Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 13 de 13
Filtrar
1.
J Biotechnol ; 356: 42-50, 2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-35914618

RESUMO

This study evaluated the effects of the exogenous application of ethylenediaminetetraacetic acid (EDTA), indole-3-acetic acid (IAA) and iron sulfate (FeSO4) upon the phytochemical mechanisms of fenugreek grown under Pb-excess (2000 mg L-1 PbCl2). The results showed that chemical additives of EDTA and IAA as well as FeSO4 improved fenugreek germination parameters. The radicle length and the amylase activity were significantly improved under IAA treatment compared to EDTA and FeSO4. Exogenous FeSO4 was more effective to improving growth parameters. Moreover, the decrease in hydrogen peroxide (H2O2) and malondialdehyde (MDA) levels was noted under all chemical additives especially under IAA application. In addition, it was more effective than EDTA and Fe in increasing catalase, glutathione (GSH), ascorbate peroxidase (APX), flavonoids and phenols while the increment superoxide dismutase (SOD) production was more pronounced under EDTA addition to Pb than other chelators. HPLC analysis revealed that the gallic was the major phenol produced under all chelators addition especially with IAA. In addition, the syringic acid was only produced with exogenous IAA while the quercetin was only detected under EDTA addition. Our results exhibited a higher IAA efficiency than EDTA and FeSO4 in mitigating Pb stress in fenugreek through up-regulated mechanisms of the antioxidant system for reducing reactive oxygen species (ROS) activities and enhancing special phenols.


Assuntos
Trigonella , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Catalase/metabolismo , Quelantes/metabolismo , Ácido Edético/metabolismo , Ácido Edético/farmacologia , Glutationa/metabolismo , Peróxido de Hidrogênio/farmacologia , Ácidos Indolacéticos , Chumbo/metabolismo , Chumbo/toxicidade , Estresse Oxidativo , Fenóis/metabolismo , Compostos Fitoquímicos/metabolismo , Superóxido Dismutase/metabolismo , Trigonella/metabolismo
2.
Foods ; 10(3)2021 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-33801354

RESUMO

Two globe artichoke genotypes, "Spinoso sardo" and "Opera F1", have been processed as ready-to-cook (RTC) slices and refrigerated at 4 °C for 12 days (i) to evaluate the suitability to be processed as RTC slices; (ii) to evaluate the effect of a Foeniculum vulgare essential oil (EO) emitter, within an active package system, to delay quality decay, thus extending shelf life; (iii) to estimate the impact of EO emitter on the sensory profile of the RTC slices after cooking. Results revealed that both globe artichoke genotypes possess a good attitude to be processed as RTC product. "Opera F1" showed the best performances for color parameters, texture and chemical indexes, while "Spinoso sardo" showed lower mass loss (ML) over the storage time. The addition of EO emitter slowed down the consumption of O2, better preserved texture when compared to the control and more effectively control polyphenol oxidase (PPO) activity and antioxidants' retention during the cold storage. Microbial counts in control globe artichoke RTC slices were significantly higher than those packed with EO emitter, confirming the inhibiting role played by EO of F. vulgare. In addition, the EO emitter did not influence negatively the sensory profile of RTC globe artichoke slices after microwave cooking.

3.
Foods ; 10(2)2021 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-33671803

RESUMO

The aim of the study was to assess, through a comparative shelf-life test, the suitability of two packaging materials, namely macro-perforated polypropylene (PP MA) and micro-perforated coextruded polypropylene (PP C), for the quality preservation of green asparagus (Asparagus officinalis L. 'Vegalim'). Quality of spears was evaluated during 30 days at refrigerated storage by monitoring chemical, physical, and enzymatic parameters as well as sensory descriptors. PP C kept headspace composition close to suggested values for fresh green asparagus. Total color difference increased during the storage and it was highly correlated with chlorophyll-a and carotenoids, however, sensory color perception did not change significantly until 22 days of storage. PP C maintained ascorbic acid concentrations close to the initial levels, limited total phenolic compound loss to 24% (45% in PP MA), determined an increase of 72% in fiber content and small changes in lignin value; enzymatic changes were significantly inhibited. Significant sensorial differences were detected after 22 days of storage, with PP C performing better than PP MA. PP C film was confirmed as the best choice, limiting weight loss and maintaining a fresh-like appearance during 30 days of storage, thus allowing an extension in postharvest life.

4.
Materials (Basel) ; 13(15)2020 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-32759717

RESUMO

For food packaging, plastic materials display large appeal, mostly due to their versatility, mechanical, optical and barrier properties. However, they play an important role in environmental concerns and waste management issue. Compostable bioplastics represent alternative materials designed for a lower environmental impact. In this work, a biobased compostable packaging, constituted by polylactide (PLA) trays and NatureFlex™ film, was evaluated for fresh-cut cherry tomato. A comparative analysis was accomplished using traditional packaging materials, that is, polyethylene terephtalate (PET) trays and polypropylene (PP Coex) film. Structural stability under food contact conditions, mechanical and physical-chemical properties were investigated. Tensile mechanical properties, puncture resistance, contact angle (CA) and attenuated total reflection Fourier-transform infrared spectroscopy (ATR-FTIR), before and after UV or radiofrequency (RF) sterilization treatment, were evaluated. UV irradiation method resulted the less invasive one. Therefore, oxygen and water vapor transmission rate (OTR and WVTR), overall chemical migration test, biodegradation assessment by biochemical oxygen demand (BOD) according to ISO 14851 and disintegration test by ISO 20200 were carried out to establish the further influence of UV sterilization on the packaging. Overall, data showed that the biobased compostable packaging for a prolonged shelf-life of fresh-cut cherry tomato has better properties that were surprisingly enhanced by the UV treatment.

5.
J Sci Food Agric ; 100(9): 3719-3728, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32248537

RESUMO

BACKGROUND: Potato yields and tuber compositions are linked to mechanisms adopted by plants to cope with salinity and often can change after cooking. The current study aimed to evaluate the effects of salinity, variety and cooking method in the composition of potato tubers. Three potato varieties (Spunta, Bellini and Alaska) grown under distinct salt levels (T1: 2.2 ms cm-1 EC, T2: 8.5 ms cm-1 EC before electromagnetic treatment and 6.3 ms cm-1 EC after electromagnetic treatment, T3: 8.5 ms cm-1 EC) were studied. Yield and tuber quality attributes (starch, dry matter, specific density and tuber size) were evaluated. Carotenoids, total and individual phenolics determined by high-performance liquid chromatography (HPLC), relative antioxidant capacity (RAC) and ions content were analyzed, in both raw and water boiled tubers. RESULTS: Tuber yield, starch, dry matter, ions and antioxidants were significantly influenced by the salinity level and variety. The least production and the highest antioxidants were obtained under T3. Antioxidants were influenced by cooking method, the interactions treatment × cooking method and variety × cooking method. Individual phenolic compounds exhibited different response to cooking as quercetin, caffeic acid and catechin decreased significantly after boiling. However, coumaric acid increased in Alaska tubers. CONCLUSION: Salinity level, variety and cooking method are important determinants of tuber yield and composition. Electromagnetic water may be useful to enhance potato production and tuber quality in areas suffering from water salinization. © 2020 Society of Chemical Industry.


Assuntos
Antioxidantes/química , Fenóis/química , Tubérculos/crescimento & desenvolvimento , Cloreto de Sódio/análise , Solanum tuberosum/química , Antioxidantes/metabolismo , Culinária , Fenóis/metabolismo , Tubérculos/química , Tubérculos/metabolismo , Salinidade , Cloreto de Sódio/metabolismo , Solo/química , Solanum tuberosum/crescimento & desenvolvimento , Solanum tuberosum/metabolismo , Amido/química , Amido/metabolismo
6.
J Sci Food Agric ; 99(11): 5219-5228, 2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31049967

RESUMO

BACKGROUND: The globe artichoke [Cynara cardunculus var. scolymus (L.) Fiori] is a natural source of minerals, fiber, inulin, and polyphenols. A ready-to-cook (RTC) version of this product could improve its commercialization and consumption. In this study, the effects of (i) anti-browning treatments (citric acid 0.5% + ascorbic acid 2%, or cysteine 0.5%, w/v) and (ii) dipping in locust bean gum (LBG) edible coating with or without Foeniculum vulgare essential oil (EO) were evaluated on RTC globe artichoke slices cv. 'Spinoso sardo' during storage (11 days at 4 °C). Fresh weight loss, color, texture, polyphenol oxidase (PPO), microbiological and chemical parameters, antioxidant capacity, and sensory descriptors were determined. RESULTS: The results showed that, despite the antioxidant treatment used, when EO was added to LBG, all microbiological groups underwent an average reduction of 0.50 log CFU g-1 . Cysteine preserved the antioxidant capacity, color, and texture of samples better than citric acid and ascorbic acid, and inhibited PPO; the addition of EO to LBG enhanced these effects. At the end of the storage period, the overall highest sensory attribute score was attained by the coated globe artichoke samples with EO. CONCLUSION: The marked efficacy of the LBG edible coating with added F. vulgare EO in maintaining microbiological, physical, chemical, and sensory qualities makes it a promising processing tool for the preservation of ready-to-cook Spinoso sardo globe artichoke slices during storage for 11 days at 4 °C. © 2019 Society of Chemical Industry.


Assuntos
Cynara scolymus/química , Fast Foods/análise , Foeniculum/química , Aditivos Alimentares/análise , Conservação de Alimentos/métodos , Óleos Voláteis/análise , Óleos de Plantas/análise , Cor , Culinária , Conservação de Alimentos/instrumentação , Humanos , Polifenóis/análise , Paladar
7.
Food Chem ; 244: 275-283, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29120782

RESUMO

"Long storage" tomato is a crop traditionally cultivated in the Mediterranean area under no water supply, that recently has attracted the interest of breeders for its high tolerance to drought and as potential genetic source in breeding programs for water stress resistance. A collection of 28 genotypes of "long storage" tomato (Solanum lycopersicum L.) was studied for carotenoid and polyphenol profile and content, vitamin C, and other physico-chemical traits of fruits. Tomato carotenoids and polyphenols were identified and quantified using high-performance liquid chromatography coupled with diode array detection and electrospray-mass spectrometry (HPLC/DAD/ESI-MS); nineteen different phenolic compounds and six different carotenoids, for a total of 25 markers, have been detected, quantified and used to discriminate among the different landraces to find out which could be the best candidate for a medium-to-large scale cultivation. Different statistical approaches (ANOVA, Principal Components Analysis, Cluster Analysis) have been used for data analysis.


Assuntos
Fenômenos Químicos , Armazenamento de Alimentos , Variação Genética , Solanum lycopersicum/química , Solanum lycopersicum/metabolismo , Ácido Ascórbico/análise , Carotenoides/análise , Frutas/química , Cromatografia Gasosa-Espectrometria de Massas , Solanum lycopersicum/genética , Polifenóis/análise
8.
J Sci Food Agric ; 96(6): 2040-6, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26089187

RESUMO

BACKGROUND: This study was performed to test the effects of pre-treating cherry tomatoes with a solution containing citric acid-NaCl-CaCl2 (10:10:24 g L(-1)), followed by one of three different drying regimes (40, 60, 80 °C) on the antioxidant capacity of their aqueous extracts and the extent of phenolic compound degradation. RESULTS: Chlorogenic acids, caffeic acid, ferulic acid, rutin and naringenin were all detected in the aqueous extracts. In fresh cherry tomatoes the predominant phenolic compound was rutin, followed by naringenin, which corresponded to 79% and 8% of the total phenolic compounds present, respectively. Pre-treatment was protective towards naringenin and had a modest protective effect on rutin and ferulic acid (0.1 > P > 0.05). Total phenolic content was similar in all samples, but there was a trend for the level of free polyphenols to be lower in treated tomatoes. The destruction of naringenin was confirmed by liquid chromatographic-mass spectrometric data. CONCLUSION: A significant effect of temperature on the antioxidant capacity was observed. After this treatment the industry might introduce some advances in the processing of tomatoes, preserving the main nutritive characteristics and saving the products as semi-dried.


Assuntos
Antioxidantes/química , Frutas/química , Hidroxibenzoatos/química , Polifenóis/química , Solanum lycopersicum/química
9.
Cell Cycle ; 13(4): 652-65, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24345738

RESUMO

Malignant mesothelioma, a very aggressive tumor associated to asbestos exposure, is expected to increase in incidence, and unfortunately, no curative modality exists. Reactivation of p53 is a new attractive antitumoral strategy. p53 is rarely mutated in mesothelioma, but it is inactivated in most tumors by the lack of p14(ARF). Here, we evaluated the feasibility of this approach in pleural mesothelioma by testing RITA and nutlin-3, two molecules able to restore p53 function through a different mechanism, on a panel of mesothelioma cell lines representing the epithelioid (NCI-H28, NCI-H2452, IST-MES 2), biphasic (MSTO-211H), and sarcomatoid (NCI-H2052) histotypes compared with the normal mesothelial HMC-hTERT. RITA triggered robust caspase-dependent apoptosis specifically in epithelioid and biphasic mesothelioma cell lines, both through wild-type and mutant p53, concomitant to p21 downregulation. Conversely, nutlin-3 induced a p21-dependent growth arrest, rather than apoptosis, and was slightly toxic on HMC-hTERT.   Interestingly, we identified a previously undetected point mutation of p53 (p.Arg249Ser) in IST-MES 2, and showed that RITA is also able to reactivate this p53 mutant protein and its apoptotic function. RITA reduced tumor growth in a MSTO-211H-derived xenograft model of mesothelioma and synergized with cisplatin, which is the mainstay of treatment for this tumor. Our data indicate that reactivation of p53 and concomitant p21 downregulation effectively induce cell death in mesothelioma, a tumor characterized by a high intrinsic resistance to apoptosis. Altogether, our findings provide the preclinical framework supporting the use of p53-reactivating agents alone, or in combination regimens, to improve the outcome of patients with mesothelioma.


Assuntos
Apoptose/efeitos dos fármacos , Furanos/farmacologia , Imidazóis/farmacologia , Neoplasias Pulmonares/metabolismo , Mesotelioma/metabolismo , Piperazinas/farmacologia , Neoplasias Pleurais/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cisplatino/administração & dosagem , Cisplatino/farmacologia , Sinergismo Farmacológico , Xenoenxertos , Humanos , Neoplasias Pulmonares/patologia , Mesotelioma/patologia , Mesotelioma Maligno , Mutação , Neoplasias Pleurais/patologia , Proteínas rho de Ligação ao GTP/metabolismo
10.
J Cell Physiol ; 228(3): 525-35, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22886479

RESUMO

The retinoblastoma (RB) family of proteins, including RB1/p105, retinoblastoma-like 1 (RBL1/p107), and retinoblastoma-like 2 (RBL2/p130), is principally known for its central role on cell cycle regulation. The inactivation of RB proteins confers a growth advantage and underlies multiple types of tumors. Recently, it has been shown that RB proteins have other important roles, such as preservation of chromosomal stability, induction and maintenance of senescence and regulation of apoptosis, cellular differentiation, and angiogenesis. RB proteins are involved in many cellular pathways and act as transcriptional regulators able to bind several transcription factors, thus antagonizing or potentiating their functions. Furthermore, RB proteins might control the expression of specific target genes by recruiting chromatin remodeling enzymes. Although many efforts have been made to dissect the different functions of RB proteins, it remains still unclear which are necessary for cancer suppression and the role they play at distinct steps of carcinogenesis. Moreover, RB proteins can behave differently in various cell types or cell states. Elucidating the intricate RB protein network in regulating cell fate might provide the knowledge necessary to explain their potent tumor suppressor activity and to design novel therapeutic strategies.


Assuntos
Neoplasias/patologia , Neoplasias/fisiopatologia , Proteína do Retinoblastoma/fisiologia , Animais , Apoptose/fisiologia , Diferenciação Celular/fisiologia , Senescência Celular/fisiologia , Progressão da Doença , Genes do Retinoblastoma , Instabilidade Genômica , Humanos , Modelos Biológicos , Neoplasias/irrigação sanguínea , Neoplasias/genética , Neovascularização Patológica , Proteína Supressora de Tumor p53/fisiologia
11.
Cell Cycle ; 11(9): 1841-50, 2012 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-22544282

RESUMO

Distinct molecular pathways could be constitutively active in mouse T-Antigen positive and T-Antigen negative medulloblastoma cell lines, contributing to their phenotypic differences as well as to cellular responses, cell cycle progression, cell death and survival. The diversity of these responses may be due, at least in part, to distinct activities of Rb2/p130, CTCF and BORIS proteins in response to an altered network of signaling evoked by the T-Ag presence. Here, we provided evidence supporting a role for the T-Antigen in causing chronic endoplasmic reticulum (ER) stress and aberrant Caspase-12 expression and activation, subsequently driving to both massive cell death, and perhaps selection of cells with a higher malignant phenotype. Furthermore, we observed that the endoplasmic stress, either chronically caused by T-Ag or transiently induced by glucose deprivation, is accompanied by the formation of complexes between the retinoblastoma related protein Rb2/p130 and the chromatin insulator CCCTC-binding factor CTCF, or the CTCF-paralogue BORIS. Our study represents the first evidence supporting a role of the T-Antigen in inducing/maintaining chronic ER-stress, as well as, indicating a role of Rb2/p130, CTCF and BORIS as potential mediators of non-canonical ER-dependent death pathway in mouse medulloblastoma.


Assuntos
Antígenos Virais de Tumores/metabolismo , Morte Celular , Estresse do Retículo Endoplasmático , Retículo Endoplasmático/patologia , Meduloblastoma/patologia , Animais , Apoptose , Fator de Ligação a CCCTC , Caspase 12/metabolismo , Imunoprecipitação da Cromatina , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Retículo Endoplasmático/metabolismo , Ativação Enzimática , Regulação Neoplásica da Expressão Gênica , Glucose/metabolismo , Meduloblastoma/genética , Meduloblastoma/metabolismo , Camundongos , Camundongos Transgênicos , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Proteína p130 Retinoblastoma-Like/genética , Proteína p130 Retinoblastoma-Like/metabolismo , Transdução de Sinais , Células Tumorais Cultivadas , Microambiente Tumoral
12.
J Food Sci ; 76(4): S225-32, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-22417367

RESUMO

Nitrogen fertilization is useful for obtaining higher growth and quality of productions, and the use of nitrogen fertilization is widespread. To evaluate the influence of nitrogen-rich fertilizers on quality characteristics of celery, shelf life tests of celery grown with 2 levels of nitrogen and 2 different nitrogen fertilizers were performed. The treatments of the celery samples were identified as follows: T1, mineral nitrogen (80 kg ha(-1)); T2, mineral nitrogen (120 kg ha(-1)); T3, organic nitrogen (80 kg ha(-1)); T4, organic nitrogen (120 kg ha(-1)); R4, residual organic nitrogen (120 kg ha(-1)); and C, untreated control. Celery plants were selected and packaged in either of the following 2 plastic films: antifog polyolefin (AFP) film or microperforated polypropylene (MPP) film. The nitrate contents, weight loss, hardness, changes in color parameters, and total phenols were studied for both packaging types during storage. The results demonstrated that celery fertilized with organic nitrogen and packaged in AFP film reached a shelf life of 37 d. The control sample packaged in MPP film was not marketable after 20 d, but the same untreated sample packaged in AFP film reached a shelf life of 30 d.


Assuntos
Apium/química , Fertilizantes , Embalagem de Alimentos/métodos , Conservação de Alimentos/métodos , Nitrogênio/metabolismo , Cor , Nitratos/análise
13.
J Cell Physiol ; 223(1): 143-50, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20039270

RESUMO

RB loss has long been recognized as the causative genetic alteration underlying retinoblastoma but it is increasingly evident that other alterations are required for the tumor to develop. Therefore, we set out to identify additional inheritable susceptibility markers and new potential preventive and therapeutic targets for retinoblastoma. We focused on the p16INK4A tumor suppressor gene because of its possible role in retinoblastoma pathogenesis and its involvement in predisposition to familial cancer. p16INK4A expression was analyzed in tumor samples from retinoblastoma patients by immunohistochemistry and in peripheral blood cells from both patients and their parents by real-time quantitative reverse transcription-PCR (qRT-PCR). Since promoter methylation is a common mechanism regulating p16INK4A expression, the methylation status of its promoter was also analyzed in blood samples from patients and their parents by methylation-specific PCR. A downregulation of p16INK4A was observed in 55% of retinoblastoma patients. Interestingly, in 56% of the cases showing p16INK4A downregulation at least one of the patients' parents bore the same alteration in blood cells. Analysis of p16INK4A promoter methylation showed hypermethylation in most patients with p16INK4A downregulation and in the parents with the same alteration in p16INK4A expression. The finding that p16INK4A was downregulated both in patients and their parents suggests that this alteration could be a novel inheritable susceptibility marker to retinoblastoma. The observation that p16INK4A downregulation seems to be due to its promoter hypermethylation opens the way for the development of new preventive and therapeutic strategies using demethylating agents.


Assuntos
Biomarcadores Tumorais/genética , Inibidor p16 de Quinase Dependente de Ciclina/genética , Metilação de DNA , Regulação Neoplásica da Expressão Gênica , Regiões Promotoras Genéticas , Neoplasias da Retina/genética , Retinoblastoma/genética , Biomarcadores Tumorais/análise , Criança , Pré-Escolar , Inibidor p16 de Quinase Dependente de Ciclina/análise , Regulação para Baixo , Feminino , Predisposição Genética para Doença , Humanos , Imuno-Histoquímica , Lactente , Masculino , Linhagem , Fosforilação , RNA/análise , Neoplasias da Retina/química , Neoplasias da Retina/patologia , Retinoblastoma/química , Retinoblastoma/patologia , Proteína do Retinoblastoma/análise , Proteína p130 Retinoblastoma-Like/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Risco
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA