Raquel Fernandes

Mrs. Raquel Fernandes

orcid

Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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14 April 2023 in Pharmaceuticals
Verified
Journal Article
Open access
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RFRaquel Fernandes
Raquel Fernandes
Joana CamposJoana Campos
Joana Campos
MSMónica Serra
Mónica Serra
JFJavier Fidalgo
Javier Fidalgo
Hugo AlmeidaHugo Almeida
Hugo Almeida
Ana Novo BarrosAna Novo Barros
Ana Novo Barros
Large-scale production of microalgae and their bioactive compounds has steadily increased in response to global demand for natural compounds. Spirulina, in particular, has been used due to its high nutritional value, especially its high protein content. Promising biological functions have been associated with Spirulina extracts, mainly related to its high value added blue pigment, phycocyanin. Phycocyanin is used in several industries such as food, cosmetics, and pharmaceuticals, which increases its market value. Due to the worldwide interest and the need to replace synthetic compounds with natural ones, efforts have been made to optimize large-scale production processes and maintain phycocyanin stability, which is a highly unstable protein. The aim of this review is to update the scientific knowledge on phycocyanin applications and to describe the reported production, extraction, and purification methods, including the main physical and chemical parameters that may affect the purity, recovery, and stability of phycocyanin. By implementing different techniques such as complete cell disruption, extraction at temperatures below 45 °C and a pH of 5.5–6.0, purification through ammonium sulfate, and filtration and chromatography, both the purity and stability of phycocyanin have been significantly improved. Moreover, the use of saccharides, crosslinkers, or natural polymers as preservatives has contributed to the increased market value of phycocyanin.

24 November 2023 in Biomedicines
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Journal Article
Open access
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RFRaquel Fernandes
Raquel Fernandes
Cátia CostaCátia Costa
Cátia Costa
Rúben FernandesRúben Fernandes
Rúben Fernandes
Ana Novo BarrosAna Novo Barros
Ana Novo Barros
Prostate cancer (PCa) remains a significant global health concern, being a major cause of cancer morbidity and mortality worldwide. Furthermore, profound understanding of the disease is needed. Prostate inflammation caused by external or genetic factors is a central player in prostate carcinogenesis. However, the mechanisms underlying inflammation-driven PCa remain poorly understood. This review dissects the diagnosis methods for PCa and the pathophysiological mechanisms underlying the disease, clarifying the dynamic interplay between inflammation and leukocytes in promoting tumour development and spread. It provides updates on recent advances in elucidating and treating prostate carcinogenesis, and opens new insights for the use of bioactive compounds in PCa. Polyphenols, with their noteworthy antioxidant and anti-inflammatory properties, along with their synergistic potential when combined with conventional treatments, offer promising prospects for innovative therapeutic strategies. Evidence from the use of polyphenols and polyphenol-based nanoparticles in PCa revealed their positive effects in controlling tumour growth, proliferation, and metastasis. By consolidating the diverse features of PCa research, this review aims to contribute to increased understanding of the disease and stimulate further research into the role of polyphenols and polyphenol-based nanoparticles in its management.

24 January 2023 in Cells
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Journal Article
Open access
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SLSofia Libório-Ramos
Sofia Libório-Ramos
CBCatarina Barbosa-Matos
Catarina Barbosa-Matos
RFRaquel Fernandes
Raquel Fernandes
CPCaroline Borges Pereira
Caroline Borges Pereira
SCSandra Costa
Sandra Costa
A progressive fibrosing phenotype is critical in several lung diseases. It is irreversible and associated with early patient mortality. Growing evidence has revealed pulmonary macrophages’ role as modulators of the fibrotic processes. The proportion, phenotype, and function of alveolar (AM) and interstitial macrophages (IM) at the early stages of bleomycin-induced pulmonary fibrosis have not been clearly described. In this way, our study aimed to characterize these macrophage populations and investigate the effect on fibroblast activation. C57BL/6 mice were intratracheally injected with bleomycin and were sacrificed at day 3, 5, and 7 for the performance of flow cytometry and fluorescent-activated cell sorting analysis for protein and gene expression quantification. After bleomycin administration, the proportion of IM was significantly higher than that of AM, which showed a decay during the inflammatory phase, and peaked at day 7. At day 7 of the inflammatory phase, AM started shifting their phenotype from M1-like towards M2, while IM showed a M2-like phenotype. Conditioned medium derived from IM sorted at day 7 induced fibroblast activation and differentiation in myofibroblasts in vitro. Our findings indicate that IM are the largest macrophage population at the early stages of experimental pulmonary fibrosis and are secreted mediators able to activate fibroblasts, pointing to macrophage modulation as a potential therapeutic strategy to restrain progressive fibrosing lung disorders.

18 November 2024 in Molecules
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Journal Article
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Rui Dias-CostaRui Dias-Costa
Rui Dias-Costa
CMConcepción Medrano-Padial
Concepción Medrano-Padial
RFRaquel Fernandes
Raquel Fernandes
RDRaul Dominguez-Perles
Raul Dominguez-Perles
Irene GouvinhasIrene Gouvinhas
Irene Gouvinhas
Ana Novo BarrosAna Novo Barros
Ana Novo Barros
Grape (Vitis vinifera L.) stems, a by-product of winemaking, possess significant potential value due to their rich polyphenolic composition, which allows their exploitation for cosmetic and pharmaceutical applications. This presents a promising opportunity for valorisation aimed at developing innovative products with potential health-promoting effects. In this study, the polyphenolic profile of extracts from grape stems of seven white grape varieties was determined using spectrophotometric and chromatographic methods, specifically high-performance liquid chromatography coupled with a photodiode array detector and electrospray ionization multi-stage mass spectrometry (HPLC-PDA-ESI-MSn), as well as on their ferric-reducing antioxidant power (FRAP) and radical scavenging capacity, using 2,2-diphenyl-1-picrylhydrazyl (DPPH●) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS●+) radicals. This study also evaluated the anti-aging activity and skin depigmenting activity of these extracts. These findings revealed a diverse polyphenolic profile, encompassing proanthocyanidins and catechin derivatives (PCDs), phenolic acids, and flavonols. Among the varieties studied, ‘Códega do Larinho’ exhibited the highest concentrations of six distinct polyphenols and the highest total phenolic content. It also demonstrated the highest results for antioxidant capacity and elastase and tyrosinase inhibition. Pearson’s correlation analysis showed a significant positive correlation between certain PCDs with both FRAP and DPPH assays, as well as between the identified flavonols and anti-elastase activity. These results underscore the potential health benefits of grape stem extracts and emphasize the importance of their polyphenolic composition in enhancing antioxidant and anti-aging properties, thus supporting their application in different industries.

6 March 2024 in Antioxidants
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Journal Article
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Jorge Gomes Lopes BarrosJorge Gomes Lopes Barros
Jorge Gomes Lopes Barros
RFRaquel Fernandes
Raquel Fernandes
AAAna Santos Abraão
Ana Santos Abraão
Rui Dias-CostaRui Dias-Costa
Rui Dias-Costa
Alfredo AiresAlfredo Aires
Alfredo Aires
Ana Novo BarrosAna Novo Barros
Ana Novo Barros
The historical use of plants as sources of natural compounds has persisted over time. Increasing the intake of bioactive substances shows significant potential for promoting overall well-being and health. This study delves into the pigments, phenolic composition, and profile, along with antioxidant properties, of leaf extracts rich in bioactives from plants in the Azores region, contributing to sustainable primary food production. Analyses encompassed chlorophylls, carotenoids, total phenols, ortho-diphenols, and flavonoids, as well as antioxidant capacity assessment, polyphenolic profiling, and quantification. Psidium guajava L. and Smallanthus sonchifolius (Poepp.) H.Rob. exhibited elevated chlorophyll content, while Colocasia esculenta (L.) Schott displayed the highest carotenoid levels. Annona cherimola Mill., Eriobotrya japonica (Thunb.) Lindl, and Psidium guajava L. demonstrated pronounced total phenols, ortho-diphenols, and flavonoids. These findings align with heightened antioxidant capacity. HPLC–DAD (high-performance liquid chromatography with diode-array detection) characterization unveiled elevated hydroxycinnamic acids in E. japonica and Ipomea batatas (L.) Lam. compared to A. cherimola Mill., while C. esculenta exhibited increased flavone content. Among the quantified compounds, flavonols were the ones that predominantly demonstrated contribution to the antioxidant capacity of these leaves. This research highlights Azorean leaf plants’ antioxidant potential, fostering natural product development for better health.

4 February 2025 in Food Chemistry: X
Verified
Journal Article
Open access
RFRaquel Fernandes
Raquel Fernandes
CMConcepción Medrano-Padial
Concepción Medrano-Padial
Rui Dias-CostaRui Dias-Costa
Rui Dias-Costa
RDRaúl Domínguez-Perles
Raúl Domínguez-Perles
CBCláudia Botelho
Cláudia Botelho
Ana Novo BarrosAna Novo Barros
Ana Novo Barros
The Douro Demarcated Region's winery industry produces million tonnes of by-products annually, making their reuse essential to minimize environmental impact. Grape stems, rich in bioactive compounds and nutrients, have demonstrated potential health benefits. This study analysed four red grape stems from the Douro region to assess their nutritional value and potential health benefit. Tryptophan, selenium, and phenolic compounds, which regulate cognitive functions, protein and enzyme synthesis, and antioxidant processes, were analysed. Among the varieties, Touriga Nacional exhibited the highest levels of selenium, phenolics, and antioxidant capacity. Tinta Amarela and Touriga Nacional exhibited higher tryptophan levels. Moreover, proanthocyanidins, phenolic acids, flavonols, and anthocyanins were identified in all the varieties analysed. These findings highlight grape stems, particularly Touriga Nacional, as valuable sources of amino acids and bioactive compounds, offering potential in mood regulation, protein synthesis, and antioxidant defence. This research emphasizes their value to reduce waste, generating revenue, and promoting environmental sustainability.