Silver Nanoparticles Synthesized through Green Methods UsingEscherichia coliTop 10 (Ec-Ts) Growth Culture Medium Exhibit Antimicrobial Properties against Nongrowing Bacterial Strains

Abstract

Finding novel antibiotics and antimicrobial materials has become of great importance to modern society due to the alarming increase in the development of multidrug resistance in various bacterial strains. This problem is even more complex when infections involve bacterial strains in stationary metabolic states, since most of the antibiotics found in the market do not have an effect on bacteria in dormant metabolic states. A promising field to aid in the solution of this problem is nanotechnology, since it offers a wide avenue for the development of potential therapeutics, specifically the use of silver metal nanoparticles. Silver nanoparticles have proven to be highly effective antimicrobial agents and excellent candidates to be engineered and designed into clever delivery systems, taking advantage of their rapid and potent toxicity on prokaryotic cells at low concentrations. Metal nanoparticles are most commonly synthetized through one or a series of redox chemical reactions using powerful but environmentally toxic-reducing agents. Therefore, in this work, we propose a biosynthesis method that allows the production of nanoparticles, with homogenous shapes and narrow size distributions, through an environmentally friendly technique that does not produce toxic residues. Here, silver nanoparticles were produced from silver salt (AgNO3) using three different growth culture media residues from E. coli top 10. The three different culture media residues used included LB, LBN, and LBE; all of them displaying a different chemical and nutrient composition. Here, after characterization of the different silver nanoparticles produced with the different media, we demonstrated that the LB culture-conditioned media was the most suitable to produce them since they displayed the most narrow size distribution, with an average 10.6 nm in diameter, a relatively low standard deviation of 5.5 nm, and a narrow UV-vis spectrum absorption peak at 420 nm. The other methods presented larger nanoparticle sizes and broader size distributions. Furthermore, nanoparticles produced with LB Lennox were found to be, at very low concentrations, effective antimicrobial agent against E. coli top 10 at stationary phase. Therefore, these results seem to contribute knowledge linked to the production of antimicrobial nanoparticles (Ag-NPs) through green synthesis and represent a platform to treat infections caused by nongrowing bacteria.

Tunable photoluminescence properties of selenium nanoparticles: biogenic versus chemogenic synthesis

“…Similar results were recently reported for the synthesis of AgNPs by Klebsiella pneumoniae, Escherichia coli, and Pseudomonas jessinii, as well as SeNPs produced by Azospirillum brasilense, where the authors recognized that differences in the composition of the growth media used strongly affected size and shape of the NPs [53][54][55][56]. In this regard, the meat extract present as "Lab-Lemco powder" in NB constituted an additional nutrient for SeITE02 cells, which was absent in LB.…”

“…In this regard, the meat extract present as "Lab-Lemco powder" in NB constituted an additional nutrient for SeITE02 cells, which was absent in LB. Therefore, the more complex composition and nutritional power of NB with the respect of LB may have influenced bacterial cells from a metabolic perspective, giving: (i) a less controlled and overall faster SeO 3 2− bioconversion, (ii) the occurrence of multiple nucleation events for NP growth, and (iii) the synthesis of SeNPs heterogeneous in size [55]. Considering the variation in size of biosynthesized SeNPs, for comparison, different Na 2 SeO 3 :L-cysteine ratios (1:3 and 1:4) [48] were used to obtain chemogenic NPs (L-cys SeNPs_1:3 and L-cys 3E).…”

Potential Decontamination of Drinking Water Pathogens through k-Carrageenan Integrated Green Bottle Fly Bio-Synthesized Silver Nanoparticles

“…The produced nanoparticles are almost homogenous in their shapes and have narrow size distributions. In addition, the green methods are ecofriendly and cost-effective methods that do not produce toxic residues [10,11].…”

Green Synthesis of Metallic Nano-Particles and Their Potential in Bio-Medical Applications

“…Table 1 is the list of gold nanoparticles fabrication by bacteria, fungi, algae, and plants explaining the different features of the production of gold nanoparticles. [42,46]. An extensive volume of literature reported successful nanoparticle synthesis using various plants, such as V. amygdalina, N. sativa, W coagulans, C. illinoinensis [39,[47][48][49].…”