Anti-Inflammatory Effects of Sword Bean (Canavalia gladiata) and Its Lacticaseibacillus paracasei SKH 003-Fermented Extracts in LPS-Stimulated RAW 264.7 Macrophages

Chronic inflammation contributes to various metabolic and immune disorders. Plant-derived phytochemicals and fermented foods have attracted attention as dietary modulators of inflammation. This study evaluated the anti-inflammatory potential of sword bean (Canavalia gladiata) extract (CG) and its Lacticaseibacillus paracasei SKH 003-fermented derivative (CGF) in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. Cells were treated with CG or CGF (0–400 µg/mL) with or without LPS (0.1 µg/mL). Both CG and CGF significantly attenuated LPS-induced inflammatory responses while maintaining high cell viability. The extracts reduced nitric oxide (NO) and prostaglandin E2 (PGE2) production, suppressed mRNA expression of iNOS, COX-2, TNF-α, IL-6, IL-1β, MCP-1, and CXCL10, and upregulated IL-1Ra. Notably, CGF showed broader and stronger suppressive effects on most pro-inflammatory mediators, cytokines, and chemokines than unfermented CG, whereas IL-1Ra induction was comparable between the two extracts. Western blot analysis revealed that CGF inhibited the phosphorylation of NF-κB p65 and all three major MAPKs (p38, JNK, ERK), whereas CG showed limited effects on MAPK activation. These findings demonstrate that fermentation with the specific strain L. paracasei SKH 003 enhances the anti-inflammatory activity of sword bean extract by simultaneously targeting NF-κB and MAPK signaling pathways. Consequently, CGF holds significant potential as a functional food ingredient for managing macrophage-mediated inflammatory responses.