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Browsing by Issue Date, starting with "2025-11-01"

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  • Biofunctional silk sericin hydrogels: a versatile platform with potential for tissue healing and regeneration
    Publication . Veiga, Anabela; Ribeiro, Viviana; Ramírez-Jiménez, Rosa Ana; Aguilar, Maria Rosa; Rojo, Luis; Oliveira, Ana L.
    Discarded silk sericin protein (SS) presents a high yet underexplored potential as a biomaterial for tissue engineering (TE). Despite its biocompatibility, antioxidant activity, and moisture retention properties, its poor stability in aqueous media has limited broader application. In this work, we developed and characterized SS-based hydrogels using tannic acid (TA) and horseradish peroxidase (HRP) crosslinking systems to address these limitations and expand their use in skin TE. Hydrogels were prepared using SS concentrations of 2.5 % and 5 % (w/v) and evaluated for rheological behavior (G′ ranging from 100 to 10,000 Pa), swelling (up to 24 %), retention capacity (stable over 24–30 h), and degradation in proteolytic environments (mass loss ranging from ∼0–11 %, depending on formulation). TA-crosslinked hydrogels showed strong fluid retention and are suitable for high-moisture 3D wound dressings and coating applications. HRP-crosslinked hydrogels demonstrated tunable mechanical properties, shear-thinning behavior, and full recovery post-deformation, making them ideal for use as bioinks in 3D bioprinting and injectable matrices. In vitro assays confirmed cytocompatibility, with viability exceeding 85 %, and successful cell encapsulation and proliferation. Overall, this study presents a versatile SS-based hydrogel platform with potential for various biomedical applications, particularly in skin tissue healing and regeneration.
    2025-11-01Research article Open access Show more
  • Rice okara flours as sustainable protein ingredients for snack crackers: characterization and sensory evaluation
    Publication . Cassoni , Ana Carolina; Brassesco, María E.; Calixto, João; Duarte, Tiago; Correia, Daniela; Pintado, Manuela E.
    Aim: The valorization of rice okara by-products for food applications remains underexplored. This study aimed to evaluate the functional potential of four rice okara flours produced by SimpleYeast: dehydrated (OAD), thermally treated (OAT), enzymatically treated 1 (OAE1), and enzymatically treated 2 (OAE2), and their application in the development of protein-enriched salty crackers. Method: Physicochemical and functional properties of the flours were determined: protein content, color parameters (L*, a*, b*), water activity (aw), moisture, water and oil holding capacity, solubility, and degree of hydrolysis (TNBS assay). Salty crackers were formulated incorporating 15% of each flour type (CD, CT, CE1, CE2). Consumer acceptance was assessed through sensory analysis by untrained panellists. Results: The thermal and enzymatic treatments influenced color and water activity. ANOVA showed significant differences in L* values (p < 0.001), with OAE2 (enzymatic treatment 2) being markedly darker (43.9 ± 1.0) and more yellowish (b* = 21.1 ± 0.8) compared to OAD (64.8 ± 1.0; 9.5 ± 0.1), OAT (58.8 ± 0.7; 10.1 ± 0.1), and OAE1 (54.7 ± 0.5; 11.3 ± 0.2). a* values were also highest for OAE2 (8.2 ± 0.4). Water activity differed significantly (p < 0.001), with OAE2 having the highest value (0.5 ± 0.0), compared to 0.3–0.4 in the other samples. Enzymatic treatments enhanced solubility and hydrolysis degree. All flours maintained high protein content (~70%). High-protein salty crackers (~20%) produced with thermally treated okara (CT) received the highest overall consumer preference, followed by CE2 (enzymatic treatment 2), CE1 (enzymatic treatment 1), and CD (dehydrated). All prototypes were positively accepted and considered appealing, with higher scores for versions with treated flour. Conclusion: The study demonstrated that rice okara flours can be effectively valorized into high-protein functional ingredients for food applications. Thermal and enzymatic treatments improved functional properties and consumer acceptability of crackers, with thermally treated okara showing the best sensory performance. These results highlight the potential of these sustainable ingredients in the development of protein-rich snack products.
    2025-11-01Conference object Open access Show more
  • Effects of ultrasonication and high hydrostatic pressure on functional, thermal, structural, rheological, and pasting properties of gluten-free substitutes for enhanced breadmaking
    Publication . Mahsa, Farrokhi; Ramos, Inês N.; Silva, Cristina L. M.
    The demand for gluten-free (GF) products has increased due to the rising prevalence of gluten-related disorders. However, GF products often face challenges related to nutritional value, techno-functional, and structural properties. To address these challenges, researchers are investigating GF flours, starches, and protein isolates from pulses, cereals, and pseudocereals. However, in their native forms, these ingredients show poor stability, low solubility, and a high tendency for retrogradation, limiting their suitability for high-quality GF formulations. Techno-functional and structural modifications are essential to overcoming these limitations. Ultrasound (US) and high hydrostatic pressure (HHP) are innovative processing techniques that can enhance GF ingredients' techno-functional and nutritional properties while maintaining product integrity. This review examines the effects of US and HHP on the structural, techno-functional, thermal, pasting, and rheological properties of GF ingredients, from pulses, cereals, and pseudocereals, and their implications for breadmaking. Research indicates that US decreases water absorption capacity (WAC) but enhances solubility, while HHP increases WAC at higher intensities and decreases solubility. Both treatments reduce particle size, with HHP inducing more pronounced morphological changes. Additionally, both techniques lower gelatinization temperatures and enthalpy, improving dough hydration. Rheological studies suggest that US and HHP promote gel-like behavior, increasing the elastic modulus and reducing viscosity parameters, ultimately enhancing dough handling and bread structure. In conclusion, US and HHP show great potential for improving dough performance, bread volume, and texture in GF baking. However, optimizing treatment conditions is crucial, as their effects depend on the type of flour, starch, or protein and processing parameters.
    2025-11-01Research article Open access Show more
  • Short-pulse direct laser writing of 3Y-TZP zirconia: a superior surface modification strategy for enhanced resin bonding and adhesion durability
    Publication . Sahoo, Narayan; Carvalho, Óscar; Özcan, Mutlu; Eyüboğlu, Tan Fırat; Souza, Júlio C. M.; Silva, Filipe; Henriques, Bruno
    The clinical success of zirconia-based restorations relies on surface modifications that enhance adhesion without compromising material integrity. This study evaluates Direct Laser Writing (DLW) as a non-contact, contamination-free alternative to conventional grit-blasting methods (alumina particle abrasion [SB] and silica-coated alumina treatment [SC]. Surface roughness (Ra), wettability, surface free energy (SFE), phase transformation, and shear bond strength (SBS) were assessed. Zirconia specimens (N = 40) underwent DLW at two distinct parameters (DLW35, DLW10) or conventional grit-blasting (SB, SC). Surface characterization included roughness measurements, contact angle analysis, and SFE calculation (Owens-Wendt method). Phase transformation was quantified using X-ray diffraction (XRD). SBS tests between zirconia and resin-matrix cement were performed under water storage and thermocycled conditions. Results showed DLW provided controlled, uniform roughness comparable to grit-blasting without inducing mechanical damage or contamination. DLW-treated surfaces exhibited significantly better wettability and higher SFE. SBS values were statistically similar across all groups, indicating stable adhesion performance under both dry and thermocycled conditions. DLW preserved the tetragonal zirconia phase substantially better (DLW35: 93 %, DLW10: 85 %) compared to grit-blasted surfaces (SB: 76 %, SC: 68 %), minimizing residual stress and microstructural damage. The study concludes DLW is a superior zirconia surface treatment, offering precise control, contamination-free surfaces, enhanced wettability, and maintained microstructural integrity, making it ideal for dental, maxillofacial, and orthopedic applications.
    2025-11-01Research article Open access Show more
  • Overview of polyphenolic composition and related biological activities of grape stems
    Publication . Dias-Costa, Rui; Coelho, Marta; Domínguez-Perles, Raúl; Gouvinhas, Irene; Barros, Ana Novo
    Grape stems, or stalks, are lignocellulosic by-products removed during the destemming process to reduce astringency in wine production. These by-products are a notable source of minerals and polyphenolic compounds, such as phenolic acids, stilbenes, proanthocyanidins and catechin derivatives, flavonols, flavones, and anthocyanins. These bioactive compounds have been associated with several beneficial effects on human health, including the promotion of wound healing and antimicrobial, anti-inflammatory, anti-aging, anti-cancer, and antioxidant activities. Despite this potential, grape stems are still underutilised and are commonly disposed of through composting, landfilling, landfarming, or diverted to animal feed. This review offers an updated and detailed overview of the polyphenolic composition and biological activities of grape stems, highlighting their potential for application in innovative products. Their use could contribute to the advancement of sustainable practices through circular economy strategies and industrial symbiosis.
    2025-11-01Review article Open access Show more
  • Evaluating pomegranate seed oil for potential topical applications: safety, anti-inflammatory activity and wound healing in skin cell models
    Publication . Costa, Eduardo M.; Machado, Manuela; Pintado, Manuela; Silva, Sara
    Pomegranate seed oil (PSO), a by-product of pomegranate juice production, has a long-standing role in traditional medicine, yet is mechanistic and pharmaceutical potential for skin applications remains unexplored. This work explored the bioactivity of PSO in human keratinocytes (HaCaT) and dermal fibroblasts (HDFa) through evaluation of its impact upon cellular metabolism, anti-inflammatory properties and wound healing capacity. The data obtained showed that PSO exhibited no cytotoxic effects up to 500 µg/mL and significantly suppressed pro-inflammatory cytokines (IL-6, IL-8, TNF-?) under LPS-induced inflammatory conditions. Furthermore, wound closure in fibroblasts was accelerated by approximately 20% in a 24-h period. Although antioxidant activity was limited under induced oxidative stress, PSO exerted mild protective effects under basal conditions and fatty acid profiling revealed a PUFA-rich composition, including dihomolinolenic and punicic acids, potentially linked to the observed impact upon cellular metabolism. Overall, these findings offer novel insights into PSO’s dual functionality in skin regeneration and immune modulation, supporting its application as a bioactive ingredient for advanced topical therapies.
    2025-11-01Research article Embargoed access Show more
  • Innovative sampling strategies for trace metals analysis in water monitoring
    Publication . Ribas, Tânia C. F.; Pereira, Mafalda G.; Rodrigues, Francisco A. P.; Mesquita, Raquel B. R.; Rangel, António O. S. S.
    2025-11-01Conference object Embargoed access Show more
  • Sequential injection lab-on-valve with bead injection for iron speciation in waters
    Publication . Pereira, Mafalda G.; Ribas, Tânia C. F.; Moniz, Tânia; Rangel, Maria; Mesquita, Raquel B. R.; Rangel, António O. S. S.
    2025-11-01Conference object Embargoed access Show more
  • 2025-11-01Journal editorial Open access Show more
  • 2025-11-01Research article Open access Show more