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Rezaeimotlagh A, Resch M, Kuchel RP, Biazik J, Ziuzina D, Bourke P, Cullen P, Trujillo FJ. Unveiling the synergistic effect of combining low and high frequency electric fields for microbiological safety in liquid food processing. J FOOD ENG 2021. [DOI: 10.1016/j.jfoodeng.2021.110588] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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2
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Kasri NF, Piah MAM, Hamzah A, Adzis Z. Microcontroller‐based pulse signal controller development for compact high voltage pulse generator: Practical development in food treatment technology. J FOOD PROCESS PRES 2021. [DOI: 10.1111/jfpp.15531] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- N. F. Kasri
- School of Electrical Engineering Universiti Teknologi Malaysia Skudai Malaysia
| | - M. A. M. Piah
- School of Electrical Engineering Universiti Teknologi Malaysia Skudai Malaysia
| | - A. Hamzah
- School of Electrical Engineering Universiti Teknologi Malaysia Skudai Malaysia
| | - Z. Adzis
- School of Electrical Engineering Universiti Teknologi Malaysia Skudai Malaysia
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3
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Poudel A, Oludiran A, Sözer EB, Casciola M, Purcell EB, Muratori C. Growth in a biofilm sensitizes Cutibacterium acnes to nanosecond pulsed electric fields. Bioelectrochemistry 2021; 140:107797. [PMID: 33773215 DOI: 10.1016/j.bioelechem.2021.107797] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Revised: 02/24/2021] [Accepted: 02/26/2021] [Indexed: 10/21/2022]
Abstract
The Gram-positive anaerobic bacterium Cutibacterium acnes (C. acnes) is a commensal of the human skin, but also an opportunistic pathogen that contributes to the pathophysiology of the skin disease acne vulgaris. C. acnes can form biofilms; cells in biofilms are more resilient to antimicrobial stresses. Acne therapeutic options such as topical or systemic antimicrobial treatments often show incomplete responses. In this study we measured the efficacy of nanosecond pulsed electric fields (nsPEF), a new promising cell and tissue ablation technology, to inactivate C. acnes. Our results show that all tested nsPEF doses (250 to 2000 pulses, 280 ns pulses, 28 kV/cm, 5 Hz; 0.5 to 4 kJ/ml) failed to inactivate planktonic C. acnes and that pretreatment with lysozyme, a naturally occurring cell-wall-weakening enzyme, increased C. acnes vulnerability to nsPEF. Surprisingly, growth in a biofilm appears to sensitize C. acnes to nsPEF-induced stress, as C. acnes biofilm-derived cells showed increased cell death after nsPEF treatments that did not affect planktonic cells. Biofilm inactivation by nsPEF was confirmed by treating intact biofilms grown on glass coverslips with an indium oxide conductive layer. Altogether our results show that, contrary to other antimicrobial agents, nsPEF kill more efficiently bacteria in biofilms than planktonic cells.
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Affiliation(s)
- Asia Poudel
- Old Dominion University, Department of Chemistry and Biochemistry, USA
| | - Adenrele Oludiran
- Old Dominion University, Department of Chemistry and Biochemistry, USA
| | - Esin B Sözer
- Old Dominion University, Frank Reidy Research Center for Bioelectrics, USA
| | - Maura Casciola
- Old Dominion University, Frank Reidy Research Center for Bioelectrics, USA; Center for Devices and Radiological Health, US Food and Drug Administration, Silver Spring, MD 20993, USA
| | - Erin B Purcell
- Old Dominion University, Department of Chemistry and Biochemistry, USA.
| | - Claudia Muratori
- Old Dominion University, Frank Reidy Research Center for Bioelectrics, USA.
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4
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Electrical systems for pulsed electric field applications in the food industry: An engineering perspective. Trends Food Sci Technol 2020. [DOI: 10.1016/j.tifs.2020.07.008] [Citation(s) in RCA: 66] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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5
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Compact High-Voltage Pulse Generator for Pulsed Electric Field Applications: Lab-Scale Development. JOURNAL OF ELECTRICAL AND COMPUTER ENGINEERING 2020. [DOI: 10.1155/2020/6525483] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Square wave pulses have been identified as more lethal compared to exponential decay pulses in PEF applications. This is because of the on-time which is longer causes a formidable impact on the microorganisms in the food media. To have a reliable high-voltage pulse generator, a technique of capacitor discharge was employed. Four units of capacitor rated 100 μF 1.2 kV were connected in series to produce 25 μF 4.8 kV which were used to store the energy of approximately 200 J. The energy stored was discharged via HTS 181-01-C to the load in the range of nano to microseconds of pulse duration. The maximum voltage applied was limited to 4 kV because it is a lab-scale project. The electrical circuit diagram and the development procedure, as well as experimental results, are presented.
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6
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Ballash GA, Lee S, Mollenkopf DF, Mathys DA, Albers AL, Sechrist E, Feicht SM, Van Balen Rubio JC, Sullivan SMP, Lee J, Wittum TE. Pulsed electric field application reduces carbapenem- and colistin-resistant microbiota and bla KPC spread in urban wastewater. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2020; 265:110529. [PMID: 32421557 DOI: 10.1016/j.jenvman.2020.110529] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 03/24/2020] [Accepted: 03/28/2020] [Indexed: 06/11/2023]
Abstract
Wastewater flows from metropolitan areas, especially those with healthcare inputs, can serve as transport reservoirs for the dissemination of clinically-relevant antimicrobial resistant bacteria (ARB) such as carbapenem- (CR) and colistin-resistant (CoR) strains. Pulsed electric field (PEF) is an emerging wastewater management tool for reducing bacterial loads without generating environmentally harmful byproducts, but it's ability to reduce ARB and their genetic determinants is not well reported. We collected 86, 10-L raw wastewater influent samples from a large metropolitan wastewater treatment plant in Columbus, Ohio and subjected them to low (34 kV cm-1 for 67 μsec) and high (36 kV cm-1 for 89 μsec) PEF treatment. We quantified the PEF effectiveness by measuring concentrations of total coliform bacteria, CR and CoR bacteria, and the epidemic carbapenemase gene, blaKPC, before and after PEF treatment. Utilizing marginal linear regression models with generalized estimating equations, we observed that low and high PEF treatment resulted in a 1.94 (95% CI 2.06-1.81; P < 0.001) and 2.32 (95% CI 2.46-2.18; P < 0.001) log reduction of total coliform bacteria concentrations, respectively. Low and high PEF treatment produced similar log reductions between CR E. coli (2.01 (95% CI 2.15-1.86; P < 0.001); 2.14 (95% CI: 5.30-4.61; P < 0.001)) and CR Enterobacteriaceae concentrations (1.55 (95% CI 1.70-1.41; P < 0.001); 1.86 (95% CI 2.05-1.68; P < 0.001)), and resulted in a 1.15 log (95% CI 1.38-0.93, P < 0.001) and 1.28 log (95% CI 1.54-1.03, P < 0.001) reduction of absolute blaKPC concentrations. Log CoR E. coli concentrations were reduced by 2.47 (95% CI 2.78-2.15; P < 0.001) and 2.52 (95% CI 2.91-2.15; P < 0.001) and CoR Enterobacteriaceae by 2.24 (95% CI 2.52-1.95; P < 0.001) and 2.50 (95% CI 2.89-2.11; P < 0.001) following low and high PEF application. PEF can be applied for wastewater management as an independent treatment method, particularly at critical control points, such as an on-site management of wastewater from hospitals or other healthcare facilities, or in series with other conventional methods to reduce total bacterial loads and concentrations of clinically-relevant ARB.
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Affiliation(s)
- Gregory A Ballash
- Department of Veterinary Preventive Medicine, College of Veterinary Medicine, The Ohio State University, Columbus, OH, 43210, USA
| | - Seungjun Lee
- Division of Environmental Health Sciences, College of Public Health, The Ohio State University, Columbus, OH, 43210, USA
| | - Dixie F Mollenkopf
- Department of Veterinary Preventive Medicine, College of Veterinary Medicine, The Ohio State University, Columbus, OH, 43210, USA
| | - Dimitria A Mathys
- Department of Veterinary Preventive Medicine, College of Veterinary Medicine, The Ohio State University, Columbus, OH, 43210, USA
| | - Amy L Albers
- Department of Veterinary Preventive Medicine, College of Veterinary Medicine, The Ohio State University, Columbus, OH, 43210, USA
| | - Emily Sechrist
- Department of Veterinary Preventive Medicine, College of Veterinary Medicine, The Ohio State University, Columbus, OH, 43210, USA
| | - Sydnee M Feicht
- Department of Veterinary Preventive Medicine, College of Veterinary Medicine, The Ohio State University, Columbus, OH, 43210, USA
| | - Joanny C Van Balen Rubio
- Department of Veterinary Preventive Medicine, College of Veterinary Medicine, The Ohio State University, Columbus, OH, 43210, USA
| | - S Mažeika P Sullivan
- Schiermeier Olentangy River Wetland Research Park, School of Environment and Natural Resources, College of Food Agricultural and Environmental Sciences, The Ohio State University, Columbus, OH, 43202, USA
| | - Jiyoung Lee
- Division of Environmental Health Sciences, College of Public Health, The Ohio State University, Columbus, OH, 43210, USA; Department of Food Science & Technology, College of Food Agricultural and Environmental Sciences, The Ohio State University, Columbus, OH, 43210, USA
| | - Thomas E Wittum
- Department of Veterinary Preventive Medicine, College of Veterinary Medicine, The Ohio State University, Columbus, OH, 43210, USA.
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7
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Nanosecond pulses targeting intracellular ablation increase destruction of tumor cells with irregular morphology. Bioelectrochemistry 2019; 132:107432. [PMID: 31918056 DOI: 10.1016/j.bioelechem.2019.107432] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Revised: 11/22/2019] [Accepted: 11/22/2019] [Indexed: 01/04/2023]
Abstract
The decrease in killing sensitivity of the cell membrane to microsecond pulse electric fields (μs-PEFs) is ascribed mainly to the aberrant morphology of cancer cells, with clear statistical correlations observed between cell size and shape defects and the worsening of the electrical response to the PEF. In this paper, nanosecond pulsed electric fields (ns-PEFs) inducing the nucleus effect and μs-PEFs targeting the cell membrane were combined to enhance destruction of irregular cells. The fluorescence dissipation levels of the nuclear membrane and cell membrane exposed to the μs, ns, and ns + μs pulse protocols were measured and compared, and a dynamic electroporation model of irregular cells was established by the finite element software COMSOL. The results suggest that the cell membrane disruption induced by μs-PEFs is worse for extremely irregular cells and depends strongly on cellular morphology. However, the nuclear membrane disruption induced by ns-PEFs does not scale with irregularity, suggesting the use of a combination of ns-PEFs with μs-PEFs to target the nuclear and cell membranes. We demonstrate that ns + μs pulses can significantly enhance the fluorescence dissipation of the cell and nuclear membranes. Overall, our findings indicate that ns + μs pulses may be useful in the effective killing of irregular cells.
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8
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Microfluidic Irreversible Electroporation-A Versatile Tool to Extract Intracellular Contents of Bacteria and Yeast. Metabolites 2019; 9:metabo9100211. [PMID: 31574935 PMCID: PMC6835232 DOI: 10.3390/metabo9100211] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Revised: 09/25/2019] [Accepted: 09/27/2019] [Indexed: 02/06/2023] Open
Abstract
Exploring the dynamic behavior of cellular metabolism requires a standard laboratory method that guarantees rapid sampling and extraction of the cellular content. We propose a versatile sampling technique applicable to cells with different cell wall and cell membrane properties. The technique is based on irreversible electroporation with simultaneous quenching and extraction by using a microfluidic device. By application of electric pulses in the millisecond range, permanent lethal pores are formed in the cell membrane of Escherichia coli and Saccharomyces cerevisiae, facilitating the release of the cellular contents; here demonstrated by the measurement of glucose-6-phosphate and the activity of the enzyme glucose-6-phosphate dehydrogenase. The successful application of this device was demonstrated by pulsed electric field treatment in a flow-through configuration of the microfluidic chip in combination with sampling, inactivation, and extraction of the intracellular content in a few seconds. Minimum electric field strengths of 10 kV/cm for E. coli and 7.5 kV/cm for yeast S. cerevisiae were required for successful cell lysis. The results are discussed in the context of applications in industrial biotechnology, where metabolomics analyses are important.
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9
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Novickij V, Zinkevičienė A, Stanevičienė R, Gruškienė R, Servienė E, Vepštaitė-Monstavičė I, Krivorotova T, Lastauskienė E, Sereikaitė J, Girkontaitė I, Novickij J. Inactivation of Escherichia coli Using Nanosecond Electric Fields and Nisin Nanoparticles: A Kinetics Study. Front Microbiol 2018; 9:3006. [PMID: 30619116 PMCID: PMC6299027 DOI: 10.3389/fmicb.2018.03006] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Accepted: 11/20/2018] [Indexed: 01/24/2023] Open
Abstract
Nisin is a recognized bacteriocin widely used in food processing, however, being ineffective against gram-negative bacteria and in complex food systems. As a result, the research of methods that have cell wall–permeabilizing activity is required. In this study, electroporation to trigger sensitization of gram-negative bacteria to nisin-loaded pectin nanoparticles was used. As a model microorganism, bioluminescent strain of E. coli was introduced. Inactivation kinetics using nanosecond pulsed electric fields (PEFs) and nisin nanoparticles have been studied in a broad range (100–900 ns, 10–30 kV/cm) of pulse parameters. As a reference, the microsecond range protocols (100 μs × 8) have been applied. It was determined that the 20–30 kV/cm electric field with pulse duration ranging from 500 to 900 ns was sufficient to cause significant permeabilization of E. coli to trigger a synergistic response with the nisin treatment. The kinetics of the inactivation was studied with a time resolution of 2.5 min, which provided experimental evidence that the efficacy of nisin-based treatment can be effectively controlled in time using PEF. The results and the proposed methodology for rapid detection of bacteria inactivation rate based on bioluminescence may be useful in the development and optimization of protocols for PEF-based treatments.
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Affiliation(s)
- Vitalij Novickij
- Institute of High Magnetic Fields, Vilnius Gediminas Technical University, Vilnius, Lithuania
| | - Auksė Zinkevičienė
- Department of Immunology, State Research Institute Centre for Innovative Medicine, Vilnius, Lithuania
| | | | - Rūta Gruškienė
- Department of Chemistry and Bioengineering, Vilnius Gediminas Technical University, Vilnius, Lithuania
| | - Elena Servienė
- Laboratory of Genetics, Nature Research Centre, Vilnius, Lithuania.,Department of Chemistry and Bioengineering, Vilnius Gediminas Technical University, Vilnius, Lithuania
| | | | - Tatjana Krivorotova
- Department of Chemistry and Bioengineering, Vilnius Gediminas Technical University, Vilnius, Lithuania.,Institute of Chemistry, Vilnius University, Vilnius, Lithuania
| | - Eglė Lastauskienė
- Institute of Biosciences, Life Sciences Centre, Vilnius University, Vilnius, Lithuania
| | - Jolanta Sereikaitė
- Department of Chemistry and Bioengineering, Vilnius Gediminas Technical University, Vilnius, Lithuania
| | - Irutė Girkontaitė
- Department of Immunology, State Research Institute Centre for Innovative Medicine, Vilnius, Lithuania
| | - Jurij Novickij
- Institute of High Magnetic Fields, Vilnius Gediminas Technical University, Vilnius, Lithuania.,Institute for Telecommunications, Vilnius Gediminas Technical University, Vilnius, Lithuania
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10
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Li C, Ke Q, Yao C, Mi Y, Liu H, Lv Y, Yao C. Cell electrofusion based on nanosecond/microsecond pulsed electric fields. PLoS One 2018; 13:e0197167. [PMID: 29795594 PMCID: PMC5967737 DOI: 10.1371/journal.pone.0197167] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Accepted: 04/27/2018] [Indexed: 11/19/2022] Open
Abstract
Traditionally, microsecond pulsed electric field was widely used in cell electrofusion technology. However, it was difficult to fuse the cells with different sizes. Because the effect of electroporation based on microsecond pulses was greatly influenced by cell sizes. It had been reported that the differences between cell sizes can be ignored when cells were exposed to nanosecond pulses. However, pores induced by those short nanosecond pulses tended to be very small (0.9 nm) and the pores were more easy to recover. In this work, a finite element method was used to simulate the distribution, radius and density of the pores. The innovative idea of "cell electrofusion based on nanosecond/microsecond pulses" was proposed in order to combine the advantages of nanosecond pulses and microsecond pulses. The model consisted of two contact cells with different sizes. Three kinds of pulsed electric fields were made up of two 100-ns, 10-kV/cm pulses; two 10-μs, 1-kV/cm pulses; and a sequence of a 100-ns, 10-kV/cm pulse, followed by a 10-μs, 1-kV/cm pulse. Some obvious advantageous can be found when nanosecond/microsecond pulses were considered. The pore radius was large enough (70nm) and density was high (5×1013m-2) in the cell junction area. Moreover, pores in the non-contact area of the cell membrane were small (1-10 nm) and sparse (109-1012m-2). Areas where the transmembrane voltage was higher than 1V were only concentrated in the cell junction. The transmembrane voltage of other areas were at most 0.6V when we tested the rest of the cell membrane. Cell fusion efficiency can be improved remarkably because electroporation was concentrated in the cell contact area.
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Affiliation(s)
- Chengxiang Li
- The State Key Laboratory of Power Transmission Equipment & System Security and New Technology, School of Electrical Engineering, Chongqing University, Chongqing, China
| | - Qiang Ke
- The State Key Laboratory of Power Transmission Equipment & System Security and New Technology, School of Electrical Engineering, Chongqing University, Chongqing, China
| | - Chenguo Yao
- The State Key Laboratory of Power Transmission Equipment & System Security and New Technology, School of Electrical Engineering, Chongqing University, Chongqing, China
| | - Yan Mi
- The State Key Laboratory of Power Transmission Equipment & System Security and New Technology, School of Electrical Engineering, Chongqing University, Chongqing, China
| | - Hongmei Liu
- The State Key Laboratory of Power Transmission Equipment & System Security and New Technology, School of Electrical Engineering, Chongqing University, Chongqing, China
| | - Yanpeng Lv
- The State Key Laboratory of Power Transmission Equipment & System Security and New Technology, School of Electrical Engineering, Chongqing University, Chongqing, China
| | - Cheng Yao
- The State Key Laboratory of Power Transmission Equipment & System Security and New Technology, School of Electrical Engineering, Chongqing University, Chongqing, China
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11
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Novickij V, Stanevičienė R, Vepštaitė-Monstavičė I, Gruškienė R, Krivorotova T, Sereikaitė J, Novickij J, Servienė E. Overcoming Antimicrobial Resistance in Bacteria Using Bioactive Magnetic Nanoparticles and Pulsed Electromagnetic Fields. Front Microbiol 2018; 8:2678. [PMID: 29375537 PMCID: PMC5767227 DOI: 10.3389/fmicb.2017.02678] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Accepted: 12/22/2017] [Indexed: 11/21/2022] Open
Abstract
Nisin is a known bacteriocin, which exhibits a wide spectrum of antimicrobial activity, while commonly being inefficient against Gram-negative bacteria. In this work, we present a proof of concept of novel antimicrobial methodology using targeted magnetic nisin-loaded nano-carriers [iron oxide nanoparticles (NPs) (11-13 nm) capped with citric, ascorbic, and gallic acids], which are activated by high pulsed electric and electromagnetic fields allowing to overcome the nisin-resistance of bacteria. As a cell model the Gram-positive bacteria Bacillus subtilis and Gram-negative Escherichia coli were used. We have applied 10 and 30 kV cm-1 electric field pulses (100 μs × 8) separately and in combination with two pulsed magnetic field protocols: (1) high dB/dt 3.3 T × 50 and (2) 10 mT, 100 kHz, 2 min protocol to induce additional permeabilization and local magnetic hyperthermia. We have shown that the high dB/dt pulsed magnetic fields increase the antimicrobial efficiency of nisin NPs similar to electroporation or magnetic hyperthermia methods and a synergistic treatment is also possible. The results of our work are promising for the development of new methods for treatment of the drug-resistant foodborne pathogens to minimize the risks of invasive infections.
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Affiliation(s)
- Vitalij Novickij
- Institute of High Magnetic Fields, Vilnius Gediminas Technical University, Vilnius, Lithuania
| | - Ramunė Stanevičienė
- Laboratory of Genetics, Institute of Botany, Nature Research Centre, Vilnius, Lithuania
| | | | - Rūta Gruškienė
- Department of Chemistry and Bioengineering, Vilnius Gediminas Technical University, Vilnius, Lithuania
| | | | - Jolanta Sereikaitė
- Department of Chemistry and Bioengineering, Vilnius Gediminas Technical University, Vilnius, Lithuania
| | - Jurij Novickij
- Institute of High Magnetic Fields, Vilnius Gediminas Technical University, Vilnius, Lithuania
| | - Elena Servienė
- Laboratory of Genetics, Institute of Botany, Nature Research Centre, Vilnius, Lithuania
- Department of Chemistry and Bioengineering, Vilnius Gediminas Technical University, Vilnius, Lithuania
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12
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Novickij V, Švedienė J, Paškevičius A, Markovskaja S, Girkontaitė I, Zinkevičienė A, Lastauskienė E, Novickij J. Pulsed electric field-assisted sensitization of multidrug-resistant Candida albicans to antifungal drugs. Future Microbiol 2017; 13:535-546. [PMID: 29227694 DOI: 10.2217/fmb-2017-0245] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM Determine the influence of pH on the inactivation efficiency of Candida albicans in pulsed electric fields (PEF) and evaluate the possibilities for sensitization of a drug-resistant strain to antifungal drugs. MATERIALS & METHODS The effects of PEF (2.5-25 kVcm-1) with fluconazole, terbinafine and naftifine were analyzed at a pH range of 3.0-9.0. Membrane permeabilization was determined by flow cytometry and propidium iodide. RESULTS PEF induced higher inactivation of C. albicans at low pH and increased sensitivity to terbinafine and naftifine to which the strain was initially resistant. Up to 5 log reduction in cell survival was achieved. CONCLUSION A proof of concept that electroporation can be used to sensitize drug-resistant microorganisms was presented, which is promising for treating biofilm-associated infections.
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Affiliation(s)
- Vitalij Novickij
- Institute of High Magnetic Fields, Vilnius Gediminas Technical University, Naugarduko St 41, 03227 Vilnius, Lithuania
| | - Jurgita Švedienė
- Laboratory of Biodeterioration Research, Nature Research Centre, Akademijos St 2, 08412 Vilnius, Lithuania
| | - Algimantas Paškevičius
- Laboratory of Biodeterioration Research, Nature Research Centre, Akademijos St 2, 08412 Vilnius, Lithuania.,Laboratory of Microbiology of the Centre of Laboratory Medicine, Vilnius University Hospital Santariškių Clinics, Santariškių St 2, 08661 Vilnius, Lithuania
| | - Svetlana Markovskaja
- Laboratory of Mycology, Nature Research Centre, Žaliųjų ežerų St 49, 08406 Vilnius, Lithuania
| | - Irutė Girkontaitė
- State Research Institute Centre for Innovative Medicine, Department of Immunology, Santariškių St 5, 08406 Vilnius, Lithuania
| | - Auksė Zinkevičienė
- State Research Institute Centre for Innovative Medicine, Department of Immunology, Santariškių St 5, 08406 Vilnius, Lithuania
| | - Eglė Lastauskienė
- Department of Microbiology & Biotechnology, Vilnius University, Sauletekio al. 7, 10257 Vilnius, Lithuania
| | - Jurij Novickij
- Institute of High Magnetic Fields, Vilnius Gediminas Technical University, Naugarduko St 41, 03227 Vilnius, Lithuania
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13
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Yao C, Lv Y, Zhao Y, Dong S, Liu H, Ma J. Synergistic combinations of short high-voltage pulses and long low-voltage pulses enhance irreversible electroporation efficacy. Sci Rep 2017; 7:15123. [PMID: 29123231 PMCID: PMC5680269 DOI: 10.1038/s41598-017-15494-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Accepted: 10/27/2017] [Indexed: 12/18/2022] Open
Abstract
Irreversible electroporation (IRE) uses ~100 μs pulsed electric fields to disrupt cell membranes for solid tumor ablation. Although IRE has achieved exciting preliminary clinical results, implementing IRE could be challenging because of volumetric limitations at the ablation region. Combining short high-voltage (SHV: 1600V, 2 μs, 1 Hz, 20 pulses) pulses with long low-voltage (LLV: 240-480 V, 100 μs, 1 Hz, 60-80 pulses) pulses induces a synergistic effect that enhances IRE efficacy. Here, cell cytotoxicity and tissue ablation were investigated. The results show that combining SHV pulses with LLV pulses induced SKOV3 cell death more effectively, and compared to either SHV pulses or LLV pulses applied alone, the combination significantly enhanced the ablation region. Particularly, prolonging the lag time (100 s) between SHV and LLV pulses further reduced cell viability and enhanced the ablation area. However, the sequence of SHV and LLV pulses was important, and the LLV + SHV combination was not as effective as the SHV + LLV combination. We offer a hypothesis to explain the synergistic effect behind enhanced cell cytotoxicity and enlarged ablation area. This work shows that combining SHV pulses with LLV pulses could be used as a focal therapy and merits investigation in larger pre-clinical models and microscopic mechanisms.
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Affiliation(s)
- Chenguo Yao
- The State Key Laboratory of Power Transmission Equipment and System Security and New Technology, the School of Electrical Engineering, Chongqing University, Chongqing, 400030, China.
| | - Yanpeng Lv
- The State Key Laboratory of Power Transmission Equipment and System Security and New Technology, the School of Electrical Engineering, Chongqing University, Chongqing, 400030, China.
| | - Yajun Zhao
- The State Key Laboratory of Power Transmission Equipment and System Security and New Technology, the School of Electrical Engineering, Chongqing University, Chongqing, 400030, China
| | - Shoulong Dong
- The State Key Laboratory of Power Transmission Equipment and System Security and New Technology, the School of Electrical Engineering, Chongqing University, Chongqing, 400030, China
| | - Hongmei Liu
- The State Key Laboratory of Power Transmission Equipment and System Security and New Technology, the School of Electrical Engineering, Chongqing University, Chongqing, 400030, China
| | - Jianhao Ma
- The State Key Laboratory of Power Transmission Equipment and System Security and New Technology, the School of Electrical Engineering, Chongqing University, Chongqing, 400030, China
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14
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Kandušer M, Belič A, Čorović S, Škrjanc I. Modular Serial Flow Through device for pulsed electric field treatment of the liquid samples. Sci Rep 2017; 7:8115. [PMID: 28808315 PMCID: PMC5556104 DOI: 10.1038/s41598-017-08620-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2016] [Accepted: 07/11/2017] [Indexed: 11/25/2022] Open
Abstract
In biotechnology, medicine, and food processing, simple and reliable methods for cell membrane permeabilization are required for drug/gene delivery into the cells or for the inactivation of undesired microorganisms. Pulsed electric field treatment is among the most promising methods enabling both aims. The drawback in current technology is controllable large volume operation. To address this challenge, we have developed an experimental setup for flow through electroporation with online regulation of the flow rate with feedback control. We have designed a modular serial flow-through co-linear chamber with a smooth inner surface, the uniform cross-section geometry through the majority of the system’s length, and the mesh in contact with the electrodes, which provides uniform electric field distribution and fluid velocity equilibration. The cylindrical cross-section of the chamber prevents arching at the active treatment region. We used mathematical modeling for the evaluation of electric field distribution and the flow profile in the active region. The system was tested for the inactivation of Escherichia coli. We compared two flow-through chambers and used a static chamber as a reference. The experiments were performed under identical experimental condition (product and similar process parameters). The data were analyzed in terms of inactivation efficiency and specific energy consumption.
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Affiliation(s)
- Maša Kandušer
- University of Ljubljana, Faculty of Electrical Engineering, Tržaška 25, SI-1000, Ljubljana, Slovenia
| | - Aleš Belič
- University of Ljubljana, Faculty of Electrical Engineering, Tržaška 25, SI-1000, Ljubljana, Slovenia
| | - Selma Čorović
- University of Ljubljana, Faculty of Electrical Engineering, Tržaška 25, SI-1000, Ljubljana, Slovenia
| | - Igor Škrjanc
- University of Ljubljana, Faculty of Electrical Engineering, Tržaška 25, SI-1000, Ljubljana, Slovenia.
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Yao C, Lv Y, Dong S, Zhao Y, Liu H. Irreversible electroporation ablation area enhanced by synergistic high- and low-voltage pulses. PLoS One 2017; 12:e0173181. [PMID: 28253331 PMCID: PMC5333894 DOI: 10.1371/journal.pone.0173181] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Accepted: 02/16/2017] [Indexed: 11/18/2022] Open
Abstract
Irreversible electroporation (IRE) produced by a pulsed electric field can ablate tissue. In this study, we achieved an enhancement in ablation area by using a combination of short high-voltage pulses (HVPs) to create a large electroporated area and long low-voltage pulses (LVPs) to ablate the electroporated area. The experiments were conducted in potato tuber slices. Slices were ablated with an array of four pairs of parallel steel electrodes using one of the following four electric pulse protocols: HVP, LVP, synergistic HVP+LVP (SHLVP) or LVP+HVP. Our results showed that the SHLVPs more effectively necrotized tissue than either the HVPs or LVPs, even when the SHLVP dose was the same as or lower than the HVP or LVP doses. The HVP and LVP order mattered and only HVPs+LVPs (SHLVPs) treatments increased the size of the ablation zone because the HVPs created a large electroporated area that was more susceptible to the subsequent LVPs. Real-time temperature change monitoring confirmed that the tissue was non-thermally ablated by the electric pulses. Theoretical calculations of the synergistic effects of the SHLVPs on tissue ablation were performed. Our proposed SHLVP protocol provides options for tissue ablation and may be applied to optimize the current clinical IRE protocols.
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Affiliation(s)
- Chenguo Yao
- The State Key Laboratory of Power Transmission Equipment & System Security and New Technology, School of Electrical Engineering, Chongqing University, Chongqing, China
- * E-mail:
| | - Yanpeng Lv
- The State Key Laboratory of Power Transmission Equipment & System Security and New Technology, School of Electrical Engineering, Chongqing University, Chongqing, China
| | - Shoulong Dong
- The State Key Laboratory of Power Transmission Equipment & System Security and New Technology, School of Electrical Engineering, Chongqing University, Chongqing, China
| | - Yajun Zhao
- The State Key Laboratory of Power Transmission Equipment & System Security and New Technology, School of Electrical Engineering, Chongqing University, Chongqing, China
| | - Hongmei Liu
- The State Key Laboratory of Power Transmission Equipment & System Security and New Technology, School of Electrical Engineering, Chongqing University, Chongqing, China
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Novickij V, Stanevičienė R, Grainys A, Lukša J, Badokas K, Krivorotova T, Sereikaitė J, Novickij J, Servienė E. Electroporation-assisted inactivation of Escherichia coli using nisin-loaded pectin nanoparticles. INNOV FOOD SCI EMERG 2016. [DOI: 10.1016/j.ifset.2016.09.019] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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17
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Garner AL, Neculaes VB, Deminsky M, Dylov DV, Joo C, Loghin ER, Yazdanfar S, Conway KR. Plasma membrane temperature gradients and multiple cell permeabilization induced by low peak power density femtosecond lasers. Biochem Biophys Rep 2015; 5:168-174. [PMID: 28955820 PMCID: PMC5598230 DOI: 10.1016/j.bbrep.2015.11.019] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Revised: 11/01/2015] [Accepted: 11/18/2015] [Indexed: 02/02/2023] Open
Abstract
Calculations indicate that selectively heating the extracellular media induces membrane temperature gradients that combine with electric fields and a temperature-induced reduction in the electropermeabilization threshold to potentially facilitate exogenous molecular delivery. Experiments by a wide-field, pulsed femtosecond laser with peak power density far below typical single cell optical delivery systems confirmed this hypothesis. Operating this laser in continuous wave mode at the same average power permeabilized many fewer cells, suggesting that bulk heating alone is insufficient and temperature gradients are crucial for permeabilization. This work suggests promising opportunities for a high throughput, low cost, contactless method for laser mediated exogenous molecule delivery without the complex optics of typical single cell optoinjection, for potential integration into microscope imaging and microfluidic systems. Femtosecond lasers can transfect a single cell through optoporation. Multiple cells are transfected with much lower power densities at 1550 nm. Calculations show that temperature gradients contribute to the mechanism. These mechanisms resemble those also involved in microwave biological interactions.
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Affiliation(s)
- Allen L Garner
- School of Nuclear Engineering, Purdue University, West Lafayette, IN 47907, USA
| | - V Bogdan Neculaes
- GE Global Research Center, 1 Research Circle, Niskayuna, NY 12309, USA
| | - Maxim Deminsky
- Kintech LTD, Kurchatov sq. 1, 123182 Moscow, Russia.,NRC "Kurchatov Institute", Kurchatov sq. 1, 123182 Moscow, Russia
| | - Dmitry V Dylov
- GE Global Research Center, 1 Research Circle, Niskayuna, NY 12309, USA
| | - Chulmin Joo
- School of Mechanical Engineering, Yonsei University, Seoul 120-749, South Korea
| | - Evelina R Loghin
- GE Global Research Center, 1 Research Circle, Niskayuna, NY 12309, USA
| | - Siavash Yazdanfar
- GE Global Research Center, 1 Research Circle, Niskayuna, NY 12309, USA
| | - Kenneth R Conway
- GE Global Research Center, 1 Research Circle, Niskayuna, NY 12309, USA
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Haberl Meglic S, Marolt T, Miklavcic D. Protein Extraction by Means of Electroporation from E. coli with Preserved Viability. J Membr Biol 2015. [PMID: 26201287 DOI: 10.1007/s00232-015-9824-7] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Extracting proteins by means of electroporation from different microorganisms is gaining on its importance, as electroporation is a quick, chemical-free, and cost-effective method. Since complete cell destruction (to obtain proteins) necessitates additional work, and cost of purifying the end-product is high, pulses have to be adjusted in order to prevent total disintegration. Namely, total disintegration of the cell releases bacterial membrane contaminants in the final sample. Therefore, our goal was to study different electric pulse parameters in order to extract as much proteins as possible from E. coli bacteria, while preserving bacterial viability. Our results show that by increasing electric field strength the concentration of extracted proteins increases and viability reduces. The correlation is reasonable, since high electric field destroys bacterial envelope, releasing all intracellular components into surrounding media. The strong correlation was also found with pulse duration. However, at longer pulses we obtained more proteins, while bacterial viability was not as much affected. Pulse number and/or pulse repetition frequency at our conditions have no or little effect on concentration of extracted proteins and/or bacterial viability. We can conclude that the most promising pulse protocol for protein extraction by means of electroporation based on our experience would be longer pulses with lower pulse amplitude assuring high protein yield and low effect on bacterial viability.
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Affiliation(s)
- Sasa Haberl Meglic
- Laboratory of Biocybernetics, Faculty of Electrical Engineering, University of Ljubljana, Trzaska 25, 1000, Ljubljana, Slovenia
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19
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Chopinet L, Rols MP. Nanosecond electric pulses: A mini-review of the present state of the art. Bioelectrochemistry 2015; 103:2-6. [DOI: 10.1016/j.bioelechem.2014.07.008] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2014] [Revised: 07/20/2014] [Accepted: 07/24/2014] [Indexed: 01/08/2023]
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20
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Guionet A, David F, Zaepffel C, Coustets M, Helmi K, Cheype C, Packan D, Garnier JP, Blanckaert V, Teissié J. E. coli electroeradication on a closed loop circuit by using milli-, micro- and nanosecond pulsed electric fields: Comparison between energy costs. Bioelectrochemistry 2015; 103:65-73. [DOI: 10.1016/j.bioelechem.2014.08.021] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2014] [Revised: 07/25/2014] [Accepted: 08/12/2014] [Indexed: 01/30/2023]
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21
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Flisar K, Meglic SH, Morelj J, Golob J, Miklavcic D. Testing a prototype pulse generator for a continuous flow system and its use for E. coli inactivation and microalgae lipid extraction. Bioelectrochemistry 2014; 100:44-51. [DOI: 10.1016/j.bioelechem.2014.03.008] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2013] [Revised: 02/26/2014] [Accepted: 03/18/2014] [Indexed: 12/30/2022]
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22
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Bonetta S, Bonetta S, Bellero M, Pizzichemi M, Carraro E. Inactivation of Escherichia coli and Staphylococcus aureus by pulsed electric fields increases with higher bacterial population and with agitation of liquid medium. J Food Prot 2014; 77:1219-23. [PMID: 24988033 DOI: 10.4315/0362-028x.jfp-13-487] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Inactivation of Escherichia coli, E. coli O157:H7, and Staphylococcus aureus in liquid media by pulsed electric fields (PEF) was conducted at varying bacterial populations with and without sample agitation. A laboratory-scale PEF batch unit with a rectangular electric pulse was used, operating under the following conditions: 25 kV/cm (E. coli, E. coli O157:H7) and 30 kV/cm (S. aureus) electric field strengths, 1-μs pulse width, 1-Hz pulse repetition rate, and 20 to 350 pulses for all samples. Not surprisingly, bacterial inactivation (for all three strains) increased with increasing pulse number, achieving the highest reduction at 350 pulses. Log CFU per milliliter microbial inactivation increased commensurately with increasing bacterial population (P < 0.05) but only when samples were treated with more than 200 pulses. For example, when E. coli was treated with 200 pulses at 10(5) CFU/ml, inactivation was only 3.0 Log versus 4.8 Log at the 10(10) inoculation level. When E. coli O157:H7 was treated with 200 pulses at 10(5) CFU/ml, inactivation was only 2.5 Log versus 4.6 Log at the 10(10) inoculation level. When S. aureus was treated with 200 pulses at 10(6) CFU/ml, inactivation was only 2.6 Log versus 4.8 Log at the 10(10) inoculation level. Inactivation of populations was also found to be statistically greater (P < 0.05) when liquid samples were agitated, in comparison to nonagitated samples. Because PEF inactivation activity is influenced by bacterial population and sample agitation, future studies should carefully consider these factors in experimental designs and/or scaled-up industry application.
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Affiliation(s)
- Silvia Bonetta
- Dipartimento di Scienze ed Innovazione Tecnologica, Università del Piemonte Orientale A. Avogadro, Viale T. Michel 11, 15121 Alessandria, Italy
| | - Sara Bonetta
- Dipartimento di Scienze della Sanità Pubblica e Pediatriche, Università di Torino, Piazza Polonia 94, 10126 Torino, Italy
| | - Monica Bellero
- Dipartimento di Scienze ed Innovazione Tecnologica, Università del Piemonte Orientale A. Avogadro, Viale T. Michel 11, 15121 Alessandria, Italy
| | - Marco Pizzichemi
- Dipartimento di Fisica G. Occhialini, Università di Milano Bicocca, Piazza della Scienza 3, 20126 Milano, Italy
| | - Elisabetta Carraro
- Dipartimento di Scienze della Sanità Pubblica e Pediatriche, Università di Torino, Piazza Polonia 94, 10126 Torino, Italy.
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23
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Guionet A, Joubert-Durigneux V, Packan D, Cheype C, Garnier JP, David F, Zaepffel C, Leroux RM, Teissié J, Blanckaert V. Effect of nanosecond pulsed electric field on Escherichia coli
in water: inactivation and impact on protein changes. J Appl Microbiol 2014; 117:721-8. [DOI: 10.1111/jam.12558] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2014] [Revised: 05/23/2014] [Accepted: 05/29/2014] [Indexed: 11/29/2022]
Affiliation(s)
- A. Guionet
- VERI; Chemin de la Digue; Maisons Lafitte France
- CNRS UMR5089 - IPBS (Institut de Pharmacologie et de Biologie Structurale); Toulouse France
- Université de Toulouse; UPS; IPBS; Toulouse France
| | | | - D. Packan
- ONERA; DMPH; Chemin de la Hunière; Palaiseau France
| | - C. Cheype
- CERPEM; Laval Mayenne Technopole; Laval France
| | | | - F. David
- VERI; Chemin de la Digue; Maisons Lafitte France
| | - C. Zaepffel
- ONERA; DMPH; Chemin de la Hunière; Palaiseau France
| | - R.-M. Leroux
- Mer, Molécules, Santé; IUML-FR 3473 CNRS, Université du Maine; IUT de Laval; Département Génie Biologique, Laval France
| | - J. Teissié
- CNRS UMR5089 - IPBS (Institut de Pharmacologie et de Biologie Structurale); Toulouse France
- Université de Toulouse; UPS; IPBS; Toulouse France
| | - V. Blanckaert
- Mer, Molécules, Santé; IUML-FR 3473 CNRS, Université du Maine; IUT de Laval; Département Génie Biologique, Laval France
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González-Sosa J, Ruiz-Vargas A, Arias G, Ivorra A. Fast flow-through non-thermal pasteurization using constant radiofrequency electric fields. INNOV FOOD SCI EMERG 2014. [DOI: 10.1016/j.ifset.2014.01.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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25
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Haberl S, Jarc M, Štrancar A, Peterka M, Hodžić D, Miklavčič D. Comparison of Alkaline Lysis with Electroextraction and Optimization of Electric Pulses to Extract Plasmid DNA from Escherichia coli. J Membr Biol 2013; 246:861-7. [DOI: 10.1007/s00232-013-9580-5] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2013] [Accepted: 06/22/2013] [Indexed: 12/20/2022]
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26
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Frey W, Gusbeth C, Schwartz T. Inactivation of Pseudomonas putida by pulsed electric field treatment: a study on the correlation of treatment parameters and inactivation efficiency in the short-pulse range. J Membr Biol 2013; 246:769-81. [PMID: 23660812 DOI: 10.1007/s00232-013-9547-6] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2012] [Accepted: 04/17/2013] [Indexed: 01/19/2023]
Abstract
An important issue for an economic application of the pulsed electric field treatment for bacterial decontamination of wastewater is the specific treatment energy needed for effective reduction of bacterial populations. The present experimental study performed in a field amplitude range of 40 > E > 200 kV/cm and for a suspension conductivity of 0.01 = κ(e) > 0.2 S/m focusses on the application of short pulses, 25 ns > T > 10 μs, of rectangular, bipolar and exponential shape and was made on Pseudomonas putida, which is a typical and widespread wastewater microorganism. The comparison of inactivation results with calculations of the temporal and azimuthal membrane charging dynamics using the model of Pauly and Schwan revealed that for efficient inactivation, membrane segments at the cell equator have to be charged quickly and to a sufficiently high value, on the order of 0.5 V. After fulfilling this basic condition by an appropriate choice of pulse field strength and duration, the log rate of inactivation for a given suspension conductivity of 0.2 S/m was found to be independent of the duration of individual pulses for constant treatment energy expenditure. Moreover, experimental results suggest that even pulse shape plays a minor role in inactivation efficiency. The variation of the suspension conductivity resulted in comparable inactivation performance of identical pulse parameters if the product of pulse duration and number of pulses was the same, i.e., required treatment energy can be linearly downscaled for lower conductivities, provided that pulse amplitude and duration are selected for entire membrane surface permeabilization.
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Affiliation(s)
- Wolfgang Frey
- Institute for Pulsed Power and Microwave Technology, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, Eggenstein-Leopoldshafen, 76344, Germany,
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