Antibacterial Activities of Grape Seed Procyanidins Against Streptococcus Mutans in Vitro

OBJECTIVE To study the antibacterial activity of grape seed procyanidins (GSPC) against streptococcus mutans in vitro and to explore its anti-caries potential. METHODS Broth micro-dilution method was used to determine minimal inhibitory concentration (MIC)， minimal bactericidal concentration (MBC) and minimal biofilm inhibitory concentration (MBIC); crystal violet semi-quantitative method was used to determine biofilm-formation; anthrone sulfuric acid method was used to test glucan production and pH was used to test acid generation. RESULTS MIC value of GSPC was 12.5 mg/mL while MBC value and MBIC value were both 50 mg/mL. GSPC (≥12.5 mg/mL) could reduce biofilm formation， and especially when its content increased to eight times of MIC content(100 mg/mL)， the inhibition rate was able to achieve 76%. Also it had the ability of inhibiting the glucan production and acid generation at lower content than that of MIC. CONCLUSION GSPC shows antibacterial activity and inhibitory effects on biofilm-formation and cariogenic virulence factors against streptococcus mutans in vitro.