Laboratory of Bioprospecting in the Semi-Arid and Alternative Methods (LABSEMA), Regional University of Cariri - URCA, Crato, 63105-000, CE, Brazil.
Laboratory of Bioprospecting in the Semi-Arid and Alternative Methods (LABSEMA), Regional University of Cariri - URCA, Crato, 63105-000, CE, Brazil; Biological Sciences Pos Graduate Program - PPGCB, Federal University of Pernambuco - UFPE, Recife, 50670-901, PE, Brazil.
Microb Pathog. 2022 Mar;164:105456. doi: 10.1016/j.micpath.2022.105456. Epub 2022 Feb 23.
The indiscriminate use of antibiotics contributes significantly to the selection of bacteria resistant to several antibiotics. Among the resistance mechanisms are the Efflux Pumps which are responsible for extruding solutes from the cell cytoplasm through proteins in the cell membrane. Because of this, new strategies are needed to control multidrug-resistant pathogenic strains. In this way, the objective of this study was to evaluate the antibacterial activity of eugenol by inhibition of TetK Efflux Pump in strains of Staphylococcus aureus resistant to Tetracycline, in addition to evaluating its toxicity in Drosophila melanogaster. To determine the Minimum Inhibitory Concentration (MIC), the broth microdilution method was used. The modulated effect of antibiotic and Ethidium Bromide associated with eugenol in subinhibitory concentrations (MIC/8) was evaluated. To evaluate the toxic effect of eugenol on D. melanogaster, fumigation tests were used, in which the parameters of mortality and damage to the locomotor system were evaluated. The results showed that eugenol has no direct activity in S. aureus, with an MIC ≥1024 μg/mL. However, it demonstrated that the synergistic potential when associated with Tetracycline, reducing the MIC of the antibiotic, already associated with Ethidium Bromide, had an antagonistic effect. When the toxicity in D. melanogaster was evaluated, eugenol demonstrated a non-toxic profile, since it presented EC50: 2036 μL/mL in 48 h of exposure. In conclusion, eugenol had no relevant direct effect against S. aureus, however, it potentialized the action of the antibiotic by decreasing its MIC.
抗生素的滥用是导致多种抗生素耐药细菌选择的主要原因之一。耐药机制之一是外排泵，它通过细胞膜中的蛋白质将细胞质中的溶质排出细胞。因此，需要新的策略来控制多药耐药的致病菌株。在这种情况下，本研究的目的是评估丁香酚通过抑制四环素耐药金黄色葡萄球菌中的 TetK 外排泵的抗菌活性，此外还评估了它在黑腹果蝇中的毒性。为了确定最小抑菌浓度（MIC），采用肉汤微量稀释法。评估了亚抑菌浓度（MIC/8）下抗生素和溴化乙锭与丁香酚联合的调制作用。为了评估丁香酚对 D. melanogaster 的毒性作用，使用熏蒸试验，评估了死亡率和运动系统损伤的参数。结果表明，丁香酚对金黄色葡萄球菌没有直接活性，MIC≥1024μg/mL。然而，它表明与四环素联合具有协同潜力，降低了抗生素的 MIC，已经与溴化乙锭联合，具有拮抗作用。当评估 D. melanogaster 的毒性时，丁香酚表现出非毒性特征，因为在 48 小时的暴露中，EC50：2036μL/mL。总之，丁香酚对金黄色葡萄球菌没有直接的相关作用，但通过降低其 MIC 增强了抗生素的作用。
