Dosler Sibel, Karaaslan Elif, Alev Gerceker A
a Faculty of Pharmacy, Department of Pharmaceutical Microbiology , University of Istanbul , Beyazit , Turkey.
b Faculty of Medicine, Department of Medical Microbiology , University of Bezmi Alem , Fatih , Istanbul , Turkey.
J Chemother. 2016 Apr;28(2):95-103. doi: 10.1179/1973947815Y.0000000004.
In vitro antibacterial and anti-biofilm activities of antimicrobial cationic peptides (AMPs) - melittin and colistin - both alone and in combination with antibiotics were evaluated against clinical isolates of Gram-negative bacteria. Minimum inhibitory concentration (MIC) and fractional inhibitory concentration (FIC) index were determined by the microbroth dilution and chequerboard techniques, respectively. The time-kill curve (TKC) method was used for determining the bactericidal activities of AMPs alone and in combination. Measurements of anti-biofilm activities were performed spectrophotometrically for both inhibition of attachment and 24-hour biofilm formation at MIC or subMIC. According to MIC90 values, the most active agents against Pseudomonas aeruginosa, Escherichia coli and Klebsiella pneumoniae were colistin, imipenem and ciprofloxacin, respectively. In combination studies, synergistic effects were mostly seen with colistin-imipenem against E. coli and K. pneumoniae (50 and 54%, respectively), colistin-ciprofloxacin against P. aeruginosa (77%). In TKC studies, synergism was observed with almost all expected combinations, even more frequently than chequerboard method. All of the antimicrobial agents were able to inhibit attachment and 24-hour biofilm formation between 0-57% at 1/10 × MIC and 7-73% at 1 × or 1/10 × MIC, respectively. AMPs seem to be a good candidate for antimicrobial chemotherapy with their antibacterial and anti-biofilm activities as a single agent or in combination with antibiotics.
评估了抗菌阳离子肽（AMPs）——蜂毒肽和多粘菌素——单独及与抗生素联合使用时对革兰氏阴性菌临床分离株的体外抗菌和抗生物膜活性。分别采用微量肉汤稀释法和棋盘法测定最低抑菌浓度（MIC）和分数抑菌浓度（FIC）指数。采用时间-杀菌曲线（TKC）法测定AMPs单独及联合使用时的杀菌活性。通过分光光度法测定MIC或亚MIC浓度下对细菌黏附的抑制作用以及24小时生物膜形成情况，以此评估抗生物膜活性。根据MIC90值，对铜绿假单胞菌、大肠杆菌和肺炎克雷伯菌最具活性的药物分别为多粘菌素、亚胺培南和环丙沙星。在联合研究中，多粘菌素-亚胺培南对大肠杆菌和肺炎克雷伯菌（分别为50%和54%）、多粘菌素-环丙沙星对铜绿假单胞菌（77%）大多表现出协同作用。在TKC研究中，几乎所有预期的联合用药都观察到了协同作用，甚至比棋盘法更频繁。所有抗菌药物在1/10×MIC时能分别抑制0 - 57%的细菌黏附和24小时生物膜形成，在1×或1/10×MIC时能抑制7 - 73%。AMPs作为单一药物或与抗生素联合使用时具有抗菌和抗生物膜活性，似乎是抗菌化疗的良好候选药物。
