Antimicrobial and Anti-Inflammatory Effects of the Ethanol Extract of Polygonum cuspidatum as a Mouthwash Component

Abstract

Polygonum cuspidatum (PC) has been used as traditional Korean medicine to treat various diseases including asthma, hypertension, cancer, and arteriosclerosis. In this study, we assessed the antibacterial and anti-inflammatory effects of PC ethanol extract. Persistent antibacterial activity against Streptococcus mutans for up to 23 days was observed when the extract was used at a concentration of 10 mg/mL. The minimum inhibitory concentration of PC against S. mutans was 0.2 mg/mL and the minimum bactericidal concentration was 10 mg/mL. We compared the antimicrobial activities of S. mutagens cultured with or without PC. Bacterial activity was observed only in the group where RE was not added. The anti-inflammatory effect of PC on RAW264.7 cells was assessed using the MTT assay; changes in nitric oxide (NO) production and inflammatory cytokine levels (tumor necrosis factor [TNF]-α and interleukin [IL]-6) were measured in the presence of PC. In lipopolysaccharide-induced RAW264.7 cells, PC inhibited NO production by 68.6% when used at a concentration of 50 µg/mL. The expression of TNF-α and IL-6 was reduced by PC in a concentration-dependent manner. These results suggest that the ethanol extract of PC could be used as a mouthwash component with antibacterial and anti-inflammatory effects.