# Antioxidant Activity In Vitro and Protective Effects Against Lipopolysaccharide-Induced Oxidative Stress and Inflammation in RAW264.7 Cells of Ulva prolifera-Derived Bioactive Peptides Identified by Virtual Screening, Molecular Docking, and Dynamics Simulations

## TL;DR

This paper identifies a potent antioxidant peptide from Ulva prolifera algae that can reduce oxidative stress and inflammation in lab-grown macrophages.

## Contribution

A novel antioxidant peptide, DWS, was identified through computational and experimental methods for its protective effects against inflammation.

## Key findings

- DWS peptide showed strong antioxidant activity in vitro via DPPH and ABTS assays.
- Molecular docking and simulations showed DWS forms stable complexes with Keap1 protein.
- DWS alleviated LPS-induced oxidative stress and inflammation in RAW264.7 cells.

## Abstract

Large-scale blooms of Ulva prolifera severely impact coastal ecosystems and economic development. In addressing Ulva management, the development of high-value utilization approaches for this macroalga remains crucial. Compared to other marine algae, Ulva prolifera exhibits higher protein content with diverse amino acid profiles, and existing studies demonstrate that hydrolyzed Ulva prolifera proteins can yield biologically active peptides with functional potential. Conventional methods for producing bioactive peptides are often cost-intensive. Here, we employed in silico enzymatic hydrolysis to generate small peptides from Ulva prolifera protein. Through computer screening, molecular docking with the Keap1 protein, and molecular dynamics simulations, we identified a potential antioxidant peptide, DWS (Asp-Trp-Ser). Molecular docking and dynamics simulations revealed that DWS forms stable complexes with Keap1 by establishing hydrogen bonds and Pi bonds with conserved amino acid residues (Leu557, Gly558, Ile559, Val604, Val606, and Arg415). In vitro antioxidant assays demonstrated that DWS exhibits potent DPPH and ABTS radical scavenging activities as well as reducing power. Cellular experiments showed that DWS effectively alleviates LPS-induced oxidative stress and inflammation in RAW264.7 macrophages.