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1.
Theor Appl Genet ; 137(6): 118, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38709404

RESUMO

KEY MESSAGE: Through a map-based cloning approach, a gene coding for an R2R3-MYB transcription factor was identified as a causal gene for the I locus controlling the dominant white bulb color in onion. White bulb colors in onion (Allium cepa L.) are determined by either the C or I loci. The causal gene for the C locus was previously isolated, but the gene responsible for the I locus has not been identified yet. To identify candidate genes for the I locus, an approximately 7-Mb genomic DNA region harboring the I locus was obtained from onion and bunching onion (A. fistulosum) whole genome sequences using two tightly linked molecular markers. Within this interval, the AcMYB1 gene, known as a positive regulator of anthocyanin production, was identified. No polymorphic sequences were found between white and red AcMYB1 alleles in the 4,860-bp full-length genomic DNA sequences. However, a 4,838-bp LTR-retrotransposon was identified in the white allele, in the 79-bp upstream coding region from the stop codon. The insertion of this LTR-retrotransposon created a premature stop codon, resulting in the replacement of 26 amino acids with seven different residues. A molecular marker was developed based on the insertion of this LTR-retrotransposon to genotype the I locus. A perfect linkage between bulb color phenotypes and marker genotypes was observed among 5,303 individuals of segregating populations. The transcription of AcMYB1 appeared to be normal in both red and white onions, but the transcription of CHS-A, which encodes chalcone synthase and is involved in the first step of the anthocyanin biosynthesis pathway, was inactivated in the white onions. Taken together, an aberrant AcMYB1 protein produced from the mutant allele might be responsible for the dominant white bulb color in onions.


Assuntos
Mapeamento Cromossômico , Genes de Plantas , Cebolas , Pigmentação , Cebolas/genética , Pigmentação/genética , Alelos , Fenótipo , Marcadores Genéticos , Retroelementos/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Antocianinas/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Cor , Brancos
2.
Arch Microbiol ; 206(6): 262, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38753198

RESUMO

The employment of versatile bacterial strains for the efficient degradation of carcinogenic textile dyes is a sustainable technology of bioremediation for a neat, clean, and evergreen globe. The present study has explored the eco-friendly degradation of complex Reactive Green 12 azo dye to its non-toxic metabolites for safe disposal in an open environment. The bacterial degradation was performed with the variable concentrations (50, 100, 200, 400, and 500 mg/L) of Reactive Green 12 dye. The degradation and toxicity of the dye were validated by high-performance liquid chromatography, Fourier infrared spectroscopy analysis, and phytotoxicity and genotoxicity assay, respectively. The highest 97.8% decolorization was achieved within 12 h. Alternations in the peaks and retentions, thus, along with modifications in the functional groups and chemical bonds, confirmed the degradation of Reactive Green 12. The disappearance of a major peak at 1450 cm-1 corresponding to the -N=N- azo link validated the breaking of azo bonds and degradation of the parent dye. The 100% germination of Triticum aestivum seed and healthy growth of plants verified the lost toxicity of degraded dye. Moreover, the chromosomal aberration of Allium cepa root cell treatment also validated the removal of toxicity through bacterial degradation. Thereafter, for efficient degradation of textile dye, the bacterium is recommended for adaptation to the sustainable degradation of dye and wastewater for further application of degraded metabolites in crop irrigation for sustainable agriculture.


Assuntos
Biodegradação Ambiental , Corantes , Cebolas , Indústria Têxtil , Triticum , Corantes/metabolismo , Corantes/química , Corantes/toxicidade , Triticum/microbiologia , Cebolas/efeitos dos fármacos , Compostos Azo/metabolismo , Compostos Azo/toxicidade , Têxteis , Bactérias/metabolismo , Bactérias/efeitos dos fármacos , Bactérias/genética , Testes de Mutagenicidade
3.
J Environ Manage ; 359: 120988, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38701587

RESUMO

Microalgae demonstrate significant potential as a source of liquid-based biofuels. However, increasing biomass productivity in existing cultivation systems is a critical prerequisite for their successful integration into large-scale operations. Thus, the current work aimed to accelerate the growth of C. vulgaris via exogenous supplementation of biostimulant derived from onion peel waste. Under the optimal growth conditions, which entailed a biostimulant dosage of 37.5% v/v, a pH of 3, an air flow rate of 0.4 L/min, and a 2% v/v inoculum harvested during the mid-log phase, yielded a maximum biomass concentration of 1.865 g/L. Under the arbitrarily optimized parameters, a comparable growth pattern was evident in the upscaled cultivation of C. vulgaris, underscoring the potential commercial viability of the biostimulant. The biostimulant, characterized through gas chromatography-mass spectrometry (GC-MS) analysis, revealed a composition rich in polyphenolic and organo-sulphur compounds, notably including allyl trisulfide (28.13%), methyl allyl trisulfide (23.04%), and allyl disulfide (20.78%), showcasing potent antioxidant properties. Additionally, microalgae treated with the biostimulant consistently retained their lipid content at 18.44% without any significant reduction. Furthermore, a significant rise in saturated fatty acid (SFA) content was observed, with C16:0 and C18:1 dominating both bench-scale (44.08% and 14.01%) and upscaled (51.12% and 13.07%) microalgae cultures, in contrast to the control group where C18:2 was prevalent. Consequently, SFA contents reached 54.35% and 65.43% in bench-scale and upscaled samples respectively, compared to 33.73% in the control culture. These compositional characteristics align well with the requirements for producing high-quality crude biodiesel.


Assuntos
Biocombustíveis , Biomassa , Microalgas , Cebolas , Microalgas/crescimento & desenvolvimento , Cebolas/crescimento & desenvolvimento , Cromatografia Gasosa-Espectrometria de Massas
4.
ScientificWorldJournal ; 2024: 2795747, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38559755

RESUMO

Onion (Allium cepa L.) is the most important commercial vegetable crop widely grown throughout the world. It is also an important bulb crop in Ethiopia. However, its production and productivity are restricted by different factors, including biotic and abiotic stresses. This review investigates the potential impacts of spacing and varieties on onion yield and yield components in Ethiopia. Countries around the world are producing onion for its nutritional value, medicinal properties, minerals, proteins, and carbohydrates. In terms of production, onion ranks second only after tomatoes. The average onion yield in Ethiopia is estimated to be 8.8 tons/ha, while in the world, it is approximately 19.7 tons/ha. Inappropriate spacing and inadequate onion varieties are some of the limitations widely described for yield variation in Ethiopia. Thus, to control the size, shape, and yield of onion bulbs, spacing determination and variety improvement are some of the techniques currently employed in Ethiopia. Adama red, Bombay red, and red creole are some of the known varieties in the country, and the intrarow spacings for Adama red and Bombay red are reported to be 4 cm and 6 cm, respectively. Different spacing between onion plants affects how much they produce and other factors such as size and quality, depending on the variety. It is important to assess whether changing spacing makes sense from both a farming and economic standpoint, alongside considering other agricultural methods.


Assuntos
Agricultura , Cebolas , Etiópia
5.
BMC Plant Biol ; 24(1): 237, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38566021

RESUMO

BACKGROUND: Onions are economically and nutritionally important vegetable crops. Despite advances in technology and acreage, Indian onion growers face challenges in realizing their full productivity potential. This study examines the technical efficiency of onion growers, the factors influencing it, and the constraints faced by those adopting drip irrigation in the Ghod river basin of western Maharashtra. A sample of 480 farmers including those practicing drip irrigation and those not practicing it, was selected from Junnar, Shirur, Parner, and Shrigonda blocks of the basin. The primary data was collected through semi-structured interviews. Analytical tools such as the Cobb-Douglas production function (represents technological relationship between multiple inputs and the resulting output), a single-stage stochastic frontier model, the Tobit model, and descriptive statistics were used to assess the technical efficiency of onion production at the farm level. RESULTS: According to the maximum likelihood estimates of the stochastic frontier analysis, drip adopters exhibited a mean technical efficiency of 92%, while for non-adopters it was 65%. It indicates that the use of drip irrigation technology is associated with higher technical efficiency. The association of technical efficiency and socio-economic characters of households showed that education, extension contacts, social participation, and use of information sources had a positive influence on technical efficiency, while family size had a negative influence on the drip irrigation adopters. For non-drip adopters, significant positive effects were observed for landholding, extension contact, and information source use. The major constraints faced by drip system adopters included a lack of knowledge about the proper operating techniques for drip systems and the cost of maintenance. CONCLUSION: The differences with inputs associated with two irrigation methods showed that the response of inputs to increase onion yield is greater for farmers who use drip irrigation than for farmers who do not, and are a result of the large differences in the technical efficiencies. These inefficiencies and other limitations following the introduction of drip irrigation, such as lack of knowledge about the proper operations, need to be addressed through tailored training for farmers and further interventions.


Assuntos
Irrigação Agrícola , Cebolas , Irrigação Agrícola/métodos , Índia , Fazendas , Produtos Agrícolas
6.
Sci Rep ; 14(1): 8651, 2024 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622233

RESUMO

In this study, the multifaceted toxicity induced by high doses of the essential trace element molybdenum in Allium cepa L. was investigated. Germination, root elongation, weight gain, mitotic index (MI), micronucleus (MN), chromosomal abnormalities (CAs), Comet assay, malondialdehyde (MDA), proline, superoxide dismutase (SOD), catalase (CAT) and anatomical parameters were used as biomarkers of toxicity. In addition, detailed correlation and PCA analyzes were performed for all parameters discussed. On the other hand, this study focused on the development of a two hidden layer deep neural network (DNN) using Matlab. Four experimental groups were designed: control group bulbs were germinated in tap water and application group bulbs were germinated with 1000, 2000 and 4000 mg/L doses of molybdenum for 72 h. After germination, root tips were collected and prepared for analysis. As a result, molybdenum exposure caused a dose-dependent decrease (p < 0.05) in the investigated physiological parameter values, and an increase (p < 0.05) in the cytogenetic (except MI) and biochemical parameter values. Molybdenum exposure induced different types of CAs and various anatomical damages in root meristem cells. Comet assay results showed that the severity of DNA damage increased depending on the increasing molybdenum dose. Detailed correlation and PCA analysis results determined significant positive and negative interactions between the investigated parameters and confirmed the relationships of these parameters with molybdenum doses. It has been found that the DNN model is in close agreement with the actual data showing the accuracy of the predictions. MAE, MAPE, RMSE and R2 were used to evaluate the effectiveness of the DNN model. Collective analysis of these metrics showed that the DNN model performed well. As a result, it has been determined once again that high doses of molybdenum cause multiple toxicity in A. cepa and the Allium test is a reliable universal test for determining this toxicity. Therefore, periodic measurement of molybdenum levels in agricultural soils should be the first priority in preventing molybdenum toxicity.


Assuntos
Allium , Molibdênio/toxicidade , Raízes de Plantas , Meristema , Cebolas/fisiologia , Aberrações Cromossômicas
7.
Environ Sci Pollut Res Int ; 31(21): 30902-30913, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38622416

RESUMO

Among the compounds present in necro-leachate, a liquid released during the process of decomposition of the human body, are the biogenic amines cadaverine and putrescine. Although some studies on necro-leachate have indicated a potential ecotoxicological and public health risk associated with it, the research on this type of contamination is still rather limited. This study presents information about the phytotoxic and cytogenotoxic potential of cadaverine and putrescine, evaluated separately and within a mixture. Phytotoxicity was evaluated through a germination test, the initial growth of seedlings with Lactuca sativa, and cytogenotoxicity through chromosomal aberration and micronucleus tests with Allium cepa. The L. sativa results showed a phytotoxic effect for the evaluated amines, by reducing root (> 90%) and hypocotyl (> 80%) elongation. The co-exposure of cadaverine and putrescine potentiated cytogenotoxic activity by aneugenic action in the meristematic cells of A. cepa. From this result, it is possible to infer the eco-toxicogenic potential of cadaverine and putrescine. This study not only highlights the importance of the phytotoxic and cytogenotoxic effects of these amines but also emphasizes the urgent need for further investigation into contamination originating from cemetery environments. By evaluating the risks associated with necro-leachate, this research is aimed at informing global efforts to protect ecological and public health.


Assuntos
Aminas Biogênicas , Cadaverina , Putrescina , Aminas Biogênicas/toxicidade , Lactuca/efeitos dos fármacos , Cebolas/efeitos dos fármacos , Germinação/efeitos dos fármacos
8.
Spectrochim Acta A Mol Biomol Spectrosc ; 316: 124286, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-38663135

RESUMO

A simple single step one pot multicomponent reaction was performed to synthesize N-(tert-butyl)-2-(furan-2-yl)imidazo[1,2-a]pyridine-3-amine (TBFIPA). The synthesized TBFIPA was subjected to library of cations to study its ability for selective and sensitive detection of specific metal ions. Selective detection of chromium ions by TBFIPA were found from the significant hypsochromic shift (335 nm â†’ 285 nm) in the UV-Visible spectra. The fluorescent TBFIPA displays complete quenching of fluorescence under UV lamp (365 nm) only in the presence of chromium without the interference of common metal ions. Binding constant (ka) obtained from Benesi-Hildebrand plot is 0.21 × 105 M-1, limit of detection (LOD) and limit of quantification (LOQ) of TBFIPA toward Cr3+ ions are 4.70 × 10-7 M and 1.56 × 10-7 M, respectively. The mechanism proposed during complex formation were supported by stoichiometric Job continuous variation plot, 1H NMR titration and ESI-MS spectroscopic data. All the experimental confirmation for complex formation were corroborated with theoretical DFT studies optimized using RB3LYP/6-31G(d) basis set. The selectivity and sensitivity of TBFIPA toward Cr3+ ions are found suitable to design a user-friendly silica based portable test kit. Alongside, TBFIPA was successfully utilized for imaging onion epidermal cells. Furthermore, the results obtained for biological, environmental, and industrial samples provided solid evidence to estimate chromium ions using TBFIPA in these real samples.


Assuntos
Cromo , Corantes Fluorescentes , Limite de Detecção , Espectrometria de Fluorescência , Cromo/análise , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Espectrometria de Fluorescência/métodos , Cebolas/química , Piridinas/química , Espectrofotometria Ultravioleta , Íons/análise
9.
Sci Rep ; 14(1): 9374, 2024 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-38653777

RESUMO

Colletotrichum is an important plant pathogenic fungi that causes anthracnose/-twister disease in onion. This disease was prevalent in the monsoon season from August to November months and the symptoms were observed in most of the fields. This study aimed to investigate the pathogenicity and cumulative effect, if any of Colletotrichum gloeosporioides and Fusarium acutatum. The pot experiment was laid out to identify the cause responsible for inciting anthracnose-twister disease, whether the Colletotrichum or Fusarium or both, or the interaction of pathogens and GA3. The results of the pathogenicity test confirmed that C. gloeosporioides and F. acutatum are both pathogenic. C. gloeosporioides caused twisting symptoms independently, while F.acutatum independently caused only neck elongation. The independent application of GA3 did not produce any symptoms, however, increased the plant height. The combined treatment of C. gloeosporioides and F. acutatum caused twisting, which enhanced upon interaction with GA3 application giving synergistic effect. The acervuli were found in lesions infected with C. gloeosporioides after 8 days of inoculation on the neck and leaf blades. Symptoms were not observed in untreated control plants. Koch's postulates were confirmed by reisolating the same pathogens from the infected plants.


Assuntos
Colletotrichum , Fusarium , Cebolas , Doenças das Plantas , Colletotrichum/patogenicidade , Fusarium/patogenicidade , Doenças das Plantas/microbiologia , Cebolas/microbiologia
10.
Sheng Wu Gong Cheng Xue Bao ; 40(4): 1076-1088, 2024 Apr 25.
Artigo em Chinês | MEDLINE | ID: mdl-38658150

RESUMO

Flavin-containing monooxygenase (FMO) is the key enzyme in the biosynthesis pathway of CSOs with sulfur oxidation. In order to explore the molecular regulatory mechanism of FMO in the synthesis of onion CSOs, based on transcriptome database and phylogenetic analysis, one AcFMO gene that may be involved in alliin synthesis was obtained, the AcFMO had a cDNA of 1 374 bp and encoded 457 amino acids, which was evolutionarily closest to the AsFMO of garlic. Real-time fluorescence quantitative polymerase chain reaction (qRT-PCR) indicated that AcFMO was the highest in the flowers and the lowest in the leaf sheaths. The results of subcellular localization showed that the AcFMO gene product was widely distributed throughout the cell A yeast expression vector was constructed, and the AcFMO gene was ecotopically overexpressed in yeast to further study the enzyme function in vitro and could catalyze the synthesis of alliin by S-allyl-l-cysteine. In summary, the cloning and functional identification of AcFMO have important reference value for understanding the biosynthesis of CSOs in onions.


Assuntos
Clonagem Molecular , Cisteína/análogos & derivados , Cebolas , Cebolas/genética , Cebolas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Cisteína/biossíntese , Cisteína/metabolismo , Oxigenases/genética , Oxigenases/metabolismo , Sequência de Aminoácidos , Filogenia , Dissulfetos/metabolismo , Dados de Sequência Molecular , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo
11.
Pharm Biol ; 62(1): 326-340, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38584568

RESUMO

CONTEXT: Asthma presents a global health challenge. The main pharmacotherapy is synthetic chemicals and biological-based drugs that are costly, and have significant side effects. In contrast, use of natural products, such as onion (Allium cepa L., Amaryllidaceae) in the treatment of airway diseases has increased world-wide because of their perceived efficacy and little safety concerns. However, their pharmacological actions remain largely uncharacterized. OBJECTIVE: We investigated whether onion bulb extract (OBE) can (1) reverse established asthma phenotype (therapeutic treatment) and/or (2) prevent the development of the asthma phenotype, if given before the immunization process (preventative treatment). MATERIALS AND METHODS: Six groups of male Balb/c mice were established for the therapeutic (21 days) and five groups for the preventative (19 days) treatment protocols; including PBS and house dust mite (HDM)-challenged mice treated with vehicle or OBE (30, 60, and 100 mg/kg/i.p.). Airways inflammation was determined using cytology, histology, immunofluorescence, Western blot, and serum IgE. RESULTS: Therapeutic (60 mg/kg/i.p.) and preventative (100 mg/kg/i.p.) OBE treatment resulted in down-regulation of HDM-induced airway cellular influx, histopathological changes and the increase in expression of pro-inflammatory signaling pathway EGFR, ERK1/2, AKT, pro-inflammatory cytokines and serum IgE. DISCUSSION AND CONCLUSION: Our data show that OBE is an effective anti-inflammatory agent with both therapeutic and preventative anti-asthma effects. These findings imply that onion/OBE may be used as an adjunct therapeutic agent in established asthma and/or to prevent development of allergic asthma. However, further studies to identify the active constituents, and demonstrate proof-of-concept in humans are needed.


Assuntos
Asma , Cebolas , Humanos , Masculino , Animais , Camundongos , Modelos Animais de Doenças , Asma/tratamento farmacológico , Asma/prevenção & controle , Inflamação/tratamento farmacológico , Inflamação/prevenção & controle , Inflamação/metabolismo , Citocinas/metabolismo , Pyroglyphidae/metabolismo , Imunoglobulina E , Camundongos Endogâmicos BALB C , Pulmão
12.
Environ Pollut ; 349: 123990, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38631447

RESUMO

An indigenous bacterium Pseudomonas sp. EN-4 had been reported earlier for its ability to co-metabolise 4-bromophenol (4-BP), in presence of phenol (100 mg/L) as co-substrate. The present study was undertaken to validate the efficacy of biotransformation by comparing the toxicity profiles of untreated and EN-4 transformed samples of 4-BP, using both plant and animal model. The toxicity studies in Allium cepa (A. cepa) indicated to lowering of mitotic index (MI) from 12.77% (water) to 3.33% in A. cepa bulbs exposed to 4-BP + phenol, which reflects the cytotoxic nature of these compounds. However, the MI value significantly improves to 11.36% in its biologically treated counterpart, indicating normal cell growth. This was further supported by significant reduction in chromosomal aberrations in A. cepa root cells exposed to biologically treated samples of 4-BP as compared to untreated controls. The oxidative stress assessed by comparing the activity profiles of different marker enzymes showed that the activities of superoxide dismutase (SOD), ascorbate peroxidase (APX) and guaiacol peroxidase (GPX) were reduced by 56%, 72%, and 37% respectively, in EN-4 transformed samples of 4-BP + phenol compared to its untreated counterpart. Similar trends were evident in the comet assay of fish (Channa punctatus) blood cells exposed to untreated and biologically treated samples of 4-BP. The comparative studies showed significant reduction in tail length (72.70%) and % tail intensity (56.15%) in fish blood cells exposed to EN-4 treated 4-BP + phenol, compared to its untreated counterpart. The soil microcosm studies validated the competency of the EN-4 cells to establish and transform 4-BP in soil polluted with 4-BP (20 mg/kg) and 4-BP + phenol (20 + 100 mg/kg). The isolate EN-4 achieved 98.08% transformation of 4-BP in non-sterile microcosm supplemented with phenol, indicating to potential of EN-4 cells to establish along with indigenous microflora.


Assuntos
Cebolas , Fenóis , Pseudomonas , Fenóis/toxicidade , Fenóis/metabolismo , Pseudomonas/metabolismo , Animais , Cebolas/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Biodegradação Ambiental , Poluentes do Solo/toxicidade , Biotransformação , Superóxido Dismutase/metabolismo
13.
Nutrients ; 16(8)2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38674916

RESUMO

A sedentary lifestyle associated with unregulated diets rich in high-calorie foods have contributed to the great prevalence of metabolic dysfunction-associated steatotic liver disease (MASLD) latterly, with up to 60% in the high-risk population and 25% in the general population. The absence of specific pharmacological strategies for this syndrome represents one of the major problems in the management of MASLD patients. Lifestyle interventions and adherence to a healthy diet are the main cornerstones of current therapies. The identification of nutraceuticals useful in the treatment of MASLD appears to be one of the most promising strategies for the development of new effective and safe treatments for this disease. The onion, one of the most widely studied foods in the field of nutraceuticals, serves as an inexhaustible reservoir of potent compounds with various beneficial effects. The following preliminary study analyzes, mediating in silico studies, the iteration of a library of typical onion compounds with 3-hydroxy-3-methylglutaryl-coenzyme A reductase, liver receptors X α and ß, as well as peroxisome proliferator-activated receptors α and γ. In this study, for the first time promising smart molecules from the onion that could have a beneficial action in MASLD patients were identified.


Assuntos
Simulação de Acoplamento Molecular , Cebolas , Polifenóis , Cebolas/química , Polifenóis/farmacologia , Humanos , Ligantes , Suplementos Nutricionais , Hidroximetilglutaril-CoA Redutases/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo
14.
Int J Biol Macromol ; 266(Pt 1): 131209, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38565364

RESUMO

Mercury ion (Hg2+) is one of harmful heavy metal ions that can accumulate inside the human organism and cause some health problems. In the article, a highly effective fluorescent probe named EC-T-PCBM was prepared by grafting flavonol derivatives onto ethyl cellulose for the specific recognition of Hg2+. EC-T-PCBM exhibited a remarkable fluorescence light-up response toward Hg2+ with excellent sensitivity. EC-T-PCBM possessed several prominent sensing properties for Hg2+, such as low detection limit (43.9 nM), short response time (5 min), and wide detection pH range (6-9). The response mechanism of EC-T-PCBM to Hg2+ has been verified through 1H NMR titration and DFT computation. Additionally, EC-T-PCBM not only can be used for accurately determining trace amount of Hg2+ in actual environmental water samples, but also can serve as a portable and rapid device by loading it on test strips for sensitive and selective visualization of Hg2+. More importantly, the confocal fluorescence imaging of onion cells suggested the favorable cell membrane permeability of EC-T-PCBM and its prominent ability to continuously monitor the enrichment from Hg2+ within fresh plant tissues.


Assuntos
Celulose , Flavonóis , Corantes Fluorescentes , Mercúrio , Mercúrio/análise , Celulose/química , Celulose/análogos & derivados , Corantes Fluorescentes/química , Flavonóis/química , Flavonóis/análise , Espectrometria de Fluorescência/métodos , Limite de Detecção , Concentração de Íons de Hidrogênio , Poluentes Químicos da Água/análise , Cebolas/química , Imagem Óptica/métodos
15.
Antiviral Res ; 225: 105856, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38447646

RESUMO

Four years after its outbreak, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) remains a global challenge for human health. At its surface, SARS-CoV-2 features numerous extensively glycosylated spike proteins. This glycan coat supports virion docking and entry into host cells and at the same time renders the virus less susceptible to neutralizing antibodies. Given the high genetic plasticity of SARS-CoV-2 and the rapid emergence of immune escape variants, targeting the glycan shield by carbohydrate-binding agents emerges as a promising strategy. However, the potential of carbohydrate-targeting reagents as viral inhibitors remains underexplored. Here, we tested seven plant-derived carbohydrate-binding proteins, called lectins, and one crude plant extract for their antiviral activity against SARS-CoV-2 in two types of human lung cells: A549 cells ectopically expressing the ACE2 receptor and Calu-3 cells. We identified three lectins and an Allium porrum (leek) extract inhibiting SARS-CoV-2 infection in both cell systems with selectivity indices (SI) ranging between >2 and >299. Amongst these, the lectin Concanavalin A (Con A) exerted the most potent and broad activity against a panel of SARS-CoV-2 variants. We used multiplex super-resolution microscopy to address lectin interactions with SARS-CoV-2 and its host cells. Notably, we discovered that Con A not only binds to SARS-CoV-2 virions and their host cells, but also causes SARS-CoV-2 aggregation. Thus, Con A exerts a dual mode-of-action comprising both, antiviral and virucidal, mechanisms. These results establish Con A and other plant lectins as candidates for COVID-19 prevention and basis for further drug development.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , Cebolas/metabolismo , Concanavalina A/metabolismo , Lectinas/metabolismo , Polissacarídeos , Antivirais/farmacologia , Extratos Vegetais , Glicoproteína da Espícula de Coronavírus
16.
J Bacteriol ; 206(4): e0006924, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38488356

RESUMO

Bacteria are capable of withstanding large changes in osmolality and cytoplasmic pH, unlike eukaryotes that tightly regulate their pH and cellular composition. Previous studies on the bacterial acid stress response described a rapid, brief acidification, followed by immediate recovery. More recent experiments with better pH probes have imaged single living cells, and we now appreciate that following acid stress, bacteria maintain an acidic cytoplasm for as long as the stress remains. This acidification enables pathogens to sense a host environment and turn on their virulence programs, for example, enabling survival and replication within acidic vacuoles. Single-cell analysis identified an intracellular pH threshold of ~6.5. Acid stress reduces the internal pH below this threshold, triggering the assembly of a type III secretion system in Salmonella and the secretion of virulence factors in the host. These pathways are significant because preventing intracellular acidification of Salmonella renders it avirulent, suggesting that acid stress pathways represent a potential therapeutic target. Although we refer to the acid stress response as singular, it is actually a complex response that involves numerous two-component signaling systems, several amino acid decarboxylation systems, as well as cellular buffering systems and electron transport chain components, among others. In a recent paper in the Journal of Bacteriology, M. G. Gorelik, H. Yakhnin, A. Pannuri, A. C. Walker, C. Pourciau, D. Czyz, T. Romeo, and P. Babitzke (J Bacteriol 206:e00354-23, 2024, https://doi.org/10.1128/jb.00354-23) describe a new connection linking the carbon storage regulator CsrA to the acid stress response, highlighting new additional layers of complexity.


Assuntos
Proteínas de Escherichia coli , Escherichia coli , Escherichia coli/metabolismo , Cebolas/metabolismo , Proteínas de Bactérias/metabolismo , Citoplasma/metabolismo , Vacúolos/metabolismo , Salmonella/metabolismo , Ácidos/metabolismo , Proteínas Repressoras/metabolismo , Proteínas de Ligação a RNA/metabolismo , Proteínas de Escherichia coli/metabolismo
17.
J Food Sci ; 89(4): 2025-2039, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38465674

RESUMO

Microbial contamination of dehydrated onion products is a challenge to the industry. The study focused on opting for a suitable drying condition for minced onion and exploring the decontamination efficacy of pulsed light (PL) treatment conditions for the dehydrated product. The minced onions were hot air dried at 55-75°C for 280 min. The drying condition selected was 195 min at 75°C with a final water activity of 0.5 and moisture content of 7% (wet basis [w.b.]). The weight losses, browning indexes (BI), shrinkage volumes (%), and thiosulfinate content were considered. The dehydrated product was exposed to PL treatment corresponding to an effective fluence range of 0.007-0.731 J/cm2. A fluence of 0.444 J/cm2 (1.8 kV for 150 s) achieved 5.00, 3.14, 2.96, and 2.98 log reduction in total plate count, yeast and mold count, Bacillus cereus 10876, and Escherichia coli ATCC 43888, respectively. The PL-treated sample (0.444 J/cm2) produced a microbially safe product with no significant difference in the moisture contents (%w.b.) and water activity (aw) from the untreated dehydrated sample. Further, a 30.9% increase in the BI and a 4.25% depletion in thiosulfinate content were observed after PL treatment. An optimum drying combination (75°C for 195 min) of minced onion followed by decontamination using pulsed light treatment at 0.444 J/cm2 fluence satisfies the microbial safety and quality. PRACTICAL APPLICATION: Dehydrated minced onion can be used for dishes requiring low water content and short cooking time. It is helpful during shortages, high price fluctuations, and famines.


Assuntos
Escherichia coli O157 , Cebolas , Microbiologia de Alimentos , Contagem de Colônia Microbiana , Descontaminação , Desidratação , Água/farmacologia , Luz
18.
Int J Biol Macromol ; 264(Pt 1): 130537, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38432275

RESUMO

This study aimed to investigate the structural characteristics, in vivo antiatherosclerosis activity, and in vitro myocardial injury protection effects of polysaccharides from Allium macrostemon Bunge and Allium chinense G. Don. Thus, crude polysaccharides of Allium macrostemon Bunge and Allium chinense G. Don significantly reduced serum lipid levels, improved cardiac myocyte morphology and arrangement, and relieved the development of myocardial fibrosis. Meanwhile, the lesion areas of the aorta and aortic valve had evident visual improvements. Furthermore, two main novel purified polysaccharides, namely, AMB-1 and ACGD-1, were isolated and characterized from crude Allium macrostemon Bunge and Allium chinense G. Don fractions, respectively. The purified polysaccharides mainly consisted of fructose and glucose and had molecular weights of 25.22 and 19.53 kDa, respectively. In addition, Fourier transform infrared spectroscopy, methylation, and nuclear magnetic resonance data revealed the primary structures of the AMB1 (or ACGD1) backbone with branched side chains. Scanning electron microscope analysis showed that the purified polysaccharides were both piled together in a lamellar or clastic form with a smooth surface along with linear or irregular bulges. Moreover, the purified polysaccharides both showed nontoxicity on H9c2 cells and effectively dropped hypoxia/reoxygenation-induced apoptosis by the BCL-2/BAX pathway. Overall, the characterization of the structural properties and in vivo and in vitro myocardial injury protection effects of Allium macrostemon Bunge and Allium chinense G. Don polysaccharides enriched our understanding of their nutritional and medicinal values. To the best of our knowledge, this is the first study on the structural characteristics and bioactivities of Allium chinense G. Don polysaccharides.


Assuntos
Cebolinha-Francesa , Cebolas , Polissacarídeos , Espectroscopia de Ressonância Magnética , Polissacarídeos/farmacologia
19.
Sci Rep ; 14(1): 6076, 2024 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-38480751

RESUMO

When onions are improperly stored, a post-harvest disease known as black mold of onion bulbs can result in considerable economic losses. Aspergillus section Nigri, one of many species, has been implicated in the development of black mold. In the present study, rot onion bulbs were collected from markets in Qena, Egypt. Thirteen Aspergillus section Nigri isolates were obtained and identified by morphological and molecular characterization. The ochratoxins potential of isolated A. section Nigri was tested, and three isolates were producers at the range of 1.5-15 ppm. For the presence of pks gene, no amplification product was detected. Using the fungal growth inhibition test, the isolates of A. niger were inhibited by eco-friendly materials Cement and Zeolite. Cement exhibited maximum percentage growth inhibition against the tested isolates at 74.7-86.7%. The pathogenicity activity of the A. niger isolates was tested by inoculation of healthy onion bulbs, other onion bulbs covered with Cement and Zeolite before inoculation by A. niger was used. The two treatments significantly reduced bulbs rot disease of onion than untreated bulbs. Seven and nine isolates showed 0% rot on covered bulbs by Cement and Zeolite, respectively as compared with inoculated onions, which exhibited rot ranging from 55 to 80%. Using eco-friendly materials with efficiency against post-harvest bulbs rot of onion was evaluated in this study.


Assuntos
Ocratoxinas , Zeolitas , Cebolas/microbiologia , Aspergillus/genética , Egito
20.
Sci Rep ; 14(1): 6034, 2024 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-38472199

RESUMO

While onion cultivars, irrigation and soil and crop management have been given much attention in Brazil to boost onion yields, nutrient management at field scale is still challenging due to large dosage uncertainty. Our objective was to develop an accurate feature-based fertilization model for onion crops. We assembled climatic, edaphic, and managerial features as well as tissue tests into a database of 1182 observations from multi-environment fertilizer trials conducted during 13 years in southern Brazil. The complexity of onion cropping systems was captured by machine learning (ML) methods. The RReliefF ranking algorithm showed that the split-N dosage and soil tests for micronutrients and S were the most relevant features to predict bulb yield. The decision-tree random forest and extreme gradient boosting models were accurate to predict bulb yield from the relevant predictors (R2 > 90%). As shown by the gain ratio, foliar nutrient standards for nutritionally balanced and high-yielding specimens producing > 50 Mg bulb ha-1 set apart by the ML classification models differed among cultivars. Cultivar × environment interactions support documenting local nutrient diagnosis. The split-N dosage was the most relevant controllable feature to run future universality tests set to assess models' ability to generalize to growers' fields.


Assuntos
Cebolas , Solo , Nutrientes , Aprendizado de Máquina , Algoritmos
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