Effect of thermal denaturation on the properties of collagen sponges from fish

In this paper,native collagen(NC)was extracted from skin of grass carp,and it was proved typeⅠ collagen with intact triple helix structure via the DSC and circular dichroism and SDS-PAGE analysis.Low thermal denaturation(LD),high thermal denaturation(HD)and complete thermal denaturation(CD)collagen samples were obtained by heat treatment of NC under different conditions,and the degrees of thermal denaturation of them were 16.9%,57.9and 100%respectively,according to the changes of thermal denaturation enthalpy from DSC determination.On this basis,the research focused on the influences of heat treatment on the collagen structure and the corresponding properties of collagen sponges.The results show that the onset endothermic temperature(To)is the threshold temperature for the molecule structure and sponges properties stability.When subjected to temperatures above this threshold temperature even in a short time,the triple helix structure of collagen would completely or partially unfold.At the same time,the ordering of material structure,mechanical properties and enzymatic sensitivities of collagen sponges reduced,the cell proliferation ability enhanced along with the rise of degrees of thermal denaturation of collagen.The findings demonstrate Tois the crucial temperature and this temperature should not be exceeded during the production and utilization of native collagens.