Hydrolysis of the proteins of maize, Zea Mays / by Thomas B. Osborne and S.H. Clapp.

  • Osborne, Thomas B. (Thomas Burr), 1859-1929.
Date:
[1908]
Catalogue details

Licence: In copyright

Credit: Hydrolysis of the proteins of maize, Zea Mays / 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.

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    Nitrogen, 0.1897 gm. subst. required 2.5 c.c. 5/7 N—HC1. Calculated for C12H1202N2 = N 12.96 per cept. Found = N 13.17 “ “ Fraction iv. — From this fraction phenylalanine was removed as the ester in the usual way. The yield of the hydrochloride of phenylalanine was 29.11 gm. The free phenylalanine decomposed at about 270 0 and gave the following analysis: Carbon and hydrogen, 0.1150 gm. subst. gave 0.2773 gm- CO and 0.0699 gm. H20. Calculated for C9Hn02N = C 65.45 ; H 6.66 per cent. Found .... = C 65.76; H 6.75 “ “ The aqueous layer was saponified by warming with an excess of baryta on the water bath. The yield of aspartic acid isolated as the barium salt was 5 gm. Carbon and hydrogen, 0.2571 gm. subst. gave 0.^426 gm. C02 and 0.1252 gm. H20. Calculated for C4H704N = C 36.09 ; H 5.26 per cent. Found .... = C 36.34 ; H 5.41 “ “ The filtrate from the barium aspartate was freed quantitatively from barium, concentrated under reduced pressure, and saturated with hydrochloric acid gas. The yield of glutaminic acid, which separated after prolonged standing at o°, was 20.37 g‘m- The free glutaminic acid decomposed at about 20i°-202° with effervescence to a clear oil. From this fraction there were further isolated 3.94 gm. of air-dry copper aspartate, while no serine was obtained. Copper, o. 1135 gm. subst. (air dry) gave 0.0330 gm. CuO. Nitrogen, 0.5275 gm. subst. (air dry) required 2.7 c.c. 5/7 N—HC1. Calculated for C4H504NCu 4^ H20 = Cu 23.07 ; N 5.08 per cent. Found = Cu 23.23 ; N 5.12 “ “ The Residue after Distillation. The residue remaining after distillation of the esters weighed 84 gm. It was saponified with baryta and the glutaminic acid separated as the hydrochloride in the usual manner. The yield of glutaminic acid hydrochloride was 14.32 gm., which makes the