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1.
J Agric Food Chem ; 67(41): 11331-11339, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31529945

RESUMO

Chiral pesticides are often produced and applied without distinguishing the difference of enantiomers, which sometimes leads to overuse and inaccurate risk assessment. Imazalil is a widely used chiral fungicide; its parent and major metabolite R14821 (imazalil-M) are usually detected in environmental and plant samples. The enantioselective bioactivity of imazalil enantiomers to seven typical pathogens (e.g., Fulvia fulva) was explored. S-(+)-Imazalil showed 3.00-6.59 times higher bioactivity than its antipode for selected pathogens. Molecular docking partly explained the mechanism of enantioselectivity in bioactivity. S-(+)-Imazalil had a stronger hydrophobic interaction and lower energy conformation with binding sites than R-(-)-imazalil. The acute toxicity of S-(+)-imazalil was 1.23-fold and 2.25-fold more than R-(-)-imazalil to P. subcapitata and D. magna, respectively. And, S-(+)-imazalil-M had 2.21-fold and 1.70-fold higher toxicity than R-(-)-imazalil-M to P. subcapitata and D. magna, respectively. However, R-(-)-imazalil was 1.21 times more toxic than S-(+)-imazalil to D. rerio. The enantioselective dissipation of imazalil and imazalil-M was explored under greenhouse conditions. High-effective S-(+)-imazalil preferentially enriched in leaf and fruit of tomato and cucumber, and no enantioselective degradation was found in soil. Imazalil-M enantiomers formed in cucumber, leaf of cucumber, and tomato, and the EF values fluctuated between 0.332 and 0.499. The results could provide information for more accurate assessment of imazalil; they implicated that using S-(+)-imazalil could reduce pesticide input and the risk to D. rerio.


Assuntos
Fungicidas Industriais/química , Imidazóis/química , Poluentes do Solo/química , Verduras/química , Poluentes Químicos da Água/química , Animais , Ascomicetos/efeitos dos fármacos , Clorófitas/efeitos dos fármacos , Cucumis sativus/química , Daphnia/efeitos dos fármacos , Estabilidade de Medicamentos , Frutas/química , Fungicidas Industriais/toxicidade , Imidazóis/toxicidade , Lycopersicon esculentum/química , Simulação de Acoplamento Molecular , Solo/química , Poluentes do Solo/toxicidade , Estereoisomerismo , Poluentes Químicos da Água/toxicidade
2.
J Agric Food Chem ; 67(36): 10145-10154, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31418564

RESUMO

2-Phenylethanol (2PE) is a representative aromatic aroma compound in tea (Camellia sinensis) leaves. However, its formation in tea remains unexplored. In our study, feeding experiments of [2H8]L-phenylalanine (Phe), [2H5]phenylpyruvic acid (PPA), or (E/Z)-phenylacetaldoxime (PAOx) showed that three biosynthesis pathways for 2PE derived from L-Phe occurred in tea leaves, namely, pathway I (via phenylacetaldehyde (PAld)), pathway II (via PPA and PAld), and pathway III (via (E/Z)-PAOx and PAld). Furthermore, increasing temperature resulted in increased flux into the pathway for 2PE from L-Phe via PPA and PAld. In addition, tomato fruits and petunia flowers also contained the 2PE biosynthetic pathway from L-Phe via PPA and PAld and increasing temperatures led to increased flux into this pathway, suggesting that such a phenomenon might be common among most plants containing 2PE. This represents a characteristic example of changes in flux into the biosynthesis pathways of volatile compounds in plants in response to stresses.


Assuntos
Camellia sinensis/metabolismo , Lycopersicon esculentum/química , Petunia/química , Álcool Feniletílico/metabolismo , Vias Biossintéticas , Flores/química , Frutas/química , Folhas de Planta/metabolismo , Temperatura Ambiente
3.
J Agric Food Chem ; 67(36): 10185-10194, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31423782

RESUMO

This research aimed to measure the impact of novel food processing techniques, i.e., pulsed electric field (PEF) and ohmic heating (OH), on carotenoid bioaccessibility and Caco-2 cell uptake from tomato juice and high-pressure processing (HPP) and PEF on the same attributes from kale-based juices, as compared with raw (nonprocessed) and conventional thermally treated (TT) juices. Lycopene, ß-carotene, and lutein were quantitated in juices and the micelle fraction using high-performance liquid chromatography (HPLC)-diode array detection and in Caco-2 cells using HPLC-tandem mass spectrometry. Tomato juice results were as follows: PEF increased lycopene bioaccessibility (1.5 ± 0.39%) by 150% (P = 0.01) but reduced ß-carotene bioaccessibility (28 ± 6.2%) by 44% (P = 0.02), relative to raw juice. All processing methods increased lutein uptake. Kale-based juice results were as follows: TT and PEF degraded ß-carotene and lutein in the juice. No difference in bioaccessibility or cell uptake was observed. Total delivery, i.e., the summation of bioaccessibility and cell uptake, of lycopene, ß-carotene, and lutein was independent of type of processing. Taken together, PEF and OH enhanced total lycopene and lutein delivery from tomato juice to Caco-2 cells as well as TT, and may produce a more desirable product due to other factors (i.e., conservation of heat-labile micronutrients, fresher organoleptic profile). HPP best conserved the carotenoid content and color of kale-based juice and merits further consideration.


Assuntos
Brassica/química , Carotenoides/metabolismo , Manipulação de Alimentos/métodos , Sucos de Frutas e Vegetais/análise , Lycopersicon esculentum/química , Preparações de Plantas/metabolismo , Transporte Biológico , Brassica/metabolismo , Células CACO-2 , Temperatura Alta , Humanos , Lycopersicon esculentum/metabolismo , Modelos Biológicos , Preparações de Plantas/química
4.
J Agric Food Chem ; 67(36): 10256-10264, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31433628

RESUMO

In this study, a simple and effective chiral analytical method was developed to monitor prothioconazole and prothioconazole-desthio at the enantiomeric level using supercritical fluid chromatography-tandem triple quadrupole mass spectrometry. The baseline enantioseparation for prothioconazole and prothioconazole-desthio was achieved within 2 min on a Chiralcel OD-3 column with CO2/0.2% acetic acid-5 mmol/L ammonium acetate 2-propanol (85:15, v/v) as the mobile phase at a flow rate of 1.5 mL/min and column temperature of 25 °C. The limit of quantitation for each enantiomer was 5 µg/kg, with a baseline resolution of >3.0. The results of enantioselective dissipation showed that R-(-)-prothioconazole was preferentially degraded in tomato, cucumber, and pepper under greenhouse conditions. S-(-)-prothioconazole-desthio was preferentially degraded in tomato and cucumber; however, R-(+)-prothioconazole-desthio was preferentially degraded in pepper. Results of this study may help to facilitate more accurate risk assessment of prothioconazole and its major metabolite in agricultural products.


Assuntos
Cucumis sativus/química , Fungicidas Industriais/química , Lycopersicon esculentum/química , Triazóis/química , Triazóis/metabolismo , Cromatografia com Fluido Supercrítico , Cucumis sativus/metabolismo , Lycopersicon esculentum/metabolismo , Piper nigrum/química , Piper nigrum/metabolismo , Estereoisomerismo , Espectrometria de Massas em Tandem , Verduras/química , Verduras/metabolismo
5.
J Chem Ecol ; 45(8): 693-707, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31367970

RESUMO

Crop domestication and selective breeding have altered plant defense mechanisms, influencing insect-plant interactions. A reduction in plant resistance/tolerance against herbivory is generally expected in domesticated species, however, limited efforts have been made to compare inducibility of plant defenses between wild and domesticated genotypes. In the present study, the inducibility of several plant defense mechanisms (e.g. defensive chemicals, trichomes, plant volatiles) were investigated, and the performance and preference of the herbivore Helicoverpa zea were measured in three different tomato genotypes; a) wild tomato, Solanum pimpinellifolium L. (accession LA 2093), b) cherry tomato, S. lycopersicum L. var. cerasiforme (accession Matts Wild Cherry), and c) cultivated tomato, S. lycopersicum L. var. Better Boy). Enhanced inducibility of defensive chemicals, trichomes, and plant volatiles in the cultivated tomato, and a higher level of constitutive plant resistance against herbivory in the wild genotype was observed. When comparing the responses of damaged vs. undamaged leaves, the percent reduction in larval growth was higher on damaged leaves from cultivated tomato, suggesting a higher induced resistance compared to other two genotypes. While all tomato genotypes exhibited increased volatile organic compound (VOCs) emissions in response to herbivory, the cultivated variety responded with generally higher levels of VOCs. Differences in VOC patterns may have influenced the ovipositional preferences, as H. zea female moths significantly preferred laying eggs on the cultivated versus the wild tomato genotypes. Selection of traits during domestication and selective breeding could alter allocation of resources, where plants selected for higher yield performance would allocate resources to defense only when attacked.


Assuntos
Lycopersicon esculentum/química , Mariposas/fisiologia , Solanum/química , Animais , Comportamento Animal/efeitos dos fármacos , Catecol Oxidase/metabolismo , Feminino , Genótipo , Herbivoria , Larva/fisiologia , Lycopersicon esculentum/genética , Lycopersicon esculentum/metabolismo , Oviposição/efeitos dos fármacos , Fenóis/análise , Folhas de Planta/química , Folhas de Planta/metabolismo , Folhas de Planta/parasitologia , Proteínas de Plantas/análise , Análise de Componente Principal , Inibidores de Proteases/química , Solanum/genética , Solanum/metabolismo , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/metabolismo , Compostos Orgânicos Voláteis/farmacologia
6.
J Sci Food Agric ; 99(14): 6535-6545, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31321777

RESUMO

BACKGROUND: Sofrito, a basic culinary technique widely used in the Mediterranean, may preserve dietary polyphenols and enhance their intake in the Mediterranean population. The aim of this study was to investigate if the sofrito technique improves the polyphenol extractability in a tomato-based sofrito sauce. RESULTS: A full factorial design was applied using mathematical models. The content of chlorogenic acid, ferulic acid hexoside and naringenin was higher in the sofrito sauce than in raw tomato. The bioaccessibility of some tomato polyphenols was enhanced by the presence of olive oil and they were protected from oxidation during the cooking process by the use of onion. CONCLUSION: The use of olive oil and onion in Mediterranean cooking as a base for sauces and dishes, with an appropriate cooking time, preserve the polyphenol content of food. Thus, Mediterranean cuisine may contribute to the health effects of the Mediterranean diet. © 2019 Society of Chemical Industry.


Assuntos
Culinária/métodos , Lycopersicon esculentum/química , Polifenóis/química , Dieta Mediterrânea , Azeite de Oliva/química , Cebolas/química
7.
Food Chem ; 300: 125232, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31352286

RESUMO

The mechanisms of main tomato carotenes (phytoene, phytofluene, lycopene and ß-carotene) intestinal absorption are still only partly understood. We thus compared carotene bioavailability in mice after gavage with carotene-rich oil-in-water emulsions. We also determined each carotene absorption profile along the duodenal-ileal axis of the intestine to identify their respective absorption sites and compared these profiles with the gene expression sites of their identified transporters, i.e. SR-BI and CD36. Our data show that phytofluene presented a significantly higher bioavailability compared to lycopene and ß-carotene (areas under the curve of 0.76 ±â€¯0.09 vs. 0.30 ±â€¯0.05, 0.09 ±â€¯0.05 and 0.08 ±â€¯0.01 µmol/L·h for phytofluene, phytoene, lycopene and ß-carotene, respectively). ß-Carotene was mostly converted in the proximal and median intestine. Phytoene and phytofluene accumulation tended to be more important in the distal intestine, which did not correlate with the proximal expression of both Scarb1 and CD36. Overall, these results highlight the high bioavailability of phytofluene.


Assuntos
Carotenoides/farmacocinética , Absorção Intestinal , Licopeno/farmacocinética , beta Caroteno/farmacocinética , Animais , Disponibilidade Biológica , Antígenos CD36/genética , Intestinos/efeitos dos fármacos , Lycopersicon esculentum/química , Masculino , Camundongos Endogâmicos C57BL , Período Pós-Prandial , Receptores Depuradores Classe B/genética
8.
Artigo em Inglês | MEDLINE | ID: mdl-31287378

RESUMO

A rapid and sensitive ultra-high-performance liquid chromatography-tandem mass spectrometry method, in conjunction with multiwalled carbon nanotube purification, was developed to determine the mefentrifluconazole levels in grapes, cucumbers, tomatoes, peppers, wheat, maize, eggs, milk, pork, chicken, and fish. After purification, tandem mass spectrometry of mefentrifluconazole required <3.0 min. Matrix-matched external standard curves were used to quantify the residual mefentrifluconazole. The method meets the requirements of the European Union Document SANTE/11813/2017. Quantification was linear between 5 and 500 µg/kg (R2 ≥ 0.9988), and both the intra- and interday relative standard deviations were ≤13.7%. Analyte recovery ranged from 81.5% to 107.6%. The limit of mefentrifluconazole quantification was 5 µg/kg for all matrices. The method successfully detected and quantified mefentrifluconazole that had been applied to cucumbers and tomatoes grown in a test field. These results imply that the proposed method is effective and reliable for detecting mefentrifluconazole residues in plant- and animal-derived foods.


Assuntos
Fluconazol/análogos & derivados , Fluconazol/análise , Análise de Alimentos , Contaminação de Alimentos/análise , Animais , Capsicum/química , Galinhas , Cromatografia Líquida de Alta Pressão , Cucumis sativus/química , Ovos/análise , Peixes , Lycopersicon esculentum/química , Leite/química , Carne Vermelha/análise , Alimentos Marinhos/análise , Espectrometria de Massas em Tandem , Fatores de Tempo , Triticum/química , Vitis/química , Zea mays/química
9.
Food Chem ; 298: 125040, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31261008

RESUMO

The effects of co-digestion of red cabbage with carrot, baby spinach and/or cherry tomato on the bioaccessibility of anthocyanins and carotenoids such as α-carotene, ß-carotene, lutein and lycopene were examined using a simulated in vitro gastro-intestinal digestion model. The individual vegetables and their mixtures were digested with and without added a standardised salad dressing. Bioaccessibility of total anthocyanins was enhanced by 10-15% (p < 0.05) when red cabbage was co-digested with the carotenoid-rich vegetables, except with carrot. In contrast, the co-digestion of red cabbage with carrot decreased bioaccessibility of total carotenoids by 21-33% (p < 0.05), and with cherry tomato by 42-56% (p < 0.05). The bioaccessibility of a given carotenoid varied depending on the vegetable matrix. Among the tested vegetable mixtures, red cabbage and baby spinach when co-digested demonstrated that anthocyanins and carotenoids were equally bioaccessible (total anthocyanin bioaccessibility of 62-66% and total carotenoid bioaccessibility of 66%).


Assuntos
Antocianinas/farmacocinética , Brassica/química , Carotenoides/farmacocinética , Lycopersicon esculentum/química , Verduras/química , Disponibilidade Biológica , Brassica/metabolismo , Daucus carota/química , Digestão , Humanos , Lycopersicon esculentum/metabolismo , Saliva , Spinacia oleracea/química , Verduras/metabolismo
10.
Food Chem ; 298: 125069, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31260991

RESUMO

The effects of ethanol treatment on quality characteristics of cherry tomatoes were investigated over 11 days of storage at room temperature (25 °C). Results showed that sensory quality was improved after ethanol treatment, with redder, softer fruits at the edible stage (11 days) compared with control fruit. In addition, the contents of ascorbic acid, sucrose and fructose were elevated after ethanol treatment as well as the concentration of 6-methyl-5-hepten-2-one. Conversely, decreased levels of methyl salicylate (MeSA), guaiacol, (Z)-3-hexenal and (E)-2-hexenal were observed. Selected consumers showed a preference for ethanol-treated cherry tomato fruits compared with controls. Taken together, 0.1% ethanol application has the potential to improve the quality characteristics of cherry tomatoes stored at room temperature.


Assuntos
Etanol/farmacologia , Lycopersicon esculentum/efeitos dos fármacos , Aldeídos/química , Ácido Ascórbico/análise , Cromatografia Líquida de Alta Pressão , Análise Discriminante , Aromatizantes/análise , Frutas/química , Frutas/efeitos dos fármacos , Frutas/metabolismo , Humanos , Análise dos Mínimos Quadrados , Lycopersicon esculentum/química , Lycopersicon esculentum/metabolismo , Salicilatos/química , Açúcares/análise , Temperatura Ambiente , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/isolamento & purificação
11.
Food Chem ; 298: 125062, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31280088

RESUMO

The industrial transformation of tomato (Lycopersicon esculentum Mill.) produces processed foods, such as dried tomatoes. In this study two varieties (SaAb and PerBruzzo), grown in three cropping systems (one conventional and two organic ones), were processed by two types of small-scale drying (oven or sun drying), over two years of production. The dried samples were analyzed for their non-volatile and volatile composition, relating the results with sensory analysis. The multivariate analysis performed on collected data allowed a detailed comparison of the effects of processing, year-to year variation and cropping systems. Results indicated that drying methods mainly influenced the composition and flavor profile, also affected by the production year. The cropping system significantly influenced some quality indices, such as the acid and sugar amounts, and the aldehydes, respectively higher and lower in organic samples. The comprehensive PCA analysis allowed discrimination of drying methods and, to a lesser extent, cropping systems.


Assuntos
Aromatizantes/química , Lycopersicon esculentum/química , Nariz Eletrônico , Aromatizantes/análise , Liofilização , Frutas/química , Frutas/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Lycopersicon esculentum/metabolismo , Agricultura Orgânica , Análise de Componente Principal , Estações do Ano , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/química
12.
Artigo em Inglês | MEDLINE | ID: mdl-31226007

RESUMO

In several studies focused on the residues of cyazofamid and its main metabolite 4-chloro-5-p-tolylimidazole-2-carbonitrile (CCIM) on tomato where it is widely used, CCIM has been shown to have higher acute toxicity than cyazofamid, and this is crucial to evaluate the potential food risk of cyazofamid and CCIM. In this study, the dissipation of cyazofamid and CCIM during tomato growth and tomato paste making process were assessed. The targeted compounds cyazofamid and CCIM were determined by LC-MS/MS. The results indicated that the half-life of cyazofamid was 4.6 days after applying in the field, and the maximum value of CCIM was 0.08 mg/kg at 3 days after the last application of cyazofamid, then gradually decreased. In addition, the concentrations of cyazofamid and CCIM were affected by different processing steps including washing, peeling, homogenisation, simmering, and sterilisation. Results showed that the mean losses of cyazofamid and CCIM were 92.3% and 75.2% after washing and peeling. The Processing Factor (PF) values were all less than 1. Especially for peeling, the PFs of cyazofamid and CCIM were 0.12 and 0.04, respectively.


Assuntos
Análise de Alimentos , Contaminação de Alimentos/análise , Manipulação de Alimentos , Imidazóis/análise , Imidazóis/metabolismo , Lycopersicon esculentum/química , Lycopersicon esculentum/crescimento & desenvolvimento , Nitrilos/análise , Sulfonamidas/análise , Sulfonamidas/metabolismo , Cromatografia Líquida , Lycopersicon esculentum/metabolismo , Nitrilos/metabolismo , Espectrometria de Massas em Tandem
13.
J Sci Food Agric ; 99(14): 6173-6181, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31250429

RESUMO

BACKGROUND: Tomato is one of the most important agricultural crops and it is characterized by a wide bioactive compound profile. However, little information is reported on its comprehensive polyphenol profile. In this work, 13 commercial tomato cultivars for industrial transformation were screened by ultra-high-pressure liquid chromatography coupled to quadrupole-time-of-flight mass spectrometry (UHPLC-QTOF-MS) for both free and bound phenolic profiles. Thereafter, the in vitro antioxidant activity of each cultivar was assessed by ferric reducing antioxidant power (FRAP) and oxygen radical absorbance activity (ORAC) assays. Multivariate statistics, i.e. orthogonal projection to latent structures discriminant analysis (OPLS-DA), were then used to model samples according to their distinct phenolic signatures, thus providing compounds that better discriminated between the distributions of the cultivars that were considered. RESULTS: More than 350 phenolic compounds could be identified across the samples that were considered: flavonoids (such as flavones and flavanols), hydroxycinnamic acids, lignans, and lower-molecular-weight phenolics were the most frequently observed classes of phenolics in tomato berries. Anthocyanins were the most abundant class among bound phenolics (being highest in the Leader F1 and Defender F1 cultivars), followed by tyrosols (mainly in Heinz cultivars). However, flavones and hydroxybenzoic acids were the most represented discriminant phenolics in the bound fraction. CONCLUSIONS: Untargeted metabolomics allowed significant differences in phenolic composition to be outlined across the tomato cultivars that were analyzed. Such differences were particularly evident regarding the free-to-bound phenolic ratio, hence allowing differences in the bioaccessibility of phenolics to be postulated. © 2019 Society of Chemical Industry.


Assuntos
Lycopersicon esculentum/química , Fenóis/química , Extratos Vegetais/química , Antocianinas/química , Antioxidantes/química , Cromatografia Líquida de Alta Pressão , Flavonoides/química , Frutas/química , Espectrometria de Massas
14.
Food Chem ; 296: 9-16, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31202311

RESUMO

Z-lycopene isomers are more bioavailable than all-E-lycopene, especially 5-Z-lycopene. Based on our observations, the addition of unblanched onion could favor Z-isomerization of lycopene (by more than 94%) during heating tomato-onion-extra virgin olive oil (EVOO) purees at 90 °C for 2 h. The increase in Z-lycopene was correlated linearly with the addition of unblanched onion, with R2 > 0.92, and increased rates of 5-Z-lycopene were 3-4 times higher than for 9-Z-lycopene and 13-Z-lycopene. Diallyl disulfide (DADS), formed by alliinase-catalyzed breakdown of non-volatile precursors in onion, contributed to these increases and correlated linearly (R2 > 0.79, 0-0.50 mg/g puree) with increased Z-lycopene. Increased rates of 5-Z-lycopene were also 3-4 times higher than for 9-Z-lycopene and 13-Z-lycopene. However, blanching of onion, in tomato-onion-EVOO purees, before heating, significantly decreased the effect of onion on Z-isomerization of lycopene.


Assuntos
Lipídeos/química , Licopeno/química , Lycopersicon esculentum/química , Cebolas/química , Compostos Alílicos/química , Cromatografia Líquida de Alta Pressão , Dissulfetos/química , Isomerismo , Licopeno/análise , Lycopersicon esculentum/metabolismo , Azeite de Oliva/química , Cebolas/metabolismo , Temperatura Ambiente
15.
J Agric Food Chem ; 67(25): 6930-6939, 2019 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-31150236

RESUMO

In many regions, reuse of reclaimed water (RW) is a necessity for irrigation. The presence of organic microcontaminants (OMCs) in RW and their translocation to plants may represent a risk of human exposure. Nevertheless, information available about real field crops is scarce and focused on a limited number of compounds. The novelty of this work relies on the application of a wider-scope analytical approach based on a multianalyte target analysis (60 compounds) and a suspect screening (>1300 compounds). This methodology was applied to real field-grown tomato crops irrigated with RW. The study revealed the presence of 17 OMCs in leaves (0.04-32 ng g-1) and 8 in fruits (0.01-1.1 ng g-1), 5 of them not reported before in real field samples. A health-risk assessment, based on the toxicological threshold concern (TTC) concept, showed that RW irrigation applied under the conditions given does not pose any threat to humans.


Assuntos
Frutas/química , Lycopersicon esculentum/metabolismo , Águas Residuárias/análise , Poluentes Químicos da Água/análise , Irrigação Agrícola , Transporte Biológico , Frutas/metabolismo , Humanos , Lycopersicon esculentum/química , Folhas de Planta/química , Folhas de Planta/metabolismo , Medição de Risco , Água/química , Poluentes Químicos da Água/metabolismo
16.
Food Chem ; 295: 300-310, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31174762

RESUMO

While fleshy fruit softening has long been mechanistically linked to cell wall disassembly, the importance of the fruit cuticle in water relations and firmness has been suggested through studies of the long-shelf life delayed fruit deterioration (dfd) tomato genotype. We tested the hypothesis that dynamic cuticle properties and composition affect tomato fruit transpiration and firmness and are influenced by environmental water availability, using dfd and two normally softening fruit cultivars, Ailsa Craig (AC) and M82, grown under control and water stress (WS) conditions. The effect of WS was also assessed following fruit detachment. WS increased fruit firmness, cuticle load, and the expression of cuticle biosynthetic genes, while reducing cuticle permeability and fruit transpiration rate in AC and M82, but not in dfd fruit. This study supports a direct relationship between fruit cuticle properties, transpiration and firmness, and provides insights into the adaptation of tomato genotypes to environments where water can be scarce.


Assuntos
Desidratação , Frutas/fisiologia , Lycopersicon esculentum/fisiologia , Armazenamento de Alimentos , Frutas/química , Frutas/metabolismo , Genótipo , Lycopersicon esculentum/química , Lycopersicon esculentum/metabolismo , Transpiração Vegetal , Água/metabolismo
17.
Environ Sci Pollut Res Int ; 26(22): 22464-22471, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31161542

RESUMO

A field experiment was conducted to study the persistence and dissipation pattern of a new molecule tetraniliprole on tomato fruits and soil. Tetraniliprole was sprayed at the rate of 60 g a.i. ha-1 and 120 g a.i. ha-1on the tomato crop. Tomato fruit samples were analyzed as per the method described by Bosta and Nageswara (Asian J Res Chem 8:383-388, 2015). The residues of tetraniliprole and its metabolite chinazolinon were estimated on HPLC equipped with RP C18 column and photo diode array detector. Initial deposits of tetraniliprole were 0.865 and 1.747 mg kg-1 on fruits and 0.092 and 0.177 mg kg-1 in the soil, respectively, from the two treatments at the rate 60 g a.i. ha-1 and 120 g a.i. ha-1. The residues on fruits dissipated to half in 2.7 and 3.49 days, respectively. Based on the persistence studies, a waiting period of 15 days is suggested on tomato fruit from consumer's safety point of view. The pesticide residues, left to a variable extent in the tomato after harvesting, are beyond the control of consumers and have deleterious effects on human health; hence, their residues reduction by various culinary processes were highlighted. Treated tomato fruit samples collected at 1, 3, and 5 days after application were also subjected to common household practices. Washing of tomato fruits by tap, lukewarm, and saline water reduce tetraniliprole residues up to 37.63, 44.67, and 61.49%, respectively. Microwave cooking of tomato provided >12% better relief from tetraniliprole residues in comparison with open pan cooking of 72.21%. Chinazolinon residues, a metabolite of tetraniliprole, were not detected in any analyzed processed tomato fruit sample.


Assuntos
Frutas/química , Lycopersicon esculentum/metabolismo , Resíduos de Praguicidas/análise , Solo/química , Cromatografia Líquida de Alta Pressão , Culinária , Meia-Vida , Humanos , Índia , Inseticidas/análise , Lycopersicon esculentum/química
18.
Food Chem ; 293: 220-225, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31151604

RESUMO

This study was conducted for quantitative determination of quercetin in food and fruit juice samples based on a green, fast, and accurate method namely, micro-cloud point extraction (MCPE). The proposed MCPE is essentially a miniaturized form of traditional cloud point extraction (CPE) in which only a few microliters of micellar extracting phase is sufficient for determination. Factors influencing the extraction efficiency, such as amount of Triton X-114 (5%, v/v), effect of pH, amount of Na2SO4 salt (5%, w/v) and time of centrifugation were investigated and optimized by experimental design. Under the optimized condition, the calibration range was found to be linear over 10-100 ng mL-1 with the limit of detection of 2.2 ng mL-1. The relative standard deviation of 2.8%, was obtained on a 30 ng mL-1quercetin standard solution (n = 3). Finally, the proposed method was successfully applied for the determination of quercetin in onion, tomato, apple and orange juice samples.


Assuntos
Análise de Alimentos/métodos , Sucos de Frutas e Vegetais/análise , Quercetina/análise , Calibragem , Centrifugação , Fracionamento Químico , Concentração de Íons de Hidrogênio , Limite de Detecção , Lycopersicon esculentum/química , Lycopersicon esculentum/metabolismo , Cebolas/química , Cebolas/metabolismo , Polietilenoglicóis/química , Quercetina/isolamento & purificação , Espectrofotometria/normas
19.
J Agric Food Chem ; 67(28): 8045-8052, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31241326

RESUMO

n-Octadecylamine was adopted as a cleanup agent to develop a novel solidification of a switchable solvent-based QuEChERS method. At higher temperatures (such as 55 °C), n-octadecylamine can melt into a liquid, allowing effective extraction of matrix interferences in acetonitrile solution (i.e., in dispersive liquid-liquid microextraction). At lower temperatures, n-octadecylamine carrying matrix interferences can rapidly solidify and easily separate from the acetonitrile solution. The results demonstrated that n-octadecylamine possessed a better ability to remove matrix interferences and reduce matrix effects than those of traditional solid-phase dispersive extraction cleanup agents of primary secondary amine and octadecyl bonded silica gel. By coupling it with gas chromatography-mass spectrometry, the proposed method was applied to the detection of 16 pesticides in cucumber. The recoveries were from 80.9 to 112.6% with relative standard deviations less than 12.9%. Satisfactory results were also obtained for the detection of 16 pesticides in pear, orange, apple, pepper, lettuce, and tomato.


Assuntos
Frutas/química , Microextração em Fase Líquida/métodos , Resíduos de Praguicidas/química , Resíduos de Praguicidas/isolamento & purificação , Verduras/química , Acetonitrilos/química , Aminas/química , Citrus sinensis/química , Cucumis sativus/química , Cromatografia Gasosa-Espectrometria de Massas , Alface/química , Microextração em Fase Líquida/instrumentação , Lycopersicon esculentum/química , Malus/química , Solventes/química
20.
J Sci Food Agric ; 99(12): 5368-5376, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31062362

RESUMO

BACKGROUND: Famoxadone is a pesticide that is used to control fungal diseases and its dissipation in vegetables should be monitored. For that purpose, liquid chromatography coupled to mass spectrometry has been used. RESULTS: The dissipation of famoxadone has been monitored in cucumber, cherry tomato and courgette under greenhouse conditions at different doses (single and double), using ultra high-performance liquid chromatography coupled to Orbitrap mass spectrometry (Thermo Fisher Scientific, Bremen, Germany). The concentration of famoxadone increased slightly just after the application of the commercial product and then decreased. The half-lives (DT50 ) of famoxadone are different for each matrix, ranging from 2 days (courgette single dose) to 10 days (cucumber double dose). The main metabolites, 4-phenoxybenzoic acid and 1-acetyl-2-phenylhydrazine, were not detected in vegetable samples. Other metabolites described by the European Food and Safety Authority, such as IN-JS940 [(2RS)-2-hydroxy-2-(4-phenoxyphenyl)propanoic acid], IN-KF015 [(5RS)-5-methyl-5-(4-phenoxyphenyl)-1,3-oxazolidine-2,4-dione] and IN-MN467 [(5RS)-5-methyl-3-[(2-nitrophenyl)amino]-5-(4-phenoxyphenyl)-1,3-oxazolidine-2,4-dione], were detected in the three matrices. Untargeted analysis allowed for the putative elucidation of a new metabolite of famoxadone in cucumber (up to 290 µg kg-1 ) and cherry tomato (up to 900 µg kg-1 ) samples. CONCLUSION: The dissipation of famoxadone has been investigated in three vegetables: tomato, cucumber and courgette. The persistence of famoxadone was low in the three matrices (DT50 less than 10 days). Metabolites of famoxadone were monitored, detecting IN-JS940, IN-MN467 and IN-KF015, and the putative elucidation of a new metabolite of famoxadone was performed by applying software tools. © 2019 Society of Chemical Industry.


Assuntos
Cucumis sativus/química , Lycopersicon esculentum/química , Estrobilurinas/química , Verduras/química , Cromatografia Líquida de Alta Pressão , Cucumis sativus/crescimento & desenvolvimento , Cucumis sativus/metabolismo , Alemanha , Humanos , Lycopersicon esculentum/crescimento & desenvolvimento , Lycopersicon esculentum/metabolismo , Espectrometria de Massas , Estrobilurinas/metabolismo , Verduras/crescimento & desenvolvimento , Verduras/metabolismo
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