Browsing by Author "Pereira, Catarina"
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- A comparative study of the in vitro enzyme inhibitory and antioxidant activities of Butea monosperma (Lam.) Taub. and Sesbania grandiflora (L.) Poiret from Pakistan: New sources of natural products for public health problemsPublication . Baessa, M.; Rodrigues, Maria João; Pereira, Catarina; Santos, T.; Neng, N. da Rosa; Nogueira, J. M. F.; Barreira, Luísa; Varela, J.; Ahmed, H.; Asif, S.; Boukhari, S. A.; Kayani, W. K.; Ahmad, Khawaja Shafique; Zengin, G.; Mollica, A.; Custódio, LuísaInfusions, decoctions and tinctures were prepared from flowers of Butea monosperma (Lam.) Taub. and Sesbania grandiflora (L.) Poiret and evaluated for in vitro inhibition of enzymes implicated on the onset of neurological diseases (acetylcholinesterase: AChE and butyrylcholinesterase: BuChE), diabetes (alpha-glucosidase and alpha-amylase), obesity (lipase) and skin hyperpigmentation (tyrosinase). Extracts were also appraised for radical scavenging activity (RSA) on 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radicals, and for metal chelating activity on copper and iron ions. Samples were evaluated for their total contents in different phenolics groups by spectrophotometric methods, for phenolic profile by high performance liquid chromatography e diode array detection (HPLC-DAD) and for mineral contents by microwave plasma-atomic emission spectrometry (MP-AE). Regarding B. monosperma, the tincture allowed for a moderate inhibition of AChE, the decoction was able to inhibit alpha-glucosidase and no activity was observed towards BuChE, alpha-amylase or lipase. All extracts had a low or moderate inhibition towards tyrosinase, and significant RSA and metal chelating potential. As for S. grandiflora, only the decoction inhibited AChE, none of the extracts was able to inhibit BuChE, all samples inhibited alpha-glucosidase and infusions and decoctions had similar inhibitory properties towards alpha-amylase. None of the extracts was active against lipase, but all were able to inhibit tyrosinase. Extracts had also significant RSA, moderate copper chelation and decoctions had the capacity to chelate iron. The most abundant macroelements in both species were potassium and calcium, while iron was the prevalent microelement, especially in B. monosperma. Both species had significant levels of phenolic compounds, and the main components in decoctions and infusions of B. monosperma were syringic and salicylic acids, while the major compound identified in tinctures was the flavonoid luteolin-7-O-glucoside. In S. grandiflora the most abundant were chlorogenic and neochlorogenic acids and catechin hydrate. Molecular docking studies on the most abundant molecules in S. grandiflora, (+)-catechin, chlorogenic acid and neochlorogenic acid, indicate that these compounds are able to dock to alpha-glucosidase in a similar manner than acarbose. Our results suggest that flowers of both species are a promising source of high value-added compounds with enzyme inhibitory and antioxidant properties. (c) 2018 SAAB. Published by Elsevier B.V. All rights reserved.
- Alumni’s perceptions about commitment towards their university: drivers and consequencesPublication . Pedro, Ilda; Mendes, Júlio da Costa; Pereira, Catarina; Sequeira, BernardeteThis paper intends to capture alumni's assessments and perceptions about decisive dimensions of their commitment towards their alma mater. Their academic experience and current situation are highlighted. Moreover, their perception about the role of Higher Education Institution (HEI) in this commitment-relationship is likewise valuable to get their involvement. The study took place at a Portuguese university. Three focus groups, with 21 participants, were conducted to get consistent information permitting further developments. Data were analysed through NVivo software.The study gives insights revealing dimensions such as the relationships with teachers, extracurricular activities and initiation as decisive in their academic experience. Recommending and sharing their experience, underline evidence of what they are willing to give back. Moreover, their consciousness of bearing a mission to contribute to HEI's development was expressed through strong positive feelings, such as the sense of belonging, and pride at being part of the university, defined in their statements. But they all demand an effective ability of the university to communicate with them. Overall conclusions offer a scenario of alumni's commitment, giving HEI's management valuable clues to improvement, but its responsibility in this commitment-relationship was also stressed. Moreover, results also provide contributions to literature enabling other HEIs to replicate the study or simply use the results for their own development. Since the study occurred in a relatively weak alumni culture context, revealing the importance in promoting debate as a means to engage alumni in HEI's efforts for success, it presents insights for further developments in similar higher education environments.
- Chemical composition and biological screening of the essential oils of Micromeria macrosiphon and M. arganietorum (Lamiaceae)Publication . El Yaagoubi, Mohamed; Mechqoq, Hicham; Ortiz, Sergio; Cavaleiro, Carlos; Lecsö‐Bornet, Marylin; Pereira, Catarina; Rodrigues, Maria Joao; Custódio, Luísa; El Mousadik, Abdelhamid; Picot, Laurent; Kritsanida, Marina; Msanda, Fouad; El Aouad, Noureddine; Grougnet, RaphaëlThe chemical composition and in vitro biological activities of the essential oil (EO) of Micromeria macrosiphon Coss. and M. arganietorum (J. Emb.) R. Morales, two Lamiaceae endemic to south Morocco, were investigated. GC/MS analysis resulted in the identification of 36 metabolites from the EO of M. macrosiphon, 45 from M. arganietorum. Borneol was the major metabolite in both oils and together with related derivatives such as camphor, accounted for 2/3 of the EO of M. macrosiphon, 1/3 of those of M. arganietorum. Pinene and terpinene derivatives were also present in high proportions. From a chemotaxonomic point of view, the composition of the examined samples may be related to those of other species endemic to Macaronesia. Both EOs showed significant toxicity towards liver HepG2 and melanoma B16 4A5 tumor cell lines at 100 mu g/mL; however, they were also cytotoxic towards S17 normal cell lines, with a selectivity index <1. No antibacterial activity was noticed against 52 strains at 100 mu g/mL.
- Chemical profile, antioxidant, antimicrobial, enzyme inhibitory, and cytotoxicity of seven Apiaceae species from Turkey: a comparative studyPublication . Zengin, Gokhan; Sinan, Kouadio Ibrahime; Ak, Gunes; Mahomoodally, Mohamad Fawzi; Paksoy, Mehmet Yavuz; Picot-Allain, Carene; Glamocilja, Jasmina; Sokovic, Marina; Jeko, Jozsef; Cziaky, Zoltan; Rodrigues, Maria Joao; Pereira, Catarina; Custódio, LuísaSeveral Apiaceae species, used as both food and in complementary and alternative medicine, represents a rich source of potential valuable phytopharmaceuticals which necessitates scientific contemplation. In the present study, the antioxidant, enzyme inhibitory, antimicrobial, and cytotoxic properties of methanol extracts of seven Apiaceae species, (Chaerophyllum macrospermum (Willd. ex Spreng.) Fisch. & C.A.Mey. ex Hohen, Ferula rigidula Fisch. ex DC., Ferula orientalis L., Prangos ferulacea Lindl., Prangos peucedanifolia Fenzl., Ferulago setifolia K. Koch, and Pimpinella anthriscoides Boiss.) were evaluated. Species belonging to the Prangos genus exhibited the highest total phenolic content, namely P. peucedanifolia and P. ferulacea, with values of 47.90 and 44.44 mg gallic acid equivalent/g extract, respectively. P. peucedanifolia also displayed the highest radical scavenging capacity (81.53 and 102.70 mg Trolox equivalent [TE]/g extract for 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS), respectively) and reducing power (165.87 and 100.09 mg TE/g extract for cupric reducing antioxidant capacity (CUPRAC) and ferric reducing antioxidant power (FRAP), respectively). C. macrospermum showed the most potent inhibition against Alzheimer's disease related enzymes, namely acetylcholinesterase (4.53 mg galantamine equivalent [GALAE]/g extract) and butyrylcholinesterase (3.22 mg GALAE/g extract). P. ferulacea (131.94 mg kojic acid (KAE) equivalent/g extract) and P. peucedanifolia (4.97 mmol acarbose equivalent (ACAE)/g extract) were potent inhibitors of tyrosinase and a-glucosidase, respectively. In general, studied species were able to reduce cellular viabilities. P. peucedanifolia possessed promising antibacterial potential against Bacillus cereus (Minimum inhibition concentration (MIC): 0.37 mg/mL), L. monocytogenes (MIC: 0.56 mg/mL), P. aeruginosa and Escherichia coli (MIC: 0.27 mg/mL), Salmonella typhimurium and Enterobacter cloacae (MIC: 0.75 mg/mL). F. rigidula showed the highest antifungal effect against Aspergillus ochraceus and Trichoderma viride (MIC: 0.10 mg/mL). The present findings could be the scientific starting point towards the pharmaceutical and/or commercial utilization of these Apiaceae species.
- Construction and validation of the proposal for safety and emergency material and equipment in mountain sportsPublication . Mata, Carlos Daniel Gomes; Pereira, Catarina; Carvalhinho, LuísIntroduction: This study aimed to build and validate a proposal for safety and emergency material and equipment adjusted to the practice of mountain sports in Portugal. The proposal was developed through documentary analysis, literature review, and expert consultation. Methods: The validation of the contents of the proposal was carried out using the Delphi technique, with the participation of 30 experts, male (N = 18) and female (N = 12), aged between 32 and 61 years (M = 42.50; SD = 7.29), with a mean of 16.63 ± 5.60 years of experience, divided into 4 groups: (i) pre-hospital trainers; (ii) pre-hospital nurses; (iii) pre-hospital physicians; (iv) higher education teachers in the field of mountain sports. The 1st version of the proposal was structured in 7 areas and included 29 items (material and/or equipment). The final version of the proposal was structured in 8 areas (general material, measuring equipment, burns, trauma, respiratory, medication, communications, and survival kit) and included 44 items (material and equipment). Results: The proposal showed Content Validity Index (CVI) values of 100%. Concerning the reliability and validity of the proposal, intraclass correlation coefficient values of 0.986 (excellent) were found for technical importance and 0.983 (excellent) for contextual fit. All values show a high level of inter-expert agreement. Conclusion: The validated proposal will be an appropriate tool for mountain sports technicians to use in order to promote safety, reduce accidents and their consequent morbidity, and reduce the activation of rescue teams.
- Dataset on functional and chemical properties of the medicinal halophyte Polygonum maritimum L. under greenhouse cultivationPublication . Rodrigues, Maria Joao; Monteiro, Ivo; Placines, Chloé; Castañeda-Loaiza, Viana; Ślusarczyk, Sylwester; Matkowski, Adam; Pereira, Catarina; Pousão-Ferreira, Pedro; Custódio, LuísaThis data article includes data and analyses on the effect of different agronomic techniques on the production of Polygonum maritimum L. (sea knotgrass), namely different salinity irrigation treatments (0, 100, 200, 300 and 600 mM of NaCl) and a multi-harvest regime, and their relation with the chemical profile (ultra-high-resolution mass spectrometry - UHRMS), in vitro antioxidant [radical-scavenging activity (RSA) of DPPH and ABTS, copper chelating activity and ferric reducing antioxidant power] and anti-inflammatory (nitric oxide reduction on lipopolysaccharide-stimulated macrophages) activities. For further interpretation of the data presented in this work, please see the related research article "The irrigation salinity and harvesting affect the growth, chemical profile and biological activities of Polygonum maritimum L." (Rodrigues et al., 2019).
- Detection of emerging contaminants (UV filters, UV stabilizers and musks) in marine mussels from Portuguese coast by QuEChERS extraction and GC–MS/MSPublication . Picot Groz, M.; Martinez Bueno, M.J.; Rosain, D.; Fenet, H.; Casellas, C.; Pereira, Catarina; Maria, Vera L.; Bebianno, Maria João; Gomez, E.The UV filters and musk fragrances have come into focus because these compounds are contained and increasingly used not only in sunscreen products but also in many products of daily use, such as cosmetics, skin creams, plastics or varnish. In view of this, the main objective of the present work was to develop and validate a method for the determination of three UV filters, two UV stabilizers and four musks in mussel samples (Mytilus galloprovincialis). The procedure combined a QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) extraction method with an analysis by gas chromatography-tandem mass spectrometry (GC-MS/MS). The methodology allowed the determination of target analytes at trace concentration levels (ng/g), with mean recoveries ranging from 91 to 112%. A monitoring study was conducted in four beaches in the Portuguese coast which are impacted by recreational activities and outflow of treated waste water effluents in rivers. The results are used to assess the occurrence of UV filters in comparison with UV stabilizers and musk fragrances which indicate other activities than bathing.
- Effects of silver nanoparticles exposure in the mussel Mytilus galloprovincialisPublication . Gomes, Tânia; Pereira, Catarina; Cardoso, Cátia; Serrão Sousa, Vânia; Ribau Teixeira, Margarida; Pinheiro, José P.; Bebianno, Maria JoãoSilver nanoparticles (Ag NPs) have emerged as one of the most commonly used NPs in a wide range of industrial and commercial applications. This has caused increasing concern about their fate in the environment as well as uptake and potential toxicity towards aquatic organisms. Accordingly, mussels Mytilus galloprovincialis were exposed to 10 μg L(-1) of Ag NPs and ionic silver (Ag+) for 15 days, and biomarkers of oxidative stress and metal accumulation were determined. Accumulation results show that both Ag NPs and Ag+ accumulated in both gills and digestive glands. Antioxidant enzymes (superoxide dismutase, catalase and glutathione peroxidase) were activated by Ag NPs and Ag+, showing different antioxidant patterns in both gills and digestive glands. Moreover, metallothionein was inducted in gills, directly related to Ag accumulation, while in the digestive glands only a small fraction of Ag seems to be associated with this protein. Lipid peroxidation was higher in gills exposed to Ag NPs, whereas in the digestive glands only Ag+ induced lipid peroxidation. Ag NPs and Ag+ cause oxidative stress with distinct modes of action and it's not clear if for Ag NPs the observed effects are attributed to free Ag+ ions associated with the nanoparticle effect.
- Evaluation of sediment toxicity in different Portuguese estuaries: ecological impact of metals and polycyclic aromatic hydrocarbonsPublication . Serafim, M.A.; Company, Rui; Lopes, Belisandra; Pereira, Catarina; Cravo, Alexandra; Fonseca, V. F.; França, S.; Bebianno, Maria João; Cabral, H. N.Estuaries are exposed to multiple sources of different pollutants which tend to be trapped in sediments. Estuarine sediments can become reservoirs of contaminants that under certain circumstances may be released back to the water column, increasing their availability to the biota. Therefore, assessing sediment quality, of which toxicity testing is one of the lines-of-evidence, is a key element in ecological risk assessment strategies for these ecosystems. The use of Vibrio fischeri as luminescence bacteria is particularly effective in evaluating contaminated sediment. In this study, the ecotoxicity of sediments from five Portuguese estuaries (Aveiro, Tejo, Sado, Mira and Guadiana), was evaluated with a bioassay considering the 50% bioluminescence reduction of V. fischeri bacterium (EC50). Also, the levels of metals and polycyclic aromatic hydrocarbon contaminants (PAHs) were determined in the same sites. Moreover the Sediment Quality Guideline Quotient index (SQG-Q) was assessed for all sediments. The EC50 values varied significantly between estuaries but were strongly correlated with the metal concentrations in the different sites. In general Tejo estuary show higher toxicity levels compared to the other estuaries (5-min EC50 values of 5.6 mg mL(-1)). The integration of sediment contamination data shows that regarding the metallic contamination all sites are moderately impacted, with a higher SQG-Q in the Tejo estuary. On the other hand, when this index is applied to the PAHs levels, all sites are considered unimpacted. This suggests that metal contaminants are the most significant cause of toxicity in these sediments. Nevertheless, other factors can be relevant for this outcome due to the geochemical complexity of estuarine sediments (which affects contaminant speciation and bioavailability) and probably the presence of multiple xenobiotics in these sediments. (c) 2013 Elsevier Ltd. All rights reserved.
- Exploring the biotechnological value of marine invertebrates: a closer look at the biochemical and antioxidant properties of Sabella spallanzanii and Microcosmus squamigerPublication . Pan, Yu-Lun; Rodrigues, Maria João; Pereira, Catarina; Engrola, Sofia; Colen, R.; Mansinhos, Inês; Romano, Anabela; Andrade, Paula B.; Fernandes, Fátima; Custódio, LuísaSabella spallanzanii and Microcosmus squamiger were profiled for proximate composition, minerals, amino acids, fatty acids (FA), carotenoids, radical scavenging activity on the 2,2-diphenyl-1- picrylhydrazyl (DPPH) radical, oxygen radical absorbance capacity (ORAC) and iron and copper chelating properties. Microcosmus squamiger had the highest level of moisture and crude protein, S. spallanzanii was enriched in crude fat and ash. Both species had similar levels of carbohydrates and energy. There was a prevalence of arginine and glycine in S. spallanzanii, and of taurine in M. squamiger. The most abundant minerals in both species were Na, Ca, and K. The methanol extract of S. spallanzanii had metal chelating properties towards copper and iron, while the methanol extract of M. squamiger was able to chelate copper. M. squamiger extracts had similar ORAC values. Fucoxanthinol and fucoxanthin were the major carotenoids in the M. squamiger dichloromethane extract. Saturated FA were more abundant than unsaturated ones in methanol extracts, and unsaturated FA prevailed in the dichloromethane extracts. Palmitic acid was the predominant FA in methanol extracts, whereas eicosapentaenoic (EPA) and dihomo-γ-linolenic acids were the major compounds in dichloromethane extracts. Low n-6/n-3 ratios were obtained. Our results suggests that both species could be explored as sources of bioactive ingredients with multiple applications.
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