A comparative study of three different viability tests for chemically or thermally inactivated Escherichia coli

Park, Seon Yeong; Kim, Chang Gyun

doi:10.4491/eer.2017.223

Cited by 17 publications

(10 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A variety of dye concentrations, dye incubation times, bacterial strains, growth and staining media, and excitation and emission wavelengths have been used with mixed results (Prakash Singh, 2006; Berney et al, 2007; Hoerr et al, 2007; Kort et al, 2010; Thomas et al, 2011; Eberhart et al, 2012; Freire et al, 2015; Stiefel et al, 2015; Park and Kim, 2018). A majority of the studies have followed the BacLight Kit instructions – growth of cells in rich media and washing in saline before staining, establishment of live and dead cell suspensions to generate a standard curve, and calculation of the red to green fluorescence ratio to determine the proportion of live cells in a sample (Prakash Singh, 2006; Hoerr et al, 2007; Eberhart et al, 2012; Freire et al, 2015; Stiefel et al, 2015; Park and Kim, 2018). However, none of the published studies have established an assay in which cultures are grown and stained in the same media, and no improvements on the green to red fluorescence ratio have been made.…”

Section: Introductionmentioning

confidence: 99%

Optimisation of the Protocol for the LIVE/DEAD® BacLightTM Bacterial Viability Kit for Rapid Determination of Bacterial Load

et al. 2019

View full text Add to dashboard Cite

Rapid antimicrobial susceptibility testing is needed to reduce prescription of inappropriate antibiotics. A rapid alternative to standard culture-based testing is to determine reductions in cell viability using the LIVE/DEAD ® BacLight TM Bacterial Viability Kit. We optimised the kit protocol for this application, focusing on simplifying the process by minimising the steps involved and on determining the optimal analytical parameters for fluorescence measurements from the dyes SYTO 9 and propidium iodide (PI). We demonstrate that for our experimental system, the intensity of emissions should be integrated from 505–515 nm for SYTO 9 and 600–610 nm for PI, and the proportion of live cells calculated from a new dye ratio formula, termed the adjusted dye ratio. We show that the pre-staining washing step is not necessary if a non-fluorescent growth media is used; however, staining must be done for each sampling as prolonged exposure to the dyes negatively impacts cell viability. The optimised methodology was able to reproducibly detect reductions in culture viability when the proportion of live cells in a sample of 1 × 10 8 cells/ml fell below ∼50% live in a media that supports the growth required for detecting antibiotic killing. Finally, we show that the interaction of fluorescence emission spectra from SYTO 9 and PI stained Escherichia coli cells is influenced by the proportion of dead cells in a sample. The excitation of PI by SYTO 9 was found to occur in populations containing sufficient numbers of dead cells (>25%), whereas in populations with low numbers of dead cells the dye interaction was additive in regard to red emissions, indicating that these dye interactions may offer another dimension to live/dead analysis. Fluorescence measurements from samples established according to the optimised protocol can be taken using a flow cytometer, spectrofluorometer, microplate reader, and the Optrode, a fibre-based spectroscopic system developed at the University of Auckland.

show abstract

Section: Introductionmentioning

confidence: 99%

Optimisation of the Protocol for the LIVE/DEAD® BacLightTM Bacterial Viability Kit for Rapid Determination of Bacterial Load

et al. 2019

View full text Add to dashboard Cite

show abstract

“…The Molecular Probes Bac Light stains are compatible across numerous bacterial species such as Agrobacterium tumefaciens , Clostridium perfringens , Klebsiella pneumoniae , Pseudomonas aeruginosa , Salmonella oranienburg , Staphylococcus aureus and Streptococcus pyogenes ( Hu et al, 2017 ; Lindbäck et al, 2010 ; Park and Kim, 2018 ; Robertson et al, 2019 ; Molecular Probes, 2004 ). The Biotium stains have been used with E. coli, Leptothrix , Lactobacillus fermentum, Lactobacillus reuteri , Pleurotus osreatus , and Salmonella enterica , ( Adamski and Pietr, 2019 ; Bhave et al, 2015 ; Duplantis et al, 2015 ; Furutani et al, 2011 ; Hernandez et al, 2012 ; Kim et al, 2016 ; Rodes et al, 2013 ; Biotium, 2020 ).…”

Section: Before You Beginmentioning

confidence: 99%

A simple, quantitative assay for the detection of viable but non-culturable (VBNC) bacteria

Arvizu

Murray

2021

STAR Protocols

View full text Add to dashboard Cite

Summary This protocol determines the fraction of a bacterial population that is viable and culturable, viable and non-culturable, or non-viable (dead). Each population is detected by isolating colonies on agar plates, performing direct counts, and staining for live or dead cells. Its application is limited to bacteria that are stainable and when permissible growth conditions are known. The quantitative data extracted allow for the detection of a viable but non-culturable (alive and non-dividing) population from a liquid culture. For complete details on the use and execution of this protocol, please refer to Stott et al. (2015) .

show abstract

“… Fluorescence microscopy images with live/ dead staining (a) control (b) disinfected by hypochlorite (c) isopropanol (d) peroxide in HCl, (e) thermal treatment …”

Section: Recent Advancement In the Area Of Disinfection Researchmentioning

confidence: 99%

Bacterial Lysis via Photocatalysis ‐ A Critical Mechanistic Review

Gupta

Modak

2020

ChemCatChem

View full text Add to dashboard Cite

This Review discusses one of the most important area of photocatalytic reactions. In current research scenario, photocatalysis is well utilized strategy for a wide variety of applications including organic/ inorganic decontamination, solar fuel generation, microbial disinfection etc. This Review touches upon the mechanistic aspect of microbial disinfection, the growth in the research, issues to be addressed in future to make it a sustainable technology for this application. This Review discusses the fundamental understanding of photocatalysis, important strategies to tune their optical properties to enhance the spectral range of absorption in visible and near infrared wavelength region. Various photocatalysis reports these days don't focus on the stability, reusability and recovery of the photocatalysts. However, these issues are very important to deal with for large scale viability of the process. Therefore, we have tried to address these issues along with the detailed experimental information and eliminate the misconceptions about bacterial disinfection. The details provided in this Review would help the researchers working in this area to a large extent and would open various questions for them to answer.

show abstract

A comparative study of three different viability tests for chemically or thermally inactivated Escherichia coli

Cited by 17 publications

References 18 publications

Optimisation of the Protocol for the LIVE/DEAD® BacLightTM Bacterial Viability Kit for Rapid Determination of Bacterial Load

Optimisation of the Protocol for the LIVE/DEAD® BacLightTM Bacterial Viability Kit for Rapid Determination of Bacterial Load

A simple, quantitative assay for the detection of viable but non-culturable (VBNC) bacteria

Bacterial Lysis via Photocatalysis ‐ A Critical Mechanistic Review

Contact Info

Product

Resources

About