Investigation of Oxygen Consumption by E. coli Immobilized in a Synthetic Biofilm Using a Thin Film Plug Reactor (TFPR)

AbstractCardiolipin (CL) is a lipid that is found in the membranes of bacteria and the inner membranes of mitochondria. CL can increase the activity of integral membrane proteins, in particular components of respiratory pathways. We here report that CL activated detergent-solubilized cytochrome bd, a terminal oxidase from Escherichia coli. CL enhanced the oxygen consumption activity ~ twofold and decreased the apparent KM value for ubiquinol-1 as substrate from 95 µM to 35 µM. Activation by CL was also observed for cytochrome bd from two Gram-positive species, Geobacillus thermodenitrificans and Corynebacterium glutamicum, and for cytochrome bo3 from E. coli. Taken together, CL can enhance the activity of detergent-solubilized cytochrome bd and cytochrome bo3.

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Visible Light Photocatalytic Activity of Thin Film Coated on Polycarbonate Surface with N- and Ni-Codoped TiO2 Photocatalyst

Catalysts ◽

10.3390/catal10111237 ◽

2020 ◽

Vol 10 (11) ◽

pp. 1237

Author(s):

Byung-Geon Park ◽

Chang-Ho Lee ◽

Kyong-Hwan Chung

Keyword(s):

Thin Film ◽

Visible Light ◽

Pathogenic Bacteria ◽

Sol Gel ◽

Photocatalytic Reaction ◽

Tio2 Photocatalyst ◽

E Coli ◽

Amorphous Tio2 ◽

Visible Light Photocatalytic ◽

Decomposition Properties

N- and Ni-coated TiO2 (NNT) were prepared by a facile sol-gel method as a photosensitive photocatalyst to visible light. NNT sol was used to coat the surface of an LED lamp cap and body made of polycarbonate with a thin NNT film. The coated thin film was dried in an oven at 130 °C. This NNT thin film had an amorphous TiO2 structure and absorbed 600 nm of visible light. The decomposition properties of formaldehyde on the NNT photocatalyst after irradiation with visible light were investigated. The LED lamp was irradiated with visible light at 500–620 nm and 6 W. Formaldehyde was decomposed by a photocatalytic reaction by visible light irradiation on the NNT-coated polycarbonate surface. Escherichia coli (E. coli), Staphylococcus aureus, and Pseudomonas aeruginosa were also used to examine the sterilizing properties of pathogenic bacteria using an LED lamp kit. The pathogenic bacteria on the NNT-coated polycarbonate surface were sterilized by irradiation with visible light.

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STUDIES ON VARIOUS FUNCTIONAL PROPERTIES OF TITANIA THIN FILM DEVELOPED ON GLAZED CERAMIC WALL TILES

International Journal of Modern Physics Conference Series ◽

10.1142/s2010194513009951 ◽

2013 ◽

Vol 22 ◽

pp. 79-92 ◽

Cited By ~ 3

Author(s):

ASHA ANIL ◽

BANGORIA DARSHANA R ◽

S. N. MISRA

Keyword(s):

Thin Film ◽

Functional Properties ◽

Curing Temperature ◽

Alkali Resistance ◽

Bacterial Reduction ◽

E Coli ◽

Coated Substrate ◽

Stain Resistance ◽

Increase With Increase ◽

Coated Surface

A sol-gel based TiO 2 thin film was applied on glazed wall tiles for studying its various functional properties. Thin film was deposited by spin coating on the substrate and subjected to curing at different temperatures such as 600°C, 650, 700°C, 750°C and 800°C with 10 minutes soaking. The gel powder was characterized by FTIR, DTA/TG and XRD. Microstructure of thin film was analyzed by FESEM and EDX. Surface properties of the coatings such as gloss, colour difference, stain resistance, mineral hardness and wettability were extensively studied. The antibacterial activity of the surface of coated substrate against E. coli was also examined. The durability of the coated substrate in comparison to the uncoated was tested against alkali in accordance with ISO: 10545 (Part 13):1995 standard. FESEM images showed that thin films are dense and homogeneous. Coated substrates after firing results in lustre with high gloss, which increased from 330 to 420 GU as the curing temperature increases compared to that of uncoated one (72 GU). Coated substrate cured at 800°C shows higher mineral hardness (5 Mohs’) compared to uncoated one (4 Mohs’) and films cured at all temperatures showed stain resistance. The experimental results showed that the resistance towards alkali attack increase with increase in curing temperature and alkali resistance of sample cured at 800 °C was found to be superior compared to uncoated substrate. Contact angle of water on coated surface of substrates decreased with increase in temperature. Bacterial reduction percentages of the coated surface was 97% for sample cured at 700°C and it decreased from 97% to 87% as the curing temperature increased to 800 °C when treated with E. coli bacteria.

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THE EFFECTS OF SULFATHIAZOLE AND OF PROPYL CARBAMATE ON THE RATE OF OXYGEN CONSUMPTION AND GROWTH IN ESCHERICHIA COLI

The Journal of General Physiology ◽

10.1085/jgp.30.3.263 ◽

1947 ◽

Vol 30 (3) ◽

pp. 263-278 ◽

Cited By ~ 6

Author(s):

Kenneth C. Fisher ◽

Florence H. Armstrong

Keyword(s):

Escherichia Coli ◽

Oxygen Consumption ◽

Cell Count ◽

Optical Density ◽

Viable Cell ◽

E Coli ◽

Rate Of Growth ◽

A Value ◽

Rate Of Oxygen Consumption ◽

Rates Of Growth

1. The rates of growth and of oxygen consumption by cells of E. coli have been measured under identical conditions, and the effects of sulfathiazole (ST) and of n-propyl carbamate (PC) on these two processes have been compared. 2. The rate of growth was measured by (a) the increase in the viable cell count, (b) the increase in the optical density of the culture, (c) the increase in the rate of oxygen consumption, and (d) the decrease in the ammonia of the medium. The results as indicated by these several measures were identical under the conditions of these experiments. 3. Concentrations of ST or of PC which are just sufficient to stop growth completely, lower the rate of oxygen consumption per unit of bacterial protoplasm to a value approximately 50 per cent of that seen in the absence of the inhibitor. 4. It is shown that the rate of oxygen consumption in cells from old cultures is less affected by ST than is the rate of oxygen consumption by cells from young cultures. It is probable that the rate of oxygen consumption by "old" cells is lower than that of "young" cells. 5. The effects of ST and PC on both the rate of oxygen consumption and the rate of growth are very similar, indicating in a general way, that the mechanism of the actions of these two inhibitors is similar. Furthermore, since both of them produce appreciable inhibition of the rate of oxygen consumption while they are inhibiting growth, the possibility that the effect on oxygen consumption is the immediate cause of the effect on growth must be entertained.

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Efficacy of Ultraviolet Light for Reducing Escherichia coli O157:H7 in Unpasteurized Apple Cider

Journal of Food Protection ◽

10.4315/0362-028x-63.5.563 ◽

2000 ◽

Vol 63 (5) ◽

pp. 563-567 ◽

Cited By ~ 133

Author(s):

J. R. WRIGHT ◽

S. S. SUMNER ◽

C. R. HACKNEY ◽

M. D. PIERSON ◽

B. W. ZOECKLEIN

Keyword(s):

Thin Film ◽

Escherichia Coli ◽

Uv Light ◽

Uv Disinfection ◽

Escherichia Coli O157 ◽

Apple Cider ◽

E Coli ◽

Log Reduction ◽

Disinfection Unit ◽

Additional Reduction

This study examined the efficacy of UV light for reducing Escherichia coli O157:H7 in unpasteurized cider. Cider containing a mixture of acid-resistant E. coli O157:H7 (6.3 log CFU/ml) was treated using a thin-film UV disinfection unit at 254 nm. Dosages ranged from 9,402 to 61,005 μW-s/cm2. Treatment significantly reduced E. coli O157:H7 (P ≤ 0.0001). Mean reduction for all treated samples was 3.81 log CFU/ml. Reduction was also affected by the level of background microflora in cider. Results indicate that UV light is effective for reducing this pathogen in cider. However, with the dosages used in this experiment, additional reduction measures are necessary to achieve the required 5-log reduction.

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DYNAMIC BEHAVIOR OF METHYLENE BLUE ON E. coli K30 CAPSULAR POLYSACCHARIDE USING LAYER BY LAYER SELF-ASSEMBLY TECHNIQUE

Surface Review and Letters ◽

10.1142/s0218625x20500274 ◽

2020 ◽

pp. 2050027

Author(s):

BANDANA DAS ◽

ALPANA BAIDYA ◽

SANTANU MAJUMDER ◽

RANENDU KUMAR NATH

Keyword(s):

Thin Film ◽

Methylene Blue ◽

Dynamic Behavior ◽

Self Assembly ◽

Capsular Polysaccharide ◽

Layer By Layer ◽

Cationic Dye ◽

Bacterial Polysaccharide ◽

E Coli ◽

Assembly Technique

Layer-by-layer (LbL) self-assembly is one of the unique methods for fabrication of ultra-thin film. This technique has immense application aross many fields in today’s life. In this paper, we have presented the fabrication of the thin film comprising of antifungal and antibacterial cationic dye methylene blue with negatively charged E. coli K30 bacterial polysaccharide sharing with PAH. The multilayers were characterized by UV–Vis absorption spectra and AFM. Various photophysical behaviors were investigated. Such studies provide a new light in the research of layer by layer self-assembly technique.

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Synthesis of Mesoporous SBA-16 and SBA-16/ZnO2 Nano-Composite Thin Film for Anti-Biofilm Application

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2020.17539 ◽

2020 ◽

Vol 20 (7) ◽

pp. 4210-4215 ◽

Cited By ~ 3

Author(s):

Atul Kumar ◽

Suman Gahlyan ◽

Rajesh Thakur ◽

Sunita Devi ◽

Surender Duhan

Keyword(s):

Thin Film ◽

Thin Films ◽

High Surface ◽

High Surface Area ◽

Zno Nanoparticle ◽

Bacterial Cells ◽

Nano Composite ◽

Cubic Symmetry ◽

X Ray ◽

E Coli

SBA-16 is a mesoporous nanostructure with high surface area and cubic symmetry which make them an ideal carrier to carry different nanoparticles. Zinc peroxide (ZnO2) is a novel nanoparticle that inhibits the growth of microorganisms due to its antiseptic property. Thin film of SBA-16 and SBA-16/ZnO2 was deposited on glass slide by spin coating method. Anti-biofilm property of the thin films was examined against E. coli and S. aureus bacteria. Structural property was found out by wide angle X-ray diffraction (XRD), small angle X-ray scattering (SAXS) and High Resolution Transmission Electron Microscope (HRTEM). Fourier Transform Infrared Spectrophotometer (FTIR) was used to confirmation the presence of ZnO2 in Nano-composite and AFM utilized for surface topography of thin films. Fluorescent microscope image clearly revealed that SBA-16/ZnO2 nanocomposite thin film significantly inhibit the biofilm formation against both E. coli (gram negative bacteria) as well as S. aureus (gram positive bacteria) in comparision to SBA-16. The antimicrobial behavior of ZnO nanoparticle is due to formation of H2O2 as reactive oxygen species (ROS) to which the bacterial cells are permeable. H2O2 is a powerful oxidizing agents that oxidized the mycobacterial elements like DNA and proteins which results into the toxicity of the bacteria cell.

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Synthesis and Characterization of PVA-Ag Doped Metals (Co, Al) Nanocomposite Thin Films Biosensors for Detection of E. coli in Water

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1107.706 ◽

2015 ◽

Vol 1107 ◽

pp. 706-711 ◽

Cited By ~ 1

Author(s):

Norshafadzila Mohammad Naim ◽

Huda Abdullah ◽

Noor Azwen Noor Azmy ◽

Aidil Abdul Hamid ◽

Mohd Ambar Yarmo ◽

...

Keyword(s):

Thin Film ◽

Thin Films ◽

Chemical Reduction ◽

Sol Gel ◽

Xrd Analysis ◽

Spherical Particles ◽

Nanocomposite Thin Film ◽

Plasmon Band ◽

E Coli ◽

Al Nanoparticles

Polyvinyl alcohol (PVA) doped with Ag thin films were synthesized from aqueous solution via sol gel method. The nanoparticle of silver was synthesized by chemical reduction using hydrazine hydrate. PVA-Ag thin films were deposited on the glass substrate by spin coating technique. Samples were varied with different combinations of metals such as Ag-Co and Ag-Al. The solutions and the films were characterized by using XRD, UV-Visible spectroscopy, AFM and TEM. XRD analysis indicates the formation of the single crystal Ag, Co and Al nanoparticles laid on (111) lattice planes. The crystallite sizes decrease when Co and Al are added to the PVA-Ag. UV-Vis absorption spectra confirmed the formation of Ag nanoparticles in the PVA matrix and the resonance plasmon band located at 417, 421 and 429 nm. Surface roughness of PVA-Ag nanocomposite thin film increased with the addition of Co and Al. TEM images show the non-agglomerated spherical particles in all samples. The performance of the sensor has been fabricated usingI-Vmeasurement with and without incubated the sensor electrode intoE. coli. The result shows PVA-Ag nanocomposite thin film performed the higher sensitivity.

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Synthesis Photocatalytic TiO2/ZnO Nanocomposite and Investigation through Anatase, Wurtzite and ZnTiO3 Phases Antibacterial Behaviors

Journal of Nano Research ◽

10.4028/www.scientific.net/jnanor.51.69 ◽

2018 ◽

Vol 51 ◽

pp. 69-77 ◽

Cited By ~ 3

Author(s):

Hanif Mohammadi ◽

Mohammad Ghorbani

Keyword(s):

Thin Film ◽

Thin Films ◽

Antibacterial Activity ◽

Uv Light ◽

Sol Gel ◽

Molar Ratio ◽

Plate Count ◽

Gel Method ◽

Sol Gel Method ◽

E Coli

Titanium dioxide is prepared by sol gel method from titanium tetraisopropoxide (TTIP) as precursor and likewise zinc oxide is prepared by sol gel method from zinc acetate dehydrate (ZAD) as precursor. The composite sols are prepared in three different molar ratios 90TiO2:10ZnO, 70TiO2:30ZnO and 50TiO2:50ZnO. Thin film deposition is carried out by dip coating technique. Crystal structure, surface morphology and photocatalytic activity of the prepared nanocomposite thin films are investigated. The antibacterial activity of the prepared nanocomposite thin film against E-coli ATCC 25922 bacteria is examined by placing the thin film in standard aqueous E-coli medium under UV light for 1, 2, 3 and 4 hours and then counting the bacteria with Standard Plate Count Agar (SPC) technique. The prepared thin films have shown strong antibacterial activity in the presence of UV light and by increasing the ZnO molar ratio from 10 to 50, antibacterial activity of the thin films decreases because of decreases in the anatase phase of the TiO2. In the dark conditions by increasing the molar ratio of ZnO, the antibacterial activity of the thin films increases and this phenomenon is related to increasing the zinc ions in the thin films.

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