Marine Collagen Peptides from the Skin of Nile Tilapia (Oreochromis niloticus): Characterization and Wound Healing Evaluation.

Burns can cause tremendous economic problems associated with irreparable harm to patients and their families. To characterize marine collagen peptides (MCPs) from the skin of Nile tilapia ( Oreochromis niloticus ), molecular weight distribution and amino acid composition of MCPs were determined, and Fourier transform infrared spectroscopy (FTIR) was used to analyze the chemical structure. Meanwhile, to evaluate the wound healing activity, in vitro and in vivo experiments were carried out. The results showed that MCPs prepared from the skin of Nile tilapia by composite enzymatic hydrolysis were composed of polypeptides with different molecular weights and the contents of polypeptides with molecular weights of less than 5 kDa accounted for 99.14%. From the amino acid composition, the majority of residues, accounting for over 58% of the total residues in MCPs, were hydrophilic. FTIR indicated that the main molecular conformations inside MCPs were random coil. In vitro scratch assay showed that there were significant effects on the scratch closure by the treatment of MCPs with the concentration of 50.0 μg/mL. In the experiments of deep partial-thickness scald wound in rabbits, MCPs could enhance the process of wound healing. Therefore, MCPs from the skin of Nile tilapia ( O. niloticus ) have promising applications in wound care.