Biosynthesis of metallic nanoparticles from waste Passiflora edulis peels for their antibacterial effect and catalytic activity

Abstract

Recently, the waste agricultural materials have been widely considerable for green synthesis of noble metallic nanoparticles (MNPs) due to cost efficiency and environmental protection. This study has presented a simple method for the preparation of silver nanoparticles (AgNPs) and gold nanoparticles (AuNPs) utilizing aqueous extract of waste Passiflora edulis peel (PEP) as reducing and stabilizing agents. The formation of MNPs was optimized reaction conditions to obtain the best colloidal solutions. The characterizations of the biosynthesized MNPs were performed by analysis techniques such as Fourier transmission infrared spectroscopy (FTIR), X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED). The TEM data confirmed PEP-AgNPs and PEP-AuNPs in the spherical shape with mean size of 25 nm and 7 nm, respectively. The XRD and SAED patterns showed the synthesized nanoparticles existing in crystalline nature. Antibacterial and catalytic activities have been investigated for their applications. The PEP-AgNPs exhibited a strong antibacterial activity against three strains including Escherichia coli, Bacillus subtilis, and Staphylococcus aureus. The excellently catalytic activity of both the biosynthesized nanoparticles has been demonstrated for reduction of nitrophenols and degradation of toxic organic dyes via study on their kinetics.