The synergistic effect of biosynthesized silver nanoparticles from a combined extract of Petroselinum crispum and Piper betle: in vitro antibacterial activity

Green synthesis of silver nanoparticles from the combination of Petroselinum crispum and Piper betle was confirmed by an absorption peak at 410 nm. Fourier transform infrared spectroscopy analysis showed the existence of multiple possible functional groups through C O, N H and O H stretching. The presence of several elements along with silver has been found by Energy-dispersive X-ray spectroscopy, while a high-intensity reflection peak at 38.1 ° revealed information regarding the crystalline nature of synthesized nanoparticles. Additionally, scanning electron microscopy (SEM) and dynamic light scattering (DLS) analyses were performed to investigate the structural and morphological characteristics of the as-prepared AgNPs.. The antibacterial activity of aqueous, ethanol, and butanol extracts was evaluated using the agar well diffusion method. Results indicated enhanced antimicrobial efficacy of the phyto-synthesized AgNPs against both Gram-positive ( Staphylococcus aureus ) and Gram-negative ( Escherichia coli and Salmonella Typhimurium ) bacteria. Additionally, the combined plant extracts demonstrated greater antibacterial activity than individual extracts, further supporting the significance of plant synergy. Among the different solvent systems, AgNPs synthesized using butanol extracts exhibited the highest antibacterial activity, showing a maximum zone of inhibition (29 mm) against Salmonella Typhimurium . The minimum inhibitory concentrations (MICs) of the plant extracts, determined using the microdilution method, ranged from 0.0098 to 2.5 mg/mL, depending on the bacterial strain and extract type. This study demonstrates an eco-friendly synthesis of silver nanoparticles using a combined extract of Petroselinum crispum and Piper betle , enhancing their antibacterial efficiency. The synergistic interaction between the plant extracts and AgNPs presents a promising strategy to counteract bacterial resistance.