Preparation and Characterisation of Collagen from Freshwater Fish Scales

Acid-soluble collagen (ASC) and pepsin-solubilized collagen (PSC) were prepared from the waste freshwater carp fish scales. The results of SDS-PAGE showed that purified collagens were composed of at least two different chains which were in accordance with the type I collagen with α chain composition of (α1)2α2. Compared with the carp fish ordinary muscle type I collagen , porcine dermis type I collagen and other seawater fish collagens, freshwater carp fish scales collagen contained relative high half-cystine (Cys-s), but lower denaturation temperature(Td) than the porcine dermis type I collagen. These collagens had evident absorption at 230 nm by UV-Vis spectra. The spectrum X-ray diffraction showed that the collagen remained single-helix and tri-helix configuration with the minimum values of the repeat spacings (d) of about 4.48 A and 11.87 A. Therefore, to make more effective use of limited-resources, carp fish scales can be a potential resource for the extraction of type I collagen or gelatin.