A novel zinc-binding peptide identified from tilapia (Oreochromis niloticus) skin collagen and transport pathway across Caco-2 monolayers

Tilapia (Oreochromis niloticus) skin collagen hydrolysates (TSCHs) were obtained using Alcalase, Trypsin, and Protamex. Our results indicated that enzyme type, degree of hydrolysis, molecular weight distribution significantly affected the zinc-binding capacity TSCHs. Five peptides isolated purified via immobilized metal affinity chromatography reversed-phase high performance liquid chromatography. Their amino acid sequences LGPY, GFLGSP, FHGLR, LGYPGPKGSP, LRGLPGSVGEQ. Of these, peptide GFLGSP exhibited highest capacity. Fourier transform infrared spectroscopy demonstrated sites located at nitrogen atom group oxygen carboxyl GFLGSP. Scanning electron microscopy revealed surface morphology was changed after adding zinc. Furthermore, had strong stability during simulated gastrointestinal digestion. Caco-2 cell monolayer experiments can be transported paracellular pathway tight junctions transport pathway.