TOXICOLOGY AND PHARMACOLOGY 369 



Ferments. 



Ferments are much reduced in activity by the salts of heavy 

 metals. Since a parallelism has been shown to exist between the 

 toxicity of colloidal metals and that of their salts, it was expected 

 that the colloidal metals would exert a powerful action on ferments. 

 It is a remarkable fact that the colloidal metals proved to be more or 

 less indifferent. 



The digestion of albumin by pepsin, the digestion of gelatin by 

 trypsin, the coagulation of milk by rennin, the cleavage of fat by 

 pancreatic steapsin and lipase, the fluidification of starch by pan- 

 creatin and takadiastase were uninfluenced by colloidal silver (see M. 

 ASCOLI and G. IZAR*). 



L. PINCUSSOHN* examined the following substances for their in- 

 fluence on digestion with pepsin: chemically prepared hydrosols of 

 silver, selenium, gold, copper, bismuth, mercury (Hyrgolum) and 

 arsenic; and electrically pulverized preparations of silver, gold, 

 platinum, mercury and bismuth. In no case was the activity of 

 pepsin increased, but it was diminished by large doses, and least in 

 the case of hydrosols obtained by electrical pulverization. 



E. FILIPPI * was unable to obtain any effect with colloidal metals 

 (Au, Hg, Cu, Ni, Pd) upon fermentation in the case of yeast, pepsin, 

 trypsin or rennin. 



Small quantities of silver hydrosols, on the contrary, activate the 

 diastatic ferment of the liver and of the blood serum. 



According to H. J. HAMBURGER, the action of staphylolysin, the 

 hemolytic excretion of staphylococci, is inhibited by collargol. Ac- 

 cording to W. WEICHARDT, colloidal platinum and palladium neutral- 

 ize fatigue poisons. 



In vitro, C. FOA and A. AGGAZZOTTI were unable to demonstrate any 

 action of silver hydrosol upon toxins, but they could if it was in- 

 jected into the circulation immediately after the toxin. 



O. GROS and J. M. O'CONNOR obtained divergent results for the 

 decrease in the strength of tetanus and diphtheria toxin produced by 

 collargol. 



Autolysis. 



In marked contradiction to the inactivity of silver hydrosol on 

 most ferments is the very considerable influence of metal hydrosols on 

 the enzymes of autolysis. If any organ, the stomach, liver, spleen, etc., 

 is kept, especially if kept at body temperature, changes occur in it which 

 finally lead to a softening and decomposition characterized by a more 

 or less extensive cleavage of the albumins, nucleins, etc., involved. 



This decomposition occurs even though the organ is absolutely 



