Differential mechanism between Listeria monocytogenes strains with different virulence contaminating ready-to-eat sausages during the simulated gastrointestinal tract.

Listeria monocytogenes exhibits varying levels of pathogenicity when entering the host through contaminated food. However, little is known regarding the stress response and environmental tolerance mechanism of different virulence strains to host gastrointestinal (GI) stimuli. This study analyzed the differences in the survival and genes of stress responses among two strains of L. monocytogenes 10403S (serotype 1/2a, highly virulent strain) and M7 (serotype 4a, low-virulence strain) during simulated gastrointestinal digestion. The results indicated that L. monocytogenes 10403S showed greater acid and bile salt tolerance than L. monocytogenes M7, with higher survival rates and less cell deformation and cell membrane permeability during the in vitro digestion. KEGG analysis of the transcriptomes indicated that L. monocytogenes 10403S displayed significant activity in amino acid metabolism, such as glutamate and arginine, associated with acid tolerance. Additionally, L. monocytogenes 10403S demonstrated a higher efficacy in promoting activities that preserve bacterial cell membrane integrity and facilitate flagellar protein synthesis. These findings will contribute valuable practical insights into the tolerance distinctions among different virulence strains of L. monocytogenes in the GI environment.

Modulating mycobacterial envelope integrity for antibiotic synergy with benzothiazoles.

Developing effective tuberculosis drugs is hindered by mycobacteria's intrinsic antibiotic resistance because of their impermeable cell envelope. Using benzothiazole compounds, we aimed to increase mycobacterial cell envelope permeability and weaken the defenses of Mycobacterium marinum, serving as a model for Mycobacterium tuberculosis Initial hit, BT-08, significantly boosted ethidium bromide uptake, indicating enhanced membrane permeability. It also demonstrated efficacy in the M. marinum-zebrafish embryo infection model and M. tuberculosis-infected macrophages. Notably, BT-08 synergized with established antibiotics, including vancomycin and rifampicin. Subsequent medicinal chemistry optimization led to BT-37, a non-toxic and more potent derivative, also enhancing ethidium bromide uptake and maintaining synergy with rifampicin in infected zebrafish embryos. Mutants of M. marinum resistant to BT-37 revealed that MMAR_0407 (Rv0164) is the molecular target and that this target plays a role in the observed synergy and permeability. This study introduces novel compounds targeting a new mycobacterial vulnerability and highlights their cooperative and synergistic interactions with existing antibiotics.

Antibacterial Activity and Mechanism of Action of Osthole against Listeria monocytogenes.

The purpose of this study was to investigate the antibacterial activity and mechanism of action of osthole against Listeria monocytogenes. The antibacterial activity of osthole was evaluated by determining the minimum inhibitory concentration (MIC) and growth curve. Cell morphology, membrane permeability, membrane integrity, bacterial physiology, and metabolism were explored using different methods to elucidate the mechanism of action of osthole. It was shown that the MIC of osthole against L. monocytogenes was 62.5 µg/mL and it inhibited the growth of L. monocytogenes effectively in a concentration-dependent manner. Scanning electron microscopy (SEM) images demonstrated morphology changes of L. monocytogenes, including rough surface, cell shrinkage, and rupture. It was found that extracellular conductivity and macromolecule content were increased significantly in the presence of osthole, indicating the disruption of cell membrane integrity and permeability. Laser confocal microscopy results supported the conclusion that osthole caused severe damage to the cell membrane. It was also noticed that osthole depleted intracellular adenosine triphosphate (ATP), inhibited Na+-K+-ATPase and Ca2+-Mg2+-ATPase activity, and promoted the accumulation of intracellular reactive oxygen species (ROS), leading to cell death. This study suggests that osthole is a promising antibacterial agent candidate against L. monocytogenes, and it shows potential in the prevention and control of foodborne pathogens.

Two promising natural lipopeptides from Bacillus subtilis effectively induced membrane permeabilization in Candida glabrata.

Candida glabrata is an important opportunistic human pathogen well known to develop resistance to antifungal drugs. Due to their numerous desirable qualities, antimicrobial lipopeptides have gained significant attention as promising candidates for antifungal drugs. In the present study, two bioactive lipopeptides (AF4 and AF5 m/z 1071.5 and 1085.5, respectively), coproduced and purified from Bacillus subtilis RLID12.1, consist of seven amino acid residues with lipid moieties. In our previous studies, the reversed phased-HPLC purified lipopeptides demonstrated broad-spectrum of antifungal activities against over 110 Candida albicans, Candida non-albicans and mycelial fungi. Two lipopeptides triggered membrane permeabilization of C. glabrata cells, as confirmed by propidium iodide-based flow cytometry, with PI uptake up to 99% demonstrating fungicidal effects. Metabolic inactivation in treated cells was confirmed by FUN-1-based confocal microscopy. Together, the results indicate that these lipopeptides have potentials to be developed into a new set of antifungals for combating fungal infections.

Estimating the Ca2+ Permeability of NMDA Receptors with Whole-Cell Patch-Clamp Electrophysiology.

In the mammalian central nervous system (CNS), fast excitatory transmission relies primarily on the ionic fluxes generated by ionotropic glutamate receptors (iGluRs). Among iGluRs, NMDA receptors (NMDARs) are unique in their ability to pass large, Ca2+-rich currents. Importantly, their high Ca2+ permeability is essential for normal CNS function and is under physiological control. For this reason, the accurate measurement of NMDA receptor Ca2+ permeability represents a valuable experimental step in evaluating the mechanism by which these receptors contribute to a variety of physiological and pathological conditions. In this chapter, we provide a theoretical and practical overview of the common methods used to estimate the Ca2+ permeability of ion channels as they apply to NMDA receptors. Specifically, we describe the principles and methodology used to calculate relative permeability (PCa/PNa) and fractional permeability (Pf), along with the relationship between these two metrics. With increasing knowledge about the structural dynamics of ion channels and of the ongoing environmental fluctuations in which channels operate in vivo, the ability to quantify the Ca2+ entering cells through specific ion channels remains a tool essential to delineating the molecular mechanisms that support health and cause disease.

Differential Bioactivation Profiles of Different GS-441524 Prodrugs in Cell and Mouse Models: ProTide Prodrugs with High Cell Permeability and Susceptibility to Cathepsin A Are More Efficient in Delivering Antiviral Active Metabolites to the Lung.

We assessed factors that determine the tissue-specific bioactivation of ProTide prodrugs by comparing the disposition and activation of remdesivir (RDV), its methylpropyl and isopropyl ester analogues (MeRDV and IsoRDV, respectively), the oral prodrug GS-621763, and the parent nucleotide GS-441524 (Nuc). RDV and MeRDV yielded more active metabolite remdesivir-triphosphate (RDV-TP) than IsoRDV, GS-621763, and Nuc in human lung cell models due to superior cell permeability and higher susceptivity to cathepsin A. Intravenous administration to mice showed that RDV and MeRDV delivered significantly more RDV-TP to the lung than other compounds. Nevertheless, all four ester prodrugs exhibited very low oral bioavailability (<2%), with Nuc being the predominant metabolite in blood. In conclusion, ProTides prodrugs, such as RDV and MeRDV, are more efficient in delivering active metabolites to the lung than Nuc, driven by high cell permeability and susceptivity to cathepsin A. Optimizing ProTides' ester structures is an effective strategy for enhancing prodrug activation in the lung.

[Evaluation of Solubility and Membrane Permeability of Middle-Molecule Compounds Using Artificial Membranes and Living Cells].

In contrast to small molecules, middle molecules present a promising therapeutic modality owing to their elevated specificity, minimal adverse effects, capacity to target protein-protein interactions, and, unlike antibody-based drugs, their suitability for oral administration and intracellular target engagement. Post-oral administration, the paramount considerations encompass solubility and membrane permeability during the initial phase until the drug attains systemic circulation. Furthermore, penetration of the cell membrane is essential to accessing intracellular targets. We evaluated the solubility and membrane permeability of 965 compounds sourced from middle molecule libraries affiliated with Hokkaido University, Kitasato University, and the University of Tokyo. To gauge membrane permeability, we employed both the parallel artificial membrane permeability assay (PAMPA) and Caco-2 cell monolayers. Notably, while membrane permeability in Caco-2 cells exhibited an approximate threefold increase in comparison to PAMPA measurements, certain compounds demonstrated permeability levels less than one-third of those observed in Caco-2 cells. Recognizing the potential involvement of efflux transporters expressed in Caco-2 cells in these variations, we conducted additional assessments involving directional transport in the presence of a transporter inhibitor. Our findings suggest that nearly 80% of these compounds serve as substrates for efflux transporters. Considering the relevance of intracellular targets, we shifted our focus from membrane permeation to intracellular uptake, conducting simulations tailored to assess cellular uptake.

[Development of Membrane Permeability Coefficient by Means of Novel Molecular Dynamics Methods].

The membrane permeability, and its evaluation, is crucial factor in the process of uptake of compounds from outside to inside the cell and in the inhibition of the activity of disease-causing target proteins. Although molecular dynamics (MD) simulations have been shown to be able to reproduce the conformational changes of compounds occurring during membrane permeation, it is still challenging to extract the membrane permeability at an affordable computational workload solely by conventional MD. Indeed, the time scale accessible by MD is far below the one characterizing the actual permeation process. Phenomena occurring in living organisms escaping the reach of standard MD are generally referred to as biological rare events, and the membrane permeation process is one of them. To overcome this time-scale problem, several enhanced sampling methods have been proposed over the years to improve conformational sampling. In this review, a hybrid sampling method that combines the parallel cascade selection MD (PaCS-MD) and the outlier flooding method (OFLOOD), introduced and developed by our group, is proposed as a tool to study the membrane permeation from structural sampling (rare-event sampling). The obtained trajectories are used to estimate the free energy profiles for the membrane permeation and to compute the membrane permeation coefficients. Moreover, we present an example of application of the free energy reaction network method as a versatile way for incorporating explicitly into reaction coordinates the degrees of freedom related to internal motion.

The 6-kilodalton peptide 1 in plant viruses of the family Potyviridae is a viroporin.

Potyviridae, the largest family of plant RNA viruses, includes many important pathogens that significantly reduce the yields of many crops worldwide. In this study, we report that the 6-kilodalton peptide 1 (6K1), one of the least characterized potyviral proteins, is an endoplasmic reticulum-localized protein. AI-assisted structure modeling and biochemical assays suggest that 6K1 forms pentamers with a central hydrophobic tunnel, can increase the cell membrane permeability of Escherichia coli and Nicotiana benthamiana, and can conduct potassium in Saccharomyces cerevisiae. An infectivity assay showed that viral proliferation is inhibited by mutations that affect 6K1 multimerization. Moreover, the 6K1 or its homologous 7K proteins from other viruses of the Potyviridae family also have the ability to increase cell membrane permeability and transmembrane potassium conductance. Taken together, these data reveal that 6K1 and its homologous 7K proteins function as viroporins in viral infected cells.

Transcriptomics Studies Reveal Functions of Transglutaminase 2 in Breast Cancer Cells Using Membrane Permeable and Impermeable Inhibitors.

Transglutaminase 2 (TG2) performs many functions both under physiological and pathological conditions. In cancer, its expression is associated with aggressiveness, propensity to epithelial-mesenchymal transition, and metastasis. Since TG2 performs key functions both outside and inside the cell, using inhibitors with different membrane permeability we analyzed the changes in the transcriptome induced in two triple-negative cell lines (MDA-MB-436 and MDA-MB-231) with aggressive features. By characterizing pathways and gene networks, we were able to define the effects of TG2 inhibitors (AA9, membrane-permeable, and NCEG2, impermeable) in relation to the roles of the enzyme in the intra- and extracellular space within the context of breast cancer. The deregulated genes revealed p53 and integrin signaling to be the common pathways with some genes showing opposite changes in expression. In MDA-MB-436, AA9 induced apoptosis, modulated cadherin, Wnt, gastrin and cholecystokinin receptors (CCKR) mediated signaling, with RHOB and GNG2 playing significant roles, and affected the Warburg effect by decreasing glycolytic enzymes. In MDA-MB-231 cells, AA9 strongly impacted HIF-mediated hypoxia, including AKT and mTOR pathway. These effects suggest an anti-tumor activity by blocking intracellular TG2 functions. Conversely, the use of NCEG2 stimulated the expression of ATP synthase and proteins involved in DNA replication, indicating a potential promotion of cell proliferation through inhibition of extracellular TG2. To effectively utilize these molecules as an anti-tumor strategy, an appropriate delivery system should be evaluated to target specific functions and avoid adverse effects. Additionally, considering combinations with other pathway modulators is crucial.

Gaussian accelerated molecular dynamics simulations facilitate prediction of the permeability of cyclic peptides.

Despite their widespread use as therapeutics, clinical development of small molecule drugs remains challenging. Among the many parameters that undergo optimization during the drug development process, increasing passive cell permeability (i.e., log(P)) can have some of the largest impact on potency. Cyclic peptides (CPs) have emerged as a viable alternative to small molecules, as they retain many of the advantages of small molecules (oral availability, target specificity) while being highly effective at traversing the plasma membrane. However, the relationship between the dominant conformations that typify CPs in an aqueous versus a membrane environment and cell permeability remain poorly characterized. In this study, we have used Gaussian accelerated molecular dynamics (GaMD) simulations to characterize the effect of solvent on the free energy landscape of lariat peptides, a subset of CPs that have recently shown potential for drug development (Kelly et al., JACS 2021). Differences in the free energy of lariat peptides as a function of solvent can be used to predict permeability of these molecules, and our results show that permeability is most greatly influenced by N-methylation and exposure to solvent. Our approach lays the groundwork for using GaMD as a way to virtually screen large libraries of CPs and drive forward development of CP-based therapeutics.

A translocation fluorescent probe for analyzing cellular physiological parameters in neurological disease models.

Neurological disorders are closely linked to the alterations in cell membrane permeability (CMP) and mitochondrial membrane potential (MMP). Changes in CMP and MMP may lead to damage and death of nerve cells, thus triggering the onset and progression of neurological diseases. Therefore, monitoring the changes of these two physiological parameters not only benefits the accurate assessment of nerve cell health status, but also enables providing key information for the diagnosis and treatment of neurological diseases. However, the simultaneous monitoring of these two cellular physiological parameters is still challenging. Herein, we design and synthesize two quinolinium-carbazole-derivated fluorescent probes (OQ and PQ). As isomers, the only difference in their chemical structures is the linking position of the carbazole unit in quinoline rings. Strikingly, such a subtle difference endows OQ and PQ with significantly different organelle-staining behaviors. PQ mainly targets at the nucleus, OQ can simultaneously stain cell membranes and mitochondria in normal cells, and performs CMP and MMP-dependent translocation from the cell membrane to mitochondria then to the nucleus, thus holding great promise as an intracellular translocation probe to image the changes of CMP and MMP. After unraveling the intrinsic mechanism of their different translocation abilities by combining experiments with molecular dynamics simulations and density functional theory calculations, we successfully used OQ to monitor the continuous changes of CMP and MMP in three neurological disease-related cell models, including oxidative stress-damaged, Parkinson's disease, and virus-infected ones. Besides providing a validated imaging tool for monitoring cellular physiological parameters, this work paves a promising route for designing intracellular translocation probes to analyze cellular physiological parameters associated with various diseases.

Bioluminescence-Based Determination of Cytosolic Accumulation of Antibiotics in Escherichia coli.

Antibiotic resistance is an alarming public health concern that affects millions of individuals across the globe each year. A major challenge in the development of effective antibiotics lies in their limited ability to permeate cells, noting that numerous susceptible antibiotic targets reside within the bacterial cytosol. Consequently, improving the cellular permeability is often a key consideration during antibiotic development, underscoring the need for reliable methods to assess the permeability of molecules across cellular membranes. Currently, methods used to measure permeability often fail to discriminate between the arrival within the cytoplasm and the overall association of molecules with the cell. Additionally, these techniques typically possess throughput limitations. In this work, we describe a luciferase-based assay designed for assessing the permeability of molecules in the cytosolic compartment of Gram-negative bacteria. Our findings demonstrate a robust system that can elucidate the kinetics of intracellular antibiotic accumulation in live bacterial cells in real time.

Generating Concentration Gradients across Membranes for Molecular Dynamics Simulations of Periodic Systems.

The plasma membrane forms the boundary between a living entity and its environment and acts as a barrier to permeation and flow of substances. Several computational means of calculating permeability have been implemented for molecular dynamics (MD) simulations-based approaches. Except for double bilayer systems, most permeability studies have been performed under equilibrium conditions, in large part due to the challenges associated with creating concentration gradients in simulations utilizing periodic boundary conditions. To enhance the scientific understanding of permeation and complement the existing computational means of characterizing membrane permeability, we developed a non-equilibrium method that enables the generation and maintenance of steady-state gradients in MD simulations. We utilize PBCs advantageously by imposing a directional bias to the motion of permeants so that their crossing of the boundary replenishes the gradient, like a previous study on ions. Under these conditions, a net flow of permeants across membranes may be observed to determine bulk permeability by a direct application of J=PΔc. In the present study, we explore the results of its application to an exemplary O2 and POPC bilayer system, demonstrating accurate and precise permeability measurements. In addition, we illustrate the impact of permeant concentration and the choice of thermostat on the permeability. Moreover, we demonstrate that energetics of permeation can be closely examined by the dissipation of the gradient across the membrane to gain nuanced insights into the thermodynamics of permeability.

Ultrastructural examination of cryodamage in Paracentrotus lividus eggs during cryopreservation.

This study examinates the challenges of cryopreserving sea urchin (Paracentrotus lividus) eggs, a task hindered by factors like low membrane permeability and high sensitivity to cryoprotective agents (CPAs). While successful cryopreservation has been achieved for some marine invertebrates, eggs remain problematic due to their unique characteristics. The study explores the impact of various CPAs and cryopreservation techniques on sea urchin eggs, employing scanning and transmission electron microscopy to analyze cellular damage. The findings reveal that exposure to low CPA concentrations (0.5 M) did not induce significant damage to eggs. However, high concentrations (3 M) proved highly detrimental. Every cryopreservation approach investigated in this study resulted in irreversible damage to the sea urchin eggs, rendering them nonviable for future use. The research sheds light on the importance of understanding the structural alterations induced by CPAs and cryopreservation methods. This knowledge is essential for refining cryopreservation methods, potentially paving the way for successful preservation of these challenging cells.

Discovery of indolylacryloyl-derived oxacins as novel potential broad-spectrum antibacterial candidates.

The emergence of serious bacterial resistance towards clinical oxacins poses a considerable threat to global public health, necessitating the development of novel structural antibacterial agents. Seven types of novel indolylacryloyl-derived oxacins (IDOs) were designed and synthesized for the first time from commercial 3,4-difluoroaniline via an eight-step procedure. The synthesized compounds were characterized by modern spectroscopic techniques. All target molecules were evaluated for antimicrobial activities. Most of the prepared IDOs showed a broad antibacterial spectrum and strong activities against the tested strains, especially ethoxycarbonyl IDO 10d (0.25-0.5 µg/mL) and hydroxyethyl IDO 10e (0.25-1 µg/mL) exhibited much superior antibacterial efficacies to reference drug norfloxacin. These highly active IDOs also displayed low hemolysis, cytotoxicity and resistance, as well as rapid bactericidal capacity. Further investigations indicated that ethoxycarbonyl IDO 10d and hydroxyethyl IDO 10e could effectively reduce the exopolysaccharide content and eradicate the formed biofilm, which might delay the development of drug resistance. Preliminary exploration of the antibacterial mechanism revealed that active IDOs could not only destroy membrane integrity, resulting in changes in membrane permeability, but also promote the accumulation of reactive oxygen species, leading to the production of malondialdehyde and decreased bacterial metabolism. Moreover, they exhibited the capability to bind with DNA and DNA gyrase, forming supramolecular complexes through various noncovalent interactions, thereby inhibiting DNA replication and causing bacterial death. All the above results suggested that the newly developed indolylacryloyl-derived oxacins should hold great promise as potential multitargeting broad-spectrum antibacterial candidates to overcome drug resistance.

Interaction of selected alkoxy naringenin oximes with model and bacterial membranes.

Naringenin is a flavonoid found in many fruits and herbs, most notably in grapefruits. In recent years, this compound and its derivatives have been of great interest due to their high biological activity, including fungicidal and bactericidal effects, also in relation to multidrug-resistant bacteria. Membrane interactions of naringenin oxime (NO) and its 7-O-alkyl (7-alkoxy) derivatives, such as methyl (7MENO), ethyl (7ETNO), isopropyl (7IPNO), n-butyl (7BUNO) and n-pentyl (7PENO) were studied. Thermotropic properties of model membranes were investigated via differential scanning calorimetry (DSC), the influence on lipid raft mimicking giant unilamellar vesicles (GUVs) via fluorescence microscopy, and membrane permeability via measuring calcein leakage from liposomes. Molecular calculations supplemented the study. The influence of naringenin oximes on two strains of multidrug resistant bacteria: Staphylococcus aureus KJ and Enterococcus faecalis 37VRE was also investigated. In DSC studies all compounds reduced the temperature and enthalpy of main phase transition and caused disappearing of the pretransition. NO was the least active. The reduction in the area of surface domains in GUVs was observed for NO. Compounds NO and 7BUNO resulted in very low secretion of calcein from liposomes (permeability < 3 %). The highest results were observed for 7MENO (88.4 %) and 7IPNO (78.5 %). When bacterial membrane permeability was investigated all compounds caused significant release of propidium iodide from S. aureus (31.6-87.0 % for concentration 128 µg/mL). In the case of E. faecalis, 7ETNO (75.7 %) and NO (28.8 %) were the most active. The rest of the tested compounds showed less activity (permeability < 13.9 %). The strong evidence was observed that antibacterial activity of the tested compounds may be associated with their interaction with bacterial membrane.

Application of cuminaldehyde and ciprofloxacin for the effective control of biofilm assembly of Pseudomonas aeruginosa: A combinatorial study.

Pseudomonas aeruginosa is widely associated with biofilm-mediated antibiotic resistant chronic and acute infections which constitute a persistent healthcare challenges. Addressing this threat requires exploration of novel therapeutic strategies involving the combination of natural compounds and conventional antibiotics. Hence, our study has focused on two compounds; cuminaldehyde and ciprofloxacin, which were strategically combined to target the biofilm challenge of P. aeruginosa. The minimum inhibitory concentration (MIC) of cuminaldehyde and ciprofloxacin was found to be 400 µg/mL and 0.4 µg/mL, respectively. Moreover, the fractional inhibitory concentration index (FICI = 0.62) indicated an additive interaction prevailed between cuminaldehyde and ciprofloxacin. Subsequently, sub-MIC doses of cuminaldehyde (25 µg/mL) and ciprofloxacin (0.05 µg/mL) were selected for an array of antibiofilm assays which confirmed their biofilm inhibitory potential without exhibiting any antimicrobial activity. Furthermore, selected doses of the mentioned compounds could manage biofilm on catheter surface by inhibiting and disintegrating existing biofilm. Additionally, the test combination of the mentioned compounds reduced virulence factors secretion, accumulated reactive oxygen species and increased cell-membrane permeability. Thus, the combination of cuminaldehyde and ciprofloxacin demonstrates potential in combating biofilm-associated Pseudomonal threats.

Multiparametric Analysis of Apoptosis by Flow Cytometry.

Flow cytometry remains the most widely used method for detecting and quantifying apoptosis and related forms of cell death in mammalian cells. The multiparametric nature of flow cytometry allows multiple apoptotic characteristics to be labeled and analyzed in a single sample, making it a powerful tool for analyzing the complex progression of apoptotic death. This chapter provides methods for combining assays for single apoptotic characteristics like caspase activation, annexin V binding, and cell membrane permeability into multiparametric assays that provide deeper insights into the cell death process. This approach to analyzing multiple apoptotic characteristics simultaneously yields far more information than single-parameter assays. While more informative than single-parameter assays, these multicolor methods can still be analyzed on relatively simple flow cytometers, making them widely accessible.

Study on the effect of different high-voltage electric field polarization process parameters on the vitality of dried chili pepper seeds.

To study the effect of different high-voltage electric field polarisation treatment process parameters on the viability of seeds of dried chili peppers. In this study, a high-voltage electrostatic polarisation treatment system was constructed to carry out experiments on the effects of different high-voltage electric field polarisation treatment process parameters on the viability of dried chili seeds. Conduct one-way tests to determine the preferred polarisation method and the preferred interval for output voltage and polarisation time. Two-factor, five-level central combination test with output voltage and polarization time as test factors and seed conductivity as a response indicator. Determining the better combination of parameters for output voltage and polarization time; Conducting seed germination trials to validate the effectiveness of the polarisation process. The results of the one-way test showed that: Negative-voltage polarisation was more effective than positive-voltage polarisation and alternating positive-negative-voltage polarisation in promoting seed vigor, with a better output voltage in the range of 10-14 kV, and a better polarisation time in the range of 20-40 s; The results of orthogonal tests showed that: Under the condition of negative voltage polarisation treatment, the output voltage of 12.08 kV and polarisation time of 30.32 s was the better parameter combination, at which the seed conductivity was minimum 159.87 uS/(cm g). Analyzing the function of cell membrane selective semi-permeability by seed conductivity change and revealing the mechanism of seed viability enhancement by high voltage electric field polarisation treatment; In the seed germination test, compared with the control group, seed germination potential increased by 9.09%, germination rate increased by 20.45%, germination index increased by 3.49, and vigor index increased by 41.66 under high-voltage electrostatic polarisation treatment, and all vigor indexes were significantly improved. The results of this study can provide a basis for the selection of processes and parameters for subsequent high-voltage electric field polarisation treatment of crop seeds.