Percorrer por autor "Prieto Lage, Miguel A."
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- Adansonia digitata L. (mukua): um possível alimento funcionalPublication . Fernandes, Filipa Alexandra; Carocho, Márcio; Calhelha, Ricardo C.; Pires, Tânia C.S.; Freitas, José Carlos; Prieto Lage, Miguel A.; Heleno, Sandrina A.; Barros, LillianAdansonia digitata L. é espécie africana com vários usos tradicionais, nomeadamente medicinal e alimentar [1,2]. A polpa do seu fruto, comumente conhecido como mukua, está aprovada como um ingrediente alimentar pela Comissão Europeia e pela “Food and Drug Administration of the United States of America” [1]. Assim o objetivo deste trabalho foi comprovar a potencialidade da polpa da mukua como um alimento funcional através da sua caracterização nutricional, mineral e bioativa. O perfil nutricional foi obtido aplicando metodologias oficiais de análise AOAC [3]. O conteúdo mineral foi determinado por espectrofotometria de absorção atómica e o potencial bioativo foi determinado através da atividade antioxidante pelo ensaio antioxidante celular (CAA) e um ensaio de inibição de substâncias reativas do ácido tiobarbitúrico (TBARS). Além disso, a atividade antimicrobiana foi também determinada, através do método de microdiluição, e a atividade antitumoral foi avaliada em três linhas celulares tumorais humanas: adenocarcinoma gástrico (AGS), carcinoma de mama (MCF-7), células de carcinoma de pulmão (NCI-H460), e a citotoxicidade em culturas de células não tumorais de rim de macaco africano (VERO), através do ensaio da Sulforrodamina B. Relativamente aos resultados obtidos, a polpa de mukua apresentou um teor de humidade muito baixo (11,9 + 0,3 g/100 g ms). Os macronutrientes presentes em maior quantidade foram os hidratos de carbono (89,6 ± 0,2 g/100 g ms), seguidos das proteínas (2,7 ± 0,3 g/100 g ms) e da gordura bruta (1,8 + 0,1 g/100 g ms), representando um valor energético de 386 ± 1 kcal/100 g ms. Quanto ao perfil mineral, a amostra revelou um alto teor em potássio (20,4 ± 0,8 g/100 g ms), estando também presentes minerais como o magnésio (3,28 ± 0,08 g/100 g ms), o cálcio (2,79 ± 0,07 g/100 g ms), o manganês (2,02 ± 0,09 g/100 g ms) e o ferro (1,53 ± 0,09 g/100 g ms). Em relação à atividade antioxidante, a polpa inibiu cerca de 32% da oxidação celular no método CAA e exibiu um valor de EC50 de 23,0 ± 0,1 μg/mL no ensaio de TBARS. Para a atividade antimicrobiana, a polpa apresentou atividade bacteriostática contra a maioria das bactérias testadas. No ensaio de citotoxicidade, a polpa demonstra capacidade de inibir a proliferação celular contra as linhas tumorais testadas, principalmente contra AGS com valores de GI50 de 92 ± 1 μg/mL, sem toxicidade para as células não-tumorais. Este estudo mostra que a polpa de mukua, além de ser nutricionalmente interessante, possui alto teor em minerais, nomeadamente em potássio que é um composto essencial para a bom funcionamento do corpo, estando associado à prevenção de doenças como diabetes, osteoporose e ainda doenças cardiovasculares. Além disso, a polpa da mukua possui alto potencial bioativo, o que indica que o seu consumo pode oferecer benefícios para a saúde, tornando-o num potencial alimento funcional.
- Agrocybe cylindracea bio-residues: a sustainable source of ergosterol-rich bioactive extractsPublication . Silva, Ana Rita; Pinela, José; Caleja, Cristina; Costa, Cristina; Barros, Joana; Ferreira, Inês; Nunes, João; Prieto Lage, Miguel A.; Barros, Lillian; Ferreira, Isabel C.F.R.The world production of edible mushrooms has increased more than 30‐fold since 1978 and, on average, each customer consumes 5 kg of mushrooms per year [1]. Depending on the dimension of the mushroom industry, the amount of obtained by-products may range from 20 to 35% in weight of fresh mushroom [2]. Indeed, 38% of the 90 million tonnes of food waste produced by the European Union every year has its origin in the food manufacturing sector [3]. However, there are several strategies of transforming these wastes into high value-added products based on the cascade use principle, and this is exactly what the MicoBioExtract project aims to perform. Thus, the bio-residues of a popular edible mushroom in southern Europe, Agrocybe cylindracea, were studied as a sustainable source of bioactive extracts [4]. Ergosterol has been reported to be one of the most important compounds, contributing to the health-promoting benefits, associated with mushrooms’ consumption [2]. Its extraction was performed using a heat-assisted technique and applying the response surface methodology, in order to optimize the combined effects of the variables time, temperature and solvent percentage, using a circumscribed central composite design with 16 independent combinations and 4 replicated centre points. At the optimum condition predicted by the model, the bioactivity of the extract was tested, evaluating the antioxidant (TBARS assay) and cytotoxic (in a porcine liver primary cell culture, PLP2) activities. The results obtained from the optimization study showed a significant interaction between temperature and extraction time, with an 8.24% extraction yield. The global optimum condition for ergosterol extraction predicted by the model was 150 min at 90 °C, with 329 mg of ergosterol per 100 g of dry weight sample. Regarding the bioactive potential, namely the antioxidant activity, this extract was capable of preventing the formation of malondialdehyde, a secondary product of lipid peroxidation in the TBARS assay. Concerning the cytotoxicity of the extracts against the PLP2 cell line, the results showed no significant cytotoxic effect, with GI50 values higher than 400 μg/mL. Thus, the extraction of molecules with a high nutritional and bioactive value from mushroom bio-residues and the goal to incorporate them in functional foods and nutraceuticals could boost the circular bio-economy, and help developing strategies towards promoting sustainability.
- Agrocybe cylindracea bio-residues: a sustainable source of ergosterol-rich bioactive extractsPublication . Silva, Ana Rita; Pinela, José; Caleja, Cristina; Costa, Cristina; Barros, Joana; Ferreira, Inês; Nunes, João; Prieto Lage, Miguel A.; Barros, Lillian; Ferreira, Isabel C.F.R.The world production of edible mushrooms has increased more than 30‐fold since 1978 and, on average, each customer consumes 5 kg of mushrooms per year [1]. Depending on the dimension of the mushroom industry, the amount of obtained by-products may range from 20 to 35% in weight of fresh mushroom [2]. Indeed, 38% of the 90 million tonnes of food waste produced by the European Union every year has its origin in the food manufacturing sector [3]. However, there are several strategies of transforming these wastes into high value-added products based on the cascade use principle, and this is exactly what the MicoBioExtract project aims to perform. Thus, the bio-residues of a popular edible mushroom in southern Europe, Agrocybe cylindracea, were studied as a sustainable source of bioactive extracts [4]. Ergosterol has been reported to be one of the most important compounds, contributing to the health-promoting benefits, associated with mushrooms’ consumption [2]. Its extraction was performed using a heat-assisted technique and applying the response surface methodology, in order to optimize the combined effects of the variables time, temperature and solvent percentage, using a circumscribed central composite design with 16 independent combinations and 4 replicated centre points. At the optimum condition predicted by the model, the bioactivity of the extract was tested, evaluating the antioxidant (TBARS assay) and cytotoxic (in a porcine liver primary cell culture, PLP2) activities. The results obtained from the optimization study showed a significant interaction between temperature and extraction time, with an 8.24% extraction yield. The global optimum condition for ergosterol extraction predicted by the model was 150 min at 90 °C, with 329 mg of ergosterol per 100 g of dry weight sample. Regarding the bioactive potential, namely the antioxidant activity, this extract was capable of preventing the formation of malondialdehyde, a secondary product of lipid peroxidation in the TBARS assay. Concerning the cytotoxicity of the extracts against the PLP2 cell line, the results showed no significant cytotoxic effect, with GI50 values higher than 400 μg/mL. Thus, the extraction of molecules with a high nutritional and bioactive value from mushroom bio-residues and the goal to incorporate them in functional foods and nutraceuticals could boost the circular bio-economy, and help developing strategies towards promoting sustainability.
- Algae as a source of bioactive compounds to prevent the development of type 2 diabetes mellitusPublication . Popović-Djordjević, Jelena; Katanić Stanković, Jelena S.; Mihailović, Vladimir; González Pereira, Antía; García-Oliveira, Paula; Prieto Lage, Miguel A.; Simal-Gandara, JesusType 2 diabetes mellitus is a complicated metabolic disorder characterized by hyperglycemia and glucose intolerance. It is considered a new pandemic and its control involves numerous challenges. Although many of the measures are based on improving life habits, diet is also of vital importance due to bioactive compounds present in food. In this regard, several raw materials have been investigated whose bioactivities seem to slow the progression of this disease. Within these matrices, there are algae of importance, such as brown algae, showing to have beneficial effects on glycemic control. These pieces of evidence are increasing every day due to the development of cell or animal models, which lead to the conclusion that bioactive compounds may have direct effects on decreasing hyperglycemia, enhancing insulin secretion and preventing the formation of amyloid plaques.
- Algal nutraceuticals: a perspective on metabolic diversity, current food applications, and prospects in the field of metabolomicsPublication . Garcia-Perez, Pascual; Cassani, Lucia; Garcia-Oliveira, Paula; Xiao, Jianbo; Simal-Gandara, Jesus; Prieto Lage, Miguel A.; Lucini, LuigiThe current consumers’ demand for food naturalness is urging the search for new functional foods of natural origin with enhanced health-promoting properties. In this sense, algae constitute an underexplored biological source of nutraceuticals that can be used to fortify food products. Both marine macroalgae (or seaweeds) and microalgae exhibit a myriad of chemical constituents with associated features as a result of their primary and secondary metabolism. Thus, primary metabolites, especially polysaccharides and phycobiliproteins, present interesting properties to improve the rheological and nutritional properties of food matrices, whereas secondary metabolites, such as polyphenols and xanthophylls, may provide interesting bioactivities, including antioxidant or cytotoxic effects. Due to the interest in algae as a source of nutraceuticals by the food and related industries, novel strategies should be undertaken to add value to their derived functional components. As a result, metabolomics is considered a high throughput technology to get insight into the full metabolic profile of biological samples, and it opens a wide perspective in the study of algae metabolism, whose knowledge is still little explored. This review focuses on algae metabolism and its applications in the food industry, paying attention to the promising metabolomic approaches to be developed aiming at the functional characterization of these organisms.
- Análise do perfil nutricional de partes comestíveis da Portulaca oleracea L. produzida pela técnica de rotação de culturasPublication . Paschoalinotto, B.H.; Prieto Lage, Miguel A.; Polyzos, Nikolaos; Compocholi, Maria; Petropoulos, Spyridon Α.; Ferreira, Isabel C.F.R.; Dias, Maria Inês; Barros, LillianPortu/aca o/eracea L. (beldroega) é uma planta silvestre comestível com reconhecidas propriedades medicinais. As suas folhas e caules são popularmente consumidos preparadas como sumos, mas também em cru ou cozidas em saladas. Recentemente a beldroega foi descrita como alimento funcional, devido ao seu alto valor nutricional, o que fez despertar um grande interesse na sua produção em cultivo controlado, especialmente quando se considera a sua grande adaptabilidade como espécie a várias condições adversaslul. Considerando a importância de explorar novas fontes sustentáveis de nutrientes e compostos bioativos alinhado com a manutenção da qualidade do solo, a aplicação da técnica agrícola de rotação de culturas tem vários benefícios agronómicos, que estão já bem documentadosl3l. Com vista a obter beldroegas com maior valor nutricional e terapêutico, foi aplicada este tipo de técnica na sua produção em três pontos experimentais com rotação com uma cultura de feijão. O conteúdo em proteína bruta, lípidos totais, fibras dietéticas totais, cinzas e hidratos de carbono (por diferença) das folhas e caules foram avaliados por métodos AOAC. A energia foi calculada de acordo com a equação: energia (kcal por 100 g) = 9 x (g gordura) + 4 x (g proteína + g hidratos de carbono) + 2 x (g fibras dietéticas totais). Nos lípidos totais e proteína bruta foram observadas diferenças nutricionais significativas entre as parcelas experimentais, bem como nas folhas e caules da beldroega, sendo que as folhas revelaram as maiores quantidades. O teor de cinzas não variou entre folhas e caules da mesma parcela experimental, mas foi novamente nas folhas que se observou um maior conteúdo em fibras dietéticas totais e maior valor energético. A produção de beldroega em solo continua a ser bastante promissora, no entanto, a produção com rotação com uma cultura de feijão revelou maiores teores de fibra brutal4l. Com os resultados preliminares obtidos, o uso de técnicas de rotação de culturas permite a obtenção de beldroegas com alto valor nutricional, para além de aumentar a sua disponibilidade na indústria e, por conseguinte, para o consumidor final.
- Analysis of the oxypropylation process of a lignocellulosic material, almond shell, using the response surface methodology (RSM)Publication . Pinto, João A.; Prieto Lage, Miguel A.; Ferreira, Isabel C.F.R.; Belgacem, Mohamed Naceur; Rodrigues, Alírio; Barreiro, M.F.
- Analytical metabolomics and applications in health, environmental and food sciencePublication . Fraga-Corral, Maria; Carpena Rodríguez, María; Garcia-Oliveira, Paula; Pereira, Antia Gonzalez; Prieto Lage, Miguel A.; Simal-Gandara, JesusMetabolomics is a young field of knowledge that arises linked to other omics such as genomics, transcriptomics, and proteomics. This discipline seeks to understand the performance of metabolites, identifying, quantifying them, and thus understanding its mechanism of action. This new branch of omics science shows high potential, due to its noninvasive character and its close relation with phenotype. Several techniques have been developed to study the metabolome of biological samples, fundamentally nuclear magnetic resonance (NMR), mass spectrometry (MS) and vibrational spectrometry (VS) or a combination of several techniques. These techniques are focused to separate, detect, characterize, and quantify metabolites, as well as elucidate their structures and their function on the metabolic pathways they are involved. However, due to the complexity of the metabolome, in most cases it is necessary to apply several of these techniques to understand completely the whole scenery. This review is aimed to offer a summary of the current knowledge of these analytical techniques for metabolomics and their application to different fields as environmental, food or health sciences. Each technique shows different advantages and drawbacks depending on their technical characteristics and limitations, some factors, such as the aim of the study or the nature of the biological sample will condition the choice. Regarding their applications, NMR has been employed specially to identify new compounds and elucidate structures. The use of MS has gained popularity because of its versatility, easiness to be coupled to separation techniques and its high sensitivity. Whereas VS is widely employed for in situ studies, due to its nondestructive character. Metabolomics applications in different science fields are growing each year, due to advances in analytical techniques and combination with other omics that allow to increase the comprehension of metabolic processes. Further development of analytical tools is necessary to continue exploiting all the possibilities of metabolomics.
- Anthocyanin-rich extract obtained from Prunus Spinosa L. by ultrasound assisted extraction for coloring purposesPublication . Leichtweis, Maria Gabriela; Pereira, Carla; Prieto Lage, Miguel A.; Alves, Maria José; Calhelha, Ricardo C.; Barreiro, M.F.; Baraldi, Ilton J.; Ferreira, Isabel C.F.R.; Barros, LillianAnthocyanins are a group of natural pigments presenting a range of colours between red, blue, and violet that are characteristic of various fruits and vegetables. A complex profile of anthocyanins, predominantly cyanidin 3-rutinoside and peonidin 3-rutinoside, was previously identified in Prunus spinosa L. fruit, a bitter and astringent fruit from a wild shrub that is poorly commercially exploited [1]. In this sense, the objective of this work was to develop a natural food colourant based on anthocyanins extracted from the epicarp of P. spinosa fruits. For that purpose, a conventional extraction method, maceration, and a rapid and low-cost ultrasound procedure were applied for the extraction of anthocyanins from this matrix. To achieve the conditions that maximize anthocyanins’ extraction, a response surface methodology was applied using a circumscribed central composite design with three variables and five levels, being the variables time, temperature, and ethanol content, in the case of maceration extraction, whereas for ultrasound assisted extraction, temperature was replaced by ultrasound power. The anthocyanins were identified and quantified by HPLC-DAD-ESI/MS. The optimized extract was assessed in terms of antioxidant and antimicrobial capacity, and hepatotoxicity. Ultrasound assisted extraction was the most efficient method, under optimum conditions of 5.00±0.15 min, 400.00±32.00 W and 47.98±2.88% ethanol, where the extraction yield was 68.60±2.06% (v/v), with a total anthocyanin content of 18.17±1.82 mg/g of dry extract and 11.76±0.82 mg/g of dry epicarp. Regarding bioactivity, the optimized extract showed antioxidant and antimicrobial activity and it did not show hepatotoxic effects in a primary culture of porcine liver cells. To validate its coloring properties, the anthocyanin-rich extract was incorporated into a typical Brazilian confectionery product "beijinho", proving its applicability as food colorant.
- Antimicrobial and antifungal activities of a coloring extract rich in betacyanins obtained from the flowers of Gomphrena globosa LPublication . Roriz, Custódio Lobo; Barros, Lillian; Prieto Lage, Miguel A.; Morales, Patricia; Soković, Marina; Barreiro, M.F.; Ferreira, Isabel C.F.R.There is a huge diversity of pigments from natural origin that can be exploited as colorants in the food industry. Nonetheless, they can additionally provide several bioactive properties, which represent an added-value for food products. Carotenoids, chlorophylls, anthocyanins and betalains are some of the most studied plant-based pigments. Betalains, can be subdivided according to their chemical structure into betacyanins and betaxanthins [1]. Although less exploited than Beta vulgaris L., Gomphrena globosa L. is an important source of betacyanins [2], with antimicrobial and antifungal activity [3]. Thus, the aim of this study was to obtain a pigmented extract from G. globosa with a high antimicrobial and antifungal activity. This objective was implemented by the application of the response surface methodology (RSM), a robust optimization technique that allows to study jointly the effects of several variables and responses, namely in extraction procedures (in this case ultrasound assisted extraction (UAE)). To evaluate the antimicrobial and antifungal properties, the responses were the minimum inhibitory (MIC), minimum bactericidal (MBC) and minimum fungicidal (MFC) concentrations. The optimized UAE conditions were: 10.8 min, 410.5 W, 57.8% ethanol content (ethanol-water mixtures were used) and 5 g/L as solid-liquid ratio, providing the following responses: 1) antibacterial activity: MIC of ~0.15-0.35 g/L) and MBC of ~0.30-0.65 g/L; and 2) antifungal activity: MIC of ~0.20-0.30 g/L and MFC of ~0.40-0.65 g/L. In conclusion, the obtained results evidenced the potential application of the extracts from G. globosa as sources of betacyanins (natural colorants), but also as important antimicrobial and antifungal agents.