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- Natural sporopollenin microcarriers: Morphological insights into their functional performance for drug encapsulation and releasePublication . Aylanc, Volkan; Peixoto, Andreia F.; Akyuz, Lalehan; Vale, Nuno; Freire, Cristina; Vilas-Boas, MiguelNatural sporopollenin microcapsules (SMCs) derived from pollen offer versatility and efficiency for different applications, from environmental remediation to food and therapeutics delivery. A critical gap remains in understanding the relationship between SMCs morphologies and their effectiveness in drug loading and delivery. Herein, we encapsulated 5-Fluorouracil (5-FU), a model anticancer drug, into SMCs derived from seven bee monofloral pollens, each exhibiting distinct morphological features, and examined how their loading and release performance correlated with their morphology. Microscopic and particle size analyses revealed that the chemically purified SMCs were hollow, with sizes ranging from 11.0 to 35.6 μm, without significant size changes after drug loading. Encapsulation efficiency achieved through vacuum-assisted loading (18–28 %) generally surpassed that of passive and compression loading techniques. Moreover, there was a trend of increasing encapsulation efficiency with larger SMC sizes, albeit with some exceptions. In a sequential release environment simulating the in vitro gastrointestinal tract and colonic fermentation, smaller SMCs exhibited a faster release profile, whereas larger ones demonstrated a slower sustained release. The quantity and shape of apertures on SMCs walls significantly impacted their drug-loading capacity and release characteristics. Additionally, natural SMCs remained structurally intact even in the presence of digestive enzymes, varying pH levels, and colonic bacteria, indicating minimal degradation under these conditions. Overall, the findings highlight the significant influence of SMCs morphologies on their functional performance and provide a list of SMCs-based microstructures to guide drug release applications.
- 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 Characterization of Microcapsules from Common Bee Pollen for the Development of Delivery SystemsPublication . Ertosun, Seymanur; Aylanc, Volkan; Peixoto, Andreia F.; Santamaria-Echart, Arantzazu; Russo-Almeida, Paulo; Freire, Cristina; Vilas-Boas, MiguelExine, in the form of a natural microcapsule, refers to the outermost layer of the pollen grains and is composed of a complex mixture of sporopollenin, a highly resistant polymer, which makes it durable and able to withstand harsh conditions. Distinctive features of sporopollenin have attracted interest in the encapsulation of bioactive substances. Herein, we describe the pathway to producing sporopollenin microcapsules (SMCs) by exploiting bees and trapping common bee pollen pellets, offering a simple approach to acquiring substantial amounts of pollen grains for industrial application. Palynological results showed that separating bee pollen pellets by colour could lead to almost pure products ranging from 90 to 96%, depending on the pollen species. Subsequently, a single extraction technique removed around 82– 86% of the proteinaceous content, which could cause potential allergic reactions in humans. Detailed morphological analysis by scanning electron microscope (SEM), confocal laser scanning microscopy (CLSM), atomic force microscopy (AFM), and laser diffraction particle size (LDPS) analysis proved that the purified SMCs retained their 3D micro-structures, besides being hollow and uniform micron-scale size. Fourier-transform infrared spectroscopy (FTIR) findings point out that the sporopollenin biopolymer structure of the pollen grain comprises distinct aliphatic and aromatic domains, and the purification of the SMCs resulted in the loss of nitrogen-related peaks. The hydrophobic/hydrophilic properties of the SMCs, evaluated by contact angle measurements, showed variability between pollen, depending on the specificities of their chemical structure. Simultaneous thermal analysis (STA) confirmed SMCs thermal stability up to 451 °C. Altogether, we showed that green microcapsules with various morphological properties could be produced by simply processing Castanea spp., Cistus spp., Erica spp., Olea spp, and Rubus spp, all common bee pollen pellets available in large quantities in the northeast of Portugal, but also many other countries. These microcarriers promise applicability to various fields, from pharmaceuticals to the food industry.
- Tratamentos alternativos no combate à Varroa: aplicação na apicultura biológica em Trás-os-Montes e Alto DouroPublication . Vilas-Boas, MiguelA varroose é uma doença parasitária externa das abelhas causada por um ácaro denominado por Varrôa destructor. Este parasita originalmente presente nas abelhas melíferas asiáticas Apis cerana, onde coexiste numa relação simbiótica parasita/hospedeiro, foi detectado pela primeira vez em 1963 em colónias de abelhas Appis mellifera.
- Eficácia da própolis no controlo da loque americana. Avaliação em zonas controladasPublication . Vilas-Boas, Miguel; Veloso, Ana C.A.; Peres, António M.; Dias, L.G.; Dias, Teresa; Cardoso, Susana M.; Kluskens, Leon; Rocha, Isabel
- Production of chitosan-based biodegradable active films using bio-waste enriched with polyphenol propolis extract envisaging food packaging applicationsPublication . Carli, Cristiane de; Aylanc, Volkan; Mouffok, Kheira; Santamaria-Echart, Arantzazu; Barreiro, M.F.; Tomás, Andreia; Pereira, Celeide; Rodrigues, Paula; Vilas-Boas, Miguel; Falcão, SoraiaDeveloping biodegradable active films has been a promising green approach to overcoming global concerns over the environmental pollution and human health caused by plastic utilization. This study aimed to develop active films based on chitosan (CS), produced from waste crayfish (Procambarus clarkii) shells enriched with bioactive extract (5–20%) of propolis (PS) and to characterize its properties, envisaging food packaging applications. The chromatographic profile of PS extract confirmed its richness, with 41 phenolic compounds. With increasing extract addition to the chitosan, the thickness of the films increased from 61.7 to 71.7 μm, causing a reduction in the light transmission rate, along with a greenish colour shift. The interactions between PS extract and CS was confirmed by infrared spectroscopy, at the same time that the microstructural integrity of the films was checked on the scanning electron microscopy micrographs. The findings also showed that addition of PS enhanced the films thermal stability and mechanical properties e.g., tensile modulus, yield strength, and stress at break. Besides, it improved the antioxidant and antimicrobial activities. Overall, CS-based composite films seem a promising green alternative to petroleum-based synthetic plastics allowing to extend the shelf life of food products due to their eco-friendly nature.
- Evaluation of antioxidant and anticancer activity of mono- and polyfloral moroccan bee pollen by characterizing phenolic and volatile compoundsPublication . Aylanc, Volkan; Larbi, Samar; Calhelha, Ricardo C.; Barros, Lillian; Rezouga, Feriel; Rodriguez-Flores, Maria Shantal; Seijo-Coello, M. Carmen; El Ghouizi, Asmae; Lyoussi, Badiâa; Falcão, Soraia; Vilas-Boas, MiguelBee pollen is frequently characterized as a natural source of bioactive components, such as phenolic compounds, which are responsible for its pharmaceutical potential and nutritional properties. In this study, we evaluated the bioactive compound contents of mono- and polyfloral bee pollen samples using spectroscopic and chromatographic methods and established links with their antioxidant and antitumor activity. The findings demonstrated that the botanical origin of bee pollen has a remarkable impact on its phenolic (3-17 mg GAE/g) and flavonoid (0.5-3.2 mg QE/g) contents. Liquid chromatography-mass spectrometry analysis revealed the presence of 35 phenolic and 13 phenylamide compounds in bee pollen, while gas chromatography-mass spectrometry showed its richness in volatiles, such as hydrocarbons, fatty acids, alcohols, ketones, etc. The concentration of bioactive compounds in each sample resulted in a substantial distinction in their antioxidant activity, DPPH (EC50: 0.3-0.7 mg/mL), ABTS (0.8-1.3 mM Trolox/mg), and reducing power (0.03-0.05 mg GAE/g), with the most bioactive pollens being the monofloral samples from Olea europaea and Ononis spinosa. Complementarily, some samples revealed a moderate effect on cervical carcinoma (GI(50): 495 mu g/mL) and breast adenocarcinoma (GI(50): 734 mu g/mL) cell lines. This may be associated with compounds such as quercetin-O-diglucoside and kaempferol-3-O-rhamnoside, which are present in pollens from Olea europaea and Coriandrum, respectively. Overall, the results highlighted the potentiality of bee pollen to serve health-promoting formulations in the future.
- 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.
- Manual de apicultura em modo de produção biológicoPublication . Vilas-Boas, MiguelO presente documento pretende promover a apicultura em modo de produção biológico como mais uma ferramenta ao dispor do apicultor para o desenvolvimento da sua actividade. Assim, descreve-se o enquadramento da apicultura no âmbito da agricultura biológica e de uma forma sucinta apresentam-se os regulamentos, os procedimentos administrativos e algumas das especificidades no maneio apícola em modo de produção biológico. São focados com particularidade alguns aspectos relativos ao controlo da varroa, considerado por vezes e de forma sobrevalorizada, como uma das condicionantes neste modo de produção. Aqui apresentam-se a experiência e os resultados obtidos na execução do projecto “Promoção e estímulo à produção biológica de mel” fruto da colaboração entre a Escola Superior Agrária de Bragança, a Associação de Apicultores do Parque Natural do Douro Internacional e a Associação de Apicultores do Parque Natural de Montesinho e financiado pelo programa Agro medida 8.1 DE&D. Este manual não substitui uma consulta das disposições regulamentares mas apenas pretende ser um complemento informativo. Em nota final, alerta-se o leitor para a nova regulamentação Europeia, Reg. (CE) n.º 834/2007 a aplicar para o ano de 2009 e a demais que em breve virá complementar este novo regulamento.
- Characterization of new phenolic derivatives in Portuguese propolis by electrospray mass spectroscopyPublication . Falcão, Soraia; Vilas-Boas, Miguel; Freire, Cristina; Domingues, Maria R.M.; Cardoso, Susana M.Propolis is a resinous substance collected by honeybees from tree buds, comprising plant exudates, secreted substances from bee metabolism, pollen and waxes. This product is widely used in traditional medicine [I] and it has recently gained popularity as a health food supplement. Currently, it is extensively used in foods and beverages, and it is claimed to improve health and prevent diseases such as inflammation, heart disease, diabetes and cancer.