Antibacterial potentials of silver nanoparticles synthesized from Calopogonium mucunoides leaves extract on some enteric bacteria

Abstract

Silver nanoparticles (AgNPs) synthesized from Calopogonium mucunoides aqueous leaf
extract and determination of the antibacterial activities against selected enteric bacte-
ria were conducted in this study. The AgNPs were produced in an eco-friendly manner
by combining a 1 mM silver nitrate solution with an aqueous C. mucunoides leaf extract
under direct sunshine. UV-visible spectrophotometry, dynamic light scattering (DLS), and
high-resolution transmission electron microscopy (HRTEM) were utilized to study the
AgNPs (HRTEM). AgNPs were brown in colour and had a UV-Vis absorbance peak at
441– 445 nm. DLS uncovered monodispersed AgNPs with an 80.77 nm hydrodynamic
diame- ter. A HRTEM image revealed that AgNPs with an average size of 7.5 nm had a
spherical morphology. The antimicrobial susceptibility of colloidal AgNPs (50, 75, 100,
and 150 μg/ mL) utilizing agar diffusion techniques against bacterial isolates
(Pseudomonas aeruginosa strain DM1, Salmonella typhi strain T8, and Escherichia coli
Acj 213) revealed inhibition zones ranging from 16.70 to 21.00 mm. For three bacterial
isolates, the lowest inhibitory con- centrations were 37.50, 37.50, and 9.38 μg/mL, and
the minimum bactericidal values were 75, 75, and 37.5 μg/mL, respectively. The
outcomes of this study indicate that the aqueous leaf extract of C. mucunoides can be
used to synthesize AgNPs with a considerable anti- bacterial impact against clinical
isolates of P. aeruginosa strain DM1, S. typhi strain T8, and E. coli Acj 213. To assure
the safety of biogenic AgNPs for the development of novel antimicrobial drugs,
additional research is needed to assess their toxicity.