Free radical scavenging and anti-inflammatory potential of a protein hydrolysate derived from salmon bones on RAW 264.7 macrophage cells.

ABSTRACT

BACKGROUND: Salmon bones, a waste by-product from the salmon industry, were used as a protein hydrolysate source for the production of bioactive peptides. The aim of this work was to evaluate the potential antioxidant and anti-inflammatory properties of salmon bone protein hydrolysate (SBPH). RESULTS: Salmon bones were hydrolyzed by separately using one of four proteases (Alcalase, Favourzyme, Neutrase and papain) at various concentrations (10, 25 and 50 mg mL-1 ), where the SBPH derived from 10 mg mL-1 papain hydrolysis exhibited the highest nitric oxide (NO) radical scavenging activity. After ultrafiltration, the MW < 0.65 kDa fraction showed the strongest NO inhibitory activity and was further fractionated by gel filtration chromatography (G1 and G2 fractions) and reverse-phase high-performance liquid chromatographic fractionation of the G1 fraction, from which the three main peaks (H1, H2 and H3) were found to have a marked NO-inhibitory activity and their peptide sequences were determined. Moreover, the G1 fraction was shown to inhibit both the lipopolysaccharide (LPS)-induced NO production and the LPS-induced inducible NO synthase , interleukin-6, tumor necrosis factor-α and induced NO production and the LPSCOX-2 mRNA levels in RAW 264.7 cells. CONCLUSIONS: Salmon bones from the salmon fisheries and farming industry were utilized by enzymatic hydrolysis for the production of valuable peptides. The results of this study suggested that bioactive peptides derived from salmon bones would be alternative anti-inflammation materials in functional resources. © 2019 Society of Chemical Industry.