硝酸镓联合氧氟沙星抑制尿路致病性大肠杆菌生物膜形成

Inhibition of Uropathogenic Escherichia Coli Biofilm by the Combination of Gallium Nitrate and Ofloxacin

目的观察硝酸镓联合氧氟沙星对尿路致病性大肠杆菌（uropathogenic Escherichia coli,UPEC）生物膜形成的抑制作用。方法采用结晶紫染色法检测5株UPEC生物膜形成过程,将0.5×最低抑菌浓度（MIC）的硝酸镓和氧氟沙星单独应用与联合使用,计算其对UPEC生物膜的抑制率。结果 2种药物单独应用只能部分抑制生物膜形成,0.5×MIC硝酸镓（4.00μg·m L^-1）和0.5×MIC氧氟沙星（0.25μg·m L^-1）联合应用对细菌生物膜的抑制率为94.46%-97.03%,明显强于2种药物单独作用（P〈0.01）。结论硝酸镓联合氧氟沙星对UPEC生物膜形成有明显抑制作用,对尿路感染的防治具有进一步应用价值。

OBJECTIVE To study the inhibitory effects of combination of gallium nitrate and ofloxacin on the biofilm formation produced by five strains of uropathogenic Escherichia coli（UPEC）. METHODS The crystal violet staining was used to measure the development of UPEC biofilm. The effects of gallium nitrate and ofloxacin on biofilm were evaluated separately or synergeticly at 0.5×minimal inhibitory concentration（MIC）. RESULTS Single use of gallium nitrate or ofloxacin partly inhibited biofilm growth, while 4.00 μg·m L^-1 of gallium nitrate combined with 0.25 μg·m L^-1 of ofloxacin inhibited UPEC biofilm formation by 94.46%-97.03%, which were better than separate use of gallium nitrate or ofloxacin（P〈0.01）. CONCLUSION The combination of gallium nitrate and ofloxacin have obvious inhibitory effects on UPEC biofilm formation, showing the potential application value for prevention and control of urinary tract infection.