A hydrolytic derivative of the globulin edestin and its relation to Weyl's albuminate and the histon group.

  • Osborne, Thomas B. (Thomas Burr), 1859-1929.
Date:
[1900]
Catalogue details

Licence: In copyright

Credit: A hydrolytic derivative of the globulin edestin and its relation to Weyl's albuminate and the histon group. 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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    of edestan was formed at once, and 70.46 per cent, after 20 hours’ contact. That the amount of edestan formed in a given time depends on the degree of ionization of the acid was shown by suspend- ing gram portions of neutral edestin in 6 cc. of water, adding 14 cc. of centinormal hydrochloric, phosphoric and acetic acids respectively, and, after frequently agitating for about 2 hours at 200, determining the amount of edestan formed in each. Table III.—Percentage of Edestan formed by Equivalent Quanti- ties of Different Acids Under the Same Conditions. HCI H3P04 H4c2°2 19.29 16.02 5.65 The solution of phosphoric acid used in this experiment contained 0.98 gram of H3P04 per liter, being made on the assumption that this acid behaves towards edestin as a mono- basic acid. The much smaller quantity of edestan formed by acetic acid, compared with that formed by hydrochloric acid, is in accord with the lesser ionization of this acid. c. Composition of edestan. Ten grams of a preparation of crystallized edestin chloride were suspended in water, in a glass stoppered bottle and 30 cc. of decinormal hydrochloric acid were gradually added. After the resulting clear solution had stood at the room temperature for about two hours, it was made neutral to phenolphthalein by adding 38 cc. of decinormal potassium hydrate solution, the 8 cc., in the excess of the 30 cc. of added acid being required to neutralize the acid originally combined with the edestin pre- paration. The curdy precipitate, that formed on neutralizing, was washed thoroughly with 10 per cent, sodium chloride solution and then with water, until chlorides were removed, and finally with absolute alcohol. Dried over sulphuric acid, this formed preparation 1, which weighed 6.82 grams. This experiment was repeated with another preparation of edestin chloride, the acid solution allowed to stand over night, at a temperature below io° and then 50 cc. decinormal potassium hydrate solution was added. Although this excess