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Backgrounds: Due to the emergence of multidrug-resistant Candida species, the discovery of new antifungal agents with minimum side effects is essential. The aim of this study was to investigate the antifungal activity of caprylic acid and nano-encapsulated caprylic acid against C. albicans as well as their effect on the expression of EFG1 gene.
Materials & Methods: In this laboratory trial study, the minimum inhibitory concentration (MIC) of caprylic acid and nano-encapsulated caprylic acid against C. albicans was evaluated at various concentrations (400-625 and 1.3-50 μL/mL, respectively). Real time-PCR was performed to assess the expression level of EFG1 gene. Cytotoxicity effect of caprylic acid and nano-encapsulated caprylic acid was evaluated on SW480 cell line using MTT test.
Findings: Antifungal activity findings displayed that MIC90 and MIC50 values of caprylic acid were 500 and 450 μg/mL, respectively, whereas MIC90 and MIC50 values of nano-encapsulated caprylic acid were 6.2 and 3.1 μg/mL, respectively. The expression of EFG1 gene significantly decreased in the groups treated with caprylic acid and nano-encapsulated caprylic acid compared to the control group. According to the cytotoxicity evaluation findings, the viability of cells treated with caprylic acid was significantly higher than that of cells exposed to nano-encapsulated caprylic acid.
Conclusions: According to the obtained results, nano-encapsulated caprylic acid successfully inhibited C. albicans growth at a lower concentration compared to caprylic acid. Overall, it was found that nano-encapsulated caprylic acid is a promising antifungal agent against Candida species; however, further studies are needed to be performed about nano-encapsulation of caprylic acid.