The hydrolysiis of gliadin from rye / by Thomas B. Osborne and S.H. Clapp.

  • Thomas Burr Osborne
Date:
[1908]
Catalogue details

Licence: In copyright

Credit: The hydrolysiis of gliadin from rye / by Thomas B. Osborne and S.H. Clapp. 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.

    4/8 page 497
    Fraction iv.—The yield of phenylalanine hydrochloride from this fraction was 11.62 gm. The free substance was employed for the analysis. Carbon and hydrogen, 0.1347 gm. subst. gave 0.3226 gm. C02 and 0.0833 gm- HoO. Calculated for C9Hu02N == C 65.45 ; H 6.66 per cent. Found . . . . = C 65.32; H 6.87 “ “ There were further isolated from this fraction 0.87 gm. of pure aspartic acid as the barium salt. The substance crystallized in the characteristic form, and reddened but did not decompose at 300°. Unfortunately no elementary analysis was obtained, as the prepara- tion was lost. The filtrate from the barium aspartate was freed from barium and examined for glutaminic acid. There were isolated 9.89 gm. of the hydrochloride. The free substance decomposed at about 203 °. Carbon and hydrogen, 0.2687 gm. subst. gave 0.4049 gm. C02 and 0.1524 gm. HoO. Calculated for C5H804N = C 40.81 ; H 6.12 per cent. Found . . . . = C 41.09; H 6.29 “ “ In the filtrate from the glutaminic acid hydrochloride no copper salt of aspartic acid could be obtained. There was further isolated from Fraction IV 0.2 gm. of pure serine. The substance browned at about 2150 and decomposed at about 238°, with effervescence, to a brownish mass. Carbon a?id hydrogen, 0.1212 gm. subst. gave 0.1536 gm. C02 and 0.0790 gm. HoO. Calculated for C3H703N = C 34.29 ; H 6.67 per cent. Found . . . . =C 34.56: H 7.24 “ _ “ Tyrosine. Fifty grams of rye gliadin, equal to 42.98 gm. moisture, fat, and ash free, were hydrolyzed by heating with a mixture of 150 gm. sulphuric acid and 300 c.c. water for two and a half hours on a water bath and boiling for twelve hours on an oil bath. After removing the sulphuric acid with an equivalent quantity of baryta and boiling out the barium sulphate several times with water the solution was concentrated to crystallization. After standing over night the substance that had separated was recrystallized from
    digitised image 1
    digitised image 2
    digitised image 3