CBQF - Documentos de Conferências / Conference Objects
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- BioUpCycle: circular innovation for the bioeconomy through the upcycling of agro-residuesPublication . Vilas-Boas, Ana Martins; Sousa, Ana Sofia; Magalhães, Daniela; Coelho, Marta; Cunha, Marta Fernandez; Pintado, Manuela
- Valorization of xylo-oligosaccharides from brewer’s spent grain: antioxidant, antimicrobial and glycemic modulation potentialPublication . Anthero, Ana Gabriela da Silva; Castilho, Pamela Alves; Silva, Sara; Costa, Eduardo; Rodrigues, Antonio Augusto; de Sá-Nakanishi, Anacharis Babeto; Pintado, Manuela; Goldbeck, RosanaBrewer’s spent grain (BSG), the main by-product of the brewing industry, is an abundant lignocellulosic material with potential for the production of value-added functional ingredients. The recovery of xylo-oligosaccharides (XOS) from BSG represents a sustainable strategy for by-product valorization, as these compounds are associated with prebiotic and health-promoting properties. In this context, the study aimed to produce, purify, characterize, and evaluate the functional properties of XOS obtained from BSG, including antioxidant, antimicrobial, and glycemic modulation potential. XOS were produced through alkaline extraction followed by enzymatic hydrolysis of the hemicellulosic fraction. After production, the XOS fraction was purified and concentrated, and the oligosaccharide profile was characterized by ion-exchange chromatography. Phenolic compounds content and antioxidant activity were evaluated before and after simulated gastrointestinal digestion using Folin–Ciocalteu and ABTS assays, respectively. Antimicrobial activity was determined by the minimum inhibitory concentration (MIC) method against foodborne pathogens, including Gram-positive (Staphylococcus aureus, Bacillus cereus, and Listeria monocytogenes) and Gram-negative (Salmonella enterica and Escherichia coli) strains. The potential for glycemic modulation was evaluated in vivo using an oral starch tolerance test with purified XOS at 3 g/L. As a result, the XOS profile consisted mainly of low-degree-of-polymerization oligomers, with a predominance of xylobiose (X2), followed by X3–X6 fractions, indicating efficient enzymatic hydrolysis of xylan and the formation of soluble short-chain oligosaccharides with potential functional applications. Digested XOS exhibited enhanced antioxidant responses compared with non-digested samples, suggesting increased availability of bioactive compounds after gastrointestinal processing. Purified XOS showed antimicrobial activity against all tested microorganisms, with a MIC of 2 g/L. In the in vivo assay, XOS supplementation reduced postprandial glucose peaks compared with the starch control group. Overall, purified BSG-derived XOS demonstrated multifunctional properties, combining antioxidant capacity, antimicrobial activity, and potential for glycemic modulation. The predominance of short-chain XOS and their biological effects highlights the potential of brewer’s spent grain as a sustainable source of functional ingredients for innovative food applications.
- Characterization of microbial colonization of three mural painting’s churches (N. Portugal): preliminary study of microbial growth, biocides activity evaluation and future intervention proposalPublication . Marco, A.; Vieira, E.; Pintado, M.; Moreira, P. R.
- Extracellular ligninolytic enzyme activities in yeast isolates from wastewater treatment plantsPublication . Silva, A. R.; Moreira, P. R.; Pintado, M.Many microorganisms have been found to be capable of degrading dyes; these include bacteria, filamentous fungi, yeasts, actinomycetes and algae. When compared to bacteria and filamentous fungi, yeasts present advantages; they grow rapidly and have the ability to resist unfavourable conditions. However, degradation of synthetic dyes by yeasts has not been extensively reported, namely its relation with extracellular ligninolytic enzymes. Forty six yeast strains isolated from two wastewater treatment stations along with other 81 cheese isolates were compared on their ability to decolorize five textile dyes in solid media. After a screening methodology that included liquid culture decoulorisation ability evaluation, yeasts isolates, LIII S 36 and L III ST 7 presented the best performance in the decolourisation for the five dyes tested: Remazol Black B-A, Remazol Yellow RR, Levafix Blue CA, Remazol Brilliant Blue R and Levafix® Red CA). As an attempt to understand the mechanism of decolourisation of the strains, L III ST 7 and L III S 36, spectral scanning and enzymatic activity assays were performed. It was possible observe that, depending on the dye, decolourisation might be achieved through mechanisms of either adsorption or true degradation. The presence of extracellular ligninolytic manganese peroxidase activity was detected in strains L III ST 7 and L III S 36 with an average of 2.30 and 2.06 IU. l-1, respectively; this enzymatic activity rarely demonstrated in yeasts might be related to the mechanism of true degradation as already proven for several filamentous fungi.
- Effect of drying temperature on a plant-based egg analogue powder and its performance in cookies compared with commercial egg powderPublication . Farrokhi, Mahsa; Ceccarelli, Alessia; Gomes, Filipe Alberto; Romanetto, Valentina; Momodu, Falilat; Brandão, Teresa R. S.; Silva, Cristina L. M.The increasing demand for sustainable food ingredients has driven the development of plant-based alternatives to animal-derived products, particularly eggs, which provide multiple functional roles in bakery systems. This study aimed to develop a shelf-stable, plant-based egg analogue powder based on pea protein and cereal flours and to evaluate the effect of static oven drying temperature on its physicochemical stability and functional performance in cookies, compared with a commercial egg powder. A liquid egg analogue emulsion was prepared and dried in a static oven at 55 °C, 65 °C, or 70 °C until constant weight, followed by milling. Rehydrated powders were characterized for emulsion stability, color, pH, water activity, and soluble solids. Functional performance was evaluated by producing cookies in which the egg analogue powders were rehydrated and incorporated into the dough using identical formulations and processing conditions as those applied for commercial egg powder. Drying temperature did not significantly affect lightness (L*) or redness (a*), indicating good color stability, while minor variations in yellowness (b*) and pH were observed. Emulsion stability was strongly influenced by drying temperature. The analogue dried at 70 °C showed the highest total instability (22.2% after 60 min), primarily due to oil release, whereas samples dried at 55 °C and 65 °C exhibited greater suspension stability with limited oil separation (≈10% total instability). Sensory evaluation revealed an inverse relationship between emulsion stability and cookie quality. Cookies prepared with the 70 °C dried analogue achieved the highest sensory acceptance (“Excellent”), exhibiting a soft, pliable texture and pleasant mouthfeel comparable to those made with commercial egg powder. In contrast, cookies produced with analogues dried at lower temperatures were perceived as dry and floury. These findings indicate that a controlled degree of oil release upon rehydration is beneficial for mimicking the lubricating function of egg yolk lipids in cookies. In conclusion, static oven drying at 70 °C was identified as the most effective condition for producing a functional plant-based egg analogue powder capable of replacing commercial egg powder in cookie formulations, highlighting the importance of optimizing drying parameters to balance stability and end-use functionality.
- Linking bioaccessibility and carotenoids to antioxidant activity in diatomsPublication . Rocha, Helena R.; Coelho, Marta; Coelho, Natacha; Morais, Rui M. S. C.; Pintado, Manuela; Gomes, Ana M.Diatoms are photosynthetic microalgae with a siliceous cell wall and remarkable adaptability, making them a sustainable and renewable resource for high-value bioactive compounds (1,2). Their rapid growth, efficient carbon fixation, and minimal land and freshwater requirements (1,2) position them as attractive candidates for the development of eco-friendly products in the nutraceutical, pharmaceutical, and cosmetic industries. Among their most relevant metabolites are carotenoids and phenolic compounds, which exhibit strong antioxidant properties (3,4,5). This study explores the carotenoid profile of Chaetoceros calcitrans, Nannofrustulum shiloi, and Cylindrotheca fusiformis, and evaluates their antioxidant capacity using ABTS and DPPH assays. Furthermore, the natural bioaccessibility of carotenoids was assessed using the INFOGEST in vitro digestion model, highlighting the relevance of these compounds under physiological conditions and their potential for sustainable functional applications.
- Chemical and bioactive composition of mushroom biomass: understanding their nutritive and health valuePublication . Araújo-Rodrigues, Helena; Salsinha, Ana Sofia; Amorim, Manuela; Relvas, João B.; Tavaria, Freni Kekhasharú; Pintado, Manuela E.Beyond interesting nutritional properties, mushrooms possess numerous bioactive compounds involved in human health1. Distinct macromolecules are found in the mushroom mycelium and fruiting body. Mushroom biomass (MB) corresponds to the mycelium and young fruiting body (primordia). A synergetic effect between their different molecules has been proposed2. Additionally, the entire mushroom valorization may increase the economic value and minimize waste, contributing to a circular economy approach. To understand the MB nutritional value, the chemical and bioactive composition of three food and medicinal species was assessed for the first time, namely, Coriolus versicolor (CV), Hericium erinaceus (HE) and Pleurotus ostreatus (PO). The methodological approaches included: enzymatic kits for fiber and glucans quantification; inductively coupled plasma-optical emission spectrometry for mineral analysis; and gas-chromatography and high-performance liquid chromatography for other groups' quantification. No significant differences were found in total amino acids (AAs; 6.3-6.9%), α-glucans (71-78%) and β-glucans (3-5%) between species. Higher amounts of total (6.2%) and soluble proteins (2%), ash (1.5%), free sugars (1.2%) and free AAs (0.4%) were found in CV. Regarding HE composition, this had higher carbohydrates (93.1%), fat (1.8%), fiber (6.1%) and energy (382 kcal/ 100 g). The results of free and total AAs suggested that glutamic and aspartic acids, arginine, alanine and leucine were the most prevalent. Concerning mineral and fatty acid composition, the results indicated that the three species possessed very interesting profiles, being good sources of phosphorus, magnesium, calcium and potassium; and oleic, linoleic and α-linolenic acids. Moreover, a significant presence of other important bioactive groups that play important roles in human health was detected such as phenolics, carotenoids, and ergosterol in CV; and tocopherols in HE. The antioxidant capacity tests also suggested the high antioxidant potential of CV. These results demonstrated the high potential of these MBs to be used in human nutrition and health applications.
- Characterization of bioactive compounds in mushroom biomass from Coriolus versicolor, Hericium erinaceus and Pleurotus ostreatus speciesPublication . Araújo-Rodrigues, Helena; Amorim, Manuela; Salsinha, Ana Sofia; Marçal, Sara; Relvas, João B.; Tavaria, Freni Kekhasharú; Pintado, Manuela E.Recent research data have suggested the high therapeutical potential of gut microbiota modulation in numerous diseases. Nowadays, faecal transplantation, probiotics and prebiotics supplementation are strategies extensively used in the treatment of several disorders [1]. Prebiotic rich-foods play an important role in gut microbiota modulation. Beyond the rich nutritional value and various biological properties of mushrooms, several species have been described as prebiotics [2]. Prebiotics are defined as “a substrate that is selectively utilized by host microorganisms conferring a health benefit” [3]. Mushrooms also possess several health benefits such as antitumor, immunomodulatory, antioxidant and neuroprotective. This fact results in an increasing interest in identifying mushroom species and their bioactive molecules. Most research works focus on testing extracts or isolated compounds but a positive synergistic effect between molecules present in mushroom biomass has also been proposed [2]. In the present work, the mushroom biomass of Coriolus versicolor (CV), Hericium erinaceus (HE) and Pleurotus ostreatus (PO) species were chemically characterized and their main bioactive groups were identified and quantified towards the understanding of their biological potential.
- Breaking the ripening barrier in 'Rocha' pears treated with 1-MCP: the role of abscisic and glyoxylic acidsPublication . Dias, Cindy; Sousa, Clara; Vasconcelos, Marta W.; Ferrante, Antonio; Pintado, Manuela E.Extending the cold storage of 'Rocha' pears through 1-methylcyclopropene (1-MCP) and controlled atmosphere storage is a widely used strategy to prevent postharvest disorders. However, this approach inhibits natural fruit ripening, often compromising consumer quality and presenting a significant challenge to the fruit industry. Basically, 1-MCP binds to the ethylene recpetor proteins found in fruit, not allowing ethylene to bind, and triggering the ripening response. Recently, several studies, strategies to mitigate the antagonist ripening effect of 1-MCP have been attempted. In this study, we investigated the potential of abscisic acid (ABA) and glyoxylic acid (GLA) to counteract the antagonist effects of 1-MCP and restore normal ripening. 'Rocha' pears treated with 1-MCP were immersed in ABA or GLA solutions, respectively, and stored at 20 ± 2 °C for 15 days. Ripening indicators, including firmness, skin color, ethylene and volatile organic compound (VOC) production, sugar content, and the expression of ethylene-related genes (PcACS, PcACO, PcETR1, PcETR2, and PcETR5), were assessed throughout storage. Our multivariate and clustering analysis revealed that ABA effectively disrupted the 1-MCP-induced ripening inhibition, significantly boosting ethylene production and, consequently, promoting fruit softening, degreening, sugar accumulation, and specific pear-ripening volatile emissions. These changes were justified by the significant measured increased expression of ethylene biosynthesis (PcACS, PcACO) and receptor (PcETR2) genes, highlighting ABA’s pivotal role in reactivating ethylene perception, signaling, metabolism and, therefore, the ripening process. In contrast, GLA did not promote an increase in ethylene production or other ripening-related changes, likely due to limited ACC synthase activity. Interestingly, GLA-treated fruits showed elevated respiration rates and higher levels of hexanal, (E)-2-hexenal, and ethanol compared to the control, indicating an influence on alternative stressed metabolic pathways unrelated to ripening. This study sheds light on the regulatory interplay between ABA, GLA, and fruit ripening, providing innovative strategies to overcome ripening inhibition caused by 1-MCP in climacteric fruits, with particular focus on ‘Rocha’ pear.
- Productive potential of floating wetland islands for sustainable agriculturePublication . Carrillo, Valentina; Calheiros, Cristina S. C.; Pereira, SofiaFloating wetland islands (FWIs) are artificial platforms designed to float on water bodies while supporting plant growth, representing a promising integration of ecological engineering and crop production. Originally developed for water quality improvement, FWIs have evolved into multifunctional systems capable of cultivating edible crops, such as lettuce, spinach, and rice, within nutrient-rich aquatic environments. Their dual role in environmental remediation and food production positions FWIs as innovative nature-based solutions (NbSs) aligned with sustainable development goals. This study identifies and discusses the key components, challenges and future opportunities for the application of FWIs in agricultural contexts. Design parameters, such as crop selection, substrate type and platform buoyancy, play a crucial role in system stability and productivity. Operational aspects, such as maintenance, cost-effectiveness and social acceptance, determine the feasibility of large-scale application. From an agronomic point of view, FWIs enable biomass production, nutrient uptake and safe food cultivation, although potential toxicity must be taken into account. Beyond agriculture, FWIs contribute to water treatment through nutrient removal, pollutant reduction and water reuse, reinforcing their role as low-impact, decentralized systems for polluted water bodies. They also offer important environmental benefits, such as carbon sequestration, nutrient cycling and improved landscape aesthetics. Looking ahead, FWIs present great potential for integration into the circular economy, technological innovation and climate adaptation strategies, especially in regions facing water scarcity, land degradation or urban sprawl. Their multifunctionality and adaptability highlight that FWIs are resilient systems that link food production with environmental sustainability. This study contributes to the growing knowledge gap on FWIs and supports their application as sustainable alternatives for integrated agriculture and water management.