Effects Of High-voltage Electrostatic Field Research Articles

Investigating the Effect of High-Voltage Electrostatic Field (HVEF) Treatment on the Physicochemical Characteristics, Bioactive Substances Content, and Shelf Life of Tomatoes.

This study evaluated the ability of a high-voltage electrostatic field (HVEF) treatment to extend the shelf life of tomatoes. Tomatoes were exposed to HVEF treatment for different lengths of time, and the physicochemical properties of tomatoes and bioactive compounds were monitored during 28 days of storage at 4 °C. The results indicated that the quality parameters of tomatoes were better maintained during storage by the HVEF treatment relative to the control treatment, extending their shelf life by 14-28 days. The HVEF treatment mitigated losses in firmness, weight, color changes, and bioactive substances, such as total phenolic content, total flavonoid content, ascorbic acid, and lycopene. The activity of pectin-degrading enzymes was also inhibited. The best exposure times for the HVEF treatment were 90 and 120 min. While the measured parameters decreased in both the control and HVEF treatment groups, the decrease in all of these measured parameters was significantly less (p < 0.05) in the optimum HVEF treatment groups than in the control. While the physicochemical properties may vary between different tomato varieties, the HVEF treatment of harvested tomatoes for 90 or 120 min can mitigate the degradation of quality parameters and loss of bioactive compounds incurred during the postharvest storage of tomatoes, thus maintaining their commercial value.

Effect of high-voltage electrostatic field treatments on bananas (Musa paradisiaca var. sapientum) on their postharvest quality, enzymatic activity and morphological changes

In this work, the effects of high-voltage electrostatic field (HVEF) on enzyme activities and appearance of stored Musa sapientum were investigated as well as the intensity of spotting by Digital Image Analysis (DIA). By applying HVEF at 6 kV cm−1 during 7.5 minutes, color features on their surface after day 4, maintained stable values (R ≥ 191, G ≥ 165, L* ≥ 82, and b* ≥ 41), while control samples had lower figures of these parameters. Enzyme activities (expressed as Umg protein−1), for pectinmethylesterase in peel, HVEF treatments induced values ≤ 9 Umg−1, while control ≥ 16 Umg−1; polygalacturonase in peel; HVEF samples had activities ≤ 120 Umg−1 at days 6 and 8, while control samples ≥ 211 Umg−1; and, in pulp, after day 4, HVEF brought activities ≤ 37 Umg−1 while control samples were ≥ 71 Umg−1. Polyphenoloxidase, activities for treated samples were enhanced (in the peel, HVEF samples ≥553 Umg −1 and control ones ≤425 Umg−1; and for pulp, HVEF induced activities ≥979 Umg−1 while control ≤717 Umg −1). These results did not impact negatively in the spotting on the surface of the fruits. Results suggested that HVEF can extend the shelf life of M. sapientum.

The effect of high-voltage electrostatic field on the interactions between duck myofibrillar protein and inulin: An underlying mechanisms study

This study investigated the effect of high-voltage electrostatic field (HVEF) treatment on the interactions between duck myofibrillar protein (MP) and inulin, as well as explored the gel properties of adding inulin to duck MP. Hence, different inulin content (0–30 mg mL−1) were added to duck MP and HVEF treatment was applied in the gelation process.The results revealed that HVEF combined with the addition of 30 mg mL−1 inulin treatment significantly increased (P < 0.05) the water holding capacity and gel strength by 0.20 and 2.61 times, respectively. Moreover, the rheological characteristics and the formation of the three-dimensional network structure was promoted after added inulin and applied HVEF treatment. The HVEF treatment in modifying MP-inulin interaction promoted the conversion of α-helix to β-sheet, β-turn and random coil, significantly increased (P < 0.05) the content of R–SH groups and surface hydrophobicity, thus revealing the underlying mechanisms of the enhancement of duck MP gel performance. Principal component analysis revealed these interrelationships. This data demonstrated that inulin addition combined with HVEF treatment might be a new and effective strategy to enhance the duck MP gel properties.

Effects of high-voltage electrostatic field (HVEF) on frozen shrimp (Solenocera melantho) based on UPLC-MS untargeted metabolism

Shrimp meat is prone to autolysis and decay due to the abundance of endogenous enzymes and contamination from microorganisms. HVEF freezing can slow the spoilage of shrimp, producing small and uniform ice crystals, resulting in less damage to muscle tissue. In this study, HVEF technique was used to freeze the shrimp (Solenocera melantho), and the UPLC-MS metabolic technique was used to investigate the metabolites of frozen shrimp meat. Compared with the control group, 367 differential metabolites were identified in the HVEF group. Mapping them to the KEGG database, there were 108 with KEGG ID. Purine metabolism and pyrimidine metabolism were the most enriched pathways. In addition, phosphatidylcholines (PCs), inosine (HxR), and l-valine were identified as potential biomarkers associated with lipid, nucleotide, and organic acid metabolism, respectively. Overall, HVEF can improve freezing quality of shrimp meat by slowing down the metabolism of substances in the muscle of S. melantho.

The effects of freezing under a high-voltage electrostatic field on ice crystals formation, physicochemical indices, and bacterial communities of shrimp (Solenocera melantho)

A high-voltage electrostatic field (HVEF) can affect the formation of ice crystals and improve food quality by inhibiting the growth of some bacteria. In this study, different intensities of HVEF were used to assist in the shrimp ( Solenocera melantho ) freezing process, and the effects of the HVEF were explored using the ice crystal structure, physicochemical indexes, and bacterial communities. The results showed that the HVEF effectively improved the freezing quality of S. melantho . The freezing speed was improved, especially in the zone of maximum crystallization. Small and uniform ice crystals were generated at 15 kV/m and 20 kV/m. The texture of the shrimp muscle improved, and the degeneration of myofibrillar protein isolates decreased. Blackening of the shrimp head and polyphenol oxidase activity were inhibited. High-throughput sequencing analysis showed that the bacterial community structure changed significantly at 15 and 20 kV/m, which was lower than that in the other groups. The HVEF exerted an inhibitory effect on most bacteria, and this effect was related to the intensity of the HVEF. Based on these results and energy consumption considerations, the HVEF at 15 kV/m is more suitable for the auxiliary freezing of S. melantho . • High-voltage electrostatic field (HVEF) was used to treat the S. melantho. • The optimal electric field intensity of HVEF on freezing S. melantho was determined. • Ice crystal structure was investigated to study the change of freezing quality of S. melantho. • The effects of HVEF on the bacterial communities of S. melantho were studied by 16S rRNA.

Application of HVEF treatment in bacteriostasis against Acinetobacter radioresistens

This study aimed to investigate the antimicrobial effect of high-voltage electrostatic field (HVEF) on Acinetobacter radioresistens. The optimal bacterial reduction condition of HVEF for A. radioresistens was 30 kV/15 min. The membrane morphology was distorted and cellular contents were leaked in A. radioresistens after HVEF treatment. In comparison with those in the control group, the gene expressions of AhpC, KatE, and Nfo were increased by 1.87-, 3.08-, and 2.26-fold in A. radioresistens, while the gene expressions of RecG, RadA, RecN, and Dps were up-regulated by1.62-, 2.16-, 2.92- and 1.23-fold in A. radioresistens, respectively. The morphological and quantitative real-time PCR results revealed that HVEF treatment had strong antibacterial effect, and it inhibited gene transcription to disrupt cell membrane structure and energy transport. This study provides a theoretical basis for the development and utilization of HVEF treatment as an antimicrobial technology.

Effect of high-voltage electrostatic field on cryopreservation of human epidermal melanocytes

The objective of this research was to evaluate the influence of high-voltage electrostatic field (HVEF) on the freezing of human epidermal melanocytes (HEM) with respect to the degree of cell deformation, survival and proliferation rate after cell resuscitation. As a result, the degree of supercooling is increased by enhancing the strength of the static electric field in the range of 15 kV/m, and the maximum supercooling degree is 7.83±0.05 °C at 15 kV/m. By contrast, the morphology of the electric field assisted freezing cell after resuscitation was significantly improved, and the best electric field strength for cryopreservation is 15 kV/m. The survival rate of human epidermal melanocytes recovered was 88.03%, which was higher than that of the control group. The proliferation rate at 24, 48 and 72 hours are 17%, 28% and 25%, respectively, which are higher than that of the control cells. These findings demonstrate that the freezing HVEF can protect the cell physiological activity, and reduce the freezing damage. Therefore, the optimal HVEF cryopreservation technology be of great significance for the research of tissue engineering in repairing wounds, infections, and promote the development of food, medicine and other fields.

Effects of HVEF treatment on microbial communities and physicochemical properties of catfish fillets during chilled storage

The effects of high-voltage electrostatic field (HVEF) on the microbial communities and quality characteristics of catfish fillets were investigated. Samples with 30 kV/15 min HVEF treatment and without treatment (control) were stored at 4 °C for 0, 1, 3, 5 and 7 d. The total volatile basic nitrogen (TVB-N) and total viable count (TVC) of HVEF-treated sample (20.5 mg/100 g and 5.64 log CFU/g, respectively) were significantly lower than those of the control (32.4 mg/100 g and 7.42 log CFU/g, respectively) at 7 d. Therefore, the shelf life of HVEF-treated fillets was 2 days longer than the control (5 d). Besides, HVEF treated samples showed less tissue damages, lower thiobarbituric acid-reactive substances (TBARS) and higher water holding capacity throughout the chilling storage. Additionally, the high-throughput sequencing results indicated that HVEF treatment reduced the relevant abundance of Flavobacterium and Geobacillus at 0 d, and mainly inhibited the growth of Acinetobacter and Streptococcus after 7 d storage, which meant the growth of spoilage bacteria were inhibited, corresponding with the results of TVB-N and TVC. The results indicated HVEF treatment could be implemented as a new fish processing technology to delay product quality deterioration and extend the shelf life of catfish fillets.

The Sterilization Effect of Cooperative Treatment of High Voltage Electrostatic Field and Variable Frequency Pulsed Electromagnetic Field on Heterotrophic Bacteria in Circulating Cooling Water

Compared to other treatment of industrial circulating cooling water in the field of industrial water treatment, high-voltage electrostatic field and variable frequency pulsed electromagnetic field co-sterilization technology, an advanced technology, is widely used because of its special characteristics--low energy consumption, nonpoisonous and environmentally friendly. In order to get a better cooling water sterilization effect under the premise of not polluting the environment, some experiments about sterilization of heterotrophic bacteria in industrial circulating cooling water by cooperative treatment of high voltage electrostatic field and variable frequency pulsed electromagnetic field were carried out. The comparison experiment on the sterilization effect of high-voltage electrostatic field and variable frequency pulsed electromagnetic field co-sterilization on heterotrophic bacteria in industrial circulating cooling water was carried out by change electric field strength and pulse frequency. The results show that the bactericidal rate is selective to the frequency and output voltage, and the heterotrophic bacterium can only kill under the condition of sweep frequency range and output voltage. When the voltage of the high voltage power supply is 4000V, the pulse frequency is 1000Hz and the water temperature is 30°C, the sterilization rate is 48.7%, the sterilization rate is over 90%. Results of this study have important guiding significance for future application of magnetic field sterilization.

The Influence of High Voltage Electrostatic Field on Sea Water Evaporation and the Boiling Point

This paper studied the effects of high voltage electrostatic field on the seawater under the condition of constant temperature of 70oC and the initial temperatures of 70oC with no constantly heating, and in compared with the control group with no high voltage electrostatic field .Besides, this paper explored the effect of high-voltage electrostatic field on the water boiling point. The experimental results showed that water evaporation rate in the presence of high voltage electrostatic field was significantly faster than the control group, and the seawater evaporation rate under the condition of constant temperature of 70oC was 1.5 to 2.1 times faster than that of the control group; In initial temperature of 70oC, the average water evaporation rate is faster than the control group with no constant temperature heating, and experimental temperature-dropping rate was significantly faster than the control group, meanwhile the experimental group high pressure loop current was about 200uA.It was also found that as the high voltage electrostatic field strength increased the water boiling point was reduced gradually trend. The verification by the experimental results shows the mechanism that the water molecules which is polar molecules is so easy to form the electric dipole moment in high voltage electrostatic field that the hydrogen bonding between water molecules break easily, and the water vapor evaporates more quickly from the seawater. It also proved that the energy to break hydrogen bond was provided by the water inner system but not the transformation of the electric field.

Effects of high-voltage electrostatic field on the freezing behavior and quality of pork tenderloin

This study investigated the effects of a high-voltage electrostatic field (HVEF) on the freezing behavior and quality maintenance of pork tenderloin. Based on the freezing behavior of deionized water (DW) under both AC and DC conditions, the freezing of pork samples using DC treatment was examined. It was found that the freezing point (Tm) and phase-transition time (crystallization time, tc) of the meat varied with increasing voltage. The water-holding capacity of samples treated by 10 kV exceeded that of the control group, which was proven using low-field nuclear calorimetry (LF-NMR) and differential scanning calorimetry (DSC). The total area of ice crystal for the cross sections of pork tenderloin treated with 10 kV HVEF was much smaller than that without HVEF. Microstructural observations indicated that freezing assisted by 10 kV HVEF was superior to freezing without HVEF in maintaining the quality of frozen pork.

Effect of High-Voltage Electrostatic Field on Inorganic Nitrogen Uptake by Cucumber Plants

<abstract> We investigated the inorganic nitrogen uptake by cucumber ( L.) plants under high-voltage electrostatic field (HVEF). The maximum uptake rates and affinities significantly changed with increasing field intensity. Ammonium uptake slightly increased when the field intensity increased to 1.0 kV cm^-1 and then decreased between 2.0 and 3.0 kV cm^-1. HVEF contributed to the affinity for nitrate in all treatment groups. The affinity of cucumber seedlings for nitrate positively correlated with the intensity of the applied field as the field increased to 1.0 kV cm^-1. HVEF enabled the seedlings to opt to consume when two types of nitrogen were present in the nutrient solution. These results can be attributed to feedback adjustment and electron transportation in nitrogen assimilation.

Research on Direct Effects of High-Voltage Electrostatic Field on Lactoperoxidase's Activity

At present, indirect effects of high-voltage electrostatic field on organisms and biological materials have been extensively studied. However, the investigations on direct interaction between the electrostatic field and enzyme are scarce. In this paper, the direct effect of high-voltage electrostatic field on the LP and the protective effects of sucrose fatty acid ester on the activity of enzyme in high-voltage electrostatic field have been experimentally investigated. The results show that, high-voltage electrostatic field has direct effects on the LP and the best condition to enhance the activity of enzyme can be obtained. When the electric-field strength is low, with the increasing of the electric-field strength, the activity of the LP will be weakened. When the electric-field strength exceeds a certain level, the activity of the LP will be enhanced with the increasing of electric-field strength. For too higher electric-field strength , the activity of the LP will be again weakened with the increasing of electric-field strength. The sucrose fatty acid ester in low concentration provides a proper hydrophobic microenvironment for enzyme, which leads to the enhancement of enzyme's activity, while sucrose fatty acid ester in high concentration leads to the weakening of enzyme's activity. Moreover, sucrose fatty acid ester in enzyme solutions has protective effects on enzyme in the electric field and can reduce the impacts of high-voltage electrostatic field on the LP.

Effect of Electrohydrodynamic and Batch Drying on Rice Fissuring

The effects of high-voltage electrostatic field (10 kV), batch drying (45°C), and natural air-drying (26°C) on the impact strength of a brown rice kernel (Oryza Sativa L.) variety of Khazar were investigated under three levels of kinetic impact loading (10, 23, and 37 mJ) with 10 replications. Results showed that the effects of kinetic impact loading on the breakage susceptibility index (BSI) of artificially dried rice grains were significant at 1% confidence level. With increasing kinetic impact loading, the average value of BSI increased. The sound brown rice grains became stronger in natural air-drying as the drying duration increased at low drying temperatures. High-voltage electrostatic field and batch drying considerably increased the rate of breakage susceptibility but the EHD drying was inherently energy efficient with a low surface drying temperature.

The Effect of High-Voltage Electrostatic Field on the Water Performance

Water treated by external electric field with different field intensity. The absorbency of water, the changes of dyes solubility, the effect of treatment time and the changes of wool swelling were studied. The results showed that electric field treatments can alter the water physical properties to various degrees. The absorbance of water increased with increasing electric field intensity. The swelling ratio indicated the ability of solvent to penetrate the wool fibers and to swell them.

The effect of high-voltage electrostatic field (HVEF) on aged rice ( Oryza sativa L.) seeds vigor and lipid peroxidation of seedlings

The study of the effect of high-voltage electrostatic field (HVEF) on plant seeds has been becoming one of the popular issues in electrostatic biology since the influence of HVEF on growing plants was observed early in 1980s and a few studies showed that HVEF could increase seeds activity. In this study the aged rice seeds were treated in HVEF, and their vitality and associated physiological variables such as membrane lipid peroxidation and the protective enzyme system, such as superoxide dismutase (SOD: EC 1.15.1.1), peroxidase (POD: EC 1.11.1.7) and catalase (CAT: EC 1.11.1.6) were also investigated. The results showed that the activity index of aged rice seeds was significantly increased, and the leakage conductivity was decreased with the appropriate HVEF treatment. The treatment also elevated the activity of SOD, POD and CAT, which improved the penetrating capability of membrane, and adjusted the level of lipid peroxidation and lowered the content of malondialdehyde (MDA). We concluded that HVEF could elevate aged rice seeds vigor and improve membrane system of aged rice seedlings, and the treatment for 55 min was better than that of 30 min.

Effect of high-voltage electrostatic field on quality of carrot juice during refrigeration

In the present study, carrot juice was used as the experimental material and stored in a 100 kV/m high-voltage electrostatic field (HVEF; E-group) which was used as a freshness-retention system. The changes in the biological properties were investigated relative to those juices which were stored in a common refrigerator (R-group) and controlled at the same temperature (4 °C). The results showed that the extent of color difference (ΔE), amount of total phenolics, tannins, and total plate counts of carrot juice were increased during the storage period, whereas the turbidity and amount of total carotenoids decreased under all treatment conditions. These factors remained relatively constant during storage in the E-group, whereas a significant difference ( p < 0.05) was observed in the R-group. The HVEF treatment yielded better physicochemical properties and prolonged the shelf-life of the carrot juice. The application of HVEF at low temperature has the potential of imparting freshness and a high nutritional value to the products.

Positive effect of high voltage electrostatic field on the development of in vitro fertilized mouse embryos

In order to investigate the effect of high voltage electrostatic field (HVESF) on the preimplantation development of an in vitro fertilized (IVF) embryo, we used the mouse model to attempt at understanding the effect that HVESF may benefit preimplantation development. The optimal dosage (field intensity and treatment time) was selected according to the proportion of 1 or 2-cell embryos which developed into blastocysts or hatched blastocysts during in vitro culture. Using the optimal dosage treatment on mouse embryos, the effect of HVESF at different cell stages on their developmental potential was also investigated. The results showed that the HVESF can significantly promote the preimplantation development of embryos in vitro, at the optimal dosage stimulation the proportion of blastocysts increased from 42.4% to 67.5%, hatched blastocysts increased from 20.8% to 48.4% when compared to control, and there was significant difference between the optimal dosage group and control group. Different sensitivities existed among the embryos at different cell stage for HVESF, to which the 1 or 2-cell stage embryos were significantly more sensitive than others. Following, we have provided, to our knowledge, the first report of application of HVESF on mammalian embryology.