Combined effect of Cinnamomum zeylanicum blume essential oil and nystatin on Candida albicans growth and micromorphology
Authors: Castro Ricardo Dias de , Lima Edeltrudes De Oliveira , Freires Irlan De Almeida , Alves Livia Araújo 
Published: April 2018

<p class="MsoNormal" style="text-align: justify; line-height: 150%;"><span style="font-size: 15.555556297302246px; line-height: 23.33333396911621px;">Introduction: The combination of a natural product and a synthetic antifungal may lead to a lower dose of each individual agent and </span><span style="font-size: 15.555556297302246px; line-height: 23.33333396911621px;">consequent reduction of adverse effects and greater pharmacological synergism. Objective: This study investigated the antifungal</span></p><p class="MsoNormal" style="text-align: justify; line-height: 150%;"><span style="font-size: 15.555556297302246px; line-height: 23.33333396911621px;">activity of the essential oil (EO) from Cinnamomum zeylanicum Blume alone and combined with nystatin on Candida albicans growth </span><span style="font-size: 15.555556297302246px; line-height: 23.33333396911621px;">and micromorphology. Methodology: We determined the Minimum Inhibitory Concentration (MIC), Fractional Inhibitory Concentration </span><span style="font-size: 15.555556297302246px; line-height: 23.33333396911621px;">Index (FIC) and the effect of the EO alone and combined with nystatin on the growth kinetics and production of virulence-related </span><span style="font-size: 15.555556297302246px; line-height: 23.33333396911621px;">structures by the yeasts, such as pseudohyphae and chlamydoconidia. Results: When tested alone, the EO from C. zeylanicum and</span></p><p class="MsoNormal" style="text-align: justify; line-height: 150%;"><span style="font-size: 15.555556297302246px; line-height: 23.33333396911621px;">nystatin showed MIC of 312.5 μg/ml and 64 μg/ml, respectively. When combined, MIC values decreased to 39 μg/ml and 32 μg/</span><span style="font-size: 15.555556297302246px; line-height: 23.33333396911621px;">ml for the EO and nystatin, respectively. The value of the Fractional Concentration Index (FIC) was 0.6024, indicating additivity. It </span><span style="font-size: 15.555556297302246px; line-height: 23.33333396911621px;">could be observed that at all concentrations the products tested alone and in combination were able to reduce the number of CFU/</span><span style="font-size: 15.555556297302246px; line-height: 23.33333396911621px;">mL, when compared to the control group (p<0.0001) from 30 min. In addition, both the products alone and combined inhibited </span><span style="font-size: 15.555556297302246px; line-height: 23.33333396911621px;">production of pseudohyphae and chlamydoconidia compared to the control. Conclusion: The combination between the essential oil</span></p><p class="MsoNormal" style="text-align: justify; line-height: 150%;"><span style="font-size: 15.555556297302246px; line-height: 23.33333396911621px;">from C. zeylanicum and nystatin potentiated the inhibitory effect on C. albicans growth. Furthermore, it reduced the production of </span><span style="font-size: 15.555556297302246px; line-height: 23.33333396911621px;">pathogenicity-related morphological structures such as pseudohyphae and chlamydoconidia.</span></p><p class="MsoNormal" style="text-align: justify; line-height: 150%;"><span style="font-size: 15.555556297302246px; line-height: 23.33333396911621px;">Key-words: Cinnamomum zeylanicum. Nystatin. Essential Oil. Natural Product. Drug synergism.</span></p>