Antioxidant\nProperties of a Peptide-Enriched Fraction\nDerived from Salmon (Salmo salar) Bone\nCollagen

This study assessed the antioxidant\nproperties of peptide\nmixtures\nextracted from salmon bones using a basic saline solution extraction\nprocess, either with ammonium hydrogen carbonate or a combination\nof ammonium hydrogen carbonate and ammonium hydrogen phosphate. The\nextracts were rich in collagen and derived peptides. After fractionating\nbased on molecular weight, the antioxidant activity of each fraction\nwas evaluated. ABTS (2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic\nacid) assays revealed that the extracts obtained with ammonium hydrogen\ncarbonate solution and containing peptides below 10 kDa exhibited\nthe highest antioxidant activity. <i>In vitro</i> tests\nconfirmed that these extracts protected cells from oxidation induced\nby hydrogen peroxide. High resolution respirometry, a method rarely\nreported in other studies, demonstrated the extracts’ protective\neffects at the mitochondrial level. Furthermore, a preservative effect\non the formation of new reactive oxygen species resulting from induced\noxidative stress was observed. Mass spectrometry revealed peptides\nwith known and predicted antioxidant motifs. This study highlights\nthe potential of fish bones, a major byproduct of the food industry,\nas a valuable source of antioxidant compounds with applications in\ncosmetics and biomedicine, beyond their traditional use for calcium\nphosphate extraction.