Research into the chemical processes in the small intestine of man / by Allan Macfadyen, M.D. Ed., M. Nencki, M.D., and N. Sieber, M.D.

  • Macfayden, Allan, 1860-1907
Date:
[1891?]
Catalogue details

Licence: Public Domain Mark

Credit: Research into the chemical processes in the small intestine of man / by Allan Macfadyen, M.D. Ed., M. Nencki, M.D., and N. Sieber, M.D. Source: Wellcome Collection.

    16/44 (page 402)
    liquid. They were easily soluble in water, and gave all the reactions of succinic acid. The weight of the remainder, after complete extrac¬ tion with ether, chloroform, and alcohol, was 201 grammes. Thus the dry intestinal contents yielded 13*3 per cent, of soluble sub¬ stances. The watery extract, condensed to a syrup, gave neither leucin nor tyrosin. It consisted chiefly of sugar and peptones. We will not positively assert that leucin and tyrosin are not formed out of proteids in the small intestines by the action of the pan¬ creatic juice. If, however, these two substances do arise in the small intestine, their amount must be very small and their absorption very rapid. Our investigations show that in the small intestine the pro¬ teids are not, or only in very small quantity, decomposed by the bacteria. The faintly acid reaction of the intestinal contents suggested, however, the possibility of a decomposition of the carbohydrates through their agency. The presence of lactic and acetic acid also favoured this assumption. Microscopical preparations of the discharge abundantly proved that micro¬ organisms were present in great number, and our next task was to isolate the microbes in pure cultures, with a view of testing their action on proteids and carbohydrates. The opening of the fistula was always kept aseptic, and the woman was in a private room and separated from the other patients. We were, therefore, able to carry out our bacteriological investi¬ gations under favourable conditions, and to make the inocula¬ tions in a quiet atmosphere. The patient by coughing was able to move the food-mass downwards, and to eject a portion from the mouth of the fistula. With a sterilised platinum loop it was easy to reach the lumen of the intestine, and to remove portions of the contents before they came in contact with the air. At times the discharge was so abundant that we could collect it directly in a sterile glass vessel, which was applied closely to the mouth of the fistula. The further investigation was carried out as follows. Coloured and uncoloured preparations of the fresh discharge were examined microscopically, in order to obtain a preliminary notion of the bacterial forms present, and their relative number. Portions of the intestinal contents were well mixed with liquefied gelatine (10 per cent.) and agar (1*5 per cent.). From these Esmarch “ roll-plates” were made in 5 to 6 dilutions. The gelatine and a portion of the agar-plates were kept at 18° to