunate that Professor Robert should have given such prominence to the results of experiments from which thoroughly incorrect inferences are liable to be drawn, especially by those who cannot conveniently repeat them, and he does not seem to have considered it necessary to ascertain the cause of his failure to obtain the results recorded by me. As the subject is one of considerable importance, I have deemed it desirable to present such facts as are believed to be sufficient to prove the incorrectness of Professor Robert's conclusions, and to substantiate in every re- spect the accuracy of the statements previously recorded by me regarding the toxic action and other properties of the protein of Robinia bark. In the first place it was noted in my paper on this subject in 1890 that a decoction made by boiling ioo grammes of the bark with water was taken without any ill effect or any perceptible action, whereas a cold infusion of about 5 grammes of the bark was in one instance so violent in its action as nearly to prove fatal. It was thus evident that the activity of the poisonous substance was destroyed at the temperature of boiling water, and this observation suggested not only the protein nature of the substance but also the method subsequently employed for its isolation. Moreover, the protein material, as precipitated bv alcohol from the liquid obtained bv macerating the ground bark with cold water, when collected, washed with alcohol, and dried in a vacuum or over sulphuric acid, possessed the same poisonous properties as the bark. When ad- ministered to a large dog in an amount representing about 30 grammes of the bark, it caused severe vomiting, which continued at intervals for several hours, and a considerably smaller quantity was not without effect. A solution of the same substance, when heated sufficiently to coagulate the protein, was quite devoid of activity. As the above experiments had been conducted with a bark collected by myself at Madison, Wisconsin, it may be noted t at some years subsequently a quantity of protein material was prepared from Robinia bark collected in France. This protein material, when isolated by the simple method above described, pos-
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