Biofabrication of silver nanoparticles from endemic variety Garcinia gummi-gutta var. papilla of the Western Ghats: characterisation, antibacterial and catalytic activity

Nanotechnology based on plants is a new field that has applications ranging from health to environmental sustainability. In this work, silver nanoparticles were synthesised from the leaves of an endemic variety of Garcinia in the Western Ghats: Garcinia gummi-gutta var. papilla. In this study, after optimizing various parameters spectrophotometric synthesis of silver nanoparticles was successfully accomplished within 2 h at 60 °C using 20 ml of leaf extract and 4 mM AgNO₃ solution. Biosynthesized AgNPs were characterised using UV–Visible spectroscopy, fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and dynamic light scattering devices (DLS).In the UV–Vis spectrum, a maximum absorption band of 416 nm was obtained. Spherical particles with an average size of 65.62 nm through SEM and a hydrodynamic size of 111.8 nm from DLS were observed. Important functional groups that are involved in the synthesis of AgNPs were determined through FTIR. Antibacterial efficacy of the synthesised AgNPs was determined through the disc diffusion method against Pseudomonas aeruginosa (ATCC 27853) and Staphylococcus aureus (ATCC 25923). Garcinia gummi-gutta var. papilla showed higher antibacterial activity against gram-negative bacteria than gram-positive bacteria. The catalytic activity of AgNPs was studied using methylene blue. In 8 min, 90% degradation has been observed.