(743, 
independently, nor that of increasing the fat-splitting action of the 
pancreatic juice, 
e. Action on albumose. 
So far, our investigations regarding the action of intestinal juice 
on proteids had been carried out with coagulated white of egg, 
though we also performed a few confirmatory experiments with 
fibrin. No attention had however been paid to liquid white of egg. 
Therefore we have aiso made experiments with that substance, but as 
this investigation is at present incomplete we postpone any further de- 
scription of it for a later communication. We will, however describe 
in a few words, some experiments in reference to the influence of in- 
testinal juice on albumose. The results obtained were striking; 
namely that albumose (the so-called peptonum siccum of com- 
merce) was wholly transformed in a powerful way by intestinal juice 
into a substance or substances which give no biuret reaction, and 
are not precipitable by saturation with ammonium sulphate. 
In order to ascertain whether the agent reponsible for this action 
is the same as or different from zymolysine, an attempt was made 
to separate the two actions by fractional heating, and with perfect 
success. After heating for 2 hours to 59°, the power of the intestinal 
juice to transform albumose had disappeared, but that of liberating 
trypsin from zymogen was still present nearly unimpaired. 
By keating the intestinal juice first to 59° and then to 67°, the 
latter action was also lost and by heating at once to 67°, both 
disappeared at the same time. 
After having ascertained these facts, a paper written by O. COHNHEIM’) 
and published quite recently came into our hands. This writer had 
stated that a substance exists in the intestinal mucous membrane 
of dogs and cats, which is able to decompose peptone and also 
albumose and which he has named “erepsin’’. At the end of his paper 
CoHNHEIM points out, that he obtained this ferment from the finely- 
divided intestinal mucous membrane, but that the question is still 
open whether the substance is also present in the intestinal juice; 
in other words, whether the erepsine-action takes place intracellularly 
or extracellularly. Our researches prove undoubtedly thut the erepsine 
is secreted and contained in the intestinal juice. 
What the substances are which are produced by the influence 
1) ©. Counuem. Zeitschr. f. physiol. Chemie 33. 1901. S. 452. 
49 
lroceedings Royal Acad. Amsterdam. Vol. IV. 
