抗菌肽与抗生素对革兰氏阴性菌和革兰氏阳性菌的体外协同抗菌效果研究

An in vitro Study on Combination of Antimicrobial Peptides and Antibiotics against Gram-negative and Gram-positive Bacteria

本试验旨在研究抗菌肽与抗生素联合使用对革兰氏阴性菌及革兰氏阳性菌的作用效果。通过最小抑菌浓度(mini muminhibitory concentration,MIC)测定,联合药敏试验,研究牛乳铁蛋白肽(Lactoferricin B,LFcin B)、天蚕素A(Cecropin A)及金霉素、新霉素对大肠杆菌(Escherichia coliATCC25922)、金黄色葡萄球菌(Staphylo-coccus aureus ATCC25923)、猪霍乱沙门氏菌(Sal monella choleraesuis CMCC50013)、铜绿假单胞菌(Pseudomonas aeruginosa CMCC10014)的体外协同抗菌效应。结果表明:Cecropin A与LFcin B联合使用对所试革兰氏阴性菌均表现为协同作用,两者联用时的MIC分别是单用时的1/4和1/8～1/4;金霉素与LFcin B联合使用对革兰氏阴性菌和阳性菌表现为协同作用,两者联用时的MIC是单用时的1/8～1/4;另外,Cecropin A与金霉素联合使用对革兰氏阴性菌也表现为协同作用。4种药物的两两合用对受试菌株均不表现拮抗作用。结果提示,LFcin B、Cecropin A及金霉素联合使用对革兰氏阴性菌及阳性菌具有协同作用。

This experiment was conducted to study the synergistic effects of antimicrobial peptides and antibiotics against Gram-negative and Gram-positive bacteria in vitro.A synergistic bactericidal effect was observed when combinations of LFcin B,Cecropin A,aureomycin and neomycin were used against Escherichia coli ATCC25922,Staphylococcus aureus ATCC25923,Salmonella choleraesuis CMCC50013,and Pseudomonas aeruginosa CMCC10014,using microbroth dilution method.The combination study showed synergy between LFcin B and Cecropin A,as well as LFcin B and aureomycin.In addition,Cecropin A was shown to be synergic with aureomycin.These results indicate that a synergistic effect exists when antimicrobial peptides and antibiotics were used in combination against Gram-negative and Gram-positive bacteria.