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- Evaluation of the Biological Potential of Himanthalia elongata (L.) S.F.Gray and Eisenia bicyclis (Kjellman) Setchell Subcritical Water ExtractsPublication . Gomes, InĆŖs; Rodrigues, Helena; Rodrigues, Carla; Oliveira, Marta Marques; PaĆga, Paula; Paiva, Alexandre; SimƵes, Pedro; Fernandes, VirgĆnia Cruz; Vieira, MĆ³nica; Delerue-Matos, Cristina; Soares, Cristina; Grosso, ClaraNeuroprotection is a need that remains unmet in treating chronic neurodegenerative disorders, despite decades of extensive research. To find new neuroprotective compounds, extracts of Himanthalia elongata (L.) S.F.Gray and of Eisenia bicyclis (Kjellman) Setchell were obtained through subcritical water extraction applying a four-step temperature gradient. The fractions obtained were screened against brain enzymes involved in neurodegenerative etiology, namely in Alzheimerās and Parkinsonās diseases, and against reactive oxygen and nitrogen species, all contributing factors to the progression of neurodegeneration. Results showed no significant enzyme inhibition but strong radical scavenging activities, particularly in the fourth fraction, extracted at the highest temperature (250 Ā°C), highlighting their ability to retard oxidative and nitrosative stresses. At higher temperatures, fractions were composed of phenolic compounds and Maillard reaction products, a combination that contributed to their antioxidant activity and, consequently, their neuroprotective properties. All fractions were evaluated for the presence of iodine, 14 organochlorine and 7 organophosphorus pesticides, and pharmaceuticals used in Alzheimerās and Parkinsonās diseases (14), psychiatric drugs (8), and metabolites (8). The fractions studied did not present any of the screened contaminants, and only fraction 1 of E. bicyclis should be used with caution due to iodine content.
- Analysis of pharmaceutical adulterants in plant food supplements by UHPLC-MS/MSPublication . PaĆga, Paula; Rodrigues, Manuela J.E.; Correia, Manuela; Amaral, Joana S.; Oliveira, M. Beatriz P.P.; Delerue-Matos, CristinaA method based on the Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) extraction and ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS) was successfully developed and validated for the analysis of 26 pharmaceutical compounds belonging to different therapeutic classes (anorexics, stimulants, anxiolytics, antidepressants and laxatives), which are all prone to be illegally added into weight-loss plant food supplements (PFS) for their pharmacological activity. Internal standard calibration with six isotopically labelled compounds rendered good linearity in the range of 5 to 1000Ī¼g/l, depending on the compound, and good sensitivity with limits of quantification in the range of 0.02-9.80Ī¼g/l. Recoveries were assessed for all the 16 samples analysed and were found between 70% and 120% for over 90% of the analytes. The average recovery value was 90.8%, for the different studied matrices (liquids, liquid ampoules, tablets and capsules), with RSD values lower than 10% for all forms. The changes introduced to the QuEChERS procedure maintained the good performance characteristics of the extraction method while preserving the chromatographic system for the introduction of unwanted matrix compounds. Synephrine was the only compound detected and quantified in one sample, but at a very low concentration (768Ī¼g/l) and its presence may be due to the plant extracts used in the formulation, as synephrine is known to be a natural constituent of Citrus aurantium amara. Despite none of the 16 evaluated samples were found to be adulterated by the illegal addition of the drugs included in this work, the developed methodology can be very useful for monitoring the adulteration of weight-loss PFS.
- Determination of pharmaceuticals in groundwater collected in five cemeteries' areas (Portugal)Publication . PaĆga, Paula; Delerue-Matos, CristinaThere are growing public attention and concern about the possibility of ecosystemand human health effects from pharmaceuticals in environment. Several types of environmental samples were target of studies by the scientific community, namely drinkingwater, groundwater, surfacewater (river, ocean), treated water (influent and effluent), soils, and sediments near to Wastewater Treatment Plants or near to others potential sources of contaminations. Normally, studies in the cemeteries areas are for historical and architectural research and questions of the potential risk for adverse impact of cemeteries in environment have never received enough attention. However, this risk may exist when cemeteries are placed in areas that are vulnerable to contamination. The objective of the present work was the determination of pharmaceuticals (nonsteroidal anti-inflammatory/ analgesics, antibiotics and psychiatric drugs) in groundwater samples collected inside of the cemeteries areas. Acetaminophen, salicylic acid, ibuprofen, ketoprofen, nimesulide, carbamazepine, fluoxetine, and sertraline were the pharmaceuticals achieved in the analysed samples. None of the studied antibiotics were detected. The highest concentration was obtained for salicylic acid (in the range of 33.7 to 71.0 ng/L) and carbamazepine (between 20.0 and 22.3 ng/L), respectively. By the cluster analysis similarity between carbamazepine and fluoxetine was achieved.
- Evaluation of the adsorption potential of biochars prepared from forest and agri-food wastes for the removal of fluoxetinePublication . Fernandes, Maria JoĆ£o; Moreira, Manuela M.; PaĆga, Paula; Dias, Diogo; Bernardo, Maria; Carvalho, Maria Manuela; Lapa, Nuno; Fonseca, Isabel; Morais, Simone; Figueiredo, SĆ³nia; Delerue-Matos, CristinaTwelve biochars from forest and agri-food wastes (pruning of Quercus ilex, Eucalyptus grandis, Pinus pinaster, Quercus suber, Malus pumila, Prunus spinosa, Cydonia oblonga, Eriobotrya japonica, Juglans regia, Actinidia deliciosa, Citrus sinensis and Vitis vinifera) were investigated as potential low-cost and renewable adsorbents for removal of a commonly used pharmaceutical, fluoxetine. Preliminary adsorption experiments allowed to select the most promising adsorbents, Quercus ilex, Cydonia oblonga, Eucalyptus, Juglans regia and Vitis vinifera pruning material. They were characterized by proximate, elemental and mineral analysis, thermogravimetric analysis, Fourier transform infrared spectroscopy, determination of specific surface area and pH at the point of zero charge. Batch and equilibrium studies were performed, and the influence of pH was evaluated. The equilibrium was reached in less than 15āÆmin in all systems. The maximum adsorption capacity obtained was 6.41āÆmg/g for the Eucalyptus biochar, which also demonstrated a good behavior in continuous mode (packed column).
- Optimization of the Ion Source-Mass Spectrometry Parameters in Non-Steroidal Anti-Inflammatory and Analgesic Pharmaceuticals Analysis by a Design of Experiments ApproachPublication . PaĆga, Paula; Silva, LuĆs M. S.; Delerue-Matos, CristinaThe flow rates of drying and nebulizing gas, heat block and desolvation line temperatures and interface voltage are potential electrospray ionization parameters as they may enhance sensitivity of the mass spectrometer. The conditions that give higher sensitivity of 13 pharmaceuticals were explored. First, Plackett-Burman design was implemented to screen significant factors, and it was concluded that interface voltage and nebulizing gas flow were the only factors that influence the intensity signal for all pharmaceuticals. This fractionated factorial design was projected to set a full 2(2) factorial design with center points. The lack-of-fit test proved to be significant. Then, a central composite face-centered design was conducted. Finally, a stepwise multiple linear regression and subsequently an optimization problem solving were carried out. Two main drug clusters were found concerning the signal intensities of all runs of the augmented factorial design. p-Aminophenol, salicylic acid, and nimesulide constitute one cluster as a result of showing much higher sensitivity than the remaining drugs. The other cluster is more homogeneous with some sub-clusters comprising one pharmaceutical and its respective metabolite. It was observed that instrumental signal increased when both significant factors increased with maximum signal occurring when both codified factors are set at level +1. It was also found that, for most of the pharmaceuticals, interface voltage influences the intensity of the instrument more than the nebulizing gas flowrate. The only exceptions refer to nimesulide where the relative importance of the factors is reversed and still salicylic acid where both factors equally influence the instrumental signal. Graphical Abstract į .
- Assessment of 83 pharmaceuticals in WWTP influent and effluent samples by UHPLC-MS/MS: Hourly variationPublication . PaĆga, Paula; Correia, Manuela; Fernandes, Maria JoĆ£o; Silva, Ana Margarida; Martins de Carvalho, Maria Manuela; Vieira, Joana; Jorge, Sandra; Silva, Jaime Gabriel; Freire, Cristina; Delerue-Matos, CristinaThe removal efficiency of pharmaceuticals in wastewater treatment plants (WWTPs) is variable and some of these compounds pass these plants almost intact and others presenting a removal efficiency close to 100%. Their incomplete removal results in a continuous discharge of pharmaceuticals into the environment. To assess the profile of contamination of influents and effluents over a day, a set of 83 pharmaceuticals were evaluated hourly in a WWTP in Leiria, Portugal. The composite samples of the influent and effluent were also collected. Concentrations varied from 1 in WWTP influents, and carbamazepine, fluoxetine, sertraline the pharmaceuticals with an RQāÆ>āÆ1 in WWTP effluents.
- Pilot monitoring study of ibuprofen in surface waters of north of PortugalPublication . PaĆga, Paula; Santos, LĆŗcia; Amorim, CĆ©lia G.; AraĆŗjo, Alberto N.; Montenegro, M. ConceiĆ§Ć£o B. S. M.; Pena, Angelina; Delerue-Matos, CristinaIbuprofen is amongst the most worldwide consumed pharmaceuticals. The present work presents the first data in the occurrence of ibuprofen in Portuguese surface waters, focusing in the north area of the country, which is one of the most densely populated areas of Portugal. Analysis of ibuprofen is based on pre-concentration of the analyte with solid phase extraction and subsequent determination with liquid chromatography coupled to fluorescence detection. A total of 42 water samples, including surface waters, landfill leachates,Wastewater Treatment Plant (WWTP), and hospital effluents, were analyzed in order to evaluate the occurrence of ibuprofen in the north of Portugal. In general, the highest concentrations were found in the river mouths and in the estuarine zone. The maximum concentrations found were 48,720 ngLā1 in the landfill leachate, 3,868 ngLā1 in hospital effluent, 616 ngLā1 in WWTP effluent, and 723 ngLā1 in surface waters (Lima river). Environmental risk assessment was evaluated and at the measured concentrations only landfill leachates reveal potential ecotoxicological risk for aquatic organisms. Owing to a high consumption rate of ibuprofen among Portuguese population, as prescribed and nonprescribed medicine, the importance of hospitals, WWTPs, and landfills as sources of entrance of pharmaceuticals in the environment was pointed out. Landfill leachates showed the highest contribution for ibuprofen mass loading into surface waters. On the basis of our findings, more studies are needed as an attempt to assess more vulnerable areas.
- Study of the voltammetric behaviour of metam and its application to an amperometric flow systemPublication . Barroso, M. FĆ”tima; PaĆga, Paula; Vaz, M. Carmo V. F.; Delerue-Matos, CristinaThe electrochemical behaviour of the pesticide metam (MT) at a glassy carbon working electrode (GCE) and at a hanging mercury drop electrode (HMDE) was investigated. Different voltammetric techniques, including cyclic voltammetry (CV) and square wave voltammetry (SWV), were used. An anodic peak (independent of pH) at +1.46 V vs AgCl/Ag was observed in MTaqueous solution using the GCE. SWV calibration curves were plotted under optimized conditions (pH 2.5 and frequency 50 Hz), which showed a linear response for 17ā29 mg Lā1. Electrochemical reduction was also explored, using the HMDE. A well defined cathodic peak was recorded at ā0.72 V vs AgCl/ Ag, dependent on pH. After optimizing the operating conditions (pH 10.1, frequency 150 Hz, potential deposition ā0.20 V for 10 s), calibration curves was measured in the concentration range 2.5Ć10ā1 to 1.0 mg Lā1 using SWV. The electrochemical behaviour of this compound facilitated the development of a flow injection analysis (FIA) system with amperometric detection for the quantification of MT in commercial formulations and spiked water samples. An assessment of the optimal FIA conditions indicated that the best analytical results were obtained at a potential of +1.30 V, an injection volume of 207 Ī¼L and an overall flow rate of 2.4 ml minā1. Real samples were analysed via calibration curves over the concentration range 1.3Ć10ā2 to 1.3 mg Lā1. Recoveries from the real samples (spiked waters and commercial formulations) were between 97.4 and 105.5%. The precision of the proposed method was evaluated by assessing the relative standard deviation (RSD %) of ten consecutive determinations of one sample (1.0 mg Lā1), and the value obtained was 1.5%.
- A multibiomarker approach highlights effects induced by the human pharmaceutical gemfibrozil to gilthead seabream Sparus aurataPublication . Barreto, A.; Luis, L.G.; PaĆga, Paula; Santos, L.H.M.L.M.; Delerue-Matos, Cristina; Soares, A.M.V.M.; Hylland, K.; Loureiro, S.; Oliveira, M.Lipid regulators are among the most prescribed human pharmaceuticals worldwide. Gemfibrozil, which belongs to this class of pharmaceuticals, is one of the most frequently encountered in the aquatic environment. However, there is limited information concerning the mechanisms involved in gemfibrozil effects to aquatic organisms, particularly to marine organisms. Based on this knowledge gap, the current study aimed to assess biochemical and behavioral effects following a sublethal exposure to gemfibrozil (1.5, 15, 150, 1500 and 15,000āÆĪ¼gāÆL-1) in the estuarine/marine fish Sparus aurata. After the exposure to 1.5āÆĪ¼gāÆL-1 of gemfibrozil, fish had reduced ability to swim against a water flow and increased lipid peroxidation in the liver. At concentrations between 15-15,000āÆĪ¼gāÆL-1, the activities of some enzymes involved in antioxidant defense were induced, appearing to be sufficient to prevent oxidative damage. Depending on the organ, different responses to gemfibrozil were displayed, with enzymes like catalase being more stimulated in gills, whereas glutathione peroxidase was more activated in liver. Although there were no obvious concentration-response relationships, the integrated biomarker response version 2 (IBRv2) analysis revealed that the highest concentrations of gemfibrozil (between 150-15,000āÆĪ¼gāÆL-1) caused more alterations. All the tested concentrations of gemfibrozil induced effects in S. aurata, in terms of behavior and/or oxidative stress responses. Oxidative damage was found at a concentration that is considered environmentally relevant, suggesting a potential of this pharmaceutical to impact fish populations.
- Extraction of ochratoxin A in bread samples by the QuEChERS methodologyPublication . PaĆga, Paula; Morais, Simone; Oliva-Teles, Maria Teresa; Correia, Manuela; Delerue-Matos, Cristina; Duarte, S. C.; Pena, Angelina; Lino, C. M.A QuEChERS method for the extraction of ochratoxin A (OTA) from bread samples was evaluated. A factorial design (23) was used to find the optimal QuEChERS parameters (extraction time, extraction solvent volume and sample mass). Extracts were analysed by LC with fluorescence detection. The optimal extraction conditions were: 5 g of sample, 15 mL of acetonitrile and 3 min of agitation. The extraction procedure was validated by systematic recovery experiments at three levels. The recoveries obtained ranged from 94.8% (at 1.0 Ī¼g kg -1) to 96.6% (at 3.0 Ī¼g kg -1). The limit of quantification of the method was 0.05 Ī¼g kg -1. The optimised procedure was applied to 20 samples of different bread types (āāCarcaƧaāā, āāBroa de Milhoāā, and āāBroa de Avintesāā) highly consumed in Portugal. None of the samples exceeded the established European legal limit of 3 Ī¼g kg -1.