ABSTRACT
This paper proposes to apply a postharvest environmental stress to red apples, Malus domestica, variety Red Delicious in order to increase the polyphenols compounds (PP) content in their peels. The possibility of enhancing extractable PP provides a useful alternative for the use of discarded crops in the food industry. A great increase in PP was observed in response to light damage produced by the environmental stress applied in this work. Flavonols > anthocyanins > flavanols > dihydrochalcones > phenolic acids is the order in PP content. The interaction of the extracted PP from unstressed and stressed apple peels with beta-lactoglobulin (ß-LG) was characterized. A PP/ß-LG complex which was formed with one single binding site in the protein was determined. The interaction was spontaneous and enthalpy driven. PP extracted from unstressed samples had greater affinity for the protein than PP extracted from stressed samples, possibly due to the polar characteristic of anthocyanins. The results of this last study could provide a better understanding of the interaction between PP and ß-LG to incorporate them into functional foods.
ABSTRACT
Colonic effects of extruded whole-grain sorghum diets were evaluated using a model of growing rats. In all, twenty-four male Wistar rats were fed control (C), extruded white sorghum (EWS) or red sorghum (ERS). Consumption of sorghum diets showed satiety properties, with reduction of caecal pH, and lower activity of ß-glucosidase and ß-glucuronidase enzymes. Decreased copper zinc superoxide dismutase and manganese superoxide dismutase and increased catalase and glutathione peroxidase levels were observed in colonic mucosa. The induction of antioxidant enzymes occurred through the activation of the nuclear factor erythroid 2-related factor 2 protein and its subsequent translocation into the nucleus. ERS was able to decrease the proliferation of proximal mucosa of colon, demonstrating a possible effect against colorectal tumourigenesis. EWS increased proliferation and also apoptosis, ensuring the re-establishment of homoeostasis of the colonic mucosa. No antioxidant systemic effect (serum or hepatic level) was observed. It is likely that despite the extrusion the low bioavailability of the phenolic compounds of sorghum diets caused them to exert mainly acute effects at the colon level. Extruded whole-grain sorghum is a good functional ingredient that might be promising in dietary prevention of intestinal diseases.
Subject(s)
Colon/metabolism , Diet , Sorghum/chemistry , Whole Grains/chemistry , Animals , Catalase/metabolism , Disease Models, Animal , Glucuronidase/metabolism , Glutathione Peroxidase/metabolism , Hydrogen-Ion Concentration , Intestinal Diseases/prevention & control , Intestinal Mucosa/metabolism , Male , NF-E2-Related Factor 2/genetics , NF-E2-Related Factor 2/metabolism , Rats , Rats, Wistar , Satiation , Superoxide Dismutase/metabolism , beta-Glucosidase/metabolismABSTRACT
Introducción: el alfajor es uno de los productos más activo del mercado de las golosinas y se encuentra en la alimentación cotidiana de la población Argentina, existiendo modificados para personas con diversas patologías, como es el caso de los alfajores dietéticos de bajo valor glucídico. Objetivos: evaluar -a través del rotulado nutricional- la cantidad de grasas totales, ácidos grasos saturados (AGS) y sodio presentes en los alfajores dietéticos de bajo valor glucídico de la ciudad de Rosario. Materiales y métodos: se analizaron y categorizaron los alfajores de acuerdo al Código Alimentario Argentino (CAA) y el Sistema del Semáforo Nutricional. Resultados: según el CAA los alfajores se clasificaron para grasas totales: 27% "bajo contenido" y ninguno "no contiene"; para AGS: 13% "bajo contenido", 34% "no contiene"; y para sodio: 13% "bajo contenido", 7% "muy bajo contenido" y ninguno "no contiene". Para todos los nutrientes, la mayoría de los alfajores no fue posible categorizar por exceder su contenido la clasificación del CAA. Según la metodología del Semáforo los alfajores presentaron para grasas totales: 27% "bajo contenido" y 73% "mediano contenido"; para AGS: 47% "bajo contenido", 20% "mediano contenido" y 33% "alto contenido"; y para sodio: 20% "bajo contenido" y 80% "mediano contenido". Conclusiones: ningún alfajor cumplió con los requisitos nutricionales para clasificarlo como adecuado; el 67% se clasificó como medianamente adecuado y el 33% como no adecuado. Según el CAA, la mayoría de los alfajores no se pudo clasificar por no estar contemplado su alto contenido en los nutrientes analizados.
