Antimicrobial activity and toxicological risk assessment of silver nanoparticles synthesized using an eco-friendly...

Recently, nanomaterials synthesized ecologically using microorganisms have attracted much interest. In the present study, the ability of Gloeophyllum striatum to synthesize silver nanoparticles is described for the first time. Nanoparticles were formed in an eco-friendly extracellular manner and characterized by UV-Vis, FT-IR, MADLS and SEM techniques. The obtained nanoparticles showed excellent activity against gram-positive and gram-negative bacteria. The MIC values for gram-negative bacteria were 15 µM, while for gram-positive strains they reached 30 µM. The haemolytic and cytotoxic activities of the synthesized nanoparticles towards mammalian cells were also determined. The addition of AgNPs at the concentrations above 30 µM caused 50% haemolysis of red blood cells after they 24-hour incubation. A decrease in the viability of fibroblasts by over 50% was also found in the samples treated with nanoparticles at the concentrations above 30 µM. The ecotoxicological risk of silver nanoparticles was assessed using A. franciscana and D. magna crustaceans as well as L. sativum plants. The EC₅₀ values for A. franciscana and D. magna were 61.97 and 0.275 µM, respectively. An about 20% reduction in the length of L. sativum shoots and roots was noted after the treatment with AgNPs at the concentration of 100 µM.