芪归银方联合左氧氟沙星对铜绿假单胞菌体外抑菌及血清药理学试验

In vitro bacteriostatic and serum pharmacological tests of Qiguiyin decoction combined with levofloxacin against pseudomonas aeruginosa

目的基于中药提取物和含药血清两个层次研究芪归银方(Qiguiyin decoction,QGYD)对铜绿假单胞菌(seudomonas aeruginosa,PA)标准菌株和耐药菌株的抑制作用及OGYD增强左氧氟沙星(levofloxacin,LEV)抗菌活性的作用,为中药联合抗生素防治耐药菌的临床用药提供参考。方法采用肉汤稀释法测定LEV、QGYD对PA的最低抑菌浓度(minimum inhibitory concentration,MIC)和最小杀菌浓度(minimum bactericidal concentration,MBC);微量棋盘稀释法测定两药联合的MIC,计算抑菌浓度指数(fractional inhibitory concentration index,FICI);制备LEV组、QGYD组、LEV+QGYD组和空白对照组血清,用MHB肉汤将各组血清均稀释成10%~90%12种浓度干预PA,测定血清的抑菌率、MIC_(90)和MBC。结果LEV联用QGYD后药液对PA(标准/耐药)的MIC明显降低,0.5<FICI≤1;各组10%~90%含药血清对PA(标准/耐药)具有一定程度的抑制作用,且呈现随着血清比例的增加抑菌率逐渐升高的趋势;与空白对照组血清相比,QGYD组含药血清的抑菌作用明显增强;LEV组血清对PA标准菌株MIC_(90)为15%,联合QGYD后MIC_(90)下降到10%,MBC均为15%。对PA耐药菌株的MIC_(90)为55%,联合QGYD后MIC_(90)为45%,降低了10%。结论QGYD提取物和QGYD含药血清均能有效抑制PA;LEV联合QGYD后药液和含药血清对PA的MIC或MIC_(90)均明显降低,抗菌活性增强。

Aim To investigate the antibacterial activity and anti-resistant mutation ability of Qiguiyin decoction(a traditional Chinese herbal formula)combined with levofloxacin against pseudomonas aeruginosa by antibacterial experiment in vitro and serum pharmacology.Methods The minimal inhibitory concentrations(MICs)of levofloxacin and Qiguiyin decoction were detected respectively by the broth dilution technique.The MIC of the combination of two drugs was determined by the micro chessboard dilution method.The effects of combined drugs on enhancing the antibacterial activity of different strains were evaluated respectively by calculating the fractional inhibitory concentration index(FICI).The drug-containing serum of levofloxacin group,Qiguiyin decoction group,Qiguiyin decoction combined with levofloxacin group and control group was prepared.The antibacterial rate,MIC and MBC of 10%~90% serum against the two strains were determined.Results Combined with Qiguiyin decoction,MIC of levofloxacin against pseudomonas aeruginosa(standard/resistant)decreased significantly,0.5<FICI≤1.With the increase of the proportion of serum,the inhibitory rate of 10%~90% drug-containing serum to pseudomonas aeruginosa(standard/resistant)increased gradually.Compared with the control group,the inhibitory effect of the Qiguiyin group on bacteria was significantly enhanced.The MIC_(90) of levofloxacin containing serum to pseudomonas aeruginosa standard strain was 15%.After combined with Qiguiyin decoction,MIC_(90) decreased to 10%,and MBC was 15%;MIC_(90) of the levofloxacin group was 55%,and that of the levofloxacin combined with Qiguiyin decoction group was 45%,which decreased by 10%.Conclusions Both Qiguiyin decoction and Qiguiyin serum can effectively inhibit pseudomonas.MIC of liquid and MIC_(90) of drug-containing serum to pseudomonas decrease significantly and the antibacterial activity increases after the combination of levofloxacin with Qiguiyin.