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.

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    improbable. All that we can conclude is that the embryo con- tains the different protein substances described, together with nucleic acid, and that these may unite to form a number of different compounds according to the conditions which prevail at any given time. THE PROTEIDS OE THE EGG YOLK. By Thomas B. Osborne and George E. Campbell. The yolks of a large number of freshly laid hen^s eggs were broken up by straining through a sieve and mixed with an equal volume of saturated pure sodium chloride brine. A some- what turbid solution resulted, which was shaken out with about one-third its volume of ether, containing a little alcohol. After standing one night, a clear reddish ethereal layer separated, leaving the pale yellow aqueous solution almost clear. After shaking out a second time with ether the aqueous solution was dialyzed for forty-eight hours, whereupon a large quantity of proteid separated in spheroids which united to a salvy mass. This was freed, as far as possible, from the liquid, by drain- ing on filters, redissolved in lo p. c. brine and its solution dialyzed for three days. From the semi-solid mass thus obtained the liquid was decanted and the precipitate dissolved n ^ transparent gummy substance (lecithin?) remained undissolved which rendered filtration very difficult. By filtering under considerable pressure on a thick- layer of paper pulp about 700 cc. of perfectly clear filtrate a and 2,000 cc. of very nearly clear filtrate, h, were obtained. The atter b, was dialyzed for four days, when the large deposit was filtered out and treated with about a liter of salt solution A gelatinous, almost pasty mixture resulted, which was shaken out with ether. The two liquids at once separated, the ethereal bemg dear and strongly yellow in color and the aqueous almost Lr and not at all gummy. Shaken out three times ore with ether, this aqueous solution became suddenly opaque 2 sorfr- fro” chlorides! Irtr ether and preparation 1, weighing 6o grams. The cW solution, a (700cc,), was diluted with three volumes of distilled water, and allowed to stand over night at a temperature of 6». The proteid, which had separatfd on