Biosynthesis and characterization of silver nanoparticles from Punica granatum (pomegranate) peel waste and its application to inhibit foodborne pathogens

Abstract

Despite their role in controlling pathogens, the misuse of antibiotics leads to the antibiotic resistance phenomenon. The biosynthesis process of silver nanoparticles from plant extracts has earned wide regard worldwide because of its eco-friendly characteristics. The current study aims to biosynthesize and characterize silver nanoparticles from pomegranate peel waste PPW-AgNPs as well as test their antimicrobial potentials against foodborne pathogens. Ultraviolet (UV) spectrum, X-ray diffraction analysis (XRD), Zeta potential, Fourier transform infrared (FTIR) and scanning electron microscopy (SEM) analysis were used to characterize the produced PPW-AgNPs. The colour change from yellow to brown, the detection of a peak in a UV spectrum at 440 nm of 0.9 SPR, and four intense peaks in XRD and SEM analysis revealed the existence of spherical particles of PPW-AgNPs. Zeta potential was − 0.03 revealing the negative charge of PPW-AgNPs. Eight foodborne pathogenic strains (6 bacteria and 2 fungal strains) Bacillus subtilis ATCC 6633, Enterococcus faecalis ATCC 29212, Escherichia coli ATCC 8379, Klebsiella pneumoniae ATCC 00607, Salmonella typhi DSM 17058, Shigella sonnei DSM 5570, Aspergillus flavus ATCC 9643, and Rhizopus oryzae ATCC 96382 were used to test the inhibitory potential of PPW-AgNPs. All silver nanoparticles exhibited high antimicrobial activity against all tested strains. The most sensitive strain was B. subtilis while the highest resistant one was R. oryzae with IZD of 4.5 and 0.96cm. Pomegranate peel waste plays a key role in the simple, eco-friendly green synthesis of extracellular stable AgNPs as an alternative source for harmful chemical disinfectants.