Antioxidant and Anti-Inflammatory Activities of Protein Hydrolysates from Mytilus Edulis and Ultrafiltration Membrane Fractions

Multifunctional bioactive peptides from Mytilus edulis were produced by gastrointestinal digestion. The optimal conditions for production were determined at an enzyme/substrate ratio of 1:500 for 30 min hydrolysis time based on antioxidant and anti-inflammatory assays. Thus, peptides at 1:500 were further fractionated based on molecular weight. The <1 kDa peptide fraction exhibited 0.25 μg/mL of IC50 value with the highest activity against 2,2-diphenyl-1-picrylhydrazyl scavenging activity, but similar reducing power and 2,2-azino-bis(3-ethylbenzthiazoline)-6-sulfonic acid (ABTS+) radical scavenging activity were observed in all fractions. In the oxygen radical absorbance capacity assay, the 1–5 kDa peptide fraction exhibited the best oxygen radical absorbance capacity value by 430.8 μM trolox equivalent/mg of sample. In addition, the 1–5 kDa peptide fraction exhibited 58.74% of protection ability against hydroxyl radical-induced DNA damage. In the NO inhibition assay, the >5 kDa peptide fraction showed 92.35% inhibition activity. All peptide fractions are rich in antioxidant amino acids such as Glu, Asp and His. Practical Applications Most studies suggest that the consumption of shellfish promotes health. Shellfish is rich in bioactive compounds such as protein, carbohydrate, lipids and minerals. In this study, we produced bioactive peptides from M. edulis by gastrointestinal digestion, and further fractionated using ultrafiltration membrane. The present results indicated that the M. edulis hydrolysates and its fractions exhibited the potent antioxidant and anti-inflammatory activities, and these activities would be useful to improve human health.