Preparation and properties of caffeic-chitosan grafting fish bone collagen peptide

In this study, a novel peptide grafted chitosan (CACS-FBP) with high peptide content, excellent moisture-absorption and moisture-retention abilities was prepared. Caffeic acid (CA) was used to modify chitosan, the highly water-soluble intermediate further reacted with fish bone collagen peptide to obtain the final product, and the synthesis of CACS-FBP was confirmed by the Fourier transform infrared spectroscopy (FT-IR), NMR, and UV-vis. The single-factor experiments indicated that the degree of substitution (DS) of CACS-FBP depended on the reaction temperature, reaction time, the mass ratio of fish bone collagen peptide to CACS (mFBP/mCACS) and the mass ratio of MTGase to CACS (mMTGase/mCACS). In addition, the antioxidant assay indicated that CACS-FBP had an excellent antioxidant capacity, and the CACS-FBP showed no cytotoxicity toward L929 mouse fibroblasts, all the results mean that the prepared peptide-containing chitosan derivative has potential application in pharmaceutical and biomedical fields.