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- Morphological and mechanical characterization of films incorporating Porphyran extracted from Porphyra dioicaPublication . Baptista, Ricardo S.; Teles, Marco; Adão, Pedro; Afonso, Clélia; Bernardino, Raul; Bernardino, Susana; Ferro, Alberto C.; Elias, Sara; Guedes, MafaldaThis paper studies the effects of glycerol plasticizers and/or alginate, pectin, and carboxymethylcellulose polysaccharides on the mechanical and physical properties of porphyran-based films to evaluate the films’ ability to be used as food packaging. Films were characterized in terms of their composition, microstructural and morphological features, thermal properties, water interaction, and mechanical performance. All films are homogeneous, transparent, and slightly brownish in color. The structures are amorphous and crosslinked, showing the films’ thermoset nature. Moisture content and water solubility depend on the second polysaccharide added to the porphyran, but they both increase with the addition of glycerol to the formulations; water vapor permeability is strongly affected by the second polysaccharide in the formulation. The films display stiff and brittle mechanical behavior, but ductility increases significantly in formulations containing glycerol plasticizers. The barrier and mechanical performance values of the materials produced were found to be lower than those reported for commercial food packaging. The formulations containing glycerol displayed lower water vapor permeability values, ranging from 2.98 for porphyran/carboxymethylcellulose/glycerol to 6.65 mm.g.d-1.m-2.kPa-1 for porphyran/alginate/glycerol films. All films, except porphyran/glycerol and porphyran/alginate/glycerol, had ultimate tensile strengths above 10 MPa—the threshold value that ensures that a package is ductile enough to withstand handling and forming operations. Furthermore, the porphyran/ pectin/glycerol and porphyran/carboxymethylcellulose/glycerol films displayed sufficiently high ductility values of 2.94 and 3.10%, respectively. These results indicate that the studied porphyran/pectin/glycerol and porphyran/carboxymethylcellulose/glycerol formulations have a combination of physical and mechanical properties that ensure adequate film integrity and function through the complete food packaging supply chain. The results here reported represent an opportunity to extend the scope of porphyran films to applications in the dry food packaging industry.
- Synthesis, binding properties and theoretical studies of p-tert-butylhexahomotrioxacalix[3]arene tri(adamantyl)ketone with alkali, alkaline earth, transition, heavy metal and lanthanide cationsPublication . Marcos, Paula M.; Ascenso, José R.; Segurado, Manuel A.P.; Bernardino, Raul J.; Cragg, Peter J.; Bernardino, Raulp-tert-Butylhexahomotrioxacalix[3]arene tri(adamantyl)ketone (1b) was synthesized for the first time. Compound 1b was obtained in a cone conformation in solution at room temperature, as established by NMR spectroscopy (1H and 13C). The binding properties of ligand 1b for alkali, alkaline earth, transition, heavy metal and lanthanide cations have been assessed by phase transfer and proton NMR titration experiments. Molecular mechanics and ab initio techniques were also employed to complement the NMR data. The results are compared to those obtained with other closely related homooxacalixarene derivatives. Although triketone 1b is a weak extractant, it shows a strong peak selectivity for Na+ and also some preference for Ag+. Proton NMR titrations indicate the formation of 1:1 complexes between 1b and the cations studied, and also that they should be located inside the cavity defined by the phenoxy and carbonyl oxygen atoms. Although the molecular mechanics results show little correlation with the NMR data, a good agreement was obtained with the ab initio models.
- Marine-Derived Polysaccharides and Their Potential Health Benefits in Nutraceutical ApplicationsPublication . Carrasqueira, Joana; Bernardino, Susana; Bernardino, Raul; Afonso, CléliaMarine-derived polysaccharides have sparked immense interest in the nutraceutical industry as they possess a wide range of bioactivities which are highlighted in this review. These include antioxidants, anti-inflammatory, anti-cancer, gut microbiota regulator, anti-diabetic, and anti-obesity. Algae, marine invertebrates, vertebrates, and microorganisms are the main sources of marine polysaccharides, such as alginate, fucoidan, laminarin, carrageenan, chitosan, glycosaminoglycans, and exopolysaccharides. The structure and functional groups of these compounds influence their bioactive properties. Moreover, the functional properties of polysaccharides, such as gelling, thickening, and stabilising capabilities, are also crucial in product development, where they can serve as gluten substitutes in bakery goods and stabilisers in icings, sauces, and yoghurts. The potential of commercial products under development, such as marine polysaccharide supplements, is discussed, along with already commercialised products in the nutraceutical market. This review emphasises the enormous potential of marine-derived polysaccharides as bioactive compounds with health benefits and commercial value.
- Development and characterization of flms for food application incorporating Porphyran extracted from Porphyra dioicaPublication . Teles, Marco; Adão, Pedro; Afonso, Clélia; Bernardino, Raul; Guedes, Mafalda; Baptista, Ricardo; Bernardino, SusanaNon-biodegradable plastic is one of the biggest environmental problems of our lifetime and, considering the present societal needs, it will get worse. Consequently, there is an urgent need to develop sustainable and renewable alternatives to plastic, such as plastic-like materials obtained from biodegradable polymers, namely sulfated polysaccharides, considered one of the most viable alternatives. There is also a need to obtain these materials in an environmentally and economically sustainable way. The hereby developed process of obtaining film-forming solutions from semi-refined porphyran (PorphSR) uses a green solvent (hot water) with a high extraction yield of semi-refined porphyran (26.66 +- 0.27%) in a reproducible way and with low levels of contaminants. The obtained semi-refined porphyran showed good antioxidant potential in all tests performed: HPSA (D0.066 +- 0.002), DPPH (2.23 +- 0.78%), FRAP (0.420 +- 0.014 eq. ascorbic acid ug mg-1 of extract) and ABTS (20.46 +- 0.90%). After being cast into films, the most notable antioxidant properties were those of the semi-refined porphyran in the DPPH, FRAP and ABTS assays and of the pectin, (PorphSR_PcT and PorphSR_PcT_Gly) in the HPSA assay. Morphologically, the films showed relatively homogeneous and low roughness surfaces. It is concluded that the described method to obtain semi-refined porphyran is feasible and reproducible, and that the developed films, mainly PorfP2_PcT_Gly, proved to be a potential candidate for non-biodegradable plastic substitutes.
- Caraterização de Sistema Hidropónico de Tomateiro - Comparação com Sistema de AquaponiaPublication . Ferreira, S.; Bernardino, R.A preocupação com a gestão da água assume-se no século XXI como um dos mais importantes temas de sustentabilidade do nosso planeta. A FAO (Organização das Nações Unidas para Agricultura e Alimentação) apresentou os grandes objetivos para o desenvolvimento sustentável até 2030, onde o 6.º objetivo tem como um dos alvos melhorar a qualidade da água, reduzindo a poluição, eliminando o despejo e minimizando a libertação de produtos químicos e materiais perigosos, reduzindo para metade a proporção de águas residuais não tratadas e aumentando substancialmente a reciclagem e a reutilização segura em todo o mundo. A hidroponia apresenta-se, atualmente, como o processo produtivo de hortícolas que permite rentabilizar a produção aliada ao controlo de soluções nutritivas e consumo de água. Existe também um sistema de produção com base na utilização de água como transportador de nutrientes para as plantas, mas obtendo nutrientes através do ciclo do azoto, utilizando a Aquacultura e filtros biológicos que fornecem água rica em nutrientes, chamando-se este sistema de aquaponia. Este último, apresenta-se como o sistema de maior sustentabilidade de produção de hortícolas. Neste sentido procurouse com este trabalho, para além de caracterizar um sistema de produção de tomate em hidroponia, identificar o consumo de água e respetivo desaproveitamento, através da medição da quantidade da água de rega e água de drenagem, permitindo obter a percentagem de drenagem. Por outro lado, pretendeu-se perceber qual o nível de desperdício de nutrientes existente neste processo, efetuando o controlo de pH e Condutividade Elétrica da água de Rega e da água de Drenagem. Em paralelo ao controlo do sistema de hidroponia, realizou-se um ensaio num sistema piloto de aquaponia. Foi realizada a produção de tomate de cacho durante uma campanha, com a variedade Bigram SW enxertada (Porta Enxerto Beaufort F1), em ambos os sistemas, onde se fizeram comparações da produção e da qualidade do fruto. No sistema de hidroponia a Condutividade Elétrica utilizada na água de rega foi de 2.7 mS/cm2 e no sistema de aquaponia a Condutividade Elétrica inicia foi de 1.4 mS/cm2. Obtiveram-se os seguintes resultados: em hidroponia produziu-se 4.32 kg/tomateiro e em aquaponia 4.64 kg/tomateiro; o fruto na hidroponia obteve entre 4.6 e 5.1 ºbrix e um calibre constante de 67 mm, na aquaponia o fruto obteve entre 3.7 e 4.5 ºbrix e um calibre entre os 67 e os 82 mm. Podemos concluir que o sistema de hidroponia apresenta-se estável relativamente à obtenção de um produto homogéneo e de qualidade, mas que o sistema de Aquaponia pode ser o grande um meio para atingir o objetivo de produzir de um modo mais sustentável, utilizando uma quantidade de água muito inferior à hidroponia, bem como a não necessidade de adição de adubos às soluções nutritivas, se forem utilizadas densidades de peixes adequadas. É ainda possível melhorar o processo de hidroponia, aplicando o reaproveitamento de águas de drenagem e alterando a monitorização das águas de rega e drenagem para obtenção regular de concentrações de nutrientes, de modo a ajustar a adição de adubos conforme a necessidade das plantas.
- Development and characterization of films for food application incorporating porphyran extracted from Porphyra dioicaPublication . Teles, Marco; Adão, Pedro; Afonso, Clélia; Bernardino, Raul; Guedes, Mafalda; Baptista, Ricardo; Bernardino, SusanaNon-biodegradable plastic is one of the biggest environmental problems of our lifetime and, considering the present societal needs, it will get worse. Consequently, there is an urgent need to develop sustainable and renewable alternatives to plastic, such as plastic-like materials obtained from biodegradable polymers, namely sulfated polysaccharides, considered one of the most viable alternatives. There is also a need to obtain these materials in an environmentally and economically sustainable way. The hereby developed process of obtaining film-forming solutions from semi-refined porphyran (PorphSR) uses a green solvent (hot water) with a high extraction yield of semi-refined porphyran (26.66 +- 0.27%) in a reproducible way and with low levels of contaminants. The obtained semi-refined porphyran showed good antioxidant potential in all tests performed: HPSA (D0.066 +- 0.002), DPPH (2.23 +- 0.78%), FRAP (0.420 +- 0.014 eq. ascorbic acid ug mg-1 of extract) and ABTS (20.46 0.90%). After being cast into films, the most notable antioxidant properties were those of the semi-refined porphyran in the DPPH, FRAP and ABTS assays and of the pectin, (PorphSR_PcT and PorphSR_PcT_Gly) in the HPSA assay. Morphologically, the films showed relatively homogeneous and low roughness surfaces. It is concluded that the described method to obtain semi-refined porphyran is feasible and reproducible, and that the developed films, mainly PorfP2_PcT_Gly, proved to be a potential candidate for non-biodegradable plastic substitutes.
- Nutrient‐efficient catfish‐based aquaponics for producing lamb's lettuce at two light intensitiesPublication . Sebastião, Fernando; Vaz, Daniela C.; Pires, Cristiana L; Cruz, Pedro F; Moreno, Maria João; Brito, Rui M M; Cotrim, Luís; Oliveira, Nelson; Costa, Ana; Fonseca, André; Rodrigues, Maria; Ispolnov, Kirill; Bernardino, Raul; Vieira, JuditeBACKGROUND: Aquaponic systems are sustainable processes of managing water and nutrients for food production. An innovate nutrient-efficient catfish-based (Clarias gariepinus) aquaponics system was implemented for producing two cultivars of two leafy vegetables largely consumed worldwide: lamb's lettuce (Valerianella locusta var. Favor and Valerianella locusta var. de Hollande) and arugula (Eruca vesicaria var. sativa and Eruca sativa). Different growing treatments (4 × 2 factorial design) were applied to plants of each cultivar, grown at two light intensities (120 and 400 ∼mol m−2 s −1). During growth, several morphological characteristics (root length, plant height, leaf number, foliage diameter and biggest leaf length) were measured. At harvest, plants were weighed and examined qualitatively in terms of greenness and health status. Additionally, leaf extracts were obtained and used to determine total phenolic contents, antioxidant capacities, and levels of cytotoxicity to Caco-2 intestinal model cells. RESULTS: After a 5-week growth period, both lamb's lettuce cultivars presented high levels of greenness and health status, at both light intensities, particularly the var. de Hollande that also showed higher average performance in terms of plant morphology. In turn, arugula cultivars showed lower levels of greenness and health status, especially the cultivar E. vesicaria var. sativa submitted to direct sunlight during growth. In addition, plant specimens submitted to higher levels of light intensity showed higher contents in antioxidants/polyphenols. Cultivars with a higher content in antioxidants/polyphenols led to higher Caco-2 cell viability. CONCLUSION: For successful industrial implementation of the aquaponics technology, different and optimized acclimatizing conditions must be applied to different plant species and cultivars. © 2024 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
- Adding value to stalked barnacles from Berlengas Nature Reserve (Portugal) by the development of a new foodPublication . Pinheiro, Joaquina; Fernandes, Wilson; Sá, Hugo; Bernardino, Raul; Leandro, Sérgio Miguel; Ganhão, RuiIn this work, a new and natural food product, stalked barnacle (Pollicipes Pollicipes) pâté enriched with blackberry, was developed to valorise the rejected stalked barnacle. To evaluate the addition of blackberry fruits (Rubus ulmifolius Schott.) as a natural preservative on pâté quality, four pâté sample groups were considered: a negative control without a synthetic additive (CTR), a positive control with butylated hydroxytoluene (BHT), a group with blackberry extract (blackberry), and a group with a mixture of BHT and blackberry (blackberry + BHT). In addition, the effect of pasteurization (80 °C for 30 min) versus sterilization (121 °C for 30 min) on the pâté quality were evaluated. The bioactive evaluation expressed by the total phenolic content (TPC) and antiradical activity by the DPPH radical scavenging associated with oxidative stability determined by thiobarbituric acid reacting substances (TBARS) were performed. The impact of packaging opening followed by refrigerated storage (4 ± 1 °C) simulating the consumer behavior at home, was assessed. All the heat-treated stalked barnacle pâté samples were found microbially safe with an interesting content of total phenolic, the highest ones being the CTR and Blackberry + BHT, ranging from 58.79 to 55.38 mg GAE/100 g. After the package opening of the barnacle pâté sample of Blackberry + BHT, it revealed a superior inhibition of TBARS (0.46 mg MDA/100 g) after 7 days at refrigerated storage compared to the other samples. These results state the efficacy of blackberry in minimizing the lipid oxidation of stalked barnacle pâte. This study showed the potential for rejected stalked barnacle to be valorised and improve the sustainability of resources.
- Homegreens - Aquaponics System as an Educational Tool towards a Sustainable FuturePublication . Carreira, Rute; Diz, Francisco; Pessanha, Luis; Bernardino, Raul; Franco, Inês M.; Mota, Alexandra; Faustino, Emanuel; Silva, Orlando R.; Ferreira, Susana M. F.Aquaponics is an integrated production practice that emerges from the combi-nation of two farming techniques: hydroponics and aquaculture. It consists in a simulation of a natural ecosystem that grows plants without soil substrate in the nutrient enriched waters recirculated from aquaculture systems. This type of production offers several advantages, namely economic and ecological ones. Homegreens is a project that aims to create small saltwater and freshwater aquaponic sys-tems, which can be installed in schools and serve as a didactic tool for introducing contents such as biology and sustainability to a juvenile audience. Implemented by a designers, biol-ogists and agronomists’ multidisciplinary team, the methodology was based on the develop-ment and quantitative validation of prototypes, and the installation and qualitative analyses of user’s interaction. These small scale aquaponic systems consists on a grow bed, an aquarium with a capacity for 45L, a protection barrier for the plant’s roots, aeration, biofilters and a thermostat. Sever-al simplified models were developed, presented and installed in two primary schools. Labor-atory tests were conducted to validate the use of a cork grow bed and a 3D printed polya-cid lactic (PLA) aeration and biofilter system. Children’s engagement and interaction with these simplified models, indicates that these systems will provide a biology and sustainability related group learning opportunity.
- Bioremediation of Synthetic Wastewater with Contaminants of Emerging Concern by Nannochloropsis sp. and Lipid Production: A Circular ApproachPublication . Santos, Bruna; Araújo, Juliana; Carvalho, Beatriz; Cotrim, Carolina; Bernardino, Raul; Freitas, Filomena; Sobral, Abílio J. F. N.; Encarnação, TelmaContaminants of emerging concern (CECs) pose a potential risk to human and environmental health. Microalgae bioremediation is a promising approach for transforming or removing contaminants from the environment, while contributing to the circular economy. In this study, Nannochloropsis sp. was effectively used for the simultaneous removal of six CECs: paracetamol, ibuprofen, imidacloprid, methylparaben and bisphenol A at 10 µg mL−1 and triclosan at 0.5 µg mL−1 from synthetic wastewater, which were able to survive under such concentrations, higher than those commonly found in the environment (up to 2.82 µg mL−1 of methylparaben). High removal efficiencies were reached for methylparaben (100%) and bisphenol A (93 ± 2%), while for imidacloprid, paracetamol and ibuprofen, 30 ± 1%, 64 ± 2% and 49 ± 5% were removed, respectively. Subsequently, lipids were extracted, and the FAME profile was characterised using GS-MS. The main fatty acids identified after bioremediation were hexadecadienoic acid isomers (C16:2), palmitic acid (C16), linoleic acid (C18:2) and γ-linolenic acid (C18:3). The absence of oleic acid and stearic acid was noticed, suggesting an alteration in the lipidic profile due to contaminant exposure. By exploring the quantification of fatty acids in future work, potential applications for the extracted lipids can be explored, further demonstrating the feasibility of this circular process.