Biosynthetic potential assessment of four food pathogenic bacteria in hydrothermally silver nanoparticles fabrication

Abstract

Silver nanoparticles (Ag NPs) were synthesized using four pathogenic bacterial extracts namely, Bacillus cereus, E. coli, Staphylococcus aureus and Salmonella entericasubsp.enterica. Synthesis process were hydrothermally accelerated using temperature, pressure and heating time of 121°C, 1.5 bar ad 15 min. Physico- chemical characteristics of the fabricated Ag NPs, including, particle size, polydispersity index (PDI), zeta potential, broad emission peak (λmax) and concentration were evaluated using UV-Vis spectrophotometer and dynamic light scattering (DLS) particle size analyzer. Furthermore, main existed functional groups in the provided bacterial extracts were recognized using Fourier transform infrared spectroscopy. The obtained results revealed that two main peaks were detected around 3453 and 1636.5 cm-1, for all bacterial extracts, were interrelated to the stretching vibrations of hydroxyl and amide groups which those had key roles in the reduction of ions and stabilizing of the formed Ag NPs. The results also indicated that, Ag NPs with much desirable characteristics, including minimum particle size (25.62 nm) and PDI (0.381), and maximum zeta potential (-29.5 mV) were synthesized using S. e. subsp. enterica extract. λmax, absorbance and concentration values for the fabricated Ag NPs with this bacterial extract were 400 nm, 0.202% a.u. and 5.87 ppm.

Keywords

• silver nanoparticles
• biosynthesis
• pathogens
• bacteria strains
• physico-chemical properties