Impact of Telopeptides on Self-Assembly Properties of Snakehead (Channa argus) Skin Collagen

Much work has been done to understand the self-assembly properties of collagens from mammals. However, there is little information about fish-sourced collagens that are advantageous in certain applications. In this study, the self-assembly dynamics of tropocollagen (with telopeptides) and atelocollagen (without telopeptides) extracted from snakehead (Channa argus) skins was studied with turbidity, dynamic rheology, scanning electron microscopy (SEM), and quantitative percentage of self-assembly. Turbidity results indicate that the self-assembly of fish-sourced collagens followed the nucleation-growth two-step model, while rheological results unveiled two growth stages in the development of collagen gels. Based on SEM, telopeptides promoted the formation of thicker fibrils and increased the density of network that provided the structural basis of increased turbidity and strengthened storage and loss moduli. The SEM data were supported by the increased percentage of self-assembled collagens by telopeptides. Findings from this work may facilitate the understanding of structures and functions of products containing fish-sourced collagens and their application.