Green synthesis of Stereospermum suaveolens capped silver and gold nanoparticles and assessment of their innate antioxidant, antimicrobial and antiproliferative activities

Abstract

Plant-extract mediated nanoparticles synthesis is a viable alternative to chemical reduction techniques. Here, we report the microwave-assisted rapid synthesis of silver and gold nanoparticles by the phytoreducer Stereospermum suaveolens for the first time. The formation of the nascent silver and gold nanoparticles is confirmed by their intense surface plasmon resonance peaks at 431 and 585 nm in UV-visible spectroscopy. The poly phenolic and alcoholic functional groups present in the aqueous root bark extract that performed the bioreduction processes have been detected using Fourier transform infrared spectroscopy. Powder X-ray diffraction and selected area electron diffraction patterns settled face centered cubic crystal structures to both silver and gold nanoparticles with a preferred orientation towards the (111) plane. Transmission electron microscopic analysis proved more or less spherical geometry of the silver and gold nanoparticles with average diameter of 49.77 ± 11.64 and 27.19 ± 5.96 nm, respectively. The nanoparticles showed excellent free-radical scavenging activity than the root bark extract Stereospermum suaveolens and the IC values obtained were 108.36 ± 1.62, 45.59 ± 0.18, 34.53 ± 0.31 µg/mL, respectively, for the extract, gold and silver nanoparticles. The metal nanoparticles have accomplished good antimicrobial properties towards bacterial and fungal pathogens and were demonstrated herein. The antiproliferative effects of the synthesized silver and gold nanoparticles on human lung adenocarcinoma cells A549 were studied using the MTT assay and the obtained IC values 33.81 ± 0.72 and 52.97 ± 0.73 µg/mL lies in the clinical range.

Biosynthesis of Silver and Gold Nanoparticles Using Aqueous Extract from Crinum latifolium Leaf and Their Applications Forward Antibacterial Effect and Wastewater Treatment

“…The TEM images suggest that AgNPs are mostly spherical in shape with a mean diameter of 20.5 nm while the morphology of AuNPs is found to be multishaped including spherical, triangular, and octagonal shapes in an average size of 17.6 nm. Differences in size and shape between the MNPs can relate to differences in the reduction potentials and phytochemicals of stabilized agents of MNPs [32][33][34][35][36]. The HR-TEM images of the single nanoparticles showed clear crystal lattice of MNPs.…”

Green Synthesis of Metallic Nano-Particles and Their Potential in Bio-Medical Applications

“…Biogenic synthesis of metallic nanoparticles gains significance importance due to its eco-friendliness and easiness. Green synthesis of gold nanoparticles by plants such as Musa acuminatacolla, Euphrasia officinalis, Stereospermum suaveolens, Clitoria Ternatea has been reported [28][29][30][31]. The potential of bacteria, cyanobacteria, and fungi for nanoparticle synthesis also reported in various researches [32][33][34][35][36][37].…”

Synthesis, characterization and functional evaluation of gold nanoparticles prepared using Dovyalis abyssinica leaf extracts as reducing and surface capping agent

“…The radical scavenging assay of the synthesized Au NPs was performed using DPPH radical following previous procedures (Francis et al, 2018;Patil et al, 2019) with slight modification. Both the D. abissinica leaf extract and Au NPs were examined separately to study the chemical nature of bioactive compounds extracted from the plant and the synthesized Au NPs capped with extracted molecules.…”