ANTIMICROBIAL ACTIVITY AGAINST Escherichia coli OF NANOPARTICLES OBTAINED BY DIFFERENT SYNTHESIS METHODS

M.R. ESQUIVEL; J.G. FERNÁNDEZ; C.D.L.A. FERNÁNDEZ; A. AMADOR; M.D.L.A. CANGIANO

San Luis

Congreso; Sociedad de Biología de Cuyo; 2019

Universidad Nacional de San Luis

Escherichia coli, is a pathogenic bacterium that causes serious infections, whose therapeutic treatment is threatened by the emergence of multiple resistance to conventional antibiotics. In recent years, metal nanoparticles (NP) have been studied for their antimicrobial capacity and its possible applications as an alternative to antibiotics against different pathogens. The NPs also vary in synthesis techniques; either by chemical, physical and biological based methods. The objective of this work was to study the possible antimicrobial capacity of nanoparticles obtained by methods chemical and biological against E. coli. The NPs obtained by a method chemical called citrate- gel (Quim-NP CuNi B1-300; Quim-NP CuNi B1-500; Quim-NP CuNi B3-300) and NPs obtained by a method biological, silver nanoparticles (AgNPs), synthesized by biological mediators such as, Cryptococcus laurentii (AgNPs-C.l) and Rhodotorula glutinis (AgNPs-R.g). The antimicrobial capacity of the aforementioned NPs was evaluated in vitro by means of the agar diffusion method; 200 μL of an E. coli (ATCC 8739) suspension, at a concentration of 3x108 CFU mL-1, were seeded in 10 cm Petri dishes with selective medium and incubated for 1 h at 37°C+1. Subsequently, wells of 3 mm were made aseptically and were filled with 25 μL of the suspensions of AgNPs-R.g, AgNPs-C.l, CuNi B1-300; CuNi B1-500, CuNi B3-300 and the combination thereof. Distilled water was used with negative control. Then they were incubated for 48 hours at 37°C+1. After incubation, the zones ofinhibition (cm) were measured. The assays were performed in triplicate. Most of the NP evaluated showed antibacterial activity against E. coli. When combining chemical and biological NPs, synergistic effects are observed with an increase in antibacterial activity in some cases. We can conclude that NP derived from chemical and biological synthesis could be used as antimicrobials against E. coli and when these are combining, the antibacterial effects are increase. In the future these applications of nanomaterials could be used as an alternative to the use of antibiotics against pathogen-resistant.