On the nature, action, and therapeutic value of the active principles of tuberculin : an investigation / by William Hunter.

  • Hunter, William, 1861-1937.
Date:
1891
Catalogue details

Licence: Public Domain Mark

Credit: On the nature, action, and therapeutic value of the active principles of tuberculin : an investigation / by William Hunter. 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.

    4/43 (page 2)
    still less any injurious action on the organism, this process of purification has, he alleges, no practical advantage and only adds unnecessarily to the expense of its preparation* As regards the nature of this active principle, its complete precipitation by absolute alcohol points to it being of albu- minous nature, perhaps belonging to the class of bacterial poisons of that nature recently described by Brieger and Fraenkel under the name of “ toxalbumins.” It differs from these, according to Koch, in two important respects— first, in being able to withstand high temperatures without losing its poisonous properties; secondly, in dialysing quickly and easily through parchment membrane. Koch concludes therefore that it is not a toxalbumin; that its nature must be left for the present a matter for conjecture. He prefers to describe it as “ a derivative of albuminous bodies.” Comments on the Foregoing. This definition of it as a “ derivative ” of albuminous material leaves, in truth, the question of the chemical nature of this substance entirely open. I need hardly point out that it is as fitly applicable to any of the more remote derivatives of albuminous metabolism, such as tyrosin, leucin, or urea, as it is to the more immediate deri- vatives such as albumoses, or peptones ; and that it is equally applicable to such widely different classes, chemic- ally speaking, of bacterial products as toxalbumins on the one hand, and alkaloids or toxines on the other. I do not think that the description given by Koch of the behaviour of this hypothetical principle can possibly apply to any one chemical substance yet known to us. It is easy to understand an albuminous body being precipitated by absolute alcohol. But to no albuminous body, with the single exception of peptones, can the further statement possibly apply—that it is easily dialysable through parch'