穿心莲内酯抗铜绿假单胞菌生物被膜及与阿奇霉素协同抗菌作用

目的研究穿心莲内酯抗铜绿假单胞菌生物被膜及与阿奇霉素协同抗菌作用。方法微量倍比稀释法测定穿心莲内酯对铜绿假单胞菌的最小抑菌浓度（MIC）,棋盘稀释法测定穿心莲内酯和阿奇霉素协同抗菌作用,MTT法测定穿心莲内酯对铜绿假单胞菌生物被膜的最小抑膜浓度（SMIC）,显微镜下观察药物对生物膜形态的影响。结果穿心莲内酯对铜绿假单胞菌的MIC 50μg/mL,和阿奇霉素有协同抗菌作用。穿心莲内酯对铜绿假单胞菌生物被膜的SMIC501天25μg/mL、3天25μg/mL、7天50μg/mL;SMIC801天50μg/mL、3天50μg/mL、7天100μg/mL,形态观察提示穿心莲内酯SMIC80浓度对铜绿假单胞菌生物被膜的抑制作用明显。结论穿心莲内酯具有抗铜绿假单胞菌生物被膜作用,对阿奇霉素也有协同抗菌作用。

Effect of andrographolide against Pseudomonas aeruginosa biofilm and its synergistic antibacterial activity in combination with azithromycin

Objective To investigate the effects of Andrographolide against Pseudomonas aeruginosa biofilms and synergistic antibacterial activity in combination with Azithromycin.Method Microdilution assay was used to detect MIC of Andrographolide to Pseudomonas aeruginosa;checkerboard method was used to examine the synersism of Andrographolide and Azithromycin;MTT assay was used to detect SMIC of Andrographolide against Pseudomonas aeruginosa biofilms,and microscope was used to observe morphology of biofilms treated with the two drugs.Result The MIC of Andrographolide to Pseudomonas aeruginosa was 50 μg/mL,and andrographolide synergized with Azithromycin.The SMICs50 of Andrographolide against Pseudomonas aeruginosa biofilms at 1 d,3 d and 7 d were 25 μg/mL,25 μg/mL and 50 μg/mL,respectively,while SMICs80 were 50 μg/mL,50 μg/mL and 100 μg/mL,respectively.Morphologically Andrographolide inhibited Pseudomonas aeruginosa biofilms evidently at the concentration of SMIC80.Conclusion Andrographolide can inhibit Pseudomonas aeruginosa biofilms,and synergize with Azithromycin.