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1.
Food Chem ; 370: 130851, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34530348

RESUMO

Health conscious and environmentally aware consumers are purchasing more organically produced foods. They prefer organic fruits and leafy vegetables as these are much less likely to have been exposed to contaminants such as pesticides. The detection of fraudulent activity in this area is difficult to undertake, because many chemical plant protection treatments degrade very quickly or can be washed off to remove evidence of their existence. It was found that when combining DART-MS with a compact, inexpensive and robust single quadrupole mass spectrometer, it was possible to differentiate organic from conventional leeks with 93.8% to 100% accuracy. ICP-MS results showed similar performance, with an ability to differentiate conventional from organic leeks with 92.5% to 98.1% accuracy. This study has paved the way for the certification of vegetables as being organically produced. The next step is to create data libraries to support the roll out of the methodologies described.


Assuntos
Cebolas , Verduras , Frutas , Espectrometria de Massas , Análise Espectral
2.
Food Chem ; 370: 131101, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34537427

RESUMO

Very little information is available with regards to the bioavailability of perchlorate in spinach or chard used in the production of baby foods commodities. In the present study, the uptake and accumulation of perchlorate were compared under two different treatments (T1: 1 and T2: 10 mg L-1 ClO4-). Our results indicate that spinach has a higher capacity to accumulate perchlorate than chard (p < 0.0185). Concentrations of perchlorate in leaves, stems and roots (leaves > stem > roots) all gradually increased (p < 0.0001) as vegetable growing and treatment (T2 > T1). No significant differences were found between the control and T1. The daily intake for perchlorate (control) is below the proposed international standard, however, it was exceeded in T1 and T2. The results suggested that perchlorate is actively accumulate in high concentrations in vegetables used in the production of baby food commodities and the exposure of perchlorate via the food consumption (baby foods) was evaluated as not safe.


Assuntos
Beta vulgaris , Percloratos , Contaminação de Alimentos/análise , Inocuidade dos Alimentos , Alimentos Infantis/análise , Percloratos/análise , Spinacia oleracea , Verduras
3.
J Sci Food Agric ; 102(1): 417-424, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34143904

RESUMO

BACKGROUND: Thiamethoxam is widely used to control pests in Chinese kale, popularly consumed leafy vegetables. The potential risk to the environment and human health has aroused much public concern. Therefore, it is important to investigate the degradation behavior, residue distribution and dietary risk assessment of thiamethoxam in Chinese kale. RESULTS: A sensitive analytical method for determination of thiamethoxam and its metabolite clothianidin residue in Chinese kale was established and validated through a quick, easy, cheap, effective, rugged, and safe (QuEChERS) technique with ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). The recoveries were 85.4-101.2% for thiamethoxam and 79.5-108.1% for clothianidin, with the relative standard deviations (RSDs) of 0.9-10.2% and 1.8-6.0%, respectively. For the dissipation kinetics, the data showed that thiamethoxam in Chinese kale was degraded with the half-lives of 4.1 to 4.5 days. In the terminal residue experiments, the residues of thiamethoxam were 0.017-0.357 mg kg-1 after application 2-3 times with a preharvest interval (PHI) of 7 days under the designed dosages. The chronic and acute dietary exposure assessment risk quotient (RQ) values of thiamethoxam in Chinese kale for different Chinese consumers were 0.08-0.19% and 0.05-0.12%, respectively, and those of clothianidin were 0.01-0.04% and 0.02-0.04%, respectively, all of the RQ values were lower than 100%. CONCLUSION: Thiamethoxam in Chinese kale was rapidly degraded following first-order kinetics models. The dietary risk of thiamethoxam and clothianidin through Chinese kale was negligible to consumers. The results from this study are important reference for Chinese governments to developing criteria for the safe and rational use of thiamethoxam, setting maximum residue levels (MRLs), monitoring the quality safety of agricultural products and protecting consumer health. © 2021 Society of Chemical Industry.


Assuntos
Brassica/química , Cromatografia Líquida/métodos , Guanidinas/metabolismo , Neonicotinoides/metabolismo , Resíduos de Praguicidas/química , Resíduos de Praguicidas/metabolismo , Espectrometria de Massas em Tandem/métodos , Tiametoxam/química , Tiametoxam/metabolismo , Tiazóis/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Brassica/metabolismo , Criança , Pré-Escolar , China , Exposição Dietética/efeitos adversos , Exposição Dietética/análise , Feminino , Contaminação de Alimentos/análise , Humanos , Cinética , Masculino , Pessoa de Meia-Idade , Medição de Risco , Verduras/química , Verduras/metabolismo , Adulto Jovem
4.
Int J Food Microbiol ; 361: 109458, 2022 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-34743052

RESUMO

Based on both new and previously utilized experimental data, the present study provides a comparative assessment of sensors and machine learning approaches for evaluating the microbiological spoilage of ready-to-eat leafy vegetables (baby spinach and rocket). Fourier-transform infrared (FTIR), near-infrared (NIR), visible (VIS) spectroscopy and multispectral imaging (MSI) were used. Two data partitioning approaches and two algorithms, namely partial least squares regression and support vector regression (SVR), were evaluated. Concerning baby spinach, when model testing was performed on samples randomly selected, the performance was better than or similar to the one attained when testing was performed based on dynamic temperatures data, depending on the applied analytical technology. The two applied algorithms yielded similar model performances for the majority of baby spinach cases. Regarding rocket, the random data partitioning approach performed considerably better results in almost all cases of sensor/algorithm combination. Furthermore, SVR algorithm resulted in considerably or slightly better model performances for the FTIR, VIS and NIR sensors, depending on the data partitioning approach. However, PLSR algorithm provided better models for the MSI sensor. Overall, the microbiological spoilage of baby spinach was better assessed by models derived mainly from the VIS sensor, while FTIR and MSI were more suitable in rocket. According to the findings of this study, a distinct sensor and computational analysis application is needed for each vegetable type, suggesting that there is not a single combination of analytical approach/algorithm that could be applied successfully in all food products and throughout the food supply chain.


Assuntos
Aprendizado de Máquina , Verduras , Análise dos Mínimos Quadrados , Espectroscopia de Infravermelho com Transformada de Fourier , Spinacia oleracea
5.
Food Chem ; 371: 131090, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34537617

RESUMO

A novel mixed matrix of MOF@COF hybrid was firstly formed by coating of hexahedral cage structure MOF with lightweight porous COF, and applied in dispersive solid-phase extraction of the phenoxy carboxylic acids (PCAs) from water and vegetable samples. Combined with liquid chromatography-tandem mass spectrometry, an excellent method with low limits of detection (0.69-1.79 ng·L-1/0.002-0.006 ng·g-1), good reproducibility (1.32%-7.02%/1.81%-6.71%), and excellent linearities (10-1000 ng·L-1, R ≥ 0.9955/0.04-50 ng·g-1, R ≥ 0.9966) was established. The adsorption mechanisms deduced that the π-π interaction, hydrophobic effects, hydrogen bond, and halogen bond may promote the excellent adsorption of the PCAs. Finally, the applicability of the method was verified by spiking four kinds of water and vegetable samples with PCAs, and satisfying recoveries were obtained (between 83.3% and 104.9%).


Assuntos
Ácidos Carboxílicos , Água , Ácidos Carboxílicos/análise , Cromatografia Líquida de Alta Pressão , Reprodutibilidade dos Testes , Extração em Fase Sólida , Verduras
6.
Food Chem ; 372: 131142, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34600193

RESUMO

To determine the glutathione (GSH) content in vegetables, an "on-off-on" fluorescence probe was developed by a synthesis of nitrogen and sulfur co-doped carbon dots (N,S-CDs) using the microwave pyrolysis considering citric acid and L-cysteine as precursors. The fluorescence of N,S-CDs was quenched by adding Cu2+ at a concentration of 20-200 µmol/L due to the inner filter effect. The quenched fluorescence of N,S-CDs@Cu2+ system was recovered by adding the GSH at a concentration of 10-150 µmol/L due to the sulfhydryl-metal compound mechanism. By observing the GSH concentrations measured by our N,S-CDs@Cu2+ system vs. a traditional fluorescent chelating method, the two measurements provided the GSH data with a good consistence by showing the RSD range of 1.86%-2.27%. This indicates the validation and novelty of our N,S-CDs@Cu2+ system as being a powerful fluorescent probe for effectively and efficiently determining the GSH in vegetables.


Assuntos
Glutationa , Pontos Quânticos , Carbono , Corantes Fluorescentes , Nitrogênio , Espectrometria de Fluorescência , Enxofre , Verduras
7.
Environ Pollut ; 292(Pt B): 118391, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34678394

RESUMO

To investigate tissue distribution, spatial difference, temperature variation, and potential health risks of PAEs in vegetables, celery was used as a model plant. Celery samples were collected from open fields and greenhouses from two provinces in China over four seasons. Celery tissues were analyzed for 16 PAE compounds by gas chromatography-tandem mass spectrometry. The total content of PAEs was 89.0-1130.3 µg kg-1 dry weight (dw) in stems and 155.0-2730.8 µg kg-1 dw in leaves. Concentrations of PAEs in celeries showed notable spatial differences (P < 0.05), and the levels in samples from open fields were lower than those in samples from plastic greenhouses. In celeries from greenhouses, higher PAE concentrations were observed for plants grown at high temperatures than in plants grown at low temperatures. Discrepancies in tissue distribution indicated different uptake pathways of PAE contaminants. Risk assessments to humans found that both carcinogenic risks and non-carcinogenic risks of PAEs via celery consumption were at an acceptable level. Further research should consider other exposure pathways of PAEs and pay special attention to reducing PAE contents in vegetables.


Assuntos
Apium , Ácidos Ftálicos , Poluentes do Solo , China , Dibutilftalato/análise , Exposição Dietética , Ésteres/análise , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Ácidos Ftálicos/análise , Solo , Poluentes do Solo/análise , Distribuição Tecidual , Verduras
8.
Biol Trace Elem Res ; 200(1): 426-436, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33644828

RESUMO

Vegetables are important contributors to a healthy diet, and their adequate daily intake can help prevent some of the major illnesses. The aim of the study was to examine the content of the major and trace elements in selected organically grown (OG) and conventionally grown (CG) vegetables (cabbage, kohlrabi, Brussels sprout, beetroot, carrot, potato, and onion), taken from city green markets. Multi-elemental analysis was carried out by inductively coupled plasma method with optical emission spectrometry (ICP-OES). Nutritional quality evaluation in comparison to nutritional reference values was done. In studied vegetables, Al, Ca, K, Fe (with the exception of organic kohlrabi), Mg, Na, P, S, and Zn were quantified in all samples, whereas As, Cd, Co, Hg, Se, and V were below the limit of detection for these elements. Macroelements and trace elements were found at higher concentrations in OG and CG vegetables, respectively. Differences in concentrations of studied elements between the same vegetable species produced in two agricultural systems were significant, except for beetroot (p ≤ 0.05). Principal component analysis and hierarchical cluster analysis results showed that the botanical origin had higher influence on sample differentiation than the agronomic practice, which was in accordance with the results obtained by Mann-Whitney U test. Good quality of both OG and CG vegetables in respect of nutritionally beneficial elements was observed.


Assuntos
Brassica , Oligoelementos , Avaliação Nutricional , Análise Espectral , Oligoelementos/análise , Verduras
9.
Food Chem ; 371: 131115, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34555710

RESUMO

The total antioxidant capacity (TAC) has become increasingly vital for evaluating antioxidant food quality in the field of healthcare. Herein, a convenient and sensitive method for TAC assay was proposed based on the absorbance difference of reaction systems between various antioxidants existed in food and Dex-FeMnzyme/oxTMB. Under the optimum condition, the limit of detection (LOD) of the colorimetric sensor was 1.17 µM with the linear concentration range from 1 µM to 30 µM. The analysis results demonstrated the excellent feasibility of practical application in fruit and vegetable food, which offered a new avenue for the establishment of colorimetric biosensors.


Assuntos
Antioxidantes , Frutas , Antioxidantes/análise , Colorimetria , Dextranos , Frutas/química , Oxirredução , Oxirredutases , Verduras
10.
Food Chem ; 371: 131126, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34583176

RESUMO

Organophosphates and carbamates pesticides are widely used to increase crop production globally causing a threat to human health and the environment. A variety of pesticides are applied during different stages of vegetable production. Therefore, monitoring the presence of pesticide residues in food and soil has great relevance to sensitive pesticide detection through distinct determination methods that are urgently required. Conventional techniques for the detection of pesticides have several limitations that can be overcome by the development of highly sensitive, fast, reliable and easy-to-use electrochemical biosensors. Herein, we describe the types of biosensors with the main focus on electrochemical biosensors fabricated for the detection of OPPs and carbamates pesticides. An overview of conventional techniques employed for pesticide detection is also discussed. This review aims to provide a glance of recently developed biosensors for some common pesticides like chlorpyrifos, malathion, parathion, paraoxon, and carbaryl which are present in food and environment samples.


Assuntos
Técnicas Biossensoriais , Paration , Resíduos de Praguicidas , Praguicidas , Humanos , Praguicidas/análise , Verduras
11.
Chemosphere ; 287(Pt 3): 132221, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34560492

RESUMO

Fruit and vegetables are one of the most consumed commodities globally, accounting for more than 42% of total food wastage. These vegetal foods can be consumed raw, processed, or taken as an addition to other food items. The continuous rise in population, in addition to technological advancements, has led to an imbalance in demand supply, resulting in increased food wastage globally. Although source reduction and recycling have shown promising results, more evaluations concerning economics and environmental impacts need to be given importance. The need of the hour lies in finding a possible method towards effective utilization for fruit and vegetable waste to generate value-added products which are more eco-friendly, cheaper, and sustainable. Thus, this article attempts to focus on the conventional and emerging opportunities of fruit and vegetable waste to generate value-added products. Conventional utilization, namely briquetting, waste to energy conversion, enzymatic degradation, and adsorption, as well as emerging opportunities in the areas of nutraceuticals, packaging, flavoring agents, and waste induced nanoparticles, have been emphasized. Additionally, recommendations and future perspectives towards better utilization of vegetal waste have been given importance. This review aims to narrow down the path towards evaluating the most techno-economic and efficient waste management technique for fruits and vegetable valorization, which can be promoted in the long term.


Assuntos
Verduras , Gerenciamento de Resíduos , Suplementos Nutricionais , Frutas , Reciclagem , Resíduos
12.
Sci Total Environ ; 805: 150441, 2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-34818792

RESUMO

Excess phosphorus (P) leached from high fertiliser input cropping systems in northern China is having detrimental effects on water quality. Before improved management can be directed at specific soils and cropping system types estimates of P leached loss apportionment and mitigation potentials across the main soil (fluvo-aquic soil, FAS; cinnamon soil, CS; black soil, BS) areas and cropping systems (protected vegetable fields, PVFs; open vegetable fields, OVFs; cereal fields, CFs) are needed. The present study designed and implemented conventional fertilisation and low input system trials at 75 sites inclusive of these main soils and cropping system types in northern China. At all sites, a uniform lysimeter design (to 0.9 m depth) enabled the collection and analysis of leachate samples from 7578 individual events between 2008 and 2018. In addition, site-specific static and dynamic activity data were recorded. Results showed that annual total phosphorus (TP) leached losses across the main soil areas and cropping systems were 4.99 × 106 kg in northern China. A major finding was PVFs contributed to 48.5% of the TP leached losses but only accounted for 5.7% of the total cropping areas. The CFs and OVFs accounted for 40.3% and 11.2% of the TP leached losses, respectively. Across northern China, the TP leached losses in PVFs and OVFs were greatest in FAS areas followed by CS and BS areas. The higher TP leached losses in FAS areas were closely correlated with greater P fertiliser inputs and irrigation practices. From a management perspective in PVFs and OVFs systems, a decrease of P inputs by 10-30% would not negatively affect yields while protecting water quality. The present study highlights the importance of decreasing P inputs in PVFs and OVFs and supporting soil P nutrient advocacy for farmers in China.


Assuntos
Fósforo , Solo , Agricultura , China , Fertilizantes/análise , Nitrogênio/análise , Fósforo/análise , Verduras , Qualidade da Água
13.
Food Chem ; 370: 131340, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34662791

RESUMO

The preliminary study examined the effectiveness of various vegetables for the stabilisation of omega-3 oil powders against oxidative deterioration. Purees made from different vegetables (mushroom, brussels sprouts, broccoli, cauliflower, snow peas, tomato, and garlic) were employed for preparation of vegetable-tuna oil emulsions, which were subsequently freeze-dried into powders. Oxipres® data showed that vegetable-tuna oil powders had longer induction periods than neat tuna oil. During accelerated oxidation storage (40 °C/4weeks), eicosapentaenoic and docosahexaenoic acids in the vegetable-tuna oil powders were protected against oxidation, and there were lower levels of headspace secondary and tertiary oxidation products. Whole vegetable purees were suitable protective matrices for omega-3 oils. Of the various vegetable purees examined for protective effects against omega-3 oxidation, mushroom, brussels sprouts, broccoli, and cauliflower were superior to snow peas, garlic and tomato. The antioxidant properties of phytonutrients inherent in various vegetables are likely contributors to protection of omega-3 oil powders against oxidation.


Assuntos
Ácidos Graxos Ômega-3 , Verduras , Oxirredução , Estresse Oxidativo , Pós
14.
Talanta ; 236: 122829, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34635219

RESUMO

The successful application of covalent organic frameworks (COFs) depends on not only their unique chemical structures but also their morphology, size, and architecture. Spherical COFs (SCOFs) are attracted special attention due to the superiority of spherical materials in many applications. However, the synthesis of uniform large-sized SCOFs remains a challenge. Herein, by carefully optimizing the synthesis of a heteropore COF, we find that solvent type and catalyst concentration play important roles in determining the morphology and size of COFs, and eventually achieve the controllable synthesis of large SCOFs with uniform sizes ranging from 200 µm to 5 mm. The obtained SCOFs keep the dual-pore feature of the heteropore COF and show good stability and high crystallinity. To exhibit the superior application potential of SCOFs, the SCOFs with a size range of 200-300 µm were demonstrated to be promising solid-phase extraction (SPE) fillers. As-prepared SCOFs-packed SPE column could effectively remove ≥99% phytochrome matrix from 6 different vegetable samples in 10 s, accompanied by 72.56-112.37% recoveries of 33 chemical hazards with different physicochemical properties, thus showing greatly promising application prospects in sample pretreatment of nontargeted food safety analysis. By utilizing acid/base-adjusted reversible color change, millimeter-sized SCOFs were developed as an easy-to-operate and reusable naked-eye indicator of acids.


Assuntos
Estruturas Metalorgânicas , Catálise , Extração em Fase Sólida , Verduras
15.
Food Chem ; 366: 130558, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34284184

RESUMO

Leafy vegetables like lettuce (Lactuca sativa L.) naturally have high nitrate content and the European Commission has set maximum level for nitrate in lettuce. Glycinebetaine is an organic osmolyte alleviating plant stress, but its role in leaf nitrate accumulation remains unknown. The uptake of glycinebetaine by lettuce roots, and its potential to regulate lettuce nitrate content and improve plant quality were investigated. Two hydroponic lettuce experiments were conducted with different glycinebetaine application rates (Exp1: 0, 1, 7.5, and 15 mM; Exp2: 0, 1 + 1 + 1, 1 + 10, and 4 mM). Plants were analyzed at varying time points. Root application resulted in glycinebetaine uptake and translocation to the leaves. Glycinebetaine concentrations > 7.5 mM reduced leaf nitrate up to 40% and increased leaf dry matter content. Glycinebetaine showed a positive effect on leaf mineral and amino acid composition. Thus, glycinebetaine could be a novel strategy to reduce the nitrate content in hydroponic lettuce.


Assuntos
Alface , Nitratos , Hidroponia , Nitratos/análise , Folhas de Planta/química , Verduras
16.
Food Chem ; 366: 130494, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34293544

RESUMO

Bioactive peptides have recently gained more research attention as potential therapies for the management of bodily disorders and metabolic syndromes of delicate health importance. On another note, there is a rising trend on a global scale for the consumption and adoption of fruit and vegetables for the fulfilment of dietary and health needs. Furthermore, fruits and vegetables are being more studied as base materials for the isolation of biologically functional components and accordingly, they have been investigated for their concomitant bioactive peptides. This review focuses on isolation and bio-functional properties of bioactive peptides from fruits and vegetables. This manuscript is potential in serving as a material collection for fundamental consultancy on peptides derived from fruits and vegetables, and further canvasses the necessitation for the use of these food materials as primal matter for such.


Assuntos
Frutas , Verduras , Dieta , Peptídeos
17.
Food Chem ; 367: 130668, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34343814

RESUMO

A novel polynomial correction method, order-adaptive polynomial correction (OAPC), was proposed to correct reflectance spectra with operator differences, and convolutional neural network (CNN) was used to develop analysis model to predict behenic acid in edible oils. With application of OAPC, CNN performed well with coefficient of determination of correction (R2cor) of 0.8843 and root mean square error of correction (RMSEcor) of 0.1182, outperforming partial least squares regression, support vector regression and random forest with OAPC, as well as the cases without OAPC. Based on 16 effective wavelengths selected by combination of bootstrapping soft shrinkage, random frog and Pearson's correlation, CNN and OAPC exhibited excellent performance with R2cor of 0.9560 and RMSEcor of 0.0730. Meanwhile, only 5% correction samples were selected by Kennard-Stone for OAPC. Overall, the proposed method could alleviate the impact of operator differences on spectral analysis, thereby providing potential to correct differences from measurement instruments or environments.


Assuntos
Óleos Vegetais , Máquina de Vetores de Suporte , Ácidos Graxos , Redes Neurais de Computação , Análise Espectral , Verduras
18.
Food Chem ; 366: 130611, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34388403

RESUMO

Anthocyanins are pigments abundant in fruits and vegetables, and commonly applied in foods due to attractive colour and health-promoting benefits. However, instability of anthocyanins leads to their easy degradation, reduced bioactivity, and colour fading in food processing, limiting their application and causing economic losses. Stability of anthocyanins depends on their own structures and environmental factors. For structural factors, modification including copigmentation, acylation and biosynthesis is a potential solution to increase anthocyanin stability due to forming stable structures. With regard to environmental factors, encapsulation such as microencapsulation, liposome and nanoparticles has been shown effectively to enhance the stability. We proposed the potential challenges and perspectives for the diversification of anthocyanin-rich products for food application, particularly, introduction of hazards, technical limitations, interaction with other ingredients in food system and exploration of pyranoanthocyanins. The integrated strategies are warranted for improving anthocyanin stabilization for promoting their further application in food industry.


Assuntos
Antocianinas , Frutas , Pigmentação , Extratos Vegetais , Verduras
19.
Food Chem ; 367: 130714, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34388632

RESUMO

The following qualitative screening and quantitative determination of 201 pesticides present a detailed optimization making use of design of experiments (DoE). The post-targeted screening took advantage of an upgradeable database to extend the survey further to perform a standard-free novel quantitation by liquid chromatography high resolution mass spectrometry (LC-HRMS). The fine tuning of instrumental parameters allowed the best method selectivity, sensitivity and reproducibility for the compounds under study. Among the factors considered, the heated electrospray source (HESI), the sample composition and the MS/MS acquisition modes were assessed, including the all-ion fragmentation (AIF) mode and different versions of the variable data independent acquisition (vDIA). The results of the optimization showed that selected HESI conditions, a methanol/water (1:1) sample composition and a vDIA acquisition method increased the signal for most compounds with a remarkable benefit on signal shape and intensity. The method showed adequate analytical performance when assessed in local produce.


Assuntos
Resíduos de Praguicidas , Praguicidas , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Frutas/química , Resíduos de Praguicidas/análise , Praguicidas/análise , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem , Verduras
20.
J Hazard Mater ; 421: 126756, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34352523

RESUMO

Widespread heavy metal pollution in soils has posed serious threat to vegetable production and food security, yet little is still known about heavy metal accumulation and distribution in the majority of vegetable crops. Here, we report the generation of a tissue atlas of cadmium accumulation in zucchini (Cucurbita pepo var. Giromontial), a globally important cucurbit crop, based on two-season experiment with six genotypes grown under cadmium contaminated soils. Plant growth and development as manifested by biomass, flowering time and plant architecture were unaffected by 10 mg/kg cadmium treatment, but high level of cadmium enrichment was detected in all genotypes. Roots accumulated the largest amount of cadmium, whereas the cadmium concentrations in fruits was also considerable. The exocarps of fruits possessed nearly half of the total cadmium in fruits, rendering it a "hotspot" of safety risk. Measurement of the thiol-containing chelates revealed that concentration of GSH but not PCs was correlated with the cadmium concentration in subdivided fruit tissues, suggesting a mechanism of phloem-specific transportation of cadmium in the form of Cd-GSH. Based on the collective data, a tentative model describing the relationship between long-distance phloem transport and cadmium distribution in sink organs is proposed. The implications for food safety are discussed.


Assuntos
Cádmio , Poluentes do Solo , Cádmio/análise , Inocuidade dos Alimentos , Raízes de Plantas/química , Poluentes do Solo/análise , Compostos de Sulfidrila , Verduras
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