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510 DIGESTION.
Besides the enzymes which have been discussed in connection with
the pancreatic juice, the gland also contains others, among which can be
mentioned the enzyme which, according to Stoklasa and his collab-
orators, occurs principally in organs and tissues and which decomposes
sugar into alcohol and carbon dioxide, like zymase. Opinions as to the
importance of the pancreas for glycolysis are diverse, and we therefore
refer the reader to what has been previously stated on this subject in
Chapter VII, pages 407 and 408.
V. THE CHEMICAL PROCESSES IN THE INTESTINE.
The action which belongs to each digestive secretion may be essen-
tially changed under certain conditions by being mixed with other
digestive fluids for various reasons, and also by the action of the
enzymes upon each other; 1
and since the digestive fluids which flow
into the intestine are mixed with still another fluid, the bile, it will be
readily understood that the combined action of all these fluids in the
intestine makes the chemical processes going on therein very complicated.
As the acid of the gastric juice acts destructively on ptyalin, this
enzyme has no further diastatic action, even after the acid of the gastric
juice has been neutralized in the intestine. Roger and Simon 2
claim
to have observed in saliva made inactive by the gastric juice, a reac-
tivation caused by the pancreatic juice, but these investigations do
not seem to be fully conclusive. The bile has, at least in certain animals,
a slight diastatic action, which in itself can hardly be of any great
importance, but which shows that the bile has not a preventive, but
rather a beneficial influence on the energetic diastatic action of the pan-
creatic juice. Several experimenters 3
have observed a beneficial action
of the bile on the diastatic action of the pancreas infusion. To this
may be added that the micro-organisms which habitually occur in the
intestine and sometimes in the food have partly a diastatic action and
partly produce a lactic-acid and butyric-acid fermentation. The
maltose which is formed from the starch seems to be converted into
glucose in the intestine. It seems conclusively that the cellulose cannot
be digested in the organism of the dog.4 Lohrisch found that on an
average of 50 per cent of the introduced cellulose and hemicellulose was
digested in human beings and yielded the corresponding sugar. That
1
See Wr6ble\vski and collaborators, Hofmcister’s Beitrage, 1.
2
Compt. rend. soc. biol., 02.
3
Martin and Williams, Proceed, of Roy. Soc, 45 and 48; Bruno, footnote 2, p.
502; Buglia, Bioch. Zeitschr. 25.
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