scholarly journals Scanning electron microscopy of biofilm formation by Staphylococcus aureus on stainless steel and polypropylene surfaces

2014 ◽  
Vol 8 (34) ◽  
pp. 3136-3143
Author(s):  
Alessandra P. Sant’Anna Salimena ◽  
◽  
Alexandre C. Santos ◽  
Maria das Graças Cardoso ◽  
Eduardo Alves ◽  
...  
2020 ◽  
Vol 20 (24) ◽  
pp. 2186-2191
Author(s):  
Lialyz Soares Pereira André ◽  
Renata Freire Alves Pereira ◽  
Felipe Ramos Pinheiro ◽  
Aislan Cristina Rheder Fagundes Pascoal ◽  
Vitor Francisco Ferreira ◽  
...  

Background: Resistance to antimicrobial agents is a major public health problem, being Staphylococcus aureus prevalent in infections in hospital and community environments and, admittedly, related to biofilm formation in biotic and abiotic surfaces. Biofilms form a complex and structured community of microorganisms surrounded by an extracellular matrix adhering to each other and to a surface that gives them even more protection from and resistance against the action of antimicrobial agents, as well as against host defenses. Methods: Aiming to control and solve these problems, our study sought to evaluate the action of 1,2,3- triazoles against a Staphylococcus aureus isolate in planktonic and in the biofilm form, evaluating the activity of this triazole through Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) tests. We have also performed cytotoxic evaluation and Scanning Electron Microscopy (SEM) of the biofilms under the treatment of the compound. The 1,2,3-triazole DAN 49 showed bacteriostatic and bactericidal activity (MIC and MBC 128 μg/mL). In addition, its presence interfered with the biofilm formation stage (1/2 MIC, p <0.000001) and demonstrated an effect on young preformed biofilm (2 MICs, p <0.05). Results: Scanning Electron Microscopy images showed a reduction in the cell population and the appearance of deformations on the surface of some bacteria in the biofilm under treatment with the compound. Conclusion: Therefore, it was possible to conclude the promising anti-biofilm potential of 1,2,3-triazole, demonstrating the importance of the synthesis of new compounds with biological activity.


2010 ◽  
Vol 55 (3) ◽  
pp. 1021-1027 ◽  
Author(s):  
Mei-Hui Lin ◽  
Fang-Rong Chang ◽  
Mu-Yi Hua ◽  
Yang-Chang Wu ◽  
Shih-Tung Liu

ABSTRACT1,2,3,4,6-Penta-O-galloyl-β-d-glucopyranose (PGG) is an active ingredient in plants that are commonly used in Chinese medicine to treat inflammation. We demonstrate here that PGG, at 6.25 μM, does not inhibit the growth ofStaphylococcus aureus, and yet it prevents biofilm formation on polystyrene and polycarbonate surfaces. At the same concentration, PGG is not toxic to human epithelial and fibroblast cells. PGG has an IB50value, i.e., the PGG concentration that inhibits 50% biofilm formation, of 3.6 μM. The value is substantially lower than that ofN-acetylcysteine, iodoacetamide, andN-phenyl maleimide, which are known to inhibit biofilm formation byS. aureus. Biochemical and scanning electron microscopy results also reveal that PGG inhibits initial attachment of the bacteria to solid surface and the synthesis of polysaccharide intercellular adhesin, explaining how PGG inhibits biofilm formation. The results of this study demonstrate that coating PGG on polystyrene and silicon rubber surfaces with polyaniline prevents biofilm formation, indicating that PGG is highly promising for clinical use in preventing biofilm formation byS. aureus.


2005 ◽  
Vol 68 (1) ◽  
pp. 92-97 ◽  
Author(s):  
ANDREW G. MOLTZ ◽  
SCOTT E. MARTIN

Eight strains of Listeria monocytogenes (7644, 19112, 15313, Scott A, LCDC, 10403S, SLCC, and 1370) produce biofilms when grown on polyvinyl chloride microtiter well plates. The growth medium (tryptic soy broth [TSB] or modified Welshimer's broth [MWB] at 32°C) influenced the amount of biofilm formed; maximum biofilms were formed in MWB by six strains and in TSB by the remaining two strains. This result suggests that the growth medium is critical in development of L. monocytogenes biofilm. This organism also produced biofilms on stainless steel chips. Biofilm formation on these chips was observed following growth in TSB at 4, 20, and 37°C. After 20 h of incubation at 20 or 37°C, the cell density was approximately 106 CFU per chip, and after 4 days incubation at 4°C, the cell density was 105 CFU per chip. L. monocytogenes strain Scott A biofilm formation on stainless steel chips was visualized using scanning electron microscopy, which revealed dense aggregates of cells held together by meshlike webbing.


1988 ◽  
Vol 71 (5) ◽  
pp. 868-871
Author(s):  
Edith M Alfano ◽  
Eugene C Cole ◽  
William A Rut Ala

Abstract Stainless steel penicylinders inoculated separately with test bacteria {Salmonella choleraesuis, Pseudomonas aeruginosa, or Staphylococcus aureus) are used in the AOAC use-dilution method (UDM) for disinfectant efficacy testing. Numbers of bacteria remaining on penicylinders were quantitatively assessed to determine if cells are washed from the penicylinders after a 10 min exposure to phosphate buffer dilution water (PBDW). Inoculated penicylinders were also examined by scanning electron microscopy (SEM) to determine the presence of cells remaining attached to the penicylinders after a 10 min exposure to a quaternary ammonium disinfectant and separately to PBDW. The percentage of cells washed from inoculated penicylinders exposed to PBDW was 89.9 for Salmonella choleraesuis, 48.8 for Pseudomonas aeruginosa, and 38.8 for Staphylococcus aureus. Qualitative examination of penicylinders by scanning electron microscopy confirmed the attachment of S. aureus and P. aeruginosa cells to penicylinders exposed separately to PBDW and a quaternary ammonium disinfectant. Few S. choleraesuis cells were observed on penicylinders exposed to PBDW and no cells were observed after disinfectant exposure. The variability of the numbers of viable cells entering the recovery media among the 3 UDM test bacteria due to cell detachment could be a significant factor in the recognized variability of the use-dilution method.


2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Agostinho Alves de Lima e Silva ◽  
Alice Slotfeldt Viana ◽  
Priscila Martins Silva ◽  
Eduardo de Matos Nogueira ◽  
Leonardo Tavares Salgado ◽  
...  

Staphylococcus aureus is a pathogen commonly resistant to antibiotics. Biofilm formation is one of the important factors related to its virulence. Non-antibiotics drugs, such as nonsteroidal anti-inflammatory agents (NSAIDs), have been studied as an alternative for treating infections by multiresistant pathogens and biofilm-associated infections. In this study, the effects of NSAID sodium diclofenac on growth inhibition and biofilm formation of S. aureus were evaluated. The minimum inhibitory concentration (MIC) of diclofenac for fifty isolates ranged from 200 to 400 μg/mL. Diclofenac sub-MICs induced biofilm in 32.3% of biofilm-negative strains in tryptic soy broth. All biofilms induced by the drug showed a PIA- (polysaccharide intercellular adhesion-) independent composition, and the scanning electron microscopy showed that the induced biofilm presented a very discrete matrix. The combination of diclofenac with rifampicin sub-MICs induced strong production of PIA-dependent biofilm in three of four strains, while combination of NSAID with NaCl induced the formation of partially polysaccharide biofilm in two strains and PIA-independent biofilm in another strain. The combination of NSAID with glucose resulted in PIA-independent biofilms in all four strains tested. The results showed that diclofenac can commonly induce biofilm production by a PIA-independent pathway. However, when this NSAID is combined with other types of inducing agents, the composition of the biofilm produced may vary.


2019 ◽  
Vol 67 (10) ◽  
pp. 1708
Author(s):  
Dipankar Das ◽  
Harsha Bhattacharjee ◽  
Krishna Gogoi ◽  
JayantaK Das ◽  
Puneet Misra ◽  
...  

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Heriyanto Tinentang ◽  
Henry F Aritonang ◽  
Harry S. J. Koleangan

Telah dilakukan penelitian tentang kemampuan aktivitas anti bakteri untuk bakteri Staphylococcus aureus (gram positif) dan Escherichia coli (gram negatif) dengan menggunakan nanokomposit nata de coco/TiO2, nata de coco/Ag, dan nata de coco/TiO2/Ag dengan variasi konsentrasi Ag 0,5 M; 0,6 M; 0,7 M; 0,8 M dan 0,9 M  menggunakan metode reduksi kimia. Nanopartikel tersebut dikarakterisasi menggunakan X-Ray Diffractometry (XRD), scanning electron microscopy-energy dispersive X-ray spectroscopy  (SEM-EDS) dan anti bakteri. Untuk uji aktivitas antibakteri menggunakan metode kertas cakram dan dilakukan sebanyak dua kali ulangan untuk tiap-tiap sampel dan bakteri yang diuji. Hasil penelitian menunjukan, aktivitas anti bakteri nanokomposit yang paling baik dalam menghambat pertumbuhan bakteri adalah nanokomposit Nata de coco/TiO2/Ag mampu menghambat pertumbuhan bakteri Escherichiacoli dan Staphylococcusaureus, namun nanokomposit tersebut lebih efektif menghambat pertumbuhan bakteri Escherichiacoli.ABSRACT Research on the ability of anti-bacterial activity for Staphylococcus aureus (gram positive) and Escherichia coli (gram negative) bacteria using nata de coco / nanocomposites TiO2, nata de coco / Ag, and nata de coco / TiO2 / Ag with variations of Ag 0,5 M; 0.6 M; 0.7 M; 0.8 M and 0.9 M using the chemical reduction method. Nanoparticles were characterized using X-Ray Diffractometry (XRD), scanning electron microscopy-energy dispersive X-ray spctroscopy  (SEM-EDS) and anti-bacterial actvity. Test the antibacterial activity using the paper disc method and repeated two times for each sample and bacteria tested. The results showed that the good anti-bacterial activity of nanocomposites in inhibiting bacterial growth was nanocomposite nata de coco /TiO2/Ag  able to inhibit the growth of Escherichia coli and S. aureus, but the nanocomposite is more effective in inhibiting the growth of Escherichia  coli bacteria.


2020 ◽  
Vol 8 (3) ◽  
pp. 71
Author(s):  
Masaaki Minami ◽  
Hiroshi Takase ◽  
Masayo Taira ◽  
Toshiaki Makino

Streptococcus mutans, a bacterium that causes dental plaques, forms a biofilm on tooth surfaces. This biofilm can cause gingivitis by stimulating the gingival margin. However, there is no established treatment for biofilm removal. Hainosan (Painongsan), a traditional Japanese Kampo formula, has been used to treat gingivitis. Therefore, we investigated the biofilm suppressive effects of the hainosan extract (HNS) and its components on S. mutans. We conducted scanning electron microscopy and confocal laser microscopy analyses to clarify the anti-biofilm activities of HNS and its crude drugs. We also performed a quantitative RT-PCR assay to assess the biofilm-related gene expression. HNS showed a significant dose-dependent suppressive effect on biofilm formation. Both the scanning electron microscopy and confocal laser microscopy analyses also revealed the significant inhibitory effects of the extract on biofilm formation. Transmission electron microscopy analysis showed that HNS disrupted the surface of the bacterial wall. Furthermore, HNS reduced the hydrophobicity of the bacteria, and suppressed the mRNA expression of β-glucosyltransferase (gtfB), glucosyltransferase-SI (gtfC), and fructosyltransferase (ftf). Among the constituents of hainosan, the extract of the root of Platycodon grandiflorum (PG) showed the strongest biofilm suppression effect. Platycodin D, one of the constituent natural compounds of PG, inhibited S. mutans-associated biofilm. These findings indicate that hainosan eliminates dental plaques by suppressing biofilm formation by S. mutans.


2011 ◽  
Vol 183-185 ◽  
pp. 1837-1841
Author(s):  
Lei Sha ◽  
Yan Lai Wang ◽  
Shi Liang Ban

CuInSe2 thin films were obtained by selenization of the Cu-In precursors in the atmosphere of Se vapour, which were prepared on stainless steel and titanium substrates by electrodeposition. The films were characterized by XRD, scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The respective influences of composition, phases and surface morphology of Cu-In precursors on indium loss were investigated. The results indicate that the indium loss occurs in selenization process because of volatile In2Se arising. The indium loss is less in selenization process of Cu-In precursors contained CuIn, Cu2In and In phases.


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