Abstract This study aimed to evaluate the effect of diclofenac on minimum inhibitory concentrations of antifungals against planktonic cells and biofilms of Candida tropicalis. Susceptibility testing of planktonic cells was evaluated using the broth microdilution assay and checkerboard method. Biofilm formation by C. tropicalis in the presence of diclofenac, alone or in combination with antifungals, was also evaluated, and scanning electron microscope (SEM) and confocal microscope (CLSM) analyses were performed. Diclofenac showed an MIC of 1024 μg ml−1 against planktonic cells. The MICs of fluconazole and voriconazole against azole-resistant isolates were reduced 8- to 32-fold and 16- to 256-fold, respectively, when in combination with diclofenac. When in combination with fluconazole or voriconazole, diclofenac reduced the antifungal concentration necessary to inhibit C. tropicalis biofilm formation. In conclusion, diclofenac presents synergism with fluconazole and voriconazole against resistant C. tropicalis strains and improves the activity of these azole drugs against biofilm formation.

中文翻译：

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双氯芬酸与唑类对热带念珠菌的浮游细胞和生物膜具有协同作用

摘要 本研究旨在评估双氯芬酸对热带念珠菌浮游细胞和生物膜的抗真菌药物最低抑制浓度的影响。使用肉汤微量稀释法和棋盘法评估浮游细胞的敏感性测试。还评估了热带念珠菌在双氯芬酸存在下，单独或与抗真菌剂联合使用时的生物膜形成，并进行了扫描电子显微镜 (SEM) 和共聚焦显微镜 (CLSM) 分析。双氯芬酸对浮游细胞的 MIC 为 1024 μg ml-1。当与双氯芬酸联合使用时，氟康唑和伏立康唑对唑类耐药菌株的 MIC 分别降低了 8 至 32 倍和 16 至 256 倍。当与氟康唑或伏立康唑合用时，双氯芬酸降低了抑制热带念珠菌生物膜形成所需的抗真菌浓度。总之，双氯芬酸与氟康唑和伏立康唑对耐药热带念珠菌菌株具有协同作用，并提高了这些唑类药物对生物膜形成的活性。