scholarly journals Efficacy and Mechanism of Ultrasound Combined with Slightly Acidic Electrolyzed Water for Inactivating Escherichia coli

2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Liping Guo ◽  
Xuecong Zhang ◽  
Lin Xu ◽  
Yan Li ◽  
Bin Pang ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Particle Size ◽  
Protein Conformation ◽  
Synergetic Effect ◽  
Transmission Electron Microscopy Analysis ◽  
Electrolyzed Water ◽  
E Coli ◽  
Transmission Electron ◽  
Electron Microscopy Analysis ◽  
Sterilization Mechanism

In the present study, the synergetic effect and mechanism of ultrasound (US) and slightly acidic electrolyzed water (SAEW) on the inactivation of Escherichia coli (E. coli) were evaluated. The results showed that US combined with SAEW treatment showed higher sanitizing efficacy for reducing E. coli than US and SAEW alone treatment. US and US combined with SAEW treatments resulted in smaller particle size of E. coli compared to the control and SAEW treatment. In addition, US combined with SAEW treatment induced the highest potassium leakage. However, the highest protein leakage was recorded in US treatment. Moreover, scanning and transmission electron microscopy analysis revealed that the greatest damage of the appearance and ultrastructure of E. coli was achieved after US combined with SAEW treatment. The synergetic effect was also confirmed by CLSM analysis. Fluorescence spectroscopy suggested that treatments of US, SAEW, and US combined with SAEW changed protein conformation of E. coli. Overall, the present study demonstrated that the sterilization mechanism of US combined with SAEW treatment was decreasing the particle size and disrupting the permeability of cell membrane and the cytoplasmic ultrastructure as well as changing protein conformation of E. coli.

Effect of Slightly Acidic Electrolyzed Water for Inactivating Escherichia coli O157:H7 and Staphylococcus aureus Analyzed by Transmission Electron Microscopy

2010 ◽  
Vol 73 (12) ◽  
pp. 2211-2216 ◽  
Author(s):  
SONGJIAN NAN ◽  
YONGYU LI ◽  
BAOMING LI ◽  
CHAOYUAN WANG ◽  
XIAODONG CUI ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Transmission Electron Microscopy ◽  
Treatment Time ◽  
Escherichia Coli O157 ◽  
Electrolyzed Water ◽  
E Coli ◽  
Transmission Electron ◽  
And Staphylococcus Aureus

The use of different available chlorine concentrations (ACCs) of slightly acidic electrolyzed water (SAEW; 0.5 to 30 mg/liter), different treatment times, and different temperatures for inactivating Escherichia coli O157:H7 and Staphylococcus aureus was evaluated. The morphology of both pathogens also was analyzed with transmission electron microscopy. A 3-min treatment with SAEW (pH 6.0 to 6.5) at ACCs of 2 mg/liter for E. coli O157:H7 and 8 mg/liter for S. aureus resulted in 100% inactivation of two cultures (7.92- to 8.75-log reduction) at 25°C. The bactericidal activity of SAEW was independent of the treatment time and temperature at a higher ACC (P > 0.05). E. coli O157:H7 was much more sensitive than S. aureus to SAEW. The morphological damage to E. coli O157:H7 cells by SAEW was significantly greater than that to S. aureus cells. At an ACC as high as 30 mg/liter, E. coli O157:H7 cells were damaged, but S. aureus cells retained their structure and no cell wall damage or shrinkage was observed. SAEW with a near neutral pH may be a promising disinfectant for inactivation of foodborne pathogens.

CHARACTERIZATION AND ELECTRICAL PROPERTIES OF ALIGNED CARBON NANOTUBES WITH HIGH ASPECT RATIO

2011 ◽  
Vol 10 (01n02) ◽  
pp. 23-28
Author(s):  
RAVI BHATIA ◽  
V. PRASAD ◽  
M. REGHU
Keyword(s):  
Electron Microscopy ◽  
Carbon Nanotubes ◽  
Aspect Ratio ◽  
Multiwall Carbon Nanotubes ◽  
High Quality ◽  
Transmission Electron Microscopy Analysis ◽  
Transmission Electron ◽  
Electron Microscopy Analysis ◽  
High Degree

High-quality multiwall carbon nanotubes (MWNTs) were produced by a simple one-step technique. The production of MWNTs was based on thermal decomposition of the mixture of a liquid phase organic compound and ferrocene. High degree of alignment was noticed by scanning electron microscopy. The aspect ratio of as-synthesized MWNTs was quite high (more than 4500). Transmission electron microscopy analysis showed the presence of the catalytic iron nanorods at various lengths of MWNTs. Raman spectroscopy was used to know the quality of MWNTs. The ratio of intensity of the G-peak to the D-peak was very high which revealed high quality of MWNTs. Magnetotransport studies were carried out at low temperature and a negative MR was noticed.

scholarly journals Thermodynamic Modelling and Microstructural Study of Z-Phase Formation in a Ta-Alloyed Martensitic Steel

Materials ◽  
2021 ◽  
Vol 14 (6) ◽  
pp. 1332
Author(s):  
Florian Riedlsperger ◽  
Bernadette Gsellmann ◽  
Erwin Povoden-Karadeniz ◽  
Oriana Tassa ◽  
Susanna Matera ◽  
...  
Keyword(s):  
Special Focus ◽  
Scanning Calorimetry ◽  
Transmission Electron Microscopy Analysis ◽  
Computational Framework ◽  
Mobility Data ◽  
Interfacial Energies ◽  
Transmission Electron ◽  
Size Number ◽  
Electron Microscopy Analysis ◽  
Microscopy Analysis

A thermokinetic computational framework for precipitate transformation simulations in Ta-containing martensitic Z-steels was developed, including Calphad thermodynamics, diffusion mobility data from the literature, and a kinetic parameter setup that considered precipitation sites, interfacial energies and dislocation density evolution. The thermodynamics of Ta-containing subsystems were assessed by atomic solubility data and enthalpies from the literature as well as from the experimental dissolution temperature of Ta-based Z-phase CrTaN obtained from differential scanning calorimetry. Accompanied by a comprehensive transmission electron microscopy analysis of the microstructure, thermokinetic precipitation simulations with a wide-ranging and well-documented set of input parameters were carried out in MatCalc for one sample alloy. A special focus was placed on modelling the transformation of MX into the Z-phase, which was driven by Cr diffusion. The simulation results showed excellent agreement with experimental data in regard to size, number density and chemical composition of the precipitates, showing the usability of the developed thermokinetic simulation framework.

scholarly journals Morphological changes and bioaccumulation in response to cadmium exposure in Morchella spongiola, a fungus with potential for detoxification

2021 ◽  
Author(s):  
Hongyan Xu ◽  
Jing Guo ◽  
Qing Meng ◽  
Zhanling Xie
Keyword(s):  
Electron Microscopy ◽  
Morphological Changes ◽  
Intracellular Accumulation ◽  
Tolerance Mechanism ◽  
Edible Fungi ◽  
Transmission Electron Microscopy Analysis ◽  
Transmission Electron ◽  
Electron Microscopy Analysis ◽  
Microscopy Analysis ◽  
Micro Morphology

<i>Morchella</i> is a genus of edible fungi with strong resistance to Cd and the ability to accumulate it in the mycelium. However, the mechanisms conferring Cd resistance in <i>Morchella</i> are unknown. In the present study, morphological and physiological responses to Cd were evaluated in the mycelia of <i>Morchella spongiola</i>. Variations in hyphal micro-morphology including twisting, folding and kinking in mycelia exposed to different Cd concentrations (0.15, 0.9, 1.5, 2.4, 5.0 mg/L) were observed using scanning electron microscopy. Deposition of Cd precipitates on cell surfaces (at Cd concentrations > 2.4 mg/L) was shown by SEM-EDS. Transmission electron microscopy analysis of cells exposed to different concentrations of Cd revealed the loss of intracellular structures and the localization of Cd depositions inside/outside the cell. FTIR analysis showed that functional groups such as C=O, -OH, -NH and -CH could be responsible for Cd binding on the cell surface of <i>M. spongiola</i>. In addition, intracellular accumulation was observed in cultures at low Cd concentrations (< 0.9 mg/L), while extracellular adsorption occurred at higher concentrations. These results provide valuable information on the Cd tolerance mechanism in <i>M. spongiola</i> and constitute a robust foundation for further studies on fungal bioremediation strategies.

Sign in / Sign up

Export Citation Format

Share Document