Chromatographic separation and physicochemical properties of collagen species in the skin of deep-sea redfish (Sebastes mentella)

Type I collagen (PSC-I) and type V collagen (PSC-V) were directly separated by DEAE-cellulose chromatography without salt precipitation from the skin of deep-sea redfish after limited pepsin digestion. The yields of PSC-I and PSC-V were 79.4% and 8.4%, respectively. The denaturation temperature of PSC-V (17.8 °C) was significantly higher than that of PSC-I (15.9 °C), as a result of its higher total content of imino acid (17.1%) and hydroxylation degree of proline and lysine (44.7%) than those of PSC-I (14.7% and 35.8%). However, the intrinsic viscosity and viscosity transition temperature span of PSC-I (14.4 dL/g and 8 °C) were considerably higher than those of PSC-I (13.5 dL/g and 5 °C), which could be attributed to its greater extent of triple helix and more intermolecular crosslinks as shown by SDS-PAGE pattern and infrared spectra.