Antioxidant activity of four color fractions of bee pollen from Mérida, Venezuela

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.

Antioxidant activity of four color fractions of bee pollen from Mérida, Venezuela.

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.

Properties of honey from ten species of Peruvian stingless bees.

Honey produced by ten stingless bee species (Melipona crinita, M. eburnea, M. grandis, M. illota, Nannotrigona melanocera, Partamona epiphytophila, Ptilotrigona lurida, Scaptotrigona polystica, Scaura latitarsis, and Tetragonisca angustula) from Peru has been characterized according to traditional physicochemical standards (color and moisture), biochemical components (flavonoids, polyphenols, nitrites, proteins), and bioactive properties (antibacterial activity, antioxidant capacity). Analytical data are also provided for a sample of Apis mellifera and an artificial honey control. For stingless bees, honey color varied between 26 and 150 mm Pfund. M. illota produced the lightest honey, while N. melanocera and T. angustula were the darkest. Moisture varied between 20.8 and 45.8 g water/100 g, confirming higher moisture for stingless bee honey than the A. mellifera honey standard of 20 g water/100 g. Flavonoids varied from 2.6 to 31.0 mg quercetin equivalents/100g, nitrites from 0.30 to 2.88 micromoles nitrites/100 g, polyphenols from 99.7 to 464.9 mg gallic acid equivalents/100g, proteins from 0.75 to 2.86 g/100 g, and the antioxidant capacity from 93.8 to 569.6 micromoles Trolox equivalents/100 g. The minimal inhibitory concentration (MIC) was slightly lower against Staphylococcus aureus (12.5 -50 g/100 mL) than Escherichia coli (50 g/100 mL).

Antioxidant capacity of Venezuelan honey in wistar rat homogenates.

The antioxidant effect of several polyphenolic compounds is well known. However, little is known about the antioxidant capacity of Venezuelan honey, which has a high content of polyphenolic compounds. In this work, the antioxidant capacity of a genuine honey produced in Mérida, Venezuela was studied using the ferrous iron oxidation with xylenol orange method, the thiobarbituric acid method, and the determination of antioxidant activity. We found that this honey has the capacity to decrease significantly the concentration of lipid hydroperoxides and malondialdehyde, produced during the lipid peroxidation process, in a comparable way with other widely studied antioxidants such as melatonin and vitamin E. It was found that the antioxidant activity in the 50% honey dilution, the highest concentration we tested, was equivalent to a concentration of uric acid of 0.62 mM.

Antioxidant capacity of crude extracts from clones of banana and plane species.

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.