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1.
Food Funct ; 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31608342

RESUMO

Epidemiological studies have shown that exposure to ambient fine particulate matter (PM2.5) is associated with an increased risk for cardiopulmonary diseases. The MEK5/ERK5 and NF-κB signaling pathways are closely related to the regulation of acute pulmonary cell injury (APCI) and may play an important role in the underlying pathophysiological mechanisms. Related studies have shown that Biochanin A (BCA) effectively interferes with APCI, but the underlying mechanism through which this occurs is not fully understood. Previously, based on proteomic and bioinformatic research, we found the indispensable role of MEK5 in mediating remission effects of BCA against PM2.5-induced lung toxicity. Therefore, using A549 adenocarcinoma human alveolar basal epithelial cells (A549 cells), we combined western blot and qRT-PCR to study the protective signaling pathways induced by BCA, indicating that MEK5/ERK5 and NF-κB are both involved in mediating APCI in response to PM2.5, and MEK5/ERK5 positively activated NF-κB and its downstream cellular regulatory factors. BCA significantly suppressed PM2.5-induced upregulation of MEK5/ERK5 expression and phosphorylation and activation of NF-κB. Furthermore, due to the specificity of the MEK5/ERK5 protein structure, the binding sites and binding patterns of BCA and MEK5 were analyzed using molecular docking correlation techniques, which showed that there are stable hydrogen bonds between BCA and the PB1 domain of MEK5 as well as its kinase domain. BCA forms a stable complex with MEK5, which has potential effects on MEKK2/3-MEK5-ERK5 ternary interactions, p62/αPKC-mediated NF-κB regulation, and inhibition of MEK5 target protein phosphorylation. Therefore, our study suggests that MEK5 is an important regulator of intracellular signaling of APCI in response to PM2.5 exposure. BCA may exert anti-APCI activity by targeting MEK5 to inhibit activation of the MEK5/ERK5/NF-κB signaling pathway.

2.
Food Chem ; 298: 125019, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31260984

RESUMO

This study aims to investigate the postharvest physiology and texture of garlic cloves packaged in polyethylene terephthalate (PET), polyethylene (PE), aluminized kraft paper (AKP), single kraft paper (SKP), and mesh bag. Germination rate, electrical conductivity, respiration intensity, water content, and texture were determined during 180 d storage at -2 °C. Results showed that the germination of garlic cloves packaged in PET, PE, and AKP was effectively inhibited during storage. PE effectively reduced the degree of damage to the cell membranes of the garlic cloves. PE and SKP significantly inhibited respiratory intensity during storage. Garlic cloves water content did not change significantly in 90 d storage which packaged in PE and SKP. PE exhibited better effect on the texture and freshness of garlic cloves than the other materials. In conclusion, PE is the best packaging material for maintaining the quality attributes and extending the shelf lives of garlic cloves.


Assuntos
Embalagem de Alimentos , Alho/fisiologia , Polietileno , Condutividade Elétrica , Armazenamento de Alimentos , Germinação , Polietilenotereftalatos , Refrigeração , Água/análise
3.
J Food Biochem ; 43(7): e12871, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31353726

RESUMO

Garlic has attracted considerable attention because of its bactericidal and anticancer effects. However, the greening of garlic purees greatly affects the product quality. This study investigated the influence of light colors and power on the greening of garlic, and determined the key substances of garlic puree greening, including γ-glutamyl transpeptidase (γ-GT), thiosulfinate, and alliinase. Results showed that purple light source greatly affects greening power, γ-GT, and thiosulfinate. Illumination using a 3-W power lamp could reduce the production of thiosulfinate and alliinase and inhibit the green transformation reaction. Illumination using a 5-W power lamp greatly affected the thiosulfinate content and greening power, whereas that using a 7-W power lamp greatly influenced the γ-GT activity, porphobilinogen content, and alliinase content. Results showed that the green color of garlic puree is greatly affected by the illumination color and intensity, which provides theoretical support for the anti-greening of light garlic puree. PRACTICAL APPLICATION: Because garlic puree easily turns green during processing, which affects the product quality and economic value, this study uses controllable light source radiation to influence the greening of garlic puree, hoping to delay or even solve this problem and provide a new simple method to prevent garlic puree from turning greening.

4.
Anal Chim Acta ; 1069: 1-27, 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31084735

RESUMO

Aflatoxin B1(AFB1) is one of the most toxic mycotoxins produced by fungi and results in inevitable contamination of food and feed at very low concentrations. Therefore, there is an urgent need to implement selective, sensitive and highly convenient methods for the determination of aflatoxin B1. Among these methods, the progress of nanomaterials, owing to their high performances and versatile properties, offers great prospects for realizing highly sensitive, selective and simple detection of AFB1, overcoming the restrictions of traditional methods such as process-complicated, time-consuming, labor-intensive and instruments-expensive. Many nanomaterials have been used for the immobilization of biomolecules as signal generators or fluorescent quenchers or for signal amplification in AFB1 detection. This review highlights recent progress that has been made in the development of nanoparticle-based assays and focuses on the analytical potential of nanomaterials, such as Au/Ag nanoparticles (Au/Ag NPs), carbon-based nanoparticles (CBNs), magnetic nanoparticles (MNPs), Quantum dots (QDs) and novel nanomaterials, including up-conversion nanoparticles (UCNPs), metal-organic frameworks (MOFs) and nanomaterial-functional DNA intelligent hydrogels, as well as hybrid nanostructures. The determination of AFB1 is divided into three aspects: sample pretreatment prior to AFB1 detection, immunoassays and biosensors. The details of the detection methods and their application principles are described, and the challenges and opportunities in the field of food analysis are described.


Assuntos
Aflatoxina B1/análise , Contaminação de Alimentos/análise , Nanoestruturas/química , Nanotecnologia , Animais , Técnicas Biossensoriais , Humanos , Imunoensaio
5.
Int J Biol Macromol ; 126: 917-925, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30578906

RESUMO

In this study, the chitosan, chitosan/nano-TiO2 and chitosan/nano-SiO2 coating films were prepared, their physico-chemical properties were determined. Then the preservation of Ginkgo biloba seeds coating with these films were investigated during storage. The incorporation of nano-TiO2 and nano-SiO2 particles of the best formula enhanced the mechanical properties of the composite films, which improved the water-vapor and gas permeability. Chitosan coating incorporation of nano-TiO2 and nano-SiO2 particles could significantly decrease the decay rate, shrinkage rate, respiration rate, ethylene production rate, electrolyte leakage rate, superoxide anion (O2·-) production rate and the accumulation of malondialdehyde (MDA) content. After storage, the firmness of G. biloba seeds coated with chitosan alone and chitosan/nanocomposite were markedly higher than those of control. Higher activities of scavenger antioxidant enzymes including peroxidase (POD), superoxide dismutase (SOD), and catalase (CAT) were enhanced in the chitosan/nano-TiO2 and chitosan/nano-SiO2 coating treatments during storage time. Either the composite treatment of chitosan with nano-TiO2 or chitosan/nano-SiO2 exhibited desirable performance in inhibiting mildew occurrence, shrinkage and maintaining the firmness of G. biloba seeds, positively affect the antioxidant activity in G. biloba seeds, thereby leading to the enhancement of seed quality. Coating G. biloba seeds with chitosan/nano-TiO2 or chitosan/nano-SiO2 is a potential method for commercial preservation.


Assuntos
Quitosana/química , Ginkgo biloba/química , Nanopartículas/química , Sementes/química , Dióxido de Silício/química , Titânio/química , Catalase/metabolismo , Eletrólitos/metabolismo , Etilenos/química , Malondialdeído/metabolismo , Nanopartículas/ultraestrutura , Peroxidase/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Superóxido Dismutase/metabolismo , Superóxidos/metabolismo , Difração de Raios X
6.
Food Chem ; 270: 385-394, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30174062

RESUMO

The color change of the jujube fruit after harvest is used as a quality indicator. The effects of abscisic acid (ABA) and a chitosan/nano-silica/sodium alginate composite film on the color development and qualitative properties of harvested jujube in cold storage were investigated. The results indicate that a composite film could prolong the shelf life of post-harvested winter jujube for approximately 1 month, while the ABA treatment induced ripening and reduced the quality. A significant positive correlation between the a∗/b∗ values, water loss and the malondialdehyde (MDA) content was found for fruits in cold storage. In comparison with the control and ABA-treated fruit, superoxide dismutase (SOD), polyphenol oxidase (PPO) and peroxidase (POD) activities were lower than those in a composite film-treated fruit. In addition, the dihydroflavonol-4-reductase (DFR) is the primary gene that regulates the expression of anthocyanin.


Assuntos
Ácido Abscísico/farmacologia , Quitosana/farmacologia , Cor , Ziziphus/química , Ácido Algínico , Frutas/efeitos dos fármacos , Dióxido de Silício
7.
J Sci Food Agric ; 99(6): 3124-3133, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30536731

RESUMO

BACKGROUND: The effects of Ginkgo biloba seed exopleura extract (GSEE) and chitosan (CH) coating on the preservation of ginkgo seeds were investigated. RESULTS: Results showed that CH could alleviate the decay rate, and that CH combined with GSEE (CH-GSEE) treatment further inhibited the development of seed decay due to the additional antifungal activity of GSEE. The nutrient contents, including water, starch and soluble protein, were maintained by both CH-GSEE and CH treatments. CH-GSEE treatment led to better restriction on oxidative stress by decreasing superoxide anion production rate, membrane permeability, malondialdehyde content, respiration rate and ethylene production rate. The antioxidant enzyme activities of peroxidase, superoxide dismutase and catalase in ginkgo seeds were maintained by treatment with CH-GSEE at a higher level. These results were consistent with the enhanced visual appearance, qualities and storability of the CH-GSEE-treated seeds. Principal component analysis provided a global view of the internal relations of the ginkgo seeds with different treatments. CONCLUSIONS: The postharvest qualities of CH-GSEE-treated seeds were better than those of other treatment groups. Therefore, CH-GSEE is an effective and alternative way for inhibiting decay, maintaining quality and extending the postharvest life of ginkgo seeds. © 2018 Society of Chemical Industry.


Assuntos
Quitosana/química , Ginkgo biloba/química , Sementes/química , Ginkgo biloba/metabolismo , Malondialdeído/metabolismo , Peroxidase/metabolismo , Proteínas de Plantas/metabolismo , Controle de Qualidade , Sementes/metabolismo , Superóxido Dismutase/metabolismo , Superóxidos/metabolismo
8.
J Agric Food Chem ; 2018 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-30507107

RESUMO

Our previous work has demonstrated that α-linolenic acid (ALA)-loaded oil-in-water (O/W) microemulsion could enhance ALA antioxidant capacity. Meanwhile, we also observed that synthesized microemulsion itself had fluorescence. In this work, we have prepared a multiple water-in-oil-in-water (W/O/W) microemulsion to further enhance ALA antioxidant capacity and activate this delivery carrier application potential with a free label. The compositions of primary water-in-oil (W/O) microemulsion were obtained using pseudo-ternary phase diagrams, and then W/O/W microemulsion was prepared adopting the "two-step heterotherm method". The conductivity of W/O/W microemulsion was measured to lie between 250.0 and 350.0 µs/cm. The spherical droplets with a mean particle diameter of 10.0-20.0 nm were confirmed by transmission electron microscopy and dynamic light scattering. Nuclear magnetic resonance confirmed that ALA diffused to the multiple water-oily interface simultaneously. In addition, the in vitro release and antioxidant capacity measurements of ALA-loaded W/O/W microemulsion concluded the sustained-release effect and excellent antioxidant capacity. The fluorescent intensity of W/O/W microemulsion was markedly increased in comparison to O/W microemulsion. The synthesized microemulsion could lead to important applications and have advantages of a label-free fluorescent carrier for optical imaging purposes.

9.
Methods Mol Biol ; 1744: 89-102, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29392658

RESUMO

Senescence is the terminal stage of plant development. It is a strategic and tactical response to seasonal and unpredictable stresses. As an important part of plant senescence, fruit ripening is normally viewed distinctly as climacteric or non-climacteric. In this chapter we describe protocols for the determination of a number of parameters that have been used in characterizing the ripening behavior of fruits. These include changes in respiratory rate, ethylene, flesh firmness, sugar, acidity, starch, pectin, enzymes, aroma volatiles, and expression of ripening-related genes during fruit ripening and senescence.

10.
Biosens Bioelectron ; 106: 122-128, 2018 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-29414078

RESUMO

Food safety always remains a grand global challenge to human health, especially in developing countries. To solve food safety pertained problems, numerous strategies have been developed to detect biological and chemical contaminants in food. Among these approaches, nanomaterials-based biosensors provide opportunity to realize rapid, sensitive, efficient and portable detection, overcoming the restrictions and limitations of traditional methods such as complicated sample pretreatment, long detection time, and relying on expensive instruments and well-trained personnel. In this review article, we provide a cross-disciplinary perspective to review the progress of nanomaterials-based biosensors for the detection of food contaminants. The review article is organized by the category of food contaminants including pathogens/toxins, heavy metals, pesticides, veterinary drugs and illegal additives. In each category of food contaminant, the biosensing strategies are summarized including optical, colorimetric, fluorescent, electrochemical, and immune- biosensors; the relevant analytes, nanomaterials and biosensors are analyzed comprehensively. Future perspectives and challenges are also discussed briefly. We envision that our review could bridge the gap between the fields of food science and nanotechnology, providing implications for the scientists or engineers in both areas to collaborate and promote the development of nanomaterials-based biosensors for food safety detection.


Assuntos
Técnicas Biossensoriais , Contaminação de Alimentos , Metais Pesados/isolamento & purificação , Praguicidas/isolamento & purificação , Toxinas Biológicas/isolamento & purificação , Técnicas Eletroquímicas , Inocuidade dos Alimentos , Humanos , Metais Pesados/toxicidade , Nanoestruturas/química , Praguicidas/toxicidade , Toxinas Biológicas/toxicidade
11.
Food Res Int ; 104: 126-133, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29433777

RESUMO

The effects of CPe-III on hyperlipidemic mice were investigated, along with molecular docking and dynamics analyses between CPe-III and CETP. This study was conducted in order to explore the lipid metabolism potential and mechanism of CPe-III. CPe-III significantly (P<0.05) reduced serum total cholesterol, triglyceride and hepatic triglyceride levels and increased serum superoxide dismutase activity. CPe-III reversed liver changes induced by a high-fat diet and significantly (P<0.05) reduced kidney and epididymal fat indices. The activities of hepatic lipase and lipoprotein lipase, as well as fecal fat excretion, were significantly (P<0.05) enhanced. Furthermore, CPe-III was found to bind in the cavity of CETP, forming four stable hydrogen bonds. Hydrophobic interactions were the main driving force during binding. This study demonstrates that CPe-III improves dyslipidemia in mice. The binding of CPe-III to CETP demonstrates that CPe-III blocks cholesterol transport. These results indicate that CPe-III may be useful as an adjuvant element for hyperlipidemia and atherosclerosis therapies.

12.
Adv Healthc Mater ; 7(5)2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29280301

RESUMO

DNA has arisen as a promising building material for the construction of hydrogels owing to its unique properties such as designability and biocompatibility. All-DNA hydrogels with only DNA molecules may have limited applications; hence a composite DNA hydrogel with multifunctional moieties is highly desired to cater for specific applications. Herein, a multifunctional DNA hydrogel is created by incorporating DNA with silver nanoclusters (AgNCs), in which AgNCs render the hydrogel simultaneously with fluorescent and antibacterial functions. A circular DNA is rationally designed, which allows for the elongation of DNA chain via an enzymatic polymerization as well as the formation of AgNCs onto DNA scaffolds. The resultant hybrid DNA hydrogel not only shows distinctive morphology and mechanical properties, but also exhibits fluorescent and antibacterial functions. These characteristics, along with its biocompatibility, will allow the hydrogel to be suitable for a variety of potential biomedical applications such as tissue engineering, wound dressing, biosensing, and bioimaging.

13.
Int J Med Mushrooms ; 19(9): 839-848, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29199558

RESUMO

Breast cancer affects millions of women annually worldwide and is the leading cause of cancer death in women. Various bioactive phytochemicals based on natural products are considered to be an important source of chemopreventive agents. In this study we report-to our knowledge for the first time-9 phytochemicals isolated by nuclear magnetic resonance spectroscopy and mass spectrometry from the acetic ether extract of Pleurotus nebrodensis and identified as (1) ergosterol, (2) uracil, (3) ergosterol-3-O-ß-D-glucopyranoside, (4) cerevisterol, (5) cerebroside B, (6) 5'-methylthioadenosine, (7) adenosine, (8) hypoxanthine, and (9) uridine. Their bioactivities were screened with an MTT assay using breast cancer MCF-7 cells in vitro. As a result, about half of the isolated compounds demonstrated moderate or strong inhibitory activity in a concentration-dependent manner. Among them, compound 1 (ergosterol) exhibited superior activity and the lowest half-maximal inhibitory concentration (112.65 µmol/L). Further mechanistic study elucidated that compound 1 led to significant S-phase cell cycle arrest and induced apoptosis in MCF-7 cells. Our study shows the mycochemical composition of the P. nebrodensis mushroom and provides guidance for use of compound 1 as a promising lead in cancer therapy.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Ergosterol/farmacologia , Pleurotus/química , Quimioprevenção , Feminino , Humanos , Células MCF-7
14.
Front Plant Sci ; 8: 1231, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28769946

RESUMO

Salt stress affects the plant quality, which affects the productivity of plants and the quality of water storage. In a recent study, we conducted the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) analysis and RNA-Seq, bioinformatics study methods, and detection of the key genes with qRT-PCR. Our findings suggested that the optimum salt treatment conditions are 200 mM and 19d for the identification of salt tolerance in tomato. Based on the RNA-Seq, we found 17 amino acid metabolic and 17 carbohydrate metabolic pathways enriched in the biological metabolism during the response to salt stress in tomato. We found 7 amino acid metabolic and 6 carbohydrate metabolic pathways that were significantly enriched in the adaption to salt stress. Moreover, we screened 17 and 19 key genes in 7 amino acid metabolic and 6 carbohydrate metabolic pathways respectively. We chose some of the key genes for verifying by qRT-PCR. The results showed that the expression of these genes was the same as that of RNA-seq. We found that these significant pathways and vital genes occupy an important roles in a whole process of adaptation to salt stress. These results provide valuable information, improve the ability to resist pressure, and improve the quality of the plant.

15.
J Agric Food Chem ; 65(19): 3842-3850, 2017 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-28447802

RESUMO

Extensive studies have demonstrated that biochanin A (BCA) has a significant hypolipidemic effect. However, its mechanism of action is not clear. In this context, the effect of BCA on a high-fat diet (HFD)-induced hyperlipidemia in mice was determined. The results showed that treatment with a medium dose of biochanin A (BM) significantly decreased low-density lipoprotein cholesterol (LDL-C) 85% (from 1.196 ± 0.183 to 0.181 ± 0.0778 mM) and total cholesterol (TC) 39% (from 5.983 ± 0.128 to 3.649 ± 0.374 mM) levels, increased lipoprotein lipase (LPL) 96% (from 1.421 ± 0.0982 to 2.784 ± 0.177 U/mg protein) and hepatic triglyceride lipase (HTGL) 78% (from 1.614 ± 0.0848 to 2.870 ± 0.0977 U/mg protein) activities, significantly improved fecal lipid levels, and lowered the epididymal fat index in hyperlipidemic mice compared with the HFD control mice (p < 0.05). In vitro, the high antioxidant capacity of BCA was determined by the FRAP assay, ABTS•+ scavenging method, and an ROS assay. In RAW 264.7 macrophages, a dose of 10 µM BCA significantly increased the cholesterol efflux by 18.7% compared with the control cells. Moreover, molecular docking of BCA on cholesterol ester transfer protein (CETP) (Asn24 and Thr27 at the N-terminal; Ala274 and Phe270 at the C-terminal) gave new insights into the role of BCA in preventing cholesterol ester transport.


Assuntos
Genisteína/administração & dosagem , Hiperlipidemias/tratamento farmacológico , Hipolipemiantes/administração & dosagem , Metabolismo dos Lipídeos/efeitos dos fármacos , Animais , Colesterol/metabolismo , Proteínas de Transferência de Ésteres de Colesterol/metabolismo , Genisteína/química , Humanos , Hiperlipidemias/metabolismo , Hipolipemiantes/química , Lipase Lipoproteica/metabolismo , Fígado/efeitos dos fármacos , Fígado/enzimologia , Fígado/metabolismo , Masculino , Camundongos , Simulação de Acoplamento Molecular , Triglicerídeos/metabolismo
16.
Food Funct ; 8(4): 1414-1437, 2017 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-28287659

RESUMO

The aryl hydrocarbon receptor (AhR) is a pleiotropic nuclear factor that was originally recognized as a "master" of xenobiotic metabolism but demonstrated recently to be a vital regulator of many normal physiological events. Understanding of the mechanism of action of AhR-targeted compounds, as represented by polyphenols (the greatest source of xenobiotic AhR modulators in the human diet) is of critical importance for the development of polyphenol-based nutraceutical strategies or the prevention of AHR-mediated toxicity associated with polyphenol intake. In this review, based on studies conducted over the past decade, we summarized the modes of function of polyphenolic AhR modulators. Furthermore, we made a brief mechanistic synopsis of the pharmacological/therapeutic use of polyphenols as AhR antagonists, selective AhR regulators and dual AhR/ER modulators, and underscored their potential in the prevention/treatment of common human diseases/disorders. Additionally, interesting subjects for further mechanistic investigations on polyphenolic AhR modulators have been provided.


Assuntos
Polifenóis/farmacologia , Receptores de Hidrocarboneto Arílico/antagonistas & inibidores , Animais , Tratamento Farmacológico , Humanos , Receptores de Hidrocarboneto Arílico/metabolismo , Transdução de Sinais , Xenobióticos/farmacologia
17.
J Agric Food Chem ; 64(38): 7095-103, 2016 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-27584867

RESUMO

It was previously found that CPe-III-S, synthesized according to the chickpea peptide CPe-III (RQSHFANAQP), exhibited an antiproliferative effect. The aim of this study was to investigate the antiproliferative mechanism of CPe-III-S. CPe-III-S was treated by pepsin and trypsin in a simulated gastrointestinal digestion environment as well as in an animal experiment. With HPLC-ESI-MS analysis, three peptide fragments of Ser-His, His-Phe, and Ala-Asn-Ala-Gln were identified. Ser-His was the only common product from both in vitro and in vivo environments. The specific bindings between three peptides and p53-R273H were performed by molecular docking, and the molecular dynamic simulation between Ser-His and p53-R273H revealed the stability of the binding complex. The binding free energy of the complex was -12.56 ± 1.03 kcal/mol with a reliable hydrogen bond between the ligand and Thr284 of p53. Ser-His may restore mutant p53-R273H activity or inhibit its binding with a downstream signal. This metabolite is a potential anticancer factor for suppressing cell proliferation.


Assuntos
Dipeptídeos/farmacologia , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Proteína Supressora de Tumor p53/metabolismo , Animais , Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Feminino , Humanos , Células MCF-7 , Camundongos , Camundongos Endogâmicos BALB C , Pepsina A/química , Fragmentos de Peptídeos/farmacologia , Conformação Proteica , Tripsina/química , Proteína Supressora de Tumor p53/genética
18.
J Food Sci ; 81(7): H1816-24, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27257791

RESUMO

Hypobaric treatment is becoming a potential technology to protect fruits from postharvest decay. The objective of this study was to investigate the effects of hypobaric treatments on storage quality, bioactive compounds, and antioxidant activity of tomato fruit. In this study, green tomatoes (cv. "Fen guan") were treated with hypobaric pressures (0.04 and 0.07 MPa) at ambient temperature (20 ℃) for 28 d. The results showed that under hypobaric storage, the respiration rates significantly declined and the respiratory peaks postponed 12 and 8 d by 0.04 and 0.07 MPa treatments, respectively, compared to control. Total soluble solid, titratable acidity, ascorbic acid, and lycopene were retained by hypobaric treatment. Moreover, ascorbic acid contents treated with 0.04 and 0.07 MPa were, respectively, 37% and 26% higher than control at day 24 and the contents of total polyphenols were, respectively, 1.28 and 1.11 times higher than control. Production and accumulation of toxic substances were significantly restrained. The ethanol content decreased, respectively, by 53% and 84% than control. At later storage period, the superoxide dismutase activity in treated fruits was about 0.58 U/(g·FW·min), whereas only 0.29 U/(g·FW·min) in control. Hypobaric treatment not only maintained a high activity of superoxide dismutase and peroxidase (POD), but also improved antioxidant capacity. All the results indicated that hypobaric treatment was a potential helpful method to protect the quality and nutrition of tomato and prolong ripening of tomato. Furthermore, the effect of 0.04 MPa hypobaric treatment was found better than 0.07 MPa.


Assuntos
Antioxidantes/análise , Manipulação de Alimentos/métodos , Frutas/química , Lycopersicon esculentum/química , Pressão , Antioxidantes/farmacologia , Ácido Ascórbico/análise , Carotenoides/análise , Respiração Celular , Armazenamento de Alimentos , Frutas/normas , Humanos , Licopeno , Extratos Vegetais/análise , Polifenóis/análise , Superóxido Dismutase/análise , Superóxido Dismutase/farmacologia
19.
Mol Genet Genomics ; 291(3): 1205-17, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26852223

RESUMO

NAC proteins comprise a large family of transcription factors that play important roles in diverse physiological processes during development. To explore the role of NAC transcription factors in the ripening of fruits, we predicted the secondary and tertiary structure as well as regulative function of the SNAC4 (SlNAC48, Accession number: NM 001279348.2) and SNAC9 (SlNAC19, Accession number: XM 004236996.2) transcription factors in tomato. We found that the tertiary structure of SNAC9 was similar to that of ATNAP, which played an important role in the fruit senescence and was required for ethylene stimulation. Likewise, the bio-function prediction results indicated that SNAC4 and SNAC9 participated in various plant hormone signaling and senescence processes. More information about SNACs was obtained by the application of VIGS (virus-induced gene silencing). The silencing of SNAC4 and SNAC9 dramatically repressed the LeACS2, LeACS4 and LeACO1 expression, which consequently led to the inhibition of the ripening process. The silencing of SNACs down-regulated the mRNA levels of the ethylene perception genes and, at the same time, suppressed the expression of ethylene signaling-related genes except for LeERF2 which was induced by the silencing of SNAC4. The expressions of LeRIN were different in two silenced fruits. In addition, the silencing of SNAC4 reduced its mRNA level, while the silencing of SNAC9 induced its expression. Furthermore, the silencing of LeACS4, LeACO1 and LeERF2 reduced the expression of SNAC4 and SNAC9, while the silencing of NR induced the expression of all of them. In particular, these results indicate that SNAC transcription factors bind to the promoter of the ethylene synthesis genes in vitro. This experimental evidence demonstrates that SNAC4 and SNAC9 could positively regulate the tomato fruit ripening process by functioning upstream of ethylene synthesis genes. These outcomes will be helpful to provide a theoretical foundation for further exploring the tomato fruit ripening and senescence mechanism.


Assuntos
Etilenos/síntese química , Lycopersicon esculentum/crescimento & desenvolvimento , Reguladores de Crescimento de Planta/genética , Fatores de Transcrição/química , Fatores de Transcrição/genética , Etilenos/biossíntese , Frutas/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Inativação Gênica , Lycopersicon esculentum/química , Lycopersicon esculentum/genética , Lycopersicon esculentum/metabolismo , Modelos Moleculares , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regiões Promotoras Genéticas , Estrutura Terciária de Proteína , Transdução de Sinais , Fatores de Transcrição/metabolismo
20.
Food Sci Technol Int ; 2015 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-26437672

RESUMO

Consumer demand for safe and nutritious fruits and vegetables has given rise to the development of a number of nonthermal food preservation techniques. Recent studies have highlighted that antioxidant activity of fruits and vegetables plays an important role in human health. In this paper, the influences of nonthermal preservation technologies, including pulsed electric field, radiation processing, dense phase carbon dioxide, ozone processing, and edible coatings, on the antioxidant capacity and related compounds in fruits and vegetables are reviewed. The proposed mechanisms and future trends are also discussed to accelerate the further commercialization and exploration of these novel technologies, which will, in turn, help to promote human health.

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