Biblioteca Digital do IPB
Publications Repository of the Polytechnic Institute of Bragança
Recent Submissions
Nutrients, Phytochemicals, and In Vitro Antioxidant and Antimicrobial Activities of Lulo (Solanum quitoense Lam.) Fruit Pulp, Peel, and Seeds
Publication . Añibarro-Ortega, Mikel; Dias, Maria Inês; Petrović, Jovana; Pereira, Alexis; Soković, Marina; Barros, Lillian; Pinela, José
Lulo or naranjilla (Solanum quitoense Lam.) is an Andean fruit with a sour and refreshing flavor, widely used in the preparation of juices and sweets. Despite its potential for international markets, it remains largely unknown outside its native regions, and most existing studies have focused on the whole fruit or its juice. This study investigated the nutritional and phenolic profiles of the peel, pulp, and seeds of S. quitoense using official food analysis methods and chromatographic techniques. In addition, the in vitro antioxidant activity and antimicrobial effects against foodborne fungi and bacteria were assessed. The peel was rich in ascorbic acid (25.2 mg/100 g fw), alpha-tocopherol (7.9 mg/100 g fw), dietary fiber (16.5 g/100 g fw), macrominerals (Na, Ca, K), and flavonoids (14.2 mg/g extract); the pulp contained high levels of citric acid (4.22 g/100 g fw) and sucrose (2.7 g/100 g fw); and the seeds stood out for their contents of trace elements (Zn, Cu, Mn, Fe), oleic acid, and spermidine-derived phenolamides (37.8 mg/g extract). Hydroethanolic extracts showed antioxidant activity by inhibiting lipid peroxidation and oxidative hemolysis, with the seed extract exhibiting the strongest antifungal effect against Aspergillus versicolor, likely due to its high spermidine derivative content. These findings shed light on the potential of S. quitoense fruit for the development of functional foods, antioxidant-rich beverages, and nutraceutical products.
A Comprehensive Review of Fused Filament Fabrication: Numerical Modeling Approaches and Emerging Trends
Publication . Enriconi, Maria; Rodriguez, Rocío; Araújo, Márcia; Rocha, João; García-Martín, Roberto; Ribeiro, J.E.; Pisonero, Javier; Rodríguez-Martín, Manuel
Fused Filament Fabrication (FFF) has become a widely adopted additive manufacturing technology due to its cost-effectiveness, material versatility, and accessibility. However, optimizing process parameters, predicting material behavior, and ensuring structural reliability remain major challenges. This review analyzes state-of-the-art computational methods used in FFF, which are categorized into four main areas: melt flow dynamics, cooling and solidification, thermal-mechanical behavior, and material property characterization. Notably, the integration of Computational Fluid Dynamics (CFD) and Finite Element Analysis (FEA) has led to improved predictions of key phenomena, such as filament deformation, residual stresses, and temperature gradients. The growing use of fiber-reinforced filaments has further enhanced mechanical performance; however, this also introduces added complexity due to filler orientation effects and interlayer adhesion issues. A critical limitation across existing studies is the lack of standardized experimental validation methods, which hinders model comparability and reproducibility. This review highlights the need for unified testing protocols, more accurate multi-physics simulations, and the integration of AI-based process monitoring to bridge the gap between numerical predictions and real-world performance. Addressing these gaps will be essential to advancing FFF as a precise and scalable manufacturing platform.
Developing epidemiological preparedness for a plant disease invasion: Modelling citrus huánglóngbìng in the European Union
Publication . Ellis, John; Lázaro, Elena; Duarte, Beatriz; Magalhães, Tomás; Duarte, Amílcar; Benhadi-Marín, Jacinto; Pereira, José Alberto; Vicent, Antonio; Parnell, Stephen; Cunniffe, Nik J.
Societal Impact Statement
Huánglóngbìng (HLB) is a bacterial disease of citrus that has significantly impacted Brazil and the United States, although citrus production in the Mediterranean Basin remains unaffected. By developing a mathematical model of spread in Spain, we tested surveillance and control strategies before any future HLB entry in the EU. We found while some citrus production might be maintained by roguing, this requires extensive surveillance and significant chemical control, perhaps also including testing of psyllids (which spread the pathogen) for bacterial DNA. Our work highlights the key importance of early detection (including asymptomatic infection) and vector control for HLB management.
Summary
• Huánglóngbìng (HLB; citrus greening) is the most damaging disease of citrus worldwide. While citrus production in the United States and Brazil have been affected for decades, HLB has not been reported in the European Union (EU). However, a HLB vector, the African citrus psyllid, is already in Portugal and Spain. In 2023, the major vector, the Asian citrus psyllid, was first reported in Cyprus.
• We develop a landscape-scale, epidemiological model, accounting for heterogeneous citrus cultivation and vector dispersal, as well as climate and disease management.
We use our model to predict HLB dynamics for an epidemic vectored by the African citrus psyllid in high-density citrus areas in Spain, assessing detection and control strategies.
• Without disease management, we predict large areas infected within 10–20 years. Even with significant visual surveillance, any epidemic will be widespread on first detection, making eradication unlikely. Nevertheless, increased inspection and roguing following first detection, particularly if coupled with intensive insecticide use, could sustain some citriculture for a decade or more, albeit with reduced production. However, effective control may require chemical application rates and/or active substances no longer authorised in the EU. Strategies targeting asymptomatic infection will be more successful. Detection of bacteriliferous vectors—sometimes possible long before plants show symptoms—could reduce lags before disease management commences. If detection of HLB-positive vectors were followed by intensive insecticide sprays, this may greatly improve outcomes.
• Our work highlights modelling as a key component of developing epidemiological preparedness for a pathogen invasion that is, at least somewhat, predictable in advance.
Improving Information on Over-looked Generalists: Occurrence and Mitochondrial DNA Diversity of Campbell’s (Cercopithecus campbelli) and Green Monkeys (Chlorocebus sabaeus) in Guinea–Bissau, West Africa
Publication . Colmonero-Costeira, Ivo; Djaló, Saidil Lamine; Nelson, Fernandes; Borges, Filipa; Aleixo-Pais, Isa G.; Gerini, Federica; Costa, Mafalda; Minhós, Tânia; Silva, Maria Joana Ferreira da
Non-threatened primates are often overlooked in conservation efforts despite their increasing vulnerability to local extirpation. Campbell’s (Cercopithecus campbelli) and green monkeys (Chlorocebus sabaeus) are sympatric medium-sized West African guenons (tribe Cercopithecini) whose intraspecific genetic diversity remains understudied in most of their distribution. Both species are ecological generalists and are globally considered non-threatened. In Guinea–Bissau, C. campbelli and Chl. sabaeus are considered the most abundant of the ten extant primate species and are the most frequently hunted for meat. Their populations are thought to be decreasing and but up-to-date data on their occurrence in the country hinders their conservation status assessment. We aimed to update occurrence data and estimate the country-wide mitochondrial (mtDNA) genetic diversity for both species in Guinea–Bissau. From 2008–2022, we conducted surveys in four mainland protected areas and on the islands of the Bijagós Archipelago. We identified C. campbelli populations outside their known distribution. We found high mtDNA diversity for both species on the mainland and lower diversity in insular populations. Our results show significant signals of geographically induced mtDNA differentiation, particularly in C. campbelli. In Chl. Sabaeus, we found divergent haplotypes at geographically close locations. We identified differentiated haplogroups with an estimated divergence time of 1.53 million years ago (Ma) in C. campbelli and 1.16 Ma in Chl. sabaeus, possibly linked to Pleistocene climatic fluctuations. Given the local presence of differentiated mtDNA haplogroups across these and other primate species, we suggest that Guinea–Bissau should be considered as an important region for primate conservation in West Africa.
Nutritional and Biochemical Assessment of Edible Fruits From Angola's Native Flora
Publication . Rangel, Josefa; Liberal, Ângela; Pires, Tânia C.S.P.; Finimundy, Tiane C.; Barros, Lillian; Monteiro, Filipa; Romeiras, Maria M.; Fernandes, Ângela
Angola's native flora hides a wealth of underexplored edible fruits with significant nutritional and bioactive potential. This study provides a comprehensive evaluation of the physicochemical and bioactive potential of some less explored edible fruits from this country, namely Annona muricata, A. squamosa, A. senegalensis, A. boehmii, Dacryodes edulis, and Strychnos spinosa. Nutritional profiling revealed carbohydrates as the predominant macronutrient, with A. muricata exhibiting the highest concentration (93.3 g/100 g dw). D. edulis, in turn, stood out for its high fat content (40.5 g/100 g dw), while A. senegalensis contained the highest protein levels (15-6 g/100 g dw). Free sugars analysis highlighted A. squamosa for its elevated fructose and glucose levels, contributing to its pronounced characteristic sweetness, whereas D. edulis exhibited minimal sugar content (1.27 g/100 g dw). Organic acid profiling revealed malic acid as dominant. Saturated fatty acids were predominant across most fruits, with A. boehmii showing the highest levels (71.6%), while A. senegalensis was enriched in monounsaturated fatty acids (45.15%). The phenolic analysis revealed a rich profile in bioactive compounds, with A. muricata and A. squamosa exhibiting significant levels of quercetin-3-O-rutinoside, while A. boehmii, S. spinosa, and D. edulis were characterized by distinct major phenolic compounds, such as cyanidin-3-O-glucoside, isorhamnetin-3-O-glucoside, and corilagin, respectively. Antioxidant activity was strongest in D. edulis and A. senegalensis (EC50 = 0.18 and 0.25 mu g/mL, respectively), while A. squamosa exhibited notable antibacterial activity (MIC = 0.3 mg/mL). This study underscores the nutritional and bioactive potential of Angola's native fruits, highlighting their applications in the food, nutraceutical, and pharmaceutical industries.