Maria Paula Duarte

Periploca chevalieri (Apocynaceae Juss.) is an endemic medicinal plant from Cabo Verde that has long been used in traditional medicine, particularly for the management of diabetes and cough. However, to date, no studies focusing on potential adverse effects compromising its safe use have been performed. The present study aimed to investigate the safety profile of a standardized 70% hydroethanolic extract of Periploca chevalieri aerial parts (PcEE) using complementary in vivo and in vitro toxicological approaches. Repeated oral toxicity of PcEE at doses of 170, 600, and 1000 mg/kg body weight was evaluated in CD-1 mice over 14 days. Clinical signs, body weight, and food intake were monitored, as well as important biochemical parameters (hepatic, renal, and pancreatic biomarkers). Genotoxicity was investigated using the bacterial reverse mutation assay (Ames test) with five different strains of Salmonella Typhimurium in the presence and absence of a metabolizing system. The results obtained showed no significant variations (p < 0.05) in body weight of the animals treated with PcEE at all tested doses. Significant changes (p < 0.05) with negligible relevance were observed in the biochemical parameters of PcEE-treated groups compared to the control group. The Ames test results showed that PcEE did not produce genotoxic effects in any of the tested strains at concentrations up to the maximum tested concentration (5 mg/plate). The results obtained are an important step towards the support and validation of the use of P. chevalieri aerial parts in traditional medicine.

Fish is a food of high nutritional value, being an important source of proteins, fat, vitamins, and essential minerals. Atlantic horse mackerel is also rich in omega-3 polyunsaturated fatty acids (n3-PUFAs), recognized for their benefits to cardiovascular and neurological health. However, this composition also makes it highly susceptible to lipid oxidation, reducing its shelf life. Oxidation is accelerated by high water activity and near-neutral pH, conditions common in fish and processed products such as fish burgers. This work aimed to develop fish burgers incorporated with bioactive extracts (protein hydrolysates from cod fish processing by-product—PH, or green tea extract—GTE) and study their shelf life. The PH was recovered from cod frames using subcritical water extraction, and GTE with hydro-alcoholic extraction. The fish burgers were prepared using minced fish meat incorporated with 1% (w/w) of extracts, in four formulations: (i) 1% (w/w) of PH; (ii) 1% (w/w) of GTE; (iii) a combination of both extracts at 0.5% (w/w) each; and (iv) control without extracts. Physical–chemical, antioxidant and microbiological analysis of the burgers was performed to evaluate their preservation over 6 days of refrigerated storage. Compared to the control, samples with only GTE or the combined GTE + PH presented a delay in oxidation (50% less in TBARS) and microbiological deterioration (reduction of 0.5–1.8 Log CFU/g in total psychrotropic microorganisms). No significant changes were observed in the fish burgers incorporated with only PH. The results demonstrate that the incorporation of bioactive extracts has potential in reducing oxidative degradation and improving microbiological stability in fish-based products; however, superior doses must be used. Moreover, the use of natural extracts aligns with current consumer demand for clean-label and functional foods.

Fish processing by-products represent an abundant source of valuable biomolecules that can be valorized through sustainable extraction approaches. In this work, cod backbone hydrolysates obtained by subcritical water hydrolysis were incorporated into chitosan-based films for potential food packaging applications. The hydrolysis residue, rich in minerals, particularly hydroxyapatite (HAp residue), was also incorporated into the films to maximize the utilization of all hydrolysis-derived fractions. The effects of hydrolysate and HAp residue incorporation on the properties of the films were evaluated. The hydrolysate incorporation significantly improved the tensile strength of the films (from 11.56 to 24.39 MPa) and reduced water vapor permeability (from 4.93 to 2.89 (×10⁻¹¹) mol.m.m⁻².s⁻¹.Pa⁻¹), suggesting the formation of a denser and cohesive polymer network. However, the films also exhibited increased swelling and solubility (22–29% and 231–561%, respectively). When adding HAp residue, the films showed lower visible light transmittance and higher opacity, demonstrating improved light barrier properties. The addition of HAp residue also reduced swelling capacity but increased water vapor permeability and decreased tensile strength, suggesting the formation of a more heterogeneous film structure. Overall, the results demonstrate that cod backbone hydrolysates can be an alternative additive to chitosan films to tailor their functional properties for food packaging applications. The incorporation of hydroxyapatite-rich residues contributes to the full valorization of fish processing by-products, supporting the development of sustainable and biodegradable functional materials within a circular economy approach.

Postharvest fruit losses significantly impact producers and distributors. Although synthetic preservatives mitigate these losses, consumer safety concerns and regulatory restrictions drive interest in alternative approaches. Propolis, rich in polyphenols, exhibits antioxidant and antimicrobial activities, making it a promising natural strategy to preserve fruit quality. This study aimed to evaluate the effects of the pre- and postharvest applications of Portuguese propolis extracts on the preservation of postharvest quality of ‘Rocha’ pear, an exclusively Portuguese variety of major economic importance. Treatments were applied by spraying the fruits one month before and at harvest. After five months of cold storage, the main quality parameters, phenolic content, antioxidant capacity, physiological disorders, and microbial contamination were assessed. The results showed that the application of propolis extract, either 30 days before or immediately after harvest, reduces the total microbiological load on the fruit’s epidermis (~1-log to 2-log reduction, after treatment). Moreover, the treatment enhanced the preservation of key quality attributes, including a reduction in water loss of up to 44%, a 13–33% decrease in firmness loss relative to the control, and a lower incidence of physiological disorders during postharvest storage. Furthermore, the application of propolis can enhance the production of fruits with higher levels of bioactive compounds, while also adding value to a bee product that is often underappreciated by most beekeepers.

The overuse of nonrenewable resources has motivated intensive research and the development of new types of green bio-based and degradable feedstocks derived from natural sources, such as cellulose derivates, also in nanoforms. The inclusion of such nanoparticles in bio-based polymers with the aim of providing reinforcement is a trend, which, when associated with the incorporation active compounds, creates active packaging suitable for the packaging of highly perishable food, thus contributing to the product’s shelf-life extension. Chitosan (Ch)/sage essential oil (SEO) bionanocomposite reinforced with nanocrystalline cellulose (CNC) was cast as active packaging for the preservation of fresh poultry meat. Meat samples were wrapped in different bioplastics (pristine chitosan, chitosan with commercial CNC, chitosan with CNC obtained from three different lignocellulosic crops, giant reed (G), kenaf (K), and miscanthus (M), chitosan with SEO, and chitosan with SEO and CNC), while unwrapped samples were tested as the control. Periodically, samples were evaluated in terms of their physicochemical properties and microbial growth. Additionally, bionanocomposites were also evaluated in terms of their in situ antimicrobial properties, as well as migration toward food simulants. Meat samples protected with bionanocomposites showed lower levels of microbiological growth (2–3 logs lower than control) and lipid oxidation (20–30% lower than in control), over time. This was attributed to the intrinsic antimicrobial capacity of chitosan and the high oxygen barrier properties of the films resulting from the CNC inclusion. The SEO incorporation did not significantly improve the material’s antimicrobial and antioxidant activity yet interfered directly with the meat’s color as it migrated to its surface. In the in vitro assays, all bionanocomposites demonstrated good antimicrobial activity against B. cereus (reduction of ~8.2 log) and Salmonella Choleraesuis (reduction of ~5–6 log). Through the in vitro migration assay, it was verified that the SEO release rate of phenolic compounds to ethanol 50% (dairy products simulate) was higher than to ethanol 95% (fatty food simulate). Furthermore, these migration tests proved that nanocellulose was capable of delaying SEO migration, thus reducing the negative effect on the meat’s color and the pro-oxidant activity recorded in TBARS. It was concluded that the tested chitosan/nanocellulose bionanocomposites increased the shelf life of fresh poultry meat.

Background/Objectives: Periploca chevalieri Browicz (Apocynaceae), an endemic species of the Cabo Verde archipelago, is commonly used in traditional medicine for the treatment of diabetes. The aim of this study was to characterize the chemical profiles of the aqueous and hydroethanolic (70%) extracts of the P. chevalieri dried aerial parts (PcAE and PcEE) and evaluate their potential to modulate postprandial glycemia and inhibit key carbohydrate-hydrolyzing enzymes. Methods: The chemical characterization was performed by LC/UV-DAD-ESI/MS/MS. An in vivo evaluation of postprandial glycemia modulation was conducted on healthy CD1 mice submitted to an oral sucrose tolerance test. In vitro enzymatic inhibition was performed for the α-amylase, α-glucosidase, and DPP4 enzymes. Additionally, antioxidant and antiglycation activities were also assessed. Results: Phenolic acid derivatives, flavanols, proanthocyanidins, and flavonols were the major classes of secondary metabolites identified. PcEE at 170 mg/kg of body weight significantly (p < 0.05) reduced the postprandial glycemia peak in CD1 mice submitted to sucrose overload. Regarding the enzymatic inhibition, both extracts showed concentration-dependent inhibitory potential against the α-amylase, α-glucosidase, and DPP4 enzymes. Both extracts inhibited α-glucosidase more effectively than acarbose. Conclusions: The obtained results supports the traditional use of P. chevalieri and suggest the potential for further pharmacological investigation.

Canning is an excellent solution to provide convenient, affordable, nutritious, and safe seafood with a long shelf life. However, many canned products use tuna, sardines, and Atlantic chub mackerel, species that raise sustainability concerns and whose overuse can put additional pressure on them. Hence, this study aimed to i) develop and assess a nutritious and sustainable canned meal prototype using the Atlantic horse mackerel (Trachurus trachurus) (whose EU allowable-catch amounts have increased, particularly, in Iberian waters) and vegetables in light brine in terms of stability, sterility, and physicochemical and sensory properties over a 4-month period at room temperature and ii) evaluate its nutritional contribution for different population groups. After preparation, the meal was stored for one month at ≈20 °C and ≈40 °C (to simulate the 4 months). Although the pH was not stable, the meal was considered commercially sterile according to the challenge accelerated tests. Moreover, aging did not significantly affect the meal’s physicochemical and sensory properties. This innovative meal prototype can be claimed to be “low-fat”, “reduced in NaCl/Na”, a “source of protein, phosphorus, iron, selenium and vitamin D”, and “high in vitamin B12”. It proved to be both nutritious and appealing for consumption, with potential to be scaled up.

Biotechnological active peptides are gaining interest in the cosmetics industry due to their antimicrobial, anti-inflammatory, antioxidant, and anti-collagenase (ACE) effects, as well as wound healing properties, making them suitable for cosmetic formulations. The antimicrobial activity of peptides (2–10 kDa) secreted by Saccharomyces cerevisiae Ethanol-Red was evaluated against dermal pathogens using broth microdilution and challenge tests. ACE was assessed using a collagenase activity colorimetric assay, antioxidant activity via spectrophotometric monitoring of nitrotetrazolium blue chloride (NBT) reduction, and anti-inflammatory effects by quantifying TNF-α mRNA in lipopolysaccharides (LPS)-exposed dermal fibroblasts. Wound healing assays involved human fibroblasts, endothelial cells, and dermal keratinocytes. The peptides (2–10 kDa) exhibited antimicrobial activity against 10 dermal pathogens, with the Minimum Inhibitory Concentrations (MICs) ranging from 125 µg/mL for Staphylococcus aureus to 1000 µg/mL for Candida albicans and Streptococcus pyogenes. In the challenge test, peptides at their MICs reduced microbial counts significantly, fulfilling ISO 11930:2019 standards, except against Aspergillus brasiliensis. The peptides combined with Microcare^Ⓡ SB showed synergy, particularly against C. albicans and A. brasilensis. In vitro, the peptides inhibited collagenase activity by 41.8% and 94.5% at 250 and 1000 µg/mL, respectively, and demonstrated antioxidant capacity. Pre-incubation with peptides decreased TNF-α expression in fibroblasts, indicating anti-inflammatory effects. The peptides do not show to promote or inhibit the angiogenesis of endothelial cells, but are able to attenuate fibrosis, scar formation, and chronic inflammation during the final phases of the wound healing process. The peptides showed antimicrobial, antioxidant, ACE, and anti-inflammatory properties, highlighting their potential as multifunctional bioactive ingredients in skincare, warranting further optimization and exploration in cosmetic applications.

This study aims to develop purple-coloured polymeric coatings using natural anthocyanin and desoxyanthocianidins (3-DXA) colourants for application to chocolate almonds. The objective is to achieve a stable and uniform colour formulation throughout processing and storage, enhancing the appearance and durability of the almonds to appeal to health-conscious consumers and align with market demands. Plant materials like sweet potato pulp, sweet potato peel, radish peel, black carrot, and sorghum were employed to obtain the desired purple hue. Anthocyanidins and 3-DXA were extracted from the matrices using solvent extraction and ultrasound-assisted methods at different pH values. High-performance liquid chromatography with diode array detection (HPLC-DAD) and high-resolution tandem mass spectrometry (HRMS/MS) were used to identify the compounds in the extracts. The highest antioxidant capacities, as measured by the DPPH^• and FRAP methods, were observed in purple sweet potato and dye factory extracts, respectively; meanwhile, sorghum extract inhibited both α-amylase and α-glucosidase, indicating its potential for managing postprandial hyperglycemia and type 2 diabetes. The degradation kinetics of coloured coatings in sugar syrup formulations with anthocyanins and 3-DXA revealed that locust bean gum offered the best colour stabilization for plant extracts, with sorghum extracts showing the highest and black carrot extracts the lowest colour variation when coated with Arabic gum. Sweet potato pulp extracts exhibited less colour variation in sugar pastes, both with and without blue spirulina dye, compared to factory dye, highlighting their potential as a more stable and suitable alternative for colouring purple almonds, particularly over a five-month storage period. This study supports sustainable practices in the confectionery industry while aligning with consumer preferences for healthier and environmentally friendly products.

The continuous monitoring of Hg2+ levels in aqueous environments is crucial to assess a potential indication of methylmercury contamination via bacterial conversion, yet existing methods often require extensive sample treatment, expensive equipment, and transportation to a specialized facility. To mitigate this issue, this study introduces the synthesis and application of three naphthalimide-based compounds with significant fluorescent and solvatochromic behaviour (C1, C2 and C3) for the detection of mercury ions, with an inherent associated antibacterial activity, creating a dual-functionality material. The incorporation of these compounds into polymers, such as polyvinyl chloride (PVC), poly (methyl methacrylate-co-methacrylic acid) (PUMA), and starch, allowed for the development of solid-support sensors/surfaces with a strong antibacterial profile, highlighting the inherent dual-functionality of the compounds. Most interestingly, the C2-doped starch biopolymer allowed for the detection of Hg2+ ions at concentrations as low as 2 ppm in an aqueous environment through a rapid, on-site evaluation without the need for sample treatment. This biopolymer was constructed following a sustainable, green-chemistry-oriented, temperature-dependent water/starch synthetic route, without the addition of plasticizers, and without any associated ecotoxicity. The study promotes the use of sustainable methods for environmental monitoring and antibacterial applications, advancing material science to offer effective, accessible, and eco-friendly solutions for detecting and mitigating mercury pollution and bacterial contaminations, enhancing environmental and health safety.