Anti-Alzheimer potential, metabolomic profiling and molecular docking of green synthesized silver nanoparticles of Lampranthus coccineus and Malephora lutea aqueous extracts.

The green synthesis of silver nanoparticles (SNPs) using plant extracts is an eco-friendly method. It is a single step and offers several advantages such as time reducing, cost-effective and environmental non-toxic. Silver nanoparticles are a type of Noble metal nanoparticles and it has tremendous applications in the field of diagnostics, therapeutics, antimicrobial activity, anticancer and neurodegenerative diseases. In the present work, the aqueous extracts of aerial parts of Lampranthus coccineus and Malephora lutea F. Aizoaceae were successfully used for the synthesis of silver nanoparticles. The formation of silver nanoparticles was early detected by a color change from pale yellow to reddish-brown color and was further confirmed by transmission electron microscope (TEM), UV-visible spectroscopy, Fourier transform infrared (FTIR) spectroscopy, dynamic light scattering (DLS), X-ray diffraction (XRD), and energy-dispersive X-ray diffraction (EDX). The TEM analysis of showed spherical nanoparticles with a mean size between 12.86 nm and 28.19 nm and the UV- visible spectroscopy showed λmax of 417 nm, which confirms the presence of nanoparticles. The neuroprotective potential of SNPs was evaluated by assessing the antioxidant and cholinesterase inhibitory activity. Metabolomic profiling was performed on methanolic extracts of L. coccineus and M. lutea and resulted in the identification of 12 compounds, then docking was performed to investigate the possible interaction between the identified compounds and human acetylcholinesterase, butyrylcholinesterase, and glutathione transferase receptor, which are associated with the progress of Alzheimer's disease. Overall our SNPs highlighted its promising potential in terms of anticholinesterase and antioxidant activity as plant-based anti-Alzheimer drug and against oxidative stress.

Antimicrobial wound dressing and anti-inflammatory efficacy of silver nanoparticles.

Powdered silver nanoparticles (AgNPs) were successfully prepared through addition of AgNO3 to alkali dissolved starch followed by precipitation with ethanol. AgNPs aqueous suspensions were prepared from powder AgNPs by dispersion and dilution with water. Wound dressings were obtained by treating cotton fabrics with different concentrations of AgNPs aqueous suspensions (60, 125 and 250 ppm). The as prepared AgNPs were characterized using UV-vis spectroscopy, transmission electron microscopy (TEM), particle size analyzer, polydispersity index (PdI), zeta potential. The prepared AgNPs powder had particle size value (22 nm), polydispersity index (0.163) and zeta potential (-28 mV) indicating the formed AgNPs had small and well stabilized particles. The treated cotton fabrics were characterized by making use of SEM-EDX. Cotton fabrics containing 250 ppm AgNPs were more effective against different species of organisms than those containing 60 and 125 ppm. The results of potent healing using fabrics treated with 250 ppm AgNPs indicate that it leads to similar results compared with that of the Dermazin cream. Moreover, the anti-inflammatory effect AgNPs is nearly similar to 20 ml dose of the reference indomethacin drug.