FREE SHIPPING over $40
OVER 9000 FIVE-STAR REVIEWS
5% OFF ALL SUBSCRIPTIONS
100% HAPPINESS GUARANTEE
Analyze Diet
0
Home / Equine Research Bank / Equine Vet J / In vitro synergy of eugenol on the antifungal effects of vor...
Equine veterinary journal2020; 53(1); 94-101; doi: 10.1111/evj.13268

In vitro synergy of eugenol on the antifungal effects of voriconazole against Candida tropicalis and Candida krusei strains isolated from the genital tract of mares.

Abstract: Due to the limited range of antifungals available to treat genital Candida infections and the emergence of resistant isolates, attention has focused on the antifungal potency of natural compounds with promising biological properties. Objective: To examine whether eugenol synergises the in vitro efficacy of voriconazole against Candida strains isolated from the genital tract of mares. Methods: In vitro experiment. Methods: The antifungal activity of eugenol and voriconazole was evaluated using the broth microdilution assay (CLSI- M27-A3). Synergism of eugenol and voriconazole against genital Candida isolates was evaluated by the microdilution checkerboard method. Results: Minimum inhibitory concentration (MIC) values for eugenol and voriconazole ranged from 400 to 800 µg/mL and 1 to 8 µg/mL, respectively, for C. tropicalis isolates, and from 200 to 400 µg/mL for eugenol and 2 to 16 µg/mL for voriconazole against C. krusei isolates. Eugenol decreased the arithmetic mean MIC for voriconazole against C. tropicalis and C. krusei isolates from 2.66 to 0.46 µg/mL and 7.77 to 0.41 µg/mL respectively. The fractional inhibitory concentration index (FICI) values for the eugenol-voriconazole combination ranged from 0.25 to 0.88 and 0.19 to 0.63 for C. tropicalis and C. krusei isolates respectively. A synergistic effect of eugenol in combination with voriconazole was observed for 83.3% of C. tropicalis and 77.7% of C. krusei isolates. Antagonistic activity was not seen in any of the isolates tested. Conclusions: Since in vitro antifungal susceptibility tests are not systematic analyses, any selection bias could influence the results. In addition, in vitro susceptibility does not uniformly predict clinical success in vivo. Conclusions: Eugenol showed fungistatic and fungicidal effects against genital Candida isolates and, in combination, synergised the antifungal effects of voriconazole. The eugenol-voriconazole combination can lay the foundation for a therapeutic approach against isolates in which azole resistance has increased over time.
© 2020 EVJ Ltd.
Get Full Text
Publication Date: 2020-04-30 PubMed ID: 32298479DOI: 10.1111/evj.13268Google Scholar: Lookup
The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.
LinkedInCopy
  • Journal Article

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

The research investigates the combined antifungal effects of eugenol and voriconazole on Candida strains found in the genital tract of mares. The study found that this combination presents a significant increase in antifungal effectiveness, suggesting a new potential therapeutic approach.

Objectives and Methods

  • The study aimed to check if eugenol, a natural compound known for its robust biological properties, enhances the antifungal efficacy of voriconazole when acted against Candida strains isolated from the genital tract of mares.
  • The researchers conducted in vitro experiments using a method known as the broth microdilution assay (CLSI- M27-A3) to evaluate the antifungal activity of eugenol and voriconazole.
  • To investigate the combined effect of eugenol and voriconazole, the scientists used the microdilution checkerboard method.

Results

  • The study found that the minimum inhibitory concentration (MIC) values for eugenol and voriconazole varied depending on the Candida strain.
  • If used together, eugenol considerably lowered the arithmetic mean MIC for voriconazole against both Candida strains.
  • The fractional inhibitory concentration index (FICI) values for the eugenol-voriconazole combination suggested that eugenol can synergize the antifungal effects of voriconazole.
  • About 80% of both Candida strains showed a synergistic response to the eugenol-voriconazole combination, pointing towards increased antifungal potency.

Conclusions

  • The researchers admit that in vitro antifungal susceptibility tests are not systematic analyses and that any selection bias could affect the results. They further note that in vitro susceptibility does not uniformly predict clinical success in vivo.
  • Despite these limitations, the research concludes that eugenol shows fungistatic (inhibits fungal growth) and fungicidal (kills fungi) effects against genital Candida isolates.
  • The addition of eugenol significantly improved the antifungal effects of voriconazole and could provide a foundation for a new therapeutic strategy against isolates experiencing increasing azole resistance.

Cite This Article

APA
Sharifzadeh A, Shokri H. (2020). In vitro synergy of eugenol on the antifungal effects of voriconazole against Candida tropicalis and Candida krusei strains isolated from the genital tract of mares. Equine Vet J, 53(1), 94-101. https://doi.org/10.1111/evj.13268

Publication

Equine veterinary journal
ISSN: 2042-3306
NlmUniqueID: 0173320
Country: United States
Language: English
Volume: 53
Issue: 1
Pages: 94-101

Researcher Affiliations

Sharifzadeh, Aghil
  • Mycology Research Center, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran.
Shokri, Hojjatollah
  • Department of Pathobiology, Faculty of Veterinary Medicine, Amol University of Special Modern Technologies, Amol, Iran.

MeSH Terms

  • Animals
  • Antifungal Agents / pharmacology
  • Candida tropicalis
  • Drug Resistance, Fungal
  • Eugenol / pharmacology
  • Female
  • Genitalia
  • Horses
  • Microbial Sensitivity Tests / veterinary
  • Pichia
  • Voriconazole / pharmacology

Grant Funding

  • Amol University of Special Modern Technologies
  • University of Tehran

References

This article includes 37 references
  1. Stout TAE. Fungal endometritis in the mare.. Pferdeheilkunde 2008;24:83-7.
  2. Azarvandi A, Khosravi AR, Shokri H, Talebkhan Garoussi M, Gharagouzlou F, Vahedi G. Presence and distribution of yeasts in the reproductive tract in healthy female horses.. Equine Vet J 2016;49:614-61.
  3. Rozanski P, Slaska B, Rozanska D. The current status of prevalence of yeast-like fungi in the environment of horses breeding in Poland.. Ann Anim Sci 2013;13:365-74.
  4. Stefanetti V, Marenzoni ML, Lepri E, Coletti M, Proietti PC, Agnetti F. A case of Candida guilliermondii abortion in an Arab mare.. Med Mycol Case Rep 2014;4:19-22.
  5. Coutinho da Silva MA, Alvarenga MA. Fungal endometritis.. In:McKinnon AO, Squires EL, Vaala WE, Varner DD, editors. Equine reproduction, 2nd edn. Philadelphia, Pennsylvania: Blackwell Publishing; 2010. p. 2643-51.
  6. Aitken GJ. Subclinical fungal endometritis in an 8-year-old Hanoverian mare.. Can Vet J 2012;53:196-8.
  7. Samanta I. Veterinary mycology.. New Delhi: Springer; 2015. p. 201-2.
  8. Sharifzadeh A, Shokri H, Abbaszadeh S. Interaction of carvacrol and voriconazole against drug- resistant Candida strains isolated from patients with candidiasis.. J Mycol Med 2019;29:44-8.
  9. Whaley SG, Berkow EL, Rybak JM, Nishimoto AT, Barker KS, Rogers PD. Azole antifungal resistance in Candida albicans and emerging non-albicans Candida species.. Front Microbiol 2016;7:2173.
  10. Louie GV, Baiga TJ, Bowman ME, Koeduka T, Taylor JH, Spassova SM. Structure and reaction mechanism of basil eugenol synthase.. PLoS ONE 2007;2:e993.
  11. Carrasco H, Raimondi M, Svetaz L, Di Liberto M, Rodriguez MV, Espinoza L. Antifungal activity of eugenol analogues. Influence of different substituents and studies on mechanism of action.. Molecules 2012;17:1002-24.
  12. Perugini Biasi-Garbin R, Saori Otaguiri E, Morey AT, Fernandes da Silva M, Belotto Morguette AE, Lancheros AC. Effect of eugenol against Streptococcus agalactiae and synergistic interaction with biologically produced silver nanoparticles.. Evid Based Complement. Alternat Med 2015;2015:861497.
  13. Darvishi E, Omidi M, Bushehri AA, Golshani A, Smith ML. The antifungal eugenol perturbs dual aromatic and branched-chain amino acid permeases in the cytoplasmic membrane of yeast.. PLoS ONE 2013;8:e76028.
  14. Clinical Laboratory Standards Institute (CLSI). Reference method for broth dilution antifungal susceptibility testing of yeasts.. 3rd edn. Wayne, PA: Clinical and Laboratory Standards Institute; [Approved standard. CLSI document M27-A3]. 2008.
  15. De Castro RD, De Souza TMPA, Bezerra LMD, Ferreira GLS, de Brito Costa EMM, Cavalcanti AL. Antifungal activity and mode of action of thymol and its synergism with nystatin against Candida species involved with infections in the oral cavity: an in vitro study.. BMC Complement Alternat Med 2015;15:417.
  16. Baeder DY, Yu G, Hozé N, Rolff J, Regoes RR. Antimicrobial combinations: bliss independence and Loewe additivity derived from mechanistic multi-hit models.. Philos Trans R Soc Lond B Biol Sci 2016;371:20150294.
  17. Odds FC. Synergy, antagonism, and what the chequerboard puts between them.. J Antimicrob Chemother 2003;52:1.
  18. Sharifzadeh A, Soltani M, Shokri H. Evaluation of virulence factors and antifungal susceptibility patterns of different Candida species isolated from the female camel (Camelus dromedarius) genital tract.. Mycoses 2015;58:478-84.
  19. Kronvall G, Karlsson A. Fluconazole and voriconazole multidisk testing of Candida species for disk test calibration and MIC estimation.. J Clin Microbiol 2001;39:1422-8.
  20. Mandras N, Tullio V, Allizond V, Scalas D, Banche G, Roana J. In vitro activities of fluconazole and voriconazole against clinical isolates of Candida spp. determined by disk diffusion testing in Turin, Italy.. Antimicrob Agents Chemother 2009;53:1657-9.
  21. Giguère S. Antifungal chemotherapy.. In: Giguère S, Prescott JF, Baggot JD, editors. Antimicrobial therapy in veterinary medicine. 4th ed. Ames, Iowa: Blackwell Publishing; 2006; p. 301-22.
  22. Bopp LH, Baltch AL, Ritz WJ, Michelsen PB, Smith RP. Antifungal effect of voriconazole on intracellular Candida glabrata, Candida krusei and Candida parapsilosis in human monocyte-derived macrophages.. J Med Microbiol 2006;55:865-70.
  23. Beltaire KA, Cheong SH, da Silva M. Retrospective study on equine uterine fungal isolates and antifungal susceptibility patterns (1999-2011).. Equine Vet J 2012;44:84-7.
  24. Ahmad A, Wani MY, Khan A. Synergistic interactions of eugenol-tosylate and its congeners with fluconazole against Candida albicans.. PLoS ONE 2015;10:e0145053.
  25. Marcos-Arias C, Eraso E, Madariaga K, Quindós G. In vitro activities of natural products against oral Candida isolates from denture wearers.. BMC Complement Alternat Med 2011;11:119.
  26. Gallucci M, Carezzano M, Oliva M. In vitro activity of natural phenolic compounds against fluconazole-resistant Candida species: a quantitative structure-activity relationship analysis.. J Appl Microbiol 2014;116:795-804.
  27. Bennis S, Chami F, Chami N. Surface alteration of Saccharomyces cerevisiae induced by thymol and eugenol.. Lett Appl Microbiol 2004;38:454-8.
  28. Braga P, Dal Sasso M, Culici M, Alfieri M. Eugenol and thymol, alone or in combination, induce morphological alterations in the envelope of Candida albicans.. Fitoterapia 2007;78:396-400.
  29. Marchese A, Barbieri R, Coppo E, Orhan IE, Daglia M, Nabavi SF. Antimicrobial activity of eugenol and essential oils containing eugenol: a mechanistic viewpoint.. Crit Rev Microbiol 2017;43:1-22.
  30. Ahmad A, Khan A, Yousuf S. Proton translocating ATPase mediated fungicidal activity of eugenol and thymol.. Fitoterapia 2010;81:1157-62.
  31. Coutinho HD, Costa JG, Lima EO. Herbal therapy associated with antibiotic therapy: potentiation of the anti-biotic activity against methicillin-resistant Staphylococcus aureus by Turnera ulmifolia L.. BMC Complement Alternat Med 2009;9:13.
  32. Bassole IHN, Juliani HR. Essential oils in combination and their antimicrobial properties.. Molecules 2012;17:3989-4006.
  33. Ahmad A, Khan A, Khan LA, Manzoor N. In vitro synergy of eugenol and methyleugenol with fluconazole against clinical Candida isolates.. J Med Microbiol 2010;59:1178-84.
  34. Pemmaraju SC, Pruthi PA, Prasad R, Pruthi V. Candida albicans biofilm inhibition by synergistic action of terpenes and fluconazole.. Indian J Exp Biol 2013;51:1032-7.
  35. Alves JCO, Ferreira GF, Santos JR, Silva LCN, Rodrigues JFS, Neto WRN. Eugenol induces phenotypic alterations and increases the oxidative burst in Cryptococcus.. Front Microbiol 2017;8:2419.
  36. Da Silva ICG, Santos HBP, Cavalcanti YW, Nonaka CFW, de Sousa SA, de Castro RD. Antifungal activity of eugenol and its association with nystatin on Candida albicans.. Pesqui Bras Odontopediatria Clin Integr 2017;17:e3235.
  37. Cross EW, Park S, Perlin DS. Cross-resistance of clinical isolates of Candida albicans and Candida glabrata to over-the-counter azoles used in the treatment of vaginitis.. Microb Drug Resist 2000;6:155-61.

Citations

This article has been cited 9 times.
  1. Taghipour Z, Bahmanzadeh M, Rahimi R. The Effects of Clove and Its Constituents on Reproductive System: a Comprehensive Review. Reprod Sci 2023 Apr 11;.
    doi: 10.1007/s43032-023-01223-xpubmed: 37040058google scholar: lookup
  2. Sen P, Gupta L, Vijay M, Vermani Sarin M, Shankar J, Hameed S, Vijayaraghavan P. 4-Allyl-2-methoxyphenol modulates the expression of genes involved in efflux pump, biofilm formation and sterol biosynthesis in azole resistant Aspergillus fumigatus. Front Cell Infect Microbiol 2023;13:1103957.
    doi: 10.3389/fcimb.2023.1103957pubmed: 36816579google scholar: lookup
  3. Biernasiuk A, Baj T, Malm A. Clove Essential Oil and Its Main Constituent, Eugenol, as Potential Natural Antifungals against Candida spp. Alone or in Combination with Other Antimycotics Due to Synergistic Interactions. Molecules 2022 Dec 26;28(1).
    doi: 10.3390/molecules28010215pubmed: 36615409google scholar: lookup
  4. Didehdar M, Chegini Z, Shariati A. Eugenol: A novel therapeutic agent for the inhibition of Candida species infection. Front Pharmacol 2022;13:872127.
    doi: 10.3389/fphar.2022.872127pubmed: 36016558google scholar: lookup
  5. Ulanowska M, Olas B. Biological Properties and Prospects for the Application of Eugenol-A Review. Int J Mol Sci 2021 Apr 1;22(7).
    doi: 10.3390/ijms22073671pubmed: 33916044google scholar: lookup
  6. Zhao Y, Liu Y, Tao J, Cao J, Lin Y, He Q, Fang X, Yun S, Du M, Su S, Bao T, Bai D, Zhang X, Dugarjaviin M. Isolation, identification and comparative genomic analysis of Lactobacillus salivarius from Mongolian horse vagina. Front Microbiol 2025;16:1635639.
    doi: 10.3389/fmicb.2025.1635639pubmed: 40822386google scholar: lookup
  7. Kong AS, Lim SE, Cheng WH, Yuswan MH, Tan NP, Lai KS. Harnessing Monoterpenes and Monoterpenoids as Weapons against Antimicrobial Resistance. Pol J Microbiol 2025 Mar 1;74(1):1-18.
    doi: 10.33073/pjm-2025-010pubmed: 40052212google scholar: lookup
  8. Simbu S, Orchard A, Vuuren SV. Essential Oil Compounds in Combination with Conventional Antibiotics for Dermatology. Molecules 2024 Mar 8;29(6).
    doi: 10.3390/molecules29061225pubmed: 38542862google scholar: lookup
  9. Castelo-Branco D, Lockhart SR, Chen YC, Santos DA, Hagen F, Hawkins NJ, Lavergne RA, Meis JF, Le Pape P, Rocha MFG, Sidrim JJC, Arendrup M, Morio F. Collateral consequences of agricultural fungicides on pathogenic yeasts: A One Health perspective to tackle azole resistance. Mycoses 2022 Mar;65(3):303-311.
    doi: 10.1111/myc.13404pubmed: 34821412google scholar: lookup
Subscribe to our newsletter
Join 99,357 horse owners like you who receive our email updates on horse health and nutrition.