Green synthesis of iron oxide nanoparticles using Melia azedarach flowers extract and evaluation of their antimicrobial and antioxidant activities

The methanolic extract of the flowers of Melia azedarach (BFM) is rich in phenolics and flavonoids and has been reported as antioxidant and effective for the treatment of various skin infectious diseases. However, its aqueous solubility significantly hinders its efficacy, thus alternative approaches for its de-livery need to be explored. Green synthesis has been the cheapest and most effective approach for metal nanoparticles synthesis. This study reports the synthesis of iron oxide nanoparticles (INPs) using (BFM) as a stabilizing agent. The synthesized BFM extract mediated INPs (BFM-INPs) was characterized through various techniques including UV-visible spectroscopy, FT-IR (Fourier transform infrared spec-troscopy), Dynamic light scattering (DLS), and AFM (Atomic force microscopy). The antioxidant activity of the BFM extracts and BFM-INPs was performed using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'- azino-bis (3-ethylbenzothiazoline-6-sulfonic acid (ABTS) free radical scavenging assays. The synthesized BFM-INPs were found to be spherical with a size of around 231.43 +/- 5.21 nm. The antioxidant activity of BFM extract was found to be higher than BFM-INPs owing to comparative enhanced total phenolic content and total flavonoid content TFC and TPC values. The antibacterial assay was carried out on two different bacterial strains, including S. aureus and E. coli, using ceftriaxone and amoxicillin as their respec-tive standards. Results revealed a significant decrease in MIC and IC50 values for BFM-INPs than extract alone. Hence, it can be concluded that the proposed route using FeSO4 and the methanolic extract of M. azedarach is a simple, non-toxic, and eco-friendly approach for the synthesis of INPs with enhanced antibacterial potential against bacteria.(c) 2022 Published by Elsevier B.V.