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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.

Microbial resistance, oxidative stress, and inflammatory conditions are among the leading causes of death worldwide. In the current work, silver nanoparticles (AgNPs) were biosynthesized using the aqueous extracts of parsley, corn silk (CS), gum Arabic (GA) or combination of the three extracts. The formed nanoparticles were characterized using three techniques including transmission electron microscopy (TEM), UV-visible spectrophotometer and Fourier-transform infrared spectroscopy (FTIR). The antioxidant, anti-inflammatory, and antimicrobial activities were tested for the formed nanoparticles, the aqueous extracts of each of the three plants and their combination. Oxidative stress was induced by alloxan which promoted the development of diabetes mellitus in rats. Inflammation was induced by injecting carrageenan in rats' paws. Pathogenic microorganisms causing serious urinary tract infection (UTI) were selected for the antimicrobial assay. All aqueous extracts and the biosynthesized AgNPs showed variable degrees of antioxidant, anti-inflammatory and antimicrobial activities, however, the AgNPs biosynthesized by the combination of the three aqueous extracts was the most effective one. LC/MS was done to identify the compounds present in the crude extracts that may be responsible for the observed biological activities. LC/MS resulted in the identification of 13 compounds. Docking experiments on COX-1 (cyclooxygenase-1) and COX-2 (cyclooxygenase-2) were performed to determine the compounds responsible for the antiinflammatory activity of the extracts. The results showed that silver nanoparticles synthesized by the combination of the three aqueous extracts are considered promising candidates for the development of antioxidant, anti-inflammatory and antimicrobial agents. photochemical [10], electrochemical [7, 11], reverse micelle [12], thermal decomposition [13], radiation [7,14] and microwave-assisted [7] methods. Most of these methods require the use of hazardous chemicals and high energy for the preparation of nanoparticles. Biological synthesis of nanoparticles involves the use of natural materials such as plants, bacteria, fungi [1,5,15]. The use of plants for the synthesis of nanoparticles have an advantage over other biological methods as it does not involve the use of cell culture, and does not need longer incubation time required for the reduction of metal ions [16,17]. Plants are known to contain various secondary metabolites such as alkaloids, terpenoids, flavonoids and tannins which provide suitable reducing and surface agents for the nanoparticle synthesis and stabilization. Biopolymers such as cellulose, chitosan, alginate, dextran and tree gums are another family of natural sources which were used for the reduction and stabilization of nanoparticles [17,18].Recently, pathogenic bacteria and fungi such as Staphylococci spp., Enterococci spp., Klebsiella pneumoniae, and Pseudomonas spp. demonstrated resistance to commercially available antimicrobial agents at an increasing rate and has become a global thr...

The Caspian Locust is the common name of Gleditsia caspica, a tree cultivated in the southern and western Caspian Sea in Russia and Iran. Herein, a qualitative characterization of the chemical constituents of Gleditsia caspica leaves extract using ultra-performance liquid chromatography coupled to electrospray ionization tandem mass fragmentation (UPLC-ESI/MS/MS) analysis was performed revealing the presence of nine compounds: six flavonoids, one triterpenoid, one phytosterol, and one long chain ester. Six compounds were newly reported from Gleditsia caspica and two for the first time from genus Gleditsia. Moreover, the in-vivo anti-inflammatory activities of two different doses; 50 and 100 mg/kg of the aqueous-alcoholic extract of Gleditsia caspica leaves were evaluated in the carrageenaninduced paw edema model. The percentage of edema inhibition was calculated after 1, 2, 3, and 4 h of the administration showing a significant reduction in edema thickness in a dose and time-dependent manner compared to the control drug, indomethacin. These results put forward Gleditsia caspica extract as a potential natural anti-inflammatory agent with minimal side effects.