Antifungal Activity of Biologically Synthesized Metallic Nanoparticles from Streptomyces species SS7

Background: One area of nanotechnology that has transformed the biological sciences is green manufacturing of nanoparticles. Objectives: This work aims to report the antifungal activities of selenium (Se) and silver (Ag) nanoparticles (NPs) from Streptomyces SS7 using an environmentally safe technique. Methodology: Identification of Streptomyces SS7 using 16S rRNA sequence analysis was done and synthesis of Se and AgNPs was examined by ultraviolet–visible spectroscopy, transmission electron microscopy (TEM), and dynamic light scattering (DLS). The antifungal activity of NPs against Candida albicans and Aspergillus fumigatus was assessed. Results: Based on 16S rRNA sequence, Streptomyces SS7 was linked to Streptomyces sporocinereus, Streptomyces hygroscopicus, Streptomyces endus and Streptomyces demainii. Absorption bands of Se and AgNPs were obtained around 230 and 250 nm. TEM showed spherical particles with size range from 11-24 nm. SeNPs measured 2.93 and 101.8 nm in size, while AgNPs measured 9.432 nm using DLS. MICs of AgNPs were 1.25 mg/mL against Candida and less than 0.075 mg/mL against Aspergillus fumigatus. Candida albicans and Aspergillus fumigatus had MICs of 2.5 mg/mL for SeNPs except for Candida albicans C12 and Candida albicans CA, were 1.25 and 5 mg/mL. Conclusion: this study demonstrated the fungistatic activity of Se and AgNPs with a higher potency of AgNPs.