Rede de Química e Tecnologia

The authentication of commercial herbal products such as herbal teas and infusions is essential to ensure consumer safety and product integrity. In this study, 100 commercial herbal infusions, including 94 single-species products and six polyherbal formulations, were analysed using DNA barcoding ( matK and rbcL ) and ITS2 metabarcoding. Moreover, the performance of two custom reference databases (NCBI and BOLD) was compared in ITS2 metabarcoding. DNA extraction was successful for 94 samples, while six single-species products failed to amplify any of the tested barcodes. Among the 88 remaining single-species samples, ITS2 showed the highest amplification success (100 %), outperforming the barcodes rbcL (94 %) and matK (84 %). Sanger sequencing confirmed the labelled species in 69.3 % of cases with rbcL and 48.9 % with matK . While 63 samples would be considered authentic solely based on barcoding (i.e., if either rbcL or matK matched the label), ITS2 metabarcoding revealed that many of these contained additional undeclared species, indicating that barcoding alone overestimated product authenticity. Of the 85 samples successfully analysed by ITS2 metabarcoding, only 27 (32 %) fully matched their label, while 58 (68 %) contained either additional undeclared species or complete substitutions. Several products contained undeclared species in significant proportions, indicating potential economic adulteration. Analysis of mock-mixtures demonstrated that ITS2 metabarcoding can approximate ingredient proportions, though recovery bias may occur. Overall, the results revealed (i) the importance of curated and comprehensive databases, with a higher number of species being identified by NCBI database, (ii) the superior sensitivity of ITS2 metabarcoding, and (iii) the widespread mislabelling in commercial herbal products. • The authenticity of 100 commercial herbal infusions was evaluated. • Results from two approaches, DNA barcoding and metabarcoding, were compared. • Two custom reference databases (NCBI and BOLD) were developed for ITS2 metabarcoding. • ITS2 metabarcoding revealed a high level of adulteration (68 %). • ITS2 allowed the detection of fungal contaminants in some samples.

The highly stable metal-organic framework (MOF) composed of [Zr 6 O 4 (μ 3 -OH) 4 (OH) 6 (H 2 O) 6 (BTC) 2 ]·nH 2 O units (MOF-808) was modified by incorporating gold (Au) nanoparticles and functional groups to enhance electrocatalytic activity for the borohydride oxidation reaction (BOR). Three composite materials (Au@MOF-808, Au@MOF-808-NH 2 , and Au@MOF-808-SH) were prepared by the incorporation of Au in structurally related MOFs, MOF-808, MOF-808-NH 2 , and MOF-808-SH, respectively. These composite materials were evaluated as anodic electrocatalysts for BOR in alkaline media using cyclic voltammetry and chronoamperometry. Among the prepared materials, Au@MOF-808-NH 2 exhibited the highest BOR activity, with an apparent activation energy of 15.3 kJ mol −1 , a reaction order of 0.6, an anodic charge transfer coefficient of 0.63, and a number of exchanged electrons of 4.4. The latter was significantly below the theoretical eight-electron value, indicating the presence of alternative reaction pathways. Notably, this material achieved a high mass-specific BOR peak current of 4.23 A μg Au −1 , demonstrating outstanding electrocatalytic efficiency despite the ultralow noble metal loading. These results underscore the potential of Au@MOF-808-NH 2 as a cost-effective and scalable anodic electrocatalyst for high-performance direct borohydride fuel cells. • Ultralow Au-loaded functionalized MOF-808 boosts borohydride oxidation reaction (BOR). • Au@MOF-808-NH 2 shows the highest BOR activity among the prepared composites. • Record-high mass activity of 4.23 A μg Au −1 achieved with Au@MOF-808-NH 2 electrocatalyst. • A low activation energy of 15.3 kJ mol −1 suggests an efficient BOR pathway. • BOR mechanism involves partial BH 4 − hydrolysis, as implied by a 4.4-electron transfer behaviour.

Abstract Enterovirus D68 (EV-D68) is a reemerging respiratory pathogen that is increasingly associated with severe respiratory disease and occasional neurological complications, yet its circulation in Portugal remains poorly documented. In the present study, we conducted molecular surveillance in southern Portugal (Algarve region) from October 2024 to February 2025. Screening of 150 respiratory samples from patients (115 from children and 35 from adults), all positive for rhinovirus/enterovirus, revealed eight EV-D68–positive cases, corresponding to a detection rate of 5.44%, spanning a broad age range from infancy to the elderly. Clinical manifestations ranged from mild respiratory illness to severe conditions, including pneumonia and acute respiratory distress syndrome. In addition, neurological involvement such as complex febrile seizures and encephalomyelitis was observed. Some cases involved coinfections, while others presented with EV-D68 as the sole detected pathogen. Genomic characterization from one isolate revealed a VP1 fragment belonging to clade B3, and a complete genome from another isolate clustered within clade A2. Phylogenetic analysis confirmed clustering with contemporary European isolates. These findings highlight the circulation of multiple EV-D68 clades in Portugal, underscore the clinical diversity of infections, and reinforce the importance of genomic surveillance to monitor viral evolution and potential public health impact.

Gas hydrates are of great relevance to both the oil industry and the environment. Understanding how these solid structures nucleate from aqueous solutions is essential for controlling their formation. Experimental studies have often suggested that hydrate nucleation originates at the interface between the aqueous phase and the guest-molecule reservoir. To assess this hypothesis, we perform molecular dynamics simulations of CO2 hydrate nucleation. First, we place hydrate seeds at different positions relative to the interface and monitor their evolution, finding that seeds embedded in the bulk are more likely to grow than those located near or at the interface. Second, we analyze spontaneous nucleation simulations with and without an interface. Our previous work showed that nucleation rates are indistinguishable in both systems, strongly indicating that the interface does not play a role. Here, trajectory analysis reveals that hydrates nucleate in regions of locally high CO2 concentration, which arise spontaneously in the bulk and are not associated with the interface. Our results indicate that hydrate nucleation does not preferentially occur at the interface, at least under the deep supercooling conditions explored in this work. Further work at higher temperatures, and considering alternative nucleation locations, is needed to reconcile experiments and simulations, and thereby reach a deep understanding of the mechanism of hydrate formation.

Global water scarcity, intensified by population growth, economic development, and climate change, presents a significant challenge, with the cosmetics industry contributing heavily to water demand. Simultaneously, the cork industry generates substantial amounts of cork boiling wastewater (CBW), an acidic effluent with environmental hazards. This study explored CBW’s potential for cosmetic application, focusing on safety, physicochemical properties, and suitability for incorporation in cosmetic formulations. Three CBW samples (A, B and C) were analyzed for pH, conductivity, turbidity, density, 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity, and total phenolic content. CBW A displayed suitable physicochemical properties and potential antioxidant activity and was selected for further investigation. Human keratinocyte viability was assessed using CBW A before and after adsorption treatment with silica (TCBW A) to reduce cytotoxicity. CBW A was more toxic to human keratinocytes compared to control water, but treatment improved cell viability. This treatment had minimal impact on physicochemical parameters, aside from reducing phenolic content. Metal concentrations in TCBW A remained within cosmetic safety limits. TCBW A was incorporated into an oil-in-water (O/W) cream, which was further evaluated for pH, droplet size, rheological behavior, textural properties, and stability. The resulting cream was homogeneous, woody-scented, with uniform droplet size and stable after centrifugation. TCBW A incorporation provided suitable rheological behavior and formulation stability after 90 days of storage at 25 °C. These findings indicate that TCBW A has low cytotoxicity, suitable physicochemical properties, and provides stable cosmetic formulations, highlighting its potential as a sustainable ingredient for the cosmetic industry.

Soil electrical conductivity (EC) and aggregate-size distribution are critical indicators of soil salinity risk, structural integrity, and overall soil health. We assessed the status of these properties in 188 wheat plots across nine European pedoclimatic zones to quantify the influence of climate and agricultural management. Most soils (~88%) were non-saline, 9% slightly saline, and 3% moderately saline, with the highest salinity in Mediterranean regions. EC was generally lower under organic management, reflecting higher soil organic carbon, improved porosity, and enhanced cation retention. Soils were dominated by small macroaggregates (250–2000 µm) and large microaggregates (53–250 µm), together accounting for an average of 73% of total aggregates. Climate was the primary determinant of both EC and aggregate distribution, with drier and warmer conditions promoting salinization and smaller aggregate sizes, whereas wetter conditions favored macroaggregate formation. Agricultural management had a secondary but context-dependent effect, particularly on soil aggregation, with organic farming, integrated organomineral fertilization, crop residue incorporation, and legume rotations enhancing macroaggregate formation, especially in low-SOC soils. These results indicate that pedoclimatic conditions largely shape soil salinity and structure, but adopting targeted, site-specific management practices can sustain soil health and mitigate risks related to salinity and structure, particularly under projected climate change.

Background/Objectives: The study investigated the anti-inflammatory potential of neolignan derivatives of dehydrodieugenol (CP1–CP5), focusing on the inhibition of secretory phospholipase A2 (sPLA2), a key enzyme in inflammation. Methods: Comprehensive quantitative docking analysis using four independent algorithms (PLP, ASP, ChemScore, GoldScore) revealed exceptional multitarget binding profiles for CP1 and CP2, with scores consistently above activity thresholds for acetylcholinesterase (AChE), cyclooxygenase-2 (COX-2), and sPLA2 from Crotalus durissus terrificus in both monomeric (Mcdt) and quaternary (Tcdt) forms. Results: Among the compounds, CP1 demonstrated the highest predicted affinity (AChE: 78.5, COX-2: 83.8, sPLA2: 82.7–83.4) and most potent experimental activity, reducing sPLA2 catalytic velocity through mixed-type inhibition involving the active site (His47, Asp48) and Ca2+ binding loop. In vivo assays in sPLA2-induced paw edema demonstrated that CP1 and CP2 achieved remarkable anti-inflammatory effects (up to 68.3% reduction), significantly exceeding their protective potential by direct enzyme inhibition, confirming the multitarget mechanism. The strong correlation between predicted docking scores and paw edema reduction (R2 = 0.89, p < 0.01) creates a firm foundation for establishing structure–activity relationship explanations. Conclusions: These findings highlight an integrated mechanism involving: (1) partial sPLA2 modulation, (2) neuroimmune regulation via AChE inhibition, and (3) prostaglandin synthesis blockade through COX-2 inhibition. This multitarget approach, combined with the natural origin of the compounds, positions dehydrodieugenol derivatives as promising candidates for developing therapies against complex inflammatory diseases, offering significant advantages over single-target strategies.