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1.
Braz. J. Pharm. Sci. (Online) ; 55: e18005, 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1039053

RESUMO

Moringa leaves and spinach used as vegetables containing cyanogens and polyphenols having suspected antithyroidal activity; however, detailed studies in this aspect found unavailable. Goitrogenic/antithyroid potentiality of those plant foods of Indian origin was evaluated. To explore the goitrogenic/antithyroid effect of those plant foods cyanogenic glucosides, glucosinolates, thiocyanate and polyphenol content were measured. These plant foods were fed with diet regularly to adult male albino rats for 30 and 60 days respectively, followed by evaluation of morphological and functional status of thyroid,as thyroid gland weight, the activity status of thyroid hormone synthesizing enzymes viz. TPO, Na+-K+-ATPase, deiodinase I, thyroid hormone profiles, thyroid histoarchitecture as well as urinary iodine and thiocyanate. In moringa leaves and spinach fed diet, there was a significant increase in urinary excretion of thiocyanate and iodine, enlargement of thyroid gland along with hypertrophy of thyroid follicles and altered in the activities of thyroid hormone synthesizing enzymes with concomitant changes of thyroid hormone profiles. Effects were more severe in moringa leaves treated group than that of spinach. Biochemical analysis moringa leaves and spinach reveal that those are rich sources of goitrogens and their prolonged consumption gradually developed a relative state of biochemical and morphological hypothyroidism.


Assuntos
Animais , Masculino , Ratos , Antitireóideos/análise , Moringa oleifera/efeitos adversos , Spinacia oleracea/efeitos adversos , Hipotireoidismo , Índia/etnologia
2.
An. acad. bras. ciênc ; 89(4): 2975-2986, Oct.-Dec. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-886851

RESUMO

ABSTRACT The intercropping is a production system that aims to provide increased yield with less environmental impact, due to greater efficiency in the use of natural resources and inputs involved in the production process. An experiment was carried out to evaluate the agronomic viability of kale and New Zealand spinach intercropping as a function of the spinach transplanting time. (0, 14, 28, 42, 56, 70, 84 and 98 days after transplanting of the kale). The total yield (TY) and yield per harvest (YH) of the kale in intercropping did not differ from those obtained in monoculture. The spinach TY was influenced by the transplanting time, the earlier the transplanting, the higher the TY. The spinach YH was not influenced by the transplanting time, but rather by the cultivation system. In intercropping, the spinach YH was 13.5% lower than in monoculture. The intercropping was agronomically feasible, since the land use efficiency index, which was not influenced by the transplanting time, had an average value of 1.71, indicating that the intercropping produced 71% more kale and spinach than the same area in monoculture. Competitiveness coefficient, aggressiveness and yield loss values showed that kale is the dominating species and spinach is the dominated.


Assuntos
Brassica/crescimento & desenvolvimento , Spinacia oleracea/crescimento & desenvolvimento , Produção Agrícola/métodos , Fatores de Tempo , Nova Zelândia
3.
Arch. latinoam. nutr ; 64(1): 59-68, mar. 2014. ilus, tab
Artigo em Inglês | LILACS | ID: lil-752692

RESUMO

The present study aimed to determine the effects of different traditional cooking methods on folate (tetrahydrofolate - THF, 5-methyltetrahydrofolate - 5- MTHF and 5-formyltetrahydrofolate - 5-FTHF) retention in leafy vegetables. The analysis of folates was carried out by high performance liquid chromatography (HPLC), with detection by fluorescence, using gradient elution, mobile phase of acetonitrile and phosphate buffer solution. The retention of isomers in vegetables after cooking ranged from 17.0 % to 87.2 % for THF, 53.4 - 94.1% for 5-MTHF and 39.0 - 107.9% for 5-FTHF. The retention of folates depended on the food matrix, the kind of isomer, and the cooking methods used. It is recommended that one should have more control over the choices for methods and time of cooking and the amount of water used at home and at foodservice as well.


El presente estudio tuvo como objetivo determinar los efectos de los diferentes métodos de cocción tradicionales sobre la retención de folatos (tetrahidrofolato - THF, 5-metiltetrahidrofolato - 5- MTHF y 5-formiltetrahidrofolato - 5 FTHF) en hortalizas. El análisis de folatos se llevó a cabo por cromatografía líquida de alta resolución (CLAR), con detección por fluorescencia, usando elución en gradiente, fase móvil de acetonitrilo y solución tampón de fosfato. La retención de los isómeros en las hortalizas después de la cocción varió de 17,0% a 87,2% para THF, 53,4 a 94,1% para 5-MTHF y de 39,0 a 107,9% para 5- FTHF. La retención de folatos dependió de la matriz del alimento, el tipo de isómero, y los métodos de cocción utilizados. Se recomienda que uno debe tener más control sobre las opciones de métodos y tiempo de cocción y la cantidad de agua utilizada en el hogar y también en los servicio de alimentación.


Assuntos
Brassica/química , Culinária/métodos , Leucovorina/análise , Spinacia oleracea/química , Tetra-Hidrofolatos/análise , Brasil , Brassica/classificação , Cromatografia Líquida de Alta Pressão , Fatores de Tempo
4.
Braz. j. microbiol ; 44(3): 693-699, July-Sept. 2013. ilus, tab
Artigo em Inglês | LILACS | ID: lil-699801

RESUMO

Campylobacteriosis is a worldwide distributed zoonosis. One of the main virulence factors related to Campylobacter spp. in animals and humans is the cytolethal distending toxin (CDT), encoded by three adjacent genes (cdtA, cdtB, cdtC). The occurrence of Campylobacter spp. in samples of vegetables has not been reported in Brazil yet, and has seldom been described in the international literature. The detection of CDT in these strains has not been reported, either. The objectives of the present study were to determine the occurrence of Campylobacter spp. strains carrying virulence factors in samples of poultry and vegetables (lettuce and spinach) from different points of sale, thus verifying if vegetables are as an important vehicle for potentially virulent Campylobacter spp. strains as poultry. Twenty four strains were identified as Campylobacter jejuni by phenotypic and genotypic methods: 22 from broiler carcasses and two from lettuce samples. Three strains were identified as Campylobacter coli: two from broiler carcasses and one from lettuce. The presence of the cdt genes were detected in 20/24 (83.3%) C. jejuni strains, and 3/3 (100%) C. coli strains. The isolation of Campylobacter spp. strains with the cdt gene cluster in lettuce samples points to a new possible source of contamination, which could have an impact in the vegetable production chain and risk to public health. Results show that potentially virulent C. jejuni and C. coli strains remain viable in samples of broiler carcasses and vegetables at the points of sale.


Assuntos
Animais , Toxinas Bacterianas/genética , Campylobacter coli/isolamento & purificação , Campylobacter jejuni/isolamento & purificação , Galinhas/microbiologia , Alface/microbiologia , Spinacia oleracea/microbiologia , Fatores de Virulência/genética , Brasil , Campylobacter coli/classificação , Campylobacter coli/genética , Campylobacter jejuni/classificação , Campylobacter jejuni/genética , Prevalência
5.
São Paulo; s.n; s.n; jul. 2013. 95 p. tab, graf, ilus.
Tese em Português | LILACS | ID: biblio-837014

RESUMO

Nos últimos anos, vegetais têm sido responsáveis por surtos de enfermidades transmitidas por alimentos (ETA) em diversas regiões do mundo por serem veículos dos mais diferentes micro-organismos patogênicos, entre eles Salmonella spp, Listeria monocytogenes e Escherichia coli produtora de toxina de Shiga (STEC). O uso de sanitizantes nem sempre reduz de maneira significativa a população de micro-organismos presentes nos vegetais, sendo necessária a aplicação de técnicas mais eficientes, entre elas, a radiação gama. Assim, os objetivos do presente estudo foram avaliar o efeito da irradiação na redução de STEC, Salmonella spp. e L. monocytogenes inoculadas em espinafre minimamente processado, bem como sobre os atributos físico-químicos e sensoriais do vegetal. Amostras de espinafre (Tetragonia expansa) foram inoculadas com um "pool" de cepas de Salmonella spp, um "pool" de cepas de L. monocytogenes e um "pool" de cepas de STEC, separadamente, e expostas às doses de 0; 0,2; 0,4; 0,6; 0,8 e 1,0 kGy. Os valores de D10 para Salmonella spp, L. monocytogenes e STEC foram, respectivamente, 0,19 a 0,20 kGy, 0,20 a 0,21 kGy e 0,17 kGy. Foram avaliados os comportamentos de Salmonella spp, L. monocytogenes e STEC em amostras de espinafre expostas à doses cinco vezes maiores do que o valor D10 obtido para cada micro-organismo: 1,0; 1,05 e 0,85 kGy, respectivamente, e em amostras não irradiadas armazenadas por 12 dias a (4±1) °C e a (10±1) °C. Os resultados mostram que as doses empregadas reduziram a população de Salmonella e de STEC em aproximadamente 6 ciclos log no dia zero tendo permanecido abaixo do limite de detecção (<10 UFC/g), mesmo após 12 dias de armazenamento em ambas as temperaturas. A dose de 1,05 kGy reduziu a população de L. monocytogenes em, aproximadamente, 5 log imediatamente após a irradiação, porém com recuperação de 2,62 log nas amostras armazenadas a (10±1) °C ao final do período de armazenamento. Amostras de espinafre expostas às doses de 1 e 1,5 kGy e a amostra-controle, mantidas sob refrigeração (4±1) ºC, foram utilizadas para a avaliação da vida de prateleira (VP), análise sensorial, análise de cor, determinação de ácido ascórbico, flavonoides, compostos fenólicos e capacidade antioxidante. A VP da amostra exposta à dose de 1 kGy foi de 15 dias, dois dias a mais que a da amostra-controle, enquanto a exposta a 1,5 kGy apresentou VP de 12 dias. Todas as amostras expostas à radiação foram aceitas pelos provadores. A irradiação não provocou alterações significativas na concentração de compostos fenólicos e atividade antioxidante, porém houve alteração na cor e na concentração de flavonoides. As estações do ano, por sua vez, tiveram influência sobre a coloração, concentração de compostos fenólicos e atividade antioxidante. Apesar da alteração na coloração ter sido observada na análise instrumental, esta não foi percebida pelos provadores durante a análise sensorial. O processo de irradiação mostrou ser uma boa alternativa para aumentar a segurança microbiológica de espinafre sem alterar as características sensoriais. No entanto, o uso das Boas Práticas de Fabricação nunca deve ser negligenciado


In recent years, fresh produce have been responsible for foodborne disease outbreaks worldwide, due to their contamination by different pathogenic microorganisms such as Salmonella spp., Listeria monocytogenes and Shiga toxin-producing Escherichia coli (STEC). The use of sanitizers does not always significantly reduce the microbial populations present in vegetables, and thus, the application of more efficient techniques such as gamma radiation, is required. The objectives of this study were to evaluate the effect of irradiation on the reduction of the populations of STEC, Salmonella spp. and L. monocytogenes, inoculated on minimally processed spinach, as well as to assess its effect on the sensory and physicochemical characteristics of the vegetable. Spinach (Tetragonia expansa) samples were individually inoculated, with a cocktail of three strains of Salmonella spp, three strains of L. monocytogenes and three strains of STEC and exposed to doses of 0, 0.2; 0.4; 0.6; 0.8 and 1.0 kGy. The D10 values determined in this study ranged from 0.19 to 0.20 kGy for Salmonella spp, 0.20 to 0.21 kGy for L. monocytogenes, and 0.17 kGy for STEC. The behavior of Salmonella spp., L. monocytogenes and STEC were evaluated in spinach samples exposed to doses of 1.0, 1.05 and 0.85 kGy, respectively, and in non-irradiated samples, stored for 12 days at (4±1) °C and (10±1) °C. The results showed that the populations of Salmonella and STEC were reduced at about 6 log, on day zero, and remained below the detection limit (<10 CFU/g) even after 12 days of storage at both temperatures tested. The 1.05 kGy dose reduced the population of L. monocytogenes in approximately 5 log, but in the samples stored at (10±1) °C, the growth of the microorganism (2,62 log) was observed at the end of the storage time. Spinach samples exposed to 1 and 1.5 kGy, as well as the control sample, all kept under refrigeration (4±1) °C were used for the evaluation of the product shelf life, sensory analysis, color analysis, determination of ascorbic acid, flavonoids, phenolic compounds and the antioxidant capacity. The samples exposed to 1 kGy displayed a shelf life of 15 days, two days longer than that observed for the control sample, while those exposed to 1.5 kGy showed a shelf life of 12 days. All samples exposed to radiation were accepted by the sensorial panel. The irradiation had no significant effect either on the concentration of phenolic compounds or on the antioxidant activity. Nevertheless, there was a reduction in the concentration of flavonoids and change on the color. The color, phenolic compounds concentration and antioxidant activity were influenced by the seasons of the year. Although the change in color was observed by instrumental analysis, this was not perceived by the panelists during sensory analysis. The irradiation process is a great alternative for microbiological safety purpose together with Good Manufacturing Practices


Assuntos
Irradiação de Alimentos/métodos , Spinacia oleracea/efeitos da radiação , Armazenamento de Substâncias, Produtos e Materiais , Colimetria , Escherichia coli/classificação , Listeria monocytogenes/crescimento & desenvolvimento , Salmonella/química , Toxina Shiga
6.
Rev. chil. nutr ; 37(2): 201-207, jun. 2010. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-577386

RESUMO

Vitamin C stability, new variables of cultivation, management and post harvest conservation of vegetables and culinary treatments before consumption can produce modifications in the content of this vitamin. To obtain actualized information of vitamin C content in fresh and processed food, this nutrient was determined in spinach in the fresh state and after subjected to current methods of conservation. Vitamin C determination by HPLC included ascorbic and dehydroascorbic acid. Mean values of vitamin C (mean +SD) in spinach were: fresh, 44.0 +/- 8,74 mg/100g; quick frozen, 24,2+14.81 mg/100g; and canned, 25.0 +/-1.9 mg/100g. This variability depends of genotypic factors and conservation conditions. Microwave and steam cooking generated the most retention of the nutrient, while boiling generated great losses of both vitamin forms.


La labilidad de la vitamina C, las nuevas variables de cultivo, manejo y conservación postcosecha de los vegetales y los tratamientos culinarios previos a su consumo pueden provocar modificaciones en el contenido de este nutriente. Para contar con información actualizada y propia del contenido de vitamina C en alimentos frescos y procesados, se determinó este nutriente en espinacas frescas y sometidas a los métodos de conservación actuales considerando también, la influencia de los sitios de expendio y la aplicación de los tratamientos culinarios más comunes. La determinación de vitamina C, constituida por ácido ascórbico y dehidroascórbico, se realizó empleando HPLC. Los valores medios de vitamina en espinacas sin procesar y su desvío estándar son 44.0 y 8,74 mg/100g, en productos supercongelados 24,2 y 14,81 mg/100g y en conservas de 25.0 y 1.9 mg/100g. Esta variabilidad depende de factores genotípicos y condiciones de conservación. La cocción por microondas y vapor generaron las mayores retenciones del nutriente, mientras que el hervor provocó grandes pérdidas de ambas formas vitamínicas.


Assuntos
Ácido Ascórbico/análise , Alimentos Congelados/análise , Temperatura Alta , Spinacia oleracea/química , Cromatografia Líquida de Alta Pressão , Conservação de Alimentos
7.
Artigo em Português | LILACS | ID: lil-537817

RESUMO

The objective of this work was to assess the effects of the kale stalk flour (KSF) and the spinach stalk flour (SSF) on the intestinal tract and on the biochemical parameters of the rats. The stalk flours (ST) were preparedwith dehydrated kale stalks (KSF) and spinach stalks (SSF). The chemical composition of these SF was determined as described by Association of Official Analytical Chemists International (1995). Fifteen rats were dividedinto 3 groups. During 12 days, they were fed AIN-93M diets: control diet (group 1), 30% KSF diet (group 2) and 30% SSF diet (group 3). The weight, intake and fecal material were checked every 48 hours. The density of the feces was analyzed according to the method described by Ferreira (2002); and the feces were morphologically analyzed by SEM and fibers were quantified by the method of Van Soest. The cecal weight and pH were determined by the method of Adolfo Lutz Institute (2005). Blood glucose was measured in an ACCU-CHEK® apparatus, and lipids were determined by an enzymatic method. It was observed that the ST has a high content of insoluble dietary fiber. The dietary intake and weight gain were similar for all groups. Feeding ST resulted in a higher (p <0.05) fecal excretionand density, greater percentage of fibers in feces and presence of plant residue. There was no difference in the fecal weight and pH of the groups. Fasting plasma glucose was significantly lower in the SSF group. As for lipids, the groups fed the ST showed lower levels of triacylglycerols (p<0.05).It was concluded that FT are good sources of insoluble dietary fiber, showing significant effect in the intestinal tract with increased fecal excretion and discrete biochemical changes.


El objetivo del estudio fue evaluar los efectos delas harinas de tallo de repollo (FTC) y espinaca (FTE) en el tracto intestinal y parámetros bioquímicos de ratas. Las harinas de tallos fueron confeccionadas con tallos de repollo manteca y espinaca deshidratados. La composición química fue determinada de acuerdo con la Association of Official Analytical Chemists International (1995). Quince ratas fueron distribuidas en 3 grupos. Durante 12 días recibieron dietas AIN-93M: dieta control (grupo1), dieta con 30% de FTC (grupo 2) y con 30%de FTE (grupo 3). El peso, ingesta y materia fecal fueron controlados cada 48 horas. La densidadde las heces siguió método de Ferreira (2002); estas se analizaron morfológicamente en microscopio electrónico de exploración y secuantificaron las fibras por Van Soest. El peso y pH fecal fueron determinados - Instituto Adolfo Lutz (2005). La glucemia fue realizada con el instrumento ACCU-CHEK® y los lípidos por medio del método enzimático. Los resultados mostraron que las FT pose en alto contenido de fibra alimentar insoluble. La ingesta de la dietay la ganancia ponderal fueron similares entrelos grupos. La oferta de las FT resulto en mayor(p<0.05) excreción y densidad fecal, mayor porcentaje de fibras en las heces y presencia de residuo vegetal. El peso y pH fecal no diferíanentre los grupos. La glucemia en ayuno fue significativamente menor en el grupo FTE. Encuanto a los lípidos, los grupos sometidos a FT presentaron menores niveles de triglicéridos(p<0.05). Se concluye, que las FT son buenas fuentes de fibra alimentar insoluble, presentandoun efecto importante en el tracto intestinal conun aumento de excreción fecal y discretas modificaciones bioquímicas.


O objetivo do trabalho foi avaliar os efeitos das farinhas de talo de couve (FTC) e espinafre (FTE) no trato intestinal e parâmetros bioquímicos deratos. As farinhas de talos (FT) foram confeccionadas com talos de couve-manteiga e espinafre desidratados. A composição química foi determinada segundo Association of Official Analytical Chemists International (1995).Quinze ratos foram distribuídos em 3 grupos. Durante 12 dias receberam dietas AIN-93M:dieta controle (grupo 1), dieta com 30% de FTC (grupo 2) e com 30% de FTE (grupo 3). O peso, ingesta e material fecal foram tomados a cada 48h. A densidade das fezes seguiu método de Ferreira (2002); analisaram-se morfologicamente estas ao MEV e quantificaram-se fibras por VanSoest. O peso e pH cecal foram determinados -Instituto Adolfo Lutz (2005). A glicemia foi realizada em aparelho ACCU-CHEK®, e os lipídios através de método enzimático. Observou-se que as FT possuem alto teor de fibra alimentar insolúvel. A ingestão dietética e ganho ponderal foram similares entre os grupos. A oferta das FT resultou em maior (p<0,05)excreção e densidade fecal, maior porcentagem de fibras nas fezes e presença de resíduo vegetal. O peso e pH cecal não diferiram entre os grupos. A glicemia de jejum foi significativamente menor no grupo FTE. Quanto aos lipídios, os grupos submetidos às FT apresentaram menores níveis de triacilgliceróis (p<0,05). Concluiu-se que as FT são boas fontes de fibra alimentar insolúvel, apresentando expressivo efeito no trato intestinal com aumento da excreção fecal e discretas modificações bioquímicas.


Assuntos
Animais , Masculino , Ratos , Alimentos Formulados , Caules de Planta , Brassica/química , Fibras na Dieta , Spinacia oleracea/química
8.
Braz. j. pharm. sci ; 45(3): 527-537, July-Sept. 2009. graf, tab, ilus
Artigo em Inglês | LILACS | ID: lil-533181

RESUMO

This study investigated the α- and β-carotene content and provitamin A value of four leafy vegetables sold at local and street markets in Viçosa, MG, Brazil, in the spring and winter of 2002. Carotenoids were analyzed by high-performance liquid chromatography. α-Carotene was detected in all samples sold during spring, but was only present in a few samples of smooth and curly lettuce and kale in winter. β-Carotene was found in marked quantities in all leafy vegetables analyzed. Duncan's test (α = 5 percent) showed significantly higher α-carotene content in curly lettuce and vitamin A value in large-leaved watercress in the spring. Mean β-carotene content and vitamin A value were 7544, 8751, 2584, 2792, 8193, and 5338 μg/100 g and 666, 760, 227, 238, 698, and 460 μg RAE/100 g in large-leaved and hydroponic watercress, smooth and curly lettuce, kale and spinach, respectively. All leafy vegetables analyzed represent important sources of provitamin A and supply an important part of the daily requirements of children and adults.


Investigou-se o conteúdo de α e β-caroteno e avaliou-se o valor pro-vitamínico A de quatro hortaliças folhosas comercializadas em mercados locais e feira- livre de Viçosa, MG durante a primavera e o inverno de 2002. Os carotenóides foram analisados por Cromatografia Líquida de Alta Eficiência (CLAE). O α-caroteno foi detectado em todas as amostras analisadas na primavera, porém no inverno, somente algumas amostras de alface crespa e lisa, e couve apresentaram tal carotenóide. O β-caroteno foi encontrado, em quantidades apreciáveis, em todas as hortaliças folhosas analisadas. O teste de Duncan (α=5 por cento) detectou que o conteúdo de α-caroteno em alface crespa e o valor de vitamina A em agrião de folha larga foram estatisticamente superiores na primavera. Os teores médios de β-caroteno e de valor de vitamina A para agrião de folha larga e hidropônico, alface crespa e lisa, couve e espinafre foram: 7544; 8751; 2584; 2792; 8193; 5338 μg/100g e 666; 760; 227; 238; 698; 460 μg RAE/100g, respectivamente. Todas as hortaliças folhosas analisadas constituem importantes fontes de provitamina A e suprem grande parte das recomendações diárias de crianças e adultos.


Assuntos
Brasil , Carotenoides , Estações do Ano , Verduras , Vitamina A , Brassica , Brassicaceae , Cromatografia Líquida de Alta Pressão , Estruturas Vegetais , Spinacia oleracea
9.
Rev. biol. trop ; 56(3): 1053-1061, sep. 2008. graf, tab
Artigo em Espanhol | LILACS | ID: lil-637846

RESUMO

Experimental tolerance to boron of the plant species Nicotiana glauca, Jacaranda mimosifolia, Tecoma stans, Medicago sativa y Spinacea oleracea in Argentina. The activity of boron industries is a punctual and diffuse source of air, soil and water pollution. Therefore, it is a priority to study possible ways of reducing this impact. A relatively new technology for reducing soil pollution is phytoremediation, which uses plants and associate microorganisms. The first step in phytoremediation is to detect tolerant plant species, which is the objective of this work. A laboratory experiment to assess the germination, survival and growth of different species at different boron concentrations was carried out following a factorial design with two factors: plant species and boron concentration. Boron concentrations were determined at the beginning and the end of the experiment, taking into account substrates with and without vegetation. We found significant differences for treatment, species and the interaction species*treatment. N. glauca, M. sativa and J. mimosifolia were the most tolerant species. The other species had a decrease in the response variables, with the concentration of the pollutant. All the species had a low survival at the highest boron concentration. The reduction in boron concentration at the end of the experiment was higher in the 30 ppm treatment with M. sativa and the lower was registered in the 20 ppm treatment with J. mimosifolia and in 30 ppm with T. stans and S. oleraceae. We conclude that N. glauca, M. sativa and J. mimosifolia can be considered in remediation plans. Rev. Biol. Trop. 56 (3): 1053-1061. Epub 2008 September 30.


La actividad de las industrias borateras constituye una fuente puntual y difusa de contaminación del aire, suelo y aguas superficiales y profundas. Por lo tanto, el estudio y experimentación acerca de las posibles formas de contrarrestar este impacto constituye una prioridad. Una técnica relativamente nueva para descontaminar suelos es la fitorremediación, que emplea plantas y microorganismos asociados. El primer paso es detectar las especies vegetales tolerantes, lo que constituye el objetivo de este trabajo. Se realizó un experimento en laboratorio para evaluar la germinación, la supervivencia y el crecimiento de distintas especies en diferentes concentraciones de boro. Al comienzo y al final del experimento se determinó la concentración de boro en el sustrato para cada tratamiento y para sustratos con y sin vegetación. Se encontraron diferencias significativas debidas al tratamiento, la especie y la interacción especie *tratamiento. M. sativa, N. glauca y J. mimosifolia fueron las especies de mayor tolerancia al boro. Las otras especies presentaron una disminución en todas las variables-respuesta en función de la concentración del contaminante. Todas presentaron una baja supervivencia en la máxima concentración. La disminución de boro fue máxima en el tratamiento de 30 ppm de boro con M. sativa y la menor se registró en los tratamiento de 20 ppm de boro con J. mimosifolia y de 30 ppm de boro con T. stans y S. oleraceae. Se concluye que N. glauca, M. sativa y J. mimosifolia podrían considerarse como prometedoras en remediación.


Assuntos
Magnoliopsida/efeitos dos fármacos , Boro/toxicidade , Germinação/efeitos dos fármacos , Argentina , Magnoliopsida/crescimento & desenvolvimento , Bignoniaceae/efeitos dos fármacos , Bignoniaceae/crescimento & desenvolvimento , Recuperação e Remediação Ambiental/métodos , Medicago sativa/efeitos dos fármacos , Medicago sativa/crescimento & desenvolvimento , Spinacia oleracea/efeitos dos fármacos , Spinacia oleracea/crescimento & desenvolvimento , Fatores de Tempo , Tabaco/efeitos dos fármacos , Tabaco/crescimento & desenvolvimento
10.
Acta méd. costarric ; 45(1): 5-9, ene.-mar. 2003. ilus
Artigo em Espanhol | LILACS | ID: lil-403878

RESUMO

Las funciones que en el organismo humano ejercen los folatos referentes a la formación de eritrocitos y leucocitos en la médula ósea y a la prevención de daños en el desarrollo del tubo neural del niño durante la gestación, han sido bien estudiadas. En los últimos años se han venido identificando funciones relacionadas con la salud cardiovascuar y el desarrollo de enfermedad tumoral de los individuos. A este respecto, en esta revisión la autora pretende resaltar las funciones que ejercen los folatos en la salud humana, relacionadas con los niveles de homocisteína en suero y con la síntesis y preparación del ADN, lo cual ha sido relacionado respectivamente con el desarrollo de enfermedades cuardiovasculares y algunos tipos de cáncer en humanos. Descriptores: Folatos, ácido fólico, homocisteína, enfermedad cardiovascular, enfermedad tumoral.


Assuntos
Humanos , Ácido Fólico/administração & dosagem , Ácido Fólico/biossíntese , Ácido Fólico/fisiologia , Doenças Cardiovasculares , Dieta , Consumo de Alimentos , Brassica , Costa Rica , Fabaceae , Fígado , Spinacia oleracea
11.
Arch. latinoam. nutr ; 52(4): 355-361, dic. 2002.
Artigo em Espanhol | LILACS | ID: lil-356603

RESUMO

The purpose of this study was to evaluate the change in concentration of retinol and beta-carotene (BC) in blood serum and liver tissue of rats, after supplementation with synthetic BC and commonly consumed carotenoid-rich vegetables (carrot and spinach). Weanling male Wistar rats were randomly assigned in four groups of 16 rats each. The four groups of rats were supplemented according to the following feeding treatments: 1) Control group (0G), 0.2 mL corn oil; 2) Pure BC group (BCG), 60 micrograms RE in 0.2 mL corn oil; 3) Carrot group (CG), 60 micrograms RE in 0.2 mL corn oil; 4) Spinach group (SG), 60 micrograms RE in 0.2 mL corn oil. Analysis of retinol and BC contents in serum and liver was performed by HPLC procedures. The variance analysis showed no significant differences (a = 0.05) in the increase of weight of the animals and in the increase of retinol and BC levels in serum and in liver of the four treatments during the four weeks of supplementation. The correlation analysis between levels of retinol and BC in serum and in liver showed no relation between these two parameters. A regression analysis of liver BC levels in the four treatments showed the following slopes of the regression lines: BCG, 0.909; CG, 0.451; SG, 0.444, and 0G, 0.203. These results indicate that the highest BC absorption was in the BCG treatment, whereas the BC absorption in the CG and SG treatments was approximately one half.


Assuntos
Animais , Masculino , Antioxidantes/farmacocinética , Suplementos Nutricionais , Fígado/metabolismo , beta Caroteno/farmacocinética , Antioxidantes/análise , Disponibilidade Biológica , Daucus carota , Fígado/química , Ratos Wistar , Spinacia oleracea , Vitamina A/análise , Vitamina A/farmacocinética , beta Caroteno/análise
12.
Interciencia ; 27(9): 454-464, sept. 2002. tab, graf
Artigo em Espanhol | LILACS | ID: lil-338648

RESUMO

Se evaluó la concentración de metales y la de compuestos orgánicos foliares que pudiesen verse afectadas por el estrés causado por los primeros. Concentraciones fitotóxicas de metales pueden producir senescencia o inducir un proceso de desintoxicación. Se estudió la composición del suelo y, en las raíces y hojas se determinaron los nutrientes y las actividades de la fosfatasa ácida (AFA) y la nitrato reductasa (ANR). Se compararon dos plantas de cultivo, lechuga (L) y espinaca (S) con sus malezas asociadas Argeratum conyzoides (A) y A. houstoni-anum (H), en dos cultivos localizados en sitios cercanos a Caracas. San Antonio (Sitio 1) y San Pedro (Sitio 2). Los suelos en el Sitio 2 resultaron más ricos en K,Ca,P,Mg,Mn y Zn, más pobres en Ni, menos ácidos y más arenosos que los del Sitio 1. Las concentraciones de Al,Fe y Ca fueron altas en A y H, en comparación a plantas de cultivo, y el Cr resultó alto en H. Las hojas de A presentaron el mayor contenido de fenoles totales. Los valores más altos declorofila, carotenoides y peroxidación de lípidos se encontraron en H. Las mayores concentraciones de K,Mg,Mn,Cu y Zn las presentó S. Las concentraciones de Ni,Co,Pb y Cd resultaron bajas o no detectables en las cuatro especies de los dos sitios estudiados. En L se evaluaron también muestras procedentes de un cultivo hidropónico comercial, donde se observó una mejor nutrición que en las muestras cultivadas en suelo. Se concluye que las malezas presentaron mayores concentraciones de metales y de compuestos asociados al estrés oxidativo que las dos especies de cultivo


Assuntos
Cálcio , Clorofila , Meios de Cultura , Monoéster Fosfórico Hidrolases , Alface , Magnésio , Manganês , Metais , Nitrogênio , Ciências da Nutrição , Estresse Oxidativo , Spinacia oleracea , Controle de Plantas Daninhas , Zinco , Ciência , Venezuela
13.
Hig. aliment ; 14(74): 32-6, jul. 2000. tab, graf
Artigo em Espanhol | LILACS | ID: lil-265358

RESUMO

El objetovo es analizar el efecto combinado del ácido cítrico, el ácido ascórbico y el tipo de envase, sobre la calidad sensorial, la retención de clorofila y la pérdida de peso de espinaca mínimamente procesada, durante el almacenamiento refrigerado. Se propone desarrollar modelos matemáticos que permitan analizar y predecir el efecto de las concentraciones de ácido cítrico y ácido ascórbico, y del tiempo de almacenamiento sobre el desarrollo de off-odors, apariencia general, marchitamiento, amarronamiento y color.


Assuntos
Ácido Ascórbico , Ácido Cítrico , Conservação de Alimentos , Spinacia oleracea
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