Silver nanoparticles (Ag-NPs) can be considered as a cost-effective alternative to antibiotics. In the presence of Fe(III)-citrate and Ag+, Klebsiella oxytoca DSM 29614 produces biogenic Ag-NPs embedded in its peculiar exopolysaccharide (EPS). K. oxytoca DSM 29614 was cultivated in a defined growth medium–containing citrate (as sole carbon source) and supplemented with Ag+ and either low or high Fe(III) concentration. As inferred from elemental analysis, transmission and scanning electron microscopy, Fourier transform infrared spectrometry and dynamic light scattering, Ag-EPS NPs were produced in both conditions and contained also Fe. The production yield of high-Fe/Ag-EPS NPs was 12 times higher than the production yield of low-Fe/Ag-EPS NPs, confirming the stimulatory effect of iron. However, relative Ag content and Ag+ ion release were higher in low-Fe/Ag-EPS NPs than in high-Fe/Ag-EPS NPs, as revealed by emission-excitation spectra by luminescent spectrometry using a novel ad hoc established phycoerythrin fluorescence–based assay. Interestingly, high and low-Fe/Ag-EPS NPs showed different and growth medium–dependent minimal inhibitory concentrations against Staphylococcus aureus ATCC 29213 and Pseudomonas aeruginosa ATCC 15442. In addition, low-Fe/Ag-EPS NPs exert inhibition of staphylococcal and pseudomonal biofilm formation, while high-Fe/Ag-EPS NPs inhibits staphylococcal biofilm formation only. Altogether, these results, highlighting the different capability of Ag+ release, support the idea that Fe/Ag-EPS NPs produced by K. oxytoca DSM 29614 can be considered as promising candidates in the development of specific antibacterial and anti-biofilm agents. Key points • Klebsiella oxytoca DSM 29614 produces bimetal nanoparticles containing Fe and Ag. • Fe concentration in growth medium affects nanoparticle yield and composition. • Phycoerythrin fluorescence–based assay was developed to determine Ag+release. • Antimicrobial efficacy of bimetal nanoparticle parallels Ag+ions release.
Cusimano M.G., Ardizzone F., Nasillo G., Gallo M., Sfriso A., Chillura Martino D., et al. (2020). Biogenic iron-silver nanoparticles inhibit bacterial biofilm formation due to Ag+ release as determined by a novel phycoerythrin-based assay. APPLIED MICROBIOLOGY AND BIOTECHNOLOGY, 104(14), 6325-6336.
Data di pubblicazione: | 2020 |
Titolo: | Biogenic iron-silver nanoparticles inhibit bacterial biofilm formation due to Ag+ release as determined by a novel phycoerythrin-based assay |
Autori: | GALLO, Giuseppe (Corresponding) |
Citazione: | Cusimano M.G., Ardizzone F., Nasillo G., Gallo M., Sfriso A., Chillura Martino D., et al. (2020). Biogenic iron-silver nanoparticles inhibit bacterial biofilm formation due to Ag+ release as determined by a novel phycoerythrin-based assay. APPLIED MICROBIOLOGY AND BIOTECHNOLOGY, 104(14), 6325-6336. |
Rivista: | |
Digital Object Identifier (DOI): | http://dx.doi.org/10.1007/s00253-020-10686-w |
Abstract: | Silver nanoparticles (Ag-NPs) can be considered as a cost-effective alternative to antibiotics. In the presence of Fe(III)-citrate and Ag+, Klebsiella oxytoca DSM 29614 produces biogenic Ag-NPs embedded in its peculiar exopolysaccharide (EPS). K. oxytoca DSM 29614 was cultivated in a defined growth medium–containing citrate (as sole carbon source) and supplemented with Ag+ and either low or high Fe(III) concentration. As inferred from elemental analysis, transmission and scanning electron microscopy, Fourier transform infrared spectrometry and dynamic light scattering, Ag-EPS NPs were produced in both conditions and contained also Fe. The production yield of high-Fe/Ag-EPS NPs was 12 times higher than the production yield of low-Fe/Ag-EPS NPs, confirming the stimulatory effect of iron. However, relative Ag content and Ag+ ion release were higher in low-Fe/Ag-EPS NPs than in high-Fe/Ag-EPS NPs, as revealed by emission-excitation spectra by luminescent spectrometry using a novel ad hoc established phycoerythrin fluorescence–based assay. Interestingly, high and low-Fe/Ag-EPS NPs showed different and growth medium–dependent minimal inhibitory concentrations against Staphylococcus aureus ATCC 29213 and Pseudomonas aeruginosa ATCC 15442. In addition, low-Fe/Ag-EPS NPs exert inhibition of staphylococcal and pseudomonal biofilm formation, while high-Fe/Ag-EPS NPs inhibits staphylococcal biofilm formation only. Altogether, these results, highlighting the different capability of Ag+ release, support the idea that Fe/Ag-EPS NPs produced by K. oxytoca DSM 29614 can be considered as promising candidates in the development of specific antibacterial and anti-biofilm agents. Key points • Klebsiella oxytoca DSM 29614 produces bimetal nanoparticles containing Fe and Ag. • Fe concentration in growth medium affects nanoparticle yield and composition. • Phycoerythrin fluorescence–based assay was developed to determine Ag+release. • Antimicrobial efficacy of bimetal nanoparticle parallels Ag+ions release. |
Appare nelle tipologie: | 1.01 Articolo in rivista |
File in questo prodotto:
File | Descrizione | Tipologia | Licenza | |
---|---|---|---|---|
Cusimano2020_Article_BiogenicIron-silverNanoparticle.pdf | Articolo principale | Versione Editoriale | Administrator Richiedi una copia |