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- Mixture of bee bread with honey: nutritional and microbiological characterizationPublication . Fortes, Adriana; Tomás, Andreia; Rodrigues, Paula; Vilas-Boas, Miguel; Martins, Vitor Manuel RamalheiraBeebread is a hive product produced in the honeycomb, through the lactic fermentation of pollen collected and partially processed by bees. This hive product has a chemical composition that makes it an interesting product, not only because of its nutritional value, but also related with its biological properties, such as antiinflammatory, anticancer, antinociceptive, and antidiabetic. In fact, beebread has earned some attention from the scientific community, being reported as a functional food with nutritional benefits, healing and preventive effects of some diseases.
- Structural features and macrophage immunostimulatory activity of the polysaccharides from Fraxinus angustifolia and Mentha suaveolens hot water extractsPublication . Martins, Vitor Manuel Ramalheira; Simões, Joana; Ferreira, Isabel; Cruz, Maria T.; Domingues, Maria R.M.; Coimbra, Manuel A.The dried leaves of Fraxinus angustifolia and the dried shoots of Mentha suaveolens are used by the population of the Tras-os-Montes, which is a region located in the northeast of Portugal. to prepare hot water extracts due to their therapeutic properties. Recently, the contribution of potysaccharides for the therapeutic properties often attributed to various plants hot water extracts has been highlighted. This work will provide a structural characterization of the polysaccharides present in these hot water extracts and will also evaluate their possible macrophage immunostimutatory activity, which might contribute for the therapeutic properties reported for these hot water extracts.
- Immunostimulatory polysaccharides from the hot water extracts of prickled broom (P. tridentatum (L.) Willk) dried inflorescencesPublication . Martins, Vitor Manuel Ramalheira; Simões, Joana; Ferreira, Isabel; Cruz, Maria T.; Domingues, Maria R.M.; Coimbra, Manuel A.The decoctions of prickled broom (Pterospartum trídentatum (L.) Willk.) dried inflorescences have claimed beneficial properties for various health disorders [1, 2]. These can be assigned to several constituents, among them, the polysacharides. In order to unveil the contribution of the polysacharides and their structural features to the modulation of the innate immune activity, the hot water extracts from P. tridentatum dried inflorescences were prepared and fractionated by ethanol precipitation and anion exchange chromatography. A fraction that mainly contained pectic polysaccharides and acetylated galactomannans was isolated. This fraction evidenced in vitro immunostimulatory activity without compromising cellular viability, as evidenced by the increase registered in the nitric oxide (NO) production by macrophages. This activity decreased 60-75% after saponification, confirming that acetylation is an important structural feature for this biological property. In addition, the treatment of pectic polysaccharides with endo-polygalacturonase showed that type-1 and type-11 arabinogalactans, as well as low molecular weight galacturonans and xyloglucans, may also contribute to macrophage NO production. Thus, the polysaccharides present in the dried inflorescences of P. trídentatum may contribute to the health beneficial properties frequently attributed to the decoctions of this plant.
- Using mass spectrometry techniques for the elucidation of structural features of immunostimulatory polysaccharides from medicinal plantsaqueous extractsPublication . Martins, Vitor Manuel Ramalheira; Simões, Joana; Ferreira, Isabel; Cruz, Maria T.; Domingues, Maria R.M.; Coimbra, Manuel A.Polysaccharides are well known for their immunostimulatory properties, which are closely related to structural fèatures, such as molecular weight, branching, acetylation degree and acetylation pattem, and presence of speciflc structures [1, 2]. TTie electrospray ionization-mass spectrometry (ESI-MS) and electrospray ionization tandem mass spectrometry (ESI-MS/MS) have shown to be powerfül techniques that can provide detailed information regarding the structural features of polysaccharides and help to clarify its relation to some ofthe observed immunostimulatory properties [3-6]. TTie present work desenhes the use of ESI-MS and ESI-MS/MS in the confimation and elucidation of structural features of immunostimulatory polysaccharides present in lhe aqueous extracts of Fraxinus angustifolia dned leaws and Ptemapaitum tridentatum dried inflorescences. The polysaccharides present in the aqueous extracts of F. angustifolia dried leaves and P. fridentafum dried inflorescences were isolated and fractionated using dialysis, ethanol precipitation, and anionexchange chromatography. Sugar and linkage analysis suggested that the aqueous extracts of F. angustifolia were mostly composed of pectic polysaccharides, while those from P. tridentatum contained a mixture of pectic polysacchahdes, galactomannans, and also xyloglucans. Selected fractions isolated from lhe aqueous extracts of F. angustifolia and P. tridentatum evidenced an in vitro macrophage immunostimulatory activity, expressed through the production of nitric oxide (NO). Enzymatic hydrolysis of the isolated polysaccharides, fbllowed by size exclusion chromatography of the resulting oligosaccharides (OS), and ESI-MS and ESI-MS/MS characterization allowed to confirm the presence of pectic polysaccharides, possibly with xylogalaturonan domains, in the aqueous extracts of F. angustifolia. For the aqueous extracts of P. fridentatum it was possible to detect the presence of galactomannans acetylated at 0-2. Moreover, it was possible to identify acetylated OS that presented an acetylation pattem with much more acetyl groups than those observed for galactomannans from coffee infusions [3]. The saponification ofthe fraction isolated from the aqueous extracts of P. tridentatum dried inflorescences, which contained the acetylated galactomannans, caused a decrease in the NO macrophage production, confirming lhe galactomannans acetylation as an important structural feature for lhe expression of the in vitm macrophage immunostimulatory activity previously registered.
- Stability evaluation of a bee bread and honey mixturePublication . Fortes, Adriana; Tomás, Andreia; Vilas-Boas, Miguel; Rodrigues, Paula; Martins, Vitor Manuel RamalheiraBee bread is a bee product prepared in honeycombs by fermenting bee pollen collected and partially processed by bees. The interest in bee bread is justified by the fact that it is a nutritionally rich food with potential biological activity, often being classified as a functional food. However, due to the difficulty normally associated with its production, beekeepers have not properly valued bee bread.
- Composição e caracterização do mel de urze (Erica app.) portuguêsPublication . Caveiro, Elsa; Falcão, Soraia; Tomás, Andreia; Martins, Vitor Manuel Ramalheira; Vilas-Boas, MiguelO mel de urze (Erica spp.), é um produto apícola que possui alto valor nutricional, antimicrobiano e antioxidante. Este trabalho teve como objetivo a caracterização de 12 amostras de mel de urze (Erica spp.) português proveniente de sete áreas geográficas de Portugal, através da avaliação dos seus parâmetros de qualidade.
- Manual de boas práticas de segurança e saúde no trabalho apícola uma abordagem para uma cultura de segurança no setorPublication . Pires, Sância; Martins, Vitor Manuel Ramalheira; Igrejas, Getúlio; Coelho, João Paulo; Machado, Ana; Pereira, Ana Paula; Nunes, SofiaA qualidade das condições de trabalho é um dos fatores fundamentais para o sucesso de um sistema produtivo e, o mesmo, também se aplica ao setor apícola. Nesse âmbito, a melhoria da produtividade e da competitividade depende, necessariamente, de uma intervenção no sentido da perceção e melhoria das condições de trabalho. Neste contexto, a elaboração de um Manual de Boas Práticas de Segurança e Saúde no trabalho apícola pretende dar continuidade ao incremento e transferência de conhecimentos técnicos aos apicultores e a todos os agentes envolvidos nesta atividade, contribuindo para uma melhor estruturação do setor. Tendo em consideração a reduzida quantidade de literatura que se encontra disponível, incluindo manuais e outros documentos referentes a Boas Práticas de Segurança e Saúde no trabalho apícola, considera-se que a elaboração de um manual, não vinculativo e de caráter orientador, poderá trazer um contributo relevante e pertinente para a atividade.
- Caracterização reológica de amostras de comerciais de mel de urzePublication . Martins, Vitor Manuel Ramalheira; Caveiro, Elsa; Falcão, Soraia; Vilas-Boas, MiguelO mel de urze (Erica sp. ) português é um produto apícola característico das regiões montanhosas, cuja composição química tem sido objeto de diversos estudos [1, 2]. Este mel é bastante apreciado pelo consumidor devido a algumas das suas propriedades sensoriais, como por exemplo a textura, que é influenciada pelas características reológicas do mel. Deste modo, este estudo teve como objetivo principal a avaliação das características reológicas de amostras comerciais de mel de urze, contribuindo para uma mais completa caracterização deste produto apícola. Foram adquiridas dez amostras comerciais de mel de urze, submetidas a análise polínica para confirmar a sua origem botânica. Apesar dos méis serem comercializados como mel de urze, os resultados da análise polínica sugerem que pelo menos duas das amostras analisadas não correspondem a méis monoflorais de urze, mas sim a amostras de méis monoflorais de castanheiro. A caracterização reológica das amostras de mel foi realizada através do estudo do comportamento de fluxo, utilizando um viscosímetro rotacional (Myr V1-L, equipado com um spindle L4), e da avaliação da textura, através de um ensaio de extrusão de retorno realizado num texturómetro (Stable Micro Systems TA-XT Plus, equipado com uma sonda acoplada a um disco de compressão com 40 mm de diâmetro). O comportamento de fluxo das amostras de mel foi estudado às temperaturas de 25°C, 35°C e 45°C, verificando-se que a viscosidade das amostras de mel diminuiu à medida que aumenta a temperatura do ensaio, tal como descrito em vários estudos [3, 4]. Verificou-se ainda que, de uma forma geral, para as temperaturas de 35°C e 45°C, as amostras de mel apresentaram um comportamento Newtoniano. Para a temperatura de 25°C, as amostras exibiram um comportamento típico de fluído pseudoplástico, sendo ainda possível observar alguma tixotropia. Relativamente aos ensaios de extrusão de retorno, foi possível registar valores de firmeza, consistência, coesividade e índice de viscosidade compreendidos entre 41, 31-189,97 (g), 683, 28-3376,89 (unidades arbitrárias), 22, 46-161,33 (g) e 215,62-1819,16 (unidades arbitrárias), respetivamente. A realização deste trabalho evidenciou a necessidade de encontrar metodologias alternativas/complementares que possibilitem uma mais efetiva garantia da autenticidade dos produtos apícolas, particularmente dos méis monoflorais. Para além disso, as técnicas utilizadas para a caracterização reológica das amostras de mel mostraram ser bastante expeditas, fornecendo resultados que poderão complementar a informação obtida através das habituais análises de rotina realizadas ao mel (cor, pH, acidez livre, condutividade, cinzas, hidroximetilfurfural, prolina, etc... ).
- Nutritional value and antioxidant activity of bee pollen submitted to different preservation techniquesPublication . Lema, Filipe; Tomás, Andreia; Vilas-Boas, Miguel; Martins, Vitor Manuel RamalheiraThe moisture content in bee pollen is one parameter of greatest interest for the preservation and quality of this product, since bee pollen is subject to the proliferation of microbiological contaminations that can make its consumption and commercialization unfeasible [1]. Various studies have stated that the choice of preservation technique can have an impact on the chemical composition and antioxidant activity of pollen [2,3,4,5]. Thus, this work intends to evaluate the immediate impact, and also over a storage period of 9 months, of the application of several preservation techniques in the chemical composition and antioxidant activity of the pollen. The bee pollen was collected in Bragança region and frozen at -18ºC, being subsequently preserved through lyophilization or drying in an oven at 35ºC, 40ºC or 45ºC. The chemical composition (moisture content, ash, fat, protein, fructose, glucose and total phenolic compounds) and antioxidant activity (DPPH and reducing power) were analysed immediately after the application of the preservation technique and after 1, 3, 6, and 9 months of storage. In addition to the expected reduction in moisture content, other chemical parameters were significantly affected during the storage period. In general, considering the maintenance of the nutritional value of the pollen, lyophilization was shown to be the most appropriate preservation technique. However, the use of lyophilization appears to have a more evident negative impact on the content of total phenolic compounds and on the antioxidant activity of the pollen, when compared with the oven drying technique, performed at a temperature of 45°C.
- Pectic polysaccharides from the infusions of P. tridentatum, F. angustifolia and M. suaveolens: structural characterization and inflammatory influence evaluationPublication . Martins, Vitor Manuel Ramalheira; Francisco, Vera; Cruz, Maria T.; Batista, Maria T.; Coimbra, Manuel A.In Tras-os-Montes region (Portugal), the small shrub (Pterospartum tridentatum) , the narrow-leafed ash (Fraxinus angustifolia), and the apple mint (Mentha suaveolens) are vegetable species frequently used in the preparation of infusions for medicinal purposes. According to the popular tradition, the infusions prepared from P. tridentatum, F. angustifolia and M. suaveolens protect against diabetes, hypertension, high levels of cholesterol and uric acid.