The proteids of the egg yolk.

  • Osborne, Thomas B. (Thomas Burr), 1859-1929.
Date:
[1900]
Catalogue details

Licence: In copyright

Credit: The proteids of the egg yolk. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

    2/10 (page 340)
    dilution, soon settled as a clear, transparent layer, from which the clear solution, c, was decanted completely. The proteid was readily and completely soluble in 10 p. c. brine to a perfectly clear pale yellow solution, which, when dialyzed until wholly free from chlorides, yielded the proteid in spheroids that sub- sequently united to a semi-solid mass. The latter was filtered out, washed thoroughly with water and with alcohol, and dried over sulphuric acid, giving 32.1 grams of preparation 2. The solu- tion, c (decanted from the precipitate produced by dilution that yielded 2), was treated with 1,000 cc. more water. This caused a precipitate which within two hours formed a semi- fluid deposit. From this the solution d was decanted, and the deposit dissolved in brine yielding a perfectly clear solution, which was dialyzed until free from chlorides. The proteid thus precipitated was filtered out, washed with absolute alcohol as long as anything could be removed thereby and then dried over sulphuric acid, giving preparation 3, weigh- ing 16.5 grams. The solution, d, was dialyzed free from chlorides, the precipi- tated spheroids were filtered out, washed with absolute alcohol and dried over sulphuric acid, making 5 grams of preparation 4. The solution, page 339, filtered after forty-eight hours’ dialysis from the substance that yielded the foregoing prepara- tions, was further dialyzed until almost all its dissolved proteid had separated. The precipitate thus produced was filtered out, dissolved in brine and the solution shaken out three times with ether. On shaking out the third time, the solution suddenly changed to an opaque jelly. This was then placed in a dialyzer, and when all the salt had been removed, the insoluble proteid was washed with absolute alcohol until everything soluble therein was extracted. Dried over sulphuric acid, this preparation, 5, weighed 75 grams. All these preparations were dried at 110° and analyzed with the following results: 1 2 3 4 5 Carbon 50.82 51.21 51.10 50.69 50.48 Hydrogen 7.11 7.07 7.21 7-o6 7-H Nitrogen 16.04 16.ii 16.23 16.40 i5-50 Sulphur I.II 1.05 1.00 1.05 1.02 Phosphorus 0.91 0.81 0.79 1.20 0.96 Ash . 2.37 2.49 1.56 3.23 3-19 P,0» in Ash r.65 r.79 2.30 2.15