Green Synthesis of Silver Nanoparticles by <i>Cytobacillus firmus</i> Isolated from the Stem Bark of <i>Terminalia arjuna</i> and Their Antimicrobial Activity
Sujesh Sudarsan,
Madan Kumar Shankar,
Anil Kumar Belagal Motatis,
Sushmitha Shankar,
Darshan Krishnappa,
Chakrabhavi Dhananjaya Mohan,
Kanchugarakoppal S. Rangappa,
Vijai Kumar Gupta,
Chandra Nayaka Siddaiah
Affiliations
Sujesh Sudarsan
Department of Studies in Biotechnology, University of Mysore, Manasagangotri, Mysore 570006, India
Madan Kumar Shankar
Institute of Excellence, VijnanaBhavan, University of Mysore, Manasagangotri, Mysore 570006, India
Anil Kumar Belagal Motatis
Department of Studies in Biotechnology, University of Mysore, Manasagangotri, Mysore 570006, India
Sushmitha Shankar
Department of Studies in Biotechnology, University of Mysore, Manasagangotri, Mysore 570006, India
Darshan Krishnappa
Department of Studies in Biotechnology, University of Mysore, Manasagangotri, Mysore 570006, India
Chakrabhavi Dhananjaya Mohan
Department of Studies in Molecular Biology, University of Mysore, Manasagangotri, Mysore 570006, India
Kanchugarakoppal S. Rangappa
Department of Studies in Chemistry, University of Mysore, Manasagangotri, Mysore 570006, India
Vijai Kumar Gupta
Center for Safe and Improved Food, Scotland’s Rural College (SRUC), Kings Buildings, West Mains Road, Edinburgh EH9 3JG, UK
Chandra Nayaka Siddaiah
Department of Studies in Biotechnology, University of Mysore, Manasagangotri, Mysore 570006, India
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.
