Rapid biosynthesis and characterization of silver nanoparticles from the leaf extract of Tropaeolum majus L. and its enhanced in-vitro antibacterial, antifungal, antioxidant and anticancer properties.

Eco-friendly biosynthesis of nanoparticles from medicinal plants as reducing agent has gained importance due to its potential therapeutic uses. In the present study Silver nanoparticles (AgNPs) were eco-friendly synthesized using the leaf extracts of the medicinal plant Tropaeolum majus. The obtained AgNPs were characterized by UV - visible spectrum, FTIR, SEM and XRD which clearly showed the reduction of Ag⁺ ions to Ag⁰. In addition, the aqueous and ethanolic extracts were analyzed for phytochemicals and its antioxidant activities. GC-MS spectrum showed the presence of 25 compounds with benzeneacetic acid as the dominant contents. The synthesized AgNPs revealed maximum absorption spectrum at 463 nm and FTIR vibrational peaks at 3357.46, 21,966.52, 2118.42, 1637.27, 658.571 and 411.728 cm^-1 respectively. SEM and XRD studies evidenced the nature of nanocrystalline with face centered cubic (fcc) crystal structure. Both AgNPs and plant extracts showed more inhibition activity against Pseudomonas aeroginosa compared to other bacteria with MIC value of 6.25 μg/ml. Antifungal activities was higher for Penicilium notatum with MIC value 31.2 μg/ml. The IC50 values for MCF7 for aqueous extract were found to be 4.68 μg/ml, ethanol extract 7.5 μg/ml, AgNPs 2.49 μg/ml, and doxorubicin 1.4 μg/ml. The IC50 values for VERO cell line for aqueous extract was 8.1 μg/ml, ethanol extract with 6.8 μg/ml, silver nanoparticles 5.3 μg/ml and doxorubicin 2.6 μg/ml respectively. Conclusively, the antibacterial, antifungal, antioxidant and anticancer properties of the synthesized AgNPs from Tropaeolum majus act as major therapeutic drug for microbial infectious disease and other health associated disorders.