Biological synthesis of Ag-nanoparticles using Stachys parviflora and its inhibitory potential against Xanthomonas campestris

Biologically synthesized silver nanoparticles are considered comparatively more effective, eco-friendly and non-hazardous than current physicochemically synthesized nanoparticles. Among several other approaches, green plants have been observed to be comparatively more proficient in the synthesis of nanomaterials. This study focuses on the green synthesis of silver nanoparticles using plant extract of Stachys parviflora (SpAgNPs). The experimental plant was also tested for its qualitative and quantitative phytochemicals, its antioxidant potential through DPPH activity and high performance liquid chromatography (HPLC).The synthesis of Sp-AgNPs was confirmed by using UV-visible spectroscopy, fourier transform infrared spectroscopy (FTIR), energy dispersive x-ray (EDX), X-ray diffraction (XRD), scanning and transmission electron microscopy, thermogravimetric analysis (TGA) and gas chromatography-mass spectrometry (GCMS-). The plant extract of S. parviflora was found sustaining a highest DPPH scavenging activity (88.64%) and owning roughly 23 potential bioactive compounds. The FTIR analysis revealed the presence of important functional groups and XRD pattern indicated the formation of spherical crystal, while, EDX confirmed the presence of Ag and other elements in Sp-AgNPs. The spherical morphological shape of the nanoparticle with size below 100 nm range was confirmed through SEM and TEM while, its stability was verified by TGA. The in-vitro and in-planta antibacterial activities of the particles against Xanthomonas campestris showed maximum inhibition by uncentrifuged silver nanoparticles in combination with S. parviflora plant extracts (Sp-AgNPs+PE) followed by centrifuged nanoparticles (Sp-AgNPs) and plants extract alone (PE). These findings suggest that biosynthesized Sp-AgNPs can be used to control X. campestris effectively. (c) 2023 SAAB. Published by Elsevier B.V. All rights reserved.