Discovery and functional validation of a novel lotus root-derived peptide (EWGHLGL) alleviating oxidative stress in vitro and in vivo

Lotus root ( Nelumbo nucifera ) is a nutrient-rich source of bioactive peptides. This study extracted lotus root juice and identified a novel antioxidant peptide, EWGHLGL, using LC–MS/MS and computational methods including molecular docking and molecular dynamics simulations. Molecular docking revealed its strong binding affinity to myeloperoxidase (MPO; −9.345 kcal/mol), while molecular dynamics simulations confirmed stable RMSD fluctuations (<0.4 nm). EWGHLGL exhibited concentration-dependent scavenging of DPPH and ABTS radicals (up to 50.14 % and 47.45 %, respectively). In vitro, EWGHLGL improved the viability of H 2 O 2 -induced HaCaT cells and reduced intracellular reactive oxygen species (ROS). In vivo, it enhanced superoxide dismutase (SOD) and catalase (CAT) activity while decreasing malondialdehyde (MDA) levels in mouse liver tissues, confirming antioxidant efficacy. These findings suggest EWGHLGL may serve as a natural antioxidant additive in functional foods or therapeutic agents, and this work offers a strategy for screening food-derived antioxidants, promoting the high-value utilization of lotus root. • Comprehensive peptide data ‌: Detailed information for all 1548 pre-screened peptides (RT, MS/MS, sequences, etc.) is now provided in the supplementary file “Peptide Identification Information (<1000 Da).xlsx”. • Dose rationale ‌: The 50 mg/kg animal dose used synthetic EWGHLGL to standardize mechanistic studies; future work will quantify natural peptide levels in lotus root. • MS/MS robustness ‌: Acknowledged signal-to-noise limitations in Fig. 2; future studies will optimize detection protocols for higher confidence.