Bioactive and Functional properties of gelatin peptide fractions obtained from sea bass (Dicentrarchus labrax) skin

Fish skin is one of the most common resources of gelatin, which can be hydrolyzed bioactive peptides. In this study, gelatin from sea bass skin (SBS) was hydrolyzed with flavourzyme to obtain peptide fractions with different molecular weights and determined their bioactive and functional properties. All peptide fractions obtained showed antioxidant activity (DPPH and FRAP). The bass gelatin peptide fraction 1 (BF1) (≤5 kDa) showed the highest DPPH (44.9%) and FRAP (42.04 mmol Fe+2 /g and 22.98 mmol trolox/g) activities. Besides, the BF1 (≤5 kDa) peptide fraction showed the highest in vitro cytotoxic effect (16.58%) at 20 mg/mL concentration compared to the other peptide fractions. The highest emulsifying capacity (389.5 m2 /g), emulsifying stability (53.2 min), foaming capacity (30.47%), and foaming stability (10.40%) were obtained from the control gelatin sample. Moreover, the BF3 (≥10 kDa) peptide fraction showed an excellent fat binding capacity (9.39 mL/g). Enzymatic hydrolysis decreased emulsifying and foaming capacity of gelatin while increasing its fat binding capacity. In particular, antioxidant and anticancer activities of peptide fractions with low molecular weight were found to be high. The results demonstrated that gelatin and hydrolysates from the SBS offer an important alternative as a functional food ingredient for food technology