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Projeto de investigação
Life Sciences for a Healthy and Sustainable Future
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Adding value to chicory roots: Evaluation of the anti-inflammatory potential of terpenes for application in Inflammatory Bowel Disease
Publication . Matos, Melanie S.; Matias, Ana; Santos, Cláudia; Serra, Ana Teresa
"Inflammatoryboweldisease(IBD)isachronicgastrointestinalconditionaffecting
nearly 5millionindividualsglobally,posingasubstantialpublichealthchallenge.IBD
is amultifactorialdisorder,involvinganintricateinterplayamongtheimmunesystem,
environmentalfactors,geneticsusceptibility,andalterationsingutmicrobiota.Upto
date,thereisnocureforIBD,andcurrenttherapeuticstrategieshaveinherentlimi-
tations.Apartfromtheirhighcosts,thesesymptomatictreatmentsexhibitsideeffects
and oftenexperiencediminishedefficacyovertime,leadingtoarecurrentpatternofre-
lapseandremission.GiventhemultifacetednatureofIBDanditsindividualvariability,
thereisanurgentdemandforthediscoveryofinnovativeandeffectivepharmacological
leads, toaddresstheshortcomingsassociatedwithexistingtherapies.(...)"
Studies on the Interaction between Model Proteins and Fluorinated Ionic Liquids
Publication . Alves, Márcia M. S.; Melo, Manuel N.; Mertens, Haydyn D. T.; Pereiro, Ana B.; Archer, Margarida; Instituto de Tecnologia Química e Biológica António Xavier (ITQB); DQ - Departamento de Química; MDPI AG
Proteins are inherently unstable, which limits their use as therapeutic agents. However, the use of biocompatible cosolvents or surfactants can help to circumvent this problem through the stabilization of intramolecular and solvent-mediated interactions. Ionic liquids (ILs) have been known to act as cosolvents or surface-active compounds. In the presence of proteins, ILs can have a beneficial effect on their refolding, shelf life, stability, and enzymatic activities. In the work described herein, we used small-angle X-ray scattering (SAXS) to monitor the aggregation of different concentrations of ILs with protein models, lysozyme (Lys) and bovine serum albumin (BSA), and fluorescence microscopy to assess micelle formation of fluorinated ILs (FILs) with Lys. Furthermore, coarse-grained molecular dynamics (CG-MD) simulations provided a better understanding of Lys–FIL interactions. The results showed that the proteins maintain their globular structures in the presence of FILs, with signs of partial unfolding for Lys and compaction for BSA with increased flexibility at higher FIL concentrations. Lys was encapsulated by FIL, thus reinforcing the potential of ILs to be used in the formulation of protein-based pharmaceuticals.
Spectroscopic and Structural Characterization of Reduced Desulfovibrio vulgaris Hildenborough W-FdhAB Reveals Stable Metal Coordination during Catalysis
Publication . Oliveira, Ana Rita; Mota, Cristiano; Klymanska, Kateryna; Biaso, Frederic; Romão, Maria Joao; Guigliarelli, Bruno; Pereira, Inês Cardoso; Instituto de Tecnologia Química e Biológica António Xavier (ITQB); UCIBIO - Applied Molecular Biosciences Unit; DQ - Departamento de Química; ACS - American Chemical Society
Metal-dependent formate dehydrogenases are important enzymes due to their activity of CO2reduction to formate. The tungsten-containing FdhAB formate dehydrogenase from Desulfovibrio vulgaris Hildenborough is a good example displaying high activity, simple composition, and a notable structural and catalytic robustness. Here, we report the first spectroscopic redox characterization of FdhAB metal centers by EPR. Titration with dithionite or formate leads to reduction of three [4Fe-4S]1+clusters, and full reduction requires Ti(III)-citrate. The redox potentials of the four [4Fe-4S]1+centers range between -250 and -530 mV. Two distinct WVsignals were detected, WDVand WFV, which differ in only the g2-value. This difference can be explained by small variations in the twist angle of the two pyranopterins, as determined through DFT calculations of model compounds. The redox potential of WVI/Vwas determined to be -370 mV when reduced by dithionite and -340 mV when reduced by formate. The crystal structure of dithionite-reduced FdhAB was determined at high resolution (1.5 Å), revealing the same structural alterations as reported for the formate-reduced structure. These results corroborate a stable six-ligand W coordination in the catalytic intermediate WVstate of FdhAB.
Arabinoxylan from Corn Fiber Obtained through Alkaline Extraction and Membrane Purification
Publication . Weng, Verónica; Cardeira, Martim; Bento-Silva, Andreia; Serra, Ana Teresa; Brazinha, Carla; Bronze, Maria Rosário; DQ - Departamento de Química; LAQV@REQUIMTE; Instituto de Tecnologia Química e Biológica António Xavier (ITQB); MDPI - Multidisciplinary Digital Publishing Institute
Arabinoxylan has prebiotic properties, as it is able to resist digestion in the small intestine and undergoes fermentation in the large intestine. In this work, arabinoxylan was extracted from corn fiber using an alkaline solution and further purified with membrane processing. It was found that the extracts were mainly composed of xylose (50–52%), arabinose (37–39%), galactose (9%) and glucose (1–4%), with an A/X ratio of 0.72–0.77. All the extracts were composed of phenolic compounds, including ferulic acid derivatives such as dimers, trimers and tetramers. The purified extract had a lower concentration of ferulic and p-coumaric acid (0.004 and 0.02 mg/mgdry_weight, respectively) when compared to raw extract (19.30 and 2.74 mg/mgdry_weight, respectively). The same effect was observed for the antioxidant activity, with purified extracts having a lower value (0.17 ± 0.02 µmol TEAC/mg) when compared to the raw extract (2.20 ± 0.35 µmol TEAC/mg). The purified extract showed a greater antiproliferative effect against the HT29 cell line with EC50 = 0.12 ± 0.02 mg/mL when compared to the raw extract (EC50 = 5.60 ± 1.6 mg/mL). Both raw and purified extracts did not show any cytotoxicity to the Caco-2 cell line in the maximum concentration tested (10 mg/mL).
Sustainable production of nanoemulsions by membrane-assisted nanoemulsification using novel aroma-based hydrophobic deep eutectic solvents for enhanced antifungal activities
Publication . Mondal, S.; Syed, U. T.; Pinto, E.; Leonardo, I. C.; Romero, P.; Gaspar, F. B.; Crespo, M. T. Barreto; Sebastian, V.; Crespo, J. G.; Brazinha, C.; DQ - Departamento de Química; LAQV@REQUIMTE; Instituto de Tecnologia Química e Biológica António Xavier (ITQB); Elsevier
Hydrophobic deep eutectic solvents (DESs), a recent class of green solvents, offer 100% atom economy, low cost, potential biodegradability, negligible toxicity and promising bioactivities. In this work, novel aroma-based therapeutic hydrophobic DESs were prepared and dispersed in aqueous media as nanoemulsions to potentiate biomedical applications, where polar media is encountered. A reusable microengineered stainless-steel isoporous membrane was fabricated by laser drilling technique. Three hydrophobic DESs, namely DES A (menthol and vanillin), DES B (menthol and raspberry ketone), and DES C (thymol and raspberry ketone) were prepared and emulsified in aqueous media by sustainable membrane emulsification technique. The optimised nanoemulsion (DES C-in-water) exhibited a monomodal size distribution with Zavg (size average) of 147 nm and polydispersity index of 0.22. From the application perspective, the formulated DES-in-water nanoemulsions and their constituents were evaluated for their antibacterial properties against Escherichia coli and Staphylococcus aureus. Additionally, antifungal properties of the DES-based emulsions were reported for the first time by testing them against four fungal strains, Aspergillus fumigatus, Candida albicans, Candida krusei, and Trichophyton mentagrophytes. The nanoemulsions were found to be exhibit antimicrobial effect and lesser quantities of individual compounds were needed in nanoemulsified state to show similar effects. Different 1D and 2D NMR techniques were successfully used to investigate the structural orientation and the inter and intramolecular interactions in the DES and emulsion systems, which revealed a probable cause for higher antimicrobial activity of DES C-based emulsions compared to its peers. Lastly, a synergistic effect of the components in nanoemulsions led to enhanced antimicrobial activities.
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Entidade financiadora
Fundação para a Ciência e a Tecnologia
Programa de financiamento
6817 - DCRRNI ID
Número da atribuição
LA/P/0087/2020