The physiology of the carbohydrates : an epicriticism / by F.W. Pavy.

  • Pavy, F. W. (Frederick William), 1829-1911.
Date:
1895
Catalogue details

Licence: Public Domain Mark

Credit: The physiology of the carbohydrates : an epicriticism / by F.W. Pavy. Source: Wellcome Collection.

Provider: This material has been provided by University of Bristol Library. The original may be consulted at University of Bristol Library.

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    substance obtained from albumin was found to yield, when heated with 10 per cent, sulphuric acid, a solu- tion having cupric oxide reducing properties, and also possessing several other characters in common with a solution of ordinary glucose. These characters have been already fully described by Dr. Pavy in the work referred to ; but, in order to render this portion of the subject quite clear, I propose to give here a brief summary of them. If the cupric oxide reducing solution obtained from proteid matter is freed from sulphuric acid by means of barium carbonate, and the filtrate evaporated to dryness, a residue is left which presents the appearance of a sugary extractive, and has a pronounced baked- sugar odour. A solution of the substance darkens in colour on being boiled with alkalis (Moore's test); it dissolves hydrated copper oxide in the presence of excess of alkali (Trommer's test) ; and gives a strong neat sugar reaction (reduction) with Fehling's solu- tion. The substance also gives the furfuraldehyde reaction with concentrated sulphuric acid and phenols. It should here be mentioned that Dr. Pavy also finds that when egg albumin is boiled with 10 per cent, sulphuric acid direct, the cupric oxide reducing sub- stance may be formed in a single operation. Foremost among the reactions exhibited by the cupric oxide reducing substance from proteid matter should, however, be mentioned its ability to yield a crystalline compound when heated with phenylhy- drazine acetate. This crystalline compound, more-