Biosynthesis, optimization and characterization of ZnO nanoparticles using Bacillus cereus MN181367 and their antimicrobial activity against multidrug resistant bacteria

Nano-ZnO has been successfully implemented in particles, rods, and tubes nanostructures via sol-gel and hydrothermal techniques. The variation of the different preparation parameters such as reaction temperature, time, and stabilizer agents was optimized to attain different morphological structures. The influence of the microwave annealing process on ZnO crystallinity, surface area, and morphological structure was monitored using XRD, BET, and SEM techniques, respectively. The antimicrobial activity of zinc oxide produced in nanotubes structure was examined against four different multidrug resistant bacteria: Gram-positive (Staphylococcus aureusandBacillus subtilis) and Gram-negative (Escherichia coliandPseudomonas aeruginosa) strains. The activity of produced nano-ZnO was determined by disc diffusion technique and the results revealed that ZnO nanotubes recorded high activity against the studied strains due to their high surface area equivalent to 17.8 m2/g. The minimum inhibitory concentration (MIC) of ZnO nanotubes showed that the low concentrations of ZnO nanotubes could be a substitution for the commercial antibiotics when approached in suitable formula. Although the annealing process of ZnO improves the degree of material crystallinity, however, it declines its surface area and consequently its antimicrobial activity.

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Antimicrobial activity of some seaweeds species from Red sea, against multidrug resistant bacteria

The Egyptian Journal of Aquatic Research ◽

10.1016/j.ejar.2015.11.006 ◽

2016 ◽

Vol 42 (1) ◽

pp. 65-74 ◽

Cited By ~ 48

Author(s):

Shimaa M. El Shafay ◽

Samh S. Ali ◽

Mostafa M. El-Sheekh

Keyword(s):

Antimicrobial Activity ◽

Red Sea ◽

Multidrug Resistant ◽

Resistant Bacteria ◽

Multidrug Resistant Bacteria

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The Spectrum of Design Solutions for Improving the Activity-Selectivity Product of Peptide Antibiotics against Multidrug-Resistant Bacteria and Prostate Cancer PC-3 Cells

Molecules ◽

10.3390/molecules25153526 ◽

2020 ◽

Vol 25 (15) ◽

pp. 3526

Author(s):

Davor Juretić ◽

Anja Golemac ◽

Denise E. Strand ◽

Keshi Chung ◽

Nada Ilić ◽

...

Keyword(s):

Prostate Cancer ◽

Antimicrobial Activity ◽

Anticancer Activity ◽

Wide Spectrum ◽

Multidrug Resistant ◽

Cell Penetrating Peptides ◽

Resistant Bacteria ◽

Peptide Antibiotics ◽

Multidrug Resistant Bacteria ◽

Selective Antimicrobial Activity

The link between the antimicrobial and anticancer activity of peptides has long been studied, and the number of peptides identified with both activities has recently increased considerably. In this work, we hypothesized that designed peptides with a wide spectrum of selective antimicrobial activity will also have anticancer activity, and tested this hypothesis with newly designed peptides. The spectrum of peptides, used as partial or full design templates, ranged from cell-penetrating peptides and putative bacteriocin to those from the simplest animals (placozoans) and the Chordata phylum (anurans). We applied custom computational tools to predict amino acid substitutions, conferring the increased product of bacteriostatic activity and selectivity. Experiments confirmed that better overall performance was achieved with respect to that of initial templates. Nine of our synthesized helical peptides had excellent bactericidal activity against both standard and multidrug-resistant bacteria. These peptides were then compared to a known anticancer peptide polybia-MP1, for their ability to kill prostate cancer cells and dermal primary fibroblasts. The therapeutic index was higher for seven of our peptides, and anticancer activity stronger for all of them. In conclusion, the peptides that we designed for selective antimicrobial activity also have promising potential for anticancer applications.

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