Secretagogues and growth factors in fish and crustacean protein hydrolysates

The search for new molecules in fish protein hydrolysates is of great inter est in animal feeding as it is in aquaculture, fertilizer, cosmetic, and ph armacologic domains. Different sources of hydrolysates such as shrimp waste (Pandalus borealis), cod (Gadus morhua) head, and head and viscera of sard ine (Sardina pilchardus), obtained after hydrolysis or autolysis, were test ed on fibroblast cell cultures and by gastrin radioimmunoassay. The level o f hydrolysis seems to play an important role in the presence of biological peptides. Elution profile on a gel filtration Sephadex G-50 column was used to estimate the degree of hydrolysis of the fractions studied. Growth-fact or-like activities were found in less-hydrolyzed fractions. Conversely, the most-hydrolyzed fractions showed gastrin and cholecystokinin immunoreactiv ity.