Comprehensive analysis of fish collagen from Black Sea salmon (<i>Salmo labrax</i>) and Atlantic salmon (<i>Salmo salar</i>): isolation and comparative characterization for biomedical applications

Fish collagen, a vital structural protein abundant in different parts of fish, for example bone, skin and scales, has garnered substantial attention in recent years for its remarkable properties and diverse applications. With the scope of that, the macromolecular properties of Atlantic salmon (Salmo salar) and Black Sea salmon (Salmo labrax) collagens from bone and skin were analyzed using various methods such as Fourier transform infrared and Raman spectroscopies, differential scanning calorimetry (DSC), zeta potential measurements and high-performance liquid chromatography. It was found that collagen from Salmo salar fishbone (SSF) contained the highest concentration of imino acids (484/1000), followed by Salmo salar bone (SSB) (453/1000). The thermal denaturation (Td) of fish collagen was determined between 34.24 and 37.84 degrees C depending on organs (fishbone, skin and bone), which is higher than the denaturation temperature of collagens from many types of marine organisms. DSC data were confirmed by particle size analysis. Collagens isolated from fish were made into films and biocompatibility studies were carried out with human umbilical vein endothelial cells. Resazurin-based cell proliferation test and morphological examination of the cells under a fluorescence microscope showed that SSB collagen gave the best results. The present study strongly suggests that fish collagens can be used for biomedical applications. (c) 2025 Society of Chemical Industry.