牡荆素对铜绿假单胞菌生物膜形成的影响

Anti-biofilm effect of vitexin combined with antibiotics on Pseudomonas aeruginosa

目的探讨牡荆素与抗生素联用对铜绿假单胞菌生物膜的影响。方法通过微量肉汤稀释法检测铜绿假单胞菌对应各抗生素的最低抑菌浓度;利用96孔细胞培养板结合结晶紫染色法探讨牡荆素单独使用及与抗生素联用对铜绿假单胞菌生物膜的影响。结果当牡荆素的浓度≥31.25μg/ml时,能抑制PAO1生物膜的形成,使生物膜的总量从100%减少到(80.00±4.62)%,且随着牡荆素的浓度增高,其抑制能力越强;4种抗生素头孢他啶(CAZ)、环丙沙星(CIP)、庆大霉素(GEN)和左旋氧氟沙星(OFLX)的最低抑菌浓度(MIC)分别为0.5、0.5、2.0和8.0μg/ml;亚抑菌浓度的CAZ、CIP、GEN和OFLX与牡荆素联用时能协同抑制PAO1生物膜的形成,分别使生物膜的总量从100%下降至(39.38±5.32)%、(40.31±2.95)%、(23.31±3.95)%和(50.23±3.14)%。结论牡荆素能抑制铜绿假单胞菌生物膜的形成,且与抗生素联用时有协同作用。

Objective To explore the anti-biofilm effect of vitexin combined with antibiotics on Pseudomonas aeruginosa. Methods Minimal inhibitory concentrations（MICs） of antibiotics to P. aeruginosa were determined by broth microdilution method. And 96-well cell culture plate combined with crystal violet was used to study antibiofilm effect of vitexin alone or combined with antibiotics. Results Vitexin could significantly inhibit P. aeruginosa biofilm formation from 100.00% to（80.00 ± 4.62） % at the concentration ≥ 31.25 μg/ml in a dose-dependent manner（P〈0.05）. The MICs of CAZ, CIP, GEN and OFLX were 0.5, 0.5, 2.0 and 8.0 μg/ml, respectively. And vitexin showed synergistic inhibition of PAO1 biofilm formation when combined with sub-MIC of CAZ, CIP, GEN and OFLX, which could reduce the total amount of biofilm from 100.00% to（39.38 ± 5.32） %,（40.31 ± 2.95） %,（23.31 ± 3.95） % and（50.23 ± 3.14） %, respectively（P〈0.05）. Conclusions Vitexin significantly inhibitsbiofilm formation of P. aeruginosa, and shows synergistic effect when combined with antibiotics.