Atomic force microscopic study on morphological alterations induced by photodynamic action of Toluidine Blue O in Staphylococcus aureus and Escherichia coli

2009 ◽  
Vol 96 (1) ◽  
pp. 9-16 ◽  
Author(s):  
Khageswar Sahu ◽  
Harsha Bansal ◽  
Chandrachur Mukherjee ◽  
Mrinalini Sharma ◽  
Pradeep Kumar Gupta
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Microscopic Study ◽  
Toluidine Blue ◽  
Photodynamic Action ◽  
Morphological Alterations ◽  
Atomic Force

scholarly journals Cellulose Acetate Containing Toluidine Blue and Rose Bengal Is an Effective Antimicrobial Coating when Exposed to White Light

2006 ◽  
Vol 72 (6) ◽  
pp. 4436-4439 ◽  
Author(s):  
Val�rie Decraene ◽  
Jonathan Pratten ◽  
Michael Wilson
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Candida Albicans ◽  
Clostridium Difficile ◽  
Cellulose Acetate ◽  
Toluidine Blue ◽  
White Light ◽  
Rose Bengal ◽  
Microbial Load ◽  
Hospital Associated Infections

ABSTRACT Simple methods of reducing the microbial load on surfaces in hospitals are needed to reduce the risk of hospital-associated infections. Here we report on the ability of a cellulose acetate coating containing the photosensitizers toluidine blue and rose bengal to kill microbes (Staphylococcus aureus, Escherichia coli, Clostridium difficile, a bacteriophage, and Candida albicans) on its surface when illuminated with white light.

scholarly journals Photodynamic Therapy With Propolis: Antibacterial Effects on Staphylococcus aureus, Streptococcus mutans and Escherichia coli Analysed by Atomic Force Microscopy

2020 ◽  
Vol 11 (Suppl 1) ◽  
pp. S107-S112
Author(s):  
Alice de Morais Veras Fonseca ◽  
Guilherme Herbet Leite Sampaio ◽  
Wládia Pontes Araujo ◽  
Raí Emanuel Silva ◽  
Fábio de Oliveira Silva Ribeiro ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Atomic Force Microscopy ◽  
Photodynamic Therapy ◽  
Streptococcus Mutans ◽  
Antibacterial Effects ◽  
Force Microscopy ◽  
Atomic Force

scholarly journals Sustainable Coated Nanostructures Based on Alginate and Electrospun Collagen Loaded with Antimicrobial Agents

Coatings ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 121
Author(s):  
Ecaterina Matei ◽  
Carmen Gaidau ◽  
Maria Râpă ◽  
Laura Mihaela Stefan ◽  
Lia-Mara Ditu ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Antimicrobial Agents ◽  
Biological Properties ◽  
Wound Dressings ◽  
Bacterial Strains ◽  
Force Microscopy ◽  
Atomic Force ◽  
Nanostructured Systems

In this study, sodium alginate film (Alg) was coated with electrospun collagen glue (Col) extracted from rabbit skin waste, loaded with different commercial antimicrobial agents (chitosan, AG425K and ZnONPs) and investigated in terms of morphological, structural and biological properties. The coated nanostructures were characterized using scanning electron microscopy coupled with the energy-dispersive X-ray (SEM/EDS), Attenuated Total Reflectance Fourier-Transform Infrared spectroscopy (ATR FT-IR), and Atomic Force Microscopy (AFM) tests. The cytotoxicity was investigated on murine L929 fibroblasts using 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide salt (MTT) and lactate dehydrogenase (LDH) assays. Microbiological tests were performed against Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853 and Candida albicans ATCC 27853 standard strains. In vitro cell culture tests showed a good cytocompatibility of the coated nanostructured systems, except the sample loaded with ZnONPs, which exhibited a highly cytotoxic effect. Alg-Col-ZnONPs nanostructure inhibited the growth and multiplication of the Staphylococcus aureus ATCC 25923 and Escherichia coli ATCC 25922 bacterial strains. The results of new coated nanostructures may be useful for the development of sustainable biomaterials in a circular economy, with bioactive properties for medical wound dressings.

scholarly journals Atomic Force Microscopy: Application to Investigation of Escherichia coli Morphology before and after Exposure to Cefodizime

1998 ◽  
Vol 42 (1) ◽  
pp. 18-22 ◽  
Author(s):  
Pier Carlo Braga ◽  
Davide Ricci
Keyword(s):  
Escherichia Coli ◽  
Atomic Force Microscopy ◽  
Biological Fluids ◽  
Metal Layer ◽  
Near Field ◽  
Beta Lactam ◽  
Morphological Alterations ◽  
Bacterial Surface ◽  
Force Microscopy ◽  
Atomic Force

ABSTRACT Atomic force microscopy (AFM) is a recently developed technique that allows for the investigation of the surface morphology of a biological specimen at an unprecedented level of resolution. The aim of the present study was to explore some of the new opportunities offered by AFM by studying the morphological and surface alterations induced inEscherichia coli by supra-MICs and sub-MICs of a beta-lactam antibiotic (cefodizime). The underlying principle of AFM is the scanning and sensing of the topography of a sample by means of near-field microscopy that makes it possible to obtain simultaneous digital measurements of the x, y, andz coordinates of any point on the bacterial surface with great resolution (x andy, ∼20 Å; z, ∼1 Å). Unlike scanning electron microscopy, performance of AFM does not require a vacuum, drying to the critical point, or the coating of the bacterial surface with a metal layer. The digital storage of the information makes it easy to rotate the image, observe the bacterial surface and induced structural alterations from different points of view, and obtain a cross-section at any desired point with precise, automatic measurement of the heights and sizes of normal versus damaged bacteria. Use of the new and outstanding technique of AFM will make it possible for researchers to investigate biological samples immersed in biological fluids and will also make it possible for them to study the morphological alterations of living bacteria exposed to antibiotics as they are taking place.

Antimicrobial and cytotoxic activity of Macrophomina phaseolina isolated from gummosis infected citrus reticulata

2013 ◽  
pp. 125-133
Author(s):  
Rubal C Das ◽  
Rajib Banik ◽  
Robiul Hasan Bhuiyan ◽  
Md Golam Kabir
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Brine Shrimp ◽  
Inhibitory Concentration ◽  
Lethal Dose ◽  
Macrophomina Phaseolina ◽  
Chloroform Extract ◽  
Citrus Reticulata ◽  
Gram Negative Bacteria ◽  
Gram Negative

Macrophomina phaseolina is one of the pathogenic organisms of gummosis disease of orange tree (Citrus reticulata). The pathogen was identified from the observation of their colony size, shape, colour, mycelium, conidiophore, conidia, hyaline, spore, and appressoria in the PDA culture. The crude chloroform extracts from the organism showed antibacterial activity against a number of Gram positive and Gram-negative bacteria. The crude chloroform extract also showed promising antifungal activity against three species of the genus Aspergillus. The minimum inhibitory concentration (MIC) of the crude chloroform extract from M. phaseolina against Bacillus subtilis, Staphylococcus aureus, Escherichia coli, and Shigella sonnie were 128 ?gm, 256 ?gm, 128 ?gm and 64 ?gm/ml respectively. The LD50 (lethal dose) values of the cytotoxicity assay over brine shrimp of the crude chloroform extract from M. phaseolina was found to be 51.79 ?gm/ml. DOI: http://dx.doi.org/10.3329/cujbs.v5i1.13378 The Chittagong Univ. J. B. Sci.,Vol. 5(1 &2):125-133, 2010

Screening and antimicrobial activity of actinomycetes isolated from the rhizosphere of Clitoria ternatea

2016 ◽  
Vol 1 (01) ◽  
Author(s):  
Vemavarapu Bhaskara Rao ◽  
Kandlagunta Guru Prasad ◽  
Krishna Naragani ◽  
Vijayalakshmi Muvva
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Antimicrobial Activity ◽  
Candida Albicans ◽  
Calcium Carbonate ◽  
Rhizosphere Soil ◽  
Soil Samples ◽  
Antimicrobial Spectrum ◽  
Clitoria Ternatea ◽  
Primary Screening

The air dried rhizosphere soil samples pretreated with calcium carbonate was employed for the isolation of actinomycete strains. Serial dilution plate technique was used for the isolation of actinomycetes. A total of 20 actinomycete strains designated as BS1-BS20 were isolated from the rhizosphere of medicinal plant Clitoria ternatea. All the 20 strains were subjected to primary screening for antimicrobial activity. Among the 20 strains screened, 10 strains exhibited high antimicrobial spectrum against Staphylococcus aureus, Escherichia coli and Candida albicans.

Synthesis, photosensitization and antimicrobial activity evaluation of some novel Merocyanine dyes

2019 ◽  
Author(s):  
Chem Int
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Antimicrobial Activity ◽  
Aspergillus Flavus ◽  
Elemental Analysis ◽  
Cyanine Dyes ◽  
Fungal Strains ◽  
Activity Evaluation ◽  
Visible Spectra ◽  
Merocyanine Dyes

Novel acyclic and cyclic merocyanine dyes derived from the nucleu of furo [(3,2-d) pyrazole; ( d 2 , 3 )imidazole]were prepared. The electronic visible absorptionspectra of all the synthesized new cyanine dyes were examined in 95% ethanolsolution to evaluate their photosensitization properties. Antibacterial andantifungal activities for some selected dyes were tested against various bacterialand fungal strains (Escherichia coli, Staphylococcus aureus, Aspergillus flavus andCandida albicans) to evaluate their antimicrobial activity. Structural identificationwas carried out via elemental analysis, visible spectra, IR and 1H NMRspectroscopic data.

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