| Autor: |
El-Zahed, Mohamed M., Baka, Zakaria A. M., Abou-Dobara, Mohamed I., El-Sayed, Ahmed K. A. |
| Předmět: |
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| Zdroj: |
Jordan Journal of Biological Sciences; Jun2023, Vol. 16 Issue 2, p279-288, 10p |
| Abstrakt: |
Silver nanomaterials are usually applied as antimicrobial agents; however, they can cause toxic effects on human health. The current investigation was performed to study the combined effects of chitosan and silver nanoparticles (AgNPs) using the cell-free supernatant of Escherichia coli (MF062579). The produced chitosan/silver nanocomposite (CS/AgNC) showed good antibacterial activity and high stability. The biosynthesized CS/AgNC contained homogeneous spherical AgNPs with an average size of ~12.3 nm and a net surface charge of +30.9 ± 3.2 mV. CS/AgNC revealed a good minimum inhibitory concentration (MIC) result against Gram-negative (G-ve, E. coli) and Gram-positive (G+ve, Bacillus cereus) bacteria with inhibition ratios of 80.7% and 75.5%, respectively. Nanocomposite-treated cells displayed complete lysis of the bacterial cell, a low amount of DNA, and cell membrane and wall disruption. Glutamate dehydrogenase (GDH) and malate dehydrogenase (MDH) activities of tested bacterial strains were demonstrated using spectrophotometry and electrophoresis on a non-denaturing acrylamide gel. In CS/AgNC-treated strains, enzyme production and activity were fewer than in untreated strains. The obtained results suggested that CS/AgNC seems to be more effective against G-ve than G+ve bacteria. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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