Nuclear chemistry

Nanoparticle

Ecology

Bacteria

Biology

Antimicrobial

Materials science

Terminalia arjuna

Dynamic light scattering

Antibacterial activity

Botany

Silver nanoparticle

Silver nitrate

Terminalia

Genetics

Nanotechnology

Organic chemistry

Microbiology

Bark (sound)

Chemistry

Biomolecules

This work reports an eco-friendly synthesis of silver nanoparticles (AgNPs) using endophytic bacteria, Cytobacillus firmus isolated from the stem bark of Terminalia arjuna. The synthesis of AgNPs was confirmed by visual observation as a change in color of the bacterial solution impregnated with silver. Further, the morphology of the AgNPs, average size, and presence of elemental silver were characterized by UV–Visible spectroscopy, scanning electron microscopy, and dynamic light scattering spectroscopy. The roles of endophytic secondary metabolites in the metal reduction, stabilization, and capping of silver nanoparticles were studied by qualitative FTIR spectral peaks. The antimicrobial ability of AgNPs was evaluated against Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria and pearl millet blast disease-causing fungi (Magnoporthe grisea). The biosynthesized AgNPs showed good antibacterial and antifungal activities. AgNPs effectively inhibited the bacterial growth in a dose-dependent manner and presented as good antifungal agents towards the growth of Magnoporthe grisea.

Green Synthesis of Silver Nanoparticles by Cytobacillus firmus Isolated from the Stem Bark of Terminalia arjuna and Their Antimicrobial Activity