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Zare F, Ghasemi N, Bansal N, Hosano H. Advances in pulsed electric stimuli as a physical method for treating liquid foods. Phys Life Rev 2023; 44:207-266. [PMID: 36791571 DOI: 10.1016/j.plrev.2023.01.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Accepted: 01/28/2023] [Indexed: 02/05/2023]
Abstract
There is a need for alternative technologies that can deliver safe and nutritious foods at lower costs as compared to conventional processes. Pulsed electric field (PEF) technology has been utilised for a plethora of different applications in the life and physical sciences, such as gene/drug delivery in medicine and extraction of bioactive compounds in food science and technology. PEF technology for treating liquid foods involves engineering principles to develop the equipment, and quantitative biochemistry and microbiology techniques to validate the process. There are numerous challenges to address for its application in liquid foods such as the 5-log pathogen reduction target in food safety, maintaining the food quality, and scale up of this physical approach for industrial integration. Here, we present the engineering principles associated with pulsed electric fields, related inactivation models of microorganisms, electroporation and electropermeabilization theory, to increase the quality and safety of liquid foods; including water, milk, beer, wine, fruit juices, cider, and liquid eggs. Ultimately, we discuss the outlook of the field and emphasise research gaps.
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Affiliation(s)
- Farzan Zare
- School of Information Technology and Electrical Engineering, The University of Queensland, Brisbane, St Lucia QLD 4072, Australia; School of Agriculture and Food Sciences, The University of Queensland, St Lucia QLD 4072, Australia
| | - Negareh Ghasemi
- School of Information Technology and Electrical Engineering, The University of Queensland, Brisbane, St Lucia QLD 4072, Australia
| | - Nidhi Bansal
- School of Agriculture and Food Sciences, The University of Queensland, St Lucia QLD 4072, Australia
| | - Hamid Hosano
- Biomaterials and Bioelectrics Department, Institute of Industrial Nanomaterials, Kumamoto University, Kumamoto 860-8555, Japan.
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Effect of pH on Escherichia coli Removal by Electrocoagulation and Elimination Kinetics after Treatment. J CHEM-NY 2022. [DOI: 10.1155/2022/5249368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
There are different techniques for removing microorganisms in wastewater, each with its own advantages and disadvantages. Electrocoagulation because of its simplicity has gained great attention and is used for the removal of various ions, organic matters, and microorganisms. In this study, the effectiveness and mechanism of Escherichia coli (E. coli) removal by electrocoagulation process using aluminum and ordinary steel electrodes at different initial-pH and the kinetics of elimination of E. coli in solution after treatment were investigated. Artificial wastewater contaminated by E. coli culture was used in the experiments. The results show that the initial-pH influences significantly the effectiveness of E. coli removal. Under the experimental conditions used, more than 5 log removal of E. coli is obtained, irrespective of the nature of the electrode (ordinary steel or aluminum) and the value of the initial pH. On the one hand, the best rates of elimination are obtained for solutions that are slightly acidic (pH 5.5) and for an alkaline pH (8.5 and 10). On the other hand, the elimination decreases for a neutral solution and for a very acidic solution (pH 2.9) because of the strong resistance developed by E. coli at those pH values. For optimal treatment, the choice of electrode material depends on the initial pH. Furthermore, the study of the kinetics of elimination of E. coli after treatment shows the remanent power of the electrocoagulation process. It allows reducing treatment time and energy consumption, thus reducing the cost of treatment.
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Characterization of damage on Listeria innocua surviving to pulsed light: Effect on growth, DNA and proteome. Int J Food Microbiol 2018; 284:63-72. [PMID: 30005928 DOI: 10.1016/j.ijfoodmicro.2018.07.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Revised: 05/25/2018] [Accepted: 07/02/2018] [Indexed: 11/23/2022]
Abstract
The effect of pulsed light treatment on the lag phase and the maximum specific growth rate of Listeria innocua was determined in culture media at 7 °C. Fluences of 0.175, 0.350 and 0.525 J/cm2 were tested. The lag phase of the survivors increased as fluence did, showing significant differences for all the doses; an 8.7-fold increase was observed at 0.525 J/cm2. Pulsed light decreased the maximum specific growth rate by 38% at the same fluence. Both parameters were also determined by time-lapse microscopy at 25 °C in survivors to 0.525 J/cm2, with an increase of 13-fold of the lag phase and a 45% decrease of the maximum specific growth rate. The higher the fluence, the higher the variability of both parameters was. To characterize pulsed light damage on L. innocua, the formation of dimers on DNA was assessed, and a proteomic study was undertaken. In cells treated with 0.525 J/cm2, cyclobutane pyrimidine dimers and pyrimidine (6-4) pyrimidone photoproducts were detected at 5:1 ratio. Pulsed light induced the expression of three proteins, among them the general stress protein Ctc. Furthermore, treated cells showed an up-regulation of proteins related to metabolism of nucleotides and fatty acids, as well as with translation processes, whereas flagellin and some glucose metabolism proteins were down-regulated. Differences in the proteome of the survivors could contribute to explain the mechanisms of adaptation of L. innocua after pulsed light treatment.
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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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Wang LH, Wang MS, Zeng XA, Liu ZW. Temperature-mediated variations in cellular membrane fatty acid composition of Staphylococcus aureus in resistance to pulsed electric fields. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2016; 1858:1791-800. [DOI: 10.1016/j.bbamem.2016.05.003] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Revised: 04/25/2016] [Accepted: 05/03/2016] [Indexed: 10/21/2022]
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Aguirre JS, de Fernando GG, Hierro E, Hospital XF, Ordóñez JA, Fernández M. Estimation of the growth kinetic parameters of Bacillus cereus spores as affected by pulsed light treatment. Int J Food Microbiol 2015; 202:20-6. [DOI: 10.1016/j.ijfoodmicro.2015.02.020] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2014] [Revised: 12/22/2014] [Accepted: 02/18/2015] [Indexed: 10/23/2022]
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Walkling-Ribeiro M, Anany H, Griffiths MW. Effect of heat-assisted pulsed electric fields and bacteriophage on enterohemorrhagic Escherichia coli O157:H7. Biotechnol Prog 2014; 31:110-8. [PMID: 25376158 DOI: 10.1002/btpr.2014] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2014] [Revised: 10/28/2014] [Indexed: 01/21/2023]
Abstract
Pulsed electric fields (PEF), heat-assisted PEF (H-PEF), and virulent bacteriophage (VP) are non-thermal techniques for pathogen inactivation in liquids that were investigated individually, and in combination (PEF/VP, H-PEF/VP) to control enterohemorrhagic Escherichia coli (EHEC) O157:H7 in Luria-Bertani broth (LBB) and Ringer's solution (RS). Treated cells were subsequently incubated at refrigeration (4°C) and temperature-abuse conditions (12°C) for 5 days. When EHEC cells grown in LBB were subjected to non-thermal processing and subsequently stored at 12°C for 5 days, reductions in count of between 0.1 and 0.6 log cycles were observed and following storage at 4°C the decrease in counts varied between 0.2 and 1.1 log10 . For bacteria cells suspended in RS values ranged from 0.1 to ≥3.9 log cycles at both storage temperatures. The most effective treatments were H-PEF and H-PEF/VP, both producing a >3.4 log cycle reduction of cells suspended in non-nutrient RS. Analysis of EHEC recovery on selective and non-selective media indicated no occurrence of sub-lethal damage for VP, PEF/VP, and H-PEF/VP-treated cells. The findings indicate that combining PEF and lytic phage may represent a suitable alternative to conventional fluid decontamination following further process optimization.
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Affiliation(s)
- Markus Walkling-Ribeiro
- Dept. of Food Science, Canadian Research Inst. for Food Safety, University of Guelph, Guelph, ON, Canada, N1G 2W1; Dept. of Food Science, Cornell University, Ithaca, NY, 14853
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The effect of non-thermal processing technologies on microbial inactivation: An investigation into sub-lethal injury of Escherichia coli and Pseudomonas fluorescens. Food Control 2014. [DOI: 10.1016/j.foodcont.2014.01.011] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Halpin R, Cregenzán-Alberti O, Whyte P, Lyng J, Noci F. Combined treatment with mild heat, manothermosonication and pulsed electric fields reduces microbial growth in milk. Food Control 2013. [DOI: 10.1016/j.foodcont.2013.05.008] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Rivas A, Pina-Pérez M, Rodriguez-Vargas S, Zuñiga M, Martinez A, Rodrigo D. Sublethally damaged cells of Escherichia coli by Pulsed Electric Fields: The chance of transformation and proteomic assays. Food Res Int 2013. [DOI: 10.1016/j.foodres.2013.01.014] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Cocoa powder as a natural ingredient revealing an enhancing effect to inactivate Cronobacter sakazakii cells treated by Pulsed Electric Fields in infant milk formula. Food Control 2013. [DOI: 10.1016/j.foodcont.2012.11.014] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Seratlić S, Bugarski B, Nedović V, Radulović Z, Wadsö L, Dejmek P, Galindo FG. Behavior of the surviving population of Lactobacillus plantarum 564 upon the application of pulsed electric fields. INNOV FOOD SCI EMERG 2013. [DOI: 10.1016/j.ifset.2012.11.011] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Aguirre J, Rodríguez MR, González R, García de Fernando G. E-beam irradiation affects the maximum specific growth rate ofBacillus cereus. Int J Food Sci Technol 2012. [DOI: 10.1111/j.1365-2621.2012.03199.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Juan Aguirre
- Dpto. de Nutrición; Bromatología y Tecnología de los Alimentos; Facultad de Veterinaria; Universidad Complutense de Madrid; Ciudad Universitaria; 28040; Madrid; Spain
| | - Mª Rosa Rodríguez
- Dpto. de Nutrición; Bromatología y Tecnología de los Alimentos; Facultad de Veterinaria; Universidad Complutense de Madrid; Ciudad Universitaria; 28040; Madrid; Spain
| | - Rodrigo González
- Dpto. de Nutrición; Bromatología y Tecnología de los Alimentos; Facultad de Veterinaria; Universidad Complutense de Madrid; Ciudad Universitaria; 28040; Madrid; Spain
| | - Gonzalo García de Fernando
- Dpto. de Nutrición; Bromatología y Tecnología de los Alimentos; Facultad de Veterinaria; Universidad Complutense de Madrid; Ciudad Universitaria; 28040; Madrid; Spain
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Aguirre JS, Ordóñez JA, García de Fernando GD. A comparison of the effects of E-beam irradiation and heat treatment on the variability of Bacillus cereus inactivation and lag phase duration of surviving cells. Int J Food Microbiol 2012; 153:444-52. [DOI: 10.1016/j.ijfoodmicro.2011.12.012] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2011] [Revised: 12/07/2011] [Accepted: 12/11/2011] [Indexed: 10/14/2022]
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Rodríguez-González O, Walkling-Ribeiro M, Jayaram S, Griffiths MW. Cross-protective effects of temperature, pH, and osmotic and starvation stresses in Escherichia coli O157:H7 subjected to pulsed electric fields in milk. Int Dairy J 2011. [DOI: 10.1016/j.idairyj.2011.07.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Arroyo C, Somolinos M, Cebrián G, Condón S, Pagán R. Pulsed electric fields cause sublethal injuries in the outer membrane of Enterobacter sakazakii facilitating the antimicrobial activity of citral. Lett Appl Microbiol 2011; 51:525-31. [PMID: 21039664 DOI: 10.1111/j.1472-765x.2010.02931.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
AIMS The objective was to evaluate the relation of sublethal injury in the outer membrane of Enterobacter sakazakii to the inactivating effect of the combination of pulsed electric fields (PEF) treatments and citral. METHODS AND RESULTS The occurrence of sublethal injury in the outer membrane was measured using selective recovery media containing bile salts. Loss of membrane integrity was measured by the increased uptake of the fluorescent dye propidium iodide (PI). PEF caused nonpermanent and permanent envelope permeabilization of Ent. sakazakii at pH 4·0. After PEF, most surviving cells showed transient cell permeabilization and sublethal injury in their outer membranes. The simultaneous application of a mild PEF treatment (100 pulses, 25 kV cm(-1) ) and 200 μl l(-1) of citral to cells suspended in pH 4·0 buffer at a final concentration of 10(7) cells per ml showed an outstanding synergistic lethal effect, causing the inactivation of more than two extra log(10) cycles. CONCLUSIONS Our results confirm that the detection of sublethal injury in the outer membrane after PEF may contribute to the identification of the treatment conditions under which PEF may act synergistically with hydrophobic compounds such as citral. SIGNIFICANCE AND IMPACT OF THE STUDY Knowledge about the mechanism of microbial inactivation by PEF will aid the establishment of successful combined preservation treatments.
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Affiliation(s)
- C Arroyo
- Tecnología de los Alimentos, Universidad de Zaragoza, Zaragoza, Spain
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Condón S, Mañas P, Cebrián G. Manothermosonication for Microbial Inactivation. FOOD ENGINEERING SERIES 2011. [DOI: 10.1007/978-1-4419-7472-3_11] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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Arroyo C, Somolinos M, Cebrián G, Condón S, Pagán R. Pulsed electric fields cause sublethal injuries in the outer membrane of Enterobacter sakazakii facilitating the antimicrobial activity of citral. Lett Appl Microbiol 2010. [DOI: 10.1111/j.0266-8254.2010.02931.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Arroyo C, Cebrián G, Pagán R, Condón S. Resistance of Enterobacter sakazakii to pulsed electric fields. INNOV FOOD SCI EMERG 2010. [DOI: 10.1016/j.ifset.2009.11.002] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Influence of partial inactivation on growth of Listeria monocytogenes under sub-optimal conditions of increased NaCl concentration or increased acidity. INNOV FOOD SCI EMERG 2009. [DOI: 10.1016/j.ifset.2008.11.011] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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21
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Jin T, Zhang H, Hermawan N, Dantzer W. Effects of pH and temperature on inactivation ofSalmonella typhimuriumDT104 in liquid whole egg by pulsed electric fields. Int J Food Sci Technol 2009. [DOI: 10.1111/j.1365-2621.2008.01759.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Zhao W, Yang R, Wang M. Cold storage temperature following pulsed electric fields treatment to inactivate sublethally injured microorganisms and extend the shelf life of green tea infusions. Int J Food Microbiol 2009; 129:204-8. [DOI: 10.1016/j.ijfoodmicro.2008.12.006] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2008] [Revised: 11/23/2008] [Accepted: 12/02/2008] [Indexed: 11/29/2022]
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Walkling-Ribeiro M, Noci F, Cronin D, Lyng J, Morgan D. Inactivation ofEscherichia coliin a Tropical Fruit Smoothie by a Combination of Heat and Pulsed Electric Fields. J Food Sci 2008; 73:M395-9. [DOI: 10.1111/j.1750-3841.2008.00927.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Dai QW, Dong FQ, Deng JJ. Effect of low-voltage static electric field on growth of Esoherichia coli. Shijie Huaren Xiaohua Zazhi 2006; 14:682-686. [DOI: 10.11569/wcjd.v14.i7.682] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To study the influence of static electric field with different intensities on the growth of Esoherichia coli.
METHODS: The static electric field of 3 and 24 volt were used upon the big tubes (Ф = 30 mm) in which E. coli were cultured. The optical density and bacterial colony numbers were measured during the growth process of E. coli. Meanwhile, the morphology of E. coli under the action of 24-volt static electric field was observed by scanning electron microscopy (SEM) comparatively analyzed with the control group.
RESULTS: The growth of E. coli obviously restrained during the prophase of culturing under the experiment conditions. Stable growth period of E. coli was advanced 2 and 4 hours under the action of static electric fields of 3 and 24 volt, respectively. E. coli appeared the second logarithm growth period 6-8 h after the first stable period started. That was the growth remediation of bacteria. And in the experimental conditions, the intensity of static electric field was in inverse relation with the restoring speed of E. coli. In addition, the morphological distortion of E. coli was found under the SEM.
CONCLUSION: The external low-voltage static electric field has inhibitory effect on the growth of E. coli.
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García D, Mañas P, Gómez N, Raso J, Pagán R. Biosynthetic requirements for the repair of sublethal membrane damage in Escherichia coli cells after pulsed electric fields. J Appl Microbiol 2006; 100:428-35. [PMID: 16478482 DOI: 10.1111/j.1365-2672.2005.02795.x] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
AIMS The aim was to evaluate the biosynthetic requirements for the repair of sublethal membrane damages in Escherichia coli cells after exposure to pulsed electric fields (PEF). METHODS AND RESULTS The partial loss of the barrier and homeostatic functions of the cytoplasmic membrane was examined by adding sodium chloride to the recovery media. More than 4 log10 cycles of survivors were sublethally injured after PEF. Repair of such sublethal membrane damages occurred when survivors to PEF were incubated in peptone water for 2 h. Two different types of sublethally injured cells were detected. Whereas a small proportion (<5%) repaired after PEF in less than 2 min, the repair of the remaining 95% injured cells lasted 2 h and was dependent on biosynthetic requirements. The addition of inhibitors such as chloramphenicol, cerulenin, penicillin G, rifampicin and sodium azide to the liquid repair medium showed that the repair required energy and lipid synthesis, and was not dependent on protein, peptidoglican or RNA synthesis. CONCLUSIONS Cell survival after PEF is dependent on the repair of the cytoplasmic membrane. Requirement of lipid synthesis for the repair of sublethally injured cells confirms that the cytoplasmic membrane is a target directly involved in the mechanism of inactivation by PEF. SIGNIFICANCE AND IMPACT OF THE STUDY Knowledge about the damages inflicted by PEF might help in the design of more efficient treatments.
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Affiliation(s)
- D García
- Departamento de Producción Animal y Ciencia de los Alimentos, Facultad de Veterinaria, Universidad de Zaragoza, Zaragoza, Spain
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Pagán R, Mañas P. Fundamental Aspects of Microbial Membrane Electroporation. PULSED ELECTRIC FIELDS TECHNOLOGY FOR THE FOOD INDUSTRY 2006. [DOI: 10.1007/978-0-387-31122-7_3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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ZHONG KUI, CHEN FANG, WU JIHONG, WANG ZHENGFU, LIAO XIAOJUN, HU XIAOSONG, ZHANG ZHENHUA. KINETICS OF INACTIVATION OF ESCHERICHIA COLI IN CARROT JUICE BY PULSED ELECTRIC FIELD. J FOOD PROCESS ENG 2005. [DOI: 10.1111/j.1745-4530.2005.00041.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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García D, Gómez N, Mañas P, Condón S, Raso J, Pagán R. Occurrence of sublethal injury after pulsed electric fields depending on the micro-organism, the treatment medium ph and the intensity of the treatment investigated. J Appl Microbiol 2005; 99:94-104. [PMID: 15960669 DOI: 10.1111/j.1365-2672.2005.02611.x] [Citation(s) in RCA: 101] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
AIMS The objective was to investigate the occurrence of sublethal injury after pulsed electric field (PEF) depending on the treatment time, the electric field strength and the pH of the treatment media in two Gram-positive (Bacillus subtilis ssp. niger, Listeria monocytogenes) and six Gram-negative (Escherichia coli, Escherichia coli O157:H7, Pseudomonas aeruginosa, Salmonella serotype Senftenberg 775W, Salmonella serotype Typhimurium, Yersinia enterocolitica) bacterial strains. METHODS AND RESULTS A characteristic behaviour was observed for the Gram-positive and Gram-negative bacteria studied. Whereas Gram-positive bacteria showed a higher PEF resistance at pH 7.0, the Gram-negative were more resistant at pH 4.0. In these conditions, in which bacteria showed their maximum resistance, a large proportion of sublethally injured cells were detected. In most cases, the longer the treatment time and the higher the electric field applied, the greater the proportion of sublethally injured cells that were detected. No sublethal injury was detected when Gram-positive bacteria were treated at pH 4.0 and Gram-negative at pH 7.0. CONCLUSIONS Sublethal injury was detected after PEF so, bacterial inactivation by PEF is not an 'all or nothing' event. SIGNIFICANCE AND IMPACT OF THE STUDY This work could be useful for improving food preservation by PEF.
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Affiliation(s)
- D García
- Departamento de Producción Animal y Ciencia de los Alimentos, Facultad de Veterinaria, Universidad de Zaragoza, Zaragoza, Spain
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Zhong K, Chen F, Wang Z, Wu J, Liao X, Hu X. Inactivation and kinetic model for the Escherichia coli treated by a co-axial pulsed electric field. Eur Food Res Technol 2005. [DOI: 10.1007/s00217-005-0015-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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30
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GARCIA DIEGO, HASSANI MOUNIR, MANAS PILAR, CONDON SANTIAGO, PAGAN RAFAEL. INACTIVATION OF ESCHERICHIA COLI O157:H7 DURING THE STORAGE UNDER REFRIGERATION OF APPLE JUICE TREATED BY PULSED ELECTRIC FIELDS. J Food Saf 2005. [DOI: 10.1111/j.0149-6085.2005.25552.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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