Exploring direct enzymatic hydrolysis of legumes: a promising approach for producing bioactive peptides

Bioactive peptides (BPs), short chains of amino acids with several health benefits, are derived from the enzymatic hydrolysis of food matrix proteins. Beginning with organic solvent protein extraction, studies of bioactive peptides published are primarily based on different complex steps. This study utilized direct enzymatic hydrolysis to obtain BPs from black beans, lentils, and peas. A Central Composite Rotational Design (CCRD) was employed to evaluate the effects of temperature (50 - 70 ºC), pH (7.5 - 8.5), and Alcalase® concentration (2 - 6% v/m) on the degree of hydrolysis (DH). The hydrolysates that showed the highest DH for each legume were scaled up 25-fold in a mini reactor and were subjected to ultra- and nanofiltrations for antioxidant activity evaluation using FRAP and DPPH procedures. Higher temperatures, Alcalase® concentrations, and alkaline pH levels increased DH for direct enzymatic hydrolysis of crude legume flours. Alcalase® concentration had the most significant impact. The highest antioxidant activity in the FRAP assay was observed at 5 kDa for peas. Beans exhibited a lower degree of hydrolysis (DH) compared to lentils and peas but demonstrated superior antioxidant activity in DPPH assays. The proposed method is advantageous for sustainable bioactive peptide production from legumes.