Biological Synthesis of Silver Nanoparticles by Amaryllis vittata (L.) Herit: From Antimicrobial to Biomedical Applications

Materials (Basel). 2022 Aug 9;15(16):5478. doi: 10.3390/ma15165478.

Abstract

The current study sought to synthesize silver nanoparticles (AgNPs) from Amaryllis vittata (L.) leaf and bulb extracts in order to determine their biological significance and use the toxic plants for human health benefits. The formation of silver nanoparticles was detected by a change in color from whitish to brown for bulb-AgNPs and from light green to dark brown for leaf-AgNPs. For the optimization of silver nanoparticles, various experimental physicochemical parameters such as pH, temperature, and salt were determined. UV-vis spectroscopy, Fourier transform infrared spectroscopy, X-ray dispersion spectroscopy, scanning electron microscopy, and energy dispersion spectroscopy analysis were used to characterize nanoparticles. Despite the fact that flavonoids in plant extracts were implicated in the reduction and capping procedure, the prepared nanoparticles demonstrated maximum absorbency between 400 and 500 nm. SEM analysis confirmed the preparation of monodispersed spherical crystalline particles with fcc structure. The bioinspired nanoparticles were found to show effective insecticidal activity against Tribolium castaneum and phytotoxic activity against Lemna aequincotialis. In comparison to plant extracts alone, the tested fabricated nanoparticles showed significant potential to scavenge free radicals and relieve pain. Antibacterial testing against human pathogenic strains, i.e., Escherichia coli and Pseudomonas aureginosa, and antifungal testing against Aspergillus niger revealed the significant potential for microbe resistance using AgNPs. As a result of the findings, the tested silver nanoparticles demonstrated promising potential for developing new and effective pharmacological and agricultural medications. Furthermore, the effects of biogenic AgNPs on an in vitro culture of Solanum tuberosum L. plants were investigated, and the findings indicated that bulb-AgNPs and leaf-AgNPs produced biomass and induced antioxidants via their active constituents. As a result, bulb-AgNPs and leaf-AgNPs may be recommended for use in Solanum tuberosum L. tissue culture for biomass fabrication and metabolic induction.

Keywords: Amaryllis vittata (L.) Herit; Solanum tuberosum micropropagation; in vitro and in vivo activities; silver nanoparticles; spectroscopy.