Optimizing mung bean and soybean hydrolysis for the generation of bioactive peptides of potential functional food applications

This study investigates the enzymatic hydrolysis of soybean (<i>Glycine max</i> L.) and mung bean (<i>Vigna radiata</i>) proteins using bromelain, ficin, papain, and pepsin to improve digestibility and functional properties. We hypothesized that mung bean's less compact structure would yield higher degree of hydrolysis (DH) and bioactive peptides compared to soybean, enhancing antioxidant capacity for functional foods. Mung bean showed significantly higher proteolysis, with a maximum DH of 46.5 ± 2.1 % (<i>p</i> ≤ 0.05) using 10 % bromelain for 12 h, versus soybean's 26.9 ± 1.5 % (p ≤ 0.05). Bromelain and ficin outperformed papain and pepsin, producing up to 62.3 ± 3.2 % oligopeptides and 32.4 g/100 g free amino acids in mung bean. Mung bean hydrolysates exhibited superior antioxidant activity, reaching 78.4 ± 2.5 % DPPH scavenging (p ≤ 0.05), compared to soybean's 58.9 ± 2.0 % (p ≤ 0.05), due to increased 200-1000 Da peptides. Optimal conditions (10 % enzyme, 12 h) improved solubility and bioactivity, highlighting mung bean's potential and bromelain's efficacy for sustainable food applications, warranting further protease research.