Comparative study of the antimicrobial activity of silver nanoparticles obtained from Tagetes erecta (Cempasúchil) by green synthesis

Abstract

Nanomaterials’ application can provide solutions to technological and environmental challenges, in the areas of solar energy conversion, catalysis, medicine and water treatment. Silver nanoparticles (Ag-Np's) stand out for their potential and versatility, due to their optical, electrical, mechanical, and structural properties, their photoactivity promotes them as an antimicrobial agent (bactericide-fungicide). The effect caused by Ag ions in microorganisms is already known, however, the mechanism of action is still not entirely clear. In the present study, silver nanoparticles were synthesized using the Cempasúchil flower (Tagetes erecta) extract as a reducer by a simple and ecological route. Aqueous silver ions exposed to the flower extract were reduced, leading to silver nanoparticles’ biological synthesis. The silver nanoparticles were characterized by UVvisible spectroscopy, where it showed a maximum peak from 410 nm to 425 nm. The silver nanoparticles’ synergistic antimicrobial potential was evaluated with the following microorganisms: Escherichia coli and Aspergillus niger, through the Kirby-Bauer method, where inhibition halos of 2 to 2.2 cm were obtained, showing the antimicrobial activity of the Ag-Np' s.