Antifungal activity of polyphenolic compounds against fluconazole- susceptible and -resistant Candida species

Harmed  Fakhim; Bahar  Mohamadi; Shima  Gharibi; Medhi  Rahimmalek; Mahnaz Hosseini  Rizi; Mahsa  Shelerangkon; Elahe  Nasri; Fariba  Dorostkar; Antoni  Szumny; Afsane  Vaezi

doi:10.18502/ijm.v17i2.18398

Harmed Fakhim Infectious Diseases and Tropical Medicine Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
Bahar Mohamadi Department of Microbiology, Tehran North Branch, Islamic Azad University, Tehran, Iran
Shima Gharibi Infectious Diseases and Tropical Medicine Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
Medhi Rahimmalek Department of Horticulture, College of Agriculture, Isfahan University of Technology, Isfahan, Iran
Mahnaz Hosseini Rizi Infectious Diseases and Tropical Medicine Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
Mahsa Shelerangkon Infectious Diseases and Tropical Medicine Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
Elahe Nasri Infectious Diseases and Tropical Medicine Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
Fariba Dorostkar Department of Medical Laboratory Sciences, School of Allied Medical Sciences, Iran University of Medical Sciences, Tehran, Iran
Antoni Szumny Department of Food Chemistry and Biocatalysis, Wrocław University of Environmental and Life Sciences, Wroclaw, Poland
Afsane Vaezi Department of Medical Laboratory Sciences, School of Allied Medical Sciences, Iran University of Medical Sciences, Tehran, Iran

DOI: https://doi.org/10.18502/ijm.v17i2.18398

Keywords: Tannic acid; Polyphenolic compounds; Candida species; Fluconazole resistance; Antifungal activity

Abstract

Background and Objectives: The rapid emergence of resistant fungi is occurring worldwide, and this crisis has been attributed to the lack of new antifungal drug development. This issue emphasizes the need for innovation in finding novel antifungals. There is an increasing interest in using the natural products of plants with high biological activity as alternatives to synthetic drugs. This study aimed to evaluate the possible applicability of polyphenols as alternative antifungal drugs to treat resistant Candida infections.

Materials and Methods: A panel of fluconazole-resistant (n=14) and fluconazole-susceptible (n=26) clinical Candida iso- lates was obtained from the reference culture collection. The determination of the minimum inhibitory concentrations (MICs) of fluconazole, tannic acid, rosmarinic acid, gallic acid, chlorogenic acid, caffeic, ferulic, and p-coumaric was carried out following the Clinical and Laboratory Standards Institute (CLSI) guidelines.

Results: The MIC values of 40 Candida species isolates ranged from 0.25 to >64 µg/mL for polyphenolic compounds. The highest inhibitory effect against Candida species was observed with tannic acid, followed by fluconazole. Non-albicans Candida groups were more sensitive to tannic acid compared to C. albicans isolates. Significant differences were observed in the MICs of fluconazole and tannic acid against non-albicans Candida isolates.

Conclusion: The increasing antifungal resistance highlights the importance of evaluating new drugs that are more robust against resistance. This study suggests that tannic acid could be considered a novel antifungal agent for managing fungal infections, including multidrug-resistant non-albicans Candida infections.