Evaluation of Antioxidant, Antihypercholesterolemic and Cytotoxic Activity of Peptide Fractions from Melon (Cucumis melo) Seed

Bioactive peptides are becoming more widely acknowledged as multifunctional substances that promote human health. Several reports revealed their therapeutic effects including antioxidant, anticancer, antihypertensive, cholesterol-lowering effects, etc. The present study aims to investigate the antioxidant, antihypercholesterolemic, and cytotoxic activities of peptides extracted from melon seed. The melon seeds were removed from fruits collected from a local market, dried and ground into powder. Protein hydrolysis was conducted by pepsin, thermolysin and trypsin digestion. Fractionation of the hydrolysate to obtain the peptide fractions (< 10 kDa, 10–30 kDa and > 30 kDa) was performed using ultrafiltration membranes. The fraction exhibiting the strongest antioxidant activity underwent further assays for anti-hypercholesterolemic and cytotoxic effects. It was observed that the fraction containing peptides of < 10 kDa molecular weight exhibited greatest antioxidant activity. Additionally, < 10 kDa fraction also showed antihypercholesterolemic and cytotoxic properties. Overall, this study suggests that peptides extracted from melon seed, particularly those with a molecular weight of < 10 kDa exhibit multifunctional activities, including antioxidant, antihypercholesterolemic, and cytotoxic properties, potentially conferring health benefits for humans.