Silver nanoparticles were synthesized from Ehretia laevis Roxb. leaf extract by one-step green synthesis method. The nanoparticles were crystalline in nature, spherical shaped with 25 to 35 nm diameter. The aim of this study was the synthesis and characterization of silver nanoparticles from Ehretia laevis Roxb., and the evaluation of their antimicrobial, anticancer, larvicidal and methylene blue dye degradation efficiency. The nanoparticles showed antimicrobial, larvicidal and cytotoxic activity. At a concentration of 25 μg/mL, it killed 70 ± 10.24% of Culex quinquefasciatus larvae after 72 h treatment. The median lethal concentration of the nanoparticles against HeLa, human cervical cancer cells, and MCF-7 human breast cancer cells, were calculated to 12.7 μg/mL and 14.5 μg/mL, respectively. The synthesized nanoparticles degraded Congo red ~ 85% within 8 h at a concentration of 200 μg/mL. Possible application of the synthesized nanoparticles are water purifying agent in presence of sunlight.

To evaluate the bactericidal, and cytotoxicity properties of silver nanoparticles synthesized from root extract of Asparagus racemosus. The physical properties of these nanoparticles were characterized by Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM), XRD and UV-Vis spectrophotometric analysis. The biochemical properties were assayed by antibacterial study, cytotoxicity assay using cancer cell line. The formation of silver nanoparticles was confirmed by UV-VIS spectroscopic analysis which showed absorbance peak at 420 nm. X-ray diffraction photograph indicated the face centered cubic structure of the synthesized AgNPs. TEM has displayed the different dimensional images of biogenic silver nanoparticles with particle size distribution ranging from 30-50 nm. Silver particles are spherical in shape. The EDX analysis was used to identify the elemental composition of synthesized AgNPs. Antibacterial activity of the synthesized AgNPs against three Gram positive and Gram negative bacteria strains like Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa carried out showed significant zones of inhibition. The cytotoxicity study by AgNPs also showed cytotoxicity on ovarian cancer cell line PA-1. The present study confirms that the AgNPs have great promise as antibacterial, and anticancer agent.

Green synthesis of silver nanoparticles (AgNPs) is gaining momentum in the field of nano-research. Scoparia dulcis leaves were used as a reducing agent for the synthesis of silver nanoparticles from an aqueous solution of silver nitrate (AgNO₃). Synthesized AgNPs were characterized by UV-Vis spectroscopy, XRD, SEM with EDAX and TEM. UV-VIS surface plasmon resonance spectroscopy was observed at 430 nm. XRD data depicts that the NPs are crystalline in nature. The EDAX data indicate that 63.76% presence of Ag metal. The TEM & SEM results indicate that size of the AgNPs ranges from 15-25 nm. The results also support that spherical shape of the nanoparticles. In addition, the NPs are in polydispersed condition. The antimicrobial activities indicate significant inhibition of the growth of three pathogenic bacteria such as Pseudomonas ariginosa, Bacillua subtillis and Staphylococcus aureous. Cytotoxicity of this nanoparticle showed that this Ag-NP also has more cytotoxic effect on a lung cancer cell line, A549 cells compared to ovarian cancer cell line, PA1 indicating a possible therapeutic use of this AgNP.