title: Silver Nanocomposite Biosynthesis: Antibacterial Activity against Multidrug-Resistant Strains of Pseudomonas aeruginosa and Acinetobacter baumannii.
abstract: Bacterial resistance is an emerging public health issue that is disseminated worldwide. Silver nanocomposite can be an alternative strategy to avoid Gram-positive and Gram-negative bacteria growth, including multidrug-resistant strains. In the present study a silver nanocomposite was synthesized, using a new green chemistry process, by the addition of silver nitrate (1.10-3mol·L-1) into a fermentative medium ofXanthomonasspp. to produce a xanthan gum polymer. Transmission electron microscopy (TEM) was used to evaluate the shape and size of the silver nanoparticles obtained. The silver ions in the nanocomposite were quantified by flame atomic absorption spectrometry (FAAS). The antibacterial activity of the nanomaterial againstEscherichia coli(ATCC 22652),Enterococcus faecalis(ATCC 29282),Pseudomonas aeruginosa(ATCC 27853) andStaphylococcus aureus(ATCC 25923) was carried out using 500 mg of silver nanocomposite.Pseudomonas aeruginosaandAcinetobacter baumanniimultidrug-resistant strains, isolated from hospitalized patients were also included in the study. The biosynthesized silver nanocomposite showed spherical nanoparticles with sizes smaller than 10 nm; 1 g of nanocomposite contained 49.24 µg of silver. Multidrug-resistant strains ofPseudomonas aeruginosaandAcinetobacter baumannii, and the other Gram-positive and Gram-negative bacteria tested, were sensitive to the silver nanocomposite (10-12.9 mm of inhibition zone). The biosynthesized silver nanocomposite seems to be a promising antibacterial agent for different applications, namely biomedical devices or topical wound coatings.
authors.affiliation: Institute of Technology and Research, Tiradentes University, Av. Murilo Dantas 300, 49032-971 Aracaju, SE, Brazil. klebson-biomedico@hotmail.com.|REQUIMTE/LAQV, Department of Chemistry Sciences, Faculty of Pharmacy, University of Porto, R. Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal. klebson-biomedico@hotmail.com.|CAPES Foundation, Ministry of Education of Brazil, 70040-020 Brasília, DF, Brazil. klebson-biomedico@hotmail.com.
authors.forename: Klebson
authors.initials: K
authors.lastname: Silva Santos
authors.affiliation: Institute of Technology and Research, Tiradentes University, Av. Murilo Dantas 300, 49032-971 Aracaju, SE, Brazil. andrielemendonca@yahoo.com.br.
authors.forename: Andriele Mendonça
authors.initials: AM
authors.lastname: Barbosa
authors.affiliation: Institute of Technology and Research, Tiradentes University, Av. Murilo Dantas 300, 49032-971 Aracaju, SE, Brazil. lupeco7@hotmail.com.
authors.forename: Luiz
authors.initials: L
authors.lastname: Pereira da Costa
authors.affiliation: Institute of Technology and Research, Tiradentes University, Av. Murilo Dantas 300, 49032-971 Aracaju, SE, Brazil. malonepinheiro@hotmail.com.
authors.forename: Malone Santos
authors.initials: MS
authors.lastname: Pinheiro
authors.affiliation: REQUIMTE/LAQV, Department of Chemistry Sciences, Faculty of Pharmacy, University of Porto, R. Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal. beatoliv@ff.up.pt.
authors.forename: Maria Beatriz Prior Pinto
authors.initials: MB
authors.lastname: Oliveira
authors.affiliation: Institute of Technology and Research, Tiradentes University, Av. Murilo Dantas 300, 49032-971 Aracaju, SE, Brazil. fpadilha@yahoo.com.
authors.forename: Francine
authors.initials: F
authors.lastname: Ferreira Padilha
keywords: Acinetobacter baumannii; Pseudomonas aeruginosa; antibacterial activity; multidrug-resistance; silver nanocomposite biosynthesis