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1.
J Agric Food Chem ; 67(45): 12528-12537, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31631662

RESUMO

Seeds of 32 pure lines and 6 commercial broccoli cultivars were used to investigate variation in glucosinolates and their breakdown products. The aliphatic glucosinolate content was 54.5-218.7 µmol/g fresh weight, accounting for >90% of the total glucosinolates. The major glucosinolates found were glucoraphanin and glucoerucin in 27 samples and progoitrin in 7 samples. A gas chromatography-flame ionization detector (GC-FID) method was used to identify glucosinolate breakdown products; nine products were directly determined using standards. Using Arabidopsis thaliana lines myb28myb29 and Landsberg erecta to hydrolyze each reference glucosinolate, seven products were tentatively identified. 4-(Methylsulfinyl)butyl isothiocyanate and 5-(methylsulfinyl)pentanenitrile contents were 2.6-91.1 µmol/g fresh weight and 0-35.4 µmol/g fresh weight, respectively, with epithionitriles being more common than nitriles in accessions rich in alkenyl glucosinolate. Additionally, (S)-5-vinyl-1,3-oxazolidine-2-thione was detected in accessions rich in progoitrin. Specific lines with altered glucosinolate profiles and breakdown products were obtained and discussed according to the putative glucosinolate metabolism pathway.


Assuntos
Brassica/química , Glucosinolatos/química , Extratos Vegetais/química , Arabidopsis/química , Arabidopsis/metabolismo , Brassica/metabolismo , Glucosinolatos/metabolismo , Extratos Vegetais/metabolismo , Sementes/química , Sementes/metabolismo
2.
J Biochem ; 166(5): 441-448, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31504617

RESUMO

Glycosylinositol phosphoceramide (GIPC) is the most abundant sphingolipid in plants and fungi. Recently, we detected GIPC-specific phospholipase D (GIPC-PLD) activity in plants. Here, we found that GIPC-PLD activity in young cabbage leaves catalyzes transphosphatidylation. The available alcohol for this reaction is a primary alcohol with a chain length below C4. Neither secondary alcohol, tertiary alcohol, choline, serine nor glycerol serves as an acceptor for transphosphatidylation of GIPC-PLD. We also found that cabbage GIPC-PLD prefers GIPC containing two sugars. Neither inositol phosphoceramide, mannosylinositol phosphoceramide nor GIPC with three sugar chains served as substrate. GIPC-PLD will become a useful catalyst for modification of polar head group of sphingophospholipid.


Assuntos
Biocatálise , Brassica/enzimologia , Ceramidas/metabolismo , Inositol/metabolismo , Fosfatidilcolinas/metabolismo , Fosfolipase D/metabolismo , Folhas de Planta/enzimologia , Brassica/química , Ceramidas/química , Inositol/análogos & derivados , Inositol/química , Estrutura Molecular , Fosfatidilcolinas/química , Fosfolipase D/química , Folhas de Planta/química
4.
Bioelectrochemistry ; 130: 107348, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31437810

RESUMO

A practical electrochemical biosensor with high sensitivity was developed for detecting organophosphorus (OP). Initially, Ce metal was introduced into an UiO-66-template to form Ce/UiO-66. Later, graphene oxide (GO), carbon black (CB) and multi-walled carbon nanotubes (MWCNTs) were separately added to Ce/UiO-66 to compare the effect of different carbon-based material types on the performance of the biosensor. Exclusively, Ce/UiO-66/MWCNTs with a Ce (7%) and MWCNT (30%) matrix was found to not only load more acetylcholinesterase (AChE) onto vacant sites but also increase electron transfer and decrease the number of diffusion pathways between the thiocholine and electrode surface. Moreover, the appropriate oxophilicity of Ce coupled with the high surface area and good conductivity of MWCNTs in the UiO-66 structure revealed a high affinity to acetylthiocholine chloride (ATCl) and possible catalysis of the hydrolysis of ATCl with a Michaelis-Menten constant of 0.258 mM. This biosensor, under optimal conditions, demonstrated a rapid and sensitive detection of paraoxon over a wide linear range of 0.01-150 nM, with a low detection limit of 0.004 nM. As a result, the AChE/Ce/UiO-66/MWCNTs/GCE biosensor can be employed in laboratory and field experiments to determine paraoxon levels.


Assuntos
Técnicas Biossensoriais/métodos , Cério/química , Estruturas Metalorgânicas/química , Paraoxon/análise , Praguicidas/análise , Acetilcolinesterase/química , Animais , Brassica/química , Electrophorus , Enzimas Imobilizadas/química , Proteínas de Peixes/química , Grafite/química , Modelos Moleculares , Nanotubos de Carbono/química , Spinacia oleracea/química
5.
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
6.
Ultrason Sonochem ; 59: 104712, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31421620

RESUMO

In this study, the effect of sweep frequency ultrasound (SFUS), sodium hypochlorite (NaOCl) and their combinations (SFUS + NaOCl) in reducing and inhibiting natural microbiota as well as preserving quality of fresh-cut Chinese cabbage during storage (4 °C and 25 °C) for up to 7 days was investigated. In effect, 40 kHz sweep frequency ultrasound in combination with 100 mg/L sodium hypochlorite resulted in maximum reduction and inhibition of mesophilic counts, yeast and molds and minimum chlorophyll depletion, weight loss and electrolyte leakage. However, colour and textural characteristics deteriorated. The combined treatment suppressed the activities of polyphenol oxidase and peroxidase and manifested its preservative effect after Fourier Transform near-infrared spectroscopy analysis. Synergistic reductions were recorded in most of the combined treatments though largely <1.0 log CFU/g. Specifically, the combined treatment significantly (P < 0.05) reduced mesophilic counts by an added 2.7 log CFU/g, yeasts and molds by an added 2.0 log CFU/g when compared to the individual treatments. During storage at 4 and 25 °C, washing with SFUS + NaOCl produced Chinese cabbage with lower microbial counts, in comparison with the individual treatments. However, post-treatment storage could not entirely inhibit microbial survival as populations increased during storage even at refrigeration temperature of 4 °C. The results demonstrate that ultrasound and sodium hypochlorite are promising hurdle alternatives for the reduction and inhibition of microorganisms, as well as prolonging the shelf life and retaining the quality characteristics of Chinese cabbage.


Assuntos
Brassica/microbiologia , Qualidade dos Alimentos , Armazenamento de Alimentos/métodos , Microbiota , Ondas Ultrassônicas , Brassica/química , Brassica/efeitos dos fármacos , Clorofila/análise , Cor , Eletrólitos/análise , Viabilidade Microbiana/efeitos dos fármacos , Microbiota/efeitos dos fármacos , Cloreto de Sódio/farmacologia
7.
J Agric Food Chem ; 67(35): 9782-9788, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31390859

RESUMO

Sulforaphane, a potent antioxidant compound, is unstable at ambient temperature, whereas its precursor glucoraphanin is stable and metabolized to sulforaphane. Thus, we hypothesized that glucoraphanin-rich diet could effectively induce antioxidant enzyme activities and investigated the protective effects of long-term intake of a glucoraphanin-enriched kale (GEK) diet on skin aging in senescence-accelerated mouse prone 1 (SAMP1) mice. The senescence grading score was significantly lower after treatment with GEK for 39 weeks than that of the control mice. GEK also suppressed the thinning of the dorsal skin layer. Moreover, the GEK treatment enhanced the collagen production and increased the nuclear translocation of Nrf2 and HO-1 expression level in the skin tissue. TßRII and Smad3 expressions were clearly higher in the GEK-treated group than in the control group. Thus, GEK suppressed senescence in SAMP1 mice by enhancing the antioxidant activity and collagen production via the TßRII/Smad3 pathway, suggesting its practical applications for protection against skin aging.


Assuntos
Brassica/metabolismo , Glucosinolatos/metabolismo , Imidoésteres/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Extratos Vegetais/metabolismo , Receptor do Fator de Crescimento Transformador beta Tipo II/metabolismo , Envelhecimento da Pele/fisiologia , Proteína Smad3/metabolismo , Animais , Antioxidantes/metabolismo , Brassica/química , Colágeno/metabolismo , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Fator 2 Relacionado a NF-E2/genética , Receptor do Fator de Crescimento Transformador beta Tipo II/genética , Transdução de Sinais , Envelhecimento da Pele/genética , Proteína Smad3/genética , Fatores de Tempo
8.
J Sci Food Agric ; 99(15): 6998-7007, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31442313

RESUMO

BACKGROUND: Excessive or improper use of organophosphorus pesticides (OPPs) may adversely affect human health through the food chain. In the present study, a simple, rapid and effective analytical method was successfully established and used for the determination of OPPs quinalphos and its analogs in different food samples. RESULTS: Under the optimized experimental conditions, five OPPs (quinalphos, triazophos, parathion, fenthion and chlorpyrifos-methyl) exhibit a good linearity within a range of 0.02 to 2.0 µg mL-1 . The detection limit range was 3.0 to 10.0 µg L-1 (signal-to-noise ratio = 3). The method was successfully used to detect and quantify the residues of quinalphos and its analogs in tomato, cabbage, barley and water samples; all spiked samples gave satisfactory recovery rates for the target analytes of between 82% and 98%, with a relative SD of 3.6% to 7.8%. CONCLUSION: The results obtained show that the proposed method is an accurate, rapid and reliable sample pre-treatment method with respect to giving a good enrichment factor and detection limit for determining quinalphos pesticide residues in different food samples. © 2019 Society of Chemical Industry.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Contaminação de Alimentos/análise , Compostos Organofosforados/química , Compostos Organofosforados/isolamento & purificação , Resíduos de Praguicidas/química , Resíduos de Praguicidas/isolamento & purificação , Extração em Fase Sólida/métodos , Brassica/química , Hordeum/química , Limite de Detecção , Lycopersicon esculentum/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação
9.
Food Chem ; 301: 125301, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31387032

RESUMO

Novel delivery systems for epigallocatechin gallate (EGCG) were developed using broccoli by-products and their fractions as carriers. Puree and pomace from broccoli by-products had higher adsorption capacities for EGCG than juice at 25 °C (43.20 mg g-1, 39.47 mg g-1 and 25.22 mg g-1 dry weight for pomace, puree and juice respectively). Chemical sorption is the rate-controlling step for EGCG-broccoli interactions. Langmuir and Freundlich models well described the adsorption of EGCG onto puree and pomace. FTIR results indicated that EGCG-puree had stronger interaction than EGCG-pomace. When the same level of EGCG (∼26 mg) was added to different matrices, more EGCG (∼20%) was recovered from the in vitro digestion system of EGCG-loaded puree than from the EGCG-loaded pomace (14%) and neat EGCG (9%). The antioxidant capacity of the whole digesta was positively correlated with the EGCG levels. Broccoli by-products are promising carriers for delivering and stabilizing EGCG through gastrointestinal digestion.


Assuntos
Brassica/química , Catequina/análogos & derivados , Portadores de Fármacos/química , Adsorção , Antioxidantes/análise , Catequina/administração & dosagem , Catequina/química , Catequina/farmacocinética , Digestão , Sistemas de Liberação de Medicamentos/métodos , Espectroscopia de Infravermelho com Transformada de Fourier , Resíduos
10.
Food Chem ; 301: 125289, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31387047

RESUMO

Acylated anthocyanins, such as those found in red cabbage, are more heat-, light-, and alkaline pH-stable than non-acylated anthocyanins, making them attractive for a variety of commercial applications. A UPLC-DAD-MSE method with an optimized chromatographic strategy was used to identify 29 red cabbage anthocyanins, predominantly acylated and glucosylated cyanidin derivatives. Anthocyanin profiles of 27 red cabbage genotypes harvested in consecutive growing seasons were measured and assessed for variation. Three unique anthocyanin profile fingerprints were identified through hierarchical clustering analysis. PCA analysis identified anthocyanin accumulation traits and genotypes with high diversity which can be utilized in future investigations into the genetic and molecular basis for anthocyanin production, acylation, and diversity.


Assuntos
Antocianinas/análise , Brassica/química , Brassica/genética , Melhoramento Vegetal , Polimorfismo Genético , Estações do Ano , Acilação , Antocianinas/química , Brassica/metabolismo , Cromatografia Líquida de Alta Pressão , Genótipo , Espectrometria de Massas
12.
Environ Monit Assess ; 191(9): 569, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31418103

RESUMO

Microcystins (MCs) are toxic secondary metabolites produced by several cyanobacteria genera that have been implicated in human cancer cases and deaths. Human exposure routes include direct contact with contaminated water and the consumption of contaminated food. The present study investigated the presence of MCs in three commonly consumed vegetables at the point of sale in market places as a means of assessing the direct human health risk of buying vegetables. Overall, 53% of the vegetables obtained from different markets had levels of MCs that were higher than 1.00 µg/g. Amaranthus hybridus L. (smooth amaranth) had the highest MC concentration (4.79 µg/g) in samples obtained from Sabon Gari Market, while Lactuca sativa L. (garden lettuce) had the lowest concentration (0.17 µg/g) in samples obtained from Dan-Magaji Market. The highest total daily intake (TDI) of MCs by an adult weighing 60 kg was 3.19 µg/kg for A. hybridus, 1.41 µg/kg for Brassica oleracea L. (cabbage), and 2.94 µg/kg for L. sativa. The highest TDI of MCs for a child weighing 25 kg was highest in A. hybridus (1.91 µg/kg), followed by L. sativa (1.77 µg/kg). These results revealed that the consumption of vegetables sold in markets in Zaria, Nigeria, during the dry season represents a major exposure route to MCs. There is, therefore, an urgent need to develop policies and monitoring strategies to tackle this problem in developing countries.


Assuntos
Amaranthus/química , Brassica/química , Contaminação de Alimentos/análise , Alface/química , Microcistinas/análise , Humanos , Nigéria
13.
J Agric Food Chem ; 67(28): 7855-7868, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31274310

RESUMO

Bee pollen (BP) collected from different floras possesses various potential bioactivities, but the mechanism-related research on anti-inflammatory effects is limited. Here, three types of BP originating from Camellia sinensis L. (BP-Cs), Nelumbo nucifera Gaertn. (BP-Nn), and Brassica campestris L. (BP-Bc) were assessed using molecular and metabolomics methods to determine their anti-inflammatory effects. The differences in polyphenolic abundance of three types of BP extracts were determined by HPLC-DAD/Q-TOF-MS. In vitro anti-inflammatory effects of three BP extracts were evaluated in a lipopolysaccharide (LPS)-induced RAW 264.7 cells model. BP-Cs extract with the most abundant polyphenols was found to be the most effective in reducing inflammation by downregulating inflammatory-related genes expression and blocking the activation of MAPK and NF-κB signaling pathways. Polyphenol-rich BP-Cs was further evaluated for their in vivo anti-inflammatory effect in a LPS-induced acute lung injury mouse model. An UPLC-Q-TOF/MS-based metabolomics approach was applied to analyze metabolite changes in mouse serum. Weshowed that the pretreated BP-Cs extract alleviated inflammation and regulated glycerophospholipid metabolism significantly. Our findings provide a foundation for developing and justifying BP as a potential anti-inflammatory ingredient in functional foods or nutraceutical formulations.


Assuntos
Lesão Pulmonar Aguda/tratamento farmacológico , Anti-Inflamatórios/administração & dosagem , Extratos Vegetais/administração & dosagem , Pólen/química , Lesão Pulmonar Aguda/genética , Lesão Pulmonar Aguda/imunologia , Animais , Anti-Inflamatórios/química , Abelhas , Brassica/química , Camellia sinensis/química , Cromatografia Líquida de Alta Pressão , Humanos , Lipopolissacarídeos/efeitos adversos , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Masculino , Espectrometria de Massas , Camundongos , Camundongos Endogâmicos ICR , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Quinases de Proteína Quinase Ativadas por Mitógeno/imunologia , NF-kappa B/genética , NF-kappa B/imunologia , Nelumbo/química , Extratos Vegetais/química , Polifenóis/administração & dosagem , Polifenóis/química , Células RAW 264.7
14.
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
15.
Anal Bioanal Chem ; 411(23): 6057-6066, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31278555

RESUMO

In this study, we report a direct surface plasmon resonance (SPR) biosensor based on an oriented assembly of antibody for the rapid detection of chlorpyrifos residue in agricultural samples. In this covalent-orientated strategy, staphylococcal protein A (SPA) was first covalently bound to the surface for monitoring chlorpyrifos residue, with subsequent binding of the antibody in an orientated fashion via its fragment crystallizable (Fc) region. Consequently, the SPA-modified biosensor exhibited a satisfactory specificity and a low detection limit of 0.056 ng mL-1 for chlorpyrifos, with a linear detection range of 0.25-50.0 ng mL-1. Under optimal conditions, the sensor chip could be regenerated for at least 210 cycles. The results presented here indicate that the SPA-modified sensor chip can successfully improve the sensitivity and obviating the need of the modification of the antibody. The developed SPR biosensor method has the great potential for rapid, sensitive, and specific detection with broad applications in areas of environmental monitoring and food safety. Graphical abstract.


Assuntos
Clorpirifos/análise , Análise de Perigos e Pontos Críticos de Controle/métodos , Inseticidas/análise , Proteína Estafilocócica A/química , Ressonância de Plasmônio de Superfície/métodos , Anticorpos Imobilizados/química , Brassica/química , Contaminação de Alimentos/análise , Imunoensaio/métodos , Limite de Detecção , Malus/química , Zea mays/química
16.
J Agric Food Chem ; 67(32): 9096-9103, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31356079

RESUMO

A monoclonal antibody (mAb) was raised against tebuconazole (TEB) using a hapten where the p-chloro substituent of the TEB molecule was replaced with a long-chain carboxylic acid. The resulting mAb showed high sensitivity and specificity against TEB characterized by ELISA with a half-maximal inhibitory concentration (IC50) of 0.19 ng mL-1 and with cross-reactivity (CR) values below 0.01% to several analogues of triazole fungicides. On the basis of the mAb produced, a quantum dot beads-based fluorescence immunochromatographic test strip assay (QBs-FITSA) was developed for rapid and sensitive detection of TEB in agricultural product samples. The QBs-FITSA exhibited a linear detection range from 0.02 to 1.25 ng mL-1 with a limit of detection (LOD) of 0.02 ng mL-1. Furthermore, using produced mAb, multiple high-throughput rapid immunoassay formats could be achieved as a convenient monitoring tool for evaluation of human and environmental exposure to TEB.


Assuntos
Brassica/química , Cucumis sativus/química , Fungicidas Industriais/análise , Imunoensaio/métodos , Triazóis/análise , Triticum/química , Anticorpos Monoclonais/análise , Contaminação de Alimentos/análise , Fungicidas Industriais/isolamento & purificação , Imunoensaio/instrumentação , Limite de Detecção , Pontos Quânticos/química , Triazóis/isolamento & purificação
17.
Plant Mol Biol ; 101(1-2): 65-79, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31190320

RESUMO

KEY MESSAGE: Overexpression of BoMYB29 gene up-regulates the aliphatic glucosinolate pathway in Brassica oleracea plants increasing the production of the anti-cancer metabolite glucoraphanin, and the toxic and pungent sinigrin. Isothiocyanates, the bio-active hydrolysis products of glucosinolates, naturally produced by several Brassicaceae species, play an important role in human health and agriculture. This study aims at correlating the content of aliphatic glucosinolates to the expression of genes involved in their synthesis in Brassica oleracea, and perform functional analysis of BoMYB29 gene. To this purpose, three genotypes were used: a sprouting broccoli, a cabbage, and a wild genotype (Winspit), a high glucosinolate containing accession. Winspit showed the highest transcript level of BoMYB28, BoMYB29 and BoAOP2 genes, and BoAOP2 expression was positively correlated with that of the two MYB genes. Further analyses of the aliphatic glucosinolates also showed a positive correlation between the expression of BoAOP2 and the production of sinigrin and gluconapin in Winspit. The Winspit BoMYB29 CDS was cloned and overexpressed in Winspit and in the DH AG1012 line. Overexpressing Winspit plants produced higher quantities of alkenyl glucosinolates, such as sinigrin. Conversely, the DH AG1012 transformants showed a higher production of methylsulphinylalkyl glucosinolates, including glucoraphanin, and, despite an up-regulation of the aliphatic glucosinolate genes, no increase in alkenyl glucosinolates. The latter may be explained by the absence of a functional AOP2 gene in DH AG1012. Nevertheless, an extract of DH AG1012 lines overexpressing BoMYB29 provided a chemoprotective effect on human colon cells. This work exemplifies how the genetic diversity of B. oleracea may be used by breeders to select for higher expression of transcription factors for glucosinolate biosynthesis to improve its natural, health-promoting properties.


Assuntos
Brassica/genética , Glucosinolatos/metabolismo , Extratos Vegetais/farmacologia , Fatores de Transcrição/metabolismo , Brassica/química , Brassica/metabolismo , Expressão Gênica , Variação Genética , Células HT29 , Humanos , Imidoésteres/metabolismo , Isotiocianatos/metabolismo , Extratos Vegetais/química , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Fatores de Transcrição/genética
18.
Sensors (Basel) ; 19(11)2019 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-31146350

RESUMO

Monitoring plant nitrogen (N) in a timely way and accurately is critical for precision fertilization. The imaging technology based on visible light is relatively inexpensive and ubiquitous, and open-source analysis tools have proliferated. In this study, texture- and geometry-related phenotyping combined with color properties were investigated for their potential use in evaluating N in pakchoi (Brassica campestris ssp. chinensis L.). Potted pakchoi treated with four levels of N were cultivated in a greenhouse. Their top-view images were acquired using a camera at six growth stages. The corresponding plant N concentration was determined destructively. The quantitative relationships between the nitrogen nutrition index (NNI) and the image-based phenotyping features were established using the following algorithms: random forest (RF), support vector regression (SVR), and neural network (NN). The results showed the full model based on the color, texture, and geometry-related features outperforms the model based on only the color-related feature in predicting the NNI. The RF full model exhibited the most robust performance in both the seedling and harvest stages, reaching prediction accuracies of 0.823 and 0.943, respectively. The high prediction accuracy of the model allows for a low-cost, non-destructive monitoring of N in the field of precision crop management.


Assuntos
Brassica/química , Processamento de Imagem Assistida por Computador , Aprendizado de Máquina , Nitrogênio/análise , Algoritmos , Biomassa , Modelos Teóricos , Avaliação Nutricional , Fenótipo
19.
Environ Monit Assess ; 191(7): 417, 2019 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-31172293

RESUMO

Ingestion of leafy vegetables is an important dietary component of most Africans due to its health benefits. High levels of polycyclic aromatic hydrocarbons (PAHs) in the leafy vegetables may pose a significant health hazard to the consumers. Rose/Hibiscus, Chinese cabbage, lettuce, and garden egg leaves from farms along the Nima Creek, Accra, were selected. At each sampling site, the vegetable was uprooted and cut into leaves, stem, and root and analyzed differently. The GC-MS method was employed in the identification and quantification of 16 PAHs in the samples. The analysis was done at CSIR - Water Research Institute Organic Laboratory. The results obtained show concentrations of acenapththylene, acenapthene, benzo[a]anthracene, benzo[b]fluoranthene, and benzo[a]pyrene (except chrysene and pyrene which were found in garden egg leaves and Chinese cabbage respectively), while naphthalene was detected in all the vegetables. The mean concentration of phenanthrene in leaves, stem, and roots of Chinese cabbage vegetable varies according to the following order: roots (0.744 ± 0.16 µg/kg) ≥ leaves (0.598 ± 1.21 µg/kg) ≥ stem (0.327 ± 1.01 µg/kg). From the results of the isomeric ratios, the source of the PAHs in the leafy vegetables are from mixed sources, i.e., either pyrogenic and petrogenic origins. This calls for the formulation of stringent policies on the importation of over-age vehicles into the countries as well as on the indiscriminate burning of materials containing PAHs.


Assuntos
Brassica/química , Monitoramento Ambiental/métodos , Hibiscus/química , Alface/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Verduras/química , Acenaftenos/análise , Benzo(a)Antracenos/análise , Benzo(a)pireno/análise , Dieta , Fazendas , Fluorenos/análise , Inocuidade dos Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Gana , Naftalenos/análise , Fenantrenos/análise
20.
J Sci Food Agric ; 99(13): 5934-5945, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31206676

RESUMO

BACKGROUND: Package oxygen transmission rate (OTR) can affect the stability of natural color pigments such as anthocyanins, betalains and chlorophylls in foods during storage. In the present study, we investigated the oxygen sensitivity of selected pigments in thermally pasteurized vegetable purees held at a refrigeration temperature. We modulated the oxygen ingress in packaging using multilayer films with OTRs of 1, 30 and 81 cm3  m-2  day-1 . Red cabbage, beetroot and pea purees were vacuum packed, pasteurized to achieve a cumulative lethality of P 90 ° C 10 ° C = 12.8-13.4 min and stored at 7 °C for 80 days. RESULTS: Anthocyanins were relatively stable (< 4% losses), regardless of the film OTR. Betalains showed the highest sensitivity to different OTRs, with total losses varying from 4% to 49% at the end of storage and showing significant differences (P < 0.05) among the three films. Chlorophylls showed no significant difference (P > 0.05) in sensitivity to film OTRs. However, continuous degradation of chlorophylls was observed for all film types, with total chlorophyll losses ranging from 33% to 35%. Overall color differences (ΔE) at the end of storage for cabbage, beet and pea puree were between 0.50-1.70, 1.00-4.55 and 7.41-8.08, respectively. Betalains and chlorophylls degradation followed first-order and fractional conversion kinetics, whereas ΔE followed zero-order and fractional conversion kinetics during storage. CONCLUSION: All three pigments behaved differently to oxygen ingress during storage. Low to medium barrier films are suitable for products containing red cabbage anthocyanins. High barrier films are must for betalains, whereas medium to high barrier films are suitable for chlorophyll-containing products. © 2019 Society of Chemical Industry.


Assuntos
Antocianinas/química , Betalaínas/química , Clorofila/química , Produtos Vegetais/análise , Verduras/química , Beta vulgaris/química , Brassica/química , Cor , Armazenamento de Alimentos , Temperatura Alta , Oxirredução , Pasteurização , Ervilhas/química
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