Green synthesis of gold nanoparticles using Portulaca oleracea L. extract: Antibacterial, antioxidant, and phytochemical analysis

The escalating problem of antibiotic resistance warrants the investigation of innovative antimicrobial agents. Green synthesis of nano-particles with biological sources, such as plant extracts, offers an environmental friendly benign and cheap cost as alternative to traditional methods. This study looked at the production and characterization of gold nano-particles (AuNPs) utilizing aqueous and ethanol extract of Portulaca oleracea L., as well as their bioactive components, antioxidant, and antibacterial properties. P. oleracea leaves were gathered, authenticated, and extracted using water and ethanol for AuNPs synthesis. The synthesized nano-particles were characterized using UV-Vis spectroscopy, transmission electron microscopy (TEM), and energy dispersive-X-ray spectroscopy (EDX). Bioactive chemicals included in the extracts and AuNPs were identified using gas chromatography mass-spectrometry (GC-MS). The antibacterial activity of the produced AuNPs was tested against certain bacterial pathogens using agar-well diffusion and broth macrodilution methods. Antioxidant potential was determined using established in vitro assays. UV-Vis spectra confirmed AuNP production by revealing distinctive surface plasmon resonance peaks ranging from 450 to 520 nm. TEM scans revealed mainly spherical nanoparticles. EDX result validated the composition of the elements of the AuNPs, including Au. GC-MS found many bioactive chemicals present in both extracts and nanoparticles, with phytol accounting for 30.40%. AuNPs revealed substantial anti-bacterial activity against the studied bacteria pathogens, with varied inhibition levels at different doses, as well as significant antioxidant potential. This study effectively demonstrated the green production of AuNPs with P. oleracea extracts. The AuNPs showed excellent antibacterial and antioxidant characteristics, indicating that they could be used as innovative therapeutic agents for bacterial infections and oxidative stress.