ISSN print edition: 0366-6352
ISSN electronic edition: 1336-9075
Registr. No.: MK SR 9/7
Splitting off ammonia during protein hydrolysis with hydrochloric acid and the determination of intensity of splitting
Forschungsinstitut für Öle und Fette in Prag
Abstract: There is no direct relation between the amts. of aminodicarboxylic acids and the amt. of ammonia, which is contrary to findings of Osborne (O. and Harris, J. Am. Chem. Soc. 25, 323(1903); O et al., Am. J. Physiol. 23, 180 (1908)). The approx. ratio of both values in animal protein is 100:50 and in plant protein 100:100. In plant protein every free (not peptide-linked) carboxyl group of aminodicarboxylic acids is in the form of amide, in animal protein only one half of these groups are in that form. In splitting off ammonia by HCl the fastest reaction is the carryover of the total N into soln., followed immediately by ammoniacal N, and the slowest is the change of N into primary amino groups. After reaching the max. value of ammoniacal N, then the values of N in primary amino groups increases 3-4 times. On the basis of the findings a new formula for the intensity of splitting is given: [(amino N + ammoniacal N) × 100]/total N.
Full paper in Portable Document Format: 101a63.pdf (in Czech)
Chemical Papers 10 (1) 63–69 (1956)