RESUMEN
Apicomplexans are a group of pathogenic protists that cause various diseases in humans and animals that cause economic losses worldwide. These unicellular eukaryotes are characterized by having a complex life cycle and the ability to evade the immune system of their host organism. Infections caused by some of these parasites affect millions of pregnant women worldwide, leading to various adverse maternal and fetal/placental effects. Unfortunately, the exact pathogenesis of congenital apicomplexan diseases is far from being understood, including the mechanisms of how they cross the placental barrier. In this review, we highlight important aspects of the diseases caused by species of Plasmodium, Babesia, Toxoplasma, and Neospora, their infection during pregnancy, emphasizing the possible role played by the placenta in the host-pathogen interaction.
RESUMEN
Bee pollen has been reported to show antioxidant and radical scavenging activities; contributing to anti-inflammatory and gastroprotective properties. Venezuelan honeybee pollen has been little studied, but is consumed because its properties are known from other countries reports. On the basis of these reports, water, ethanol and methanol soluble fractions were prepared from dried bee-pollen commercially available and produced by La Montaña farm (Mérida, Venezuela). These fractions were evaluated for their functional properties, specifically, polyphenol content and total antioxidant activity. Pollen samples were separated by color in four fractions: yellow, brown, orange and ochre. Polyphenol content ranged between 396.7 to 1286.7 gallic acid equivalents GAE/100 g pollen; it was highest in pollen homogenates obtained with ethanol, followed by those obtained with methanol and water. The antioxidant activity ranged from 0.50 to 1.84 μmoles Trolox equivalents TEAC/100 g for water and ethanol homogenates respectively. The results presented in this work suggest that the ethanol extract of bee pollen show a potent antioxidant activity, comparable to human plasma, probably due to total polyphenol content of bee pollen. This is important because the bee pollen would be beneficial not only as a dietary supplement but also as a functional food.
Actividad antioxidante de polen apícola de Mérida, Venezuela, fraccionado en cuatro colores. Se ha reportado que el polen de las abejas tiene actividad antioxidante y secuestra radicales libres; relacionada con sus propiedades antiinflamatorias y gastroprotectivas. El polen apícola de Venezuela ha sido poco estudiado, pero se consume gracias a las propiedades conocidas por reportes provenientes de otros países. Tomando como base estos reportes, se prepararon fracciones solubles en agua, etanol y metanol del polen apícola seco comercialmente disponible y producido por la Granja La Montaña (Mérida, Venezuela). Estas fracciones fueron evaluadas en cuanto a sus propiedades funcionales, específicamente, contenido de polifenoles y la actividad antioxidante total. Las muestras de polen fueron separadas en cuatro fracciones de acuerdo al color: amarillo, marrón, naranja y ocre. El contenido de polifenoles se encontraba entre 396,7 a 1286,7 equivalentes de ácido gálico EAG/100 g de polen, y fue mayor en los homogenatos obtenidos con etanol, seguido por aquellos obtenidos con metanol y agua. La actividad antioxidante varió entre 0.50 a 1.84 μmoles equivalentes de Trolox TEAC/100 g par los homogenatos de agua y etanol respectivamente. Los resultados presentados en este trabajo sugieren los extractos de etanol de polen de abejas presentan una potente actividad antioxidante, comparable al plasma humano, probablemente debida a su contenido total de polifenoles. Esto es importante ya que el polen de abejas podría servir no solo como un suplemento alimenticio sino como una alimento funcional.
Asunto(s)
Animales , Antioxidantes/análisis , Abejas , Polen/química , Polifenoles/análisis , Análisis de Varianza , Antioxidantes/metabolismo , Polen/enzimología , Espectrofotometría , VenezuelaRESUMEN
Bee pollen has been reported to show antioxidant and radical scavenging activities; contributing to anti-inflammatory and gastroprotective properties. Venezuelan honeybee pollen has been little studied, but is consumed because its properties are known from other countries reports. On the basis of these reports, water, ethanol and methanol soluble fractions were prepared from dried bee-pollen commercially available and produced by La Montaña farm (Mérida, Venezuela). These fractions were evaluated for their functional properties, specifically, polyphenol content and total antioxidant activity. Pollen samples were separated by color in four fractions: yellow, brown, orange and ochre. Polyphenol content ranged between 396.7 to 1286.7 gallic acid equivalents GAE/100 g pollen; it was highest in pollen homogenates obtained with ethanol, followed by those obtained with methanol and water. The antioxidant activity ranged from 0.50 to 1.84 micromoles Trolox equivalents TEAC/100 g for water and ethanol homogenates respectively. The results presented in this work suggest that the ethanol extract of bee pollen show a potent antioxidant activity, comparable to human plasma, probably due to total polyphenol content of bee pollen. This is important because the bee pollen would be beneficial not only as a dietary supplement but also as a functional food.
Asunto(s)
Antioxidantes/análisis , Abejas , Polen/química , Polifenoles/análisis , Análisis de Varianza , Animales , Antioxidantes/metabolismo , Polen/enzimología , Espectrofotometría , VenezuelaRESUMEN
Banana and plane are the most important fruits in world trade, behind citric plants. In this work we studied the antioxidant capacity of banana and plane varieties of fruits obtained from interspecies crossed varieties of Musa acuminata and Musa balbisiana, named Harton plane, Cavendish banana, and Manzano banana. With this purpose we evaluated banana and plane crude extracts using the ferrous ion oxidation with xylenol orange method, the thiobarbituric acid method, determination of antioxidant activity, and effect on superoxide anion and hydroxyl radical and the radicals generated by ultraviolet light. The experiments showed that all extracts have the capacity to decrease the concentrations of lipid hydroperoxides and malondialdehyde, produced in the lipid peroxidation process, in a manner comparable to that of other widely studied antioxidants like melatonin and vitamin E. Moreover, all extracts had the capacity to inhibit the generation of superoxide anion, hydroxyl radical, and the radicals generated by ultraviolet light. When antioxidant activity was calculated, a value was found that was equivalent to a concentration of uric acid between 0.20 and 0.30 mM at the highest concentration of extract used, with uric acid being a potent antioxidant at 1 mM.
Asunto(s)
Antioxidantes/farmacología , Frutas/química , Musa/química , Extractos Vegetales/farmacología , Compuestos Ferrosos/química , Radicales Libres/química , Peróxido de Hidrógeno/farmacología , Radical Hidroxilo/química , Peroxidación de Lípido/efectos de los fármacos , NAD/farmacología , Oxidación-Reducción , Fenoles , Sulfóxidos , Superóxidos/química , Sustancias Reactivas al Ácido Tiobarbitúrico , Rayos Ultravioleta , Xilenos/químicaRESUMEN
The effect of Kraft black liquor on the lipid peroxidation of rat homogenates was examined. The lipid peroxidation of homogenates from different organs (kidney, brain, lung, and liver) was induced by Fenton's reagent. The products of lipid peroxidation, lipid hydroperoxides and TBARS were measured by FOX method and TBA assay, respectively. It was found that black liquor significantly reduced the concentration of TBARS, but not the concentration of lipid hydroperoxides. This inhibition was directly proportional to the concentration of Kraft black liquor and the incubation temperature. Conclusively, the black liquor from pulp and paper industry exhibited an antioxidant activity.
Asunto(s)
Antioxidantes/química , Lignina/química , Peroxidación de Lípido/efectos de los fármacos , Papel , Extractos de Tejidos/metabolismo , Residuos , Análisis de Varianza , Animales , Antioxidantes/farmacología , Peróxido de Hidrógeno , Hierro , Lignina/farmacología , Peróxidos Lipídicos/metabolismo , Ratas , Temperatura , Sustancias Reactivas al Ácido Tiobarbitúrico/metabolismoRESUMEN
One of the limitations of the biodegradation of hydrophobic chemical compounds, like lignins, is their low solubility in the aqueous solution where this process takes place. To resolve this problem, surfactants have been used to improve the solubility of these hydrophobic compounds. In this investigation, we studied the effect of surfactants (anionic, cationic, and non-ionic) on the treatment of Kraft black liquor with Fenton's reagent. In the Fenton reaction, H2O2 (two different concentrations, 10 mM and 20 mM), FeCl2 (1 mM) and surfactant solution (10%) were used. Black liquor degradation was determined by UV/Visible spectrophotometry and by measuring phenolic groups. In the presence of Fenton's reagent, the optimum conditions for the oxidative degradation of black liquor were 10 mM H2O2, 1 microL of 10% solution of anionic surfactant (SDS). The importance of the use of surfactants for preparing black liquor for subsequent Fenton's reagent-mediated degradation was discussed.