Peptides isolated from fish protein hydrolysates can be used in food systems as functional ingredients of specialized food products. A study was conducted to determine the fractional composition and amino acid sequence of the protein of the pink salmon innards. The crushed innards of chilled pink salmon were used as an object of research. Extraction methods based on the use of ammonium sulfate were used to isolate proteins. The amino acid sequence in a peptide was determined by mass spectrometric method. Two protein fractions were isolated in the chilled pink salmon innards. The amino acid sequence of fraction 1 was 194 amino acids, and fraction 2 was 134 amino acids. The sequences contain certain repetitive amino acid motifs, in particular CC, EE, YY, VV, PP, AA, LL, NM, PPE, CYR and others, indicating the presence of structural or functional areas in the protein composition that may have significant biological effects with target cells. For further isolation and identification of biologically active peptides from amino acid sequences of protein fractions, it is advisable to carry out a predetermined prediction of protein hydrolysis (in silico) followed by peptidomic analysis based on mass spectrometry. It will allow monitoring the content of already known peptides in fractions, but at the same time using it as a tool for the discovery of new bioactive peptides.

Tikhonov Sergey L. , Tikhonova Natalya V.

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