Antifungal activity of green synthesized curcumin-coated silvernanoparticles alone and in combination with antifungal drugs

Background and Aim : Candida and Aspergillus species are the causative agents of a wide rangeof infections in immunocompetent and immunocompromised individuals. Drug resistance hasbeen reported with an increasing trend during the past decades among these fungi. Accordingly,searching for alternative approaches seems necessary. Using nanomaterials alone or incombination with antifungal drugs is a promising approach. The aim of this study was toinvestigate the the antifungal activity of curcumin-coated silver nanoparticles alone and incombination with antifungal drugs against a set of pathogenic Candida and Aspergillus species.Methods : A set of ۳۰ fungal isolates including A. fumigatus (n=۶), A. flavus (n=۶), C. albicans(n=۶), C. parapsilosis (n=۶), and C. krusei (n=۶) were included in this study. The susceptibilitypattern of all isolates to fluconazole and itraconazole was evaluated as per CLSI method.Curcumin-coated silver nanoparticles were synthesized and their characteristics were determined.The antifungal activity of curcumin-coated silver nanoparticles was tested alone and incombination with antifungal drugs. Finally, TEM analysis was performed to determine the effectof nanoparticles on a selected strain.Results : Based on the results of UV–Vis spectroscopy, the nanoparticles were synthesizedsuccessfully with a mean ± SD size of ۲۹.۱ ± ۵.۶ nm and spherical shape. Results of antifungalsusceptibility testing revealed that the majority of yeasts (۱۵/۱۸, ۸۳.۳۳%) were fluconazoleresistant.Resistance to itraconazole was also noted for ۴ and ۷ Candida and Aspergillus strains,respectively. Curcumin-coated silver nanoparticles demonstrated promising antifungal activity,especially against Candida species with geometric mean minimum inhibitory and fungicidalconcentrations much lower than fluconazole against all the studied fungi. These values were alsolower than those of itraconazole in some instances, i.e. against C. albicans and A. fumigatus. Invitro combination of curcumin-coated silver nanoparticles resulted in synergistic and indifferentinteractions against Candida and Aspergillus species, respectively. TEM analysis revealed that thenanoparticle result in defects in cell wall and cell membrane of Candida.Conclusion : Curcumin-coated silver nanoparticles, either alone or in combination with antifungaldrugs, have good inhibitory effects on Candida species. Accordingly, further studies for theirapplication against other fungi and even in murine models of infection would be beneficial.

کلیدواژه ها:

Curcumin ، silver nanoparticle ، drug resistance ، drug combination