ε-多聚赖氨酸与乳链菌肽对抑制金黄色葡萄球菌生物膜生长的研究

Study on the anti-biofilm growth of Staphylococcus aureus by epsilon polylysine and nisin

目的:金黄色葡萄球菌是医院感染中检出率较高的致病菌,运用ε-多聚赖氨酸与乳链菌肽对金黄色葡萄球菌及其生物膜的抗性进行研究,试图找出一种新型的抗致病菌的抗菌物质。方法:采用微量肉汤稀释法测定不同浓度的ε-多聚赖氨酸和乳链菌肽对金黄色葡萄球菌最低抑菌浓度(MIC);通过结晶紫染色,运用光密度法,探讨ε-多聚赖氨酸和乳链菌肽单独及联合使用对金黄色葡萄球菌生物膜作用的规律。结果:乳链菌肽对金黄色葡萄球菌的MIC为3.76μmol/L,ε-多聚赖氨酸MIC值为10.99μmol/L,乳链菌肽与ε-多聚赖氨酸的比例分别为91、82、73、64、55、46、37、28、19时,MIC值分别为3.20μmol/L、2.79μmol/L、4.94μmol/L、4.44μmol/L、4.02μmol/L、3.68μmol/L、6.79μmol/L、6.29μmol/L、11.73μmol/L。ε-多聚赖氨酸与乳链菌肽对金黄色葡萄球菌生物膜的形成具有抑制作用,且呈浓度相关性,抑制效果随浓度增高而增强。结论:乳链菌和ε-多聚赖氨酸单独使用时,ε-多聚赖氨酸对金黄色葡萄球菌抑菌效果较差,乳链菌抑菌效果较好;若两者联合使用时乳链菌肽和ε-多聚赖氨酸浓度比选择为64、55、46对金黄色葡萄球菌生物膜生长抑制效果较好。

Objective：Staphylococcus aureus is a pathogen of high detection rate of hospital infection.Anti-biofilm of Staphylococcus aureus was detected by epsilon Polylysine and nisin on,in order to attempt to find a new type of antibacterial material of pathogenic bacteria.Method：Minimum inhibitory concentration（MIC）of epsilon polylysine and nisin against Staphylococcus aureus of were determined by broth micro-dilution method using different concentration;Mechanism on epsilon polylysine and nisin alone and in combination with the use against Staphylococcus aureus biofilm was performed by crystal violet staining using the optical density method.The results showed that the effect of epsilon polylysine and nisin on the formation of Staphylococcus aureus biofilm was inhibited,and the inhibition effect was increased with increasing concentration.Result：The MIC of nisin against Staphylococcus aureus was 3.76μmol/L,and the MIC value of epsilon polylysine was 10.99μmol/L,Nisin and epsilon polylysine proportion of mole were 91,82,73,64,55,46,37,28 and 19 respectively,MIC values were 3.20μmol/L,2.79μmol/L,4.94μmol/L,4.44μmol/L,4.02μmol/L,3.68μmol/L,6.79μmol/L,6.29μmol/L and 11.73μmol/L separately.The results showed that the effect of epsilon polylysine and nisin against the formation of Staphylococcus aureus biofilm was inhibited,and the inhibition effect was increased with increasing concentration.Conclusion：Epsilon polylysine alone has poor bacteriostatic effect against Staphylococcus aureus,but nisin has better antibacterial effect;If both were used together,nisin and epsilon polylysine concentrations were better than those chosen as 64,55 and 46 for the control of Staphylococcus aureus biofilm growth.