Laboratory of Research in Microbiology, Federal University of Piauí, Teresina, PI, Brazil.
Postgraduate Program in Pharmaceutical Sciences, Federal University of Piauí, Teresina, PI, Brazil.
Nat Prod Res. 2021 Feb;35(4):681-685. doi: 10.1080/14786419.2019.1590714. Epub 2019 Apr 2.
Microdilution assays were performed in order to evaluate the antimicrobial activity of the ethanoic extract from the leaves of (EEBF) against different microorganisms. The extract did not present inner antimicrobial activities against the tested strains. However, EEBF was able to modulate the norfloxacin-resistance against SA1199-B that overproduce the NorA efflux pump, once sub-inhibitory concentrations of EEBF reduced the minimal inhibitory concentratio of the norfloxacin in 87.5%. This modulatory effect was also found when the antibiotic was replaced by ethidium bromide, suggesting that EEBF acts probably by inhibition of NorA, allowing the antibiotic accumulation intracellularly, and making the line more sensitive. These results point out the EEBF potential as a source of NorA inhibitors that could be used in combination with norfloxacin for treatment of infections caused by multidrug-resistant .
为了评估（EEBF）叶乙醇提取物对不同微生物的抗菌活性，进行了微量稀释试验。该提取物对测试菌株没有内在的抗菌活性。然而，EEBF 能够调节耐诺氟沙星的 SA1199-B，该菌过度产生 NorA 外排泵，一旦 EEBF 的亚抑制浓度将诺氟沙星的最小抑菌浓度降低 87.5%。当用溴化乙锭代替抗生素时，也发现了这种调节作用，这表明 EEBF 可能通过抑制 NorA 起作用，允许抗生素在细胞内积累，从而使细菌对药物更敏感。这些结果表明，EEBF 可能是 NorA 抑制剂的来源，可与诺氟沙星联合用于治疗多药耐药菌引起的感染。
