Acid phosphatases from beet root (Beta vulgaris) plasma membranes.

Several acid phosphatases (EC 3.1.3.2) were found in beet root (Beta vulgaris L.) plasma membranes. Two of them were partially purified by an extraction of plasma membranes with octylglucoside and successive gel-filtration and anion-exchange chromatographies. With p-nitrophenyl-phosphate (pNPP) as substrate, most of the phosphatase activity was found in a fraction containing an 82-kDa protein. This phosphatase showed an optimum pH of 5.4 and was inhibited by Cu(2+), Zn(2+), molybdate or vanadate. The other phosphatase had a lower specific activity with pNPP, but was able to dephosphorylate phospho-myelin basic protein (phospho-MBP). This phosphatase presented two polypeptides with molecular masses of 36 and 65 kDa and was 83% inhibited by 2 nM okadaic acid, which suggests it is a PP2A protein phosphatase. As the phosphatase activity was high in soluble (non-membrane) fractions, the possibility that phosphatases in plasma membranes were soluble contaminants was assessed. Following the method of Bérczi and Møller (Plant Physiol. 116:1029, 1998), it was found that about 45% of both acid and protein phosphatase activities could be due to soluble enzymes trapped inside membrane vesicles.

GABA and Dopamine Release from Different Brain Regions in Mice with Chronic Exposure to Organophosphate Methamidophos.

Organophosphates such as methamidophos, usually used in the agricultural field, have harmful effects on humans. Exposures to insecticides has been associated with many disorders, including damage to the central and peripheral nervous system. Chronic exposure to organophosphates may lead to persistent neurological and neurobehavioral effects. This study was conducted to determine the effect of methamidophos on [(3)H]-dopamine (DA) and gamma aminobutyric acid (GABA) release from different brain regions after chronic exposure to it for 3, 6 or 9 months. After a six-month methamidophos treatment, the mice showed high susceptibility to convulsive seizures and a reduction in stimulated gamma aminobutyric acid release from the cerebral cortex and hippocampal slices, whereas stimulated (DA) release was slightly decreased from the striatum after three months of methamidophos exposure. The results indicate changes in gamma aminobutyric acid and dopamine neurotransmission, suggesting a specific neuronal damage.

Partial characterization of the lectin of runner beans (Phaseolus coccieneus) var. Alubia.

We extracted and partial characterized lectin from runner beans (Phaseolus coccineus L.). This lectin shows a great affinity to fetuin-agarose column like others lectins and the electrophoretic gels point one band of approximately 45 kDa. In addition to the previous assays, we detected the presence of lectins by agglutination assays. We know that lectins are non-enzymatic proteins or glycoproteins that bind carbohydrates. The biological function of plant lectins is not fully understood, but they are hypothesized to be involved in a number of intrinsic processes. Many of those processes include hemagglutination. We believe that the P. coocineus lectin will be an important tool for know the properties of many lectins, included their capacity to detected and quantify tumor markers.

Alimento para niños preparado con harinas de maíz de calidad proteínica y garbanzo extruidos / Weaning food from quality protein maize and chickpea extruded flours / Alimento para crianças preparado com farinhas de milho de qualidade proteínica e grãos-de-bico extrusado

El presente estudio tuvo tres objetivos: 1) Determinar la mejor combinación de harina de maíz de calidad proteínica extruido (HME) y harina de garbanzo extruido (HGE) para producir un alimento para niños de alta calidad proteínica y elevada aceptabilidad sensorial, 2) formular el alimento infantil tipo atole a partir de la mezcla HME/HGE optimizada, y 3) evaluar las propiedades nutricionales de la mezcla HME/HGE optimizada y del alimento. Se aplicó la metodología de superficie de respuesta para determinar la combinación óptima HME/HGE. La mejor combinación HME/HGE fue 21,2:78,8%; esta mezcla tuvo contenidos (en materia seca) de 20,07% de proteína, 5,70% de lípidos y 71,14% de carbohidratos; su perfil de aminoácidos esenciales cubrió satisfactoriamente los requerimientos para niños de 2-5 años de edad recomendados por FAO/WHO, excepto para triptófano. El alimento infantil tipo atole derivado de esta mezcla tuvo un contenido de proteína de 4,52%, que es 14,4% de la energía del alimento, adecuado para un alimento para niños. Cada 100g de alimento infantil aportan 6,3-12,6% y 23,8-34,8% del requerimiento diario de energía y proteína para niños y niñas de 1-8 años de edad. El alimento infantil tuvo 62,1% de digestibilidad de la proteína in vitro, C-PER de 1,93 y calificación entre "me gusta mucho" y "me gusta extremadamente" en una prueba hedónica para aceptabilidad general. Este alimento podría utilizarse como alimento soporte del crecimiento infantil.

The present study had three objectives: 1) To determine the best combination of quality extruded protein maize flour (EMF) and extruded chickpea flour (ECF) for producing a weaning food of high quality protein and high sensory acceptability, 2) to make a kind of infant food (atole) with an optimal EMF/ECF blend, and 3) to evaluate the nutritional properties of the optimized EMF/ECF mixture and the weaning food. Response surface methodology was applied to determine the optimal EMF/ECF combination. The best EMF/ECF combination was 21.2:78.8%. This mixture contained (in dry matter) 20.07% protein, 5.70% lipids and 71.14% carbohydrates; its essential amino acids (EAA) profile satisfactorily covered the requirements for children 2-5 years old recommended by FAO/WHO, except for tryptophan. The atole-type weaning food prepared with the optimized mixture had a protein content of 4.52%, which accounts for 14.4% of the supplied energy, suitable for a weaning food. Each 100g of the weaning food supply, respectively, 6.3-12.6% and 23.8-34.8% of the daily energy and protein requirements for children 1-8 years old. The weaning food had a 62.1% protein digestibility in vitro, a C-PER of 1.93, and was evaluated between "very liked" and "extremely liked" in a hedonic test for overall acceptability. This food could be used to support the growth of infants.

O presente estudo teve três objetivos: 1) Determinar a melhor combinação de farinha de milho de qualidade proteínica extrusado (HME) e farinha de grão-de-bico extrusado (HGE) para produzir um alimento para crianças de alta qualidade proteínica e elevada aceitabilidade sensorial, 2) formular o alimento infantil tipo mingau a partir da mistura HME/HGE otimizada, e 3) avaliar as propriedades nutricionais da mistura HME/HGE otimizada e do alimento. Aplicou-se a metodologia de superfície de resposta para determinar a combinação ótima HME/HGE. A melhor combinação HME/HGE 21,2:78,8%; esta mistura teve conteúdos (em matéria seca) de 20,07% de proteína, 5,70% de lipídios e 71,14% de carboidratos; seu perfil de aminoácidos essenciais cobriu satisfatoriamente os requerimentos para crianças de 2-5 anos de idade recomendados por FAO/WHO, exceto para triptófano. O alimento infantil tipo mingau derivado desta mistura teve um conteúdo de proteína de 4,52%, que é 14,4% da energia do alimento, adequado para um alimento para crianças. Cada 100g de alimento infantil aportam 6,3-12,6% e 23,8-34,8% do requerimento diário de energia e proteína para meninos e meninas 1-8 anos de idade. O alimento infantil teve 62,1% de digestibilidade da proteína in vitro, C-PER de 1,93 e qualificação entre "gosto muito" e "gosto demasiado" em uma prova hedônica para aceitabilidade general. Este alimento poderia utilizar-se como alimento suporte do crescimento infantil.