Comprehensive characterization of bioactive peptides in rice bran protein hydrolysates: A multi-platform approach for metabolomic profiling, identification, and molecular docking analysis

Background and Objectives

To optimize the utilization of rice by-products, the rice bran protein hydrolysate (RBPH) was subjected to a process of separation and purification using ultrafiltration and reversed-phase high-performance liquid chromatography (RP-HPLC). Subsequently, the identification of peptide sequences was carried out using mass spectrometer hybrid quadrupole-time-of-flight and nontargeted metabolomic profiling done using UHPLC-QTOF-IMS profiling to identify antioxidant and antihypertensive amino acids.

Findings

Three novel bioactive peptides, namely, STCCK, FMKSK, and KICILVFTLTTC, were identified within RBPH through enzymatic digestion using alcalase, pepsin, and trypsin. These peptides showed significant antioxidant activity and angiotensin-converting enzyme (ACE) inhibitory activity. Molecular docking analyses elucidated various interaction mechanisms between these peptides and the ACE receptor protein, including hydrogen bonding and hydrophobic interactions. This suggested that the peptides effectively suppress ACE by forming hydrogen bonds with the active pockets of human ACE with a high affinity.

Conclusion

In summary, peptides derived from rice bran protein exhibited distinguished antihypertensive and antioxidant properties, underscoring their potential for valuable utilization in addressing utilization of rice by-products.

Significance and Novelty

The study advances scientific knowledge and offers practical solutions for health improvement and sustainable agriculture.