Fish sarcoplasmic proteins as a high value marine material for wound dressing applications

Fish sarcoplasmic proteins (FSP) constitute around 25–30% of the total fish muscle protein. As the FSP are water soluble, FSP were isolated from fresh cod (Gadus morhua) by centrifugation. By SDS-PAGE was possibly determined the composition of FSP extracts (FSP-E). The FSP-E denature at 44.12 ± 2.34˚C, as characterized by differential scanning calorimetry thermograms (DSC). The secondary structure of FSP-E is mainly composed by α-helix structure, as determined by circular dichroism. The cytocompatibility of FSP-E, at concentrations ranging from 5 to 20 mg/mL, was also investigated. For concentrations lower than 10 mg/mL, no cytotoxicity was observed over 72h of fibroblasts culture. Further on, FSP membranes (FSP-M) were produced by spin coating technique to evaluate its properties. FSP-M had uniform surface as analyzed by SEM, and the amount of α-helix structure increased when compared with the FSP-E. The FSP-M are more stable than the FSP-E, since they presented a denaturation temperature of 58.88 ± 3.36˚C, according to the DSC thermogram. FSP-M shown distinctive mechanical properties, with a stiffness of 16.57 ± 3.95 MPa and a yield strength of 23.85 ± 5.97 MPa. Human lung fibroblasts (MRC-5 cell line) cultured in direct contact with FSP-M demonstrate to be cytocompatible for 48h. Based on these results, FSP can be considered a potential biomaterial, recovered from the nature, for wound dressing applications.