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Atitudes ambientais de adolescentes rurais e urbanos
Get PDFThe worldwide intensification of environmental problems has increased political debates and educational concerns about behaviors and citizens’ responsibilities. Studying the factors and dynamics of environmental attitudes is critical for environmental behaviors. However, studies regarding environmental attitudes throughout adolescence and considering rural and urban regions are lacking. This study investigated the environmental attitudes of early and middle adolescents, comparing rural and urban regions. The sample consisted of 1,262 students (53.6% women) who completed two environmental attitude inventories: one measuring ecocentrism (sustaining environmental preservation) and another measuring anthropocentrism (sustaining environmental utilization). Urban students presented higher anthropocentric attitudes than rural students. Early adolescents scored higher on ecocentric attitudes, whereas middle adolescents scored higher on anthropocentric attitudes. Urban students increased anthropocentric attitudes from early to middle adolescence, while rural students decreased ecocentric attitudes. The findings highlight developmental and contextual differences in environmental attitudes, which have implications for education and policy. We discuss recommendations for future research.Fundação para a Ciência e a Tecnologia, IP no âmbito da Unidade de Investigação e Desenvolvimento em Educação e Formação (Process nºUIDB/04107/2020)
Effect of melatonin implants on carcass characteristics and meat quality of slow-growing chickens
Get PDFThis study evaluated the effect of melatonin implants on carcass characteristics and meat quality of slow-growing broilers slaughtered at 43 and 97 days (d) of age. A total of 128 one day-old male broilers (Coloryeld) were randomly divided into two groups, which in turn were divided into 8 groups (replicates) of 8 broilers each one.
One group (64 animals) was the control group (C) and the other received a melatonin implant (18 mg melatonin per animal) at 8 d of age (M). The animals were reared for 97 d. For the first 42 d they were kept in an enclosed facility and then allowed access to the outside. Two culls were performed: one at 43 d and one at 97 d, randomly selecting 8 chicks from each group at each time (N = 8 × 2 × 2= 32). Carcass traits and meat quality were evaluated on these samples. Chickens slaughtered at older ages had higher dead-plucked, leg and carcass weights (P 0.05). Luminosity, tone and water activity decreased with melatonin implants at 43 d of age (P <0.001), whereas pH increased (P = 0.004). At 97 d after slaughter, meat yellowness was lower (P = 0.028) and firmness increased (P = 0.029). At both time points, melatonin caused reddening of the meat (P < 0.001). Lipid oxidisability tended to be reduced, extending the shelf life of the meat (P = 0.068). The fatty acid profile was little affected by the placement of the implants. Age and melatonin have different effects on the meat quality of slow-growing chickens. While age affects several factors such as texture and fatty acid profile, melatonin improves colour, water activity and lipid oxidation. Its use could improve preservation and extend the shelf life of meatResearch carried out with the Leonardo Scholarship for Researchers and Cultural Creators 2024 of the BBVA Foundation. We are also grateful to the Own Program III: Grants for Predoctoral Contracts of the University of Salamanca co-funded by Banco Santander
Separation of Bioactive Compounds in Olive Leaf with a Pyridyl-Functionalized Adsorbent and Hydroalcoholic Solvents
No full textThe separation of different types of bioactive compounds in olive leaf is demonstrated with a tailored adsorbent functionalized with pyridyl moieties and sorption−desorption processes developed to use only hydroalcoholic solvents. The competitive binding isotherms of mixtures of vanillic acid, oleuropein, quercetin, maslinic, and oleanolic acids in water/ethanol solvents, with the composition ranging from 50/50 up to 100% ethanol, prove the feasibility of the separation of such different classes of molecules. The bioactive compounds in two industrial olive leaf extracts with different crude compositions were separated with the pyridyl-based polymer particles in packed columns, employing multicycle sorption/desorption processes. A polyphenol-rich extract was subjected to separation, resulting in the isolation of fractions containing varying concentrations of specific compounds. For example, a fraction enriched with oleuropein exhibited a concentration of approximately 80% (an enrichment factor of ∼4 in comparison with the crude extract), while glycosylated flavonoids were present at a concentration of around 60% in another fraction (an enrichment factor of ∼12). Additionally, aglycone flavonoids were present in fractions at a concentration of approximately 83% (an enrichment factor of ∼49). On the other hand, the separation of polyphenols and triterpene acids in an olive leaf extract with a high triterpene content was also demonstrated, with a ratio of flavonoids to triterpenoids of approximately 23 in isolated fractions, as compared to approximately 1 observed in the crude extract. The developed approach yielded luteolin with an enrichment factor of approximately 7. These novel achievements are intended to contribute to sustainability and a circular bioeconomy through the efficient industrial valorization of agricultural by products.The authors acknowledge the support through the OLE-
AF4VALUE project. This project received funding from the
Bio-Based Industries Joint Undertaking under the European
Union’s Horizon 2020 research and innovation programme
under Grant Agreement No. 101023256. The authors also
thank NATAC for providing the olive leaf extracts and aid with
the identification by LC-MS of compounds they contained.
Rolando Dias is grateful to the Foundation for Science and
Technology (FCT, Portugal) for financial support through
national funds FCT/MCTES (PIDDAC) to CIMO (UIDB/
00690/2020 and UIDP/00690/2020) and SusTEC (LA/P/
0007/2020). Mário Rui Costa acknowledges support from LA/
P/0045/2020 (ALiCE), UIDB/50020/2020, and UIDP/
50020/2020 (LSRE-LCM), funded by national funds through
FCT/MCTES (PIDDAC)
Development of a database migration and compatibility system
Get PDFMestrado de dupla diplomação com o Centro Federal de Educação Tecnológica de Minas Gerais – CEFET-MGBiological hazards, such as bacteria, viruses, and parasites, pose significant threats to human health when encountered through inhalation, ingestion, or skin contact. The
Pathogens-in-Foods (PIF) database was established to address these concerns, serving as a centralized resource for accessing information about food borne pathogens in Europe. The European Food Safety Authority (EFSA) plays a pivotal role in ensuring food and feed safety within the European Union. However, the EFSA and PIF databases employ different data structures, making compatibility and data migration essential to enhance the relevance of PIF.
This thesis focuses on the development of a data migration and compatibility system, allowing seamless communication between the PIF and EFSA databases. Through this system, the databases can align their information more effectively, ultimately improving food safety and public health.
Using Python data migration scripts, it was possible to migrate the old PIF database to EFSA standards, making the two databases compatible. The script was developed
following a system of classes, making it possible to use these same classes for future migrations if necessary or even migrations to other databases.
The compatibility system developed offers the possibility of converting variables between different databases without the need for data migration. This system is especially useful for variables or entities that cannot or should not undergo the data migration process. In this way, the system operated as a conversion system, making PIF entities compatible with EFSA variables
Phenolic Compounds from Pyrus communis Residues: Mechanisms of Antibacterial Action and Therapeutic Applications
Get PDFThe food industry produces substantial amounts of fruit byproducts, which are often discarded despite their high content of bioactive compounds with potential therapeutic applications. Pyrus communis (pear) residues, which are particularly rich in phenolic compounds, represent a valuable yet underutilized resource. These byproducts have demonstrated significant antioxidant and antibacterial properties, suggesting their potential for medical and pharmaceutical applications. This review aims to provide a comprehensive analysis of the phenolic profile of P. communis byproducts, emphasizing their antioxidant and antibacterial mechanisms and their prospective use in combating oxidative stress and antibacterial resistance. Methods: A comprehensive review of the key phenolic compounds from P. communis residues was conducted using ScienceDirect and Google Scholar databases (from 2014 to 2024). Studies assessing antioxidant and antibacterial activities were reviewed, with a focus on their mechanisms of action against Gram-positive and Gram-negative bacterial pathogens. Results: A minimum of 14 distinct phenolic compounds were identified among P. communis residues. However, chlorogenic acid and catechin were identified as the primary contributors to the antioxidant activity of P. communis residues. Hydroquinone and chlorogenic acid exhibited strong antibacterial effects through membrane disruption, enzyme inhibition, and metabolic interference. Despite this potential, hydroquinone’s cytotoxicity and regulatory concerns limit its direct pharmaceutical application. Conclusions: While P. communis phenolics show promise as natural antibacterial agents, future research should address bioavailability, extraction standardization, and safe formulation strategies. Investigating their synergy with conventional antibiotics and improving stability for cosmetic applications are key steps toward their practical use. In vivo and clinical studies are crucial to validating their therapeutic potential and ensuring regulatory approval.This work was supported by projects UI/00772 and LA/P/0059/2020 and funded by the Portuguese Foundation for Science and Technology (FCT). This work was financially supported by national funds through FCT/MCTES (PIDDAC): CIMO, UIDB/00690/2020 (DOI: 10.54499/UIDB/00690/2020) and UIDP/00690/2020 (DOI: 10.54499/UIDP/00690/2020); and SusTEC, LA/P/0007/2020 (DOI: 10.54499/LA/P/0007/2020). Jessica Ribeiro acknowledges the financial support provided by FCT through her PhD grant (2023.00592.BD). The authors acknowledge the national funding provided by FCT through the institutional scientific employment program contract with L. Barros and S. A. Heleno, as well as the individual scientific employment program contract with F.S. Reis (2021.03728.CEECIND)
Anti-Proliferative, Anti-Inflammatory, In Vitro Wound Healing Potentials and Phenolic Content of Phlomis Crinita Cav. Extracts
No full textPhlomis crinita Cav. (P. crinita), a medicinal plant from the Lamiaceae family, is widely used as a natural remedy in traditional North African and Southern European folk medicine to treat lesions and burns through the application of its leaves This study aimed to investigate its biological activities, including antiproliferative, anti-inflammatory, and wound-healing properties. Hydromethanolic extracts were prepared from the leaves, flowers, and rhizomes. Phytochemical analysis determined total phenolic content (TPC) and flavonoid content (FC). Antiproliferative activity was evaluated using the sulforhodamine B (SRB) assay against five human tumor cell lines (AGS, Caco-2, HeLa, MCF-7, and NCI-H460), each derived from a carcinoma of a distinct organ. Anti-inflammatory activity was assessed by measuring nitric oxide production in LPS-stimulated RAW 264.7 macrophages. The wound-healing potential was evaluated using the scratch assay. Phytochemical analysis revealed significant variations in TPC and FC among the extracts, with the rhizome extract exhibiting the highest levels: TPC: 128.15 μg GAE/mg DW and FC: 46.91 μg QE/mg DW. All extracts demonstrated antiproliferative activity against the tumor cell lines, with the rhizome extract showing the most potent growth inhibition (GI50: 178.11 ± 4.10 μg/mL against AGS). The rhizome extract also exhibited the most potent inhibition of nitric oxide production (IC50: 152.42 ± 10.88 μg/mL) compared to the other extracts tested. In the wound-healing assay, leaf extract demonstrated comparable healing effects to Allantoin, a known wound-healing agent. Our findings support the notion that P. crinita can be considered a promising source of therapeutic bioactive compounds
Phytochemical diversity and biological activities of Hypericum japonicum and Hypericum sampsonii: potential for natural product-based food applications
Get PDFThis study characterizes two species of the genus Hypericum to envisage their applicability as effective and
versatile functional foods, dietary supplements, and food preservatives. A wide phenolic composition was found
in both extracts, highlighting flanovoids for H. japonicum and xanthones for H. sampsonii. Moreover, anthocya-
nins were analyzed for the first time in the latter plant. Antioxidant capacity was highlighted by oxidative he-
molysis inhibition assay (OxHLIA), where H. japonicum was more effective (lower EC50) than antioxidant Trolox
(16.3 < 21.8 μg/mL). H. sampsonii extract inhibited lipid peroxidation in the thiobarbituric acid reactive sub-
stances (TBARS) method (EC50 = 17.05 μg/mL) compared to Trolox (EC50 = 5.8 μg/mL). H. japonicum anti-
bacterial activity showed a minimum inhibitory concentration (MIC) of 0.007 mg/mL, even lower than the
control. These results indicate the bioactive potential of both extracts, as well as the importance of evaluating the
food-related bioactive components of medicinal plants and the mechanisms involved in their bioactivities.The research leading to these results was supported by MICIU/AEI/10.13039/501100011033 supporting the predoctoral industrial grant for A. Perez-Vazquez (DIN2024-013416) in collaboration with Mercantia Desarrollos Alimentarios S.L; by Xunta de Galicia for supporting the pre-doctoral grant of P. Barciela (ED481A-2024-230). This work was supported by national funds through FCT/MCTES (PIDDAC): CIMO, UIDB/00690/2020 (DOI: 10.54499/UIDB/00690/2020) and UIDP/00690/2020 (DOI: 10.54499/UIDP/00690/2020); and SusTEC, LA/P/0007/2020 (DOI:10.54499/LA/P/0007/2020). L. Barros (CEEC-INST, DOI: 10.54499/CEECINST/00107/2021/CP2793/CT0002) and C. Pereira thanks FCT through the institutional scientific employment program–contract for her contract; to the Agenda VIIAFOOD - Platform for Valorization, Industrialization and Commercial Innovation for Agrifood (no. C644929456-00000040) for T.C.S.P. Pires, D.B. Rodrigues and T. Silveira contract, a project supported under the PRR (www.recuperarportugal.gov.pt) and financed by the European Union /Next Generation EU. The authors are grateful to FEDER Cooperaci´on Interreg VI A Espanha – Portugal (POCTEP) 2021-2027 for financial support through the project 0033_NET4FOOD_1_P
Microbial and pest contamination in nuts: Radio frequency disinfestation and controlled atmosphere preservation – A review
Get PDFNuts are increasingly recognized for their rich nutritional profile and bioactive potential, making them a sig-
nificant economic contributor globally. However, the commercialization of nuts necessitates stringent quality
control measures to mitigate infestations by insect pests and microorganisms, which can lead to rapid deterio-
ration both pre- and post-harvest. Contamination often arises from inadequate practices in harvesting, packaging,
storage, and transportation, heightening the risk of pathogen infection and mycotoxin contamination. To address
these challenges, innovative preservation techniques are essential for enhancing food safety and extending shelf-
life without compromising quality. Radiofrequency (RF) technology has emerged as a promising solution in food
processing, utilizing volumetric heating for effective disinfestation, pathogen pasteurization, drying, and
blanching while maintaining product integrity. In contrast, Controlled Atmosphere (CA) storage employs gas
composition control to create low-oxygen environments that inhibit microbial growth during storage. This re-
view aims to provide a comprehensive overview of nut safety and preservation by identifying key contamination
sources and the microorganisms that target nuts. It will analyze the effectiveness of RF and CA technologies in
preserving and decontaminating nuts. By exploring these advanced methods, this study highlights their potential
to surpass conventional processes, ultimately improving nut safety and quality throughout the supply chain.This work was carried out under Agenda VIIAFOOD - Plataforma de Valorização, Industrialização e Inovação Comercial para o Agro-Alimentar (nº C644929456-00000040), a project supported under the
PRR (www.recuperarportugal.gov.pt), and financed by the European Union/Next Generation EU.
This work was also supported by national funds through FCT/MCTES (PIDDAC): CIMO, UIDB/00690/2020 (DOI: 10.54499/UIDB/00690/2020) and UIDP/00690/2020 (DOI: 10.54499/UIDP/00690/2020); and
SusTEC, LA/P/0007/2020 (DOI: 10.54499/LA/P/0007/2020). The authors are also grateful to the national funding by FCT, through the institutional and individual scientific employment program-contract
with L. Barros (CEEC-INST, DOI: 10.54499/CEECINST/00107/2021/CP2793/CT0002) and A. Fernandes (DOI:10.54499/CEECINST/00016/2018/CP1505/CT0008), respectively; and the PhD fellowship
2021.04585.BD of A. Libera
Comparison of nutritional and bioactive properties of acorn flour with and without tannins
Get PDFThe Quercus spp. are a varied group of evergreen and deciduous trees native to temperate and tropical regions. There are about 600 species of Quercus worldwide, which differ in their flowering and fruiting dynamics as well as maturity index. Acorns, the nuts of Quercus spp. trees, offer a comprehensive nutritional profile, being rich in proteins, fibers, starch, bioactive compounds including tannins and phenolic acids, essential vitamins, like vitamins A and E, and minerals, such as potassium, iron, calcium, and magnesium. However, this fruit presents a problem for the food industry regarding the astringency caused by tannins, which are anti-nutrients found in acorns. Therefore, this study aims to evaluate the potential of acorn flour for the baking industry by comparing the nutritional value and bioactive compounds of acorn flour with and without tannins. The whole flour (SPM21) and a tannin-free flour (SPM21F4) were analysed, having both been supplied by the company Landratech. The elimination of tannins, which was accomplished by leaching the flour three times with water at 15 °C, resulted in a reduction in several nutrients, such as crude protein, ash, and fiber. However, the SPM21F4 flour showed increased levels of moisture, crude fat, starch, total carbohydrates, and energy content. Soluble sugars were found exclusively in the SPM21 flour, indicating that the leaching treatment affected the sugar content in the SPM21F4 sample. The fatty acid profile of the SPM21F4 flour revealed higher levels of polyunsaturated fatty acid (PUFA) and monounsaturated fatty acid (MUFA), while the flour containing tannins had higher levels of saturated fatty acids (SFA). Ten phenolic compounds were detected, and the tannin free flour had a much lower overall phenolic content. In conclusion, properly processed acorn flour can improve the nutritional profile of bread by providing bioactive chemicals and appealing sensory features, hence increasing its popularity in the baking business. However, further research is needed to optimize tannin extraction and fully understand the nutritional and industrial potential of acorn flour.As espécies do género Quercus são um grupo variado de árvores perenes e decíduas nativas de regiões temperadas e tropicais. Existem cerca de 600 espécies de Quercus em todo o mundo, que diferem nas suas dinâmicas de floração e frutificação, bem como no índice de maturidade. As bolotas, os frutos das árvores deste género, oferecem um perfil nutricional abrangente, sendo ricas em proteínas, fibras, amido, compostos bioativos, incluindo taninos e ácidos fenólicos, vitaminas essenciais, como as vitaminas A e E, e minerais, como potássio, ferro, cálcio e magnésio. No entanto, este fruto apresenta um problema para a indústria alimentar devido à adstringência causada pelos taninos, um anti nutriente encontrado nas bolotas. Este estudo visa avaliar o potencial da farinha de bolota na indústria de panificação, comparando o valor nutricional e os compostos bioativos da farinha de bolota com e sem taninos. Foram analisadas farinhas com presença de taninos (SPM21) e uma farinha sem taninos (SPM21F4), sendo ambas as amostras fornecidas pela empresa Landratech. A eliminação dos taninos, realizada através da lixiviação da farinha três vezes com água a 15 °C resultou na redução de vários nutrientes, como proteína bruta, cinzas e fibras. No entanto, a farinha SPM21F4 apresentou um aumento nos níveis de humidade, gordura bruta, amido, carboidratos totais e conteúdo energético. Açúcares solúveis foram encontrados exclusivamente na farinha SPM21, indicando que o tratamento de lixiviação afetou o conteúdo de açúcar na amostra SPM21F4. O perfil de ácidos gordos da farinha SPM21F4 revelou níveis mais altos de ácidos gordos polinsaturados (PUFA) e monoinsaturados (MUFA), enquanto a farinha com taninos apresentou níveis mais altos de ácidos gordos saturados (SFA). Dez compostos fenólicos foram detetados, e a farinha sem taninos apresentou um conteúdo fenólico total muito menor. Concluindo, a farinha de bolota adequadamente processada pode melhorar o perfil nutricional do pão, fornecendo compostos bioativos e características sensoriais aliciantes, aumentando assim a sua popularidade na indústria de panificação. No entanto, serão necessários mais estudo de forma a otimizar a extração de taninos e entender completamente o potencial nutricional para a industrial de farinha de bolota.This work was funded through national funding from the Foundation for Science and Technology (FCT, Portugal), within the scope of the Project PRIMA Section 2 - Multitopic 2019: MEDACORNET - Resgate de bolotas como um Superalimento Tradicional Mediterrânico (PRIMA/0005/2022
Awareness of sustainability practices in construction: learning in a real context
No full textAs part of the Higher Professional Technical Course in Civil Construction at a Polytechnic Higher Education Institution, a teaching experience was proposed in which the Technical Installations and Sustainability Practices in Construction course units were taught interconnectedly. The studentsmobilized the knowledge acquired in the first-course unit to carry out practical work on more sustainable solutions in buildings as part of the second-course unit. This experience allowed the students to apply their knowledge in scenarios close to their professional reality and to reflect on the complex issues of sustainability in construction