3. Results and discussion
3.1. Experimental data
Empirical (symbols) and predicted (dash lines) hydrolysis curves for horse ...
Empirical (symbols) and predicted (dash lines) hydrolysis curves for horse mackerel protein with mixtures of subtilisin and trypsin. (a) Influence of the initial substrate concentration (g/L) at 47.5 °C and CHIR265 enzyme mixture ratio 1:1. (b) Influence of the temperature at an initial substrate concentration of 5 g/L and an enzyme mixture ratio 1:1. (c) Influence of the composition of the enzyme mixture at 5 g/L and 47.5 °C.
The influence of the reaction temperature on the hydrolysis curves is depicted in Fig. 1b, where the initial substrate concentration and the percentage of subtilisin in the enzyme mixture were fixed at 5 g/L and 50%, respectively. It can be seen that the increase of reaction temperature plays a detrimental effect on the final DH. This behavior is a trade-off between the solubility of the substrate protein and the intervals of stability of the enzymes employed. Effectively, higher temperatures favor the solubility of the substrate, and hence, the availability of peptide bonds. By contrast, subtilisin is stable at high temperatures (maximal activity at 50 °C) while trypsin presents an optimal activity at 37 °C .