Further observations on myohaematin and the histohaematins / by C.A. MacMunn.

  • MacMunn, Charles Alexander, 1852-1911.
Date:
[1887]
Catalogue details

Licence: Public Domain Mark

Credit: Further observations on myohaematin and the histohaematins / by C.A. MacMunn. 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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    bands of tlie original solution, and changed in the same manner with sulphide of ammonium, but when heated to a certain point the bands disappear, as they do in muscle itself. Incinerated the precipitate showed the presence of iron, and it also contained sulphur, besides carbon, oxygen, and nitrogen. Whatever precipitates the proteid out of solution also precipitates the colouring matter; and from the coagulum no solvent that I have used will extract the colouring matter; hence pigment and proteid are closely united. In fact, myohaematin appears to be a coloured proteid. On certain Crystals observed in Solutions obtained as above.—When muscle-juice obtained as described is concentrated in vacuo over sulphuric acid crystals separate out, which belong to the rhombic system^ and are coloured yellow or yellowish-red; each crystal when large enough showing the bands of the m other solution. They readily dissolve in water, the solution being precipitated by heat and by absolute alcohol; these crystals were incinerated and also yielded traces of iron. Hence I was inclined to believe that they must have been crystals of myohae- matin; but subsequent experiments showed that this is not the case. In colourless muscle-juice from the rabbit I observed similar crystals and these shoAved no absorption bands whatever. Subsequently I found that I could deprive coloured crystals of their colour, while at the same time they lost their absorption bands, by washing them with water containing enough rectified spirit to keep them from dissolving; and when thus prepared their aqueous solution was no longer precipitated by heat or alcohol, and boiling with Millon's reagent gave a negative result. Why did crystals from coloured juice give a spectrum and proteid reactions, and why did their ash contain iron ? Simply because each crystal as it formed became coated with a film of coloured proteid to which these reactions were due. When the colourless crystals were dried in vacuo over H^SO^ they effloresced, each crystal breaking down into a white powder. Finally I proved them to be crystals of kreatin, and doubtless the muscle-juice obtained as I have described may be found useful for the demonstration of kreatin. By following Hoppe-Seyler's directions'* I changed them into kreatinin and obtained the very characteristic crystals of the combination of zinc chloride and kreatinin by treatment with the latter reagent and allowing the solution to stand some hours. ' Oblique ihombic columns, ...belonging to the monoclinic system. ♦ Iluiidbucli ficr PUijs. tind Path. Chan. Anal, vierte Auflagc, S. 178.