Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
Mais filtros








Intervalo de ano de publicação
1.
Food Chem ; 182: 105-10, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-25842315

RESUMO

Acacia tortuosa produces a clear gum, very soluble in water. Previous reports showed that it was constituted by four fractions, one of them an arabinogalactan-protein complex. The elucidation of the A. tortuosa gum structure by the combination of classical chemical methods, size exclusion chromatography and NMR spectroscopy, was the objective of this investigation. The data obtained show that the heteropolysaccharide is an arabinogalactan type II, highly ramified, with lateral chains at C-2 as well as at C-6 of the galactose 3-O residues; mono-O-substituted galactoses were not detected. There are residues of mannose, the arabinose, pyranose predominantly, is terminal and 2-O-linked. The abundance of the 4-O-methyl-α-d-glucuronic acid was not previously reported. The proteic fraction is probably represented by an arabinogalactan-protein complex that binds poorly with ß-glucosyl Yariv reagent, and two glycoproteins. The NMR spectra suggest that the carbohydrate links to hydroxyproline through the galactose (galactosylation).


Assuntos
Acacia/química , Galactanos/química , Espectroscopia de Ressonância Magnética/métodos , Ácido Glucurônico , Glicoproteínas/química
2.
Invest Clin ; 52(2): 140-9, 2011 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-21866786

RESUMO

The seeds of Hymenaea courbaril (Caesalpiniace), a species widely disseminated in Venezuela, produce a clear and soluble gum. The dietetic fiber content (60.7%) of the gum was used as a good criterion for the formulation of integral bread in a diet for dyslipidemia patients. The proximal composition of the integral bread was determined. The product acceptability evaluation was done by a comparison test and by a hedonic scale. The experimental design was carried out with a total of 30 male volunteers with dyslipidemia. They were divided into two groups: Group A was fed with a modified diet, which included bread prepared with the H. courbaril gum; and Group B received the same diet without the gum, based on the American Dietetic Association recommendations. Both groups were maintained on their respective diets for six weeks. The lipid profile was determined in each patient, before starting the diets and after the specified period. The bread formula contained 17.60% protein, 1.19% fat and 0.97% crude fiber, in accordance with standards established by COVENIN. The paired preference test showed grater acceptance of the bread prepared with a gum concentration of 7% and low fat content. Significant decreases in the concentrations of triacylglycerol and VLDL-cholesterol were observed in Group A. These findings suggest a possible use of the H. courbaril gum, as a diet modifier for dyslipidemic patients.


Assuntos
Pão , Colesterol/sangue , Dislipidemias/sangue , Dislipidemias/dietoterapia , Alimentos Formulados , Hymenaea , Triglicerídeos/sangue , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença
3.
Kasmera ; 39(1): 18-25, ene.-jun. 2011. tab, graf
Artigo em Espanhol | LILACS | ID: lil-654005

RESUMO

El desarrollo de las levaduras del género Malassezia requiere condiciones especiales, estos hongos que producen afecciones en la piel, son generalmente cultivados en el medio Dixon. Se ensayaron los exudados gomosos de Spondias dulcis y Spondias mombin como sustratos para Malassezia furfur. Se evaluó también la producción de lipasa. Se determinó la cinética de crecimiento a un determinado intervalo de tiempo (0-168h), y a diferente concentración (0,5; 1%) y pH (4,5; 6,0). La biomasa obtenida para la levadura probada demostró que los sustratos preparados con los exudados gomosos son adecuados para su desarrollo. La mayor actividad de lipasa extracelular se observó al tiempo inicial de estudio (18h) en ambos sustratos, en las condiciones usadas: concentración (0,5 y 1%) y pH(4,5 y 6,0). Estas especies botánicas, ampliamente localizadas en Venezuela, especialmente en los Estados Zulia y Falcón, producen abundante goma. Este hecho, y los resultados obtenidos podrían ser útiles en la obtención de un nuevo sustrato, que pueda competir con el medio Dixon para el aislamiento y la caracterización de especies de Malassezia, y para la producción de lipasa


The development of genus Malassezia yeasts requires special conditions. This fungus, which produces skin diseases, is generally cultivated in the Dixon medium. Gum exudates from Spondias dulcis and Spondias mombin were tested as substrates for Malassezia furfur. Lipase production was also evaluated. The growth kinetic was determined for a given time range (0-168h) at different concentrations (0.5; 1%) and pH levels (4.5; 6.0). The biomass obtained for the tested yeast showed that substrates prepared with S. dulcis and S.mombin gum exudates are suitable for its development. The highest extracellular lipase activity was observed at 18h on both substrates at given concentrations (0.5; 1%) and pH (4.5; 6.0). These botanical species, widely located in Venezuela, especially in the States of Zulia and Falcon, yield abundant gum. Findings may be useful for obtaining new substrates that could compete with the Dixon medium for isolation and characterization of Malassezia species and for lipase production


Assuntos
Produção Agrícola , Anacardiaceae , Técnicas Microbiológicas/métodos , Malassezia/classificação , Malassezia/crescimento & desenvolvimento
4.
Invest. clín ; 52(2): 140-149, jun. 2011. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-664554

RESUMO

Hymenaea courbaril (Caesalpiniace), especie ampliamente diseminada en Venezuela, produce una goma clara y soluble en la semilla. El contenido de fibra dietética de la goma (60,7%) se usó como criterio para la formulación de un pan integral en la dieta para pacientes con dislipidemia. Se determinó la composición proximal del pan integral. La aceptabilidad del producto se evaluó por una prueba de comparación y por una escala hedónica. El diseño experimental, se hizo con una muestra de 30 voluntarios masculinos que presentaban dislipidemia. Se dividieron en dos grupos: el grupo A, se alimentó con una modificación de la dieta, que contenía un pan preparado con goma de H. courbaril, y el grupo B, recibió la dieta, sin la goma, con base en las recomendaciones de la Asociación Americana de Dietética (Control). Ambos grupos se mantuvieron en sus respectivas dietas durante 6 semanas. El perfil lipídico, se determinó en cada paciente, antes de iniciar la dieta y después del período señalado. El pan formulado, contenía 17,60% de proteínas; 1,19% de grasa y 0,97% de fibra cruda, de conformidad con lo establecido por las normas COVENIN. El Test de par de preferencia, demostró la mayor aceptación por el pan preparado con una concentración de goma al 7,0%, y un bajo contenido de grasa. Se produjo una disminución significativa en la concentración de triacilglicéridos y VLDL-colesterol en el grupo A. Estos hallazgos sugieren un posible uso de la goma de H. courbaril, como una modificación de la dieta, para pacientes con dislipidemia.


The seeds of Hymenaea courbaril (Caesalpiniace), a species widely disseminated in Venezuela, produce a clear and soluble gum. The dietetic fiber content (60.7%) of the gum was used as a good criterion for the formulation of integral bread in a diet for dyslipidemia patients. The proximal composition of the integral bread was determined. The product acceptability evaluation was done by a comparison test and by a hedonic scale. The experimental design was carried out with a total of 30 male volunteers with dyslipidemia. They were divided into two groups: Group A was fed with a modified diet, which included bread prepared with the H. courbaril gum; and Group B received the same diet without the gum, based on the American Dietetic Association recommendations. Both groups were maintained on their respective diets for six weeks. The lipid profile was determined in each patient, before starting the diets and after the specified period. The bread formula contained 17.60% protein, 1.19% fat and 0.97% crude fiber, in accordance with standards established by COVENIN. The paired preference test showed grater acceptance of the bread prepared with a gum concentration of 7% and low fat content. Significant decreases in the concentrations of triacylglycerol and VLDL-cholesterol were observed in Group A. These findings suggest a possible use of the H. courbaril gum, as a diet modifier for dyslipidemic patients.


Assuntos
Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Pão , Colesterol/sangue , Dislipidemias/sangue , Dislipidemias/dietoterapia , Alimentos Formulados , Hymenaea , Triglicerídeos/sangue , Índice de Gravidade de Doença
5.
Kasmera ; 36(1): 45-52, ene.-jun. 2008. graf, tab
Artigo em Espanhol | LILACS | ID: lil-517666

RESUMO

Las levaduras del género Malassezia son hongos que producen afecciones en la piel. El desarrollo de estos microorganismos requiere condiciones especiales. El medio Dixon es generalmente usado para su cultivo. Se ensayo el exudado gomoso de Spondias dulcis como sustrato para Malassezia furfur y Malassezia slooffiae en comparación con el medio Dixon. Se determino la cinética de crecimiento a un determinado rango de tiempo (0-120h), a diferentes concentraciones (1,2 por ciento) y pH (4,0;6,0;7,0). La relativa alta biomasa obtenida para las dos levaduras probadas demostró que el sustrato preparado con el exudado gomoso de S. dulcis es adecuado para su desarrollo. Spondias dulcis especie localizada en Venezuela produce abundante goma. Este hecho, y los resultados obtenidos podría ser útil para preparar un nuevo sustrato que pueda competir con Dixon para el aislamiento y la caracterización de especies de Malassezia.


Malassezia yeasts are fungi that produce skin affections. Growth of these microorganisms requires specific conditions. The Dixon medium has generally been used for their culture and has been tested. The use of Spondias gum as a substrate for Malassezia furfur and Malassezia slooffiae was tried and compared with the Dixon medium. The growth kinetic for a given time range(0-120 h) was determined at different concentrations (1.2 percent) and pH levels (4,0; 6,0;7,0). The relatively high biomass obtained for the two tested yeasts demonstrated that the substrate prepared with S. dulcis gum exudate is suitable for their growth. Spondias dulcis, a species located in Venezuela, yields abundant gum. This fact and the results discussed above indicate that it could be used to prepare a substrate that could compete with Dixon for isolating and characterizing the Malassezia species.


Assuntos
Anacardiaceae , Malassezia , Dermatopatias Infecciosas , Ciclização de Substratos
6.
Rev. cient. (Maracaibo) ; 18(1): 87-92, ene.-feb. 2008. tab
Artigo em Espanhol | LILACS | ID: lil-548655

RESUMO

Acacia glomerosa, Anterolobium cyclocarpum e Hymenaea courbaril, especies arbóreas ampliamente disemindas en Venezuela producen gomas con buen rendimiento. La mezcla de estas gomas se ensayó, como estabilizante en la preparación de helados de bajo contenido calórico. La viscosidad, el porcentaje de derretido y las propiedades sensoriales fueron determinados. Estas características físico-químicas se compararon con las exhibidas por los productos obtenidos con base en mezcla de gomas comerciales. La mezcla de gomas de las especies estudiadas incrementó la viscocidad del sistema, por lo tanto, favoreció una excelente incorporación y una distribución uniforme del aire; aportó textura y estabilidad durante el almacenamiento; mejoró la capacidad de expansión de la espuma y las propiedades de derretido. Por otra parte, aportó buenas características sensoriales, como la indica el alto puntaje alcanzado; apariencia (7.78), cremosidad (7.62), sabor (8.01) y bajo puntaje en presencia de cristales de hielo (3.06). Este trabajo evidenció la funcionalidad como estabilizante de la mezcla de gomas investigadas en la preparación de helados bajo en calorías.


Acacia glomerosa, Enterolobium cyclocarpum and Hymenaea courbaril, species widely disseminated in Venezuela, South America, produce gum with good yield. The mixture of these gums was tested as stabilizer in the low fat ice cream preparation. Viscosity, overrun, foam expansion, meltdown, shape factor and sensory properties were determined. These quality characteristics were compared with those exhibited by the product obtained with a mixture of commercial gums. The mixture tested provided the suitable viscosity for the ice cream mix with the corresponding overrun and texture. It gave better foaming properties and air incorporation. On the other hand, it was demonstrated the good sensory attributes by the highest score i.e. appearance (7.78), creaminess (7.62), flavor (8.01) and lowest score of iciness (3.06). This work showed good functionality as stabilizer of the mixture of gums investigated in the low fat ice cream preparation.


Assuntos
Bebidas Adoçadas Artificialmente , Goma Arábica , Gelados Comestíveis , Preparação em Desastres , Ciências da Nutrição
7.
Rev. cient. (Maracaibo) ; 15(1): 83-87, ene.-feb. 2005. tab
Artigo em Espanhol | LILACS | ID: lil-423498

RESUMO

Enterolobium cyclocarpum (Mimosaceae), especie localizada en Venezuela, produce goma con excelentes características físicio-químicas y alto rendimiento. Se evaluó la funcionalidad de esta goma como aditivo en la preparación de yogurt líquido semi-descremado. Cinco tratamientos fueron aplicados, control (sin goma) y otros a diferentes concentraciones de goma (0,05; 0,10; 0,15; 0,20 por ciento). Las características físico-químicas del producto (grasa, sólidos no grasos, acidez láctica, pH, viscosidad, sinéresis) y las propiedades sensoriales fueron investigadas. Se aplicó un análisis estadístico (ANOVA). El producto, obtenido con la mayor concentración de goma (0,20 por ciento) difiere estadísticamente (P<0,05) de aquellos obtenidos a las menores concentraciones de goma y del tratamiento control (sin goma). La goma ensayada (0,20 por ciento) proporcionó la viscosidad adecuada al yogurt, con bajo fenómeno de sinéresis y buena textura. Además, el producto exhibió los mejores atributos sensoriales, como lo indica el alto puntaje alcanzado: apariencia (6,98), sabor (7,12) textura (7,18) y aceptación (7,48). Estos resultados muestran una buena funcionalidad de la goma de E.cyclocarpum en la preparación de yogurt líquido semi-descremado


Assuntos
Aditivos Alimentares , Borracha , Viscosidade , Iogurte , Análise de Alimentos , Venezuela
8.
Carbohydr Res ; 338(7): 619-24, 2003 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-12644375

RESUMO

The tree Spondias dulcis, located in Venezuela, exudes a light-brown gum. The polysaccharide, isolated from the original gum, contains galactose, arabinose, mannose, rhamnose, glucuronic acid, and its 4-O-methyl derivative. Application of chemical methods, in combination with 1D and 2D NMR spectroscopy afforded interesting structural features of the gum polysaccharide. The unequivocal presence of rhamnose in the polymer structure was confirmed by chemical and spectral data [1H (1.03 ppm); 13C (16.92 ppm)]. Also confirmed was the existence of 3-O- and 6-O-substitutes galactose residues by the spectral data correlations observed in Heteronuclear Multiple Quantum Coherence (HMQC) and Heteronuclear Multiple Bond Correlation (HMBC). Also observed were unequivocal resonances for beta-D-glucuronic acid and its 4-O-methyl derivative, and the presence of 3-O-alpha-L-arabinofuranose and 3-O-beta-L-arabinopyranose residues.


Assuntos
Anacardiaceae/química , Galactanos/análise , Polissacarídeos/análise , Arabinose/análise , Configuração de Carboidratos , Sequência de Carboidratos , Cromatografia Líquida de Alta Pressão , Galactanos/química , Galactose/análise , Espectroscopia de Ressonância Magnética , Manose/análise , Dados de Sequência Molecular , Estrutura Molecular , Estruturas Vegetais/química , Polissacarídeos/química , Ramnose/análise , Xilose/análise
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA