The uptake of macronutrients by an active silicon accumulator plant growing in two different substrata

Pennisetum clandestinum (Graminae/Poaceae) an active Si-accumulator, was cultivated in two different substrata, both with reduced Si solubility. Plants growing in organic-rich soils contained much less Ca, K, Na and Si, than species growing in sandy soils. Although the highest macronutrient concentrations were associated to the highest Si levels in the organs of P. clandestinum, the R correlation values indicate that Si does not influence the internal balance and the uptake of these elements. In ca 65% of the cases roots have the highest average values regardless of the type of culture, while the contents of Mg in the shoots and roots of P. clandestinum were generally not significantly different (P>0.05). A significant decline of the macronutrient levels associated to the shoots and roots of P. clandestinum was observed from the 4th to the 6th month assay, especially for Ca in both organs, while for Mg and Na the decline is focused mainly in the shoots; K and Si decline is generally below 10%. When average values of Si in shoots and roots of plants collected from organic- rich and sandy soils were plotted against the average concentrations of Ca, K, Mg and Na in the same organs, weak but positive R correlation values were obtained - the highest R values were observed for Na and K and the lowest for Ca and Mg, regardless of the culture. Exception for the high R value observed for K, although the influence of Si on the K status in the whole plant is time-depending - R values, diminished from the 4th to the 6th month, as it happens in the majority of the cases. In conclusion, P. clandestinum can grow well and healthily in substrata with acid pH values and high carbonate content and low solubility of Si suggesting that the definition of the essentiality of Si, even in a Si-accumulator plant is still a matter of great controversy.publishersversionpublishe

Nutritional profile of the Portuguese cabbage (Brassica oleracea L var. costata) and its relationship with the elemental soil analysis

The 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.publishersversionpublishe

An integrated chemical and technological approach for assessing Portuguese wheat flours quality and lengthening bread shelf-life

UID/GEO/04035/2019 UID/AGR/04129/2019The current trend of large-scale bread production is to facilitate processing at an industrial level, considering the use of flour mixtures with different chemical and technological parameters and incorporating food additives. Accordingly, costs can be minimized, whereas the quality and the shelf-life of the final product might increase, but a full characterization of the flours that must be used and the selection of the food additives to be incorporated into the dough is required. In this context, three Portuguese wheat flour varieties were evaluated (FariRamos, Nacional and AJMiranda), as well as two types of food additives with the aim to increase bread shelf-life. In these flours, the levels of K, S, P, Ca and Cl prevailed, but the moisture and ash contents of FariRamos were the highest and lowest, respectively. The colour of all flours was generally within the desired standard values. Nacional flour contained a higher fat content, but all the flours showed a higher relative abundance of linoleic acid (C18:2), followed by palmitic acid (C16:0) and oleic acid (C18:1). AJMiranda flour revealed a higher content of wet gluten and protein, but the SDS sedimentation index showed a higher value in the FariRamos flour. The fall index, which directly monitors the activity of the α-amylase enzyme, showed a lower value in AJMiranda and Nacional. Through farinograph and alveographyc analysis it was found that FariRamos has a tenacious gluten, but AJMiranda and Nacional had a balanced gluten, yet all of them can be classified as medium flours. Bread making with a mix of FariRamos, AJMiranda and Nacional flours and incorporating preservative food additives revealed the highest shelf-life (11-days) with methyl p-hydroxybenzoate [0.05 %] and benzoic acid [0.1 %], but the colour of the breads showed a relationship of intensity of white colour that depended on the additive used. At the end of the shelf-life, molds of the Eurotium, Trichoderma and Cladosporium genera developed in the bread. It was concluded that the chemical and technological approach applied in the characterization of the flour varieties, can be directly used to define the quality and shelf-life in the bakery industry, allowing the establishment of minimum commercialization prices.publishersversionpublishe

ACUMULAÇÃO DE METAIS PESADOS E ALTERAÇÃO DAS PROPRIEDADES FÍSICAS E QUÍMICAS DE AREIAS DE DUNAS LITORÂNEAS

Nos dois últimos séculos, na orla costeira de Portugal, generalizou-se a prática agrícola em areias de duna com a aplicação de agroquímicos, sem controlo técnico, de onde resultaram alterações da composição físico-química e acumulação de metais pesados nas areias. Com o objetivo de avaliar os efeitos do manejo agrícola foram coletadas e caracterizadas, do ponto de vista físico e químico, amostras das dunas, entre os 0,0 cm e os 20 cm de profundidade, com e sem prática agrícola. Foi determinada, por ensaio de peneiramento, a fração fina (partículas com diâmetro inferior a 0,074 mm) e pelo método MAB – Peróxido a composição em matéria orgânica. Foi estimada a umidade das amostras e determinado, pelo método eletroquímico, o pH, a condutividade elétrica e o potencial de oxirredução. A composição química foi analisada por fluorescência de raios-x. Verificou-se que o manejo agrícola das dunas resultou no aumento da fração fina, da matéria orgânica, da umidade, da condutividade elétrica e do potencial de oxirredução das areias. O pH diminuiu, de básico para valores próximos de neutro, aumentando o risco de acumulação e mobilização de Fe, Mn, Cu, Zn, Pb, As, Zr, Th, Rb, Cr, V, Ni, Hg, Co e U

Mineral Monitorization in Different Tissues of Solanum tuberosum L. during Calcium Biofortification Process

Funding Information: This work received funding from PDR2020-101-030719 and the Fundação para a Ciência e a Tecnologia, I.P. (FCT), Portugal, through the research units UIDP/04035/2020 (GeoBioTec), UIDB/00239/2020 (CEF), and UID/FIS/04559/2013 (LIBPhys). This work was further supported by the grant of the Fundação para a Ciência e Tecnologia (FCT) UI/BD/150806/2020. Publisher Copyright: © 2022 by the authors.Calcium is one of the 16 essential elements for plants, being required as Ca2+ and being involved in several fundamental processes (namely, in the stability and integrity of the cell wall, the development of plant tissue, cell division, and in stress responses). Moreover, Ca plays an important role in potato production. In this context, this study aimed to monitor the culture development (in situ and using an unmanned aerial vehicle (UAV)) and the mineral content of four essential elements (Ca, P, K, and S) in different organs of Solanum tuberosum L. (roots, stems, leaves, and tubers) during a calcium biofortification process, carried out with two types of solutions (CaCl2 and Ca-EDTA) with two concentrations (12 and 24 kg∙ha−1). The calcium content generally increased in the S. tuberosum L. organs of both varieties and showed, after the last foliar application, an increase in Ca content that varied between 5.7–95.6% and 20.7–33%, for the Picasso and Agria varieties, respectively. The patterns of accumulation in both varieties during the biofortification process were different between the variety and mineral element. Regarding the quality analysis carried out during the development of the tubers, only the Agria variety was suitable for industrial processing after the last foliar application.publishersversionpublishe

Macaronesia Acts as a Museum of Genetic Diversity of Relict Ferns: The Case of Diplazium caudatum (Athyriaceae)

Macaronesia has been considered a refuge region of the formerly widespread subtropical lauroid flora that lived in Southern Europe during the Tertiary. The study of relict angiosperms has shown that Macaronesian relict taxa preserve genetic variation and revealed general patterns of colonization and dispersal. However, information on the conservation of genetic diversity and range dynamics rapidly diminishes when referring to pteridophytes, despite their dominance of the herbaceous stratum in the European tropical palaeoflora. Here we aim to elucidate the pattern of genetic diversity and phylogeography of Diplazium caudatum, a hypothesized species of the Tertiary Palaeotropical flora and currently with its populations restricted across Macaronesia and disjunctly in the Sierras de Algeciras (Andalusia, southern Iberian Peninsula). We analysed 12 populations across the species range using eight microsatellite loci, sequences of a region of plastid DNA, and carry out species-distribution modelling analyses. Our dating results confirm the Tertiary origin of this species. The Macaronesian archipelagos served as a refuge during at least the Quaternary glacial cycles, where populations of D. caudatum preserved higher levels of genetic variation than mainland populations. Our data suggest the disappearance of the species in the continent and the subsequent recolonization from Macaronesia. The results of the AMOVA analysis and the indices of clonal diversity and linkage disequilibrium suggest that D. caudatum is a species in which inter-gametophytic outcrossing predominates, and that in the Andalusian populations there was a shift in mating system toward increased inbreeding and/or clonality. The model that best explains the genetic diversity distribution pattern observed in Macaronesia is, the initial and recurrent colonization between islands and archipelagos and the relatively recent diversification of restricted area lineages, probably due to the decrease of favorable habitats and competition with lineages previously established. This study extends to ferns the concept of Macaronesia archipelagos as refugia for genetic variation

Quantification and tissue localization of selenium in rice (Oryza sativa l., poaceae) grains: A perspective of agronomic biofortification

grant number 101-030671In worldwide production, rice is the second-most-grown crop. It is considered a staple food for many populations and, if naturally enriched in Se, has a huge potential to reduce nutrient deficiencies in foodstuff for human consumption. This study aimed to develop an agronomic itinerary for Se biofortification of Oryza sativa L. (Poaceae) and assess potential physicochemical deviations. Trials were implemented in rice paddy field with known soil and water characteristics and two genotypes resulting from genetic breeding (OP1505 and OP1509) were selected for evaluation. Plants were sprayed at booting, anthesis and milky grain phases with two different foliar fertilizers (sodium selenate and sodium selenite) at different concentrations (25, 50, 75 and 100 g Se·ha−1). After grain harvesting, the application of selenate showed 4.9–7.1 fold increases, whereas selenite increased 5.9–8.4-fold in OP1509 and OP1505, respectively. In brown grain, it was found that in the highest treatment selenate or selenite triggered much higher Se accumulation in OP1505 relatively to OP1509, and that no relevant variation was found with selenate or selenite spraying in each genotype. Total protein increased exponentially in OP1505 genotype when selenite was applied, and higher dosage of Se also increased grain weight and total protein content. It was concluded that, through agronomic biofortification, rice grain can be enriched with Se without impairing its quality, thus highlighting its value in general for the industry and consumers with special needs.publishersversionpublishe

Sweetener Food Additives: A Synoptical Overview on Their Chemical Properties, Applications in Food Products and Side Effects

The increase of obesity and its metabolic comorbidities have led to a growing consumption of sugar-free products, where sucrose is replaced by low-calorie sweeteners. Since the discovery of the synthesis of saccharin, progressively more non-nutritive sweeteners have been produced and consumed, as they release none or only very small amounts of energy. In this context, traditional synthetic food sweeteners are largely used, because they have a higher sweetener power than most of the sweeteners of natural origin. Yet, due to their potential risks, some of them are being replaced by those obtained from natural origins with high sweetening power, such as thaumatins and neohesperidin DC, or by synthetic sweeteners with an even greater sweetener power, with advantame as the one with the highest sweetening power. Yet, numerous side effects of synthetic sweeteners have been reported (namely, stomach and liver problems, allergic reactions, nausea, vomiting, changes in behaviour, cognitive problems, genotoxicity and carcinogenic effects), whereas those naturally derived seem to have less important health problems associated. Moreover, some sweeteners of natural origin, such as polyols, have a low sweetening power, which makes them less effective, but have other functions in food processing. To further understand the implications of using synthetic and natural-derived food sweeteners, this review aims to provide a synoptical approach on chemical characteristics, properties, uses and side effects of those which are currently allowed and applied during food processing mostly considering the authorized sweeteners in European Union.Keywords: Side effects of sweeteners; Sweetener food additives; Sweeteners of natural origin; Sweeteners of synthetic origin; Sweeteners application

A Synoptical Overview on Their Chemical Properties, Applications in Food Products and Health Side Effects

Funding Information: Funding: This research was funded by national funds from Fundação para a Ciência e a Tecnologia (FCT), Portugal, through the research unit UIDP/04035/2020 (GeoBioTec). Funding Information: This research was funded by national funds from Funda??o para a Ci?ncia e a Tecnologia (FCT), Portugal, through the research unit UIDP/04035/2020 (GeoBioTec). Publisher Copyright: © 2022 by the authors. Licensee MDPI, Basel, Switzerland.Colour is one of the most relevant organoleptic attributes that directly affects consumers’ acceptance and food selection. However, as food colouring pigments are generally unstable and become modified during processing, in order to maintain or restore product colour uniformity, colourants are added to food products around the world. In this context, although they are still widely used, synthetic food colorants, due to their potential hazards, are being replaced by those obtained from natural origins. Indeed, numerous side effects and toxicities, at both the medium and long-terms—namely allergic reactions, and behavioral and neurocognitive effects—have been related to the use of synthetic colourants, whereas their naturally-derived counterparts seem to provide a somewhat high-quality and effective contribution as a health promoter. In order to further understand the implications of the use of synthetic and naturally derived food colourants, this review aims to provide a synoptical approach to the chemical characteristics, properties, uses and side effects on health of those which are currently allowed and applied during food processing.publishersversionpublishe