The Experts below are selected from a list of 10545 Experts worldwide ranked by ideXlab platform
Alexander Golberg - One of the best experts on this subject based on the ideXlab platform.
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differential cell death and regrowth of dermal fibroblasts and keratinocytes after application of Pulsed Electric Fields
Bioelectricity, 2020Co-Authors: Bodhisatwa Das, Alexander Golberg, Anil B Shrirao, Francois Berthiaume, Rene S Schloss, Martin L YarmushAbstract:Background: High-powered Pulsed Electric Fields (PEF) may be used for tissue debridement and disinfection, while lower PEF intensities may stimulate beneficial cellular responses for wound healing....
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IGBT-Based Pulsed Electric Fields Generator for Disinfection: Design and In Vitro Studies on Pseudomonas aeruginosa
Annals of Biomedical Engineering, 2019Co-Authors: Andrey Ethan Rubin, Klimenty Levkov, Osman Berk Usta, Martin Yarmush, Alexander GolbergAbstract:Irreversible electroporation of cell membrane with Pulsed Electric Fields is an emerging physical method for disinfection that aims to reduce the doses and volumes of used antibiotics for wound healing. Here we report on the design of the IGBT-based Pulsed Electric field generator that enabled eradication of multidrug resistant Pseudomonas aeruginosa PAO1 on the gel. Using a concentric Electric configuration we determined that the lower threshold of the Electric field required to kill P. aeruginosa PAO1 was 89.28 ± 12.89 V mm−1, when 200 square pulses of 300 µs duration are delivered at 3 Hz. These parameters disinfected 38.14 ± 0.79 mm2 area around the single needle electrode. This study provides a step towards the design of equipment required for multidrug-resistant bacteria disinfection in patients with Pulsed Electric Fields.
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rejuvenation of aged rat skin with Pulsed Electric Fields
Journal of Tissue Engineering and Regenerative Medicine, 2018Co-Authors: Nima Saeidi, Alexander Golberg, Kyle P. Quinn, Hassan Albadawi, Martin L Yarmush, Martin Villiger, Jake D Jones, William G AustinAbstract:The demand for skin rejuvenation procedures has progressively increased in the past decade. Additionally, clinical trials have shown that current therapies might cause downtime and side effects in patients including prolonged erythema, scarring, and dyspigmentation. The goal of this study was to explore the effect of partial irreversible electroporation (pIRE) with Pulsed Electric Fields in aged skin rejuvenation as a novel, non-invasive skin resurfacing technique. In this study, we used an experimental model of aged rats. We showed that treatment with pIRE promoted keratinocyte proliferation and blood flow in aged rat skin. We also found significant evidence indicating that pIRE reformed the dermal extracellular matrix (ECM). Both the collagen protein and fibre density in aged skin increased after pIRE administration. Furthermore, using an image-processing algorithm, we found that the collagen fibre orientation in the histological sections did not change, indicating a lack of scar formation in the treated areas. The results showed that pIRE approach could effectively stimulate keratinocyte proliferation, ECM synthesis, and angiogenesis in an aged rat model.
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Energy-efficient biomass processing with Pulsed Electric Fields for bioeconomy and sustainable development
Biotechnology for Biofuels, 2016Co-Authors: Alexander Golberg, Uwe Pliquett, Töpfl Stefan, Gintautas Saulis, Martin Sack, Gianpiero Pataro, Eugene Vorobiev, Justin Teissié, Damijan Miklavčič, Wolfgang FreyAbstract:Fossil resources-free sustainable development can be achieved through a transition to bioeconomy, an economy based on sustainable biomass-derived food, feed, chemicals, materials, and fuels. However, the transition to bioeconomy requires development of new energy-efficient technologies and processes to manipulate biomass feed stocks and their conversion into useful products, a collective term for which is biorefinery. One of the technological platforms that will enable various pathways of biomass conversion is based on Pulsed Electric Fields applications (PEF). Energy efficiency of PEF treatment is achieved by specific increase of cell membrane permeability, a phenomenon known as membrane electroporation. Here, we review the opportunities that PEF and electroporation provide for the development of sustainable biorefineries. We describe the use of PEF treatment in biomass engineering, drying, deconstruction, extraction of phytochemicals, improvement of fermentations, and biogas production. These applications show the potential of PEF and consequent membrane electroporation to enable the bioeconomy and sustainable development.
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eradication of multidrug resistant pseudomonas biofilm with Pulsed Electric Fields
Biotechnology and Bioengineering, 2016Co-Authors: Saiqa Khan, Alexander Golberg, Martin L Yarmush, Daniela Vecchio, Michael R Hamblin, Gaddi Blumrosen, Michael C MccormackAbstract:Biofilm formation is a significant problem, accounting for over eighty percent of microbial infections in the body. Biofilm eradication is problematic due to increased resistance to antibiotics and antimicrobials as compared to planktonic cells. The purpose of this study was to investigate the effect of Pulsed Electric Fields (PEF) on biofilm-infected mesh. Prolene mesh was infected with bioluminescent Pseudomonas aeruginosa and treated with PEF using a concentric electrode system to derive, in a single experiment, the critical Electric field strength needed to kill bacteria. The effect of the Electric field strength and the number of pulses (with a fixed pulse length duration and frequency) on bacterial eradication was investigated. For all experiments, biofilm formation and disruption were confirmed with bioluminescent imaging and Scanning Electron Microscopy (SEM). Computation and statistical methods were used to analyze treatment efficiency and to compare it to existing theoretical models. In all experiments 1500 V are applied through a central electrode, with pulse duration of 50 μs, and pulse delivery frequency of 2 Hz. We found that the critical Electric field strength (Ecr) needed to eradicate 100-80% of bacteria in the treated area was 121 ± 14 V/mm when 300 pulses were applied, and 235 ± 6.1 V/mm when 150 pulses were applied. The area at which 100-80% of bacteria were eradicated was 50.5 ± 9.9 mm(2) for 300 pulses, and 13.4 ± 0.65 mm(2) for 150 pulses. 80% threshold eradication was not achieved with 100 pulses. The results indicate that increased efficacy of treatment is due to increased number of pulses delivered. In addition, we that showed the bacterial death rate as a function of the Electrical field follows the statistical Weibull model for 150 and 300 pulses. We hypothesize that in the clinical setting, combining systemic antibacterial therapy with PEF will yield a synergistic effect leading to improved eradication of mesh infections.
Eugene Vorobiev - One of the best experts on this subject based on the ideXlab platform.
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Pulsed Electric Fields Pretreatments for the Cooking of Foods
Food Engineering Reviews, 2017Co-Authors: Jiří Blahovec, Eugene Vorobiev, Nikolai LebovkaAbstract:Development of the concept of electroporation opened new perspectives for promising applications in food technology. Treatment of foods with Pulsed Electric Fields (PEFs) allows facilitation of different food transformation operations (extraction, expression, osmotic treatment, drying, and freezing) with minimal energy consumptions and better retention of flavor, color, and preservation of nutritional properties of foods. This work shortly reviews the effects of PEF on the biological cells and food products and gives the examples of PEF-assisted techniques. The PEF protocol, power consumption, and existing small- and large-scale electroporation systems are presented. Some examples of PEF-assisted processing of meat, fish, and fat frying are discussed. The main principles of PEF-assisted cooking and kitchen operations are also discussed. The variants of PEF-assisted non-thermal cooker and PEF/ohmic thermal cooker are presented. It is speculated that PEF allows more homogeneous treatment of foods as compared to the conventional methods of thermal cooking. The PEF-assisted cooking can be faster and more effective for nutrient retention and sensory qualities of foods. Moreover, the PEF treatment can be used for producing the types of the products of fresh/natural quality and new tastes. The recent examples of PEF-assisted processing of meat and fish, assistance of frying, and commercial-scale processing are also presented and discussed.
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Energy-efficient biomass processing with Pulsed Electric Fields for bioeconomy and sustainable development
Biotechnology for Biofuels, 2016Co-Authors: Alexander Golberg, Uwe Pliquett, Töpfl Stefan, Gintautas Saulis, Martin Sack, Gianpiero Pataro, Eugene Vorobiev, Justin Teissié, Damijan Miklavčič, Wolfgang FreyAbstract:Fossil resources-free sustainable development can be achieved through a transition to bioeconomy, an economy based on sustainable biomass-derived food, feed, chemicals, materials, and fuels. However, the transition to bioeconomy requires development of new energy-efficient technologies and processes to manipulate biomass feed stocks and their conversion into useful products, a collective term for which is biorefinery. One of the technological platforms that will enable various pathways of biomass conversion is based on Pulsed Electric Fields applications (PEF). Energy efficiency of PEF treatment is achieved by specific increase of cell membrane permeability, a phenomenon known as membrane electroporation. Here, we review the opportunities that PEF and electroporation provide for the development of sustainable biorefineries. We describe the use of PEF treatment in biomass engineering, drying, deconstruction, extraction of phytochemicals, improvement of fermentations, and biogas production. These applications show the potential of PEF and consequent membrane electroporation to enable the bioeconomy and sustainable development.
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valorization of oilseed residues extraction of polyphenols from flaxseed hulls by Pulsed Electric Fields
Industrial Crops and Products, 2014Co-Authors: Nadia Boussetta, Jeanlouis Lanoiselle, E Soichi, Eugene VorobievAbstract:Abstract This work aims at obtaining extracts with high level of polyphenols from flaxseed hulls treated by Pulsed Electric Fields (PEF). The effect of the different operating parameters was studied on the extraction of polyphenols such as the PEF treatment duration, the PEF Electric field strength, the solvent composition (ethanol, acid or base content) and the rehydration duration of the product. Results have shown that a PEF treatment allowed the extraction of up to 80% of polyphenols when applied at 20 kV/cm for 10 ms. For lower PEF Electric field strength, the extraction efficiency was smaller. The rehydration of the product before PEF application improved the treatment efficiency. The highest polyphenols increase (≈37%) was observed when the product was rehydrated for 40 min before PEF application. The addition of ethanol, citric acid and sodium hydroxide has increased the extraction of polyphenols. The highest polyphenols yield was reached with a solvent containing 20% of ethanol and 0.3 mol/L hydroxide sodium. The alkaline hydrolysis was more effective than the acidic hydrolysis.
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Pilot scale inulin extraction from chicory roots assisted by Pulsed Electric Fields
International Journal of Food Science and Technology, 2012Co-Authors: Zhenzhou Zhu, Olivier Bals, Nabil Grimi, Eugene VorobievAbstract:Summary A pilot study for the Pulsed Electric Fields (PEF) assisted countercurrent diffusion of inulin from chicory roots is presented. The influence of PEF parameters (Electric field intensity E = 600 V cm−1, treatment duration tPEF = 10–50 ms) and diffusion temperature (varied between 30 and 80 °C) on soluble matter extraction kinetics, inulin content of juice, and pulp exhaustion are investigated. The draft (liquid to solid mass ratio) was fixed at 140%, similar to the industrial conditions. PEF treatment facilitates extraction of inulin at conventional diffusion temperature (70–80 °C), and diffusion temperature can even be reduced by 10–15 °C with comparable juice inulin concentration. Less energy consumption can be achieved by reducing PEF treatment duration to 10 ms, which is observed sufficient for effective extraction.
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freezing of potato tissue pre treated by Pulsed Electric Fields
Lwt - Food Science and Technology, 2009Co-Authors: Mounia Jalte, Nikolai Lebovka, Jeanlouis Lanoiselle, Eugene VorobievAbstract:Abstract The effects of Pulsed Electric Fields (PEF) pre-treatment on the freezing, freeze-drying and rehydration behavior of potato were studied. Potato samples (26 mm diameter, 10 mm high) were treated by PEF (400 V/cm) for various durations between 10 −4 and 0.3 s. The degree of tissue damage was quantified by the change in Electrical conductivity. PEF treated and untreated samples were either frozen in an air-blast freezer with air at −35 °C and 2 m/s velocity or freeze-dried at 0 °C and 0.04 mbar pressure and then rehydrated in water at 25 °C. The freezing times for PEF pre-treated samples reduced as the PEF-induced tissue damage increased. Scanning electron microscope images of the air-blast frozen and then freeze-dried samples showed increased deformation of cells and larger intercellular spaces (frozen samples only) for the PEF pre-treated samples. However, PEF pre-treatment improved the rate of freeze-drying and improved the quality and rehydration of the samples.
Nikolai Lebovka - One of the best experts on this subject based on the ideXlab platform.
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Pulsed Electric Fields Pretreatments for the Cooking of Foods
Food Engineering Reviews, 2017Co-Authors: Jiří Blahovec, Eugene Vorobiev, Nikolai LebovkaAbstract:Development of the concept of electroporation opened new perspectives for promising applications in food technology. Treatment of foods with Pulsed Electric Fields (PEFs) allows facilitation of different food transformation operations (extraction, expression, osmotic treatment, drying, and freezing) with minimal energy consumptions and better retention of flavor, color, and preservation of nutritional properties of foods. This work shortly reviews the effects of PEF on the biological cells and food products and gives the examples of PEF-assisted techniques. The PEF protocol, power consumption, and existing small- and large-scale electroporation systems are presented. Some examples of PEF-assisted processing of meat, fish, and fat frying are discussed. The main principles of PEF-assisted cooking and kitchen operations are also discussed. The variants of PEF-assisted non-thermal cooker and PEF/ohmic thermal cooker are presented. It is speculated that PEF allows more homogeneous treatment of foods as compared to the conventional methods of thermal cooking. The PEF-assisted cooking can be faster and more effective for nutrient retention and sensory qualities of foods. Moreover, the PEF treatment can be used for producing the types of the products of fresh/natural quality and new tastes. The recent examples of PEF-assisted processing of meat and fish, assistance of frying, and commercial-scale processing are also presented and discussed.
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Pulsed Electric Fields-assisted extraction from exotic fruit residues
Handbook of Electroporation, 2017Co-Authors: Francisco J Barba, Oleksii Parniakov, Mohamed Koubaa, Nikolai LebovkaAbstract:The production of exotic fruits (i.e., mango, papaya) is in continuous increase in the world. It reflects not only their appreciation by consumers and their decreasing prices, but it is also due to their increasing demand in food industry for the preparation of juices and beverages. Consequently, considerable amount of waste and by-products are generated during the processing of these fruits, which aregenerally modestly valorized as animal feed. Nevertheless, these residues represent a great source of valuable compounds that could be recovered and used for many purposes as food additives and/or nutraceuticals. The most common methods used for the recovery of these compounds are maceration and thermal extraction. These conventional methods, although efficient, are time and energy consuming, use generally toxic and expensive solvents, and may lead to the degradation and loss of thermosensitive molecules. In order to overcome these issues, numerous nonconventional technologies (i.e., Pulsed Electric Fields) have been evaluated and introduced in many industries. These methods may allow recovering the target compounds selectively and in "green" manner. Reducing the energy consumption, the processing time, and downstream processing steps, along with the nonuse of toxic solvents and the preservation of the most thermolabile compounds, are the major advantages of these technologies. In this chapter, an overview of mango and papaya fruits' production, composition, and generated waste is provided. An emphasis is then given on the use of electro-technologies, especially Pulsed Electric Fields (PEF) and high voltage Electrical discharges (HVED), to recover high added value compounds from their fruit peels and seeds.
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freezing of potato tissue pre treated by Pulsed Electric Fields
Lwt - Food Science and Technology, 2009Co-Authors: Mounia Jalte, Nikolai Lebovka, Jeanlouis Lanoiselle, Eugene VorobievAbstract:Abstract The effects of Pulsed Electric Fields (PEF) pre-treatment on the freezing, freeze-drying and rehydration behavior of potato were studied. Potato samples (26 mm diameter, 10 mm high) were treated by PEF (400 V/cm) for various durations between 10 −4 and 0.3 s. The degree of tissue damage was quantified by the change in Electrical conductivity. PEF treated and untreated samples were either frozen in an air-blast freezer with air at −35 °C and 2 m/s velocity or freeze-dried at 0 °C and 0.04 mbar pressure and then rehydrated in water at 25 °C. The freezing times for PEF pre-treated samples reduced as the PEF-induced tissue damage increased. Scanning electron microscope images of the air-blast frozen and then freeze-dried samples showed increased deformation of cells and larger intercellular spaces (frozen samples only) for the PEF pre-treated samples. However, PEF pre-treatment improved the rate of freeze-drying and improved the quality and rehydration of the samples.
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Pulse Duration and Efficiency of Soft Cellular Tissue Disintegration by Pulsed Electric Fields
Food and Bioprocess Technology, 2008Co-Authors: Francesca Vito, Nikolai Lebovka, Giovanna Ferrari, Nikolai Shynkaryk, Eugene VorobievAbstract:The effect of pulse duration on efficiency of disintegration of apple tissue by Pulsed Electric Fields (PEF) was studied. The samples (26-mm diameter, 10-mm height) were treated by PEF at Electric field strength E between 100 and 400 V/cm, pulse duration t _i of 10, 100, 1,000 μs, inter-pulse duration Δ t of 100 μs and different number of pulses n . Both the degree and the time evolution of tissue damage were quantified by Electrical conductivity disintegration index Z and characteristic damage time τ , respectively. The samples exposed to the same PEF treatment time nt _i showed noticeably higher disintegration efficiency for larger pulse duration. The synergism of PEF and thermal treatment with temperature T (20–50 °C) was demonstrated. The Arrhenius dependence of τ ( T ) for PEF treatment at E = 100 V/cm gave the decreasing activation energy W as a function of t _i, ( Q ≈ 164 kJ/mol at t _i = 10 μs, Q ≈ 109 kJ/mol at t _i = 100 μs and Q ≈ 66 kJ/mol at t _i = 1,000 μs). Textural relaxation data supported the higher damage efficiency for longer pulse duration.
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estimation of characteristic damage time of food materials in Pulsed Electric Fields
Journal of Food Engineering, 2002Co-Authors: Nikolai Lebovka, Maksym Bazhal, Eugene VorobievAbstract:Abstract A method based on the Electrical conductivity measurements is proposed to estimate the characteristic damage time ( τ ) of a food material in Pulsed-Electric Fields (PEF). Empirical dependencies of τ versus Electric field intensity E are obtained for apple, carrot and potato tissues. The generalized electroporation theory accounting for the sphericity of biological cells and distribution of their geometric sizes gives a credible description of the experimentally observed dependencies τ ( E ). An optimal Electric field intensity E opt that corresponds to minimum of power consumption at maximum of material disintegration is estimated theoretically and experimentally. For investigated tissue materials, the experimentally estimated value of E opt is approximately 400 V cm −1 . The energy consumption during the PEF treatment at E opt ≈400 V cm −1 decreases in the next order: apple → carrot → potato.
Martin L Yarmush - One of the best experts on this subject based on the ideXlab platform.
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differential cell death and regrowth of dermal fibroblasts and keratinocytes after application of Pulsed Electric Fields
Bioelectricity, 2020Co-Authors: Bodhisatwa Das, Alexander Golberg, Anil B Shrirao, Francois Berthiaume, Rene S Schloss, Martin L YarmushAbstract:Background: High-powered Pulsed Electric Fields (PEF) may be used for tissue debridement and disinfection, while lower PEF intensities may stimulate beneficial cellular responses for wound healing....
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rejuvenation of aged rat skin with Pulsed Electric Fields
Journal of Tissue Engineering and Regenerative Medicine, 2018Co-Authors: Nima Saeidi, Alexander Golberg, Kyle P. Quinn, Hassan Albadawi, Martin L Yarmush, Martin Villiger, Jake D Jones, William G AustinAbstract:The demand for skin rejuvenation procedures has progressively increased in the past decade. Additionally, clinical trials have shown that current therapies might cause downtime and side effects in patients including prolonged erythema, scarring, and dyspigmentation. The goal of this study was to explore the effect of partial irreversible electroporation (pIRE) with Pulsed Electric Fields in aged skin rejuvenation as a novel, non-invasive skin resurfacing technique. In this study, we used an experimental model of aged rats. We showed that treatment with pIRE promoted keratinocyte proliferation and blood flow in aged rat skin. We also found significant evidence indicating that pIRE reformed the dermal extracellular matrix (ECM). Both the collagen protein and fibre density in aged skin increased after pIRE administration. Furthermore, using an image-processing algorithm, we found that the collagen fibre orientation in the histological sections did not change, indicating a lack of scar formation in the treated areas. The results showed that pIRE approach could effectively stimulate keratinocyte proliferation, ECM synthesis, and angiogenesis in an aged rat model.
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eradication of multidrug resistant pseudomonas biofilm with Pulsed Electric Fields
Biotechnology and Bioengineering, 2016Co-Authors: Saiqa Khan, Alexander Golberg, Martin L Yarmush, Daniela Vecchio, Michael R Hamblin, Gaddi Blumrosen, Michael C MccormackAbstract:Biofilm formation is a significant problem, accounting for over eighty percent of microbial infections in the body. Biofilm eradication is problematic due to increased resistance to antibiotics and antimicrobials as compared to planktonic cells. The purpose of this study was to investigate the effect of Pulsed Electric Fields (PEF) on biofilm-infected mesh. Prolene mesh was infected with bioluminescent Pseudomonas aeruginosa and treated with PEF using a concentric electrode system to derive, in a single experiment, the critical Electric field strength needed to kill bacteria. The effect of the Electric field strength and the number of pulses (with a fixed pulse length duration and frequency) on bacterial eradication was investigated. For all experiments, biofilm formation and disruption were confirmed with bioluminescent imaging and Scanning Electron Microscopy (SEM). Computation and statistical methods were used to analyze treatment efficiency and to compare it to existing theoretical models. In all experiments 1500 V are applied through a central electrode, with pulse duration of 50 μs, and pulse delivery frequency of 2 Hz. We found that the critical Electric field strength (Ecr) needed to eradicate 100-80% of bacteria in the treated area was 121 ± 14 V/mm when 300 pulses were applied, and 235 ± 6.1 V/mm when 150 pulses were applied. The area at which 100-80% of bacteria were eradicated was 50.5 ± 9.9 mm(2) for 300 pulses, and 13.4 ± 0.65 mm(2) for 150 pulses. 80% threshold eradication was not achieved with 100 pulses. The results indicate that increased efficacy of treatment is due to increased number of pulses delivered. In addition, we that showed the bacterial death rate as a function of the Electrical field follows the statistical Weibull model for 150 and 300 pulses. We hypothesize that in the clinical setting, combining systemic antibacterial therapy with PEF will yield a synergistic effect leading to improved eradication of mesh infections.
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Pulsed Electric Fields for burn wound disinfection in a murine model
Journal of Burn Care & Research, 2015Co-Authors: Alexander Golberg, Saiqa Khan, Martin L Yarmush, Felix G Broelsch, Daniela Vecchio, Michael R Hamblin, W G Austen, Robert L SheridanAbstract:Emerging bacterial resistance renders many antibiotics ineffective, making alternative strategies of wound disinfection important. Here the authors report on a new, physical burn wound disinfection method: Pulsed Electric Fields (PEFs). High voltage, short PEFs create nonthermal, permanent damage to cell membranes, possibly by irreversible electroporation. In medicine, PEF technology has recently been used for nonthermal ablation of solid tumors. The authors have expanded the spectrum of PEF applications in medicine to burn wound disinfection. A third-degree burn was induced on the dorsal skin of C57BL/6 mice. Immediately after the injury, the burn wound was infected with Acinetobacter baumannii expressing the luxCDABE operon. Thirty minutes after infection, the infected areas were treated with 80 pulses delivered at 500 V/mm, 70 μs, 1 Hz. The authors used bioluminescence to quantify bacteria on skin. Three animals were used for each experimental condition. PEFs were effective in the disinfection of infected burned murine skin. The bacterial load reduction correlated with the number of delivered pulses. Forty pulses of 500 V/mm led to a 2.04 ± 0.29 Log10 reduction in bacterial load; 80 pulses led to the immediate 5.53 ± 0.30 Log10 reduction. Three hours after PEF, the bacterial reduction of the skin treated with 500 V/mm, 80 pulses was 4.91 ± 0.71 Log10. The authors introduce a new method of wound disinfection using high voltage, short PEFs. They believe that PEF technology may represent an important alternative to antibiotics in addressing bacterial contamination of wounds, particularly those contaminated with multidrug-resistant bacteria.
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regeneration and control of human fibroblast cell density by intermittently delivered Pulsed Electric Fields
Biotechnology and Bioengineering, 2013Co-Authors: Alexander Golberg, Martin L Yarmush, Robert L Sheridan, Marianna BeiAbstract:Proliferative scarring is a human disease with neither available effective treatment nor relevant animal model. One of the hypotheses for scar formation involves deregulation of fibroblast signaling and delayed apoptosis. Here, we introduce a new chemical-free method for fibro- blast density control in culture by intermittently delivered Pulsed Electric Fields (IDPEF), which cause irreversible damage to cell membranes. Using 5-100 pulses with Electric field strength of 150 V/mm, pulse duration 70 ms, and frequency of 1 Hz, we investigated the effects of PEF appli- cation on growth, death, and regeneration of normal human dermal fibroblasts in culture. We found that the fraction of fibroblasts that survive depends on the number of pulses applied and follows a Weibull distribution. We have suc- cessfully developed an IDPEF protocol that controls fibro- blasts density in culture. Specifically, through application of IDPEF every 72 h for 12 days, we maintain a normal human dermal fibroblast density in the 3.1 � 0.2 � 10 5 - 1.4 � 0.2 � 10 5 cell/mL range. Our results suggest that IDPEFs may prove useful as a non-chemical method for fibroblast density control in human wound healing. Biotechnol. Bioeng. 2013;110: 1759-1768.
Olga Martinbelloso - One of the best experts on this subject based on the ideXlab platform.
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Pulsed Electric Fields processing effects on quality and health related constituents of plant based foods
Trends in Food Science and Technology, 2013Co-Authors: Isabel Odriozolaserrano, Robe Solivafortuny, Ingrid Aguiloaguayo, Olga MartinbellosoAbstract:Although representing an excellent way of decontaminating foods, thermal processes have been shown to cause some deleterious effects on quality-related compounds. In turn, in plant-based foods some of these compounds also exhibit health-promoting biological functions. Non-thermal processing technologies, such as Pulsed Electric Fields (PEF) have been developed during the last decades as an alternative to thermal pasteurization of liquid foods. This review summarizes the main results achieved within the framework of the EU FP6 integrated project ‘NovelQ’ regarding the effects of PEF on the main compounds affecting quality- and health-related properties. The reported results show that PEF can be used to pasteurize fruit juices with a significantly higher amount of aroma compounds and health-related phytochemicals. However, the residual amounts of certain enzymes in the treated juices appear to greatly affect the stability of these compounds along storage.
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changes in the polyphenol profile of tomato juices processed by Pulsed Electric Fields
Journal of Agricultural and Food Chemistry, 2012Co-Authors: Anna Vallverduqueralt, Pedro Elezmartinez, Isabel Odriozolaserrano, Gemma Omsoliu, Rosa M Lamuelaraventos, Olga MartinbellosoAbstract:The effect of Pulsed Electric Fields on the polyphenol profile of tomato juices was studied. First, tomatoes were subjected to moderate-intensity Pulsed Electric Fields (MIPEFs) and then were immediately refrigerated at 4 °C for 24 h. Treated and untreated juices were then subjected to high-intensity Pulsed Electric Fields (HIPEFs) or thermal treatment (90 °C for 60 s). In comparison to references, tomatoes subjected to MIPEF treatments led to juices with a higher content of polyphenol compounds. A slight decrease in polyphenol compounds was observed over time in thermal- and HIPEF-treated juices, with the exception of caffeic acid. However, HIPEF-processed tomato juices had a higher content of polyphenol compounds (ferulic acid, caffeic-O-glucoside acid, p-coumaric acid, chlorogenic acid, rutin, and naringenin) just after processing and through storage than those thermally treated. Therefore, the combination of MIPEFs and HIPEFs could be proposed as a strategy for producing tomato juices with a higher co...
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effects of Pulsed Electric Fields on bioactive compounds in foods a review
Trends in Food Science and Technology, 2009Co-Authors: Robe Solivafortuny, Ana Alasa, Dietrich Kno, Olga MartinbellosoAbstract:Pulsed Electric Fields have the potential to be used as alternative to other conventional techniques of food production. In the last few years, several studies have demonstrated the ability of intense treatments to obtain safe and shelf-stable liquid foods. On the other hand, novel applications such as improvement of mass transfer processes or generation of bioactive compounds by using moderate field strengths are under current development. However, the effects of Pulsed Electric field treatments on minor constituents of foods, namely on bioactive compounds, have not been always considered. This review aims at updating the state of the art regarding the impact of Pulsed Electric field processing conditions on the stability of bioactive compounds in food systems.
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non thermal pasteurization of fruit juices by combining high intensity Pulsed Electric Fields with natural antimicrobials
Innovative Food Science and Emerging Technologies, 2008Co-Authors: Jonathan Mosquedamelgar, Rosa M Raybaudimassilia, Olga MartinbellosoAbstract:Abstract The effect of high-intensity Pulsed Electric Fields (HIPEF) on the Salmonella Enteritidis and Escherichia coli O157:H7 populations inoculated in apple, pear, orange and strawberry juices as influenced by treatment time and pulse frequency was investigated. Combinations of HIPEF (35 kV/cm, 4 μs pulse length in bipolar mode without exceeding 40 °C) with citric acid or cinnamon bark oil against these pathogenic microorganisms in fruit juices were also evaluated. Treatment time was the more influential factor on the microbial reduction in all the fruit juices analyzed. S. Enteritidis and E. coli O157:H7 were reduced by more than 5.0 log 10 units in orange juice treated by only HIPEF; whereas strawberry, apple and pear juices were pasteurized when HIPEF was combined with citric acid at 0.5, 1.5, 1.5%, respectively, or cinnamon bark oil at 0.05, 0.1 and 0.1%, respectively. Synergistic and additive killing effects against S. Enteritidis and E. coli O157:H7 in fruit juices by combining treatments were observed. Industrial relevance The use of high-intensity Pulsed Electric Fields treatment as a non-thermal pasteurization method in combination with organic acids or essential oils is an effective process for eliminating S. Enteritidis and E. coli O157:H7 populations in fruit juices upper 5.0 log 10 reductions. Therefore, combinations of those treatments may help to ensure the microbiological safety in juice products, and to reduce the risk of food-borne illness caused by the consumption of these kinds of foods.
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inactivation of lactobacillus brevis in orange juice by high intensity Pulsed Electric Fields
Food Microbiology, 2005Co-Authors: Pedro Elezmartinez, Robe Solivafortuny, Joan Escolahernandez, Olga MartinbellosoAbstract:High-intensity Pulsed Electric Fields (HIPEF) is a non-thermal preservation method which is believed to be able to inactivate spoilage micro-organisms such as Lactobacillus brevis. The effects of HIPEF parameters (Electric field strength, treatment time, pulse polarity, frequency and pulse width) and heat pasteurization (90 degreesC/1 min) were evaluated on samples of orange juice inoculated with L. brevis (10(8) cfu/ml). HIPEF as well as heat treatments were carried out in continuous flow equipments. Electron microscopy was performed in order to observe L. brevis cell damage induced by HIPEF treatment. HIPEF processing of orange juice was more effective in inactivating L. brevis than thermal processing. The extent of microbial inactivation depended on the processing parameters (p < 0.01). L. brevis destruction was greater when the Electric field strength and the treatment time increased, and also when the pulse frequency and the pulse width decreased. L. brevis was inactivated to a maximum of 5.8 log reductions when inoculated orange juice was processed at 35 kV/cm for 1000 mus using 4 mus pulse width in bipolar mode and 200 Hz at less than 32degreesC. Mechanical breakdown of cell walls was observed in L. brevis when orange juice was processed by HIPEF
