Biblioteca Digital do IPB
Repositório de Publicações do Instituto Politécnico de Bragança
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Solid Dispersions as a Tool for Innovation in the Food Industry: A Path From Pharma to Food
Publication . Rezende, Stephany; Santamaria-Echart, Arantzazu; Dias, Madalena M.; Barreiro, Filomena
Solid dispersion (SD) is a technique used to improve the solubility of poorly water-soluble compounds by dispersing them in a solid water-friendly carrier. Current trends indicate that natural-based alternatives are increasingly replacing synthetic carriers, benefiting the pharmaceutical industry, where they were first adopted, and paving the way for broader use in nutraceuticals and food applications, as regulations and consumer preferences drive the adoption of eco-friendly alternatives. In the food industry, SDs can address key challenges, such as enhancing water compatibility and stabilizing sensitive compounds, thereby facilitating the effective use of natural-based ingredients. Exploring natural carriers enables SDs to align with food industry priorities, enabling the development of functional ingredients, stable natural colorants, products with increased flavor retention, innovative packaging materials, and healthier, structured food analogues through Pickering emulsion technology. In this context, the review examines the path of SDs from pharma to food, beginning with a detailed examination of SD systems using both synthetic and natural carriers across the pharmaceutical, nutraceutical, and food sectors. The review concludes with an in-depth discussion of emerging applications in the food industry, highlighting the potential of SDs to address formulation challenges and to foster sustainable, consumer-oriented innovations in modern food systems. To advance SD applications in food systems, future research should integrate sensory evaluation and address technical, regulatory, and formulation-performance gaps to ensure consumer-acceptable, high-quality innovations.
Removal of metformin from aquatic matrices using cork-based adsorbents
Publication . Morizaki, Gabrielle Tokawa; Gomes, Maria Carolina Sérgi; Queiroz, Ana; Brito, Paulo; Ribeiro, António E.
Metformin is considered an emerging micropollutant, belonging to the pharmaceutical class, and is widely used in the treatment of type 2 diabetes. Due to its incomplete metabolism and extensive prescription for chronic disease management, it has been frequently detected in aquatic environments. Even at trace concentrations, it may cause endocrine disruptions in aquatic biota and lead to the formation of toxic byproducts during water treatment.1,2 In this context, the present study aimed to evaluate the efficiency of metformin removal from aqueous matrices through the adsorption process, using activated carbons produced from cork residues. The methodology involved the preparation of the adsorbents via physical activation (CF) and chemical activation using potassium hydroxide (KOH) (CQ), followed by characterization in terms of carbonization yield, moisture and ash content, point of zero charge (pHPZC), presence of acidic and basic surface functional groups, and Fourier-transform infrared spectroscopy (FTIR). Metformin quantification was carried out by high-performance liquid chromatography with diode array detection (HPLC-DAD). Studies on drug removal, adsorption kinetics, activation energy estimation, and evaluation of operational parameters influencing the process, such as adsorbent dosage, pH, and initial metformin concentration, were conducted. The results demonstrated that the type of activation applied to each carbon significantly influenced the physicochemical properties of the materials, as well as their adsorption performance. According to the kinetic studies, adsorption equilibrium was reached within the first minutes for CQ, while for CF it was more gradual. In equilibrium studies, the Freundlich and Langmuir isotherm models were applied. For CF, both models showed a good fit, with a predominance of the Freundlich model, indicating a slightly heterogeneous surface and favorable adsorption. For CQ, the Langmuir model provided a better fit, with a high maximum adsorption capacity, suggesting monolayer adsorption on a more homogeneous surface.3,4
From the study carried out, the activated carbons produced from cork residues demonstrated high performance as promising materials for the removal of metformin in aqueous media, particularly those obtained through chemical activation, achieving a removal efficiency of approximately 99.0% under optimized alkaline pH conditions (pH 11). The use of this residue as a raw material highlights the potential of renewable-origin adsorbents in water treatment processes, contributing to the valorization of an abundant by-product in Portugal and to the development of more environmentally sustainable solutions, in line with the principles of a circular economy.
Uso de membranas incorporadas com cortiça para a purificação de biodiesel de óleo residual
Publication . Romansina, Bruna Clara; Brito, Paulo; Paschoal, Sirlei M.; Gomes, Maria Carolina Sérgi
O biodiesel vem ganhando destaque no mundo por possuir matéria-prima renovável, além de ser menos poluente que os combustíveis fósseis. Após a transesterificação, é necessária a separação e purificação dos ésteres, sendo empregadas lavagens aquosas para remover o glicerol. Porém, este processo convencional requer um alto volume de água. O objetivo deste trabalho foi avaliar o processo de separação utilizando membranas poliméricas funcionalizadas com cortiça como alternativa na purificação de biodiesel. O biodiesel foi produzido por transesterificação etílica utilizando óleo de algodão residual e NaOH como catalisador. As membranas foram produzidas pelo método de inversão de fases empregando polietersulfona como polímero, polivinilpirrolidona como copolímero, dimetilacinamida como solvente e cortiça como aditivo. As membranas foram caracterizadas em termos de permeabilidade hidráulica e MEV. O processo de separação foi realizado em um módulo de membranas e avaliou-se a filtração em duas fases distintas da produção do biodiesel. A primeira fase após a transesterificação e a segunda foi após a decantação da mistura reacional, utilizando a fase leve rica em ésteres. A menor concentração de glicerol obtida no permeado foi 0,097 ± 0,006%, na filtração da fase leve contendo os ésteres, representando uma retenção do glicerol pela membrana foi de 99,65%.
Industrial effluent remediation using aquatic mosses: an effective biosorption approach
Publication . Martins, Ramiro
Heavy metals in industrial wastewater pose significant environmental and public health threats. This study explored the use of the aquatic moss Fontinalis antipyretica as a natural biosorbent to eliminate cadmium (Cd²⁺) and lead (Pb²⁺) from simulated wastewater. The study assessed the impact of crucial factors such as initial pH, contact time, and metal ion concentration, utilizing a sorbent dose of 2 g L⁻¹. Optimal biosorption occurred at pH levels ranging from 4.0 to 6.0, achieving a maximum uptake capacity of 4.8 mg g⁻¹ for both metals at an initial 10 mg L⁻¹ concentration. At a concentration of 100 mg L⁻¹, the removal efficiency of Pb²⁺ exceeded 78%, demonstrating a stronger affinity for Pb. Among the kinetic models tested, the pseudo-second-order model best fit the experimental data (R² = 0.999), indicating that chemisorption was a key mechanism in the process. These results highlight the potential of Fontinalis antipyretica as an effective, cost-efficient, and environment-friendly method for treating metal-laden industrial effluents
Valorização de resíduos de biomassa para a remoção de estrogénios em matrizes aquosas
Publication . Exposto, Bruno Marques; Queiroz, Ana; Ribeiro, António E.; Brito, Paulo
Os estrogénios são substâncias consideradas disruptores endócrinos, ou seja, têm a capacidade de desregular o sistema endócrino dos seres vivos. Estes compostos podem ocorrer naturalmente, como a estrona (E1) e o estradiol (E2), ou na forma sintetizada, como o etinilestradiol (EE2) [1]. Os efeitos nocivos destes fármacos manifestam-se mesmo em baixas concentrações (µg/L ou ng/L), sendo considerados como micropoluentes [1]. Por outro lado, estas substâncias são consideradas poluentes emergentes devido à sua elevada persistência, sendo encontradas em concentrações sucessivamente crescentes no ambiente [2].