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- Analysis of pharmaceutical adulterants in plant food supplements by UHPLC-MS/MSPublication . Paíga, 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 1000μg/l, depending on the compound, and good sensitivity with limits of quantification in the range of 0.02-9.80μg/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 (768μg/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.
- Assessment of 83 pharmaceuticals in WWTP influent and effluent samples by UHPLC-MS/MS: Hourly variationPublication . Paíga, Paula; Correia, Manuela; Fernandes, Maria João; 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 RQ > 1 in WWTP effluents.
- Bioactive Lipids of Seaweeds from the Portuguese North Coast: Health Benefits versus Potential ContaminationPublication . Soares, Cristina; Sousa, Sara; Machado, Susana; Vieira, Elsa; Carvalho, Ana P.; Ramalhosa, Maria João; Morais, Simone; Correia, Manuela; Oliva-Teles, MT; Domingues, Valentina; Delerue-Matos, CristinaThe total lipid content and lipidic profile of seaweeds harvested in the North Coast and purchased in Portugal were determined in this paper. The amount of total lipids in the different species of seaweeds varied between 0.7 ± 0.1% (Chondrus crispus) and 3.8 ± 0.6% (Ulva spp.). Regarding the fatty acid content, polyunsaturated fatty acids (PUFA) ranged between 0–35%, with Ulva spp. presenting the highest amount; monounsaturated fatty acids (MUFA) varied between 19 and 67%; and saturated fatty acids (SFA) were predominant in C. crispus (45–78%) and Gracilaria spp. (36–79%). Concerning the nutritional indices, the atherogenicity index (AI) was between 0.4–3.2, the thrombogenicity index (TI) ranged from 0.04 to 1.95, except for Gracilaria spp., which had a TI of 7.6, and the hypocholesterolemic/hypercholesterolemic ratio (HH) values ranged between 0.88–4.21, except for Gracilaria spp., which exhibited values between 0.22–9.26. The n6/n3 ratio was below 1 for most of the species evaluated, except for Ascophyllum nodosum, which presented a higher value, although below 2. Considering the PUFA/SFA ratio, seaweeds presented values between 0.11–1.02. The polycyclic aromatic hydrocarbons (PAHs) and aliphatic hydrocarbons (AHCs) contamination of seaweeds under study was also quantified, the values found being much lower than the maximum levels recommended for foodstuff.
- Removal of diclofenac and sulfamethoxazole from aqueous solutions and wastewaters using a three-dimensional electrochemical processPublication . Soares, Cristina; Correia-Sá, Luísa; Paíga, Paula; Barbosa, Carlos; Remor, Paula Verônica; Freitas, Olga; Moreira, Manuela M.; Nouws, Henri; Correia, Manuela; Ghanbari, Amir; Rodrigues, António J.; Oliveira, Carlos M.; Figueiredo, Sónia; Delerue-Matos, CristinaThe three-dimensional (3D) electrochemical treatment process was studied for the removal of two pharmaceuticals, diclofenac (anti-inflammatory) and sulfamethoxazole (antibiotic), in mono and bi-component systems. Adsorption and conventional two-dimensional electrochemical processes were initially studied and then combined to develop the 3D process. The influence of different operating parameters on the removal efficiency was studied: the distance between the cathode and the anode, the pharmaceutical and electrolyte (NaCl) concentrations, the pH, and the (carbon-based) adsorbent used as particulate electrode (biochar and commercial activated carbon, granulometry, and amount). The energy consumption and the electric energy per order were evaluated. The results demonstrate the efficiency of the 3D process for the removal of diclofenac and sulfamethoxazole from aqueous solutions, both for mono- and bi-component systems, achieving their complete removal respectively in 10 and 30 min, using a Mixed Metal Oxide anode (titanium-coated with RuO2-IrO2-TiO2), a stainless steel cathode, a biochar particulate electrode (1–2 mm), an initial pharmaceutical concentration of 10 mg/L, an inter-electrode distance of 7.5 cm, a pH value of 7 and a current density of 7 mA/cm2. The optimised 3D process was also successfully applied to a wastewater treatment plant effluent, but lower removal efficiencies were observed (after 30 min) for bi-component fortified samples; 49% for DCF and 86% for SMX, with energy consumptions of 1224 and 613 Wh/g and an electric energy per order of 19.1 and 8.77 kWh/m3 respectively. On the other hand, the pharmaceuticals were completely removed from the effluent when real concentrations (i.e. without their addition) were used
- Development of New Canned Chub Mackerel Products Incorporating Edible Seaweeds—Influence on the Minerals and Trace Elements CompositionPublication . Vieira, Elsa F.; Soares, Cristina; Machado, Susana; Oliva-Teles, MT; Correia, Manuela; Ramalhosa, Maria João; Carvalho, A.; Domingues, Valentina; Antunes, Filipa; Morais, Simone; Delerue-Matos, CristinaThis study aimed to develop new canned chub mackerel products incorporating edible seaweeds (Ascophyllum nodosum, Fucus spiralis, Saccorhiza polyschides, Chondrus crispus, Porphyra sp. and Ulva sp.) harvested in the Portuguese North-Central coast, with simultaneous sensory improvement and minerals enrichment. Two processes were compared, namely the addition of seaweeds in i) the canning step and ii) in the brining step (as the replacement for salt). The concentrations of four macrominerals (Na, K, Ca and Mg), chloride, and twelve trace elements (Co, Cu, Fe, I, Li, Mn, Mo, Rb, Se, Sr, V and Zn) were determined by high-resolution continuum source flame atomic absorption spectrometry (HR-CS-FAAS) and inductively coupled plasma mass spectrometry (ICP-MS), respectively. Results showed that canned chub mackerel incorporating C. crispus and F. spiralis was found to be the preferred sensory option, also exhibiting contents enriched with Cl, Co, Cu, Fe, I, Li, Mg, Mn, Mo, Na, Rb, Se, and Sr. This effect was more pronounced when both seaweed species were added to replace the salt added in the brining step.
- Investigating the Antioxidant Capacity of Fruits and Fruit Byproducts through an Introductory Food Chemistry Experiment for High SchoolPublication . Soares, Cristina; Correia, Manuela; Delerue-Matos, Cristina; Barroso, M. FátimaThis paper reports a laboratorial internship included in the Portuguese Science and Technology promotion program “Internships for Young People in Laboratories (Ciência Viva no Laboratório)”, which provided high school students an opportunity to approach the reality of scientific and technological research in a higher education institution. During this internship, students acquired knowledge related to the assessment of the total antioxidant capacity (TAC) of fruits and their byproducts while learning techniques, such as molecular spectrophotometry, as an analytical methodology to measure TAC using the ferric reducing antioxidant power (FRAP) and the total phenolic content (TPC) assays. First, the students were introduced to solid–liquid extraction as a conventional technique to extract antioxidants from the selected matrices. In order to optimize the extraction yield, different solvents, temperatures, and extraction times were used. Then, the students developed skills on TPC and FRAP assays by performing calibration curves using standard antioxidants, namely, gallic acid and ascorbic acid, prior to the measurement of the TAC of fruits (apple and orange) and respective byproducts. Final analysis included TAC values for comparison between fruits and their byproducts and also the influence of the extraction conditions on the TAC levels. At the end, the students presented their findings in a scientific poster and in a postlaboratory quiz. This laboratorial internship has been carried out since 2012 and was designed to be performed during a week, 7 h per day, in groups of two young students antioxidant power (FRAP) and the total phenolic content (TPC) assays. First, the students were introduced to solid−liquid extraction as a conventional technique to extract antioxidants from the selected matrices. In order to optimize the extraction yield, different solvents, temperatures, and extraction times were used. Then, the students developed skills on TPC and FRAP assays by performing calibration curves using standard antioxidants, namely, gallic acid and ascorbic acid, prior to the measurement of the TAC of fruits (apple and orange) and respective byproducts. Final analysis included TAC values for comparison between fruits and their byproducts and also the influence of the extraction conditions on the TAC levels. At the end, the students presented their findings in a scientific poster and in a postlaboratory quiz. This laboratorial internship has been carried out since 2012 and was designed to be performed during a week, 7 h per day, in groups of two young students.
- Anthelmintic, Antibacterial and Cytotoxicity Activity of Imidazole Alkaloids fromPilocarpus microphyllusLeavesPublication . Rocha, Jefferson A.; Andrade, Ivanilza M.; Véras, Leiz M.C.; Quelemes, Patrick V.; Lima, David F.; Soares, Maria J.S.; Pinto, Pedro L.S.; Mayo, Simon J.; Ivanova, Galya; Rangel, Maria; Correia, Manuela; Mafud, Ana Carolina; Mascarenhas, Yvonne P.; Delerue-Matos, Cristina; Moraes, Josué de; Eaton, Peter; Leite, José R.S.A.Pilocarpus microphyllus Stapf ex Wardlew (Rutaceae), popularly known as jaborandi, is a plant native to the northern and northeastern macroregions of Brazil. Several alkaloids from this species have been isolated. There are few reports of antibacterial and anthelmintic activities for these compounds. In this work, we report the antibacterial and anthelmintic activity of five alkaloids found in P. microphyllus leaves, namely, pilosine, epiisopilosine, isopilosine, epiisopiloturine and macaubine. Of these, only anthelmintic activity of one of the compounds has been previously reported. Nuclear magnetic resonance, HPLC and mass spectrometry were combined and used to identify and confirm the structure of the five compounds. As regards the anthelmintic activity, the alkaloids were studied using in vitro assays to evaluate survival time and damaged teguments for Schistosoma mansoni adult worms. We found epiisopilosine to have anthelmintic activity at very low concentrations (3.125 μg mL-1 ); at this concentration, it prevented mating, oviposition, reducing motor activity and altered the tegument of these worms. In contrast, none of the alkaloids showed antibacterial activity. Additionally, alkaloids displayed no cytotoxic effect on vero cells. The potent anthelmintic activity of epiisopilosine indicates the potential of this natural compound as an antiparasitic agent. Copyright © 2017 John Wiley & Sons, Ltd.
- Seaweeds from the Portuguese coast as a source of proteinaceous material: Total and free amino acid composition profilePublication . Vieira, Elsa Ferreira; Soares, Cristina; Machado, Susana; Correia, Manuela; Ramalhosa, Maria João; Oliva-Teles, MT; Carvalho, Ana; Domingues, Valentina; Antunes, Filipa; Oliveira, Teresa Azevedo Cardoso; Morais, Simone; Delerue-Matos, CristinaThe total protein content and the (total and free) amino acid composition of nine edible species of red, brown and green seaweeds collected in the Portuguese North-Central coast were quantified to assess their potential contribution to the recommended dietary intake. Whenever possible, the protein and amino acid composition was compared with that of commercial European seaweeds. The protein content was the highest (P < 0.05) in red species (19.1-28.2 g/100 g dw), followed by the green seaweed Ulva spp. (20.5-23.3 g/100 g dw), with the lowest content found in brown seaweeds (6.90-19.5 g/100 g dw). Brown seaweeds presented the lowest mean contents of essential amino acids (EAAs) (41.0% protein) but significantly (P < 0.05) higher concentrations of non-essential amino acids (36.1% protein) and free amino acids (6.47-24.0% protein). Tryptophan, methionine and leucine were the limiting EAAs in all species. In contrast, lysine was found in high concentrations, especially in red (2.71-3.85% protein) and green (2.84-4.24% protein) seaweeds.