Copy 1, Volume 1

Animal chemistry with reference to the physiology and pathology of man / By Dr. J. Franz Simon. Translated and edited by George E. Day.

  • Simon, Johann Franz, 1807-1843.
Date:
1845-1846
Catalogue details

Licence: Public Domain Mark

Credit: Animal chemistry with reference to the physiology and pathology of man / By Dr. J. Franz Simon. Translated and edited by George E. Day. Source: Wellcome Collection.

    31/426 (page 11)
    xantho-proteic acid, a change which is not produced by the action of that reagent upon chlorod-proteic acid. Let us now revert to the undissolved residue, which ultimate- ly assumes a uniform composition expressed by the formula! C,H, N,O,. It is this which is first formed from protein by the influence of the oxygen of the atmosphere. The other sub- stance (tritoxide of protein) originates from it by the addition of another equivalent of oxygen. In this respect albumen and fibrin give different results. Albumen, without going through this preparatory change like fibrin, is at once converted into trit- oxide of protein by ebullition, the insoluble portion which re- mains being unaltered albumen. From the composition of this insoluble portion it has received the name of binoxide of protem. It exists ready formed in the buffy coat of the blood. Von Laer has obtained it from hair in the followmg manner. The protein is first thrown down by the addition of a little acetic acid to a solution of hair in potash. On the addition of a larger proportion of free acid, after the removal of the protein, another substance, previously in a state of solution, is thrown down. ‘This is the binoxide of protem. Von Laer describes it as a bright yellow precipitate. After being carefully washed and dried it forms a black, glossy resinous mass, which on being pulverized forms a dark amber- yellow powder. It is insoluble in water and alcohol, but dissolves perfectly in dilute acetic, hydrochloric, nitric, and sulphuric acids. It does not assume so strong a yellow colour as protein, when treated with nitric acid. Ferrocyanide and ferridcyanide of potassium, and acetate of lead precipitate it from its acid solutions. It is soluble in potash and ammonia. If the binoxide of protein be treated with chlorine there is formed, at a loss of one atom of nitrogen, and a gain of three of oxygen, a new substance € , H,, N, O,., to which no name has yet been assigned. In order to obtain these products of oxidation of protein by boiling fibrin in water, it is essentially necessary that there should be free access to the atmospheric air.