甘草提取物对四种牙周常见致病菌的抑菌作用

目的 体外评价甘草提取物对牙龈卟啉单胞菌、中间普氏菌、具核梭杆菌和伴放线放线杆菌四种牙周常见致病菌的抑制效果。方法 以牙龈卟啉单胞菌、中间普氏菌、具核梭杆菌和伴放线放线杆菌四种牙周常见致病菌作为供试菌，采用液体稀释法，考察甘草提取物对这四种细菌的最小抑菌浓度（MIC）和最小杀菌浓度（MBC）；并采用不同浓度的甘草提取物溶液，绘制甘草提取物对四种牙周致病菌的时间‒杀菌曲线。结果 甘草提取物对牙龈卟啉单胞菌、中间普氏菌、具核梭杆菌和伴放线放线杆菌的MIC值分别为1.50、1.50、0.75和1.50 mg/mL，MBC值分别为6、3、3和3 mg/mL。当甘草提取物达到对四种细菌的MBC值时，对于牙龈卟啉单胞菌、中间普氏菌、伴放线放线杆菌可在2 h后可达到杀菌效果，对于具核梭杆菌可在4 h后达到杀菌效果。结论 甘草提取物对以上四种牙周常见致病菌具有良好的抑菌及杀菌作用。

Antimicrobial activity of Glycyrrhiza uralensis extract against four common periodontal pathogens in vitro

Abstract: Objective To evaluate the antimicrobial activity of Glycyrrhiza uralensis extract against four common periodontal pathogens. Methods The minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) of Glycyrrhiza uralensis extract against Porphyromonas gingivalis (P. gingivalis), Fusobacterium nucleatum (F. nucleatum), Prevotella intermedia (P. intermedia) and Actinobacillus actinomycetemcomitans (A. actinomycetemcomitans) were determined by using microdilution technique. The time-kill curves against the four pathogens were dotted at different concentrations of the extract. Results The MIC values of Glycyrrhiza uralensis extract against P. gingivalis, P. intermedia, F. nucleatum and A. actinomycetemcomitans were 1.50, 1.50, 0.75 and 1.50 mg/mL respectively. The MBC values of Glycyrrhiza uralensis extract against P. gingivalis, P. intermedia, F. nucleatum and A. actinomycetemcomitans were 6, 3, 3 and 3 mg/mL respectively. After 2 hours of incubation, the Glycyrrhiza uralensis extrat killed 100% of P. gingivalis, P. intermedia and A. actinomycetemcomitans when its concentration reached the MBC values against the three bacteria respectively. The bactericidal effect of Glycyrrhiza uralensis (3 mg/mL) on F. nucleatum was achieved after 4 hours. Conclusion Glycyrrhiza uralensis extract has remarkably antibacterial and bactericidal effects against P. gingivalis, P. intermedia, F. nucleatum and A. actinomycetemcomitans.