Studies on the proteids of rye and barley and on the chemical nature of diastase.

  • Thomas Burr Osborne
Date:
[1893]
Catalogue details

Licence: Public Domain Mark

Credit: Studies on the proteids of rye and barley and on the chemical nature of diastase. 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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    extracted with alcohol and ether. It was then dissolved in acetic acid and fractionally precipitated with potash. He states the composition of the substance as: Carbon 53.61 Hydrogen Nitrogen 16.84 Sulphur - 5-50 Oxygen 22.26 100.00 The gluten-casein was obtained by extracting the rye meal directly with very dilute potash-water, precipitating with acetic acid and washing with water, alcohol and ether. Two prepara- tions were made and gave as an average the following figures on analysis: Carbon 62.14 Hydrogen. C.93 Nitrogen - 16.38 Sulphur - 1.06 Oxygen — 23.49 100.00 Sidney Martin* states that wheat, rye and barley contain a globulin substance similar in properties to animal myosin, being soluble in 10-15 per cent, sodium chloride solutions, precipitated therefrom by saturation with sodium chloride and with magnesium sulphate and coagulating at 55° to 60°. This globulin is precip- itated by dialysis and thereby is converted into the albuminate form. It is very evident from the foregoing summary of previous work that we have no satisfactory knowledge of the rye-proteids. In presenting the results of my investigation the subject may be most conveniently discussed under the following heads : A, proteids soluble in water, B, proteids insoluble in water but soluble in saline solutions, C, proteids insoluble in water and in saline solutions and soluble in alcohol, and, D, proteid insoluble in water^ saline solutions, or alcohol but soluble in dilute alkalies. A, Proteids soluble in Water. Leucosin. Proteose. The proteids soluble in water are best examined in extracts made in the first instance with 10 per cent, sodium chloride solu- tion from which subsequently the soluble salts have been removed * Jour. Physiol., Vllf, viii.
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