title: [Bitter peptides of casein isolated by hydrolysis with alpha-chymotrypsin and trypsin (author's transl)].
abstract: Two bitter peptides, H-Phe-Tyr-Pro-Glu-Leu-Phe-OH (I) and H-Val-Glu-Val-Phe-Ala-Pro-Pro-Phe-OH (II) were isolated from casein, hydrolyzed by alpha-chymotrypsin. The hexapeptide is cleaved by thermolysine between Glu and Leu. The two fragments are bitter too. A bitter dodecapeptide (III) was obtained 20 min hydrolysis of casein with trypsin. On account of amino acid composition and N-terminus peptide III is probably identical with a peptide from a 12 hrs hydrolyzate, described in 1970 by Matoba. The peptides I and III have equal taste tresholds in the range of 0.08-0.10 muM/ml.
mesh_terms: D002364:Caseins / Q000032:analysis*; D002918:Chymotrypsin; D006868:Hydrolysis; D008722:Methods; D010455:Peptides / Q000302:isolation & purification*; D013649:Taste; D014357:Trypsin
chemical_list: D002364:Caseins; D010455:Peptides; D002918:Chymotrypsin; D014357:Trypsin
vernacular_title: Bittere Peptide aus Casein nach Hydrolyse mit alpha-Chymotrypsin und Trypsin