Publications by authors named "Sionov E"

Food and agricultural commodities endure consistent contamination by mycotoxins, low molecular weight fungal metabolites, which pose severe health implications to humans together with staggering economic losses. Herein, a ratiometric aptasensor was constructed using silver-coated porous silicon (Ag-pSi) used as an efficient surface-enhanced Raman scattering (SERS) substrate. The bioassay included direct detection of fumonisin B (FB), an abundant and widespread contaminant, by a specific aptamer sequence immobilized on the porous transducer.

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Numerous SERS based platforms have been designed to address the emerging need for detecting fungal metabolite contamination in foodstuffs, and specifically the Group 1 carcinogen aflatoxin B1. Herein, 4-aminothiophenol modified silver-coated porous silicon was used as the SERS substrate. Two ratiometric responses were individually assessed upon direct target capture using specific aptamers or antibodies.

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is a Mediterranean shrub cultivated in Israel for traditional, ceremonial use only, with more than 98 % of the crop biomass, equivalent to 26-27 tons per ha per annum, considered agricultural waste. Therefore, potentially profitable use for this excess is being highly sought. As is also known for its unique terpene and terpenoid content, this work evaluated the impact of essential oil (EO) extracted from several cultivars on storage insects, nematodes, fungi, and pathogens.

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Ypt GTPases are the largest subfamily of small GTPases involved in membrane transport. Here, a PeYpt7 gene deletion mutant of P. expansum was constructed.

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This work addresses the challenge of delivering bioactive molecules by designing biocompatible nanogel particles (NGPs) utilizing rationally modified nature-sourced building blocks: capryl-oligochitosan and oxidized inosine. Capryl substituents endowed the resultant NGPs with membrane-penetration capabilities, while purine-containing inosine allowed H-bond/π-π/π-cation interactions. The prepared NGPs were complexed with carboxyfluorescein-labeled single-stranded oligonucleotide (FAM-oligo) and DsRed-encoding plasmid DNA.

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Epigenetic modification of chromosome structure has increasingly been associated with alterations in secondary metabolism and sporulation defects in filamentous fungal pathogens. Recently, the epigenetic reader protein SntB was shown to govern virulence, spore production and mycotoxin synthesis in the fruit pathogen Penicillium expansum. Through immunoprecipitation-coupled mass spectrometry, we found that SntB is a member of a protein complex with KdmB, a histone demethylase and the essential protein RpdA, a histone deacetylase.

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Aspergillus flavus is a mycotoxigenic fungus that contaminates many important agricultural crops with aflatoxin B1, the most toxic and carcinogenic natural compound. This fungus is also the second leading cause of human invasive aspergillosis, after Aspergillus fumigatus, a disease that is particularly prevalent in immunocompromised individuals. Azole drugs are considered the most effective compounds in controlling Aspergillus infections both in clinical and agricultural settings.

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is a key gene for ergosterol biosynthesis in filamentous fungi, but its function in remains unknown. Our results showed that contains three genes, including , and . The expression levels of the three genes showed differences in the wild-type (WT) strain, and the expression level of was the highest, followed by .

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Herein, a label-free sensing platform was designed for accurate, rapid and selective detection of aflatoxin B1 (AFB1), a potent mutagenic and carcinogenic substance in food and feedstuff. Minute AFB1 residues were assessed by competitive immunoassay facilitated on porous silicon Fabry-Pérot interferometer. The immunocomplex formation was biochemically amplified by enzymatic reaction products infiltrating the porous void and alternating the reflectivity spectra in correlation to the AFB1 content.

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is a necrotrophic pathogen, which actively kills host cells and obtains nutrients from dead cells to achieve infection. However, few reports have elucidated the differential levels of carbon and nitrogen sources over increasing distances of the leading edge in fungal colonized fruit tissues during colonization. Our results showed that the highest consumption of sucrose and fructose, as well as the accumulation of glucose, were found in the decayed region of -colonized 'Delicious' apple fruit compared with the healthy region at the leading edge and the healthy region 6 mm away from the leading edge.

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Objective: In the present study, we aimed to investigate the presence of fungi that may affect human health in sand and water on Israeli Mediterranean Sea coast beaches.

Methods: The study included screening of the sand and water of six urban beaches from north to south on the Israeli Mediterranean coast. Sand samples were extracted with water, and the water wash was cultured and quantitated.

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A study was conducted on six animal feed centers in Israel where fungal and mycotoxin presence was examined in maize and wheat silages. Fumonisin mycotoxins FB and FB were present in every maize silage sample analyzed. Interestingly, no correlation was found between the occurrence of specific mycotoxins and the presence of the fungal species that might produce them in maize and wheat silages.

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pH is one of the important environmental factors that affect the growth, development and pathogenicity of postharvest pathogen. The transcription factor PacC dominates the pH signal pathway. PacC in Trichothecium roseum showed three typical conserved zinc finger domains and closest homology to Fusarium graminearum.

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Wheat grains are colonized by complex microbial communities that have the potential to affect seed quality and susceptibility to disease. Some of the beneficial microbes in these communities have been shown to protect plants against pathogens through antagonism. We evaluated the role of the microbiome in seed health: in particular, against mycotoxin-producing fungi.

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The occurrence of reactive oxygen species (ROS) during the colonization of necrotrophic pathogens attacking fruit is critical during the attack, but its importance in remains unclear. This study aimed to determine the regulatory effects of NADPH oxidase (Nox) genes on the growth and pathogenicity of in apple fruits. Deletion mutants of Δ, Δ, and Δ genes were constructed to determine the contribution to the colonization process.

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Patulin (PAT) and citrinin (CTN) are the most common mycotoxins produced by and species and are often associated with fruits and fruit by-products. Hence, simple and reliable methods for monitoring these toxins in foodstuffs are required for regular quality assessment. In this study, we aimed to establish a cost-effective method for detection and quantification of PAT and CTN in pome fruits, such as apples and pears, using high-performance liquid chromatography (HPLC) coupled with spectroscopic detectors without the need for any clean-up steps.

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is an important postharvest pathogen, belonging to an alkalizing group of pathogens secreting ammonia during fungal growth and colonization of apple fruits. Fungal pH modulation is usually considered a factor for improving fungal gene expression, contributing to its pathogenicity. However, the effects of inoculation with spore suspensions at increasing pH levels from pH 3 up to pH 7, on the reactive oxygen species (ROS) production and scavenging capability of the apple fruits, affecting host susceptibility, indicate that the pH regulation by the pathogens also affects host response and may contribute to colonization.

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The interplay between fungal pathogens and harvest crops is important in determining the extent of food losses following the storage and transport of crops to consumers. The specific factors modulating the activation of colonization are of key importance to determining the initiation of fungal colonization and host losses. It is clear nowadays from the wide number of transcription studies in colonized fruits that pathogenicity in postharvest produce is not only the result of activation of fungal pathogenicity factors but is significantly contributed to fruit maturity and ripening.

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is a strong and consistent ochratoxin A (OTA) producer and considered to be the main source of this toxic metabolite in grapes and grape products such as wine, grape juice and dried vine fruit. OTA is produced under certain growth conditions and its accumulation is affected by several environmental factors, such as growth phase, substrate, temperature, water activity and pH. In this study, we examined the impact of fruit host factors on regulation and accumulation of OTA in colonized grape berries, and assessed in vitro the impact of those factors on the transcriptional levels of the key genes and global regulators contributing to fungal colonization and mycotoxin synthesis.

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Aspergillus carbonarius is the major producer of ochratoxin A (OTA) among Aspergillus species, but the contribution of this secondary metabolite to fungal virulence has not been assessed. We characterized the functions and addressed the roles of three factors in the regulation of OTA synthesis and pathogenicity in A. carbonarius: LaeA, a transcriptional factor regulating the production of secondary metabolites; polyketide synthase, required for OTA biosynthesis; and glucose oxidase (GOX), regulating gluconic acid (GLA) accumulation and acidification of the host tissue during fungal growth.

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Background: Sand of sea harbour bacteria that may cause enteric and other infections in humans, and are controlled by regulatory measures. Data on fungi in sea sand are scarce. Thus, an international group of mycologists was formed to explore fungal flora in sand of various waterbodies.

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is one of the most harmful post-harvest pathogens of pomaceous fruits and the causal agent of blue rot disease. During infection, produces the toxic secondary metabolites patulin and citrinin that can impact virulence and, further, render the fruit inedible. Several studies have shown that epigenetic machinery controls synthesis of secondary metabolites in fungi.

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Pathogenic fungi must respond effectively to changes in environmental pH for successful host colonization, virulence and toxin production. is a mycotoxigenic pathogen with the ability to colonize many plant hosts and secrete ochratoxin A (OTA). In this study, we characterized the functions and addressed the role of PacC-mediated pH signaling in pathogenicity using designed gene knockout mutant.

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Fungal plant pathogens cause considerable losses in yield and quality of field crops worldwide. In addition, under specific environmental conditions, many fungi, including such as some and spp., are further able to produce mycotoxins while colonizing their host, which accumulate in human and animal tissues, posing a serious threat to consumer health.

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peppers are among the most popular horticultural crops produced and consumed worldwide. This study aimed to assess the occurrence of spoilage fungi responsible for post-harvest losses in the most common varieties of peppers collected from retail markets in Nigeria and Ghana. Forty fungal isolates belonging to 7 families, 8 genera, and 17 species were identified on the basis of morphology, culture characteristics, and DNA sequencing of the internal transcribed spacer (ITS) region.

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