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1.
Se Pu ; 37(9): 1019-1025, 2019 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-31642308

RESUMO

An analytical method for the determination of 34 pesticide residues in plant-derived foods was established using an automated QuEChERS sample preparation system combined with high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The sample extraction and dispersive solid-phase extraction in the manual QuEChERS method were combined using the vortex vibration and centrifugation functions of the automated QuEChERS sample preparation system. The operating parameters and pretreatment steps were optimized, and the analytes were detected in the multiple reaction monitoring (MRM) mode. The quantification analysis was performed by the matrix-matched external standard method. The automated and the manual QuEChERS methods were compared from the methodological verification standpoint. The calibration curves showed good linearity in a certain range, and the correlation coefficients (R2) were greater than 0.99. The limits of detection and limits of quantification were 0.76-3.60 µg/kg and 2.28-10.80 µg/kg, respectively. Moreover, the recoveries ranged from 53.0% to 125.2%, and the relative standard deviations (RSDs) were less than 1.59% (n=5). The results obtained by the manual QuEChERS method were not significantly different from those obtained by the automated QuEChERS method. This method can effectively reduce the labor intensity and probability of error in the determination of pesticide residues.


Assuntos
Contaminação de Alimentos/análise , Resíduos de Praguicidas/análise , Verduras/química , Cromatografia Líquida de Alta Pressão , Extração em Fase Sólida , Espectrometria de Massas em Tandem
2.
J Agric Food Chem ; 67(39): 10871-10879, 2019 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31517482

RESUMO

This study evaluated the effect of triterpenoids from edible mushroom Poria cocos on intestinal epithelium integrity and revealed the transcriptional regulatory pathways that underpin restorative mechanisms in the gut. Based on computational docking studies, transcriptional activation experiments and glucocorticoid receptor (GR) protein immunofluorescence localization assays in cultured cells, 16α-hydroxytrametenolic acid (HTA) was discovered as a novel GR agonist in this study. HTA ameliorates TNF-α-induced Caco-2 monolayer intestinal epithelial barrier damage and suppressed activation of phosphatidylinositol 3-kinase (PI3K) and protein kinase B (Akt), which attenuated downstream IκB and nuclear factor kappa-B (NF-κB) phosphorylation through GR activation. Moreover, HTA prevented NF-κB translocation into the nucleus and binding to its cis-element and suppressed lipopolysaccharide-induced downstream NO production and pro-inflammatory cytokines at both protein and mRNA expression levels. In conclusion, HTA from P. cocos improves intestinal barrier function through a GR-mediated PI3K/Akt/NF-κB signaling pathway and may be potentially exploited as a supportive dietary therapeutic strategy for restoring gut health.


Assuntos
Mucosa Intestinal/efeitos dos fármacos , NF-kappa B/metabolismo , Fosfatidilinositol 3-Quinase/metabolismo , Extratos Vegetais/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores de Glucocorticoides/metabolismo , Triterpenos/farmacologia , Wolfiporia/química , Células CACO-2 , Humanos , Proteínas I-kappa B/genética , Proteínas I-kappa B/metabolismo , Mucosa Intestinal/metabolismo , Simulação de Acoplamento Molecular , NF-kappa B/genética , Fosfatidilinositol 3-Quinase/genética , Fosforilação , Extratos Vegetais/química , Proteínas Proto-Oncogênicas c-akt/genética , Receptores de Glucocorticoides/genética , Transdução de Sinais/efeitos dos fármacos , Triterpenos/química , Verduras/química
3.
J Agric Food Chem ; 67(38): 10800-10812, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31490681

RESUMO

In this work, a highly efficient pesticide residue screening and quantification method was established using ultrahigh-performance liquid chromatography-tandem quadrupole time-of-flight mass spectrometry based on in-source fragmentation. Over 400 pesticides were tested, among which 96 pesticides displayed in-source fragmentation. A novel concept of in-source fragment fraction was proposed to evaluate the extent of in-source fragmentation, which was found to be chemical structure- and source parameter-dependent. A high-resolution MS/MS library containing 403 pesticides and 126 fragments was created and was applied for library searching of pesticide residues in vegetables and fruits. The introduction of in-source fragments effectively circumvented misannotation and occurrence of false negatives. The quantification ability for the fragments was validated in terms of recovery, linearity, and limit of quantification and its superiority to the parent pesticides was established. Finally, the proposed method was applied for the analysis of real samples and proficiency test samples, and false negative results were successfully avoided in the analysis.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Frutas/química , Resíduos de Praguicidas/química , Espectrometria de Massas em Tandem/métodos , Verduras/química , Contaminação de Alimentos/análise , Limite de Detecção
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 Agric Food Chem ; 67(37): 10330-10341, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31469960

RESUMO

Fomitopsis pinicola (Sw. Ex Fr.) Krast has been commonly used as a health food source and antitumor agent. To uncover bioactive key composition of F. pinicola, in our study, we investigated the chemical constituents of a methanol extract of F. pinicola and thirty-five lanostane-type tritetpenoids; 13 new compounds (1-13) and twenty-two known analogues (14-35) were isolated. Among them, compounds 1-9 were C30 lanostane triterpenoids and triterpene sugar esters, while compounds 10-13 were C31 triterpenoids and triterpene sugar esters. Their structures and absolute configurations were elucidated by extensive 1D, 2D NMR, MS, and IR spectra. Furthermore, cytotoxic activities of all isolates against five human tumor cell lines (HL-60, A549, SMMC-7721, MCF-7, and SW480) were evaluated. The results showed that compounds 12, 14, 17, 18, 22, and 23 displayed cytotoxic effects against five human tumor cell lines with IC50 values ranging from 3.92-28.51 µM. Meanwhile, compounds 9 and 35 exhibited selected inhibitory activities against HL-60, SMMC-7721, and MCF-7 with IC50 values in the range of 13.57-36.01 µM. Furthermore, the flow cytometry analysis revealed that compounds 17, 22, and 35 induced apoptosis in HL-60 cell lines. Their structure-activity relationships were preliminarily reported. These findings indicate the vital role of triterpenoids and their glycosides in explaining antitumor effects of F. pinicola and provide important evidence for further development and utilization of this fungus.


Assuntos
Coriolaceae/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Triterpenos/química , Triterpenos/farmacologia , Verduras/química , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Glicosídeos/química , Glicosídeos/farmacologia , Humanos , Estrutura Molecular , Relação Estrutura-Atividade
6.
J Agric Food Chem ; 67(33): 9362-9370, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31368700

RESUMO

This manuscript presents an effective and robust method for simultaneous stereoselective determination of two pyrethroid insecticides, tetramethrin and α-cypermethrin in different food products by high-performance liquid chromatography. Enantioseparation was carried out using reversed-phase chromatography, and the influences of four polysaccharide-based chiral columns, mobile phase composition, and column temperature on retention were fully investigated. Satisfactory separation was obtained on Chiralpak IG column using acetonitrile-water (75:25, v/v) under isocratic conditions. To extract and purify the target analytes from food matrices, matrix solid-phase dispersion was employed with C18 as dispersant and primary secondary amine as well as graphitized carbon black as cleanup sorbents. Response surface method based on Box-Behnken design was implemented to assist optimization of the extraction variables. Then, method validation was done in real samples including specificity, linearity, sensitivity, trueness, precision, as well as stability, and its analytical performance fulfills the criteria recommended by the European Union SANTE/11945/2015, demonstrating its applicability in studying the stereochemistry of chiral tetramethrin and α-cypermethrin in food products.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Grão Comestível/química , Frutas/química , Inseticidas/química , Piretrinas/química , Verduras/química , Cromatografia de Fase Reversa/métodos , Contaminação de Alimentos/análise , Inseticidas/isolamento & purificação , Piretrinas/isolamento & purificação , Extração em Fase Sólida , Estereoisomerismo
7.
Int J Food Microbiol ; 305: 108257, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31276954

RESUMO

Freezing vegetables requires pre-treatments to reduce microbial load and destroy enzymes that impair the frozen product quality. So far blanching has been the most effective pre-treatment, preferred by the food industry, despite its severity: heating up to temperatures close to 100 °C for 1-3 min causes sensory and texture changes in most horticultural products. Alternative blanching treatments, using UV-C radiation combined with milder thermal treatments or with thermosonication, may improve the quality of the final frozen vegetables. Zucchini (Cucurbita pepo L.), the vegetable under study, has an availability in fresh restricted to a season, needing therefore to be often frozen to be used throughout the year. In this study, its surface was first inoculated with two vegetable contaminants, Enterococcus faecalis and Deinococcus radiodurans cells, which are resistant, respectively, to high temperatures and to radiation and then submitted to several blanching treatments, single or combined, and the effect on these microorganisms reduction was evaluated. As single treatments, water blanching (the control treatment, as it is the blanching treatment traditionally used) was applied up to 180 s at temperatures ranging from 65 to 90 °C, and UV-irradiation applied in continuous. As combined pre-treatments, water blanching combined with UV-C (continuous or in pulses), and thermosonication (20 kHz at 50% of power) combined with UV-C pulses were also studied. The continuous UV-C radiation incident irradiance was 11 W/m2 up to 180 s, and the pulses at incident radiance of 67 W/m2, lasting 3.5 s each (35 pulses). Mathematical modeling of bacterial reduction data was carried out using the Bigelow, the Weibull and Weibull modified models, and estimation of their respective kinetic parameters proved that the latter models presented a better fit below 75 °C. The best results proved to be the combination of water blanching at temperatures as low as 85 °C during <2 min with 25 pulses of UV-C (incident irradiance of 67 W/m2) or thermosonication at 90 °C also combined with UV-C pulses, both resulting in 3 log reductions of both microorganisms under study. These results proved to overcome what industry is requiring so far (a 2 log microbial reduction in 3 min), hence minimizing quality changes of frozen zucchini.


Assuntos
Cucurbita/química , Cucurbita/microbiologia , Deinococcus/fisiologia , Enterococcus faecalis/fisiologia , Conservação de Alimentos/métodos , Verduras/química , Verduras/microbiologia , Carga Bacteriana , Deinococcus/genética , Deinococcus/isolamento & purificação , Enterococcus faecalis/genética , Enterococcus faecalis/isolamento & purificação , Congelamento , Temperatura Ambiente , Água/análise
8.
Ecotoxicol Environ Saf ; 182: 109445, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31330408

RESUMO

In this study, a new, high-efficiency and sensitive method was determined to simultaneous analyze the residue of pyraclostrobin, picoxystrobin and its metabolite BF-500-3 in pepper fruit using modified QuEChERS pretreatment combined with ultra performance liquid chromatography-tandem mass spectrometry. The clean-up steps of QuEChERS procedure were optimized using the chemometric tools. Models of stepwise regression and surface response demonstrated that the optimal sorbent mixtures were 40 mg nano-zirconia + 10 mg C18 for pyraclostrobin and picoxystrobin and 30 mg nano-zirconia + 20 mg C18 for BF-500-3. The optimized purification procedures provided satisfactory recoveries for all tested fungicides with rates between 91% and 107% and relative standard deviations between 3.7% and 9.6%. The limits of detection and quantification were in the range of 0.0360-0.272 µg/kg and 0.120-0.910 µg/kg. Based on this method, the dissipation of pyraclostrobin, picoxystrobin and its metabolite in pepper fruit were determined under field conditions. Pyraclostrobin and picoxystrobin degraded rapidly with half-lives of 5.53-7.02 and 5.97-7.82 days and 5.09 and 5.68 days in 2016 and 2017, respectively. The residue levels of BF-500-3 increased first and then decreased. The terminal residues of all fungicides were below the maximum residue limits (MRLs). This research can not only provide guidance for the reasonable usage of pyraclostrobin and picoxystrobin in agriculture but also give a reference for the Chinese government to establish the MRL for pyraclostrobin in pepper.


Assuntos
Fungicidas Industriais/análise , Resíduos de Praguicidas/análise , Estrobilurinas/análise , Verduras/química , Agricultura , Cromatografia Líquida/métodos , Frutas/química , Espectrometria de Massas em Tandem/métodos
9.
Ecotoxicol Environ Saf ; 182: 109401, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31272024

RESUMO

Chronic impact will last from a sudden pollution accident, however, potential adverse effects of heavy metal(loid)s are overlooked when pollution decreased during years of equilibration. Here, we assessed the potential health risks of heavy metal(loid)s via intake of vegetables from fields affected by the smelting wastewater spill eight years later, basing on site-specific target hazard quotient (STHQ) and cancer risk (SCR) models. Results showed kohlrabi, lettuce and garlic had significant high concentrations of Sb (10.4 mg kg-1), Pb (21.0 mg kg-1), Cd (6.49 mg kg-1), and Zn (441 mg kg-1), and sweet potato and garlic enriched high levels of As (19.6 mg kg-1) and Cu (14.1 mg kg-1), respectively. Transfer factors of metal(loid)s from soil to plants were enhanced by high soluble metal(loid) concentrations, and Sb, As, Pb and Cd in most edible tissues exceeded the contamination limitations for food in China and FAO/WHO. Chinese cabbage had significant high STHQ of As (adult 9.31 and child 19.8) and Sb (adult 0.76 and child 1.61) (p < 0.05), and the highest STHQ of Cd (adult 1.41 and child 3.02) was in lettuce, whereas the highest STHQ of other elements from vegetables were below 1. However, the non-carcinogenic risks based on total STHQ values of these vegetables were several times higher than the acceptable level of 1. In addition, the total SCR values at 5% were hundreds times of safety level of 5.0 × 10-5 set by International Commission on Radiological Protection. Considering food frequency and metal(loid) levels, long-term consumption of local vegetables, especially lettuce and Chinese cabbage, are likely to increase non-carcinogenic and carcinogenic (e.g. As and Cd) health risks. Child's health risk of toxic elements was far greater than adult. This study might serve as a case study of long-term adverse impact for other pollutant incidents. People should pay attention to human health through food chain, and the government should solve the outstanding environmental problems that harm the health of the masses.


Assuntos
Exposição Dietética/estatística & dados numéricos , Monitoramento Ambiental , Metais Pesados/análise , Poluentes do Solo/análise , Verduras/química , Acidentes , Adulto , Vazamento de Resíduos Químicos , Criança , China , Poluentes Ambientais , Humanos , Metalurgia , Medição de Risco , Solo , Águas Residuárias/química
10.
Food Chem ; 300: 125188, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31336274

RESUMO

An effective, simple and sensitive analytical method has been developed employing liquid chromatography coupled with tandem mass spectrometry and validated for estimation of five organophosphate pesticides at trace levels in six fruits and twelve vegetables. Plackett-Burman design and central composite design was used to screen and optimize the significant factors in modified QuEChERS (quick, easy, cheap, effective, rugged and safe) extraction method. The method evaluation was done by matrix-matched calibration with linearity ranging from 5 to 500 µg/L with a correlation coefficient more than 0.990. The detection and quantification limit ranged from 0.1 to 1.0 µg/kg and 0.5 to 5 µg/kg, respectively. The mean recoveries were in the range of 76.89-110.30 % with the relative standard deviation less than 13.26% for all pesticides. Further, the method developed was applied to analyze real samples cultivated in the hill areas of Nilgiris, South India.


Assuntos
Fracionamento Químico/métodos , Contaminação de Alimentos/análise , Organofosfatos/análise , Praguicidas/análise , Calibragem , Cromatografia Líquida/métodos , Análise de Alimentos/métodos , Frutas/química , Índia , Análise Multivariada , Organofosfatos/isolamento & purificação , Resíduos de Praguicidas/análise , Resíduos de Praguicidas/isolamento & purificação , Praguicidas/isolamento & purificação , Sensibilidade e Especificidade , Espectrometria de Massas em Tandem/métodos , Verduras/química
11.
Food Chem ; 300: 125220, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31352288

RESUMO

Fruits and vegetables play an important role in human nutrition. Study of the contamination sources which result from farming activities is of importance. For this reason, a chitosan-graphene oxide nanocomposite film was prepared and implemented as the extractive phase in thin film microextraction of six organophosphate residues (OPPs) in the samples using high-performance liquid chromatography. The optimized method was validated and the limits of detection (0.7-1.2 µg l-1), limits of quantification (2.3-4.0 µg l-1) and linear dynamic range (2.0-1000.0 µg l-1) were obtained. Principal component analysis revealed clustering of the fruit and vegetable samples based on the selected (OPPs) into two groups of unwashed-unpeeled and peeled-washed. This mapping was further investigated using descriptive method of boxplot. Washing and peeling of the samples, reduced the presence of OPPs to half or one third of interquartile range found in the unpeeled and unwashed samples.


Assuntos
Contaminação de Alimentos/análise , Frutas/química , Organofosfatos/análise , Resíduos de Praguicidas/análise , Verduras/química , Cromatografia Líquida de Alta Pressão/métodos , Análise de Alimentos/instrumentação , Análise de Alimentos/métodos , Análise de Alimentos/estatística & dados numéricos , Grafite/química , Limite de Detecção , Nanoestruturas/química , Óxidos/química , Análise de Componente Principal , Reprodutibilidade dos Testes , Microextração em Fase Sólida/instrumentação , Microextração em Fase Sólida/métodos
12.
Food Chem ; 299: 125124, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31288163

RESUMO

Inflammation plays a key role in diseases such as diabetes, asthma, cardiovascular diseases and cancer. Diet can influence different stages of inflammation and can have an important impact on several inflammatory diseases. Increasing scientific evidence has shown that polyphenolic compounds, such as flavonoids, which are found in fruits, vegetables, legumes, or cocoa, can have anti-inflammatory properties. Recent studies have demonstrated that flavonoids can inhibit regulatory enzymes or transcription factors important for controlling mediators involved in inflammation. Flavonoids are also known as potent antioxidants with the potential to attenuate tissue damage or fibrosis. Consequently, numerous studies in vitro and in animal models have found that flavonoids have the potential to inhibit the onset and development of inflammatory diseases. In the present review, we focused in flavonoids, the most abundant polyphenols in the diet, to give an overview of the most recent scientific knowledge about their impact on different inflammatory diseases.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Doenças Cardiovasculares/tratamento farmacológico , Flavonoides/farmacologia , Inflamação/tratamento farmacológico , Neoplasias/tratamento farmacológico , Animais , Anti-Inflamatórios/análise , Antioxidantes/análise , Cacau/química , Doenças Cardiovasculares/patologia , Dieta , Fabaceae/química , Flavonoides/análise , Frutas/química , Humanos , Neoplasias/patologia , Polifenóis/análise , Polifenóis/farmacologia , Verduras/química
13.
Sci Total Environ ; 690: 965-972, 2019 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-31302560

RESUMO

The effects of grilling on health risks posed by polycyclic aromatic hydrocarbons (PAHs) in food remain poorly understood. The changes of concentrations, distributions, and risks of PAHs in vegetables and animal-based foods before and after grilling were investigated in this study. The sum of 16 (∑16) PAH concentrations in grilled vegetables and grilled animal-based foods were 60.4-1936 and 69.1-4668 ng/g, respectively. Grilling markedly increased the ∑16 PAH concentrations in most foods analyzed. Grilling clearly increased the low-molecular-weight PAH contributions to the ∑16 PAH concentrations in vegetables but increased the heavier PAH contributions to the ∑16 PAH concentrations in some animal-based foods. With the grilling, the total benzo[a]pyrene-equivalent concentrations of the 16 PAHs in Chinese chives and enoki mushrooms and most animal-based foods were improved significantly. Source assessments indicated that environmental sources contributed PAHs to the raw foods and high-temperature pyrolysis during grilling contributed large proportions of the PAHs in the grilled foods. The carcinogenic risks to humans from the exposure of PAHs in vegetables and animal-based foods were estimated. Grilling increased the total risks of PAHs in vegetables and animal-based foods by factors of 3.12 and 5.49, respectively. Total risks of PAHs in the 11 foods were 3.43 times higher when the foods were grilled than when raw. The results suggested that the negative effects of grilling on human health should be of great concern.


Assuntos
Exposição Dietética/estatística & dados numéricos , Poluentes Ambientais/análise , Carne/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes do Solo/análise , Verduras/química , Culinária/métodos , Humanos
14.
Food Chem ; 298: 125028, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31260995

RESUMO

A robust and sensitive method utilising a hybrid ion chromatography tandem mass spectrometry system (IC-MS/MS) for the simultaneous determination of nine (9) highly polar anionic pesticides (chlorate, ethephon, fosetyl aluminium, glufosinate, glyphosate, N-acetyl AMPA, N-acetyl glyphosate, perchlorate and phosphonic acid) in fruit and vegetables is described. Mean recoveries (n = 6) at two fortification levels ranged from 83 to 112% with %CVs in the range 3-14%. The linearity range was 0.005-0.4 mg kg-1 and R2 values were >0.99 and the sensitivity of the method allowed (20× or 30×) dilution of samples. Provision of qualitative determination of aminomethylphosphonic acid (AMPA) was also facilitated via minor modification of the chromatographic conditions. Compliance with method validation criteria, survey results from the statutory UK/EU Pesticide Residues in Food 2018 programmes i.e. pea, pineapple, melon and successful z-scores for a UK proficiency testing scheme sample (ethephon in pineapple) demonstrate successful application of this IC-MS/MS method.


Assuntos
Contaminação de Alimentos/análise , Frutas/química , Resíduos de Praguicidas/análise , Espectrometria de Massas em Tandem/métodos , Verduras/química , Ânions/análise , Ânions/química , Cromatografia Líquida/métodos , União Europeia , Análise de Alimentos/métodos , Limite de Detecção , Compostos Organofosforados , Resíduos de Praguicidas/química , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/instrumentação
15.
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
16.
J Sci Food Agric ; 99(14): 6474-6481, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31294829

RESUMO

BACKGROUND: Kimchi, a Korean food, is now produced and consumed in many other countries. In this study, the macro, trace, and toxic element content in varieties of kimchi from Korea and China was evaluated. A health-risk assessment, involving the calculation of estimated dietary intake values, was undertaken. To discriminate among samples with different origins, linear discriminant analysis (LDA) and principal component analysis (PCA) were applied. RESULTS: The analytical methods used for analyses were successfully validated. In the quantification of elements, no significant differences were detected in the concentrations of the elements that were analyzed. Based on the fresh weight of kimchi, among the macro elements, the concentrations of Na and K were relatively high, with values of 4181.9-9919.8 mg kg-1 and 1661.8-6623.5 mg kg-1 , respectively. Among the trace elements that were analyzed, zinc in Korean samples, and strontium in Chinese samples showed the highest concentrations, at 2.67 and 2.98 mg kg-1 , respectively. Concentration levels of the toxic trace elements were within permissible limits. The amount of daily intake and provisional daily intake of each element calculated based on kimchi intake confirmed its safety for consumption. Linear discriminant analysis and PCA successfully discriminated among the samples of Chinese and Korean origin. CONCLUSION: The provisional daily intake of the toxic elements was within provisional tolerable daily intake values. The normal intake of kimchi could not pose a threat upon consumption. © 2019 Society of Chemical Industry.


Assuntos
Alimentos Fermentados/análise , Oligoelementos/análise , Verduras/química , China , Qualidade de Produtos para o Consumidor , Análise Discriminante , Humanos , Análise de Componente Principal , República da Coreia , Medição de Risco , Oligoelementos/toxicidade
17.
J Agric Food Chem ; 67(33): 9286-9294, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31339733

RESUMO

Natural aryl hydrocarbon (AHR) ligands have been identified in food and herbal medicines, and they may exhibit beneficial activity in humans. In this study, white button (WB) feeding significantly decreased AHR target gene expression in the small intestine of both conventional and germ-free mice. High-performance liquid chromatography (HPLC) fractionation and ultra-high-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) combined with an AHR-responsive cell-based luciferase gene reporter assay were used to isolate and characterize benzothiazole (BT) derivatives and 6-methylisoquinoline (6-MIQ) as AHR modulators from WB mushrooms. The study showed dose-dependent changes of AHR transformation determined by the cell-based luciferase gene reporter assay and transcription of CYP1A1 in human Caco-2 cells by BT derivatives and 6-MIQ. These findings suggested that WB mushroom contains new classes of natural AHR modulators and demonstrated HPLC fractionation and UHPLC-MS/MS combined with a cell-based luciferase gene reporter assay as a useful approach for isolation and characterization of the previously unidentifed AHR modulators from natural products.


Assuntos
Agaricus/química , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Receptores de Hidrocarboneto Arílico/genética , Animais , Benzotiazóis/química , Benzotiazóis/isolamento & purificação , Benzotiazóis/farmacologia , Linhagem Celular , Cromatografia Líquida de Alta Pressão , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1A1/metabolismo , Genes Reporter , Humanos , Isoquinolinas/química , Isoquinolinas/isolamento & purificação , Isoquinolinas/farmacologia , Ligantes , Camundongos , Extratos Vegetais/farmacologia , Receptores de Hidrocarboneto Arílico/metabolismo , Espectrometria de Massas em Tandem , Ativação Transcricional/efeitos dos fármacos , Verduras/química
18.
J Food Sci ; 84(7): 1888-1899, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31237979

RESUMO

The chemical and sensory quality of field-grown vegetables may be influenced by cultivar choice and agronomic factors but knowledge is lacking on the new rapeseed vegetables. White- and yellow-flowering rapeseed cultivars were tested in two seasonally different field studies in Denmark at three different growing stages by early sowing the first year and late sowing the second year. Content of glucosinolates (GLSs) was analyzed, and the sensory quality of baby leaf samples was evaluated. The GLS content differed among cultivars across years in all growing stages, with biennial cultivars having the highest GLS content. In the second year, a higher content of all identified GLSs was found at two growing stages except for neoglucobrassicin and gluconasturtiin, compared to the first year. On the contrary, higher contents of all identified GLSs were found at a third stage in the first year except for progoitrin and 4-methoxy glucobrassicin. Sensory evaluation of bitterness revealed differences among cultivars, higher intensities of bitterness in biennial cultivars, and a relationship between bitterness and content of bitter-tasting and total GLSs. The effect of repeated harvesting on GLS content differed between the years and no general pattern was seen, except that the composition of individual GLSs was comparable for the biennial cultivars. We conclude that growing season and life cycle had a stronger influence on GLS content than stage at harvest. The link between bitter-tasting GLSs and bitterness revealed that life cycle and seasonal effects affected the sensory profile of baby leaf rapeseed thereby making a healthier product due to high content of health-beneficial GLSs.


Assuntos
Brassica rapa/química , Glucosinolatos/análise , Verduras/química , Brassica rapa/crescimento & desenvolvimento , Cor , Humanos , Indóis/análise , Folhas de Planta/química , Estações do Ano , Paladar
19.
J Oleo Sci ; 68(7): 625-635, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31178462

RESUMO

The seed of five fruits and vegetables, which are often eaten by Chinese people, were selected as research objects to study the physicochemical properties, nutritional ingredients and antioxidant capacity of their seed oils. The fatty acid results indicated that the oleic acid was the main unsaturated fatty acid in almond oil and celery seed oil (content of 64.10% and 62.96%, respectively), and the wax gourd seed oil, watermelon seed oil and pumpkin seed oil were linoleic acid as the main unsaturated fatty acid (content of 72.45%, 76.77% and 47.35%, respectively). Unsaturated fatty acids are mainly located at the sn-2 position of the triacylglycerol (TAG), whereas saturated fatty acids are mainly located at the sn-1, 3 positions for the five seed oils. The pumpkin seed oil had certain advantages in terms of phytosterols and squalene (3716 and 2732 mg/kg, respectively). The high content of polyphenol for celery seed oil exhibits higher medicinal value. Polyphenols, and brassicasterols were have significant correlation with antioxidant capacity (p < 0.05, r = 0.890-0.998). The significant differences in nutrient composition between these fruits and vegetables seed oils indicate their unique value as food.


Assuntos
Antioxidantes , Frutas/química , Óleos Vegetais/química , Óleos Vegetais/farmacologia , Verduras/química , Fenômenos Químicos , China , Colestadienóis , Ácidos Graxos/análise , Ácidos Graxos/química , Ácidos Graxos/isolamento & purificação , Ácidos Graxos Insaturados/análise , Ácidos Graxos Insaturados/química , Ácidos Graxos Insaturados/isolamento & purificação , Ácidos Linoleicos/análise , Ácidos Linoleicos/isolamento & purificação , Ácido Oleico/análise , Ácido Oleico/isolamento & purificação , Fitosteróis , Polifenóis/análise , Polifenóis/isolamento & purificação , Esqualeno , Triglicerídeos/química
20.
Food Chem ; 297: 124926, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31253318

RESUMO

Sand was studied as a solid support in ultrasound-assisted matrix solid-phase dispersion (UA-MSPD) for the extraction of different pesticide classes, including organophosphates, carbamates, triazoles and pyrethroids from fruits and vegetables, with determination by GC-MS and LC-MS/MS. The performance of sand was compared with that of different types of classic solid supports and alternative natural materials from renewable sources. The best results were obtained using 0.5 g sample, 1 g sand as a solid support, 20 mg activated charcoal and 5 mL ethyl acetate as elution solvent. Recoveries ranged from 55 to 140% with an RSD ≤ 20%. LOQs varied from 0.005 to 0.5 mg kg-1 for all analytes. Thiamethoxam, captan, chlorpyrifos, dimethoate and pyrimethanil were found in strawberry samples at concentrations from 0.01 to 0.06 mg kg-1. Acephate and tebuconazole were found in a tomato sample at concentrations of 0.45 and 0.30 mg kg-1, respectively. The method developed was efficient, simple, cheap, robust, and environmentally friendly.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas , Resíduos de Praguicidas/análise , Extração em Fase Sólida/métodos , Verduras/química , Cromatografia Líquida de Alta Pressão , Dimetoato/química , Frutas/química , Frutas/metabolismo , Limite de Detecção , Resíduos de Praguicidas/isolamento & purificação , Piretrinas/química , Sonicação , Espectrometria de Massas em Tandem , Triazóis/química , Verduras/metabolismo
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