Yeast-derived biosynthesis of silver/silver chloride nanoparticles and their antiproliferative activity against bacteria

Eugenio, M., Müller, N., Frasés, S., Almeida-Paes, R., Lima, L. M. T.R., Lemgruber, L. , Farina, M., de Souza, W. and Sant'Anna, C. (2016) Yeast-derived biosynthesis of silver/silver chloride nanoparticles and their antiproliferative activity against bacteria. RSC Advances, 6(12), pp. 9893-9904. (doi: 10.1039/c5ra22727e)

Abstract

Here, we provide the first evidence of yeast strains assisted Ag/AgCl-NPs production in vitro. The formed nanoparticles were characterized by spectroscopic and electron microscopy approaches. UV-vis supported the biosynthesis. TEM analysis evidenced that the nanoparticles mainly presented a circular shape and their diameters varied mostly being in the range 2 to 10 nm. XRD analysis showed a crystalline structure, with diffraction peaks corresponding to metallic silver and silver chloride nanoparticles, and when analyzed by high-resolution transmission electron microscopy (HRTEM), instead of being round, (111) (octahedral) and (200) (cubic) symmetry facets appeared systematically in one side of the nanoparticles. Analysis of ultra-thin sections by TEM indicated that the domain of the synthesis of Ag/AgCl-NPs was mainly between the cell wall and the plasma membrane. By using 3D reconstruction obtained from focused ion beam scanning electron microscopy (FIB/SEM) the spatial distribution of the domains of nanoparticle synthesis was mapped and nanoaggregates of Ag/AgCl-NPs up 35 nm in diameter were observed. Extracellular synthesis also occurred; in accordance with the fact that conditioned media from yeast isolates were as efficient at producing Ag/AgCl-NPs as live-cell cultures. Exposure of Gram-positive Staphylococcus aureus and Gram-negative Klebsiella pneumoniae cultures to Ag/AgCl-NPs led to a strong growth inhibition as shown by optical density measurements. The Ag/AgCl-NPs described here have characteristics compatible with a strong potential for use in the biotechnology industry, particularly for biomedical applications.

• Item Type: Articles
• Additional Information: This work was supported by National Council for Scientific and Technological Development (CNPq), the Carlos Chagas Filho Foundation for Research Support of the State of Rio de Janeiro (FAPERJ) and Coordination for the Improvement of Higher Education Personnel (CAPES).
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Lemgruber Soares, Dr Leandro
• Authors: Eugenio, M., Müller, N., Frasés, S., Almeida-Paes, R., Lima, L. M. T.R., Lemgruber, L., Farina, M., de Souza, W., and Sant'Anna, C.
• College/School: College of Medical Veterinary and Life Sciences > School of Infection & Immunity
• Journal Name: RSC Advances
• Publisher: Royal Society of Chemistry
• ISSN: 2046-2069
• ISSN (Online): 2046-2069
• Copyright Holders: Copyright © 2016 The Royal Society of Chemistry
• First Published: First published in RSC Advances 6(12):9893-9904
• Publisher Policy: Reproduced in accordance with the publisher copyright policy