Synthesis of Tellurium Nanoparticles Using Moringa oleifera Extract, and Their Antibacterial and Antibiofilm Effects against Bacterial Pathogens

Today, pathogenic microorganisms are increasingly developing resistance to conventional drugs, necessitating the exploration of alternative strategies. In addressing this challenge, nano-based antibacterial agents offer a promising avenue of research. In the present study, we used an extract ofMoringa oleifera, a widely recognized edible and medicinal plant, to synthesize biogenetic tellurium nanoparticles (Bio-TeNPs). Transmission electron microscopy, scanning electron microscopy, and dynamic light scattering analyses revealed that the obtained Bio-TeNPs had diameters between 20 and 50 nm, and zeta potential values of 23.7 ± 3.3 mV. Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy revealed that the Bio-TeNPs consisted primarily of Te(0), along with some organic constituents. Remarkably, these Bio-TeNPs exhibited potent antibacterial activity against a spectrum of pathogens, includingEscherichia coli,Klebsiella pneumoniae,Shigella dysenteriae,Salmonella typhimurium,Streptococcus pneumoniae, andStreptococcus agalactiae. In addition, findings from growth curve experiments, live/dead cell staining, and scanning electron microscopy observations of cell morphology demonstrated that Bio-TeNPs at a concentration of 0.07 mg/mL effectively disruptedE.coliandK.pneumoniaecells, leading to cell rupture or shrinkage. The biofilm inhibition rates of 0.7 mg/mL Bio-TeNPs againstE.coliandK.pneumoniaereached 92% and 90%, respectively. In addition, 7 mg/mL Bio-TeNPs effectively eradicatedE.colifrom the surfaces of glass slides, with a 100% clearance rate. These outcomes underscore the exceptional antibacterial efficacy of Bio-TeNPs and highlight their potential as promising nanomaterials for combating bacterial infections.