Study on the protective effects on H2O2-induced HEK-293 cells and Caco-2 cells and antioxidant stability of muscle enzymatic hydrolysate from Pacific saury (Cololabis saira)

This study investigated the protective effects of muscle enzymatic hydrolysates from Pacific saury ( Cololabis saira ) on H 2 O 2 -induced oxidative damage, as well as their antioxidant stability. The hydrolysate exhibited a high 1,1-Diphenyl-2-trinitrophenylhydrazine (DPPH) radical scavenging rate and significant reducing power. Meanwhile, it protected HEK-293 cells and Caco-2 cells against H 2 O 2 -induced oxidative damage by maintaining cell membrane integrity, inhibiting lipid peroxidation, and enhancing the levels of cellular antioxidant enzymes. Regarding antioxidant stability, the hydrolysate displayed favorable salt tolerance, retaining 80.33%±1.85% of its reducing power even at 10% NaCl concentration; high-temperature treatment (120°C), glucose addition and simulated gastrointestinal digestion observably enhanced its antioxidant activity, while alkaline environment, high NaCl concentration and ultraviolet irradiation significantly weakened the antioxidant activity. These results indicate that the hydrolysate from Pacific saury has good cell protection effects and is expected to be used in functional foods and nutritional supplements, but its antioxidant stability is easily affected by processing and storage conditions.