The synthesis and applications of nanomaterials are an excitingand emerging field of scientific research. In this paper, silver nanoparticles (AgNPs) were synthesized using parsley leaf extract via the screening method (autoclave hydrothermal heating, and heater), and their microbial activities were studied. An extract of chopped parsley leaves was prepared. AgNO3 salt with a concentration of 1 mM was used. In every two methods of autoclave hydrothermal heating and heater, 5 mL of the Parsley leaf extract was mixed with 25 mL of silver nitrate salt. By FTIR analysis, the presence of Petroselinum crispum (parsley) leaf extract in NPs was identified. By using a hydrothermal autoclave and heater to synthesize AgNPs at the lowest wavelength, the size of NPs was achieved at 403 nm and 414 nm, respectively. All samples synthesized by different techniques had suitable zeta potential and acceptable stability. By giving the zeta potential of NPs synthesized by autoclave (-14.3 mV), results showed that this method is suitable for the production of AgNPs. Comparing the antibacterial attributes of the synthesized Ag NPs by different techniques (autoclave and heater) on Gram-negative bacteria (E. coli) showed 16±1, and 12±1, respectively.
