目的 研究原白头翁素对铜绿假单胞菌（PA）的生长及群体感应系统（QS系统）调控的毒力因子表达的影响。方法 测定原白头翁素对PA的最低抑菌浓度和生长曲线，以40 μmol/L的呋喃酮C-30作为阳性对照，测定原白头翁素（40、80 μmol/L）对铜绿假单胞菌标准株PAO1生长曲线的影响以及QS系统调控的毒力因子中胞外3种毒力因子（绿脓菌素、蛋白水解酶和弹性蛋白酶）表达量的影响。结果 在实验所采用的浓度下，原白头翁素对铜绿假单胞菌的生长未表现出明显的抑制作用，但对PAO1的3种毒力因子均有抑制作用，并呈现出剂量相关性。结论 原白头翁素抗感染的机制可能是作用于铜绿假单胞菌的QS系统，抑制毒力因子表达，从而降低该菌的毒力。

Objective To study the effect of protoanemonin on the expression of virulence factors regulated by quorum sensing (QS) system of Pseudomonas aeruginosa (PA). Methods The minimum inhibitory concentration and growth curve of protoanemonin on PA were determined. With furanone C-30 (40 μmol/L) as positive control, the effect of protoanemonin (40 and 80 μmol/L) on the growth of PAO1 was assessed, and the effects on the expression levels of the extracellular virulence factors (pyocyanin, protease, and elastase) regulated by QS system were also evaluated. Results Protoanemonin in concentration used in this study had no significant effect on the growth of PAO1, but it had the inhibitory effect on the three virulence factors of PAO1 with a dosage-dependent manner. Conclusion It is possible that protoanemonin acts on QS system of PA to inhibit the expression of virulence factors, in order to reduce the virulence of the bacteria.