Systematic Purification of Peptides with In Vitro Antioxidant, Antihyperglycemic, Anti-Obesity, and Antidiabetic Potential Released from Sesame Byproduct Proteins

Sesame oil extraction byproduct (SOEB) contains a high percentage of protein (49.81 g/100 g), making it a suitable plant-based source for producing protein hydrolysates with nutraceutical potential. In this study, albumins, globulins, glutelins, and prolamins fractions were extracted and characterized from SOEB. These fractions were then enzymatically hydrolyzed with alcalase, yielding high soluble protein content (>90%) and hydrolysis degrees ranging from 34.66 to 45.10%. The hydrolysates were fractionated by molecular weight (<5 kDa, 3–5 kDa, 1–3 kDa, and <1 kDa). These fractions demonstrated potential for inhibiting the DPPH radical (25.19–95.79%) and the α-glucosidase enzyme (40.14–55.63%), particularly the fractions with molecular weight <1 kDa. We identified 28 peptides, with molecular weights between 332.20 and 1096.63 Da, which showed potent antioxidant activities (IC50 = 90.18 µg/mL), as well as inhibitory effects on key enzymes such as α-glucosidase (IC50 = 61.48 µg/mL), dipeptidyl peptidase IV (IC50 = 12.12 µg/mL), and pancreatic lipase (IC50 = 6.14 mg/mL). These results demonstrate the antioxidant, antihyperglycemic, antidiabetic, and anti-obesity potential of SOEB peptides, highlighting their use in the formulation of new functional foods or nutraceuticals.