ISSN print edition: 0366-6352
ISSN electronic edition: 1336-9075
Registr. No.: MK SR 9/7
Biogenic synthesis, antioxidant and antimicrobial activity of silver and manganese dioxide nanoparticles using Cussonia zuluensis Strey
Nomfundo T. Mahlangeni, Judie Magura, Roshila Moodley, Himansu Baijnath, and Hafizah Chenia
School of Chemistry and Physics, University of KwaZulu-Natal, Durban, South Africa
Received: 24 January 2020 Accepted: 4 June 2020
Synthesis of nanoparticles using naturally occurring biomolecules has become the preferred method due to increased concerns over environmental degradation. In this study, the biosynthesis of manganese dioxide nanoparticles (MnO2NPs) and silver nanoparticles (AgNPs) using extracts and the biomolecule, aralia cerebroside, isolated from the medicinal plant species, Cussonia zuluensis Strey, was investigated. The size and morphology of nanoparticles observed using microscopic techniques indicated an average particle size of 7.43 nm (spherical and polydispersed) for AgNPs and a layer of thin film surrounding the particles, confirming the capping by biomolecules. AgNPs exhibited better antibacterial activity than MnO2NPs and were most active against Escherichia coli and Enterococcus faecalis. MnO2NPs presented as ultrathin nanoflakes with grainy morphology ranging from 11 to 29 nm when capped with biomolecules from the extract, and presented as nanospheres surrounded by nanosheets ranging from 6.99 to 16.57 nm when capped with aralia cerebroside. The radical scavenging activity was found to be MnO2NPs (extract) > MnO2NPs (cerebroside) > AgNPs (extract) > extract > cerebroside, and the ferric reducing antioxidant power was found to be cerebroside > extract > MnO2NPs (cerebroside) > MnO2NPs (extract) > AgNPs (extract). MnO2NPs exhibited better antioxidant activity than AgNPs with size and morphology of nanoparticles being influenced by the capping agent, which, in turn, influenced antioxidant activity as seen with MnO2NPs. This study confirms the significance of the metal or metal oxide core and capping biomolecules for targeted therapeutic activity of nanoparticles using the plant-mediated synthesis route.
Keywords: Aralia cerebroside; Silver nanoparticles; Radical scavenging activity; Escherichia coli; Enterococcus faecalis
Full paper is available at www.springerlink.com.
Chemical Papers 74 (12) 4253–4265 (2020)
Friday, September 17, 2021