Biosynthesis and characterization of silver nanoparticles and antimicrobial activity of Trichoglottis tenera (Lindl.) an endangered orchid of Western Ghats

This research paper deals with a rapid and eco-friendly method for green synthesis of nanoparticles. The research was also conducted to evaluate the therapeutic potentials of silver nanoparticles isolated from orchids plant extracts in five different concentrations (I-99 (ml) 1mM silver nitrate +1ml plant extract, II-98+2, III-97+3, IV-96+4, and V-95+5) and various time periods was used to study green synthesis of nanotechnology. The five isolated silver compounds were used to investigate the antimicrobial potential against ten clinical bacteria (Escherichia coli, Vibrio cholerae, Serratia marcesens, Staphylococcus mutants, Staphylococcus aureus, Bacillus subtilis, Salmonella typhi, Klepsiella pneumonia, Proteus vulgaris, and Pseudomonas aurogens) and three fungal species Aspergillus flavus, Candida albicans, and Trichophyton mentagrophytes. Out of five isolated silver compounds, fourth and fifth were found to exhibit antimicrobial properties with potential to fight against E.coli, Bacillus subtilis, and Salmonella typhi. The result shows moderate activity in third and fourth silver compounds against Shigiella sonehi, Vibrio cholerae and Pseudomonas aurogens. The first and second isolated silver compounds were failed to show any antibacterial activity against Klepsiella pneumonia, Staphylococcus mutans, Staphylococcus aureus, and Proteus vulgaris. The synthesis of silver nanoparticles (AgNPs) was characterized by UV-visible spectroscopy, FTIR-Fourier Infrared spectroscopy, scanning electron microscopy (SEM), and X-ray diffraction (XRD). The UV-Vis spectroscopy has given surface Plasmon resonance for the synthesis of silver nanoparticles in extract-I, extract-II, extract-III, extract-VI, and extract-V. It was generated in ten different time periods at 422 nm to 447 nm in all the five extracts. Scanning electron microscopy (SEM) images were obtained in different shapes like nano rods (500 nm).