Eugenol, the main bioactive compound in clove oil, suppressed intestinal inflammation and serum inflammatory cytokine levels by inhibiting NF-κB signaling through NF-κB phosphorylation, leading to the upregulation of tight junction proteins such as ZO-1, Occludin, and Claudin-1 in the jejunum of piglets infected with a transmissible gastro-intestinal enteritis virus [191], which in turn fortified the interaction among intestinal epithelial cells and stabilized their integrity, resulting in the formation of a solid physical barrier during infection [192]. This evidence concerns the gene NFKB1 and infection.