Green synthesis of silver nanoparticles from Verbena officinalis L.: Characterization and antibacterial efficacy

Field: Pharmacology, Toxicology and Pharmaceutics (Life Sciences)

In recent times, attention has been paid to phyto-assisted synthesis of nanoparticles using plant extracts due to its ecofriendly, low cost and easy modes. In our research, silver nanoparticles (AgNPs) were synthesized using methanolic root extract of Verbena officinalis L. The AgNPs were tested for antibacterial activity against Escherichia coli ATCC-O157 H: 7 and Staphylococcus aureus ATCC-25923 using the disc diffusion method and minimum inhibitory concentration (MIC) determination. The AgNPs formation was initially observed by the color change and further verified using UV-Vis spectrophotometer, Fourier Transform Infra-red (FT-IR) and X- Ray crystallography (XRD). The color change from yellow to brown in the reaction mixture was an indication for the synthesis of AgNPs. Further confirmation was established 434 nm in UV-Vis spectroscopy. The FTIR analysis displayed bands analogous to functional groups of plant’s phytochemicals that were accountable for reducing and capping of AgNPs. The AgNPs analysis by XRD validated the crystallinity of AgNPs at 2? angles of 38.000, 44.160, 64.400, and 77.330 harmonizing to planes at (111), (200), (220), and (311), respectively and established their average size (22.67 nm). The AgNPs exhibited strong antibacterial potential against the tested pathogenic bacteria. The AgNPs exhibited significantly (p<0.001) better antibacterial effect against S. aureus than E. coli. The smallest MIC of 10.42 µg/mL was observed against S. aureus. These outcomes apparently demonstrated the efficacy of the components of the V. officinalis root extract in the significant enrichment of the toxicity of the AgNPs against the bacterial pathogens.In recent times, attention has been paid to the green synthesis of nanoparticles using plant extracts due to their eco-friendly, low-cost and easy modes. In the present research, silver nanoparticles (AgNPs) were synthesized using methanolic root extract of Verbena officinalis L. The AgNPs were tested for antibacterial activity against Escherichia coli ATCC-O157 H: 7 and Staphylococcus aureus ATCC-25923 using the disc diffusion method and minimum inhibitory concentration (MIC) determination. The AgNPs formation was initially observed by the color change and further verified using UV-Vis spectrophotometer, Fourier Transform Infra-red (FT-IR) and X-Ray crystallography (XRD). The color change from yellow to brown in the reaction mixture was an indication of the synthesis of AgNPs. Further confirmation was established at 434 nm in UV-Vis spectroscopy. The FTIR analysis displayed bands analogous to functional groups of the plant’s phytochemicals that were accountable for reducing and capping of AgNPs. The AgNPs analysis by XRD validated the crystallinity of AgNPs at 2? angles of 38.00°, 44.16°, 64.40° and 77.33° harmonizing to planes at (111), (200), (220) and (311), respectively and established their average size (22.67 nm). The AgNPs exhibited strong antibacterial potential against the tested pathogenic bacteria. The AgNPs exhibited significantly (p<0.001) better antibacterial effect against S. aureus than E. coli. The smallest MIC of 10.42 ?g/mL was observed against S. aureus. These outcomes demonstrated the efficacy of components of the V. officinalis root extract in the significant enrichment of the toxicity of the AgNPs against the bacterial pathogens.