Percorrer por autor "Fonseca, Mariana"
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- Achieving efficient viability of akkermansia muciniphila during aerobic storage and gastrointestinal passage through calcium-alginate encapsulationPublication . Machado, Daniela; Fonseca, Mariana; Vedor, Rita; Barbosa, Joana Cristina; Gomes, Ana Maria
- Aggregation properties of probiotic strains under aerobic and anaerobic conditionsPublication . Machado, Daniela; Andrade, José Carlos; Barbosa, Joana Cristina; Costa, Francisca; Fonseca, Mariana; Almeida, Diana; Freitas, Ana Cristina; Gomes, Ana Maria
- Aggregation properties of probiotic strains under aerobic and anaerobic conditionsPublication . Machado, Daniela; Andrade, José Carlos; Barbosa, Joana Cristina; Costa, Francisca; Fonseca, Mariana; Almeida, Diana; Freitas, Ana Cristina; Gomes, Ana Maria
- Akkermansia muciniphila encapsulated in calcium-alginate hydrogelated matrix: viability and stability over aerobic storage and simulated gastrointestinal conditionsPublication . Machado, Daniela; Fonseca, Mariana; Vedor, Rita; Sousa, Sérgio; Barbosa, Joana Cristina; Gomes, Ana MariaAkkermansia muciniphila is considered a next-generation probiotic to be incorporated in new food and pharmaceutical formulations. Effective delivery systems are required to ensure high probiotic viability and stability during product manufacture, shelf-life, and post-consumption, namely, throughout digestion. Hydrogelated matrices have demonstrated promising potential in this dominion. Hence, this work aimed to evaluate the effect of a calcium-alginate hydrogelated matrix on A. muciniphila viability during 28-days refrigerated aerobic storage and when exposed to simulated gastrointestinal conditions, in comparison with that of free cells. Akkermansia muciniphila was successfully encapsulated in the calcium-alginate matrix via extrusion (60% encapsulation yield). Furthermore, encapsulated A. muciniphila exhibited high stability (a loss in viability lower than 0.2 log-cycle) after 28-days of refrigerated aerobic storage, maintaining its viability around 108 CFU/g. Prominently, as the storage time increased, encapsulated A. muciniphila revealed higher viability and stability regarding in vitro gastrointestinal conditions than free cells. This suggests that this encapsulation method may attenuate the detrimental effects of prolonged aerobic storage with a subsequent gastrointestinal passage. In conclusion, encapsulation via extrusion using a calciumalginate hydrogelated matrix seems to be a promising and adequate strategy for safeguarding A. muciniphila from adverse conditions encountered during refrigerated aerobic storage and when exposed to the gastrointestinal passage.
- Avaliação do potencial prebiótico das “farinhas” de batata-doce e bagaço de pêraPublication . Soares, Inês; Vedor, Rita; Fonseca, Mariana; Pinto, Jorge; Machado, Daniela; Gomes, Ana MariaO desperdício alimentar, uma forma de biowaste comum a nível global, é um dos maiores desafios de sustentabilidade que a indústria alimentar enfrenta. A indústria de frutas e hortícolas destaca-se neste contexto, sendo responsável por 25 a 30% do total, incluindo resíduos como cascas, sementes e bagaço [1,2]. A valorização deste tipo de resíduos constitui uma estratégia que visa transformar estes em produtos de valor acrescentado. Concretamente, as farinhas de bagaço de pêra e de batata-doce mantêm altos níveis de nutrientes e compostos bioativos, criando oportunidades para o desenvolvimento de alimentos funcionais promotores de saúde e bem-estar [3,4]. Este estudo visou investigar o potencial prebiótico destas farinhas, avaliando a sua capacidade de estimular o crescimento e a atividade metabólica de duas estirpes probióticas, nomeadamente Lacticaseibacillus rhamnosus GG (LGG) e Bifidobacterium longum subsp. infantis DSM 20088 (B.infantis). A seleção destas estirpes deve-se às suas reconhecidas propriedades benéficas para a saúde intestinal e à capacidade de fermentar diferentes tipos de substratos. A metodologia utilizou o meio Man-Rogosa- Sharpe (MRS) como base, com modificações para criar diferentes condições de cultivo, nomeadamente: um controlo negativo (MRS sem glucose), um controlo positivo (MRS com 2% de glucose), um controlo prebiótico (MRS com 2% de frutooligossacarídeos) e meios com 2% e 6% de farinhas de batata-doce e de bagaço de pêra. A LGG foi cultivada em condições aeróbicas, enquanto a B. infantis manteve- se em anaerobiose, ambas a 37ºC. As amostras foram colhidas às 0, 3, 6, 10 e 24 horas de incubação para quantificação de unidades formadoras de colónias (UFC) e medição do pH, avaliando o crescimento e metabolismo bacteriano, respetivamente. Os resultados demonstraram que, no geral, a farinha de bagaço de pêra a 6% e a farinha de batata-doce, nas concentrações de 2 e 6%, promoveram o crescimento de B. infantis de forma equivalente ou ligeiramente superior à glucose (entre 3 a 6 x 10 9 UFC/mL). Por outro lado, as concentrações mais elevadas (6%) de farinha de batata- doce e de bagaço de pêra favoreceram o crescimento de L. rhamnosus GG de forma mais significativa do que a glucose (+ 0.5 ciclo log). A sua elevada capacidade de estimular o crescimento e o metabolismo de bactérias probióticas revela um potencial prebiótico para estas farinhas e destaca a sua aplicação como potenciais ingredientes funcionais para o desenvolvimento de produtos alimentares sustentáveis, com valor acrescentado e potencial benefício para a saúde humana.
- Can a functional cheese spread incorporating Akkermansia muciniphila deliver beneficial physicochemical and biological properties while enhancing probiotic stability and viability during aerobic storage and in vitro digestion?Publication . Fonseca, Mariana; Vedor, Rita; Barbosa, Joana C.; Gomes, Ana Maria; Machado, DanielaIn the present study, next generation probiotic Akkermansia muciniphila was incorporated into a dairy matrix containing Portuguese whey cheese and Greek-style yoghurt in a proportion of 3.5:1, respectively. Subsequently, this innovative food was characterized in terms of microbiological and physicochemical parameters, total phenolic content and antioxidant, antidiabetic, and antihypertensive activities, as well as its protective effect on A. muciniphila viability during 21 d of refrigerated aerobic storage and when subjected to simulated gastrointestinal passage. The probiotic cheese spread displayed high microbiological quality, low total phenolic content (0.36 mg gallic acid equivalents/g of dried cheese) and interesting biological activities, including antidiabetic (98.10% α-glucosidase inhibition) and antihypertensive (49.18% angiotensin converting enzyme inhibition). Simultaneously, this food ensured a high A. muciniphila viability (>108 CFU/g) during 21 d of refrigerated aerobic storage with subsequent in vitro digestion. Additionally, this probiotic cheese presented a similar profile in terms of texture, color, water activity and pH when compared to the cheese control (without A. muciniphila), suggesting a potentially high acceptance among consumers. In conclusion, the developed cheese spread seems to be a promising and suitable food vector to safeguard A. muciniphila viability during refrigerated aerobic storage for at least 21 d with subsequent gastrointestinal passage.
- Development and characterization of a cheese spread incorporating the next generation probiotic akkermansia muciniphilaPublication . Fonseca, Mariana; Vedor, Rita; Machado, Daniela; Barbosa, Joana; Gomes, Ana
- Encapsulation of Akkermansia muciniphila in calcium-alginate matrix: a live biotherapeutic strategy for gut microbiota modulation and intestinal infection mitigationPublication . Machado, Daniela; Vedor, Rita; Fonseca, Mariana; Sousa, Sérgio; Barbosa, Joana Cristina; Carvalho, Nelson Mota de; Costa, Célia Maria; Madureira, Ana Raquel; Gomes, Ana MariaObjective: Akkermansia muciniphila is a next-generation probiotic recognized for improving gut barrier function and metabolic health. However, ensuring its viability during processing, storage, and gastrointestinal transit remains a challenge. This study investigated calcium-alginate encapsulation as a strategy for enhancing the stability of A. muciniphila during refrigerated aerobic storage and gastrointestinal passage as well as biological validation in an in vitro fecal model. Methods: A. muciniphila was encapsulated using an extrusion technique with 2% (m/v) sodium alginate and 4% (m/v) calcium chloride. Viability of free and encapsulated cells was assessed over 28-days of refrigerated aerobic storage. Gastrointestinal stability was evaluated using the INFOGEST protocol. In vitro colonic fermentation was conducted in healthy and Escherichia coli O157:H7-infected fecal samples. Microbial composition was analyzed via metagenomic sequencing, while microbial metabolism was assessed by ammonia quantification and short- chain fatty acids (SCFA) profile analysis. Results: Encapsulation achieved a 60% yield and preserved high probiotic viability (at levels around 8-log CFU/g) during 28- days of storage. Moreover, encapsulated cells exhibited higher survival when exposed to gastrointestinal conditions compared to free cells. In fecal fermentation assays, encapsulated A. muciniphila enhanced microbial diversity, reduced Escherichia genus abundance, and modulated SCFA profile. Furthermore, an increasing trend in ammonia production until the 30-hour mark, followed by a decline suggests potential ammonia assimilation by the probiotic. Conclusions: Calcium-alginate encapsulation is a promising delivery strategy to improve the viability and functionality of A. muciniphila, supporting its use as a live biotherapeutic agent for modulating gut microbiota and intestinal infections mitigation.
- From tradition to innovation: enhancing a ready-to eat spinach mash with algaePublication . Barbosa, Joana Cristina; Fonseca, Mariana; Barracosa, Rita; Magalhães, Inês; Correia, Daniela; Grilo, Beatriz; Pedroso, Verónica; Gomes, Ana M.Objective: To enhance the nutritional profile of a traditional Portuguese dish, esparregado, this project explored the incorporation of algae and microalgae as sustainable and health- promoting ingredients. Methods: A conventional esparregado recipe made with spinach was reformulated by incorporating algae-based ingredients. Three prototypes were developed: (1) with 10% (w/w) Ulva rigida; (2) with 10% (w/w) Chlorella vulgaris; and (3) combining 10% Ulva rigida with 6% Chlorella vulgaris. These were produced at semi-industrial scale in partnership with an industrial collaborator. Sensory and nutritional analyses were conducted to evaluate organoleptic properties and validate nutritional claims. Results: Prototype (1) was rich in fibre, vitamin B12, magnesium, iodine, and iron; prototype (2) was high in protein and zinc; and prototype (3) combined the nutritional benefits of both algae. Sensory evaluation by a trained panel indicated that the addition of algae did not adversely impact the organoleptic properties of the product, preserving its traditional sensory appeal. Conclusions: Incorporating algae and microalgae into esparregado is a promising strategy to improve its nutritional value without compromising taste or texture. This sustainable reformulation offers consumers a familiar dish with enhanced health benefits, and the combination of Ulva rigida and Chlorella vulgaris emerged as the most balanced and attractive option.
- Reinventing smoothies with microalgae: enhancing nutrition and antioxidant capacity for an innovative functional beveragePublication . Barbosa, Joana Cristina; Fonseca, Mariana; Helou, Pelega; Barracosa, Rita; Magalhães, Inês; Correia, Daniela; Grilo, Beatriz; Pedroso, Verónica; Gomes, Ana M.Objective: This study aimed to develop and assess microalgae- enriched smoothies as stable, nutrient-rich, and sustainable functional beverages. The focus was on enhancing nutritional value and bioactive properties using two sustainably cultivated species: Chlorella vulgaris and Limnospira platensis (Spirulina). Methods: Two smoothie formulations were developed: SCv (with Chlorella vulgaris) and SSp (with Spirulina), each produced in frozen and freeze-dried formats. Products were stored for 56 days, with biweekly analyses of physicochemical properties including pH, color, and water activity. Nutritional content (macro- and micronutrients) and bioactivity—measured through total phenolic content (TPC), and ORAC, and ABTS antioxidant assays—were also evaluated. Results: Freeze-dried smoothies demonstrated greater stability over the 56-day period, with minimal changes in physicochemical properties. SSp showed higher antioxidant activity than SCv across all assays (4529.5 vs 2995.5 ?mol Trolox Equivalent /L), while both remained modest sources of polyphenols (0.224 and 0.132 mg GAE/mL, respectively). In terms of nutritional claims, SCv qualified as a source of protein (2.5 g /100g of product), and SSp met the criteria for a high-protein product (6.6 g /100g of product), with the clear protein apport provided by microalgae, thus supporting their classification as functional beverages. Conclusions: Microalgae-enriched smoothies, particularly in freeze-dried format, offer a promising approach to delivering stable, nutrient-dense, and bioactive food products. The combination of enhanced protein content and antioxidant potential, especially in Spirulina-containing formulations, supports their relevance for health-conscious and sustainability- driven consumers.