Diseases of the intestines and peritoneum / by Hermann Nothnagel ; edited, with additions by Humphrey D. Rolleston ; authorized translation from the German, under the editorial supervision of Alfred Stengel.
- Hermann Nothnagel
- Date:
- 1904
Licence: Public Domain Mark
Credit: Diseases of the intestines and peritoneum / by Hermann Nothnagel ; edited, with additions by Humphrey D. Rolleston ; authorized translation from the German, under the editorial supervision of Alfred Stengel. Source: Wellcome Collection.
Provider: This material has been provided by the Francis A. Countway Library of Medicine, through the Medical Heritage Library. The original may be consulted at the Francis A. Countway Library of Medicine, Harvard Medical School.
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![The amylolytic enzyme of pancreatic diastase acts in a similar man- ner to ptyalin, and possesses the power of converting boiled starch into maltose very rapidly at body-temperature. In addition small quantities of dextrin and traces of dextrose are formed. The efficiency of the fermentative action depends largely upon whether the reaction is acid or alkaline. According to V. Hofmeister, the maximum diastasic action is attained in the presence of 0.05 per cent, of acetic acid and 0.03 per cent, of lactic acid. According to Kr5ger, 1 gram of a dog's pancreatic juice converts 4.6 grams of starch into sugar (and dex- trin) in thirty minutes. Cane-sugar and inulin are unaltered by pancreatic juice. According to Zweifel and Korrwin, this ferment is absent from the pancreas of new-born children. Ewald, on the other hand, succeeded in demonstrating its presence in the pancreatic juice of a puppy three days old. [H. M. Vernon finds that ptyalin and the amylolytic ferment of the pancreas are different and not iden- tical bodies, and that the pancreatic amylolytic ferments or diastases of various animals are different bodies. It appears that pancreatic diastase is a single definite chemic substance, and thus differs from trypsin and pancreatic rennin. He confirms Chittenden and Griswold's obser- vations that the activity of pancreatic diastase is increased by very small quantities of acids.—Ed.] The Upolytie ferment (steapsin) has so far not been isolated. It possesses the power of splitting neutral fats into fatty acids and gly- cerin (Bernard and Berthelot). CgHgOgRg (neutral fat) + SH^O == CgliPgHg (glycBrlu) + 3 (HOR) (fatty acid). Nencki has shown that other esters can also be saponified by this enzyme. The cleavage of the fat molecule occurs very slowly. Berthelot, for instance, allowed about 15 grams of pancreatic juice from a dog to act upon a decigram of monobutyrin, and found that it required twenty-four hours before the monobutyrin molecule was completely transformed into butyric' acid and glycerin. Blank allowed 50 grams of finely chopped ox's pancreas to act on 5 grams of mutton fat for twenty-four hours, and found that in one experiment 20.7 per cent., and in another experiment 20,4 per cent., were split up into glycerin and fatty acids. The fatty acids thus freed combine with the alkali present in the intestine to form soaps. This subsequently greatly aids in emulsifying the fats (Briicke, Gad), and in this way is said to promote their absorption. The proteolytio ferment was first clearly described by Kiihne, who called it trypsin. The first observations on the proteolytic ferment of the pancreas were made by Claude Bernard and Corvisart. Subse- quently numerous other workers have attempted to isolate the ferment in a pure state and have investigated its action on proteids (Danilewski, Hiifner, Kiihne, Low, and others). [The zymogen of trypsin was dis- covered by Heidenhain in 1875. H. M. Vernon found that trypsin was destroyed by sodium carbonate and showed grounds for the suppo- sition that trypsin is not a single substance, but that there is a series of trypsins of varying degrees of stability, the more unstable being destroyed first by sodium carbonate and the more stable slowly. He also believes](https://iiif.wellcomecollection.org/image/b21170010_0027.jp2/full/800%2C/0/default.jpg)
