Optimizing the microbial synthesis of silver nanoparticles using Gloeophyllum striatum and their antimicrobial potential evaluation

Abstract

Abstract The search for new sources of silver nanoparticles (AgNPs) is being continued. Microbial synthesis seems to be the most advantageous solution for large scale production. The use of brown rot fungi is scarcely described, but it might be a promising solution due to their known enzymatic abilities. In the present study, the synthesis of AgNPs with the use of Gloeophyllum striatum DSM 9592 was performed in various process conditions. The obtained silver nanoparticles were characterized using UV-Vis, FT-IR, SEM and NTA techniques. Antimicrobial potential of all synthesized nanoparticles was tested against various Gram-positive and Gram-negative bacteria strains. P. aeruginosa occurred to be the most sensitive with MIC value of 1.56 µg/ml. The research was extended by the biofilm formation assay for the selected strain. The haemolytic and cytotoxic activity of obtained AgNPs was also tested. It was established that the toxicity of synthesized AgNPs did not reach the LC50 level in the concentration equal to the MIC90 value against P. aeruginosa. These results highlight the possible utility of mycogenic silver nanoparticles as an antibacterial agent in antiseptics or other external treatments.