Preparation, antioxidant activity evaluation, and identification of antioxidant peptide from black soldier fly (Hermetia illucens L.) larvae

Black soldier fly larvae protein (BLP) was hydrolyzed using alcalase, neutrase, trypsin, and papain. The BLP hydrolysates (BLPHs) were fractionated by ultrafiltration into three peptide fractions of molecular weight (<3 kDa, 3-10 kDa and >10 kDa). Their antioxidant activities in vitro and the amino acid composition were determined. Results showed that the alcalase was more efficient in hydrolyzing the BLP into oligopeptides. BLPHs-I presented the best scavenging activity to superoxide radicals, hydroxyl radicals, DPPH, and ABTS radicals. The best scavenging activities were found in BLPHs-I containing high levels of aromatic and hydrophobic amino acids. Seventeen novel sequences with typical features of well-known antioxidant proteins were identified by LC-MS/MS. Results demonstrated that BLPHs-I possesses a great capacity as antioxidant peptides applied in functional foods. Practical applications Black soldier fly larvae protein (BLP) can also be hydrolyzed to produce antioxidant peptides and their sequences were identified. It can be used in pharmaceutical products and functional foods.