QUANTITATIVE COMPARISON OF CASEIN AND RAPESEED PROTEOLYSIS BY PANCREATIN

The problem of quantitative comparison of kinetic curves was solved fo r casein and rapeseed pancreatin hydrolysis in a membrane reactor, whi ch ensured the measurement of proteolysis kinetics for the products wi th a molecular weight of less than 1000. Coordinates were derived whic h provided good linearization of kinetic curves and the determination of relative rate constants irrespective of reagent concentrations, E(0 )/S-0 ratio and time intervals of kinetic measurements. When the relat ive rare constants of the release of the individual amino acid residue s in the low-weight proteolysis products were compared trypsin-depende nt constants (for Lys and Arg residues) were found to be two times les s far rapeseed than for casein, and chymotrypsin-dependent constants ( for Tyr and Phe residues) were approximately 1.3 times higher for rape seed than for casein. Statistical analysis demonstrated that the distr ibution of constants was narrower for rapeseed than for casein. Differ ences between target (Arg, Lys, Tyr and Phr) and non-target constants of release in the form of peptides and free amino acids, or in the for m of free amino acids only, were attributed to the differences in the peptide bond masking for casein and rapeseed proteins. Computer simula tion of proteolysis kinetics was performed by PROTEOLYSIS program pack age to confirm the dependence of rate constant distribution on the sta te of masking.