Investigation of Green Synthesized Silver Nanoparticles Using Aqueous Leaf Extract of Artemisia Argyi for Antioxidant and Antimicrobial Potentials

Abstract

The current study employs green synthesis to acquire silver nanoparticles (AgNPs) using Artemisia argyi and appraise their antioxidant and antimicrobial potentials. AgNPs were synthesized using aqueous leaf extract of Artemisia argyi by sunlight irradiation. They were characterized using UV-visible spectrophotometer, FESEM, FTIR and XRD. The antioxidant capacity of AgNPs were evaluated using ABTS, DPPH, iron chelation, FRAP and NO radical scavenging methods. Antimicrobial activities of AgNPs were tested against Esherichia coli and Staphylococcus aureus using disc diffusion method. Descriptive statistical analysis was used to identify significant relationship between antioxidant activities of AgNPs. The synthesized AgNPs exhibited brown color light scattering and absorbed maximum wavelength of light at 450 nm. The synthesis of AgNPs was optimum at 0.01 M AgNO3. The green synthesized AgNPs were spherical in shape with size ranging from 16 nm to 32 nm. The FTIR analysis revealed the presence of proteins, phenolic and polar nitrile compounds in the AgNPs. The purified AgNPs possessed a face centered cubic structure with coexistence of silver chloride crystals. The total phenolic and flavonoid of AgNPs were found to be 77.45 mg GAE/g AgNPs and 205.29 mg GAE/g AgNPs respectively. The radical scavenging activity (EC50) showed highest activity for NO (31.33 μg/ml) followed by ABTS (128.82 μg/ml), DPPH (263.03 μg/ml) and Fe2+ (1445.44 μg/ml) with a FRAP value of 1.22 mmol Fe2+ /mg dry weight. AgNPs possessed inhibitory effect against both strains of bacteria in concentration dependent manner. This study discovered that green synthesized AgNPs using Artemisia argyi are promising sources of effective antioxidants and antimicrobial agents with a high surface area catalytic activity.