Lorenzi Claudia, Lio Fabrizio, Mazzetti Vincenzo, Carosi Paolo, Lamelza Stefano, Pistoia Enrico Salvatore, Pica Francesca, Gaziano Roberta
Department of Chemical Science and Technologies, University of Rome Tor Vergata, 00133 Rome, Italy.
Department of Clinical Sciences and Translational Medicine, School of Dentistry, University of Rome Tor Vergata, 00133 Rome, Italy.
Dent J (Basel). 2024 Sep 27;12(10):307. doi: 10.3390/dj12100307.
To evaluate the potential synergistic activity of metronidazole (MTZ) and chlorhexidine (CHX) against growth. Antimicrobial susceptibility tests of to MTZ and CHX were performed on in vitro serial 2-fold dilutions of MTZ (from 1 mg/mL to 0.015 mg/mL) and CHX (from 1 mg/mL to 0.03 mg/mL) in thioglycollate medium broth in a 96-well plate. The turbidity of each sample was analyzed by absorbance spectrophotometry at 450 nm wavelengths by using an enzyme-linked immunosorbent assay (ELISA) reader. The MIC50 (minimum inhibitory concentration) and MBC (minimum bactericidal concentration) were assessed. To investigate the potential synergism between MTZ and CHX, bacterial cells were treated with MTZ or CHX, as described above, either alone or in combination. The MIC of MTZ was 0.03 mg/mL while that of CHX ranged from 0.12 to 0.06 mg/mL. MTZ and CHX exerted a significant inhibitory effect on growth in a dose-dependent manner. MTZ at a low and ineffective concentration of 0.015 mg/mL, associated with a suboptimal concentration of CHX (0.03 mg/mL), exhibited a significant synergistic inhibitory effect on bacterial growth (50% inhibition vs. control) ( < 0.001), and the effect was more remarkable with 0.06 mg/mL CHX (75% inhibition vs. control). CHX and MTZ showed a significant synergistic effect against growth. A non-effective concentration of MTZ (0.015 mg/mL) combined with suboptimal concentrations of CHX (0.03 mg/mL and 0.06 mg/mL) were related to a 50% growth in the inhibition and 99.99% death of , respectively. The applicability of the clinical use of these concentrations should be tested in randomized controlled trials.
评估甲硝唑（MTZ）和氯己定（CHX）对[具体细菌名称未给出]生长的潜在协同活性。在96孔板中，于硫乙醇酸盐培养基肉汤中对MTZ（从1 mg/mL至0.015 mg/mL）和CHX（从1 mg/mL至0.03 mg/mL）进行体外系列2倍稀释，对[具体细菌名称未给出]进行针对MTZ和CHX的药敏试验。使用酶联免疫吸附测定（ELISA）读数仪通过在450 nm波长下的吸光度分光光度法分析每个样品的浊度。评估最小抑菌浓度（MIC50）和最小杀菌浓度（MBC）。为研究MTZ和CHX之间的潜在协同作用，如上述单独或联合用MTZ或CHX处理细菌细胞。MTZ的MIC为0.03 mg/mL，而CHX的MIC范围为0.12至0.06 mg/mL。MTZ和CHX对[具体细菌名称未给出]生长呈剂量依赖性显著抑制作用。低浓度且无效的0.015 mg/mL的MTZ与次优浓度的CHX（0.03 mg/mL）联合，对细菌生长表现出显著的协同抑制作用（与对照相比50%抑制）（P<0.001），而CHX浓度为0.06 mg/mL时效果更显著（与对照相比75%抑制）。CHX和MTZ对[具体细菌名称未给出]生长显示出显著的协同作用。无效浓度的MTZ（0.015 mg/mL）与次优浓度的CHX（0.03 mg/mL和0.06 mg/mL）联合，分别导致[具体细菌名称未给出]生长抑制50%和死亡99.99%。这些浓度在临床应用中的适用性应在随机对照试验中进行测试。
