A5006622583- Analytical chemistry methods development
- Mass Spectrometry Techniques and Applications
- Analytical Chemistry and Chromatography
- Phytochemicals and Antioxidant Activities
- Parkinson's Disease Mechanisms and Treatments
- Cholinesterase and Neurodegenerative Diseases
- Arsenic contamination and mitigation
- Alzheimer's disease research and treatments
- Pharmaceutical and Antibiotic Environmental Impacts
- Phytochemistry and Biological Activities
- Plant biochemistry and biosynthesis
- Electrochemical sensors and biosensors
- Free Radicals and Antioxidants
- Metabolomics and Mass Spectrometry Studies
- Environmental Toxicology and Ecotoxicology
- Natural product bioactivities and synthesis
- Computational Drug Discovery Methods
- Marine Biology and Environmental Chemistry
- Advanced Photocatalysis Techniques
- Advanced Glycation End Products research
- Protein Structure and Dynamics
- Biochemical Analysis and Sensing Techniques
- Electrochemical Analysis and Applications
- Alcohol Consumption and Health Effects
- Carbohydrate Chemistry and Synthesis
University of Lisbon
2013-2023
National Institute of Engineering, Technology and Innovation
2001
Universidade do Porto
2001
Instituto de Engenharia de Sistemas e Computadores Investigação e Desenvolvimento
1999
Universidade Lusófona
1993
AbstractThe metal chelating properties of flavonoids suggest that they may play a role in metal-overload diseases and all oxidative stress conditions involving transition ion. A detailed study has been made the ability to chelate iron (including Fe 3+ ) copper ions its dependence structure pH. The acid medium be important some pathological conditions. In addition, reduce their activity-structure relationships were also investigated. To fulfil these objectives, flavones (apigenin, luteolin,...
This study aims to determine the function of Plectranthus barbatus (Lamiaceae) herbal tea as inhibitor brain acetylcholinesterase (AChE) activity. To accomplish this objective well its main component, rosmarinic acid were administered laboratory animals (rats) and effect on AChE activity was evaluated. The metabolites in plasma also undertaken. water extract intragastrically intraperitoneally. When plant administered, vestigial amounts from P. compounds present rat plasma, but none found...
Abstract Flavonoids are important phytochemicals which have been intensively studied in the last decades view of their antioxidant activity, is particular importance case flavones and flavonols, that differ a single 3‐OH group. Mass spectrometry has used to elucidate structures many types flavonoids metabolites. The work we present here focused on electrospray ionization tandem mass (ESI‐MS/MS) analysis flavone flavonols aglycones. Their fragmentation mechanisms positive ion mode described...
Flavonoids are known to possess a broad set of pharmacological effects, some which have been attributed their antioxidant properties and, more recently, cell signalling modulation. Nevertheless, flavonoids extensively metabolized and metabolites the potential bioactive forms in vivo. Therefore, first crucial step understand mechanisms underlying health benefits is knowledge biological activities.To approximate human dietary pattern intake flavonoids, regular rat chow was supplemented with...
Cynara cardunculus, Fraxinus angustifolia and Pterospartum tridentatum are plants commercialized in Portugal for digestion-related ailments, among others. The aim of this study was to identify the chemical composition infusions determine inhibition acetylcholinesterase, antioxidant activity, evaluate if activities remained after vitro gastrointestinal digestion. These can be related with traditional uses these plants. toxicity also tested Caco-2 cells, a model intestinal cells. plant...
The objective of this study was to identify transformation products (TPs) citalopram (CIT), an antidepressant drug, in laboratory experiments. Moreover, toxicity predictions and analyzes wastewater samples were performed. For the formation TPs, raw water used for processes hydrolysis; photodegradation under ultraviolet (UV) irradiation chlorination. toxicities predicted by computational assessment. TPs identified liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF/MS)...
Abstract The use of inorganic species as assisting materials in matrix‐assisted laser desorption/ionization (MALDI) analysis is an alternative approach to avoid interfering matrix ions the low‐mass region mass spectra. Reports application matrices MALDI small molecules are, however, scarce. Nevertheless, titanium dioxide (TiO 2 ) powder has been reported be a promising medium. In this study we further explore TiO for low molecular weight compounds. We present results showing that nanosized...
Acetylcholinesterase (AChE) inhibition is one of the most currently available therapies for management Alzheimer's disease (AD) symptoms. In this context, NMR spectroscopy binding studies were accomplished to explain AChE activity by Salvia sclareoides extracts. HPLC-MS analyses acetone, butanol and water extracts eluted with methanol acidified showed that rosmarinic acid present in all studied samples a major constituent Moreover, luteolin 4'-O-glucoside, 3',7-di-O-glucoside...
Controlled silylation of friedelin (1) from cork smoker wash solids, a byproduct generated during processing corkboard by steam baking, gave 3-trimethylsiloxyfriedel-2-ene (3) in high yields. Oxidation 3 with OsO4/NMMO produced 2α-hydroxyfriedelan-3-one (cerin) (5), which the new 2,3-secofriedelan-2-al-3-oic acid (6) was obtained quantitatively periodic oxidation. DDQ afforded friedel-1-en-3-one (8). Reductive ozonolysis 2α,3β-dihydroxyfriedelane, pachysandiol A (7). Compound 6 proved to be...
Abstract Five isoflavones, daidzein, genistein, formononetin, prunetin and biochanin A, known for their biological properties, are investigated by electrospray ionization mass spectrometry in the positive ion mode. The most probable protonation sites determined taking into account semi‐empirical calculations using PM6 Hamiltonian. Fragmentation mechanisms proposed based on accurate measurements, MS 3 experiments supported calculations. Some of fragmentation pathways were found to be...
Hypobromous acid (HOBr) produced by both eosinophil peroxidase (EPO) and myeloperoxidase (MPO) is a stronger oxidant than HOCl, also essential for optimal efficient microbial killing. Considering the potential cytotoxic effect of HOBr, if it formed outside phagosome, should be useful to scavenge in order protect nearby tissues. In this study ability selected flavonoids against HOBr mediated oxidation reactions was performed through competitive reaction, resulting products identified high...