Effects of Solar Drying on the Structural and Thermodynamic Characteristics of Bee Pollen / Efectos del secado solar sobre las características estructurales y termodinámicas del polen apícola

Background: Bee pollen is a natural product collected and transformed by bees, intended for human consumption, given its nutritional and bioactive richness. The fundamental operation of adequacy is drying, which allows its preservation, avoiding chemical or microbiological degradation, typically using tray dryers with hot air that use electricity or fuel for heat generation. Solar drying is an alternative that uses radiation as an energy source. However, it should be ensured that this type of process guarantees the quality of the product while not degrading its properties and, therefore, maintaining its morphological integrity. Objective: to establish the effect of solar drying on bee pollen structure compared to the conventional cabin dehydration process. Methods: Bee pollen was dehydrated using two types of dryers: a solar dryer and a forced convection oven. The solar dryer operating conditions were an average temperature of 19-35 °C with a maximum of 38 °C and average relative humidity (RH) of 55 %. Cabin dryer operating conditions were a set point temperature of 55 ± 2 °C and 10 % RH average humidity. The morphologic and thermodynamic properties of dried bee pollen, such as phase transition enthalpy through Differential Scanning Calorimetry (DSC), porosity and surface area through surface area analysis, and microscopic surface appearance by Scanning Electron Microscopy (SEM), were measured. Results: The results showed dry bee pollen, both in the cabin dryer and solar dryer, did not suffer morphological changes seen through SEM compared to fresh bee pollen. Moreover, surface area analysis indicated the absence of porosity in the microscopic or macroscopic structure, demonstrating that solar or cabin drying processes did not affect the specific surface area concerning fresh bee pollen. Additionally, Differential Scanning Calorimetry (DSC) and Thermo Gravimetric Analysis (TGA) showed that endothermic phase transitions for dried bee pollen by cabin or solar dryer were at 145 °C and 160 °C, respectively. This can be mostly associated with free water loss due to the morphological structure preservation of the material compared to fresh bee pollen. Conclusion: These results demonstrate that solar drying is a reliable alternative to bee pollen dehydration as there were no effects that compromised its structural integrity

Antecedentes: El polen apícola es un producto natural recolectado y transformado por las abejas. La operación fundamental de adecuación del polen es el secado, lo que permite su conservación, evitando su degradación química o microbiológica, típicamente se utilizan secadores de bandejas con aire caliente que emplean electricidad o combustibles para la generación de calor. El secado solar es una alternativa que utiliza la radiación solar como fuente de energía. Sin embargo, se debe garantizar que este tipo de proceso asegure la calidad del producto a la vez que no degrade sus propiedades, manteniendo su integridad morfológica. Objetivo: Establecer el efecto del secado solar sobre la estructura del polen apícola en comparación al proceso convencional de deshidratación en cabina. Métodos: El polen de abeja se deshidrató utilizando dos tipos de secadores: secador solar y horno de convención forzada. Las condiciones de operación del secador solar fueron una temperatura promedio de 19-45 °C con un máximo de 38 °C y una humedad relativa (HR) promedio de 55 %. Las condiciones de operación del secador de cabina fueron una temperatura de referencia de 55 ± 2 °C y una humedad promedio de 10 % HR. Se midieron las propiedades morfológicas y termodinámicas del polen de abeja desecado, como la entalpía de transición de fase mediante calorimetría diferencial de barrido (DSC), la porosidad y el área superficial mediante análisis de área superficial y el aspecto microscópico de la superficie mediante microscopía electrónica de barrido (SEM). Resultados: Los resultados mostraron que el polen seco tanto en el secador de cabina como en el secador solar muestra que no sufrió cambios morfológicos vistos a través de Microscopía Electrónica de Barrido y en comparación con el polen fresco de abeja, además un análisis de sortometría indicó la ausencia de porosidad en la estructura microscópica y macroscópica, lo que indica que los procesos de secado solar o en cabina no tuvieron efectos sobre el área superficial específica con respecto al polen fresco de las abejas. En adición, los resultados de calorimetría diferencial de barrido (DSC) y análisis termogravimétrico (TGA) muestran que las transiciones de fase endotérmicas para el polen seco tanto en secado de cabina como solar fueron a 145 °C y 160 °C, que puede asociarse mayormente a la pérdida de agua libre, debido a la conservación de la estructura morfológica del material y en comparación al polen fresco. Conclusión: Estos resultados demuestran que el secado solar es una alternativa viable para la deshidratación del polen al no existir efectos que comprometan su integridad estructural

Combined effects of bee pollen supplementation and resistance training on aerobic capacity, muscular performance, antioxidant status, and bone metabolism markers in young men: A randomised controlled trial

@#Introduction: This study investigated the combined effects of bee pollen and resistance training on aerobic capacity, muscular performance, antioxidant status, and bone metabolism markers among young men. Methods: Forty young men were randomly assigned into four groups: sedentary control (C), bee pollen supplementation (BP), resistance training (RT), and combined bee pollen supplementation and resistance training (BPRT) groups. Bee pollen was consumed by participants in BP and BPRT groups (1500 mg daily for eight weeks). Resistance training was performed thrice per week for eight weeks in RT and BPRT groups. Participants’ anthropometry, aerobic capacity, isokinetic muscular peak torque (strength), and average power were measured. Concentrations of serum total antioxidant status (TAS), serum superoxide dismutase (SOD), serum alkaline phosphatase (ALP), and serum C-terminal telopeptide of type 1 collagen (1CTP) were determined. Results: After eight weeks of intervention, there was a significant decrease in 1CTP in BP group. In RT group, significant increases were observed in both muscular strength and power. In BPRT group, significant increases in both muscular strength and power, and a significant decrease in 1CTP were observed after 8 weeks. There were no significant changes in aerobic capacity, serum TAS, SOD, and ALP in all the study groups. Conclusion: Resistance training using dumbbells and elastic bands seemed to elicit beneficial effects on muscular strength and power, while bee pollen supplementation alone reduced the level of bone resorption marker. In addition, combining bee pollen with resistance training seemed to offer additive benefit in muscular strength and power.

Caracterización microbiológica de polen seco y congelado en Viracachá-Colombia

RESUMEN Objetivo. Caracterizar microbiológicamente el polen seco y congelado producido en el municipio de Viracachá-Boyacá. Materiales y métodos. A través de un estudio transversal descriptivo cuantitativo se tomaron muestras de 5 apiarios, cada uno con 10 colmenas, separando el polen en seco y congelado, determinando para cada muestra: aerobios mesófilos, coliformes totales, coliformes fecales, Staphylococcus aureus, Clostridium sulfito reductor y hongos. Los datos obtenidos se analizaron de acuerdo a normatividades internacionales y se compararon con resultados de investigaciones en otros países. Resultados. Se encontraron coliformes totales y fecales en tres de los cinco apiarios evaluados y solo en muestras de polen seco. Además, en dos apiarios cuando se analizó polen seco se encontró Staphylococcus aureus. Los resultados microbiológicos de la mayoría de las muestras se encuentran dentro de los rangos de algunas normatividades internacionales, sin embargo, los mejores resultados en cuanto a calidad microbiológica se determinaron para el polen congelado. Conclusiones. El proceso de congelamiento del polen ofrece ventajas relativas al mantenimiento de la calidad microbiológica en comparación con el proceso de secado. Se hace necesario evaluar la calidad microbiológica de ambos productos a través del tiempo de almacenamiento.

ABSTRACT Objective. Microbiologically characterize dry and frozen pollen produced in the municipality of Viracachá-Boyacá. Materials and methods. Through a quantitative descriptive cross-sectional study, samples from 5 apiaries were taken, each with 10 hives, separating the pollen dry and frozen, determining for each sample: mesophilic aerobes, total coliforms, fecal coliforms, Staphylococcus aureus, Clostridium sulfite reducer, and fungus. The data obtained were analyzed according to international regulations and compared with research results in other countries. Results. Total and fecal coliforms were found in three of the five apiaries evaluated and only in dried pollen samples. Also, in two apiaries when dry pollen was analyzed, Staphylococcus aureus was found. The microbiological results of most samples are within the ranges of some international regulations; however, the best results in terms of microbiological quality were determined for frozen pollen. Conclusions. The pollen freezing process offers advantages related to maintaining microbiological quality compared to the drying process. It is necessary to evaluate the microbiological quality of both products throughout the storage time.

Composition, biological activity and toxicity of bee pollen: state of the art / Composición, actividad biológica y toxicidad del polen apícola: estado-del-arte

A research was conducted in scientific databases using keywords related to the composition, biological activity and toxicity of bee pollen from 2007 to July 2017. It was verified that this product is rich in carbohydrates, proteins and lipids, as well as various minerals and phenolic compounds. Its functional biological properties can be attributed mainly to the high content of flavonoids and polyphenols and a considerable antioxidant capacity has been reported, also highlighting antimicrobial activity and against cancer. However, current research still lacks deeper experimental evidence to justify the use of bee pollen for these purposes. The potential risks of their consumption can be attributed to contamination by pesticides, heavy metals and due to their allergenicity. A search of patents executed in technological databases with respect to the main properties of bee pollen has demonstrated a high interest in the development of technological products based on its many applications. The number of articles and patents found with this theme highlights the importance of this natural product in the scientific-technological advance, focusing on the development of natural supplements.

Há sido realizada una investigación en bases de datos científicas utilizando palabras clave relacionadas a la composición, actividad biológica y toxicidad del polen apícola en el período de 2007 a julio de 2017. Se ha verificado que este producto es rico en carbohidratos, proteínas y lípidos, además de diversos minerales y compuestos fenólicos. Sus propiedades biológicas funcionales pueden ser atribuidas principalmente al alto contenido de flavonoides y polifenoles y se ha reportado una considerable capacidad antioxidante, con destaque también para la actividad antimicrobiana y contra el cáncer. Sin embargo, las investigaciones actuales todavía carecen de evidencias experimentales más profundas para justificar el uso del polen apícola para estos propositos. Los riesgos potenciales de su consumo pueden ser atribuidos en gran parte a la contaminación por pesticidas, metales pesados y debido a su alergenicidad. Una búsqueda de patentes realizada en bases de datos tecnológicas con relación a las principales propiedades del polen apícola ha revelado un alto interés en el desarrollo de productos tecnológicos con base en sus diversas aplicaciones. La cantidad de artículos y patentes encontrados con ese tema evidencia la importancia de ese producto natural en el avance científico y tecnológico, con enfoque para el desarrollo de suplementos naturales.

Physicochemical parameters and content of B-complex vitamins: an exploratory study of bee pollen from southern Brazilian states / Parámetros físico-químicos y contenido de vitaminas del complejo B: un estudio exploratorio del polen apícola del sur de Brasil

ABSTRACT This study aimed to determine the presence of B-complex vitamins and some physicochemical parameters in bee pollen samples from the southern Brazilian states of Paraná, Santa Catarina and Rio Grande do Sul and, then, to identify their correlations with the geographical and botanical origin of the samples using multivariate statistical techniques. B-complex vitamins were determined by HPLC and mean contents were 0.79 mg/100 g (vitamin B1), 0.88 mg/100 g (vitamin B2), 5.31 mg/100 g (sum of vitamin B3 vitamers) and 4.42 mg/100 g (sum of B6 vitamers). The physicochemical parameters of the samples were consistent with those reported in the literature. The results showed that bee pollen is an important source of B-complex vitamins and multivariate statistical exploratory techniques suggested its nutritional content should be evaluated locally.

RESUMEN El objetivo de este estudio fue determinar la presencia de vitaminas del complejo B y algunos parámetros físico-químicos en muestras de polen apícola oriundas de los Estados del Sur de Brasil (Paraná, Santa Catarina y Rio Grande do Sul); y correlacionar estos resultados con el origen botánico y geográfico, usando un análisis estadístico multivariado. Las vitaminas del complejo B fueron determinadas por HPLC y su contenido fue de 0,79 mg/100 g (vitamina B1); 0,88 mg/100 g (vitamina B2); 5,31 mg/100 g (suma de los compuestos de vitamina B3); y 4,42 mg/100 g (suma de los compuestos de vitamina B6). Los parámetros físico-químicos de las muestras fueron consistentes con los reportados en la literatura. Los resultados mostraron que el polen apícola fue una fuente importante de vitaminas del complejo B, y las técnicas multivariadas sugirieron que su contenido nutricional debe ser evaluado localmente.

Analysis of the effects of climate variables on Apis mellifera pollen foraging performance / Análise dos efeitos de variáveis climáticas no desempenho de forrageamento de pólen de abelhas Apis mellifera

Pollination services performed by bees are essential for the reproduction of a great part of flowering plants. The pollen collected by Apis mellifera while performing pollination (bee pollen), has been incorporated into the human diet for its favorable nutritional components. Around 1,500 tons of bee pollen are produced annually worldwide, especially in Spain, China, Australia, Argentina, and Brazil. Despite the importance of bee pollen within apiculture, little is known about the effects of climate variations on bee pollen collection and production. We monitored the pollen collection performance of 24 different honey bee colonies in different climate conditions within a period of one year. We then analyzed the statistical interaction among the number of worker bees returning with pollen loads and 12 climatic variables, to produce a predictive mixed linear model. The results obtained showed that 7 climatic variables were statistically correlated to the pollen collection observed: Maximum temperature of the day, minimum temperature of the day, dew point temperature, relative humidity, cloud cover, rainfall, and the date of the sample. This research brings information for the development of a more effective pollen productive system.(AU)

Serviços de polinização são essenciais para a reprodução de uma grande parte das plantas com flores. Além de fundamental para produtividade agrícola e segurança alimentar no planeta, a atividade de polinização por Apis mellifera também possibilita a produção do pólen apícola. Devido a sua riqueza nutricional, o pólen apícola vem sendo incorporado às dietas humanas e de animais de interesse zootécnico. Cerca de 1.500 toneladas de pólen de abelha são produzidas anualmente em todo o mundo, especialmente em países como Espanha, China, Austrália, Argentina e Brasil. Apesar da importância do pólen na cadeia produtiva apícola, muito pouco se conhece sobre os efeitos das variações climáticas sobre a coleta e a produtividade de pólen. Neste estudo, foi monitorado o desempenho da coleta de pólen de 24 colônias de abelhas africanizadas, em diferentes condições climáticas, por um período de um ano. Analisaram-se estatisticamente as interações dos dados obtidos para o número de abelhas operárias que retornaram com cargas de pólen nas corbículas e 12 variáveis climáticas, a fim de se produzir um modelo estatístico preditivo. Os resultados obtidos mostraram que sete variáveis climáticas influenciaram significativamente a coleta de pólen: temperatura máxima do dia, temperatura mínima do dia, temperatura do ponto de orvalho, umidade relativa, cobertura de nuvens, precipitação pluviométrica e data da amostragem. Esta pesquisa traz informações importantes para o desenvolvimento de um sistema produtivo de pólen apícola mais eficaz.(AU)

Differential performance of honey bee colonies selected for bee-pollen production through instrumental insemination and free-mating technique / Comparação do desempenho de colônias de abelhas melíferas selecionadas para maiores produções de pólen apícola, por meio de inseminação instrumental e acasalamento livre

The use of bee-pollen as a nutritional supplement or as a production-enhancing agent in livestock has increased the demand for this product worldwide. Despite the current importance of this niche within the apiculture industry, few studies have addressed the pollen production. We tested the performance of free-mated (FM) and instrumentally inseminated queens (IQ) in order to establish the effect of different breeding systems on pollen production. The F1 generation of IQ queens produced 153.95±42.83g/day, showing a significant improvement on the pollen production (2.74 times) when compared to the parental generation (51.83±7.84g/day). The F1 generation of free-mated queens produced 100.07±8.23 g/day, which increased by 1.78 times when compared to the parental generation. Furthermore, we observed a statistically significant difference between the pollen production between colonies from the IQ and FM treatments. This study suggests that inseminated queens should be considered by beekeepers that aim to increase pollen production.(AU)

O uso do pólen apícola como suplemento nutricional humano e animal tem aumentado significativamente a demanda por este produto em todo o mundo. Apesar da importância atual desse nicho dentro da apicultura, poucos estudos têm abordado melhorias no sistema produtivo de pólen. Testamos o desempenho de rainhas fecundadas através de acasalamento livre (FM) e inseminação instrumental (QI), a fim de analisar o efeito de diferentes técnicas de melhoramento genético no ganho produtivo de pólen apícola. A geração F1 de rainhas QI produziu 153,95±42,83g de pólen por dia, mostrando uma melhora significativa na produção (2,74 vezes) quando comparado à geração parental (51,83±7,84g/dia). A geração F1 de rainhas de livre acasalamento produziu 100,07±8,23g/dia, o que significou um aumento de 1,78 vezes. Além disso, observou-se uma diferença estatisticamente significativa entre a produção de pólen entre as colônias dos tratamentos QI e FM. Este estudo sugere que a técnica de inseminação instrumental deve ser incorporada nos sistemas produtivos de pólen apícola brasileiro.(AU)

Bee pollen extract of Malaysian stingless bee enhances the effect of cisplatin on breast cancer cell lines

Objective: To evaluate the antioxidant and antiproliferative effect of methanolic bee pollen extract (BPE) of Malaysian stingless bee [Lepidotrigona terminata (L. terminata)] and its synergistic effect with cisplatin (a chemotherapeutic drug) on MCF-7 cancer cell line. Methods: The antioxidant activity of BPE from L. terminata was measured by using 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) assay. Antiproliferative activity at different concentrations of BPE and cisplatin was determined through using MTT assay on MCF-7 and L929 cell lines. An interaction effect (synergistic, additive and antagonistic) between BPE and cisplatin was determined by CompuSyn software based on MTT assay data. Results: The EC

Microorganisms in Vacuum Stored Flower Bee Pollen

Contamination with sanitary microorganisms from Enterobacteriaceae, Pseudomonadaceae, Staphylococcaceae, Micrococcaceae and Bacillaceae families in flower bee pollen from Bulgaria after one-year vacuum-packed cold storage has been found. Dried flower bee pollens intended for human consumption were with high incidence rate of contamination with Pantoea sp. (P. agglomerans and P. agglomerans bgp6) (100%), Citrobacter freundii (47%), Proteus mirabilis (31.6%), Serratia odorifera (15.8%) and Proteus vulgaris (5.3%). Bee pollens were also positive for the culture of microorganisms from Staphylococcaceae, Micrococcaceae and Bacillaceae families: Staphylococcus hominis subsp hominis, Staphylococcus epidermidis, Arthrobacter globiformis, Bacillus pumilis, Bacillus subtilis and Bacillus amyloliquefaciens. It was concluded that, if consumed directly, the vacuum-packed cold stored dried bee pollen, harvested according hygienic requirements from bee hives in industrial pollution-free areas without intensive crop production, is not problem for healthy human.

Acrylic hydrogels modified with bee pollen for biomedical applications.

The focus of this paper is to present the effect of bee pollen on the structure and properties of acrylic hydrogels, often used as materials for wound dressings. Honey, propolis and bee pollen have been very well known for their extraordinary healing and medical properties for thousands of years. Ancient Egyptians, Greeks and Romans have reportedly used bee pollen as a drug, especially for a number of skin diseases and lesions. Acrylic hydrogels are, on the other hand, rather recently discovered materials used for novel wound dressings. The idea of our research was to combine a synthetic polymer matrix with bee pollen, in order to obtain innovative materials which could be used as wound dressings exhibiting new properties. The obtained acrylic hydrogels containing bee pollen were investigated towards swelling ability in distilled water and different fluids, including pseudo-extracellular fluid, simulated body fluid and Ringer’s solution. Moreover, incubation in water and simulated body fluids (SBF) and Ringer’s solution was carried out. The morphologies of bee pollen and obtained acrylic hydrogels modified with bee pollen were characterized by means of scanning electron microscopy (SEM). The chemical structure of the polymer matrix was confirmed by ATR-FT-IR spectra.