Search Results (17)

Fresh vegetables, especially green onions and chives, are raw ingredients widely consumed by Koreans, and have been linked to Listeria monocytogenes-induced food poisoning. This study aimed to assess microbial contamination levels in commercially available fresh-cut vegetables and produce, compare the effects of different types and concentrations of disinfectants on green onions and chives, and determine the growth rate of L. monocytogenes on chives under different storage conditions. Among the five fresh-cut vegetable mix salad products, the average total mesophilic count (TMC) was 2.00 log CFU/g, whereas the crown daisies exhibited the highest levels of raw produce contamination (TMC of 4.14 log CFU/g). The disinfection experiments indicated the elevated disinfectant capacities of electrolyzed water as well as washing under running water against Escherichia coli and L. monocytogenes. Enhanced anti-TMC ability of electrolyzed water were observed in acidic 30 ppm (pH 3.2) and 60 ppm (pH 5.6) of HOCl, and alkaline 100 ppm (pH 8.1) and 200 ppm (pH 8.8) of NaClO. Moreover, in the L. monocytogenes inoculation experiment in chive, the growth rates at 5 °C, 12 °C, and 30 °C were −0.002, 0.023, and 0.030 log CFU/g/h, respectively. This observation suggests that L. monocytogenes cannot grow on chives if stored at 5 °C but can at 12 °C. This study provides scientific evidence to guide the management of microbial quality of fresh produce and fresh-cut vegetables for safer meal provision in home and eating-out settings. Full article

Salt stress causes harm to plants through multiple aspects, such as osmotic pressure, ion poisoning, nutrient imbalance, and oxidative damage. Zinc finger proteins harboring two B-box domains, known as double B-box (DBB) proteins, constitute the DBB family. While DBB genes have been implicated in regulating circadian rhythms and stress responses in various plant species, their functions in cotton remain largely unexplored. The present study characterized the DBB gene family across the genomes of Gossypium hirsutum L., Gossypium raimondii L., and Gossypium arboreum L., revealing a complement of 58 members. These DBB genes were assigned to three separate clades based on phylogenetic analysis. Members possessing close phylogenetic relationships have similar conserved protein motifs and gene structures. All DBB proteins were predicted to be nuclear-localized, consistent with their roles as transcription factors. Furthermore, the presence of multiple cis-acting elements related to light, hormone, and stress responses in the promoters implies that GhDBBs are integral to cotton’s environmental stress adaptation. Expression pattern analysis indicated that the expression of GhDBB genes was associated with the plant’s response to multiple abiotic stresses, such as salt, drought, heat (37 °C), and cold (4 °C). The reliability of the expression data was confirmed by qPCR analysis of eight selected GhDBBs. Under 200 mM NaCl, Arabidopsis plants overexpressing GhDBB22 displayed longer roots and healthier true leaves than the wild-type controls. Conversely, VIGS-mediated silencing of GhDBB22 in G. hirsutum led to significantly reduced salt tolerance, accompanied by exacerbated oxidative damage. Taken together, the findings from our integrated genomic and functional analyses provide a foundational understanding of the molecular mechanisms through which proteins encoded by DBB genes are involved in the plant’s response to salt stress. Full article

Staphylococcal food poisoning (SFP) is a common foodborne illness caused by the ingestion of enterotoxins produced by Staphylococcus aureus, posing a persistent global public health concern. Although regional differences in implicated food types and predominant enterotoxins have been reported, the underlying factors remain unclear. In this study, we systematically investigated the effects of nutritional factors on the growth, biofilm formation, and production of two representative enterotoxins, SEA and SEB, by S. aureus. Specifically, we evaluated bacterial responses to different concentrations of NaCl, glucose, and tryptone. NaCl suppressed growth, biofilm formation and enterotoxin production in a dose-dependent manner. Glucose markedly inhibited both bacteria growth and enterotoxin production, with a stronger effect on SEB than SEA. In contrast, tryptone promoted bacterial growth and moderately enhanced biofilm formation but did not significantly affect enterotoxin production. Importantly, even under comparable bacterial counts, the types and amounts of SEs produced varied substantially depending on the nutrient composition. These findings provide new insights into the nutrient-dependent regulation of virulence in S. aureus and highlight the importance of considering environmental and nutritional factors when assessing risks of SFP and designing effective food safety strategies. Full article

Foodborne pathogens represent a class of pathogenic microorganisms capable of causing food poisoning or serving as foodborne vectors, constituting a major source of food safety concerns. With increasing demands for rapid diagnostics, conventional culture-based methods and PCR assays face limitations due to prolonged turnaround times and specialized facility requirements. While CRISPR-based detection has emerged as a promising rapid diagnostic platform, its inherent inability to detect low-abundance targets necessitates coupling with isothermal amplification, thereby increasing operational complexity. In this study, we preliminarily developed a novel amplification-free Cascade-CRISPR detection system utilizing a hairpin DNA amplifier. This method achieves detection sensitivity as low as 10 fM (82 parasites/μL) for DNA targets within 30 min without requiring pre-amplification, with background signal suppression achieved through optimized NaCl concentration. Validation using artificially contaminated food samples demonstrated the platform’s robust performance for both Toxoplasma gondii (T. gondii) and Listeria monocytogenes (L. monocytogenes) detection, confirming broad applicability. In summary, this study preliminarily establishes an amplification-free Cascade-CRISPR detection platform that achieves high sensitivity and rapid turnaround, demonstrating strong potential for on-site screening of foodborne pathogens. Full article

Marine biofouling causes significant economic losses, and conventional antifouling methods are often associated with environmental pollution. Hydrogen peroxide (H₂O₂), as a clean energy source, has gained increasing attention in recent years. Meanwhile, electrocatalytic 2e⁻ oxygen reduction reaction (ORR) for H₂O₂ production has received growing interest. However, the majority of current studies are conducted on acidic or alkaline electrolytes, and research on 2e⁻ ORR in neutral NaCl solutions remains rare. Here, a bimetallic Zn-Cd zeolitic imidazolate framework (ZnCd-ZIF) is rationally designed to achieve chloride-resistant 2e⁻ ORR catalysis under simulated seawater conditions (pH 7.5, 3.5% Cl⁻). Experimental results demonstrate that the ZnCd-ZIF catalyst exhibits an exceptional H₂O₂ selectivity of 70% at 0.3 V_RHE, surpassing monometallic Zn-ZIF (60%) and Cd-ZIF (50%). Notably, H₂O₂ production reaches 120 mmol g⁻¹ in a Cl⁻-containing neutral electrolyte, exhibiting strong resistance to structural corrosion and Cl⁻ poisoning. This work not only pioneers an effective strategy for designing ORR catalysts adapted to marine environments but also advances the practical implementation of seawater-based electrochemical H₂O₂ synthesis. Full article

Oak poisoning is a known intoxication in grazing animals, but is slightly described in the literature. This case report describes 7 cattle from 3 different farms admitted to the clinic for ruminants of the University of Liège for suspected acorn poisoning in the autumn of 2022. The clinical signs were, anorexia, apathy with polyuria with low density. Further investigations led to the diagnosis of renal failure (blood urea 162 ± 88 mg/dL; blood creatinine 12 ± 4 mg/L). Supportive treatment, based on infusions (NaCl 0.9%) and electrolyte rebalancing, was administered and renal values were assessed every 24–48 h. Of these animals, 5/7 were euthanized. At necropsy, digestive erosions and ulcerations, oedema and renal hemorrhages, between the pyloric/caliceal cavity and the medulla were observed. Histopathological examination revealed necrosis of the renal tubules. The renal values of the two remaining animals were reduced, their general condition improved, and they were discharged. Acorn poisoning is a serious disease with no specific antidote or characteristic symptoms. Animals are identified as sick too late, when renal failure is already established. Farmers should be made more aware in order to prevent exposure, especially in years when acorns are abundant. Furthermore, there is no antidote for this intoxication. Full article

Abiotic stresses such as salt stress seriously affect the growth and yield of plants. Tamarix ramosissima Lcdcb (T. ramosissima) is a widely cultivated halophyte in saline-alkali areas of the world. As an essential element for plant growth and development, K⁺ plays an irreplaceable role in improving the tolerance of plants to salt stress. However, there are few reports on the mechanism of K⁺ in promoting plant hormones to reduce the damage of NaCl stress to T. ramosissima. In this study, we sequenced the transcriptome of the roots of T. ramosissima which were treated with exogenous potassium (K⁺) for 0 h, 48 h and 168 h under NaCl stress, according to the changes in the expression levels of differentially expressed genes (DEGs) in T. ramosissima roots. Key candidate genes and metabolic pathways related to plant hormones were mined for analysis and further verified by quantitative real-time PCR (qRT-PCR). The results showed that under NaCl stress for 48 h and 168 h, there were a large number of DEGs in the roots of T. ramosissima, and the expression levels changed over time. In particular, we found that 56 plant hormone-related genes were annotated to the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway, and with the increase of time, their expression levels were mainly up-regulated and involved in the related metabolic pathways to resist NaCl stress. It is worth noting that 7 DEGs related to abscisic acid (ABA), 28 DEGs related to auxin, 1 DEG related to ethylene (ET), and 1 DEG related to cytokinin (CK) were added within 168 h of exogenous potassium, and they were involved in alleviating the root damage of T. ramosissima under NaCl stress and played an important role. In addition, we found the plant hormone signal transduction pathway, which plays an important role in resistance to NaCl stress. As a result of this study, the molecular mechanism of plant hormones involved in applying exogenous potassium under NaCl stress is further understood, resulting in a better understanding of how exogenous potassium can alleviate the damage caused by NaCl under stress in T. ramosissima. Full article

Saline soil is a worldwide distributed resource that seriously harms plants’ growth and development. NaCl is the most widely distributed salt in saline soil. As a typical representative of halophytes, Tamarix ramosissima Lcdcb (T. ramosissima) is commonly grown in salinized soil, and halophytes have different abilities to retain more K⁺ under salt stress conditions. Halophytes can adapt to different salt environments by improving the scavenging activity of reactive oxygen species (ROS) by absorbing and transporting potassium (K⁺). In this study, electron microscope observation, hydrogen peroxide (H₂O₂) and malondialdehyde (MDA) contents determination, primary antioxidant enzyme activity determination and transcriptome sequencing analysis were carried out on the leaves of T. ramosissima under NaCl stress at 0 h, 48 h and 168 h. The results showed that H₂O₂ and MDA contents increased in the 200 mM NaCl + 10 mM KCl and 200 mM NaCl groups, but the content increased the most in the 200 mM NaCl group at 168 h. In addition, the leaves of T. ramosissima in the 200 mM NaCl + 10 mM KCl group had the most salt secretion, and its superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) activities were all higher than those of the 200 mM NaCl group and significantly higher than those of the control group. According to the results of transcriptome sequencing, it was found that the expression of 39 genes related to antioxidant enzyme activity changed significantly at the transcriptional level. Among them, 15 genes related to antioxidant enzyme activities were upregulated, and 24 genes related to antioxidant enzyme activities were downregulated in the leaves of T. ramosissima when exogenous potassium (K⁺) was applied under NaCl stress for 48 h; when exogenous potassium (K⁺) was used for 168 h under NaCl stress, 21 antioxidant enzyme activity-related genes were upregulated, and 18 antioxidant enzyme activity-related genes were downregulated in T. ramosissima leaves. Based on the changes of expression levels at different treatment times, 10 key candidates differentially expressed genes (DEGs) (Unigene0050462, Unigene0014843, Unigene0046159, Unigene0046160, Unigene0008032, Unigene0048033, Unigene0004890, Unigene0015109, Unigene0020552 and Unigene0048538) for antioxidant enzyme activities were further screened. They played an important role in applying exogenous potassium (K⁺) for 48 h and 168 h to the leaves of T. ramosissima in response to NaCl stress. Their expression levels were dominated by upregulation, which enhanced the activity of antioxidant enzymes, and helped T. ramosissima mitigate NaCl poison and resist NaCl stress. Particularly, Unigene0048538 in glutathione S-transferase (GST) activity had the largest log₂ fold-change in the comparison groups of 200 mM NaCl-48 h vs. 200 mM NaCl + 10 mM KCl-48 h and 200 mM NaCl-168 h vs. 200 mM NaCl + 10 mM KCl-168 h. Its expression level was upregulated and played an important role in NaCl toxicity. At the same time, the results of the phylogenetic tree analysis showed that Unigene0048538 had the closest genetic distance to Prunus persica in the evolutionary relationship. In summary, with the increase of exogenous potassium (K⁺) application time under NaCl stress, T. ramosissima can resist high NaCl stress by enhancing antioxidant enzymes’ activity and maintaining the growth of T. ramosissima. Still, it is not enough to completely eliminate NaCl poison. This study provides a theoretical basis for the molecular mechanism of salt tolerance and K⁺ mitigation of NaCl poison by the representative halophyte T. ramosissima in response to NaCl stress. Full article

Soil salinization is one of the main environmental factors affecting plant growth worldwide. Tamarix ramosissima Ledeb. (T. ramosissima) is a halophyte representative that is widely grown in salinized soils. As an important nutrient element for plant growth, K⁺ plays an important role in improving the tolerance to salt stress, but the mechanism of reducing the damage caused by NaCl stress to T. ramosissima is less reported. Our results show that the proline content and the Log₂ fold-change of proline’s relative quantification in the roots of T. ramosissima increased over time with the application of exogenous potassium (K⁺) for 48 h and 168 h under NaCl stress. Moreover, 13 amino-acid-related metabolic pathways were involved in the resistance of T. ramosissima to salt stress. Mainly, the aldehyde dehydrogenase family genes and tryptophan-synthase-related genes were found at 48 h and 168 h with exogenous potassium applied to the roots of T. ramosissima under NaCl stress, and they regulated their related metabolic accumulation in the arginine and proline metabolism pathways, increasing the effectiveness of inducing NaCl tolerance of T. ramosissima. It is noteworthy that alpha-ketobutyric was produced in the roots of T. ramosissima under NaCl stress for 48 h with the application of exogenous potassium, which is one of the most effective mechanisms for inducing salt tolerance in plants. Meanwhile, we found three DEGs regulating alpha-ketobutyric acid. This study provides a scientific theoretical basis for further understanding the molecular mechanism of K⁺ alleviating the salinity damage to T. ramosissima caused by NaCl. Full article

The purpose of this pilot study was to determine the role played by eosinophils in NaCl poisoning and right cardiac hypertrophy (ascitic syndrome) in Leghorn chickens, as well as the histological findings in the central nervous system (CNS), liver, and kidney. Moreover, the hypertrophy of the right ventricle index (HRVI) as an indicator of ascites was evaluated. Male SPF Leghorn birds at 28 days of age were submitted to two experiments. Food and water (FW) experiment: birds were treated with food plus 3.3% NaCl for the next 27 days and 1% NaCl in their drinking water from days 22 to 27. Water experiment (W): birds were treated with 1% NaCl in their drinking water for 5 days. In both experiments, the chickens exhibited loss of appetite, diuresis, and watery, green diarrhea during treatment days; at 24–27 td-FW and experiment W, the birds showed nervous signology (prostration, running movements, tremors, and comatose state). In the leukogram at 28 td-FW, an increase (p < 0.05) in heterophiles and basophils was observed. CNS eosinophilia was not observed in birds intoxicated with NaCl, though they did present demyelination in the brain and spinal cord, hepatic degeneration, mesangial proliferative glomerulopathy, and acute proximal renotubular necrosis. Full article

Cultures of the mussel Mytilus galloprovincialis are frequently affected by accumulation of the amnesic shellfish poisoning toxin domoic acid (DA). This species is characterized by a fast uptake and release of the toxin. In this work, the main characteristics of the uptake mechanism have been studied by incubation of digestive gland thin slices in media with different composition and DA concentration. DA uptake seems to follow Michaelis–Menten kinetics, with a very high estimated K_M (1722 µg DA mL⁻¹) and a V_max of 71.9 µg DA g⁻¹ h⁻¹, which is similar to those found for other amino acids in invertebrates. Replacement of NaCl from the incubation media by Cl-choline (Na⁺-free medium) did not significantly reduce the uptake, but replacement by sorbitol (Na⁺-free and Cl⁻-depleted medium) did. A new experiment replacing all chlorides with their equivalent gluconates (Na⁺- and Cl⁻-free medium) showed an important reduction in the uptake that should be attributed to the absence of chloride, pointing to a Na⁺-independent, Cl⁻ (or anion-) dependent transporter. In media with Na⁺ and Cl⁻, neither decreasing the pH nor adding cyanide (a metabolic inhibitor) had significant effect on DA uptake, suggesting that the transport mechanism is not H⁺- or ATP-dependent. In a chloride depleted medium, lowering pH or adding CN increased the uptake, suggesting that other anions could, at least partially, substitute chloride. Full article

Carbon monoxide (CO) is a commonly poisonous gas. It is important to detect CO in daily life. Herein, a new and sensitive surface enhanced Raman scattering (SERS) and resonance Rayleigh scattering (RRS) coupled di-mode method was developed for CO, based on gold nano-enzyme catalysis and gold nanoprobes. CO can react with HAuCl₄ to generate gold nanoparticles (AuNPs) in pH 5.2 HAc-NaAc buffer. The generated AuNPs exhibited SERS activity at 1620 cm⁻¹ in the presence of Vitoria blue B (VBB) molecular probes, and an RRS peak at 290 nm. Based on the AuNP bifunctional probes, the increased SERS and RRS intensities respond linearly with the concentration of CO in the range of 100–1500 ng/mL and 30–5230 ng/mL, respectively. To improve the sensitivity, the produced AuNPs were used as nano-enzyme catalysts for the new indicator reaction of HAuCl₄-ethanol (En) to amplify the signal. The sensitive SERS method was coupled with the accurate RRS method to develop a sensitive and accurate SERS/RRS di-mode method for determination of 3.0–413 ng/mL CO, based on the AuNP-HAuCl₄-En nanocatalytic reaction and its product of AuNPs as SERS and RRS bifunctional probes. Full article

The Clostridium sp. is a large group of spore-forming, facultative or strictly anaerobic, Gram-positive bacteria that can produce food poisoning. The table olive industry is demanding alternative formulations to respond to market demand for the reduction of acidity and salt contents in final products. while maintaining the appearance of freshness of fruits. In this work, logistic regression models for non-adapted and acid-adapted Clostridium sp. strains were developed in laboratory medium to study the influence of pH, NaCl (%) and time on the probability of germination of their spores. A Clostridium sporogenes cocktail was not able to germinate at pH < 5.0, although the adaptation of the strains produced an increase in the probability of germination at 5.0–5.5 pH levels and 6% NaCl concentration. At acidic pH values (5.0), the adapted strains germinated after 10 days of incubation, while those which were non-adapted required 15 days. At pH 5.75 and with 4% NaCl, germination of the adapted strains took place before 7 days, while several replicates of the non-adapted strains did not germinate after 42 days of storage. The model was validated in natural green olive brines with good results (>81.7% correct prediction cases). The information will be useful for the industry and administration to assess the safety risk in the formulation of new processing conditions in table olives and other fermented vegetables. Full article

Bacillus cereus, a Gram-positive bacterium, is an agent of food poisoning. B. cereus is closely related to Bacillus anthracis, a deadly pathogen for humans, and Bacillus thuringenesis, an insect pathogen. Due to the growing prevalence of antibiotic resistance in bacteria, alternative antimicrobials are needed. One such alternative is peptidoglycan hydrolase enzymes, which can lyse Gram-positive bacteria when exposed externally. A bioinformatic search for bacteriolytic enzymes led to the discovery of a gene encoding an endolysin-like endopeptidase, LysBC17, which was then cloned from the genome of B. cereus strain Bc17. This gene is also present in the B. cereus ATCC 14579 genome. The gene for LysBC17 encodes a protein of 281 amino acids. Recombinant LysBC17 was expressed and purified from E. coli. Optimal lytic activity against B. cereus occurred between pH 7.0 and 8.0, and in the absence of NaCl. The LysBC17 enzyme had lytic activity against strains of B. cereus, B. anthracis, and other Bacillus species. Full article

Background: Azaspiracids (AZAs) are marine toxins that are produced by Azadinium and Amphidoma dinoflagellates that can contaminate edible shellfish inducing a foodborne poisoning in humans, which is characterized by gastrointestinal symptoms. Among these, AZA1, -2, and -3 are regulated in the European Union, being the most important in terms of occurrence and toxicity. In vivo studies in mice showed that, in addition to gastrointestinal effects, AZA1 induces liver alterations that are visible as a swollen organ, with the presence of hepatocellular fat droplets and vacuoles. Hence, an in vitro study was carried out to investigate the effects of AZA1, -2, and -3 on liver cells, using human non-tumor IHH hepatocytes. Results: The exposure of IHH cells to AZA1, -2, or -3 (5 × 10⁻¹²–1 × 10⁻⁷ M) for 24 h did not affect the cell viability and proliferation (Sulforhodamine B assay and ³H-Thymidine incorporation assay), but they induced a significant concentration-dependent increase of mitochondrial dehydrogenases activity (MTT reduction assay). This effect depends on the activity of mitochondrial electron transport chain complex I and II, being counteracted by rotenone and tenoyl trifluoroacetone, respectively. Furthermore, AZAs-increased mitochondrial dehydrogenase activity was almost totally suppressed in the K⁺-, Cl⁻-, and Na⁺-free media and sensitive to the specific inhibitors of K_ATP and hERG potassium channels, Na⁺/K⁺, ATPase, and cystic fibrosis transmembrane conductance regulator (CFTR) chloride channels. Conclusions: These results suggest that AZA mitochondrial effects in hepatocytes derive from an imbalance of intracellular levels of K⁺ and, in particular, Cl⁻ ions, as demonstrated by the selective reduction of toxin effects by CFTR chloride channel inhibition. Full article