Biosynthesis of ZnO nanoparticles using green tea extract and determination of its antibiofilm effect on Pseudomonas aeruginosa strains isolated from wound infection

Owing to the antimicrobial activity of ZnO nanoparticles without causing resistance, such substances could be considered as an appropriate alternative to prevent bacterial biofilm formation. The aim of this study was to the biosynthesis of ZnO nanoparticles using green tea extract and determination of its effect on biofilm formation in Pseudomonas aeruginosa isolates separated from wound infection.   In this cross-sectional study, biosynthetic nanoparticles were evaluated by X-ray diffraction, energy dispersive X-ray analysis, scanning electron microscopy and transmission electron microscopy. Determination of antimicrobial activity and minimum inhibitory concentration of nanoparticles were done by micro broth dilution method. The antibiofilm activity was investigated using biofilm formation by O'Toole 2011 method.   The biosynthesis of nanoparticles was confirmed by analysis. The size of the nanoparticles was determined in the range of 10 to 90 with an average of less than 40 nm. The nanoparticles had anti-microbial activities in concentrations of 250, 500 and 1000 ug/mL and minimum inhibitory concentration of 500 ug/mL was reported. The antimicrobial and antibiofilm effects of the nanoparticles rose with increasing the concentrations.   The biosynthesis of nanoparticles with the extract has a variety of benefits such as simplicity, good stability, without energy consumption, less time-consuming, non-toxic wastes, economical efficiency, and large scale synthesis capability. According to the antimicrobial and antibiofilm properties, the use of these nanoparticles as coatings in medical equipment and food industries is recommended.