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- Exploring persistence markers through fatty acid profiles of listeria monocytogenes under distinct temperature conditionsPublication . Magalhães, Rui; Machado, Manuela; Teixeira, PaulaIntroduction: Listeria monocytogenes, the causative agent of listeriosis, is a major foodborne pathogen. It is a ubiquitous, facultative anaerobic, gram-positive bacterium. Listeriosis can be a severe illness particularly affecting vulnerable groups: the elderly, immunocompromised individuals, pregnant women and neonates. Listeria monocytogenes exhibits remarkable adaptability to diverse and challenging environments, demonstrating an exceptional capacity to thrive in conditions such as refrigeration temperatures or high salt concentrations or other factors found in food processing environments (FPE). This resilience is a key factor in its ability to persist within food processing facilities and proliferate in various food products. Only certain strains are routinely isolated from these FPEs (persistent strains) while others are isolated sporadically (non-persistent strains). Objectives: This study aimed to identify fatty acids that could serve as persistence markers in isolates from the GenoPhenoTraits4Persistence collection, classified as persistent (P) or non- persistent (NP). Conclusions: Fatty acid profiles at 10 ?C demonstrate clear clustering according to clonal complex, indicating that membrane lipid composition is predominantly influenced by genetic lineage. Variations in persistence status do not account for differences in lipid profiles, implying that persistence in food-processing environments is governed by factors beyond membrane fatty acid composition. The detection of branched-chain fatty acids iso-C15 and iso-C17, along with ?C19 at low temperatures, underscores their significance in L. monocytogenes adaptation to environmental stresses, particularly temperature changes and membrane fluidity regulation. Principal component analysis (PCA) confirmed strong clustering of fatty acid profiles by clonal complex, reinforcing the role of genetic background in shaping membrane lipid composition. Persistence status failed to explain the variability observed, suggesting that survival in food-processing settings depends on mechanisms other than fatty acid makeup. These lipid markers will be further investigated to determine their potential role in the adaptation and resilience of these strains under challenging conditions.
- Alkaline extraction of phenolic compounds from Eucalyptus leaves: influence on antioxidant and antimicrobial activityPublication . Afonso, Tiago Barros; Bonifácio-Lopes, Teresa; Costa, Eduardo; Macedo, Tiago; Moreira, Joana; Oliveira, Juliana; Pintado, ManuelaBackground: The valorization of agro-industrial by-products is a strategic approach to reducing biomass waste while advancing circular bioeconomy practices. Eucalyptus leaves, an abundant residue from the forestry and pulp industries, are particularly rich in phenolic compounds with well- known antioxidant and antimicrobial activities. These bioactivities highlight the potential of eucalyptus extracts for sustainable applications in the cosmetic and textile industries. However, their efficient recovery requires optimized extraction methodologies capable of disrupting the complex plant matrix and maximizing compound release. In this work, we explored alkaline extraction, focusing on the influence of particle size and alkali concentration on the recovery of phenolic-rich extracts with bioactive potential. Methods: Eucalyptus leaves were processed at two particle sizes (4 mm and 10 mm) and extracted using NaOH at two concentrations (0.1 M and 0.3 M). Extracts were analyzed for total phenolic and flavonoid content as well as antioxidant capacity using ORAC assay. Phenolic composition was characterized by LC-ESI-QqTOF-HRMS. Furthermore, the antimicrobial efficacy of the extracts was tested against different Gram-negative and Gram-positive bacteria as well as the yeast Malassezia furfur. Additionally, the biocompatibility of the extracts was evaluated on a human keratinocyte cell line (HaCaT). Results: Smaller particle sizes (4 mm) combined with lower NaOH concentrations (0.1 M) yielded extracts with higher total phenolic and flavonoid content. In terms of antioxidant activity, no significant differences were observed between the different extracts. LC-ESI-QqTOF-HRMS analysis revealed the presence of phenolic acids (e.g., quinic and gallic acid) and flavonoids (e.g., quercetin-3-O-glucuronide) with compositional differences across conditions. All extracts displayed strong antimicrobial activity against Gram-positive bacteria and M. furfur, with MIC values below 1.25 mg/mL in most cases. However, cytotoxicity assays indicated reduced HaCaT viability at concentrations ? 500 ?g/mL. Conclusions: Alkaline extraction proved effective for recovering phenolic compounds from eucalyptus leaves, yielding extracts with strong antioxidant and antimicrobial activities. These findings support their potential for skin-related applications, including cosmetics and functional textiles, although further optimization of extraction conditions and safety thresholds is required.
- Interações gene-ambiente envolvendo genes de metabolismo de xenobióticos e risco de HNSCC : uma revisão sistemáticaPublication . Monteiro, Mateus Luís; Santos, Luís Filipe de Sepúlveda Silva; Silva, Raquel Monteiro Marques daIntrodução e objetivo: O carcinoma de células escamosas da cabeça e pescoço (HNSCC) é o sexto cancro mais prevalente mundialmente. Esta revisão sistemática teve como objetivo avaliar a evidência existente sobre as interações entre polimorfismos genéticos (SNPs) em genes de metabolismo de xenobióticos e fatores ambientais, bem como o papel dessas interações na suscetibilidade individual ao HNSCC. Materiais e Métodos: A prossecução desta revisão sistemática compreendeu a realização de uma busca nas bases de dados PubMed, Scopus e Web of Science, combinando termos MeSH e linguagem corrente. Incluíram-se estudos caso-controlo que analisaram interações entre SNPs em genes de metabolismo de xenobióticos e fatores ambientais associados ao risco de HNSCC. A revisão foi conduzida de acordo com os critérios PICO e as diretrizes PRISMA e registadas na base de dados PROSPERO (ID: 1076564). Os programas Rayyan e Excel foram utilizados para a extração e análise dos dados, respetivamente. Resultados: Dos 27 estudos incluídos (275 interações GxE), 138 apresentaram resultados estatisticamente significativos. As interações mais significativas envolveram genes da família CYP, outros genes de fase I e genes da família GST. Entre os fatores ambientais, destacaram-se o consumo de álcool, tabaco e o hábito de mascar tabaco. Os genes CYP1A1, CYP1B1 e CYP2E1 interagiram significativamente com os três consumos, enquanto GSTM1 e GSTT1 mostraram associações com álcool e mascar tabaco. Já GSTM1, GSTP1 e GSTT1 apresentaram interações relevantes com o tabaco. Entre os genes de fase I, ALDH1B, ADH1C e ALDH2 associaram-se particularmente ao consumo de álcool. Conclusão: A presença de SNPs em genes das famílias CYP e GST, entre outros, interage com o consumo de álcool, tabaco bem como o hábito de mascar tabaco, com impacto no risco de HNSCC. Estudos futuros com amostras maiores e populações diversificadas são necessários para confirmar estas associações e clarificar o seu impacto clínico.
- Playing solo, against rivals, or in a team? Exploring individual, competitive, and cooperative dynamics in gamified digital educationPublication . Coelho, Franz; Rando, Belén; Bernardes, Rafael; Pontífice-Sousa, Patrícia; Gonçalves, Daniel; Abreu, Ana MariaWhile gamification is increasingly applied in education, research rarely compares distinct social dynamics and evaluates their cognitive, emotional, and motivational impact in a learning context. This study examines the effects of social gamification in education using a digital learning platform and a randomized controlled trial (RCT). Following research standards (CONSORT, Cochrane Collaboration, EVAT©), we compared individual, competitive, and cooperative gamification modes to assess the impact of social dynamics on nursing undergraduate students (n?=?42). We analyzed participant characteristics (sociodemographics, gaming habits, player traits) alongside cognitive (learning, engagement, eye-tracking visual attention), emotional (facial emotion recognition), and motivational (intrinsic motivation) outcomes. Participants in the individual mode showed significantly higher eye-tracking visual attention than those in competition or cooperation modes. Social gamification appeared to reduce attention, likely due to cognitive overload from digital multitasking and distractions. Given the rise of the attention economy, individual gamified sessions may better sustain focus, aligning with trends toward personalized digital learning. Digital social gamification may not mirror the benefits of in-person interaction. The absence of significant differences in outcomes beyond visual attention may stem from contextual factors—such as weak social traits, low gaming interest, and health-related backgrounds—suggesting effective gamified strategies must align with learner profiles and context.
- Fostering school belonging among Portuguese adolescents: psychosocial predictors and guidelines for educational actionPublication . Reis, Marta; Noronha, Catarina; Tomé, Gina; Carvalho, Marina; Rodrigues, Nuno Neto; Matos, Margarida Gaspar deIntroduction: School belonging is a key component of adolescent well-being, associated with academic success, mental health, and social inclusion. This study explores the levels of school belonging among Portuguese students and examines the psychosocial factors associated with this perception. Methods: Data from 3083 students (5th to 12th grade) obtained through the 2024 National Study by the Observatory of Psychological Health and Well-Being were analysed. Socio-emotional skills, well-being indicators, psychological symptoms, and school engagement variables were assessed using validated instruments. Statistical analyses included ANOVA and linear regression. Results: Overall, boys and younger students reported higher levels of school belonging. Sociability, resilience, confidence, school engagement, and and components of Positive Youth Development (PYD)—a strengths-based framework focusing on the internal and external assets that foster healthy youth development—such as competence and connection, were positively associated with school belonging. Conversely, depressive symptoms and experiences of bullying negatively predicted this outcome. Conclusions: This study’s findings highlight the need to reinforce inclusive educational practices, foster positive youth development, and promote protective relational dynamics within the school context.
- Integrating traditional antifungal tests and flow cytometry to evaluate the activity of essential oils against malassezia furfurPublication . Lopes, Ana I.; Oliveira, Cláudia S.; Pintado, Manuela E.; Tavaria, Freni K.Background: Malassezia spp. are lipid-dependent yeasts that are an important part of the normal skin mycobiome in humans and other warm-blooded animals. Although generally harmless, they can, under certain conditions, contribute to skin disorders, with Malassezia furfur (M. furfur) being the main species linked to invasive infections. Current treatment mainly relies on topical or systemic antifungals, which, despite their effectiveness, are limited by side effects, drug interactions, species- specific resistance, and frequent recurrences. In this context, essential oils (EOs) are emerging as promising alternatives, as they show broad-spectrum antimicrobial activity and multi-target mechanisms that lower the risk of resistance. Thus, this study aimed to evaluate the antifungal activity of six EOs—rosemary, eucalyptus, lavender, basil, sage, and thyme—against M. furfur. Methods: Antifungal activity was assessed through: (i) agar diffusion assay; (ii) determination of minimum inhibitory (MIC) and fungicidal concentrations (MFC); (iii) growth inhibition curves at MIC; (iv) anti-biofilm activity at MIC, ½MIC, and ¼MIC; (v) membrane integrity analysis by flow cytometry using propidium iodide (PI) and thiazole orange (TO) for the most active oils (eucalyptus, lavender, thyme); and (vi) fluorescence microscopy of yeasts exposed to eucalyptus EO at ¼MIC. Results: Inhibition zones ranged from 20 ± 0.00 mm (rosemary) to 33 ± 2.00 mm (eucalyptus), with basil and thyme achieving complete inhibition. MIC and MFC values ranged from 0.08% to 2.5% (v/v), with thyme showing the lowest values. Growth inhibition curves confirmed MIC data. Thyme also displayed the strongest antibiofilm effect. Flow cytometry suggested the absence of viable cells due to a lack of TO staining, even in untreated controls. However, fluorescence microscopy revealed that cells remained viable but failed to show TO uptake, likely because the lipid-rich membrane interfered with staining. Conclusions: This work demonstrates the strong antifungal activity of EOs, particularly thyme, eucalyptus, and lavender, against M. furfur, affecting both planktonic and biofilm forms. Importantly, it represents one of the few studies applying flow cytometry to this yeast, exposing critical limitations in conventional staining methods. The novelty of this study advances knowledge on EO efficacy and highlights the need for further research to refine flow cytometry protocols for reliable assessment of M. furfur viability.
- Impacto das dinâmicas de grupo como recurso pedagógico na lecionação : unidade letiva: as origens do 7º ano de escolaridade de EMRCPublication . Soares, João Pedro Azevedo; Moreira, Carlos Manuel MenesesThis Final Report of the Supervised Teaching Practice, carried out within the framework of the Master’s Degree in Ciências Religiosas at the Faculdade de Teologia da Universidade católica Portuguesa, presents the pedagogical experience developed at Escola Básica e Secundária da Sobreira during the 2024/2025 academic year, within the subject of Educação moral e Religiosa Católica (EMRC). The research stemmed from the observation of the limited presence of collaborative work proposals in EMRC textbooks, raising the question of whether group dynamics could foster more meaningful and inclusive learning. The intervention focused on the teaching unit As Origens, integrating cooperative methodologies that emphasized dialogue, co-responsibility, and the shared construction of knowledge. The analysis of the outcomes revealed that these strategies enhanced students’ engagement, strengthened social and relational competences, and consolidated learning in line with the curricular goals and the Profile of Students Leaving Compulsory Schooling. In summary, this report constitutes an action-research exercise that confirms the relevance of collaborative dynamics in promoting students’ integral formation and in contributing to the improvement of the teacher’s professional practice.
- From waste to bioactives: green extraction of natural antioxidants and antimicrobials from tomato by-productsPublication . Fernandes, Ana; Magalhães, Daniela; Souza, Hiléia K. S.; Campos, Débora A.; Boas, Ana A. Vilas; Pintado, ManuelaBackground: Global tomato production reached 192 million tons in 2023. Industrial processing generates around 25% by-products (peels, seeds, pulp), often discarded, yet rich in phenolics (e.g. quercetin, lutein), carotenoids (e.g. lycopene, ?-carotene), fiber and proteins. With growing demand for sustainable, biodegradable, and clean-label packaging materials, there is increasing interest in using natural bioactive compounds to replace synthetic additives [1]. The NOVAPACK project explores the potential of tomato by-products as sources of antioxidants and antimicrobials and pigments for use in active edible packaging, thereby supporting circular economy goals and reducing environmental impact. Methods: Tomato by-products were characterized in terms of proximal composition, and bioactive compounds were extracted using environmentally friendly, food-safe solvents: ethanol/water, citric acid, lactic acid, and ascorbic acid (HCl as reference). Extracts were analyzed using HPLC to determine the levels of carotenoid and phenolic compounds. FTIR spectroscopy was used to identify functional groups. Antioxidant capacity was tested with DPPH and ABTS assays. Antimicrobial effectiveness was evaluated against pathogens such as E. coli, B. cereus, S. aureus and Salmonella spp. Results: Tomato by-products showed proteins (20.50 ± 0.20%), total dietary fiber (65.89 ± 2.25%) and ash (2.96 ± 0.09%). Ethanol/water extracts yielded higher quercetin concentrations, while acidic solvents improved phenolic compounds diversity extracting rutin and naringenin. Carotenoids were efficiently recovered, yielding a total carotenoid content reaching 2.24 ± 0.03%, which played an important role in the observed antioxidant activity. FTIR analysis revealed hydroxyl and aromatic C=C groups, confirming the presence of phenolics and carotenoids. Antioxidant assays showed strong radical-scavenging activity, and antimicrobial tests indicated effective inhibition of the referred foodborne pathogens, with growth suppression at concentrations ranging from 0.01 % to 1 % w/v, with further optimization being still performed. Conclusions: This study highlights tomato by-products as sources of natural antioxidants and antimicrobials for active packaging. Green extraction methods exhibit strong potential, especially when applied within Mediterranean agrosystems. Findings support bio-based packaging that improves food safety, shelf-life, and waste valorization, aligning with NOVAPACK goals.
- Integrating traditional antifungal tests and flow cytometry to evaluate the activity of essential oils against Malassezia furfurPublication . Lopes, Ana I.; Oliveira, Cláudia S.; Pintado, Manuela E.; Tavaria, Freni K.Malassezia spp. are lipid-dependent yeasts that constitute a major part of the human skin mycobiome. While normally commensal, they can contribute to several dermatological conditions, with Malassezia furfur (M. furfur) being the species most often linked to invasive disease [1]. Current treatments for M. furfur infections rely on topical or systemic antifungals that, despite being effective, are constrained by side effects, drug interactions, species-specific resistance, and high recurrence rates [2]. In this context, essential oils (EOs) have gained attention as promising alternatives due to their broad-spectrum antimicrobial activity and multi-target mechanisms, which reduce the likelihood of resistance [3].