Antioxidant activities of peptide hydrolysates obtained from the seeds of Treculia africana Decne (African breadfruit).

Protein hydrolysates usually possess higher nutritive value than an equivalent mixture of free amino acids. This study was aimed at determining the antioxidant activities of protein hydrolysates of Treculia africana seeds. Soluble protein was isolated from Treculia africana seed flour by alkaline solubilization and acid precipitation, and further hydrolyzed with three proteases (trypsin, pancreatin and pepsin) individually and in a sequential two- and three-protease systems. Antioxidant activities (DPPH, FRAP and lipid peroxidation) of the hydrolysates were investigated. Hydrolysates from Treculia africana seed protein showed varying degree of hydrolysis, pancreatin hydrolysates had the highest (94.92%) and pancreatin-pepsin hydrolysates had the least (6.59%). Pancreatin proved to be the most efficient protease for hydrolyzing Treculia africana protein with a high protein recovery of 156.06 mg/ml. Its hydrolysates exhibited the highest DPPH scavenging activity (71.02%) and had a high radical-mediated peroxidation of oleic acid. Likewise, pancreatin hydrolysates as well as trypsin-pancreatin hydrolysates showed the highest FRAP activity (37.17 and 38.52 µg/ml BHA, respectively). Pancreatin hydrolysates showed significant higher (p < 0.05) antioxidant potentials than other hydrolysates of T. africana seed protein. These findings showed the potential use of Treculia africana hydrolysates as antioxidants in reducing food spoilage and management of oxidative stress-related metabolic disorders.