The effect of silver nanoparticles and nystatin on mixed biofilms of Candida glabrata and Candida albicans on acrylic.
The aim of this study was to compare biofilm formation by Candida glabrata and Candida albicans on acrylic, either individually or when combined (single and dual species) and then examine the antimicrobial effects of silver nanoparticles and nystatin on these biofilms. Candidal adhesion and biofilm assays were performed on acrylic surface in the presence of artificial saliva (AS) for 2 h and 48 h, respectively. Candida glabrata and C. albicans adherence was determined by the number of colony forming units (CFUs) recovered from the biofilms on CHROMagar(®) Candida. In addition, crystal violet (CV) staining was used as an indicator of biofilm biomass and to quantify biofilm formation ability. Pre-formed biofilms were treated either with silver nanoparticles or nystatin and the effect of these agents on the biofilms was evaluated after 24 h. Results showed that both species adhered to and formed biofilms on acrylic surfaces. A significantly (P < 0.05) higher number of CFUs was evident in C. glabrata biofilms compared with those formed by C. albicans. Comparing single and dual species biofilms, equivalent CFU numbers were evident for the individual species. Both silver nanoparticles and nystatin reduced biofilm biomass and the CFUs of single and dual species biofilms (P < 0.05). Silver nanoparticles had a significantly (P < 0.05) greater effect on reducing C. glabrata biofilm biomass compared with C. albicans. Similarly, nystatin was more effective in reducing the number of CFUs of dual species biofilms compared with those of single species (P < 0.05). In summary, C. glabrata and C. albicans can co-exist in biofilms without apparent antagonism, and both silver nanoparticles and nystatin exhibit inhibitory effects on biofilms of these species.
IBB-Institute for Biotechnology and Bioengineering, Centre of Biological Engineering, University of Minho, Braga, Portugal.
Sónia
S
Silva
Priscila
P
Pires
Douglas R
DR
Monteiro
Melyssa
M
Negri
Luiz F
LF
Gorup
Emerson R
ER
Camargo
Débora B
DB
Barbosa
Rosário
R
Oliveira
David W
DW
Williams
Mariana
M
Henriques
Joana
J
Azeredo
D000180:Acrylic Resins; D000268:Adhesiveness / Q000187:drug effects; D000935:Antifungal Agents / Q000494:pharmacology*; D018441:Biofilms / Q000187:drug effects* / Q000254:growth & development; D018533:Biomass; D002176:Candida albicans / Q000187:drug effects* / Q000502:physiology; D041221:Candida glabrata / Q000187:drug effects* / Q000502:physiology; D015169:Colony Count, Microbial; D008855:Microscopy, Electron, Scanning; D053758:Nanoparticles; D009761:Nystatin / Q000494:pharmacology*; D012834:Silver / Q000494:pharmacology*
D000180:Acrylic Resins; D000935:Antifungal Agents; D009761:Nystatin; D012834:Silver