title: In vitro antifungal activity of silver nanoparticles against ocular pathogenic filamentous fungi.
abstract: OBJECTIVE
  Fungal keratitis is emerging as a major cause of vision loss in a developing country such as China because of higher incidence and the unavailability of effective antifungals. It is urgent to explore broad-spectrum antifungals to effectively suppress ocular fungal pathogens, and to develop new antifungal eye drops to combat this vision-threatening infection. The aim of this study is to investigate the antifungal activity of silver nanoparticles (nano-Ag) in comparison with that of natamycin against ocular pathogenic filamentous fungi in vitro.
  
  
  METHODS
  Susceptibility tests were performed against 216 strains of fungi isolated from patients with fungal keratitis from the Henan Eye Institute in China by broth dilution antifungal susceptibility test of filamentous fungi approved by the Clinical and Laboratory Standards Institute M38-A document. The isolates included 112 Fusarium isolates (82 Fusarium solani species complex, 20 Fusarium verticillioides species complex, and 10 Fusarium oxysporum species complex), 94 Aspergillus isolates (61 Aspergillus flavus species complex, 11 Aspergillus fumigatus species complex, 12 Aspergillus versicolor species complex, and 10 Aspergillus niger species complex), and 10 Alternaria alternata isolates. The minimum inhibitory concentration (MIC) range and mode, the MIC for 50% of the strains tested (MIC50 value), and the MIC90 value were provided for the isolates with the SPSS statistical package.
  
  
  RESULTS
  MIC50 value of nano-Ag were 1, 0.5, and 0.5 μg/mL for Fusarium spp., Aspergillus spp., and Al. alternata, respectively. MIC90 values of nano-Ag were 1, 1, and 1 μg/mL for Fusarium spp., Aspergillus spp., and Al. alternata, respectively. MIC50 values of natamycin were 4, 32, and 4 μg/mL for Fusarium spp., Aspergillus spp., and Al. alternata, respectively. MIC90 values of natamycin were 8, 32, and 4 μg/mL for Fusarium spp., Aspergillus spp., and Al. alternata, respectively.
  
  
  CONCLUSIONS
  Nano-Ag, relative to natamycin, exhibits potent in vitro activity against ocular pathogenic filamentous fungi.
authors: Laboratory of Ocular Pharmacology, Henan Eye Institute, Henan Eye Hospital, Zhengzhou, China. xuyan990301@yahoo.com.cn
authors: Yan
authors: Y
authors: Xu
authors: Chuanwen
authors: C
authors: Gao
authors: Xiaohua
authors: X
authors: Li
authors: Yi
authors: Y
authors: He
authors: Lutan
authors: L
authors: Zhou
authors: Guangren
authors: G
authors: Pang
authors: Shengtao
authors: S
authors: Sun
mesh_terms: D000935:Antifungal Agents / Q000494:pharmacology / Q000627:therapeutic use*; D015821:Eye Infections, Fungal / Q000188:drug therapy*; D005658:Fungi / Q000187:drug effects* / Q000302:isolation & purification; D006801:Humans; D008826:Microbial Sensitivity Tests / Q000379:methods; D053758:Nanoparticles / Q000008:administration & dosage / Q000627:therapeutic use*; D012834:Silver / Q000494:pharmacology / Q000627:therapeutic use*
chemical_list: D000935:Antifungal Agents; D012834:Silver