Unveiling the patterns and mechanisms of time-specific release of multifunctional peptides from cricket protein

Endpoint-based studies failed to clarify time-resolved hydrolysis properties, bioactivities, peptide profiles, and structural characteristics. Current study aimed to explore the correlations of these characteristics during Alcalase hydrolysis of cricket protein (CP) for 30-300 min. Prolonged hydrolysis increased degree of hydrolysis (DH) to 20.3%, with low-molecular-weight peptides (< 2 kDa) accounting for 88.0%-94.0%. Cricket protein hydrolysates (CPHs) showed strongest antioxidant and angiotensin I-converting enzyme (ACE) inhibitory activities at 30 and 300 min, respectively, whereas dipeptidyl peptidase-IV (DPP-IV) inhibition exhibited a bimodal pattern. Structural analyses demonstrated hydrolysis disrupted ordered CP structure, with α-helix+β-sheet decreasing by 17.4%-26.5%, alongside lowered surface hydrophobicity and increased sulfhydryl exposure. Antioxidant and ACE inhibition were positively associated with structural unfolding and hydrolysis property promotion, whereas DPP-IV inhibition appeared to relate more to peptide-release characteristics. Activity-guided peptidomics and multivariate analyses prioritized LYPL/VYGPL, SGLFDK/PAALGL, and SGPRLH/FAGPS as candidate peptides potentially associated with antioxidant, ACE inhibitory, and DPP-IV inhibitory activities, respectively.