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Pine nut skin (PNS) is an unexploited and uncharacterized by-product recovered during pine nut processing. The exploitation of by-products as sources of valuable compounds agrees with the current demand for the reduction of waste, and a transition to more sustainable production and consumption1. Therefore, PNS characterization and bioactive potentialities were assessed. The utilization of several chromatographic techniques allowed the characterization of PNS phenolic compounds (HPLC-DAD-UV and HPLC-DAD-ESI-MSn), and the carbohydrates quantification and structural characterization, after specific derivatization (GC-FID and GC-MS). PNS subcritical water extraction using microwave was optimized and the obtained extracts, separated into low-molecularweight (rich in phenolic compounds) and high-molecular-weight (rich in carbohydrates), were evaluated regarding their digestibility and prebiotic activity. The prebiotic potential was assessed by quantifying the short-chain fatty acids (HPLC-UV) produced after the in vitro faecal fermentation. HPLC-DAD-ESI-MSn allowed to identify PNS phenolic compounds, namely protocatechuic, p-coumaric, and caffeic acids, while HPLC-DAD-UV enabled the monomers identification of proanthocyanidins ((epi)catechins) and hydrolysable tannins (protocatechuic acid), after acid methanolysis. GC techniques allowed to disclose the polysaccharides structures (xyloglucans and pectic polysaccharides) and their degradation by microbiota. The fermentation of both extracts rich in phenolic compounds and rich in polysaccharides resulted in an increased production of acetic, propionic, and butyric acids when compared to the commercial prebiotic inulin, proposing these PNS extracts as prebiotic agents., The work was supported through the projects UIDB/50006/2020 and UIDP/50006/2020, funded by FCT/MCTES through national funds. Soraia P. Silva, Alondra González and Dalila Roupar thank FCT/MCTES and ESF through NORTE 2020 for their PhD grants (ref. SFRH/BD/136471/2018, SFRH/BD/06268/2021 and SFRH/DB/139884/2018 respectively). Elisabete Coelho thanks the research contract (CDL-CTTRI-88-ARH/2018 – REF. 049-88-ARH/2018) funded by national funds (OE), through FCT, in the scope of the framework contract foreseen in the numbers 4, 5 and 6 of the article 23, of the Decree-Law 57/2016, of August 29, changed by Law 57/2017, of July 19. Clarisse Nobre acknowledges FCT for the assistant research contract 2021.01234.CEECIND., info:eu-repo/semantics/publishedVersion

Book of Abstracts of CEB Annual Meeting 2017, [Excerpt] The development of injectable bone substitutes (IBS) have garnered great importance in the bone regeneration field, as a strategy to reach areas of the body using minimally invasive procedures, and showing the ability of perfect fitting according to irregularities of bone tissue defects. In this context, the combination of injectable hydrogels and ceramic granules is emerging as a well-established trend. Particularly, in situ gelation hydrogels have arisen as a new IBS generation. [...], info:eu-repo/semantics/publishedVersion

His book focuses on process simulation in chemical engineering with a numerical algorithm based on the moving finite element method (MFEM). It offers new tools and approaches for modeling and simulating time-dependent problems with moving fronts and with moving boundaries described by time-dependent convection-reaction-diffusion partial differential equations in one or two-dimensional space domains. It provides a comprehensive account of the development of the moving finite element method, describing and analyzing the theoretical and practical aspects of the MFEM for models in 1D, 1D+1d, and 2D space domains. Mathematical models are universal, and the book reviews successful applications of MFEM to solve engineering problems. It covers a broad range of application algorithm to engineering problems, namely on separation and reaction processes presenting and discussing relevant numerical applications of the moving finite element method derived from real-world process simulations.

The objective of this work was to estimate the genetic variability level and distribution in Brazilian broodstocks of marine shrimp (Litopenaeus vannamei). Nine of the country?s largest hatcheries were evaluated using codominant and highly polymorphic microsatellite markers. The results obtained from genotyping of ten microsatellite loci are indicative of genetic variability that is compatible with that found in wild populations of L. vannamei in Mexico and Central America. A possible explanation is the highly diversified and relatively recent origin of the available broodstocks. Bayesian analysis detected a signal for five founding populations. The distribution of genetic distances partially reflects geographical location, and this information will be useful for the creation of new broodstocks. Therefore, L. vannamei genetic variability among nine of the largest national hatcheries can be considered high.

info:eu-repo/semantics/publishedVersion

Layer-by-Layer (LbL) assembly is based on the electrostatic interaction between oppositely charged polyelectrolytes alternatively adsorbed onto an appropriate template. Nanocapsules prepared through LbL can be specially engineered with controlled sizes, composition, and functionality, and can be used as carriers for bioactive compounds. Chitosan, a cationic polysaccharide with antimicrobial activity, and fucoidan, an anionic sulfated polysaccharide with various bioactive properties (such as antioxidant activity), are candidates for the formation of functional multilayers. The present work aims at developing biodegradable hollow nanocapsules through LbL assembly of chitosan and fucoidan. Nanocapsules were built through the alternate deposition of 10 chitosan/fucoidan layers on polystyrene (PS) nanoparticles (diameter 100 nm), used as templates, followed by removal of the PS core. The obtained multilayer nanocapsules were characterized by means of dynamic light scattering (DLS) (size and zeta potential), quartz crystal microbalance (QCM) measurements, Fourier transform infrared (FTIR), and scanning electron microscopy (SEM). Zeta potential values indicated the stepwise deposition of chitosan and fucoidan alternating layers on the PS nanoparticles. The real-time build-up of chitosan and fucoidan nanolayered assemblies was monitored by QCM and a frequency decrease was observed after each polyelectrolyte deposition, indicating that mass was being deposited, and also the adsorption equilibrium was attained and stable layers were obtained. DLS measurements and SEM showed that the size of the nanocapsules is in the order of a few hundreds of nanometers. The removal of the PS templates from the core-shell particles was confirmed by the disappearance of the characteristic bands (at 3000-3103, 756 and 698 cm -1) of the PS residue in the FTIR spectrum. Chitosan/fucoidan capsules are envisaged as a nanocarrier system (for example, oxidation-sensitive active compounds, which would benefit from the shelter provided by the capsules). Such systems have possible applications in food and pharmaceutical industries., info:eu-repo/semantics/publishedVersion

In this work, the effect of high hydrostatic pressure (HHP) treatment of wine, as substitute of SO2, was evaluated by quantification of microbial load, antioxidant capacity, and colour. For this purpose, red wine of two consecutive harvests (2008 and 2009) was produced without the addition of SO2. At the end of the alcoholic fermentation, the wine was pressurized at 350 MPa for 20 min at 20 ºC. After nine months of storage, the wine submitted to HHP showed no growth of yeasts and bacteria. However, differences in colour and antioxidant activity were observed in pressurized wine from 2009 but not in pressurized wine from 2008, when compared to the wine with SO2. These results show that although HHP technology has already been proposed for wine pasteurization, more studies concerning its effect on wine, towards the use of HHP to reduce SO2 in wine making, are still required. Dans ce travail, l'effet du traitement avec pression hydrostatique élevée (PHE) au vin, comme substitut du SO2, a été évalué par la quantification de la croissance microbienne, la capacité anti-oxydante et la couleur. Pour cet effet, un vin rouge de deux récoltes consécutives (2008 et 2009) a été produit sans addition de SO2. À la fin de la fermentation alcoolique, le vin a été pressurisé à 350 MPa pendant 20 min à 20º C. Le vin soumis à PHE n'a montré aucune croissance de levures et de bactéries après la pressurisation. Toutefois, il a été observé, après neuf mois de stockage, des différences de couleur et d’activité anti-oxydante dans le vin de 2009 pressurisé, mais pas dans le vin de 2008 pressurisé, par rapport au vin avec SO2. Ces résultats montrent que même si la technologie de PHE a déjà été proposée pour la pasteurisation du vin, d’autres études de son effet sur le vin sont nécessaires pour que cette technique puisse être utilisée comme un substitut du SO2 dans la vinification.

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Brewers´ spent grain (BSG) is a by-product from beer industry that can be exploited as a source of arabinoxylo-oligosaccharides (AXOS) with prebiotic activity. In this study, microwave-assisted extractions were performed during 2 min at 140-210°Cin order to evaluate the feasibility of this extraction technology for quantitative extraction of the arabinoxylans (AX) or AXOS from BSG. The AX yield increasedwith the increase of the temperature in the range used. The best condition of extraction of the AXwas 210 ºC during 2 min, allowing the extraction of 43% of total AX. These AX showed structural variability which allow to define specific types of compounds for different applications and uses depending on the extraction conditions used.

A adição de sulfuroso nas diferentes etapas de vinificação tem por objectivo impedir o crescimento de microrganimos nocivos ao vinho, bem como actuar como antioxidante, mantendo as características sensoriais do vinho. Contudo, os produtores têm procurado reduzir a utilização de sulfuroso dada a sensibilidade alérgica a este composto por cerca de um terço dos consumidores. Neste trabalho foram testados diferentes tratamentos com o objectivo de desenvolver tecnologias para a substituição total ou parcial do sulfuroso adicionado na vinificação. Foram estudados três tratamentos diferentes em vinho branco de forma isolada e em combinação: adição de um sesquiterpenóide, adição de quitosana e a utilização da tecnologia de alta pressão hidrostática. Para fins de comparação, também foi preparado e analisado um vinho com sulfuroso e outro sem nenhum tipo de tratamento. Os vinhos tratados com quitosana e alta pressão, ao fim de um mês de armazenamento, ainda apresentavam ausência de leveduras. Contudo, no vinho sem tratamento e no vinho em que só foi adicionado o sesquiterpenóide verificou-se crescimento de leveduras (5x1 04-6x1 o4 UFCJmL). A actividade antioxidante foi superior no vinho branco tratado com o sesquiterpenóide (28%), quitosana (30%) e alta pressão (35%) em comparação com o vinho sem tratamento e com valores semelhantes ao vinho tratado com sulfuroso. Estes resultados preliminares mostram que a adição do sesquiterpenóide ou quitosana e a utilização da tecnologia de alta pressão, são tratamentos promissores como substituintes das propriedades de conservação conferidas pelo sulfuroso aos vinhos.

A adição de sulfuroso nas diferentes etapas de vinificação tem por objectivo impedir o crescimento microbiológico de espécies nocivas ao vinho, assim como actuar como antioxidante, mantendo as características sensoriais do vinho. Contudo, os produtores têm procurado reduzir a utilização de sulfuroso dada a sensibilidade alérgica a este composto por cerca de um terço dos consumidores. Neste trabalho, testaram-se três tratamentos diferentes com o objectivo de desenvolver tecnologias para a substituição total ou parcial do sulfuroso: (1) adição de um sesquiterpenóide, (2) adição de uma quitosana e (3) utilização da tecnologia de alta pressão hidrostática. Para este estudo foram utilizados dois vinhos, um tinto e um branco, e os tratamentos seleccionados foram efectuados no fim da fermentação alcoólica. A eficácia dos tratamentos como substituintes do sulfuroso na actividade anti-microbiana e antioxidante em vinhos, assim como na cor, foi avaliada ao longo do armazenamento. Ao fim de três meses de armazenamento os vinhos brancos e tintos tratados com quitosana e alta pressão não apresentavam crescimento de leveduras e bactérias. No entanto, no vinho sem tratamento e no vinho em que só foi adicionado o sesquiterpenóide verificou-se crescimento de leveduras (5 -8x103 UFClmL). A actividade antioxidante foi superior nos vinhos tratados com sesquiterpenóide (30-40%), quitosana (15-25%) e alta pressão (45%) em comparação com o vinho sem tratamento. No vinho tinto não se verificaram alterações na cor com os tratamentos, enquanto que no vinho branco se observou uma intensidade de cor inferior para os vinhos tratados por adição de sesquiterpenóide e aplicação de alta pressão em relação ao vinho sem tratamento. Embora ainda preliminares, estes resultados mostram que a adição do sesquiterpenóide ou da quitosana, assim como a utilização da tecnologia de alta pressão hidrostática são tratamentos promissores como substituintes das propriedades de conservação conferidas pelo sulfuroso aos vinhos.

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Polysaccharides are one of the main components of bacterial cell walls. With the intent of formulating a multivalent Helicobacter pylori lipopolysaccharide-based vaccine, several studies have been carried by Monteiro and coworkers in order to understand the structural variability of H. pylori cell-surface glycans. It is now well documented that H. pylori produces cell-surface lipopolysaccharides (LPSs) composed of structures homologous to mammalian blood group antigens [1], termed “Lewis O-chains,” that are thought to play a role in H. pylori pathogenesis. These studies have also demonstrated that wild-type H. pylori LPS isolates contain small amounts of mannose, but, so far, a mannose-rich polysaccharide was only detected in a LPS mutant strain [2]. In this work we observed that wild-type H. pylori strain 968 produces a mannose-rich polysaccharide coexpressed with a “Lewis O-chain” polysaccharide. Fine structural studies comprising chemical and spectroscopy methods demonstrated that this mannan is composed of a linear backbone of α-(1→2)-linked mannose units in which approximately 50% is substituted at the O-6 position. This mannan may represent an H. pylori-specific exopolysaccharide that may be expressed by many strains.

Os polissacarídeos da parede celular de Ameixas d'Elvas ("Rainha Claudia Verde") provenientes de dois pomares de fenótipo semelhante, Vila Viçosa e Cano, mas que dão origem a ameixas confitadas com texturas muito diferentes, foram estudados, e quantificada a actividade das enzimas associadas à sua degradação. A análise dos polissacarídeos, por extracção sequencial, mostrou que as ameixas do pomar do Cano possuíam polissacarídeos pécticos mais facilmente solubilizados em água e polissacarídeos hemicelulósicos também mais solúveis em soluções alcalinas, do que as ameixas do pomar de Vila Viçosa. A quantificação das actividades das enzimas pectinametilesterase (PME), poligalacturonase (PG) e celulase (Cel) revelou que na altura da colheita para processamento, as ameixas do pomar do Cano tinham uma actividade inferior de PME e superior de PG e Cel, relativamente às do pomar de Vila Viçosa. A perda de firmeza dos fi-utos do pomar do Cano parece estar relacionada com um estado de maturação bioquírnico mais adiantado, que não é detectável pelos parâmetros convencionais de avaliação da maturação.

Helicobacter pylori is a widespread Gram-negative bacterium that infects the stomach of humans leading to the onset of several gastric disorders, such as, gastritis, gastric ulcers, and cancers. Studies from developing countries with low socioeconomic status and poor management of the drinking water suggest that it may serve as an environmental reservoir of H. pylori and therefore contribute to human infection. It has been reported that H. pylori has the ability to form microbial consortia embedded by a highly hydrated exopolysaccharidic matrix (biofilms) on surfaces exposed to water. The enhanced protection provided to microbial cells by the exopolysaccharides (EPS) brings added concerns about the possibility of H. pylori being transmitted through drinking water. H. pylori EPS as been reported to be composed mainly by Gal:Glc:GlcN in a proportion of 1.0:2.1:7.0, respectively (Stark et al., 1999). The present work brings about microscopical evidences of the capability of H. pilory to form free swimming bacterial aggregates and biofilms when submitted to nutrient depletion and hydrodynamic stress. Evidences that H. pylori aggregation is an exopolysaccharidic mediated phenomena both in planktonic and sessile states are also showed. Ethanol fractioning of the material recovered from these aggregates revealed an EPS composed of Gal:Glc:GlcN in a proportion of 1.0:0.4:1.6 respectively. A further structural detail about this EPS is under progress.

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Neste trabalho estudaram-se as alterações da microestrutura, textura e polissacarídeos da parede celular durante a confitagem da Ameixa dlElvas. Foram utilizadas ameixas não processadas ("Rainha Claudia Verde"), cozidas e confitadas. As células do parênquima das ameixas cozidas e as das confitadas, quando comparadas com as do fruto não processado, apresentaram degradação da parede celular primária, aumento do espaço intercelular e ruptura da estrutura do xilema. Nos ensaios de perfuração da polpa verificou-se uma diminuição na consistência do fruto após a fervura e um aumento na consistência do produto confitado para valores semelhantes aos obtidos para a polpa da ameixa não processada. Nas ameixas cozidas e nas confitadas, os polissacarídeos pécticos encontram-se degradados e solubilizados ao nível da lamela média e da parede celular primária, sendo esta solubilização mais evidente no produto final. Os resultados obtidos sugerem que a consistência do produto final é recuperada pela retenção de água pela sacarose nos tecidos e pela gelificação dos polissacarídeos pécticos modificados pelo cozimento do fruto.

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We present results on radiocarbon dating of foraminifera shell samples, collected on the upper slope of Campos Basin, in Southern Brazil. This is the first time that the sedimentation rate of this area is measured with a fine scale (cm) stratigraphy. C-14 ages vary from (2560 +/- 80) years. BP at the top to (7260 +/- 80) years. BP at the bottom of the sediment column. The mean accumulation ratio for the whole column is (6.2 +/- 0.7) cm/kyears. (C) 2004 Elsevier B.V. All rights reserved.

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