Antioxidant Properties of a Peptide-Enriched Fraction Derived from Salmon (Salmo salar) Bone Collagen

This study assessed the antioxidant
properties of peptide
mixtures
extracted from salmon bones using a basic saline solution extraction
process, either with ammonium hydrogen carbonate or a combination
of ammonium hydrogen carbonate and ammonium hydrogen phosphate. The
extracts were rich in collagen and derived peptides. After fractionating
based on molecular weight, the antioxidant activity of each fraction
was evaluated. ABTS (2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic
acid) assays revealed that the extracts obtained with ammonium hydrogen
carbonate solution and containing peptides below 10 kDa exhibited
the highest antioxidant activity. In vitro tests
confirmed that these extracts protected cells from oxidation induced
by hydrogen peroxide. High resolution respirometry, a method rarely
reported in other studies, demonstrated the extracts’ protective
effects at the mitochondrial level. Furthermore, a preservative effect
on the formation of new reactive oxygen species resulting from induced
oxidative stress was observed. Mass spectrometry revealed peptides
with known and predicted antioxidant motifs. This study highlights
the potential of fish bones, a major byproduct of the food industry,
as a valuable source of antioxidant compounds with applications in
cosmetics and biomedicine, beyond their traditional use for calcium
phosphate extraction.