Fayolle Karine, Girard Claire, Lasfargues Pauline, Koteich Sahar, Kerros Sylvain
INRAE, VetAgro Sup Campus Agronomique de Lempdes, UMR F, Université Clermont Auvergne, 15000 Aurillac, France.
Microlab-Phytosynthese, 63200 Mozac, France.
Microorganisms. 2025 May 14;13(5):1125. doi: 10.3390/microorganisms13051125.
With the increasing occurrence of bacterial resistance, it is now essential to look for new alternatives to protect the curative utilization of antibiotics within the One Health concept. Here, we adapt and optimize a broth microdilution method and compare it against the broth macrodilution method for evaluating the antibacterial activity of a complex essential oils mix (EO mix) against four livestock pathogens: , , , and Microdilution method performance (final volume well: 300 µL; inoculum: 1.0 × 10 CFU/mL) was evaluated following CLSI recommendations, by comparing the MIC of each of the four strains with the MICs obtained with the macrodilution method (final volume tube: 2 mL; inoculum 1.0 × 10 CFU/mL). Microdilution analysis was performed with an automated plate reader (Bioscreen C), and three bacterial growth parameters (OD max, lag phase, and growth rate) were calculated (DMFit curve-fitting software (v2.1; courtesy of the Institute of Food Research, Norwich, UK)). EO mix MICs were determined for , , and . Our results emphasize the importance of ensuring the accuracy of MIC results by performing three technical and three biological replicates, and combining OD max, lag phase, and growth rate to assess the impact of an EO mix at sub-MIC levels.
随着细菌耐药性的日益增加，在“同一健康”理念下寻找新的方法来保障抗生素的有效使用变得至关重要。在此，我们对肉汤微量稀释法进行了调整和优化，并将其与肉汤常量稀释法进行比较，以评估一种复合精油混合物（EO混合物）对四种家畜病原体（ 、 、 、 ）的抗菌活性。微量稀释法的性能（每孔最终体积：300 μL；接种物：1.0×10 CFU/mL）按照美国临床和实验室标准协会（CLSI）的建议进行评估，通过将四种菌株各自的最低抑菌浓度（MIC）与常量稀释法（试管最终体积：2 mL；接种物1.0×10 CFU/mL）获得的MIC进行比较。使用自动酶标仪（Bioscreen C）进行微量稀释分析，并计算三个细菌生长参数（最大光密度、延迟期和生长速率）（使用DMFit曲线拟合软件（v2.1；由英国诺维奇食品研究所提供））。测定了 、 、 的EO混合物MIC。我们的结果强调了通过进行三次技术重复和三次生物学重复，并结合最大光密度、延迟期和生长速率来评估亚MIC水平下EO混合物的影响，以确保MIC结果准确性的重要性。
