Síntese de nanopartículas metálicas de prata (AgNPs) e ouro (AuNPs) empregando extrato de Spondias mombin L. para potencial aplicação na medicina veterinária

Abstract

Research in the area of nanotechnology that involves the preparation of metallic nanoparticles using alternative methods has been disseminated through the Green Chemistry approach, and, in view of the various problems that permeate conventional methods, new mediations that are not harmful to the environment, allow exploring procedures that employ natural resources such as the use of plant extracts for the synthesis of metallic nanoparticles. In this context, the present work aimed to prepare gold and silver nanoparticles, using the decoction of S. mombin L. leaves with a view to veterinary application due to the antimicrobial potential of these solutions. Gold nanoparticles and silver nanoparticles were obtained in two ways, the first using the conventional method, reducing their respective salts. In the second methodology, the preparation followed what was used in the conventional method, but the only difference was the replacement of reducing agents with S. mombin L. decoction to reduce salts. The present work sought to research parameters with the aid of electronic absorption spectroscopy in the UV-Vis region to understand the formation of nanoparticles using different concentrations of S. mombin L decoction. Transmission electron microscopy analysis confirmed that gold nanoparticles and silver, as well as those to which decoction was added, presented different geometric shapes, such as spherical and triangular, with average particle diameters varying between 18.007 and 33.875 nm. The antibacterial activity of silver and gold nanoparticles associated with Spondia mombin L. was carried out using the broth microdilution method at times zero and after 24 hours for the strains Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli and Klebisiella pneumonie. For statistical analysis, the results of the microbiological analyzes were subjected to analysis of variance and the means compared with each other using the Tukey test, at a level of 5% probability, using the agricole package implemented in R statistical language. bactericidal activity were carried out only with silver nanoparticles and silver associated with Spondia mombin L. decoction, as gold nanoparticles associated with Spondia mombin L. did not show bacterial action. Finally, regarding the minimum inhibitory concentration and minimum bactericidal concentration, it is concluded that the silver nanoparticles associated with Spondias mombin L. decoction have significant effects on bacterial activities, with total inhibition of Gram-positive and Gram-negative bacteria occurring in concentration of 50 mg/mL- 1.