Lane 1, DNA molecular weight marker. Lane 2, control plasmid without silver nanoparticles showing only supercoiled plasmid band that moves ahead of relaxed circular and linear plasmids. Lane 3, plasmid incubated with 0.51 μg nanoparticles showing disappearance

of the supercoiled plasmid band and appearance of relaxed circular and linear plasmid bands along with smaller fragmented DNA. Lane 4, plasmid incubated with 1.02 μg nanoparticles. Lane 5, plasmid incubated with 2.55 μg nanoparticles. Lane 6, plasmid incubated with 3.57 μg nanoparticles showing gradual degradation GDC941 of the fragmented DNA bands; and lane 7, plasmid incubated with 5.1 μg nanoparticles showing more degradation of DNA. Conclusions In this study, phytopathogenic fungus M. phaseolina (Tassi) Goid was used for the first time for the extracellular biosynthesis of silver nanoparticles by

bioreduction of aqueous Ag + ion. SEM, TEM, and AFM were used to study the morphology, concentration, and size of biosynthesized nanoparticles. The silver nanoparticles exhibited distinct antimicrobial property on multidrug-resistant human and plant pathogenic bacteria. An 85-kDa protein present in the extracellular solution was responsible for synthesis and capping of nanoparticles. This eco-friendly, cost-effective extracellular Mizoribine in vivo biosynthesis of naturally protein-capped silver nanoparticles with potent antimicrobial activities from the phytopathogenic fungus has the potential to be utilized on a large scale for widespread industrial or 4SC-202 in vitro medical application. Acknowledgements This work was partially supported by the Department of Biotechnology, Ministry of Science and Technology, Government of India (DBT). SC is thankful to University Grants Commission (UGC-NET), New Delhi, and AB is thankful to the Council for Scientific and Industrial Research (CSIR-NET), New Delhi for providing senior research

fellowship. We also thank the AFM facility of DBT-IPLS, Center for Modern Biology, University of Calcutta and transmission electron microscope facility of Center for Research in Nanoscience and Nanotechnology (CRNN), University of Calcutta, XRD facility of Central Glass and Ceramics Research Institute, Kolkata, and the Scanning Electron Microscope Montelukast Sodium facility, Bose Institute, Kolkata. Electronic supplementary material Additional file 1: Figure S1: Atomic force microscopy of the silver nanoparticles. (a) AFM images showing top view of the silver nanoparticles. (b) AFM showing three-dimensional view of the nanoparticles. (c) Graphical profile for heights of the nanoparticles based on AFM image. (PPT 210 KB) References 1. Mohanpuria P, Nisha K, Rana NK, Yadav SK: Biosynthesis of nanoparticles: technological concepts and future applications. J Nanopart Res 2008, 10:507–517.CrossRef 2. Sharma VK, Yngard RE, Lin Y: Silver nanoparticles: green synthesis and their antimicrobial activities. Adv Colloid Interface Sci 2009, 145:83–96.