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1.
Food Funct ; 12(22): 11250-11261, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34708849

RESUMO

Microbial fermentation with lactic acid bacteria (LAB) is a natural food biopreservation method. Yellow mustard and milk whey are optimum substrates for LAB fermentation. The aim of the present study was to evaluate the bioaccessibility and bioavailability of bioactive compounds from yellow mustard flour and milk whey both with and without LAB fermentation. All extracts were subjected to a simulated digestion process. Total polyphenols, DL-3-phenyllactic acid (PLA), lactic acid, and the antioxidant activity were determined in the studied matrices before and after simulated digestion. Yellow mustard flour was significantly richer in total polyphenols, whereas significantly higher concentrations of PLA and lactic acid were observed in milk whey. Similar antioxidant activity was determined in both ingredients being in all cases strongly reduced after in vitro digestion. Higher bioaccessibility was found for polyphenols and PLA in milk whey. Transepithelial transport of total polyphenols was higher in yellow mustard flour compared to milk whey, reaching bioavailability values between 3-7% and 1-2%, respectively. PLA transepithelial transport was only significant in both fermented matrices with bioavailability around 4-6%. Transepithelial transport of lactic acid reached values of 31-34% (bioavailability ∼ 22%) and 15-78% (bioavailability ∼ 3%) in milk whey and yellow mustard flour, respectively. LAB fermentation showed beneficial effects on enriching extracts with PLA, lactic acid, and antioxidant activity, as well as increasing bioaccessibility of these acids in yellow mustard flour and total polyphenol bioavailability in milk whey. Results pointed to yellow mustard flour and milk whey as natural preservative ingredients used in the food industry, especially when fermented with LAB.


Assuntos
Antioxidantes , Lactobacillales/metabolismo , Leite/metabolismo , Mostardeira/química , Soro do Leite/metabolismo , Animais , Antioxidantes/química , Antioxidantes/farmacocinética , Disponibilidade Biológica , Células CACO-2 , Fermentação/fisiologia , Humanos , Lactatos/química , Lactatos/farmacocinética , Ácido Láctico/química , Ácido Láctico/farmacocinética
2.
Food Chem Toxicol ; 121: 437-443, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30227181

RESUMO

Enniatin B is a ionophoric and lipophilic mycotoxin which reaches the bloodstream and has the ability to penetrate into cellular membranes. The purpose of this study was to reveal changes in the gene expression profile caused by enniatin B in human Jurkat lymphoblastic T-cells after 24 h of exposure at 1.5, 3 and 5 µM by next generation sequencing. It was found that up to 27% of human genome expression levels were significantly altered (5750 genes for both down-regulation and up-regulation). In the three enniatin B concentrations studied 245 differentially expressed genes were found to be overlapped, 83 were down and 162 up-regulated. ConsensusPathDB analysis of over-representation of differentially expressed genes provided a list of gene ontology terms in which several biological processes related to nucleoside monophosphate metabolic process, respiratory chain complex, electron transport chain, oxidative phosphorylation and cellular respiration were the most altered. Also, an interesting correlation was found between enniatin B toxicity and the up-regulation of the UCP protein complex. In summary, the transcriptomic analysis revealed that mitochondria are the organelles showing more related differentially expressed genes. Consequently, differentially expressed genes involved in biological processes, molecular functions and pathways related to mitochondrial metabolism and respiration were significantly changed.


Assuntos
Depsipeptídeos/farmacologia , Complexo de Proteínas da Cadeia de Transporte de Elétrons/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Linfócitos T/metabolismo , Regulação para Baixo/efeitos dos fármacos , Complexo de Proteínas da Cadeia de Transporte de Elétrons/genética , Humanos , Células Jurkat , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Linfócitos T/efeitos dos fármacos , Transcriptoma/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos
3.
Food Chem Toxicol ; 115: 127-135, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29530640

RESUMO

Several mycotoxins exert their effect on the immunological system; some are classified as immunotoxic. Jurkat T-cells were used to study toxic effects of beauvericin (BEA) and enniatin B (ENN B). Both are not legislated mycotoxins with increasing presence in feed and food. Concentrations studied were from 1 to 15 µM at 24, 48 and 72 h. Cell death by increasing the percentage of apoptotic/necrotic cells was: BEA > ENN B. IC50 values ranged from 3 to 7.5 µM for BEA. ENN B 15 µM decreased viability (21-29%). The percentage of apoptotic/necrotic cells was BEA > ENN B at 24 h but not at 48 h. Caspase-3&7 activation profile varied, although both mycotoxins increased this activation. No difference in ROS production for any mycotoxin was observed. Arrest in S phase for both mycotoxins was obtained. BEA increased the percentage of DNA in the tail (18% and 20%) with respect to the control, whereas not for ENN B. In summary, cytotoxicity of BEA involved mitochondrial alterations; while ENN B only at highest concentrations and time assayed. BEA had cell cycle disturbances and apoptotic and apoptotic/necrotic cells increased; for ENN B these were not evident. Different toxic responses in Jurkat T-cells may be involved in BEA and ENN B toxicity.


Assuntos
Depsipeptídeos/toxicidade , Micotoxinas/toxicidade , Linfócitos T/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Caspase 3/genética , Caspase 3/metabolismo , Caspase 7/genética , Caspase 7/metabolismo , Ciclo Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Depsipeptídeos/análise , Humanos , Micotoxinas/análise , Linfócitos T/citologia , Linfócitos T/enzimologia
4.
Toxicol Lett ; 284: 213-221, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29203277

RESUMO

Beauvericin (BEA), an ionophoric cyclic hexadepsipeptide mycotoxin, is able to increase oxidative stress by altering membrane ion permeability and uncoupling oxidative phosphorylation. A toxicogenomic study was performed to investigate gene expression changes triggered by BEA exposure (1.5, 3 and 5 µM; 24 h) in Jurkat cells through RNA-sequencing and differential gene expression analysis. Perturbed gene expression was observed in a concentration dependent manner, with 43 differentially expressed genes (DEGs) overlapped in the three studied concentrations. Gene ontology (GO) analysis showed several biological processes related to electron transport chain, oxidative phosphorylation, and cellular respiration significantly altered. Molecular functions linked to mitochondrial respiratory chain and oxidoreductase activity were over-represented (q-value < 0.01). Pathway analysis revealed oxidative phosphorylation and electron transport chain as the most significantly altered pathways in all studied doses (z-score > 1.96; adj p-value < 0.05). 77 genes involved in the respiratory chain were significantly down-regulated at least at one dose. Moreover, 21 genes related to apoptosis and programmed cell death, and 12 genes related to caspase activity were significantly altered, mainly affecting initiator caspases 8, 9 and 10. The results demonstrated BEA-induced mitochondrial damage affecting the respiratory chain, and pointing to apoptosis through the caspase cascade in human lymphoblastic T cells.


Assuntos
Apoptose/efeitos dos fármacos , Depsipeptídeos/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Transcriptoma/efeitos dos fármacos , Apoptose/genética , Técnicas de Cultura de Células , Permeabilidade da Membrana Celular/efeitos dos fármacos , Permeabilidade da Membrana Celular/genética , Relação Dose-Resposta a Droga , Transporte de Elétrons , Perfilação da Expressão Gênica , Ontologia Genética , Humanos , Células Jurkat , Fosforilação Oxidativa , Estresse Oxidativo/genética
5.
Rev. toxicol ; 34(2): 84-93, jul.-dic. 2017. tab
Artigo em Inglês | IBECS | ID: ibc-169817

RESUMO

The worldwide implementation and certification of food safety management systems (FSMS) have significantly increased during the last decade, reflecting the importance of assuming these standards in activity sectors involved in the food chain. Companies of all types and sizes worldwide have made several efforts for implementing a FSMS based on International Organization for Standardization (ISO) 22000. Certification system and quality management tools development in international context, are analyzed in food processing and food service sectors. Studies of food safety, performance of ISO 22000 implemented in food companies and hurdles of context characteristics wherein operate were reviewed. To summarize, improved product quality and safety has been identified as the major benefit of implementing ISO 22000. Other benefits highlighted include enhanced employee skills, improved company image, increased product sales, increased market share and access to new markets (AU)


La implementación y certificación mundial de los sistemas de gestión de la seguridad alimentaria (SGSA) se han incrementado significativamente durante la última década, lo que refleja la importancia de asumir estos estándares en los sectores de actividad involucrados en la cadena alimentaria. Empresas de todos los tipos y tamaños han realizado esfuerzos para implementar un SGSA basado en la Organización Internacional de Normalización (ISO) 22000. El sistema de certificación y el desarrollo de herramientas de gestión de calidad en el contexto internacional se analizan en los sectores de procesamiento de alimentos y servicios de alimentos. Se revisaron los estudios de inocuidad de los alimentos, el desarrollo de ISO 22000 implementado en las empresas de alimentos y los problemas según las características del contexto en donde opera. En resumen, la mejora en la calidad y seguridad del producto ha sido identificada como el principal beneficio de implementar ISO 22000. Otros beneficios destacados incluyen mejoras en las habilidades de los empleados, en la imagen de la compañía, mayores ventas de productos, mayor participación de mercado y acceso a nuevos mercados (AU)


Assuntos
Humanos , Gestão da Segurança/organização & administração , 50328 , Indústria de Processamento de Alimentos/normas , Certificado de Boas Práticas de Fabricação , Certificado de Registro de Produtos , Serviços de Alimentação/normas , Doenças Transmitidas por Alimentos/prevenção & controle
6.
Food Chem Toxicol ; 78: 185-206, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25680507

RESUMO

This review summarizes the information regarding the in vivo studies of Fusarium mycotoxins in the last decade. The most common studies are classified as subacute toxicity, subchronic toxicity, acute toxicity, toxicokinetic studies and teratogenicity in order of importance. The most used animals in in vivo studies are pigs, rats, chickens and mice. Fumonisin B1, deoxynivalenol, zearalenone, nivalenol and T-2 toxin are the most studied fusarotoxins. Studies with combinations of mycotoxins are also frequent, deoxynivalenol generally being one of them. The predominant route of administration is oral, administered mostly in the form of naturally contaminated feed. Other administration routes also used are intraperitoneal, intravenous and subcutaneous. In vivo research on Fusarium mycotoxins has increased since 2010 highlighting the need for such studies in the field of food and feed safety.


Assuntos
Fusarium/química , Micotoxinas/análise , Micotoxinas/toxicidade , Ração Animal/microbiologia , Animais , Galinhas , Qualidade de Produtos para o Consumidor , Modelos Animais de Doenças , Contaminação de Alimentos/análise , Microbiologia de Alimentos , Fumonisinas/análise , Fumonisinas/toxicidade , Camundongos , Ratos , Suínos , Toxina T-2/análise , Toxina T-2/toxicidade , Tricotecenos/análise , Tricotecenos/toxicidade , Zearalenona/análise , Zearalenona/toxicidade
7.
Ophthalmic Physiol Opt ; 21(4): 327-33, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11430627

RESUMO

The stenopaeic slit is a trial case accessory used in subjective refraction, especially when high astigmatism is present. In spite of its simplicity, the effect of the slit when it is not oriented along one of the principal meridians of the examined eye is difficult to predict, even in terms of classical geometrical optics. In this paper, the optical principles of the slit are considered with full details in the theoretical framework of the dioptric power space. An analytical expression to obtain the residual refractive error when a stenopaeic slit is placed in front of an astigmatic eye at any orientation is deduced. In the light of these results, some aspects of the clinical procedure are discussed.


Assuntos
Astigmatismo/fisiopatologia , Modelos Biológicos , Refração Ocular/fisiologia , Testes Visuais/instrumentação , Acomodação Ocular/fisiologia , Humanos , Óptica e Fotônica , Testes Visuais/métodos
8.
Ophthalmic Epidemiol ; 8(1): 27-37, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11262680

RESUMO

Ophthalmic epidemiological studies frequently deal with ocular refractive errors, which are commonly expressed in the form sphere/cylinder x axis. However, this representation has been shown not to be the most suitable one for performing statistical analysis. Although alternative analytical and graphic methods to represent this kind of data have been developed, these formalisms have often gone unnoticed by researchers, despite their usefulness and versatility. Besides, there has been no discussion of how each of them fits in with a particular type of study. In this paper, several mathematical representations of dioptric power are revisited in a comprehensive way. The aim is to encourage researchers in ophthalmology and optometry to use these formalisms in their epidemiological studies, thus profiting from their exactitude and simplicity. Consequently, the emphasis is not on complicated mathematical derivations but on how to use these representations. Their potential and suitability in different applications is analyzed in detail. In addition, some examples are presented to illustrate the mathematical methods considered.


Assuntos
Astigmatismo/epidemiologia , Modelos Estatísticos , Óptica e Fotônica , Refração Ocular , Astigmatismo/fisiopatologia , Interpretação Estatística de Dados , Humanos , Matemática
9.
Optom Vis Sci ; 78(2): 106-12, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11265925

RESUMO

A novel heuristic approach to the well-known representation of the dioptric power in a three-dimensional space is presented. It is shown how this theoretical framework is ideal for discussing the principles of several subjective refraction methods. In particular, this formalism is used to justify the stenopaic slit refraction, the Barnes subjective refraction technique, and the Jackson cross-cylinder procedure. In view of this analysis, some modifications to the traditional procedures are proposed.


Assuntos
Modelos Teóricos , Óptica e Fotônica , Refratometria
10.
Opt Lett ; 26(19): 1501-3, 2001 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-18049648

RESUMO

A single analytical formulation for evaluating the focal shift in any apodized nontelecentric focusing setup is reported. The formulation is also useful in the case of imaged paraxial beams. We show explicitly that the magnitude of the focal shift is determined by only one parameter that depends on the effective width of the pupil filter and its axial position. To illustrate our approach we examine different focusing setups.

11.
Opt Lett ; 26(23): 1861-3, 2001 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-18059718

RESUMO

We present a new method with which to binarize pupil filters designed to control the three-dimensional irradiance distribution in the focal volume of an optical system. The method is based on a one-dimensional iterative algorithm, which results in efficient use of computation time and in simple, easy to fabricate binary filters. An acceptable degree of resemblance between the point-spread function of the annular binary filter and that of its gray-tone counterpart is obtained.

12.
Appl Opt ; 40(19): 3164-8, 2001 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-11958254

RESUMO

The scalar field in the focal volume of nontelecentric apodized focusing systems cannot be accurately described by the Debye integral representation. By use of the Fresnel-Kirchhoff diffraction formula it is found that, if the aperture stop is axially displaced, the focal-volume structure is tuned. We analyze the influence of the apodizing function and find that, whereas axially superresolving pupil filters are highly sensitive to the focal-volume reshaping effect, axially apodizing filters are more inclined to the focal-shift effect.

13.
J Opt Soc Am A Opt Image Sci Vis ; 17(7): 1185-91, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10883970

RESUMO

The Debye formulation of focused fields has been systematically used to evaluate, for example, the point-spread function of an optical imaging system. According to this approximation, the focal wave field exhibits some symmetries about the geometrical focus. However, certain discrepancies arise when the Fresnel number, as viewed from focus, is close to unity. In that case, we should use the Kirchhoff formulation to evaluate accurately the three-dimensional amplitude distribution of the field in the focal region. We make some important remarks regarding both diffraction theories. In the end we demonstrate that, in the paraxial regime, given a defocused transverse pattern in the Debye approximation, it is possible to find a similar pattern but magnified and situated at another plane within the Kirchhoff theory. Moreover, we may evaluate this correspondence as the action of a virtual thin lens located at the focal plane and whose focus is situated at the axial point of the aperture plane. As a result, we give a geometrical interpretation of the focal-shift effect and present a brief comment on the problem of the best-focus location.

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