Freshwater macrophytes include different groups of plants that are capable of growing in or very close to aquatic environments (spermatophytes, pteridophytes and bryophytes). These plants play a fundamental role in their ecosystems, regulating biogeochemical cycles, hydrology and sediment dynamic. Currently, many exotic freshwater macrophytes are being anthropogenically introduced into new ecosystems, posing a serious problem as a consequence of their massive and uncontrolled growth. Despite this, these plants can have different uses, such as biomarkers, phytoremediators, producers of metabolites of interest, or biomass formers for the production of feed, biofuels, pellets or ceramics. In this sense, the use of freshwater macrophytes in vivo, as fresh tissues, dry matter, compost, vermicompost, anaerobic digestate, liquid extracts or biochar has reported important benefits in different crops, promoting plant growth, increasing yield, reducing use of chemical fertilizers or reducing the diseases incidence. These benefits are the consequence of different mechanisms of action of the use of macrophytes as an agricultural resource, such as the contribution of nutrients, the improvement of the microbiota and soil structure, the elimination of heavy metals and pollutants, or the presence of antimicrobial compounds in their tissues. This review proposes the use of the biomass of these macrophytes, whose uncontrolled growth is an environmental problem, as an agricultural resource with important agricultural, environmental and economic benefits. A total of 118 published papers were analyzed and discussed.

Several mushroom species have been pointed out as sources of antioxidant compounds, besides their important nutritional value. Agaricus blazei and Lentinus edodes are among the most studied species all over the world, but those studies focused on their fruiting bodies instead of other presentations like powdered preparations used as supplements. In the present work the chemical composition (nutrients and bioactive compounds) and antioxidant activity (free radical scavenging activity, reducing power and lipid peroxidation inhibition) of dried powder formulations of the mentioned mushroom species (APF and LPF, respectively) were evaluated. Powder formulations of both species revealed the presence of essential nutrients such as proteins, carbohydrates and unsaturated fatty acids. Furthermore, they present low fat content (<2 g/100 g) and can be used in low-caloric diets, just like the mushrooms fruiting bodies. APF showed higher antioxidant activity and higher content of tocopherols and phenolic compounds (124 µg/100 g and 770 µg/100 g, respectively) than LPF (32 µg/100 g and 690 µg/100 g). Both formulations might be used as antioxidant sources to prevent diseases related to oxidative stress.

O presente trabalho decorreu em três albufeiras de idades distintas e sujeitas a diferentes tipos de perturbações de origem antropogénica. Estes sistemas aquáticos localizam-se na parte portuguesa da Bacia Hidrográfica do Rio Douro, na região de Trás-os-Montes. A albufeira da Serra Serrada foi criada em 1995 com o objectivo de abastecer de água a cidade de Bragança, actualmente com 34.750 habitantes. Como consequência do intenso consumo de água ocorrem flutuações de grande amplitude no seu nível. Por outro lado, na bacia de drenagem desta albufeira a pastorícia é particularmente intensa durante o Verão. Devido a esta actividade ocorrem nesta área, fogos frequentes que são induzidos pelos pastores com o objectivo de obterem melhores pastagens. A albufeira do Azibo encheu pela primeira vez em 1982. O seu objectivo inicial era o de irrigação no entanto, este projecto foi abandonado, e actualmente este sistema é essencialmente utilizado para fins recreativos durante os meses de Verão. Consequentemente, as flutuações no nível da água são insignificantes. A pastorícia e a agricultura são as principais actividades existentes na bacia de drenagem desta albufeira. Porém, a ocupação do solo é muito heterogénea para além dos solos agrícolas e dos prados, existem grandes extensões de matas autóctones, matos e matas ripícolas. A albufeira do Peneireiro foi criada em 1973 para abastecer a povoação de Vila Flor, actualmente com cerca de 7.760 habitantes. As flutuações no nível da água têm uma amplitude intermédia e a bacia desta albufeira é essencialmente ocupada por terrenos agrícolas. Na vizinhança deste sistema existe um parque de campismo e um circuito de manutenção. Durante o período de estudo as amostragens foram realizadas com uma periodicidade mensal no Inverno e quinzenal no Verão. Na albufeira do Peneireiro as amostragens foram realizadas sazonalmente pois, esta foi completamente esvaziada com o intuito de eliminar um bloom de Anabaena e Microcystis. O esvaziamento iniciou-se a partir de Agosto de 2000 e a albufeira só voltou a encher completamente em Abril de 2001. O objectivo deste estudo é contribuir para a caracterização limnológica destas albufeiras. Para atingir este objectivo, foram abordados os seguintes aspectos relacionados com: • Os efeitos da forma de ocupação do solo, do uso da água e da idade das albufeiras na qualidade da água dos sistemas estudados; • As consequências das flutuações extremas do nível da água nos valores de vários parâmetros ambientais registados na coluna de água e nas comunidades fito e zooplanctónicas; • A influência do regime de precipitação nos parâmetros ambientais e nas comunidades fito e zooplactónicas; • A identificação dos factores bióticos e abióticos que influenciam a composição e a estrutura das comunidades zooplanctónicas; • A actividade da fosfatase alcalina em albufeiras com características limnológicas distintas e localizadas em áreas com diferentes formas de ocupação do solo. A albufeira da Serra Serrada foi classificada como meso-eutrófica. As flutuações no nível da água e a consequente exposição dos sedimentos litorais a ciclos de dessecação/reinundação, a decomposição da vegetação de origem terrestre que foi inundada aquando da sua criação, a pastorícia e os fogos frequentes parecem ser as principais fontes de nutrientes e de matéria orgânica para a coluna de água. Os valores mais elevados do fósforo total, do fósforo solúvel reactivo, dos nitratos, da cor da água e da clorofila a obtiveram-se na fase em que o nível da água estava na sua cota mínima. Neste período o fitoplancton era dominado por espécies típicas de ambientes eutroficados. Durante a fase em que nível da água foi máximo foram também detectadas espécies que se encontram em ambientes oligotróficos. Os Rotifera e os Cladocera de pequena dimensão dominaram sempre o zooplancton, reflectindo por um lado, o elevado grau de perturbação deste ecossistema, e por outro, a provável ocorrência de predadores. No entanto, no final do Verão e durante o Outono o copépode Tropocyclops prasinus foi dominante em algumas das amostras obtidas. A albufeira do Azibo também foi classificada como meso-eutrófica. A agricultura, a pastorícia e as actividades recreativas foram consideradas como sendo as principais fontes externas de nutrientes e de matéria orgânica. Porém, as quantidades que entram na albufeira parecem ser influenciadas pela intensidade da precipitação. A comunidade zooplanctónica é dominada pelos Cladocera e pelos Copepoda. As espécies mais abundantes são: Daphnia longispina, Ceriodaphnia pulchella, Bosmina longirostris, Diaphanosoma brachyurum (Cladocera) e Copidodiaptomus numidicus (Copepoda). A estrutura deste comunidade parece assim, evidenciar os baixos níveis de perturbação existentes, e a provável quase ausência de predadores. As populações de cladóceros têm diferentes óptimos ecológicos. Daphnia é dominante durante o Inverno e o início da Primavera. No Verão Ceriodaphnia é a espécie mais abundante, coexistindo com Diaphanosoma. Esta última só é detectada nesta altura do ano. No início do Verão e no final do Outono Daphnia e Ceriodaphnia coexistem. Ao contrário dos outros taxa, Bosmina foi detectada durante todo o ano mas sempre em baixas densidades. Os dados obtidos indiciam que a temperatura é o principal factor que influencia a composição e a estrutura desta comunidade. Os macrófitos emergentes que ocorrem nas zonas litorais pouco profundas não são considerados importantes como refúgio ou zona de alimentação para as espécies mencionadas. A albufeira do Peneireiro foi classificada como eutrófica antes de ter sido esvaziada. As elevadas concentrações de fósforo total, de fósforo solúvel reactivo e de nitratos estão provavelmente relacionadas com as cargas provenientes das práticas agrícolas existentes na bacia de drenagem. O impacto destas práticas na qualidade da água é certamente potenciado pelas reduzidas áreas deste sistema e da sua bacia de drenagem. Após o reenchimento esta albufeira foi classificada como meso-eutrófica. A redução das concentrações de nutrientes observada durante esta fase é uma consequência da remoção da camada superior dos sedimentos. Apesar desta redução Anabaena ainda continuou a ser detectada nas amostragens subsequentes. A hidrólise dos fosfomonoésteres pela fosfatase alcalina não constitui um processo importante para a regeneração do ortofosfato nem na Serra Serrada nem no Azibo. Considerando os resultados das experiências baseadas no teste com Selenastrum capricornutum Printz, poder-se à inferir que o fósforo está sempre disponível em quantidades suficientes para o plancton, não sendo provavelmente limitante em nenhuma das albufeiras. Não foram detectadas, em nenhuma das albufeiras, correlações significativas entre a actividade da fosfatase e as concentrações de clorofila a. No entanto, verificou-se que a actividade desta enzima estava significativamente correlacionada com alguns géneros pertencentes ao fitoplancton. Na albufeira da Serra Serrada também foram detectadas correlações significativas entre a actividade da fosfatase e alguns dos crustáceos do zooplancton. No entanto, o mais plausível é que a fosfatase detectada em ambos os sistemas seja essencialmente produzida por bactérias envolvidas na decomposição.

Bee pollen is one of the richest and purest natural foods, used in the folk medicine, clinical practices, and food and pharmaceutical industries. This work aims to characterise, for the first time in Portugal, the palynological origin, nutritional value and microbiological safety of this beehive product. It identified ten botanical families, and the more frequent were Boraginaceae and Ericaceae. We have evaluated the water content, aw, pH, reducing sugars, ash, carbohydrate, proteins, lipids, fatty acids and energy. The microorganisms studied were the aerobic mesophiles, moulds and yeasts, faecal coliforms, Escherichia coli, Staphylococcus aureus, Salmonella and sulphite-reducing clostridia. The studied pollens are nutritionally well balanced, and contain high levels of moisture, proteins, fat, energy, ash, carbohydrates, reducing sugars, essential n-3 fatty acids and good ratios of polyunsaturated fatty acids (PUFA)/saturated fatty acids. In fact, the PUFA represent 66% of the total fatty acids. The samples had good microbiological quality, as none of the samples had toxigenic species.

The work described in this dissertation focuses on the methods for analyzing MS and ML that are used in PF. The purpose of the work is to investigate these methods on their practical application to a specific set of data. In the course of the work, the following tasks were completed: the current state of affairs in the field of PF was investigated, the theoretical foundations of the methods of MS and ML were investigated, which were subjected to practical tests on a specific set of data. Conclusions were drawn about the advantages and disadvantages of these methods. A selection of works of scientists engaged in research on the introduction of a specific set of nutrients into the soil was also investigated. The most important contributions to this work are the practical application of various methods of analysis, as well as the design of a DST designed to help farmers integrate PF into their pilot training farms.

Mushrooms contain a huge diversity of biomolecules with nutritional1 and/or bioactive properties.2 , 3 Morchella esculenta (L.) Pers. (morel) is one of the most widely appreciated wild edible mushrooms. Herein, a comparative study on chemical composition (nutritional value, primary and secondary metabolites), antioxidant properties (scavenging activity, reducing power and inhibiPEsttion of lipid peroxidation), and antimicrobial activity (antibacterial and demelanizing properties) of two samples of Mo r c h e l l a es c u l e n t a (morel) from different countries (Por tugal and Serbia) was performed. This species was chosen for being one of the most highly prized edible mushrooms in the world. Both samples are rich in carbohydrates (including free sugars) and proteins, and c o n t a i n seve r a l bi o - act ive compounds such as organic acids, phenolic compounds and tocopherols. Polyunsaturated fatty acids were the most abundant compounds followed by mono or saturated fatty acids. Sample from Portugal (SP) gave higher radical scavenging activity and reducing power, while sample from Serbia (SS) showed higher lipid peroxidation inhibition. Both samples gave antibacterial acti-vity against five b a c t e r ia (in some cases even bet ter than standard ant ibiot ics) and demelanizing activity against four micromycetes, showing SS higher activities. As far as we know, this is the first study reporting chemical compounds and bioactivity of morel samples from Por tu g a l an d Ser b i a . Furthermore, a novel method f o r ev a l u a t i o n of demelanizing activity was presented.

The nutritional and antioxidant composition of four tomato Portuguese farmer’ varieties widely cultivated in homegardens was determined. The analysed components included macronutrients, individual profiles of sugars and fatty acids by chromatographic techniques, hydrophilic antioxidants such as vitamin C, phenolics, flavonols and anthocyanins, and lipophilic antioxidants such as tocopherols, β-carotene and lycopene. Furthermore, the antioxidant activity was evaluated through DPPH scavenging activity, reducing power, beta-carotene bleaching inhibition and TBARS formation inhibition. One of the four varieties, which is locally known as round tomato or potato tomato, proved to be the most powerful in antioxidant activity (EC50 values ≤ 1.63 mg/ml), phenolic compounds (phenolics 31.23 mg ClAE/g extract, flavonols 6.36 mg QE/g extract and anthocyanins 3.45 mg ME/g extract) and carotenoids (β-carotene 0.51 mg/100 g and lycopene 9.49 mg/100 g), while the so-called yellow tomato variety revealed interesting nutritional composition, including higher fructose (3.42 g/100 g), glucose (3.18 g/100 g), alpha-linolenic acid (15.53%) and total tocopherols (1.44 mg/100 g) levels. Overall, these farmer’ varieties of garden tomato cultivated in the northeastern Portuguese region could contribute as sources of important antioxidants related to the prevention of chronic diseases associated to oxidative stress, such as cancer and coronary artery disease.

This study characterizes two species of the genus Hypericum to envisage their applicability as effective and versatile functional foods, dietary supplements, and food preservatives. A wide phenolic composition was found in both extracts, highlighting flanovoids for H. japonicum and xanthones for H. sampsonii. Moreover, anthocya- nins were analyzed for the first time in the latter plant. Antioxidant capacity was highlighted by oxidative he- molysis inhibition assay (OxHLIA), where H. japonicum was more effective (lower EC50) than antioxidant Trolox (16.3 < 21.8 μg/mL). H. sampsonii extract inhibited lipid peroxidation in the thiobarbituric acid reactive sub- stances (TBARS) method (EC50 = 17.05 μg/mL) compared to Trolox (EC50 = 5.8 μg/mL). H. japonicum anti- bacterial activity showed a minimum inhibitory concentration (MIC) of 0.007 mg/mL, even lower than the control. These results indicate the bioactive potential of both extracts, as well as the importance of evaluating the food-related bioactive components of medicinal plants and the mechanisms involved in their bioactivities.

Chestnuts are a widely consumed fruit around the world, being Portugal the fourth biggest producer in Europe. Storage of these nuts is an important step during processing, and the most widely used fumigant was banned in the European Union under the Montreal protocol due to its toxicity. Recently, radiation has been introduced as a cheap and clean conservation method. Previous studies of our research group proved that gamma radiation had no negative effect on the nutritional value of chestnuts; in fact, storage time had a much bigger influence on the chestnut quality. In the present study, we report the effect of a less ionizing radiation, electron beam, with doses of 0, 0.5, 1, 3 and 6 kGy in the nutritional value of chestnuts (ash, energy, fatty acids, sugars and tocopherols), previously stored at 4 ºC during 0, 30 and 60 days. The storage time seemed to reduce fat and energetic values but reported a tendency for higher values of dry matter. Regarding fatty acids, there was a higher detected quantity of C20:2 in non-irradiated samples, and four fatty acids were only detected in trace quantities (C6:0; C8:0; C10:0 and C12:0). γ-tocopherol decreased during storage time but did not alter its quantity for all the radiation doses (as like α-,β- and δ-tocopherol); in fact these compounds were present in higher concentration in the irradiated samples. Sucrose and total sugars were lower in non-irradiated samples and raffinose was only detected in irradiated samples. Electron beam irradiation seems to be a suitable methodology, since the effects on chemical and nutritional composition are very low, while storage time seems to be quite important in chestnut deterioration.

A comparative study on chemical composition (nutritional value, primary and secondary metabolites), antioxidant properties (scavenging activity, reducing power and inhibition of lipid peroxidation), and antimicrobial activity (antibacterial and demelanizing properties) of two samples of Morchella esculenta (morel) from different countries (Portugal and Serbia) was performed. This species was chosen for being one of the most highly prized edible mushrooms in the world. Both samples are rich in carbohydrates (including free sugars) and proteins, and contain several bioactive compounds such as organic acids, phenolic compounds and tocopherols. Polyunsaturated fatty acids were the most abundant compounds followed by mono or saturated fatty acids. Sample from Portugal (SP) gave higher radical scavenging activity and reducing power, while sample from Serbia (SS) showed higher lipid peroxidation inhibition. Both samples gave antibacterial activity against five bacteria (in some cases even better than standard antibiotics) and demelanizing activity against four micromycetes, showing SS higher activities. As far as we know, this is the first study reporting chemical compounds and bioactivity of morel samples from Portugal and Serbia. Furthermore, a novel method for evaluation of demelanizing activity was presented. Keywords: Morchella esculenta; Nutrients; Antioxidants; Antibacterial activity; Demelanizing activity. A comparative study on chemical composition (nutritional value, primary and secondary metabolites), antioxidant properties (scavenging activity, reducing power and inhibition of lipid peroxidation), and antimicrobial activity (antibacterial and demelanizing properties) of two samples of Morchella esculenta (morel) from different countries (Portugal and Serbia) was performed. This species was chosen for being one of the most highly prized edible mushrooms in the world. Both samples are rich in carbohydrates (including free sugars) and proteins, and contain several bioactive compounds such as organic acids, phenolic compounds and tocopherols. Polyunsaturated fatty acids were the most abundant compounds followed by mono or saturated fatty acids. Sample from Portugal (SP) gave higher radical scavenging activity and reducing power, while sample from Serbia (SS) showed higher lipid peroxidation inhibition. Both samples gave antibacterial activity against five bacteria (in some cases even better than standard antibiotics) and demelanizing activity against four micromycetes, showing SS higher activities. As far as we know, this is the first study reporting chemical compounds and bioactivity of morel samples from Portugal and Serbia. Furthermore, a novel method for evaluation of demelanizing activity was presented. Keywords: Morchella esculenta; Nutrients; ; Antibacterial activity; Demelanizing activity.

The search for foods that might improve health or reduce disease risk, has been progressively gaining interest. Mushroom could be examples of these foods, presenting the additional advantage of being recognized as a delicacy. This feature might place mushrooms in the pharma-nutrition interface. Herein, eight different mushroom species were characterized in terms of nutrients (proteins, carbohydrates, fat, individual sugars, fatty acids) and bioactive compounds (tocopherols, carotenoids, organic acids and phenolic compounds) with recognized antioxidant properties. These medicinal properties are often related with the antioxidant potential presented by mushroom extracts. Boletus regius was the species with the highest levels of carbohydrates (88.79 g/ 100 g dw) and PUFA (56.55%), bioactive compounds such as tocopherols (763.80 µg/100 g dw), citric acid (3.32 g/ 100 g dw) and phenolic compounds (23.49 mg/ 100 g dw), including two chrysin derivatives, presenting also the highest antioxidant activity. The identified bioactive compounds might be used as nutraceuticals to prevent chronic diseases related with oxidative stress. Furthermore, all tested species are edible, and could be incorporated directly in diet acting as functional foods.

Mushrooms contain a huge diversity of biomolecules with bioactive properties that should be explored. Morchella esculenta (L.) Pers. (morel) is one of the most highly prized edible mushrooms in the world. In the present work a comparative study on the chemical composition (nutritional value, primary and secondary metabolites) of the two samples from two countries, Portugal (SP) and Serbia (SS), was performed. Carbohydrates were the most abundant macronutrients, followed by proteins and ash. Fat contents were low and similar in both samples. The energetic contribution of SS was slightly higher due to the higher contribution of carbohydrates. Regarding the sugars, mannitol and trehalose were found in both samples, but fructose was only found in SP. Polyunsaturated fatty acids predominated over monounsaturated and saturated fatty acids. Linoleic, oleic and palmitic acids were abundant in both samples, but only SS gave considerable amounts of α- linolenic acid. Concerning the tocopherols, the α-, γ- and δ-tocopherols were also quantified in both samples; - and -tocopherols were observed in higher levels in SS. Oxalic and fumaric acids were in both samples; malic acid was found in SP, while quinic and citric acids were observed in SS. Finally, protocatechuic and phydroxybenzoic acids were found in both samples, but p-coumaric acid was quantified in SP. As far as we know, this is the first study reporting the chemical composition of morel samples from Portugal and Serbia.

Background/aims: This study aimed at evaluating whether patients with non-alcoholic steatohepatitis (NASH) had a specific dietary pattern and how it compared with data representative from the same geographical region individuals. Subjects and methods: Clinical, biochemical and anthropometrics: weight, height, body mass index (BMI) and waist circumference were collected in 45 NASH patients. Diet history was assessed using a validated semi-quantitative food frequency questionnaire, analysed with the Food Processor Plus, and was compared, after adjustment for BMI, with data from a sample of 856 free-living individuals, frequency matched for sex and age. Results: Patients' mean age was 49.6+/-10.6 years, 26 F: 19 M, BMI: 31.2+/-5.0 kg/m2. Comparison of their diet history with control data (C) revealed that carbohydrate consumption was lower in patients (P): P-243.6+/-5.7 g vs. C-261.5+/-1.6 g, P<0.05, and most patients had very low fibre intake. Conversely, total fat consumption was higher in patients: P-79.7+/-1.7 g vs. 73.0+/-0.4, P<0.01. A significantly higher intake of n-6 fatty acids (P=0.003) and n-6/n-3 ratio was found in patients, P<0.001. Conclusions: Our results suggest that the quality and combination of carbohydrates and fat intake may be more relevant than their isolated amount; an increased fat intake with an excessive amount of n-6 fatty acids can be implicated in promoting necro-inflammation, and provides further grounds for individualized dietary therapy.

Nutrients supplied via seabird guano increase primary production in some coastal ecosystems. A similar process may occur in the open ocean. To investigate this directly, we first measured bulk and leachable nutrient concentrations in guano sampled in the North Atlantic. We found that guano was strongly enriched in phosphorus, which was released as phosphate in solution. Nitrogen release was dominated by reduced forms (ammonium and urea) whilst release of nitrate was relatively low. A range of trace elements, including the micronutrient iron, were released. Using in-situ bioassays, we then showed that supply of fresh guano to ambient seawater increases phytoplankton biomass and photochemical efficiencies. Based on these results, modelled seabird distributions, and known defecation rates, we estimate that on annual scales guano is a minor source of nutrients for the surface North Atlantic. However, on shorter timescales in late spring/summer it could be much more important: Estimates of upper-level depositions of phosphorus by seabirds were three orders of magnitude higher than modelled aerosol deposition and comparable to diffusion from deeper waters.

Trace metal elements can cause various environmental and health issues due to their accumulation and integration in the food chain. In the present study, we determined the major toxic effects of arsenic on physiological behaviour of plants. For this propose, several combinations of high salinity and arsenic (As) concentrations were applied to the halophytic shrub, Tamarix gallica, by growing for three months with an irrigation solution supplemented with different concentrations of As (0, 200, 500 and 800M) with and without 200mM NaCl. The effect of the combined stress conditions on growth, physiological patterns and biochemical parameters were also assessed. The results demonstrated that T. gallica is a tolerant plant regarding arsenic. The photosynthesis apparatus Fo, Fm and Fv fluorescence, as well as Fv/Fm were not affected by As nor by As combined with salt. Likewise, pigment and nutrient (K+, Ca2+ and Mg2+) contents were not affected either. However, the study results revealed that As adversely and significantly influenced the growth with increasing the concentration of As. Despite shoots growth reduction, the present research demonstrates that T. gallica is able to cope with high external concentrations of As (under 500μM) alone or in combination with NaCl.

The Ria Formosa coastal lagoon is one of the most important and vulnerable ecosystems in Portugal, and it is subjected to strong anthropogenic pressures and natural nutrient inputs associated with coastal upwelling. The aim of this study was to evaluate the occurrence of nutrient and light limitation of phytoplankton growth during the productive period, and assess potential impacts of limitation on ecosystem eutrophication. Inorganic nutrients were added to natural microcosms filled with water collected at the landward and seaward boundaries, in summer 2012. Experimental treatments were incubated in situ under two different light intensities during 24 h. Phytoplankton composition, abundance and biomass, net growth rates and nutrient consumption were evaluated. At the landward location, potential nutrient limitation by nitrogen was observed. Nitrogen addition led to a significant increase in N consumption, resulting in higher phytoplankton growth, mainly diatoms, in all N-enriched treatments, under both light intensities. Significant consumption of silica and phosphorus was not reflected on growth, and it was probably due to luxury consumption. At the seaward station, phytoplankton, mainly cyanobacteria and eukaryotic picophytoplankton, were primarily limited by light, due to a deeper mixed layer. Nutrients were not limiting the phytoplankton growth due to import of nutrients from upwelled waters to the adjacent coastal zone.

A malnutrição é um desequilíbrio nutricional que afeta a saúde geral e oral dos indivíduos. A subnutrição resulta de uma ingestão insuficiente de nutrientes, a sobrenutrição decorre do excesso calórico, e a malnutrição específica deve-se à carência de micronutrientes essenciais. Todas impactam a saúde oral, enfraquecendo os tecidos, prejudicando a mineralização dentária e aumentando o risco de infeções e patologias gengivais. Este trabalho tem como objetivo examinar o impacto dessas diferentes formas de malnutrição na saúde oral das crianças, analisando as causas, os efeitos e as medidas de prevenção possíveis. Foram consultadas as bases de dados PubMed, ScienceDirect e Wiley online Library. Foram incluídos artigos de 2014-2024, em inglês, francês e português, sobre malnutrição infantil e saúde oral. A pesquisa abrangeu revisões narrativas e sistemáticas, meta-análises, estudos originais, relatos de caso, pesquisas em animais e sites governamentais. Excluíram-se estudos com amostras acima de 18 anos e crianças com doenças sistémicas. De acordo com as 53 publicações científicas, a obesidade infantil, que está a aumentar, resulta do consumo excessivo de açúcares e alimentos processados, associado ao sedentarismo e a fatores socioeconômicos, aumentando cáries, inflamações gengivais e patologias periodontais. A subnutrição, preocupante em contextos de crise, afeta crianças de famílias numerosas ou com alimentação limitada, causando atraso no crescimento dentário, fragilidade do esmalte e maior risco de cáries. Além disso, carências em proteínas, vitaminas e minerais, ligadas à subnutrição ou sobrenutrição, agravam esses problemas, reforçando a importância de uma alimentação equilibrada para a saúde oral infantil. A alimentação é essencial para a saúde oral infantil, mas os desafios modernos agravam a malnutrição.

As indústrias agroalimentares, incluindo a indústria pesqueira, produzem anualmente grandes quantidades de subprodutos cuja valorização ainda é mínima ou praticamente nula. Atualmente sabe-se que apenas uma pequena parte é reaproveitada para a alimentação direta de animais ou para compostagem. Tendo em conta que esses subprodutos contêm importantes teores de nutrientes e de compostos bioativos, são aqui referidas algumas vias alternativas de aproveitamento dos subprodutos provenientes da indústria pesqueira, nomeadamente para a indústria farmacêutica e cosmética. Não obstante, deve-se ter em conta a importância da sustentabilidade visto ser um conceito bastante complexo que envolve o desenvolvimento económico e social, sem provocar grandes danos ao ambiente e aos recursos naturais. Atualmente existem inúmeros casos de aproveitamento e consequente valorização de materiais que no passado eram rejeitados pelas indústrias agroalimentares e que devem servir de exemplo para todos os processos de produção alimentar, potenciando outras indústrias, como a farmacêutica. Assim, a utilização de recursos subaproveitados, com o objetivo de aumentar a produtividade e criar riqueza, terá de merecer, cada vez mais, maior atenção. A nível nacional, um dos setores mais importantes é o da pesca. Atendendo à importância que a indústria pesqueira exerce a nível nacional e internacional, tentou-se, neste trabalho, caracterizar e valorizar os subprodutos gerados por esta atividade, através de uma descrição detalhada da caracterização nutricional, química e das propriedades biológicas dos constituintes presentes nestes resíduos e que podem beneficiar, num futuro próximo, a indústria farmacêutica e cosmética.

O presente trabalho apresenta uma revisão da literatura que evidencia a importância nutricional, fitoquímica e propriedades biológicas das sementes de melancia. Neste trabalho de revisão bibliográfica foram descritos os principais nutrientes, compostos antioxidantes das sementes, tais como ácidos fenólicos, flavonoides, alcaloides, bem como a sua associação às atividades biológicas benéficas que os mesmos poderão exercer no metabolismo humano. Foi possível concluir que as sementes de melancia são fontes de proteínas, ácidos gordos essenciais, vitaminas e minerais. As propriedades funcionais e medicinais são atribuídas à presença de compostos bioativos como ácidos fenólicos, flavonoides, carotenoides e alcaloides, que são excelentes fontes de antioxidantes naturais. As sementes desta fruta, apesar de terem valor nutricional e energético, são geralmente descartadas como subproduto alimentar. Recentemente, o uso potencial de subprodutos alimentares no desenvolvimento de novos ingredientes saudáveis para o enriquecimento de alimentos tem sido uma forma de reduzir a poluição e garantir a sustentabilidade ambiental. Conclui-se assim que, pelo seu teor nutricional, composição química, propriedades biológicas e farmacológicas descritas, estas podem ser adicionadas aos alimentos para os enriquecer, utilizadas como suplemento alimentar e até incorporadas em fármacos, bem como utilizadas na cosmética.

A dieta alimentar permite ao indivíduo consumir diariamente substâncias nutritivas fundamentais para o seu desenvolvimento e sobrevivência. Contudo, quando a sua ingestão é nutricionalmente desequilibrada ou escassa, o metabolismo humano poderá atingir um estado de desnutrição e, consequentemente promover o aparecimento de distúrbios metabólicos e/ou doenças crónicas. Com a consciencialização destes problemas verificou-se, nos últimos anos, uma crescente tendência para o consumo de alimentos funcionais ou substâncias nutracêuticas. Muitos destes alimentos e ingredientes são de origem vegetal, apresentando elevados teores de fibras, vitaminas, minerais, ácidos gordos polinsaturados, proteínas, compostos bioativos, entre outros. Consequentemente, uma maior atenção tem sido dada à utilização de subprodutos vegetais, onde se incluem as sementes, as quais na sua maioria não são utilizadas pela indústria alimentar nem pela população em geral. O reaproveitamento das sementes acarreta maior valor económico à produção agrícola, além de contribuir para a formulação de novos produtos alimentares e diminuir o desperdício industrial. Neste trabalho propôs-se efetuar uma revisão bibliográfica sobre o aporte nutricional e propriedades biológicas de algumas sementes (abóbora, cânhamo, chia, linhaça, papoila e quinoa) atualmente introduzidas como ingredientes ou alimentos, as quais têm tido elevada aceitação por parte do consumidor em geral.