Green synthesized silver nanoparticles demonstrating enhanced in vitro and in vivo antibiofilm activity against Candida spp.

Abstract

Candida species are opportunistic fungal pathogens, which are known for their biofilm associated infections on implanted medical devices in clinical settings. Broad spectrum usage of azole groups and other antifungal agents leads to the occurrence of drug resistance among Candida species. Most of the antifungal agents have failed to treat the biofilm mediated Candida infections. In the present study, silver nanoparticles (AgNPs) were synthesized using Dodonaea viscosa and Hyptis suoveolens methanolic leaf extracts and characterized by ultraviolet-visible absorption spectroscopy, X-ray diffraction analysis, Fourier transform infrared spectroscopy and Scanning electron microscopy, Dynamic light scattering, and Zeta potential analysis. The main goal of this study was to assess the AgNPs for their antibiofilm efficacy against Candida spp. through microscopic analysis and in vitro virulence assays. The results revealed that AgNPs strongly inhibited more than 80% biofilm formed by Candida spp. Furthermore, the AgNPs also reduced the yeast-to-hyphal transition, exopolysaccharide biosynthesis, secreted aspartyl proteinase production which are the major virulence factors of Candida species. This study reveals that biosynthesized AgNPs can be considered for the treatment of biofilm related Candida infections.

Silver nanoantibiotics display strong antifungal activity against the emergent multidrug-resistant yeastCandida aurisunder both planktonic and biofilm growing conditions

“…We note that the AgNPs IC50 value for the C. auris AR #0390 strain is higher than the value reported for the same strain as reported by Lara et al (1.1 μg mL -1 vs 0.06 μg mL -1 , respectively), which is most likely related to the different techniques used for the synthesis of these nanoantibiotics resulting in AgNPs with different characteristics. Also, the antibiofilm activity of our AgNPs is comparable to the activity described for AgNPs synthesized using different methods against other Candida species [29,34,35].…”

<p>Anticandidal activity of biosynthesized silver nanoparticles: effect on growth, cell morphology, and key virulence attributes of Candida species</p>

“…from 79 to 88% at 10 µg/mL. 52 Monteiro et al 53 reported that colloidal suspensions of AgNPs at 54 μg/mL inhibit the biofilm formation approximately 54 and 90% in C. albicans and C. glabrata, respectively. The exact mechanism of inhibition of biofilm formation by AgNPs is not known.…”

“…However, cells treated with ScAgNPs not only inhibit the production of exopolysaccharides, but also inhibit the growth of cells ( Figure S1). Muthamil et al 52 reported that AgNPs strongly inhibit the EPS production in C. albicans, C. glabrata,and C. tropicalis. The visualization and quantification of biofilm and distribution of live and dead cells after treatment of ScAgNPs were evaluated by CLSM using LIVE/DEAD biofilm viability florescent stains, ie, ConA-FITC and PI.…”

Green synthesis of polysaccharide-based inorganic nanoparticles and biomedical aspects

“…AgNPs can also impart their antibacterial activity through the interaction and interruption of the macromolecules function such as DNA and enzyme by mechanism such as a free-radical production or electron release. AgNPs produced using the EPS secreted from B. subtilis has shown an effective inhibition against bacterial growth, with greater efficiency toward gram-negative than grampositive bacteria [61]. These types of AgNPs synthesized from bacteria secreted ESP have shown successful inhibition activity against microorganisms such as P. aeruginosa, S. aureus, B. cereus, E. coli, and P. vulgaris [62,63].…”