RESUMO
: The search for new molecules in fish protein hydrolysates is of great interest in animal feeding as it is in aquaculture, fertilizer, cosmetic, and pharmacologic domains. Different sources of hydrolysates such as shrimp waste (Pandalus borealis), cod (Gadus morhua) head, and head and viscera of sardine (Sardina pilchardus), obtained after hydrolysis or autolysis, were tested on fibroblast cell cultures and by gastrin radioimmunoassay. The level of 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-factor-like activities were found in less-hydrolyzed fractions. Conversely, the most-hydrolyzed fractions showed gastrin and cholecystokinin immunoreactivity.
RESUMO
Regenerating-tissues of the starfish Asterias rubens were studied for the presence of growth factors liable to stimulate the proliferation of fibroblast and epithelial cells (3T3, BHK21 and Hela cells). As a first attempt to isolate growth factors, the extracts were fixed on heparin-affinity column and were eluted by 1-1.2 M NaCl. After separation on a Vydac C18 HPLC column. a fraction that stimulates the proliferation of fibroblast cells was isolated. It contained four different peptides, separated by electrophoresis, and for which the amino acid composition and molecular mass were determined. All the peptides were lysine rich and one presented an amino-acid composition comparable to basic-fibroblast growth factor (b-FGF) while its molecular weight was higher.
