Antifungal Effect of Nano-Zno against Aspergillus species
Antifungal Effect of Nano-Zno against Aspergillus species
Aysa Khormali,1Ensieh Lotfali,2,*
1. Department of Developmental Biology, University of Science and Culture, Tehran, Iran 2. Department of Medical Parasitology and Mycology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
Introduction: Zinc is a barely active element and a strong reducing agent; due to reduction, it can oxidize to form zinc oxide, which is very beneficial to prepare zinc oxide nanoparticles.(ZnO) ZnO is the most commonly used Zn nanoparticle, because of its low price and high productiveness. Many findings revealed that ZnO could be used as an antifungal agent. In this study, antifungal effects of Nano-ZnO were studied against Aspergillus species.
Methods: Eight clinical strains of Aspergillus niger and one standard strain (Asp. niger; PTCC 5154) were cultured on potato dextrose agar slants for 10 days at 25 °C. Then spores were harvested with Tween 80 (0.1%). The final spore concentration of suspension was reached 106 spore/ml. Serial dilutions of nano-ZnO were prepared and inoculated with strains and incubated at 37°C for 24 and 48 hours. Their antifungal effect was evaluated by the minimal inhibitory concentration (MIC) according to CLSI-M38-A3.
Results: The results showed antifungal activity against Asp. niger at the range of 1-8µg/ml. Higher concentrations of nano-ZnO (8µg/ml) were effective on the Aspergillus growth, resulting in 90% reduction in the optical density in SDB medium.
Conclusion: According to our results, nano-ZnO has a significant antifungal effect against Asp.niger. this study was focused on just one species of Aspergillus. Thus, more critical evaluations have to be done on various species in different dilutions of nano-ZnO.