scholarly journals Effect of a Silver Nanoparticles Solution onStaphylococcus aureusandCandidaspp.

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Amanda Fucci Wady ◽  
Ana Lucia Machado ◽  
Camila Cristina Foggi ◽  
Camila Andrade Zamperini ◽  
Valtencir Zucolotto ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Antimicrobial Activity ◽  
Candida Glabrata ◽  
Morphological Changes ◽  
Chemical Reduction ◽  
Total Biomass ◽  
Systemic Diseases ◽  
Planktonic Cells ◽  
Sem Images ◽  
Scanning Electron

An AgNPs solution was synthesized by chemical reduction, characterized, and tested againstCandida glabrata,Candida tropicalis,Staphylococcus aureus, and methicillin-resistantStaphylococcus aureus(MRSA). Minimum inhibitory (MICs) and minimum fungicidal/bactericidal concentrations (MFC/MBC) were determined on planktonic cells. Also, total biofilm mass was determined by crystal violet (CV) staining and morphological changes by scanning electron microscope (SEM). MICs forC. glabrata,C. tropicalis,S. aureus, and MRSA were 15.63, 3.91, 1.95, and 1.95 µg/mL, respectively. MFC forC. glabratawas 62.5 µg/mL and forC. tropicalis15.63 µg/mL The same MBC (3.91 µg/mL) was observed forS. aureusand MRSA. CV assay showed that the AgNPs (1000 μg/mL) promoted reductions in biofilm mass of ~60% forC. glabrataand ~35% forC. tropicalis. A reduction of ~20% inC. tropicalisbiomass was also observed at the concentration of 3.91 µg/mL. No significant effect on total biomass was found forS. aureusand MRSA. SEM images revealed thatC. glabrataandC. tropicalisbiofilm cells, exposed to the AgNPs (1000 μg/mL), had an irregular and shriveled appearance. AgNPs solution exhibited considerable antimicrobial activity against important fungal and bacterial pathogens, associated with several oral and systemic diseases, and has potential as an antimicrobial agent.

scholarly journals SINTESIS NANOKOMPOSIT Nata de coco/TiO2/Ag DAN EFEKTIVITASNYA SEBAGAI ANTIBAKTERI TERHADAP BAKTERI Escherichia coli dan Staphylococcus aureus

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Heriyanto Tinentang ◽  
Henry F Aritonang ◽  
Harry S. J. Koleangan
Keyword(s):  
Electron Microscopy ◽  
Escherichia Coli ◽  
Scanning Electron Microscopy ◽  
Staphylococcus Aureus ◽  
Chemical Reduction ◽  
Bacterial Activity ◽  
Energy Dispersive ◽  
X Ray ◽  
Escherichia Coli Bacteria ◽  
Scanning Electron

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.

scholarly journals Ultrastructural Study of Elaeis guineensis (Oil Palm) Leaf and Antimicrobial Activity of its Methanol Extract against Staphylococcus Aureus

2016 ◽  
Vol 12 (3) ◽  
pp. 419-423 ◽  
Author(s):  
Amala Rajoo ◽  
Sreenivasan Sasidharan ◽  
Subramanion L Jothy ◽  
Surash Ramanathan ◽  
Sharif M Mansor
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Staphylococcus Aureus ◽  
Transmission Electron Microscopy ◽  
Antimicrobial Activity ◽  
Methanol Extract ◽  
Elaeis Guineensis ◽  
Transmission Electron ◽  
Inhibition Concentration ◽  
Scanning Electron

Purpose: To evaluate the antimicrobial activity of the methanol extract of Elaeis guineensis leaf against Staphylococcus aureus and to determine the effect of extract treatment on the microstructure of the microbeMethods: The antimicrobial activity of the methanol leaf extract of the plant against S. aureus was examined using disc diffusion and broth dilution methods. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were carried out to determine the major alterations in the microstructure of S. aureus after treatment with the extract.Results: The extract showed a good antimicrobial activity against S. aureus with a minimum inhibition concentration (MIC) of 6.25 mg/mL and for Chloramphenicol was 30.00 ìg/mL. The main changes observed under SEM and TEM were structural disorganization of the cell membrane which occurred after 12 h and total collapse of the cell 36 h after exposure to the extract.Conclusion: We concluded that the methanolic extract of E. guineensis leaf exhibited good antimicrobial activity against S. aureus and this is supported by SEM and TEM.Keywords: Antimicrobial activity, Elaeis guineensis, Staphylococcus aureus, Scanning electron microscopy, Transmission electron microscopy

Assembly and antifungal effect of a new fluconazole-carrier nanosystem

2020 ◽  
Vol 15 (4) ◽  
pp. 273-285 ◽  
Author(s):  
Taynara MT de Lima ◽  
Laís S Arias ◽  
Letícia F Afanaci ◽  
Raphael FB Ferraresse ◽  
Francisco N de S Neto ◽  
...  
Keyword(s):  
Minimum Inhibitory Concentration ◽  
Candida Glabrata ◽  
Inhibitory Concentration ◽  
Fungal Infections ◽  
Oxide Nanoparticles ◽  
Total Biomass ◽  
Planktonic Cells ◽  
Antifungal Effect ◽  
Concentration Determination ◽  
Antifungal Effects

Aim: To assemble, characterize and assess the antifungal effects of a new fluconazole (FLZ)-carrier nanosystem. Materials & methods: The nanosystem was prepared by loading FLZ on chitosan (CS)-coated iron oxide nanoparticles (IONPs). Antifungal effects were evaluated on planktonic cells (by minimum inhibitory concentration determination) and on biofilms (by quantification of cultivable cells, total biomass, metabolism and extracellular matrix) of Candida albicans and Candida glabrata. Results: Characterization results ratified the formation of a nanosystem (<320 nm) with FLZ successfully embedded. IONPs-CS-FLZ nanosystem reduced minimum inhibitory concentration values and, in general, showed similar antibiofilm effects compared with FLZ alone. Conclusion: IONPs-CS-FLZ nanosystem was more effective than FLZ mainly in inhibiting Candida planktonic cells. This nanocarrier has potential to fight fungal infections.

Antimicrobial Activity of Extracts of the Lichen Xanthoparmelia pokornyi and its Gyrophoric and Stenosporic Acid Constituents

2006 ◽  
Vol 61 (5-6) ◽  
pp. 319-323 ◽  
Author(s):  
Mehmet Candan ◽  
Meral Yılmaz ◽  
Turgay Tay ◽  
Merih Kıvança ◽  
Hayrettin Türk
Keyword(s):  
Staphylococcus Aureus ◽  
Antimicrobial Activity ◽  
Bacillus Subtilis ◽  
Candida Albicans ◽  
Aeromonas Hydrophila ◽  
Candida Glabrata ◽  
Proteus Vulgaris ◽  
Ethanol Extracts ◽  
Bacteria And Fungi ◽  
Gyrophoric Acid

The antimicrobial activity of the diethyl ether, acetone, chloroform, petroleum ether, and ethanol extracts of the lichen Xanthoparmelia pokornyi and its gyrophoric acid and stenosporic acid constituents has been screened against some foodborne bacteria and fungi. Both the extracts and the acids showed antimicrobial activity against Aeromonas hydrophila, Bacillus cereus, Bacillus subtilis, Listeria monocytogenes, Proteus vulgaris, Staphylococcus aureus, Streptococcus faecalis, Yersinia enterocolitica, Candida albicans and Candida glabrata. The extracts were inactive against the tested filamentous fungi. The MIC values of the extracts and the acids for the bacteria have also been determined.

Evaluation of the Antimicrobial Activity of the Acetone Extract of the Lichen Ramalina farinacea and its (+)-Usnic Acid, Norstictic Acid, and Protocetraric Acid Constituents

2004 ◽  
Vol 59 (5-6) ◽  
pp. 384-388 ◽  
Author(s):  
Turgay Tay ◽  
Ayşen Özdemir Türk ◽  
Meral Yılmaz ◽  
Hayrettin Türk ◽  
Merih Kıvanç
Keyword(s):  
Staphylococcus Aureus ◽  
Antimicrobial Activity ◽  
Bacillus Subtilis ◽  
Candida Albicans ◽  
Yersinia Enterocolitica ◽  
Aeromonas Hydrophila ◽  
Candida Glabrata ◽  
Usnic Acid ◽  
Acetone Extract ◽  
Ramalina Farinacea

The acetone extract of the lichen Ramalina farinacea and its (+)-usnic acid constituent showed antimicrobial activity against Bacillus subtilis, Listeria monocytogenes, Proteus vul­garis, Staphylococcus aureus, Streptococcus faecalis. Yersinia enterocolitica, Candida albicans, and Candida glabrata. Norstictic acid was active against Aeromonas hydrophila as well as the above microorganisms except Yersinia enterocolitica. Protocetraric acid showed activity only against the tested yeasts Candida albicans and Candida glabrata. The MIC values of the extract as well as of the three substances were determined. No antifungal activity of the acetone extract has been observed against ten filamentous fungi.

Antimicrobial Activity of Galangin and Its Effects on Murein Hydrolases of Vancomycin-Intermediate Staphylococcus aureus (VISA) Strain Mu50

Chemotherapy ◽  
2017 ◽  
Vol 63 (1) ◽  
pp. 20-28 ◽  
Author(s):  
Jing Ouyang ◽  
Fengjun Sun ◽  
Wei Feng ◽  
Yonghong Xie ◽  
Lijuan Ren ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Antimicrobial Activity ◽  
Cell Wall ◽  
Morphological Changes ◽  
Control Group ◽  
Cellular Division ◽  
Murein Hydrolase ◽  
Triton X ◽  
Cell Wall Hydrolysis ◽  
Induced Autolysis

Backgroud: Antibiotic treatment for infections caused by vancomycin-intermediate Staphylococcus aureus (VISA) strains is challenging, and only a few effective and curative methods have been developed to combat these strains. This study aimed to investigate the antimicrobial activity of galangin against S. aureus and its effects on the murein hydrolases of VISA strain Mu50. This is the first report on these effects of galangin, and it may help to improve the treatment for VISA infections by demonstrating the effective use of galangin. Methods: Firstly, the minimum inhibitory concentration (MIC) and growth curve were used to investigate the antimicrobial activity of galangin against S. aureus. Secondly, transmission electron microscopy (TEM) was used to observe morphological changes of VISA strain Mu50. Thirdly, Triton X-100-induced autolysis and cell wall hydrolysis assays were performed to determine the activities of the murein hydrolases of Mu50. Finally, fluorescence real-time quantitative PCR was used to investigate the expression of the murein hydrolase-related Mu50 genes. Results: The results indicated that the MIC of galangin was 32 μg/mL against ATCC25293, N315, and Mu50, and galangin could significantly suppress the bacterial growth (p < 0.05) with concentrations of 4, 8 and 16 μg/mL, compared with control group (0 μg/mL). To explore the possible reasons of bacteriostatic effects of galangin, we observed morphological changes using TEM which showed that the division of Mu50 daughter cells treated with galangin was obviously inhibited. Considering the vital role of murein hydrolases in cellular division, assays were performed, and galangin markedly decreased Triton X-100-induced autolysis and cell wall hydrolysis. Galangin also significantly inhibited the expression of the murein hydrolase genes (atl, lytM, and lytN) and their regulatory genes (cidR, cidA, and cidB). Conclusions: Our findings indicated that galangin can effectively inhibit murein hydrolase activity as well as the growth of VISA strain Mu50.

scholarly journals Co0 superparamagnetic nanoparticles stabilized by an organic layer coating with antimicrobial activity

RSC Advances ◽  
2020 ◽  
Vol 10 (57) ◽  
pp. 34712-34718 ◽  
Author(s):  
Paula A. Santana ◽  
Carolina A. Castillo ◽  
Sebastián A. Michea ◽  
Diego Venegas-Yazigi ◽  
Verónica Paredes-García
Keyword(s):  
Staphylococcus Aureus ◽  
Antimicrobial Activity ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Solvothermal Synthesis ◽  
Superparamagnetic Nanoparticles ◽  
Organic Layer ◽  
Layer Coating ◽  
Scanning Electron

The Co0@C-NPs were obtained using solvothermal synthesis. The Co0@C-NPs were characterized by different techniques and its antimicrobial activity was assessed against Staphylococcus aureus by microdilution assay and scanning electron microscope.

scholarly journals Analysis of Polyphenolic Compounds in Extracts from Leaves of SomeMalus domesticaCultivars: Antiradical and Antimicrobial Analysis of These Extracts

2016 ◽  
Vol 2016 ◽  
pp. 1-12 ◽  
Author(s):  
Alina Sowa ◽  
Grażyna Zgórka ◽  
Aleksandra Szykuła ◽  
Roman Franiczek ◽  
Beata Żbikowska ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Antimicrobial Activity ◽  
Ethyl Acetate ◽  
Candida Glabrata ◽  
Antiradical Activity ◽  
Colorimetric Method ◽  
Water Extract ◽  
Diffusion Method ◽  
Strong Activity ◽  
Ethyl Acetate Extracts

In this study, methanol, ethyl acetate, water extracts, and precipitate were obtained from leaves ofMalus domesticacultivars: Golden delicious, Jonagold, Elstar, Ligol, and Mutsu. Antiradical activity of these extracts was measured using theABTS+∙radical, and antimicrobial activity was measured with the disk-diffusion method. Phenolic compounds were measured with the colorimetric method and identified with high performance liquid chromatography (HPLC). The highest antiradical activity was observed for the Jonagold variety, and in particular strong activity was noted for ethyl acetate extracts. Antimicrobial activity was observed against strains ofStaphylococcus aureus,Enterococcus faecalis, and the fungusCandida glabrata. Particularly susceptible to the extracts activity appeared to beStaphylococcus aureus, but the growth ofCandida glabratawas inhibited in the presence of ethyl acetate extracts. With the HPLC method we identified a high amount of phloridzin (above 500 mg per g of ethyl acetate extracts), lower amounts of hyperoside, isoquercitrin, and quercitrin, and traces ofp-hydroxybenzoic and chlorogenic acids. The contribution of phloridzin to antiradical activity of methanol and ethyl acetate extracts was very high (above 90%). In water extract the contribution of phloridzin was between 38.9 and 55.2%, chlorogenic acid 22.7 and 36.1%, and hyperoside 12.2 and 13.3%.

scholarly journals Multisubstituted pyrimidines effectively inhibit bacterial growth and biofilm formation of Staphylococcus aureus

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Riccardo Provenzani ◽  
Paola San-Martin-Galindo ◽  
Ghada Hassan ◽  
Ashenafi Legehar ◽  
Aleksi Kallio ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Biofilm Formation ◽  
Inhibitory Concentration ◽  
Total Biomass ◽  
Dependent Manner ◽  
Planktonic Cells ◽  
Concentration Dependent Manner ◽  
New Chemical Entities ◽  
Viable Bacteria ◽  
Conventional Antibiotics

AbstractBiofilms are multicellular communities of microorganisms that generally attach to surfaces in a self-produced matrix. Unlike planktonic cells, biofilms can withstand conventional antibiotics, causing significant challenges in the healthcare system. Currently, new chemical entities are urgently needed to develop novel anti-biofilm agents. In this study, we designed and synthesized a set of 2,4,5,6-tetrasubstituted pyrimidines and assessed their antibacterial activity against planktonic cells and biofilms formed by Staphylococcus aureus. Compounds 9e, 10d, and 10e displayed potent activity for inhibiting the onset of biofilm formation as well as for killing pre-formed biofilms of S. aureus ATCC 25923 and Newman strains, with half-maximal inhibitory concentration (IC50) values ranging from 11.6 to 62.0 µM. These pyrimidines, at 100 µM, not only decreased the number of viable bacteria within the pre-formed biofilm by 2–3 log10 but also reduced the amount of total biomass by 30–50%. Furthermore, these compounds were effective against planktonic cells with minimum inhibitory concentration (MIC) values lower than 60 µM for both staphylococcal strains. Compound 10d inhibited the growth of S. aureus ATCC 25923 in a concentration-dependent manner and displayed a bactericidal anti-staphylococcal activity. Taken together, our study highlights the value of multisubstituted pyrimidines to develop novel anti-biofilm agents.

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