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1.
J Food Sci ; 84(8): 2357-2363, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31364176

RESUMO

Peanut allergic consumers rely on food package labels to avoid foods containing peanut. The inadvertent presence of peanut in foods due to cross-contact can be fatal if ingestion of such food leads to an allergic reaction. Analytical methods are available to detect undeclared peanut in foods. However, depending on the type of food matrix and food processing parameters, method performance can be adversely affected due to reduction in the extraction efficiency of peanut proteins. Temperature and probe sonication were used as a preincubation treatment for peanut flour slurries to assess their effect on the total peanut protein solubility from raw, light-roasted, and dark-roasted peanut flours. The effect of these treatments on the immunoreactivity of peanut allergens (Ara h 1, Ara h 2, Ara h 3, and Ara h 6) was determined by an indirect enzyme-linked immunosorbent assay using antibodies raised against these individual peanut proteins. Preincubation at 50 °C did not significantly improve the peanut protein solubility, whereas an increase in protein solubility was observed when light- and dark-roasted peanut flour slurries were preincubated at 90 °C or sonicated. The immunoreactivity of peanut allergens varied depending on the degree of peanut flour roasting and type of preincubation treatment. Overall, the immunoreactivity of peanut allergens from most peanut flour slurries was unaffected when preincubated at 50 °C for up to 60 min or sonicated with a probe for up to 5 min, whereas preincubation at 90 °C resulted in a time-dependent reduction in immunoreactivity of peanut allergens. Sonication treatment may improve peanut protein extraction without markedly affecting their immunoreactivity. PRACTICAL APPLICATION: Extraction of peanut proteins is vital for developed analytical methods to estimate peanut allergens in foods. The manuscript describes the effect of two different temperatures (50 and 90 °C) and probe-type sonication on peanut protein solubility. The findings suggest sonication can improve peanut protein solubility without markedly affecting their immunoreactivity.


Assuntos
Arachis/imunologia , Antígenos de Plantas/análise , Antígenos de Plantas/imunologia , Antígenos de Plantas/isolamento & purificação , Arachis/química , Ensaio de Imunoadsorção Enzimática , Farinha/análise , Manipulação de Alimentos , Humanos , Proteínas de Plantas/análise , Proteínas de Plantas/imunologia , Proteínas de Plantas/isolamento & purificação , Temperatura Ambiente
2.
J Agric Food Chem ; 67(40): 11219-11229, 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31408330

RESUMO

Peanut allergy is a major health problem worldwide. Detection of food allergens is a critical aspect of food safety. The VHH domain of single chain antibody from camelids, also known as nanobody (Nb), showed its advantages in the development of biosensors because of its high stability, small molecular size, and ease of production. However, no nanobody specific to peanut allergens has been developed. In this study, we constructed a library with random triplets (NNK) in its CDR regions of a camel nanobody backbone. We screened the library with peanut allergy Ara h 3 and obtained several candidate nanobodies. One of the promising nanobodies, Nb16 was further biochemical characterization by gel filtration, isothermal titration calorimetry (ITC), cocrystallization, and Western blot in terms of its interaction with Ara h 3. Nb16 specifically binds to peanut major allergen Ara h 3 with a dissociation constant of 400 nM. Furthermore, we obtained the Ara h 3-Nb16 complex crystals. Structure analysis shows the packing mode is completely different between the Ara h 3-Nb16 complex crystal and the native Ara h 3 crystal. Structural determination of Ara h 3-Nb16 will provide the necessary information to understand the allergenicity of this important peanut allergen. The nanobody Nb16 may have application in the development of biosensors for peanut allergen detection.


Assuntos
Antígenos de Plantas/imunologia , Arachis/imunologia , Proteínas de Armazenamento de Sementes/imunologia , Anticorpos de Domínio Único/genética , Anticorpos de Domínio Único/imunologia , Sequência de Aminoácidos , Antígenos de Plantas/química , Antígenos de Plantas/genética , Arachis/química , Arachis/genética , Bacteriófagos/genética , Bacteriófagos/metabolismo , Western Blotting , Técnicas de Visualização da Superfície Celular , Proteínas de Armazenamento de Sementes/química , Proteínas de Armazenamento de Sementes/genética , Anticorpos de Domínio Único/análise
3.
J Agric Food Chem ; 67(38): 10713-10725, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31453702

RESUMO

Converting peanut protein biomass waste into environmentally friendly meat substitutes by a high-moisture extrusion process can help solve both resource and waste problems and be "double green". A multiscale method combined with some emerging techniques such as atomic force microscopy-based infrared spectroscopy and X-ray microscopy was used to make the whole extrusion process visible to show the process of forming a meat-like fibrous structure using two-dimensional and three-dimensional perspectives. The results showed that the protein molecules underwent dramatic structural changes and unfolded in the extruder barrel, which created favorable conditions for molecular rearrangement in the subsequent zones. It was confirmed that the meat-like fibrous structure started to form at the junction of the die and the cooling zone and that this structure was caused by the phase separation and rearrangement of protein molecules in the cooling zone. Moreover, the interactions between hydrogen bonds and disulfide bonds formed in the cooling zone maintained the meat-like fibrous structure with an α-helix > ß-sheet > ß-turn > random coil. Of the two main peanut proteins, arachin played a greater role in forming the fibrous structure than conarachin, especially those subunits of arachin with a molecular weight of 42, 39, and 22 kDa.


Assuntos
Arachis/química , Aromatizantes/química , Extratos Vegetais/química , Proteínas de Plantas/química , Resíduos/análise , Aromatizantes/isolamento & purificação , Química Verde , Ligações de Hidrogênio , Raios Infravermelhos , Extratos Vegetais/isolamento & purificação , Conformação Proteica
4.
Food Chem ; 299: 125025, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31295634

RESUMO

Peanut allergy is usually lifelong and accidental exposure impose formidable risk. The aim of this study was to assess the capacity of peanut proteins complexed to polyphenol extracts to reduce allergic response in C3H/HeJ mice. Mice were sensitized to peanut flour followed by exposure to amino acid diets fortified with peanut protein-polyphenol aggregates of either with low (15%; w/w) or high (40%; w/w) complexation ratios of blueberry (BB-Low and BB-High) and cranberry (CB-Low and CB-High) extracts. Treatment groups on diets with high complexation ratios of blueberry and cranberry aggregates showed significant reduction in peanut specific plasma Immunoglobulin E (IgE). Western blot analysis of spleen lysates showed CD63 protein expression was reduced in a dose-dependent manner in blueberry and cranberry complexed peanut protein supplemented diet groups. Our results demonstrate for the first time that complexation of polyphenols to peanut flour can potentially lower plasma IgE of peanut-sensitized C3H/HeJ mice.


Assuntos
Arachis/química , Arachis/imunologia , Imunoglobulina E/imunologia , Hipersensibilidade a Amendoim/prevenção & controle , Proteínas de Plantas/química , Proteínas de Plantas/imunologia , Polifenóis/química , Animais , Feminino , Camundongos , Camundongos Endogâmicos C3H , Especificidade da Espécie
5.
J Sci Food Agric ; 99(13): 5671-5679, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31150109

RESUMO

BACKGROUND: Aspergillus flavus is a major pollutant in moldy peanuts, and it has a large influence on the taste of food. The secondary metabolites of Aspergillus flavus, including aflatoxin B1 (AFB1) and aflatoxin B2 (AFB2), are highly toxic and can expose humans to high risk. The total mold count (TMC) is an important index to determine the contamination degree and hygiene quality of peanut. RESULTS: Quantitative calibration models were established based on full-band wavelengths and characteristic wavelengths, combined with chemometric methods, to explore the feasibility of the use of near-infrared spectroscopy (NIRS) for rapid detection of the TMC in peanuts. The successive projection algorithm (SPA) and elimination of uninformative variables (UVE) algorithms were used to extract the characteristic wavelengths. In comparison, the model built by original spectrum, selected with the UVE algorithm, gave the best result, with a correlation coefficient in a prediction set (RP ) of 0.9577, a root mean square error for the prediction set (RMSEP) of 0.2336 Log CFU/g, and a residual predictive deviation (RPD) of 3.5041. CONCLUSIONS: The results showed that NIRS is a rapid, practicable method for the quantitative detection of peanut Aspergillus flavus contamination. It is a promising method for detecting moldy peanuts and increasing peanut safety. © 2019 Society of Chemical Industry.


Assuntos
Arachis/microbiologia , Aspergillus flavus/isolamento & purificação , Contaminação de Alimentos/análise , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Algoritmos , Arachis/química , Aspergillus flavus/química , Aspergillus flavus/fisiologia
6.
Food Chem Toxicol ; 131: 110573, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31195070

RESUMO

This study was aimed at determining if oxidative stress imbalance in testes of rats occurs after n-butylparaben (n-ButP) exposure. Young male Sprague-Dawley rats were subcutaneously treated with n-ButP during one spermatogenic cycle (57 days) at 0 (control-oil), 150, 300 and 600 mg/kg/d with peanut oil as vehicle. A non-vehicle control group was also included. Antioxidant enzyme activities (superoxide dismutase, catalase, glutathione reductase, and glutathione peroxidase) and levels of reduced and oxidized glutathione were measured in testes. Lipid peroxidation and H2O2 concentrations were also assessed. Results showed an increase of oxidative stress in oil-treated groups, excepting 600 mg/kg/d, suggesting oxidative stress due to peanut oil. A possible antioxidant effect due to n-ButP and its metabolites was suggested at 600 mg/kg/d, the only group not showing oxidative stress. An increase of calcium concentration in testes was also observed. On the other hand, a physiologically-based pharmacokinetic (PBPK) model was developed and the concentrations of n-ButP and its metabolites were simulated in plasma and testes. The peak concentration (Cmax) in testes was found slightly higher than that in plasma. The current results indicate that peanut oil can cause oxidative stress while high doses of n-ButP can act as antioxidant agent in testes.


Assuntos
Disruptores Endócrinos/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Parabenos/toxicidade , Testículo/efeitos dos fármacos , Animais , Antioxidantes/farmacocinética , Antioxidantes/toxicidade , Arachis/química , Biomarcadores/metabolismo , Cálcio/metabolismo , Catalase/metabolismo , Disruptores Endócrinos/farmacocinética , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Redutase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Parabenos/farmacocinética , Óleo de Amendoim/toxicidade , Ratos Sprague-Dawley
7.
J Sci Food Agric ; 99(13): 5899-5909, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31225657

RESUMO

BACKGROUND: Most allelochemicals are secondary products released from root excretions or plant residues that accumulate in continuous cropping systems and cause severe decline in peanut yield. Resveratrol is a plant-derived stilbene that is released from peanut residues and accumulates in the soil; however, its allelopathic effects on peanut production are overlooked. Effective management solutions need to be developed to relieve allelopathy caused by soil resveratrol. Here, the biodegradation of resveratrol by the fungal endophyte Phomopsis liquidambari was investigated in a mineral salt medium and a soil trial. Resveratrol and its metabolites (produced by degradation by P. liquidambari) were detected by high-performance liquid chromatography-mass spectrometry (HPLC-MS). RESULTS: Resveratrol released from peanut residues reached a maximum concentration of 0.18 µg g-1 soil in litterbag experiments. Exogenous resveratrol inhibited peanut growth, nodule formation, and soil dehydrogenase activity, and reduced the soil microbial biomass carbon content and bacterial abundance, indicating an allelopathic role in peanut growth. More than 97% of the resveratrol was degraded within 72 and 168 h by P. liquidambari in pure culture and soil conditions, respectively. Resveratrol was first cleaved to 3,5-dihydroxybenzaldehyde and 4-hydroxybenzaldehyde, which were subsequently oxidized into 3,5-dihydroxybenzoic acid and 4-hydroxybenzoic acid, respectively. Fungal resveratrol cleavage oxygenase and the related gene expression were enhanced when P. liquidambari was induced by the resveratrol during the incubation. CONCLUSION: Our results indicate that the practical application of the fungal endophyte P. liquidambari has strong potential for biodegrading soil resveratrol, which can cause allelopathy in peanut continuous cropping systems. © 2019 Society of Chemical Industry.


Assuntos
Arachis/química , Ascomicetos/metabolismo , Endófitos/metabolismo , Feromônios/metabolismo , Resveratrol/metabolismo , Arachis/metabolismo , Arachis/microbiologia , Bactérias/classificação , Bactérias/efeitos dos fármacos , Bactérias/genética , Bactérias/isolamento & purificação , Biodegradação Ambiental , Feromônios/análise , Feromônios/farmacologia , Resveratrol/análise , Resveratrol/farmacologia , Solo/química , Microbiologia do Solo
8.
J Sci Food Agric ; 99(12): 5334-5340, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31038220

RESUMO

BACKGROUND: There are more than 30 peanut cultivars registered in Brazil. However, there are no published data about the content of nutrients and antinutrients even in the most commercially important ones. Therefore, our objective was to characterize commercial peanut cultivars harvested in Brazil by determining proximate and fatty acid composition and content of selected minerals and phytates, saponins and condensed tannins. RESULTS: Significant variations were found among the cultivars for almost all studied nutrients, except Mg. Granoleico and IAC 505 were identified as high oleic. Results were compared with data from the Brazilian Food Composition Table (TACO) and, for this, percentage differences (D%) were calculated. Appreciable D% were found for proteins, lipids, ash, dietary fiber, almost all fatty acids (except 20:0) and almost all studied minerals (except zinc). Moreover, remarkable variations in content of antinutrients were observed. IAC Red Tatu had the highest content of saponins; IAC OL3 and IAC 886 had the highest amounts of phytates; and IAC 886 had the highest amounts of condensed tannins. CONCLUSION: Results confirm the relevance of differentiating cultivars in the market and in national food composition tables and databases. Furthermore, some of these cultivars may be indicated for new use trends. © 2019 Society of Chemical Industry.


Assuntos
Arachis/química , Sementes/química , Arachis/classificação , Arachis/crescimento & desenvolvimento , Brasil , Fibras na Dieta/análise , Ácidos Graxos/análise , Minerais/análise , Nutrientes/análise , Valor Nutritivo , Ácido Fítico/análise , Proteínas de Plantas/análise , Sementes/crescimento & desenvolvimento
9.
J Agric Food Chem ; 67(22): 6212-6221, 2019 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-31099566

RESUMO

Common soil fungi, Aspergillus flavus and Aspergillus parasiticus, are opportunistic pathogens that invade preharvest peanut seeds. These fungi often produce carcinogenic aflatoxins that pose a threat to human and animal health through food chains and cause significant economic losses worldwide. Detection of aflatoxins and further processing of crops are mandated to ensure that contaminated agricultural products do not enter food channels. Under favorable conditions, the fungus-challenged peanut seeds produce phytoalexins, structurally related stilbenoids, capable of retarding fungal development. The purpose of the present study was to evaluate the potential influence of peanut phytoalexins on fungal development and aflatoxin formation in the course of peanut-fungus interaction. The present research revealed that during such interaction, aflatoxin formation was completely suppressed in A. flavus and A. parasiticus strains tested, when low concentrations of spores were introduced to wounded preincubated peanuts. In most of the experiments, when fungal spore concentrations were 2 orders of magnitude higher, the spores germinated and produced aflatoxins. Of all experimental seeds that showed fungal growth, 57.7% were aflatoxin-free after 72 h of incubation. The research provided new knowledge on the aflatoxin/phytoalexin formation in the course of peanut-fungus interaction.


Assuntos
Aflatoxinas/biossíntese , Arachis/microbiologia , Aspergillus/metabolismo , Sementes/química , Estilbenos/farmacologia , Arachis/química , Arachis/metabolismo , Aspergillus/efeitos dos fármacos , Aspergillus/crescimento & desenvolvimento , Interações Hospedeiro-Parasita , Doenças das Plantas/microbiologia , Sementes/metabolismo , Sementes/microbiologia , Sesquiterpenos/metabolismo , Sesquiterpenos/farmacologia , Esporos Fúngicos/efeitos dos fármacos , Esporos Fúngicos/crescimento & desenvolvimento , Esporos Fúngicos/metabolismo , Estilbenos/metabolismo
10.
J Food Sci ; 84(6): 1554-1562, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31116884

RESUMO

Although sensory appeal influences peanut consumption, peanut varieties are mostly selected based on agronomic traits. As a result, the sensory properties of peanut varieties, especially in southern Africa, are not known. Therefore, the primary objective of the study was to determine the sensory properties of the Malawi peanut varieties and the volatile compounds associated with roasted peanut flavor. Six dominant Malawi peanut varieties (Chalimbana, CG7, Nsinjiro, Kakoma, Baka, and Chitala) were evaluated in this study. All peanut samples were shelled and then, roasted in a convection oven to reach medium doneness as indicated by the surface color lightness (L) value of approximately 50. A hybrid descriptive analysis (DA) was done to determine the sensory profile of the roasted peanuts. Volatile compounds were extracted from equilibrated ground peanut sample using headspace-solid phase microextraction technique and analyzed by GC-MS. Analysis of Variance (ANOVA) of the DA data showed significant differences (P < 0.05) in the sensory profiles of the peanut varieties. Nsinjiro and Baka had a significantly higher intensity of roasted peanutty aroma and flavor (P < 0.05). The GC-MS results showed that pyrazines and furans were the dominant volatile compounds but, their respective concentrations, in the evaluated peanut varieties, were significantly different (P < 0.05). Among the pyrazines, 2-ethyl-3,5-dimethyl pyrazine was strongly correlated with roasted peanutty flavor (r = 0.927) just like 2,5 dimethyl pyrazine (r = 0.916). Therefore, 2-ethyl-3,5-dimethyl pyrazine and 2,5-dimethyl pyrazine production pathways could provide more insights into the origins of roasted peanut flavor. PRACTICAL APPLICATION: The findings of this study can help food product developers, who have no access to sensory and analytical analyses, to identify Malawi peanut varieties that are suitable for various food applications. Furthermore, plant breeders could also use the findings to inform new projects aimed at improving the sensory properties of the peanut varieties.


Assuntos
Arachis/química , Aromatizantes/química , Arachis/classificação , Cor , Culinária , Aromatizantes/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Malaui , Odorantes/análise , Microextração em Fase Sólida , Paladar , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/isolamento & purificação
11.
J Food Sci ; 84(6): 1570-1576, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31120576

RESUMO

This study evaluated effects of green compared with brown coating colors and varying levels of hydrolyzed squid peptide powder (HSP) on seafood flavor perception, sensory liking, emotions, and purchase intent (PI) of coated peanuts. Dried squid head was enzymatically hydrolyzed to produce HSP, which was then incorporated into peanut coating material at 0%, 0.89%, 1.78%, and 2.66% levels. Green-coated peanuts (GCP) and brown-coated peanuts (BCP) were produced and tested with U.S. consumers. A 2-AC test (N = 100 consumers) was used to determine effects of coating colors on expected/perceived seafood flavor intensity of GCP compared with BCP at an equal HSP level based separately on looking, smelling, and tasting. Only tasting produced perceptual differences, at 1.78% and 2.66% HSP, with stronger seafood flavor intensity observed for GCP. Consumer testing (N = 160) yielded low mean seafood aroma liking scores for BCP (4.04) and GCP (4.13) at 2.66% HSP. The emotion "disgusted" was most affected by HSP addition for GCP. Presenting consumers with health benefit information (HBI) increased positive PI from 62.5% to 81.25% for BCP at 1.78% HSP, which had higher mean overall liking scores (6.05 before HBI, 6.24 after HBI) than 2.66% HSP samples. Overall liking was a significant predictor for positive PI with odds ratios of 1.52 to 2.20. Overall, green color and HSP addition levels of the coating inserted negative effects on liking, emotion, and PI of coated peanuts. This study demonstrated that HSP made from byproduct of squid processing could be successfully incorporated into coated peanuts, supporting the concept of sustainability of food supply. PRACTICAL APPLICATION: In this study, the functional peptide ingredient made from squid head, a byproduct from seafood industry, was incorporated into coated peanuts. Effects of different coating colors (green compared with brown) and varying levels of hydrolyzed squid peptide powder on consumers' seafood flavor perception, liking, emotions, and purchase intent of seasoned coated peanuts were clearly observed. The color of the coating material played an important visual cue that influenced product liking. Presenting consumers with health benefit information increased overall liking and positive purchase intent of the samples. Multisensory interactions of color and seafood aroma/flavor in these products should be further optimized.


Assuntos
Arachis/química , Comportamento do Consumidor/economia , Decapodiformes/química , Peptídeos/química , Percepção Gustatória , Adulto , Animais , Cor , Emoções , Feminino , Aromatizantes/química , Manipulação de Alimentos , Humanos , Intenção , Masculino , Pessoa de Meia-Idade , Odorantes , Pós/química , Olfato , Adulto Jovem
12.
J Food Sci ; 84(6): 1529-1537, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31131890

RESUMO

This study aims to assess the enhancement of the chemical and sensory properties of roasted peanuts during storage, through the application of high-protein defatted peanut flour (DPF) coatings incorporated with and without antioxidants. The control sample without coating, packed in normal atmosphere (control), showed the highest conjugated dienes (CD) increment (from 1.17 on day 0 to 3.60 on day 180). Roasted peanuts without coating, packed in high barrier bags under vacuum, reached the lowest CD at day 180 (1.92). Conjugated trienes and peroxide values were analogous to CD. The control exhibited the greatest decrease in α-tocopherol (from 27.65 mg/100 g on day 0 to 21.32 mg/100 g on day 180) and γ-tocopherol (from 21.91 mg/100 g on day 0 to 14.99 mg/100 g on day 180). 3-Methylpyridine and 2,5-dimethylpyrazine decreased with storage time only for the control, which had the highest increase in oxidized flavor (from 0 on day 0 to 13.30 on day 180), cardboard (from 7.67 on day 0 to 15.23 on day 180), and astringency. The lowest decreases in roasted peanutty scores were seen in coated samples. DPF coatings delayed roasted peanuts oxidation, enhancing their sensory properties and shelf life compared with the control sample. PRACTICAL APPLICATION: Defatted peanut flour (DPF) is a byproduct obtained during peanut oil extraction and is a possible material for edible film preparation. This strategy adds value to the peanut industry by transforming a by-product into a material with the potential to develop biodegradable and economical films. The application of this DPF-based edible coating on the surface of roasted peanuts may have contributed to extent product's shelf life, allowing for coated products to be packaged in lower barrier and less expensive materials. Use of peanut material to coat peanuts avoids the risk of allergen protein cross contamination, which would be highly valuable for the food industry.


Assuntos
Arachis/química , Culinária/métodos , Sementes/química , Antioxidantes/química , Temperatura Alta , Humanos , Oxirredução , Peróxidos/análise , Paladar , alfa-Tocoferol/análise
13.
J Agric Food Chem ; 67(26): 7475-7484, 2019 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-31117490

RESUMO

Chia seeds are becoming increasingly common in Europe because of their functional and nutritional properties. Despite this, few studies have focused on the allergic potential and antibody cross-reactivity among storage proteins in chia seed and other plants. The aim of this study was to identify chia seed's immunoglobulin G (IgG) and immunoglobulin E (IgE) binding proteins ( Salvia hispanica L.) and to investigate the antibody cross-reactivity among its storage proteins and those of other seeds. Extracted chia seed proteins were separated by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Immunodetection was performed with commercial antibodies against sesame seed, hazelnut, and peanut and sera from 33 patients with a hazelnut allergy and five with a sesame allergy. Cross-reactivity of certain antibodies with storage proteins of chia seed, sesame seed, and hazelnut was assessed using an enzyme-linked immunosorbent assay (ELISA) inhibition, blot inhibition, and surface plasmon resonance (SPR) spectroscopy. IgG binding proteins were identified at molecular weight (MW) 70, 49, 34, 23, and 20 kDa by applying commercial antibodies. Furthermore, the interaction of chia proteins with sera from sesame-allergic patients led to identify IgE binding proteins at MW 49, 45, 31, 20, and 12 kDa, while IgEs in sera from hazelnut-allergic patients reacted with proteins at MW 300, 140, 49, 45, 31, 20, and 6 kDa. The results of ELISA inhibition and blot inhibition indicated chia seed proteins are similar to sesame seed and hazelnut proteins in the primary structure. The antisesame antibodies' binding to sesame proteins was more strongly inhibited by the chia globulin fraction (GLO) than the antihazelnut antibodies' binding to hazelnut proteins. SPR results confirmed the presence of IgG binding proteins in GLO and the high similarity of epitopes on globulins of chia seed and sesame seed. Thus, chia seed consumption might lead to cross-sensitization in patients with a sesame allergy.


Assuntos
Antígenos de Plantas/imunologia , Arachis/imunologia , Corylus/imunologia , Imunoglobulina E/imunologia , Imunoglobulina G/imunologia , Proteínas de Plantas/imunologia , Salvia/imunologia , Sementes/imunologia , Sesamum/imunologia , Arachis/química , Corylus/química , Reações Cruzadas , Eletroforese em Gel de Poliacrilamida , Hipersensibilidade Alimentar/imunologia , Humanos , Salvia/química , Sementes/química , Sesamum/química
14.
Environ Sci Pollut Res Int ; 26(18): 18624-18635, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31055751

RESUMO

Contamination of surface water and groundwater streams with carcinogenic chemicals such as arsenic (As) has been a major environmental issue worldwide, and requires significant attention to develop new and low-cost sorbents to treat As-polluted water. In the current study, arsenite (As(III)) and arsenate (As(V)) removal efficiency of peanut shell biochar (PSB) was compared with peanut shell (PS) in aqueous solutions. Sorption experiments showed that PSB possessed relatively higher As removal efficiency than PS, with 95% As(III) (at pH 7.2) and 99% As(V) (at pH 6.2) with 0.6 g L-1 sorbent dose, 5 mg L-1 initial As concentration, and 2 h equilibrium time. Experimental data followed a pseudo-second-order model for sorption kinetics showing the dominance of chemical interactions (surface complexation) between As and surface functional groups. The Langmuir model for sorption isotherm indicated that As was sorbed via a monolayer sorption process. The X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FTIR) spectroscopy analyses revealed that the hydroxyl (-OH) and aromatic surface functional (C=O, C=C-C, and -C-H) groups contributed significantly in the sorption of both As species from aqueous solutions through surface complexation and/or electrostatic reactions. We demonstrate that the pyrolysis of abandoned PS yields a novel, low-cost, and efficient biochar which provides dual benefits of As-rich water treatment and a value-added sustainable strategy for solid waste disposal.


Assuntos
Arachis/química , Arsênico/isolamento & purificação , Carvão Vegetal/química , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Adsorção , Arsênico/química , Conservação dos Recursos Naturais , Concentração de Íons de Hidrogênio , Cinética , Propriedades de Superfície , Poluentes Químicos da Água/química
15.
Food Chem ; 292: 32-38, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31054681

RESUMO

The effect of heat on extractability and immunoreactivity of proteins from roasted peanut flours and whole peanuts was evaluated using two general protein assays and six commercial peanut ELISA kits, respectively. The highest amount of protein was recovered from roasted peanuts with all ELISAs, while recovery showed a decrease with increasing levels of roasting of the peanut flours. Only the Morinaga kit showed sufficient sensitivity to detect peanut at low concentrations of the dark roast peanut flours. Both the protein and immunoassays indicated a decrease in protein solubility with roasting. The underestimation by immunoassays is a combination of decreased solubility and heat induced changes in the proteins that are being targeted by the ELISA antibodies. These findings suggest that most commercial ELISA kits may not reliably quantify peanut present in dark roast peanut flours at ≤25 ppm.


Assuntos
Arachis , Ensaio de Imunoadsorção Enzimática/métodos , Farinha , Análise de Alimentos/métodos , Proteínas de Plantas/análise , Arachis/química , Arachis/imunologia , Farinha/análise , Manipulação de Alimentos , Temperatura Alta , Proteínas de Plantas/imunologia , Sensibilidade e Especificidade , Solubilidade
16.
Water Sci Technol ; 79(7): 1367-1375, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31123236

RESUMO

Today, dyes are one of the major problematic pollutants in the environment and are broadly used in several industrial sectors. In the current research work, decolorization of safranin (basic dye) from aqueous solution was investigated using iron-impregnated peanut shell ash (Fe-PSA) as a catalyst in the UV-assisted heterogeneous Fenton process (Fe-PSA/H2O2/UV). The effect of parameters such as H2O2 concentration, catalyst dose, pH, initial dye concentration, temperature, and agitation speed was studied. The maximum decolorization of safranin was achieved at optimum parametric values of reagent dose = 8 mM, catalyst dose = 0.5 g, pH = 3, initial concentration of safranin = 50 ppm, temperature = 25 °C, and agitation speed = 200 rpm. The results revealed the efficient performance of Fe-PSA as catalyst in the Fe-PSA/H2O2/UV process for safranin treatment.


Assuntos
Fenazinas/química , Poluentes Químicos da Água/química , Arachis/química , Catálise , Peróxido de Hidrogênio/química , Concentração de Íons de Hidrogênio , Ferro , Fenazinas/análise , Poluentes Químicos da Água/análise
17.
Talanta ; 201: 52-57, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31122460

RESUMO

More and more attention about food safety leads to a research hotspot to develop new detection methods for food contaminant. To address the problems of serious interference and low sensitivity, a chemiluminescent aptasensor for the detection of aflatoxin B1(AFB1) in food was developed in this paper. It is based on horseradish peroxidase (HRP) catalyze the luminol chemiluminescence reaction. The hybridization chain reaction (HCR) signal amplification strategy has been used to improve the detection sensitivity. Magnetic separation could further reduce background signal obviously at the same time. AFB1 as a model of analyte to test the capability of our developed assay system. Under the optimal experimental conditions, CL intensity showed a good linear correlation with the concentrations of AFB1 ranging from 0.5 to 40 ng mL-1. The limit of detection was estimated 0.2 ng mL-1 based on 3 times of the signal-to-noise ratio which is lower than those of the previously reported sensors. It could be used to detect AFB1 content in real samples, such as peanuts and milk which were purchased in local supermarket. The results proved that the sensing system has good anti-interference and selectivity. In all, it has potential for practical application in food safety field.


Assuntos
Aflatoxina B1/análise , Aptâmeros de Nucleotídeos/química , Arachis/química , Técnicas Biossensoriais/métodos , Contaminação de Alimentos/análise , Leite/química , Animais , Aptâmeros de Nucleotídeos/genética , Armoracia/enzimologia , DNA/química , DNA/genética , Peroxidase do Rábano Silvestre/química , Peróxido de Hidrogênio/química , Limite de Detecção , Luminescência , Medições Luminescentes , Luminol/química , Hibridização de Ácido Nucleico , Oxirredução
18.
Biosens Bioelectron ; 134: 42-48, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30954925

RESUMO

A simple "signal-on" photoelectrochemical (PEC) aptasensor is constructed for Aflatoxin B1 (AFB1) detection based on electrochemically reduced graphene oxide/poly(5-formylindole)/Au (erGO/P5FIn/Au) nanocomposites. The nanocomposites are synthesized by simple electrochemical deposition method and show good photoelectrochemical performance. Poly(5-formylindole) (P5FIn) can generate electron-hole pairs under light irradiation, leading to the formation of robust cathode photocurrent. Au can be acted as signal amplifier due to the high conductivity. The erGO is used to immobilize AFB1 aptamer chain by π-π stacking interaction between the carbon six-membered ring in graphene and the C-N heterocyclic ring in nucleobases of ssDNA. After the insulating AFB1 aptamer chain is fixed to the electrode, the signal of PEC sensor is "OFF". In the process of AFB1 detection, the aptamer chain detaches from the surface of erGO, which results in "ON" of the sensor signal. Based on this design, this constructed PEC aptasensor shows a high sensitivity for AFB1 with a wide linear detection range (LDR) from 0.01 ng mL-1 to 100 ng mL-1. The limit of detection (LOD) is 0.002 ng mL-1. This PEC sensor also exhibits good stability, selectivity, specificity, and satisfactory practical sample analysis ability. This work may provide a new promising PEC platform for AFB1 detection as well as some other small molecules analysis.


Assuntos
Aflatoxina B1/análise , Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/instrumentação , Análise de Alimentos/instrumentação , Ouro/química , Grafite/química , Nanocompostos/química , Arachis/química , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Desenho de Equipamento , Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Indóis/química , Limite de Detecção , Oxirredução , Processos Fotoquímicos , Polímeros/química
19.
Phytother Res ; 33(5): 1490-1500, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30883927

RESUMO

Improvement of bone formation is necessary for successful treatment of the bone defects associated with osteoporosis. In this study, we sought to elucidate the osteogenic activity of peanut sprouts and their bioactive components. We found that peanut sprout water extract (PSWE) enhanced bone morphogenetic protein-2-mediated osteoblast differentiation in a dose-dependent manner by stimulating expression of runt-related transcription factor 2 (Runx2) via activation of AKT/MAP kinases. We identified a major component of PSWE, soyasaponin Bb, as the bioactive compound responsible for improvement of anabolic activity. Soyasaponin Bb from PSWE enhanced expression of the osteogenic transcription factor Runx2 and alkaline phosphatase. The soyasaponin Bb content depended on sprouting time of peanut, and the anabolic action of PSWE was dependent on soyasaponin Bb content. Thus, PSWE and soyasaponin Bb have the potential to protect against bone disorders, including osteoporosis.


Assuntos
Arachis/química , Proteínas Morfogenéticas Ósseas/metabolismo , Osteoblastos/metabolismo , Osteogênese/fisiologia , Osteoporose/dietoterapia , Saponinas/metabolismo , Plântula/química , Diferenciação Celular , Proliferação de Células , Osteoporose/patologia , Fatores de Transcrição
20.
Int J Mol Sci ; 20(5)2019 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-30862029

RESUMO

Peanut sprouts (PS), which are germinated peanut seeds, have recently been reported to have anti-oxidant, anti-inflammatory, and anti-obesity effects. However, the underlying mechanisms by which PS modulates lipid metabolism are largely unknown. To address this question, serial doses of PS extract (PSE) were added to 3T3-L1 cells during adipocyte differentiation. PSE (25 µg/mL) significantly attenuated adipogenesis by inhibiting lipid accumulation in addition to reducing the level of adipogenic protein and gene expression with the activation of AMP-activated protein kinase (AMPK). Other adipocyte cell models such as mouse embryonic fibroblasts C3H10T1/2 and primary adipocytes also confirmed the anti-adipogenic properties of PSE. Next, we investigated whether PSE attenuated lipid accumulation in mature adipocytes. We found that PSE significantly suppressed lipogenic gene expression, while fatty acid (FA) oxidation genes were upregulated. Augmentation of FA oxidation by PSE in mature 3T3-L1 adipocytes was confirmed via a radiolabeled-FA oxidation rate experiment by measuring the conversion of [³H]-oleic acid (OA) to [³H]-H2O. Furthermore, PSE enhanced the mitochondrial oxygen consumption rate (OCR), especially maximal respiration, and beige adipocyte formation in adipocytes. In summary, PSE was effective in reducing lipid accumulation in 3T3-L1 adipocytes through mitochondrial fatty acid oxidation involved in AMPK and mitochondrial activation.


Assuntos
Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Arachis/química , Ácidos Graxos/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Oxirredução , Extratos Vegetais/farmacologia , Triglicerídeos/metabolismo , Células 3T3-L1 , Proteínas Quinases Ativadas por AMP/metabolismo , Adipogenia/efeitos dos fármacos , Animais , Respiração Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/metabolismo , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Flavonoides/química , Metabolismo dos Lipídeos/efeitos dos fármacos , Camundongos , Consumo de Oxigênio , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Polifenóis/química , Resveratrol/química
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