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- Investigação Aplicada - Fichas de trabalho: Conceção de projeto de InvestigaçãoPublication . Ribeiro, Jaime; Ribeiro, Vânia SantosO processo de investigação é pautado pela exigência inerente ao mesmo, preenchido com dúvidas, incertezas e inseguranças, havendo sempre novos desafios e assuntos (problemas) a explorar e a investigar. Para alguém que enceta o seu percurso é um desafio acrescido, associado ao problema de investigação que se almeja responder, há o problema de aprender a fazer investigação. A presente ficha pretende ajudar a estruturar um projeto de investigação através da resposta a questões concretas. Após a resposta às questões, acredita-se que será possível facilmente transpor para o documento formal o projeto que se pretende realizar. Alerta-se que em qualquer fase do processo de investigação, incluindo a conceção do projeto, com vista à tomada de decisão e respetiva fundamentação, é essencial que se faça um exercício de resposta às seguintes questões: O quê? (o que se pretende fazer) Porquê? (qual o propósito no âmbito da investigação) Como? (qual o processo, qual o instrumento, qual a técnica, com quem) Se não se obtiver uma resposta objetiva a estas questões ainda existem reflexões a fazer, decisões a realizar e planeamento a executar. Os aspetos mais pertinentes a considerar no processo de investigação são os seguintes: Selecionar uma questão ou área problemática para pesquisar; Formular uma hipótese; Selecionar um método, planeamento e recolha de dados; Analisar os dados obtidos; Realizar um resumo das observações e retirar conclusões da interpretação dos resultados; Escrever um relatório do projeto e comunicar os resultados. Numa última nota é importante salientar que todo processo de investigação deve dirigir-se para a redação de uma publicação, pelo que se deve procurar obter todos os elementos, tais como: Introdução (contextualização e justificação para a investigação) Objetivos (objetivo geral e/ou específicos) Métodos (como se recolheram e analisaram os dados para se produzir resultados) Resultados (o que se obteve a partir dos dados, o que se descobriu) Conclusões (da análise dos resultados quais as considerações que emergem) Este documento contém duas fichas de trabalho que devem ser preferencialmente trabalhas em sala de aula e/ou com apoio do orientador do projeto. A primeira ficha reporta-se identificação do problema e investigar e, na continuidade, a segundo à delineação do desenho de investigação. Estas fichas devem ser preenchidas com desfasamento temporal. A primeira ficha em aulas iniciais e a segunda após uma introdução às metodologias de investigação.
- Low-Protein Diets, Malnutrition, and Bone Metabolism in Chronic Kidney DiseasePublication . Cidália, Almeida D.; Guimarães, Carla; Ribeiro, Vânia S.; Vaz, Daniela C.; Martins, Maria JoãoChronic kidney disease (CKD) has a high prevalence worldwide, with increasing incidence in low- and middle-income countries, and is associated with high morbidity and mortality, particularly from cardiovascular disease. Protein-restricted diets are one of the most widely used non-pharmacological approaches to slow the progression of CKD and prevent associated metabolic abnormalities. However, some concerns have been raised about the long-term safety of these diets, particularly with regard to patients’ nutritional status and bone and mineral disorders. Therefore, the aim of this article is to review the most recent scientific evidence on the relevance of using protein-restricted diets (with or without keto-analogue supplementation) and, in particular, their relationships with malnutrition and mineral and bone disorders in people with CKD without kidney replacement therapies. Although protein-restricted diets, especially when supplemented with keto-analogues and highly personalized and monitored, do not appear to be associated with malnutrition, research on their effects on bone and mineral disorders is scarce, deserving further investigation.
- Nutritional profile of the Portuguese cabbage (Brassica oleracea L var. costata) and its relationship with the elemental soil analysisPublication . Pessoa, Maria; Campos, Paula; Pais, Isabel; Feteiro, Ana; Canuto, Daniela; Simes, Manuela; Pelica, João; Pataco, Inês; Ribeiro, Vânia; Reboredo, Fernando; Ramalho, Jos; Lidon, FernandoThe economic and financial crisis has increased the number of urban horticulture on lands close to present or past industrial areas. “Tronchuda” or the Portuguese cabbage (Brassica oleraceae L var. costata DC) was studied because of its importance in Portuguese diet. It belongs to a number of economically significant horticultural crops (Brassica species), which are also known to be nutritionally well-balanced vegetables. “Tronchuda” produced in urban horticultures from 4 regions of mainland Portugal was studied for its nutritional profile along with elemental soil analysis of each sampling site. This study revealed significant interactions between essential elements in soil and plant leaves - the edible part of the plant for human nutrition. In general, these organs contained poor concentrations of Fe and Si, while Mn is absent, regardless of the sampling sites. Conversely, Ca levels were abundant with values ranging between 3.3% and 3.9%. Soils from CAP showed a soil nutrient exhaustion of Fe, Mn and Mo, although the highest protein and sucrose contents in the leaves was observed in plants growing in those soils. Protein, lipids and carbohydrates concentrations differed according to sampling site, reflecting different production practices.
- Retention of minerals, antioxidants, pigments, and glucosinolates by broccoli florets and green bean pods boiled in alkaline, neutral and acidic watersPublication . Ribeiro, Vânia S.; Cruz, Pedro F.; Almeida, Zaida L.; Silva, Cândida G.; Silva, Maria Isabel; Silva, Inês S.; Santos, Liliana R.; Santos, Marta T.; Guimarães, Carla; Brito, Rui M.M.; Guerra, Mauro; Reboredo, Fernando; Pereira, Cidália D.; Vaz, Daniela C.Given the poor palatability and chewability of crude green bean pods (Phaseolus vulgaris) and broccoli florets (Brassica oleracea var. italica Plenck) these vegetables are generally microwaved, steamed or water boiled. Hence, here, we evaluated the contents of minerals, antioxidants, phenolics, glucosinolates, pigments, colour, texture and flavour of water-boiling broccoli and green bean pods, with four mineral waters with variable composition and pH. Plant matrices were characterized by High Resolution Magic-Angle Spinning (HR-MAS) and plant extracts were analysed by pseudo-2D Diffusion-ordered nuclear magnetic resonance (NMR) spectroscopy. Mineral waters ranging from acidic to neutral and alkaline were used and the colour properties (lightness, greenness/yellowness, colour saturation and hue angles), minerals and bioactive contents retained by the vegetables were compared to microwaved and steamed material. Boiling bean pods for 5 min extracted more polyphenols and antioxidants, particularly with more acidic waters, than 5 min of microwaving or steaming. However, even if boiling broccoli with more acidic water could better preserve glucosinolates, the food material presented lower retention of pigments and poor palatability. Cooking with more alkaline water increased mineral retention and broccoli greenness, also leading to highest scores in “colour”, “texture”, and “flavour”. Hence, samples cooked in more alkaline water presented higher acceptability.
- Livro de Atas - 4.ª Conferência Campus Sustentável (CCS2022)Publication . Bernardo, Hermano; Morais, Joana; Ramos, João; Sousa, João; Santos, Joaquim; Gonçalves, Luísa; Neves, Luís; Oliveira, Mário; Matos, Rui; Mendes, Susana; Ribeiro, Vânia; Santos Ribeiro, VâniaA sustentabilidade, nas suas variadas vertentes designadamente ambiental, económica e social, tem estado, desde sempre, no topo das prioridades do Instituto Politécnico de Leiria (IPL). Esta postura encontra-se espelhada, nomeadamente, no plano estratégico 2030 da instituição que prevê um conjunto alargado de medidas que fomentam a adoção de práticas sustentáveis nas atividades e quotidiano da comunidade académica. Dada a situação específica do IPL no que concerne à sua abrangência territorial, que abarca várias cidades da região centro do país com características geomorfológicas e sociais diversas, as questões da sustentabilidade assumem uma dimensão mais complexa e simultaneamente desafiante potenciando o desenvolvimento de abordagens inovadoras e adaptadas a cada realidade. (...) [Excerto] Boas Vindas João Pedro Silva [Pró-Presidente do Politécnico de Leiria]
- Storage Procedures Influence the Antioxidant Capacity of Bee PollenPublication . Orvalho, Telma; Vaz, Daniela C.; Campos, Maria; Santos Ribeiro, VâniaBee products, including bee pollen, are known for their therapeutic and nutritional properties due to the presence of several nutrients (essential lipids and amino acids, fat-soluble and water-soluble vitamins and bioelements) as well as natural antioxidants, such as flavonoids (e.g.: kaempferol, quercetin, and isorhamnetin), phenolic acids (chlorogenic acid) and catechins. Therefore, given its health beneficial properties, bee pollen is considered a valuable dietary supplement to the human diet, being currently marketed, and used as a food supplement. Nonetheless, the chemical and antioxidant properties of pollen can be altered by several factors, such as improper storage, type of sample handling and processing and sample ageing. Thus, we have evaluated the influence of different processing and conservation methods (freeze-drying, drying, and freezing) in the amount of total phenolics and antioxidant capacity present in 1-year samples, submitted to the different storing procedures. Total phenolic content (TPC) was estimated spectrophotometrically by using the Folin-Ciocalteu method and nuclear magnetic resonance spectroscopy (1H NMR); while the antioxidant capacity (AC) was determined by the ABTS (2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid)) and DPPH (2,2-Diphenyl-1-picrylhydrazyl) methods, that measure radical scavenging activities. Different solvent extraction procedures (ethanol and acetone based) were also applied to the several samples prior to analysis. The results showed that the antioxidant activity and total phenolics reduce considerably after one year of storage, especially when bee-pollen is submitted to freezing procedures.
- Preserving and hydrogel-matrixing the bioactive properties of aromatic medicinal halophytic herbs from the coastline of the Iberian PeninsulaPublication . Parracho, Tiago; Cruz, Pedro F.; Peralta, Claúdia C.; Silva, Cândida G.; Campos, Maria Jorge; Neves, Marta; Cordeiro, Rachel; Trindade, Daniela; Moura, Carla; Almeida, Zaida L.; Pereira, Cidália D.; Guimarães, Carla; Brito, Rui M. M.; Guerra, Mauro; Reboredo, Fernando; Veríssimo, Paula; Vaz, Daniela C.; Santos Ribeiro, VâniaEdible wild plants are part of the ethnobotanic heritage of a certain geographical area and are important sources of essential oils, antioxidants, minerals, and special flavours. Corema album (Portuguese crowberry), Crithmum maritimum (sea fennel), Eryngium maritimum (sea holly), Helichrysum italicum (curry plant) and Otanthus maritimus (cottonweed) wildly flourish along the sandy dunes of the coast of the Iberian Peninsula. These plants are locally known for their beneficial properties, with important value for food, cosmetics and/or medicinal applications. Hence, leaves of these endemic species were collected at four different locations and submitted to different preserving treatments (oven-drying, freezing, and freeze-drying). Acetonic extracts of the different plants submitted to the different post-harvesting treatments were analysed regarding their antioxidant capacities and phenolic contents. Plant extracts were also analysed by diffusion-ordered nuclear magnetic resonance spectroscopy (DOSY-NMR). In general, freeze-drying was the best method of preserving plant minerals, antioxidants (~4 mgVCEAC/g fw) and polyphenols (~5 mgGAE/g fw). Minerals were quantified via energy-dispersive X-ray fluorescence spectrometry, and despite their location, all plants were rich in Ca, Cl, K, S and P. Hierarchical clustering and principal component analyses (PCA) pointed towards chemical/metabolic proximity between taxonomic families. Alginate hydrogels loaded with 0.1 % and 0.2 % (w/v) of extracts presented homogenous surface properties by scanning electron microscopy, good mechanical tensile strength (~30 MPa) and antibacterial activity against S. aureus. Edible alginate hydrogels enriched with plant extracts hold great nutraceutical potential to be used as natural preservatives for food coating and packaging or as sources of bioactive compounds for biomedical applications.
- Edible flowers of Helichrysum italicum: Composition, nutritive value, and bioactivitiesPublication . Primitivo, Maria João; Neves, Marta; Pires, Cristiana L.; Cruz, Pedro F.; Brito, Catarina; Rodrigues, Ana C.; Carvalho, Carla C. C. R. de; Mortimer, Megan M.; Moreno, Maria João; Brito, Rui M. M.; Taylor, Edward J.; Millson, Stefan H.; Reboredo, Fernando; Campos, Maria; Vaz, Daniela C.; Santos Ribeiro, VâniaHelichrysum italicum (H. italicum) is a halophyte shrub with bright yellow flowers with a strong curry-like aroma. The essential oils of H. italicum have been used in the production of cosmetics and pharmaceuticals, due to their antiallergic and anti-inflammatory properties. In the agri-food sector, H. italicum flowers can be used for seasoning and flavoring food, and as natural food preservatives. Here, we report on the composition, bioactive compounds, and nutritive value of H. italicum flowers. Flowers were mainly composed of carbohydrates (>80 % dry weight), followed by minerals (6.31 ± 0.95 % dw), protein (5.44 ± 0.35 % dw), and lipids (3.59 % ± 0.53 % dw). High percentages of Fe, Zn, Ca, and K were found in the flower material, along with a high content in antioxidants, polyphenols, and carotenoids, as corroborated by the nuclear magnetic resonance (NMR) data. Flowers were mainly composed of saturated fatty acids (SFAs) (54.50 ± 0.95 % of total FA), followed by polyunsaturated fatty acids (PUFAs) (37.73 ± 1.25 % of total FA) and monounsaturated fatty acids (MUFAs) (7.77 ± 0.34 %), as detected by gas chromatography mass spectrometry (GC–MS). The omega-6 PUFA linoleic acid (22.55 ± 0.76 % of total FA) was the most abundant fatty acid found. Flower extracts showed antimicrobial activity against Saccharomyces cerevisiae and Komagataella phaffii, as well as against Gram-negative (Klebsiella pneumoniae) and Gram-positive (Staphylococcus aureus) bacteria. H. italicum flower material was nontoxic to human intestinal Caco-2 model cells at concentrations up to 1.0 % w/v.
- Oxidative Stability of Sunflower Oil Enriched with Fig Tree Leaves Bioactive Compounds at Frying TemperaturePublication . Pinteus, Susete; Neves, Marta; Tecelão, Carla; Silva, Susana; Cruz, Alexandra; Bernardino, Susana; Mendes, Vasco; Vaz, Daniela; Campos, Maria Jorge; Santos Ribeiro, VâniaThe pressure imposed by the increase of world’s population and climate change makes it imperative to find sustainable strategies to optimize food resources and decrease waste production based on circular economy principles. This work evaluated the potential of fig tree leaves to reduce the oxidation of sunflower oil when exposed to frying temperatures. The bioactive compounds extracted directly from fig tree leaves were incorporated into the oil at a ratio of 12.5% (m/m), with the assistance of ultrasounds. The supplemented oil was characterized in terms of its total phenolic content (TPC), which was determined using the Folin-Ciocalteu method, and its antioxidant capacity, which was evaluated using both the 2,2-Diphenyl-1-picrylhydrazyl (DPPH) assay and the ferric reduction antioxidant power (FRAP) assay. Also, the color of the oil and the oxidation products (K232 and K270) were analyzed. Supplementing the oil with fig tree leaves resulted in a higher antioxidant capacity compared to the control, as demonstrated by the DPPH assay (5128 ± 466 vs. 1106 ± 407 µM Trolox eq/kg oil), as well as lower levels of primary and secondary oxidation products. The results suggest that fig tree leaves can be a valuable source of antioxidant compounds with the capacity to improve the nutritional value and oxidative stability of sunflower oil under frying temperatures.
- Corema album spp: Edible wild crowberries with a high content in minerals and organic acidsPublication . Brito, Catarina; Bertotti, Taciana; Primitivo, Maria João; Neves, Marta; Pires, Cristiana L.; Cruz, Pedro F.; Martins, Patrícia A. T.; Rodrigues, Ana Cristina; Moreno, Maria João; Brito, Rui M. M.; Campos, Maria; Vaz, Daniela C.; Pessoa, Maria Fernanda; Lidon, Fernando; Reboredo, Fernando; Santos Ribeiro, VâniaEdible wild plants are part of the ethnobotanical and gastronomic heritage of different geographical areas. Corema album (L.) D. Don is an endemic species of the dune systems of the Atlantic coast of the Iberian Peninsula. The aerial parts of Corema album are a source of nutrients and antioxidants. The Corema album white berry (Portuguese crowberry) is rich in calcium, iron, and zinc. The plant also shows high phenolic content and antioxidant capacity associated with the leaves, fruit, and flowers. The presence of organic acids, namely phenolic acids, such as hydroxycinnamic acids, and long chain polyunsaturated fatty acids (PUFAs) omega-3 and omega-6 has also been confirmed. Toxicity studies evaluated by cell viability tests with human intestinal epithelium model cells (Caco-2) have shown that, at low concentrations, plant extracts may present beneficial effects.