安息香提取物(XCQ)联合庆大霉素对铜绿假单胞菌的抗菌增效作用研究

Antibacterial synergism of benzoin extract(XCQ)combined with gentamicin against Pseudomonas aeruginosa

目的:考察安息香提取物XCQ联合庆大霉素体内、外抗铜绿假单胞菌的抗菌增效作用。方法:采用体外药物敏感性实验筛选铜绿假单胞菌临床株的多重耐药性菌株,并测定庆大霉素、左氧氟沙星和XCQ对铜绿假单胞菌临床株的最小抑菌浓度(minimum inhibitory concentration,MIC);采用牛津管法评价不同剂量XCQ联合庆大霉素的体外抗菌活性差异;通过小鼠尾静脉注射铜绿假单胞菌菌液构建小鼠细菌感染性疾病动物模型,造模前3h灌胃XCQ溶液和造模后立即灌胃给予庆大霉素溶液,统计5 d内感染小鼠的生存率。结果:筛选出一株铜绿假单胞菌多重耐药菌株,该菌株对庆大霉素的MIC值为1μg﹒mL-1;XCQ在体外能提高庆大霉素的抗菌活性,并存在量效关系;XCQ在体内能提高庆大霉素对感染小鼠的保护性,提高模型动物存活率。结论:安息香提取物XCQ在体内、外均能提高庆大霉素对抗铜绿假单胞菌的抗菌作用。

Objective:To investigate the antibacterial synergism of benzoin extract XCQ combined with gentamicin against Pseudomonas aeruginosa in vivo and in vitro.Method:In vitro drug sensitivity test was used to screen multi-drug resistant strains of clinical strains of Pseudomonas aeruginosa,and the minimum inhibitory concentration(MIC)of gentamicin,levofloxacin and XCQ against clinical strains of Pseudomonas aeruginosa was determined.The di■erence of in vitro antibacterial activity of di■erent doses of XCQ combined with gentamicin was evaluated by Oxford tube method.The animal model of bacterial infectious diseases in mice was constructed by injecting Pseudomonas aeruginosa bacterial solution through the tail vein of mice,and XCQ solution was intragastrically administered 3 hours before modeling and gentamicin solution was intragastrically administered immediately after modeling,and then the survival rate of infected mice within 5 days was counted.Result:A multi-drug resistant bacterium of Pseudomonas aeruginosa was selected,and the MIC of this strain to gentamicin was 1μg﹒mL-1.XCQ improved the antibacterial activity of gentamicin in vitro in a dose-response manner.XCQ could improve the protection of gentamicin to infected mice in vivo and improve the survival rate of model animals.Conclusion:Benzoin extract XCQ improves the antibacterial e■ect of gentamicin against Pseudomonas aeruginosa in vivo and in vitro.