Influence of the hydrolysis process on the biological activities of protein hydrolysates from cod (Gadus morhua) muscle

Upgrading of fish protein through limited proteolysis of by-products and su rplus of the food industry generates peptides of interest to food formulati on, the animal feed industry and aquaculture. The hydrolysis process has be en studied in order to investigate the role of the limiting parameters. Hyd rolysates obtained under varying conditions of temperature, pH, time and en zyme concentration were tested on fibroblastic cell cultures and in gastrin radioimmunoassays. Several fractions were shown to contain biologically ac tive peptides such as growth factors or secretagogues (gastrin and cholecys tokinin). Under optimum conditions we obtained 160% stimulation of cell gro wth with only 25 mug ml(-1) hydrolysates, and about 0.25 pg gastrin-like pe ptides mg(-1) sample. The process of hydrolysis plays a key factor by exten ding the time of protein degradation in generating these molecules. (C) 200 0 Society of Chemical Industry.