Abstract:Fish skin of Clarias fuscus was a by-product of freshwater aquatic products processing, which is rich in resources. To improve the utilization of aquatic by-products, the fish skin of Clarias fuscus was used as raw materials for acid-soluble collagen (ASC) extraction at 4 ℃. It’s the physicochemical of the extracts was then studied. The hydroxyproline experiment showed that the extraction yield of ASC reached 20.32%. The sample met the characteristics of type I collagen with the most abundant amino acid of glycine (32.59%) by analysis of amino acid compositions. SDS-PAGE and ultraviolet-visible (UV-Vis) spectra identified the sample was of a type I collagen protein with high purity. Fourier transform infrared (FT-IR) spectra of ASC suggested that the protein presented in the triple helix structure. The denature temperature (Td, 26 ℃) and shrinkage temperature (Ts, 53.01 ℃) showed that the thermal stability of the collagen was lower than collagen from mammalian. X-ray diffraction diagram showed the internal structure of the collagen molecules from Skin of Clarias fuscus.
