亚抑菌浓度头孢他啶对铜绿假单胞菌生物膜的影响

Effect of subminimal inhibitory concentration of ceftazidime on Pseudomonas aeruginosa biofilm in vitro

目的探讨亚抑菌浓度头孢他啶对铜绿假单胞菌生物膜的抑制和分散作用。方法用96孔板结合结晶紫染色法检测铜绿假单胞菌生物膜的形成和分散;用化学比色法测定铜绿假单胞菌毒力因子青脓素分泌能力;用比浊法检测头孢他啶对铜绿假单胞菌浮游菌生长的影响。结果 0.031 3μg/m L头孢他啶能显著抑制铜绿假单胞菌标准菌株PAO1生物膜的形成(t=156.70,P<0.05)及毒力因子青脓素产生(t=3.86,P<0.05),而不影响浮游菌的生长。当头孢他啶浓度为0.031 3μg/m L时能分散24 h成熟生物膜(t=4.32,P<0.05),且呈一定的时间-剂量依赖性。0.031 3μg/m L头孢他啶能显著抑制铜绿假单胞菌起始黏附能力(t=5.54,P<0.05);亚抑菌浓度头孢他啶显著抑制临床分离铜绿假单胞菌菌株生物膜的形成,但各菌株对亚抑菌浓度头孢他啶的生物膜形成敏感性各异。结论亚抑菌浓度头孢他啶能有效抑制和分散铜绿假单胞菌生物膜,在相关生物膜感染疾病治疗中具有潜在价值。

Objective To investigate the inhibition and dispersion effects of subminimal inhibitory concentration （sub-MIC） of ceftazidime （CAZ） on the biofilm formation of Pseudomonas aeruginosa （P. aeruginosa）. Methods The biofilm formation and dispersion of P. aeruginosa were detected by 96-well cell culture plate combined with crystal violet staining. The pyocyanin level secreted by P. aeruginosa was determined with a chemical colorimetric method, and the effect of sub-MIC of CAZ on the growth of P. aeruginosa was detected by a turbidity method. Results Sub-MIC （0.031 3 μg,/mL） of CAZ significantly inhibited the biofilm formation （t = 156.70, P 〈 0.05 ） and pyocyanin production （ t = 3.86, P 〈 0.05 ） of P. aeruginosa （ standard strain PAO1 ） but had no influence on its growth. When the concentration of CAZ was equal to or above 0.031 3 μg/mL, the 24-hour mature biofilm was significantly dispersed by CAZ in a dose-dependent manner （t = 4.32,P 〈 0.05）. In addition, 0.031 3 p^g/mL of CAZ significantly inhibited the initial adherence of P. aeruginosa （ t = 5.54, P 〈 0. 05 ）. Moreover, sub-MIC of CAZ significantly inhibited the biofilm formation of clinical isolates of P. aeruginosa with different sensitivity for different isolates. Conclusion Sub-MIC of CAZ can effectively inhibit and disperse the biofilm of P. aeruginosa, and may be used to treat the infection diseases related to biofilm formation.