摘要
目的本实验研究了罗红霉素对铜绿假单胞菌生物被膜合成的抑制及其与亚胺培南的抗菌增效作用。方法色氨酸法测定多糖蛋白复合物(GLX);噻唑兰法测定活菌数。结果1/16MIC、1/4MIC的罗红霉素可以显著抑制细菌生物被膜多糖蛋白复合物的合成。1/16MIC、1/4MIC的罗红霉素可以显著增强1/4MIC,1/2MIC及1MIC的亚胺培南对生物被膜细菌的抑菌活性。结论罗红霉素本身对铜绿假单胞菌并无抑菌活性而可以抑制多糖蛋白复合物的合成,显示罗红霉素能提高亚胺培南对生物被膜的渗透从而增强其对铜绿假单胞菌生物被膜的抑菌活性。
Objective The influence of roxythrgmycin （RXM） on the production of glycocalyx （GLX） from P. aeruginosa biofilms and synergism of antibacterial activities of RXM and imipenem （IMI） to P. aerugirtasa in biofilms was investigated. Methods GLX production was measured by using a L-tryptophan method and viable counts in biofilms was determined by using a methylthiazolyhetrazolium （MTT） method Results GLX production was reduced significantly from 32.5 ± 15.7 μg/ml at 0MIC to 24.3 ± 13.3 μg/ml at 1/16MIC and 18.6 ± 9.5μg/ml at 1/4MIC respectively （ P 〈 0.05 ）. 1/16MIC and 1/4MIC RXM showed no bactericidal activities to P. aeruginosa in biofilms. Viable counts in biofilms were 6.8 ±0.2LgCFU/cm2 at 0MIC, 6.7 ±0.2LgCFU/cm2 at 1/16MIC and 6.7 ± 0. 3LgCFU/cm2 at 1/4 MIC respectively （P 〉0.05 ）. However, RXM could enhance bactericidal activity of IMI to P. aeruginosa in biofilms. When 1/4MIC IMI was combined with I/4MIC and 1/16MIC RXM, viable counts decreased significantly from 6.7 ± 0.3 LgCFU/cm2 to 6.3 ,± O. 4 LgCFU/cm2 and 6.1 ± 0.5 LgCFU/cm2 respectively （ P 〈 0.05 ）. When 1/2MIC IMI was combined with 1/4MIC and 1/16MIC RXM, viable counts decreased significantly from 6.6 ± 0.3 LgCFU/cm2 to 6. 3 ± 0.5LgCFU/cm2 and 6. 1 ± 0.4LgCFU/cm2 respectively （ P 〈 0.05 ）, When 1MIC IMI was combined with 1/4MIC and 1/16MIC RXM, viable counts decreased significantly from 6.4 ±0.5LgCFU/cm2 to 5.6 ± 0.8LgCFU/cm2 and 5.0 -± 0.7LgCFU/cm2 respectively （ P 〈 0.05 ）. Conclusion Since RXM did not have direct bactericidal activity to P. aeruginosa in biofilms but could inhibit GLX production, we considered that RXM could enhance antibacterial activity of IMI by enhancing permeability of IMI into biofilms.
出处
《中国抗生素杂志》
CAS
CSCD
北大核心
2009年第11期688-690,共3页
Chinese Journal of Antibiotics
