ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

The hydrolytic cleavage of protein. IV. The formation and isolation of cystine by hydrolysis of keratin with hydrochloric acid

V. Mareček and A. Trubnyj

Forschungsinstitut für Öle und Fette in Prag

Abstract: cf. C.A. 42, 4216i; 49, 1125a. Splitting off of cystine (I) and tyrosine by hydrolysis of keratin by HCl was studied quantitatively. It was found that the optimum amts. of I in soln. can be obtained by a short reaction time, up to 12 hrs., at 20% HCl and 110°. Lower temps. and longer reaction time are not favorable for I formation in the hydrolyzate. By chromatographic analysis under these conditions the amt. of I is quite high, but owing to a lower amt. of N in the primary amino groups and to higher amts. of decompn. products the conditions for the isolation of I are not favorable. A certain excess of HCl for the formation of I is desirable, but a concn. higher than 25% HCl causes the destruction of I. The isolated needles, were not the inactive form of I because S was not present, but chromatographic analysis shows tyrosine.

Full paper in Portable Document Format: 102a130.pdf (in Czech)

Chemical Papers 10 (2) 130–134 (1956)