Browsing by Author "Pereira, Catarina Guerreiro"
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- Accumulation and toxicity of copper oxide nanoparticles in the digestive gland of Mytilus galloprovincialisPublication . Gomes, Tânia; Pereira, Catarina Guerreiro; Cardoso, Cátia; Pinheiro, José Paulo; Cancio, I.; Bebianno, Maria JoãoGiven the wide use of CuO nanoparticles in various industrial and commercial applications they will inevitably end up in the aquatic environment. However, little information exists on their biological effects in bivalve species. Accordingly, mussels Mytilus galloprovincialis were exposed to 10 g Cu L−1 as CuO nanoparticles and Cu2+ for 15 days, and biomarkers of oxidative stress (superoxide dismutase, catalase and glutathione peroxidase), damage (lipid peroxidation) and metal exposure (metallothionein) were determined along with Cu accumulation in the digestive glands of mussels. Cu was linearly accumulated with time of exposure in mussels exposed to CuO nanoparticles, while in those exposed to Cu2+ elimination was significant by day 15. Both forms of Cu cause oxidative stress with distinct modes of action. Exposure to CuO nanoparticles induces lower SOD activity in digestive glands compared to those exposed to Cu2+, while CAT was only activated after 7 days of exposure to nano and ionic Cu, with contradictory effects after 15 days of exposure and GPX activities were similar. Lipid peroxidation levels increased in both Cu forms despite different antioxidant efficiency. Moreover, a linear induction of metallothionein was detected with time in mussels exposed to CuO nanoparticles, directly related to Cu accumulation, whereas in those exposed to Cu2+ metallothionein was only induced after 15 days of exposure. Since only a small fraction of soluble Cu fraction was released from CuO nanoparticles, the observed effects seem to be related to the nano form of Cu, with aggregation as a key factor. Overall, our results show that the digestive gland is susceptible to CuO nanoparticles related oxidative stress, and is also the main tissue for their accumulation.
- Chemical profiling of infusions and decoctions of Helichrysum italicum subsp picardii by UHPLC-PDA-MS and in vitro biological activities comparatively with green tea (Camellia sinensis) and rooibos tisane (Aspalathus linearis)Publication . Pereira, Catarina Guerreiro; Barreira, Luísa; Bijttebier, Sebastiaan; Pieters, Luc; Neves, Vanessa; Rodrigues, Maria João; Rivas, Ricardo; J. C. or Varela J. or Varela J.C.S., Varela; Custódio, LuísaSeveral medicinal plants are currently used by the food industry as functional additives, for example botanical extracts in herbal drinks. Moreover, the scientific community has recently begun focusing on halophytes as sources of functional beverages. Helichrysum italicum subsp. picardii (everlasting) is an aromatic halophyte common in southern Europe frequently used as spice and in traditional medicine. In this context, this work explored for the first time H. italicum subsp. picardii as a potential source of innovative herbal beverages with potential health promoting properties. For that purpose, infusions and decoctions were prepared from roots, vegetative aerial-organs (stems and leaves) and flowers and evaluated for in vitro antioxidant and anti-diabetic activities. Samples were also assessed for toxicity in different mammalian cell lines and chemically characterized by spectrophotometric methods and ultra-high performance liquid chromatography photo diode array mass-spectrometry (UHPLC-PDA-MS). Results were expressed relating to 'a cup-of-tea' and compared with those obtained with green tea (Camellia sinensis) and rooibos tisane (Aspalathus linearis). Tisanes from the everlasting's above-ground organs, particularly flowers, have high polyphenolic content and several phenolics were identified; the main compounds were chlorogenic and quinic acids, dicaffeoylquinic-acid isomers and gnaphaliin-A. The antioxidant activity of beverages from the everlasting's above-ground organs matched or surpassed that of green tea and rooibos. Its anti-diabetic activity was moderate and toxicity low. Overall, our results suggest that the everlasting is a potential source of innovative and functional herbal beverages. (C) 2017 Elsevier B.V. All rights reserved.
- Effects of copper nanoparticles exposure in the mussel Mytilus galloprovincialisPublication . Gomes, Tânia; Pinheiro, J. P.; Cancio, I.; Pereira, Catarina Guerreiro; Cardoso, Cátia; Bebianno, Maria JoãoCuO NPs are widely used in various industrial and commercial applications. However, little is known about their potential toxicity or fate in the environment. In this study the effects of copper nanoparticles were investigated in the gills of mussels Mytilus galloprovincialis, comparative to Cu(2+). Mussels were exposed to 10 μg Cu·L(-1) of CuO NPs and Cu(2+) for 15 days, and biomarkers of oxidative stress, metal exposure and neurotoxicity evaluated. Results show that mussels accumulated copper in gills and responded differently to CuO NPs and Cu(2+), suggesting distinct modes of action. CuO NPs induced oxidative stress in mussels by overwhelming gills antioxidant defense system, while for Cu(2+) enzymatic activities remained unchanged or increased. CuO NPs and Cu(2+) originated lipid peroxidation in mussels despite different antioxidant efficiency. Moreover, an induction of MT was detected throughout the exposure in mussels exposed to nano and ionic Cu, more evident in CuO NPs exposure. Neurotoxic effects reflected as AChE inhibition were only detected at the end of the exposure period for both forms of copper. In overall, these findings show that filter-feeding organisms are significant targets for nanoparticle exposure and need to be included when evaluating the overall toxicological impact of nanoparticles in the aquatic environment.
- Estudo de ALP como biomarcador de disrupção endócrina em Mytilus galloprovincialisPublication . Pereira, Catarina Guerreiro; Cravo, AlexandraA wide range of compounds, continuously released into the aquatic environment and present in complex mixtures, are able to interfere with the endocrine system of organisms causing adverse effects on various levels. These chemicals, named ?endocrine disrupting compounds? (EDCs), include both natural and synthetic estrogens, as well as a variety of estrogen-mimicking chemicals (xenoestrogens). Such compounds include both natural (ex: estradiol) and synthetic (ex: ethinylestradiol) estrogens, synthetic estrogenic compounds associated with detergents (ex: nonylphenol), plasticisers (ex: bisphenol A), metals, as well as phytoestrogens, pesticides and polychlorinated biphenyls (PCBs). These are usually associated with municipal and industrial wastewater discharges, and were detected in freshwater, estuarine and marine environments, thus representing a potential hazard for aquatic species. Bivalves are important and abundant species of the aquatic ecosystems and susceptible to suffer endocrine disruption. Xenoestrogens can affect particularly the reproductive functions through the induction of vitellogenin-like (Vtg-like) proteins, which are precursors of energetic reserves in embryonic development. These proteins are typically associated to females, presenting low levels in males and juveniles. Hence, they have been proposed has a biomarker of endocrine disruption. Recently, the levels of Vtg-like proteins were quantified in bivalves by an indirect method such as the Alkali-labile Phosphates (ALP) assay. Several studies have proved its viability as a biomarker of ED, revealing higher ALP concentrations especially in males and immature females, indicative of the presence of environmental estrogens. The aim of this study was to evaluate the presence of EDCs in the south coast of Portugal, specifically in harbours, marinas and main estuaries areas, using Vtg-like proteins as a biomarker of exposure to xenoestrogenic compounds in mussels, through the use of the ALP assay in female and male gonads of Mytilus galloprovincialis. Mussels were sampled at eight sites along the Algarve coastal zone, in the vicinity of the major urban areas, in comparison with mussels from a beach less exposed in terms of anthropogenic influence. Results indicate spatial and seasonal variability, and females showed generally higher ALP concentrations than males. Mussels from Sagres (88.4?12.9?gPO
- From threat to opportunity: Harnessing the invasive Carpobrotus edulis (L.) N.E.Br for nutritional and phytotherapeutic valorization amid seasonal and spatial variabilityPublication . Pereira, Catarina Guerreiro; Neng, Nuno R.; Custódio, LuísaCarpobrotus edulis (L.) N.E.Br. (Hottentot-fig) is a problematic invasive species found in coastal areas worldwide. Mechanical removal is a common control method, leaving the removed biomass available as a possible source of natural phytochemicals with prospective commercial applications. While the Hottentot-fig’s vegetative organs have been studied previously, this work establishes for the first time a seasonal and spatial comparative analysis of its nutritional, chemical, and bioactivity profiles (in three locations over four seasons). Proximate and mineral contents were assessed, along with its phenolic composition and in vitro antioxidant and anti-inflammatory properties. Hottentot-fig’s biomass offered a good supply of nutrients, mainly carbohydrates, proteins, and minerals, with a tendency for higher concentrations of the most relevant minerals and proteins in autumn and winter, and in plants from sites A (Ria de Alvor lagoon) and B (Ancão beach). The extracts were rich in polyphenolics, with higher levels in spring and summer, especially for luteolin7-O-glucoside and salicylic and coumaric acids. The extracts were also effective antioxidants, with stronger radical scavenging activities in spring and summer, along with anti-inflammatory properties. Our results suggest that the usually discarded plant material of this invasive halophyte could be valuable as a source of natural products with potential biotechnological applications in the food and nutraceutical industries.
- Halophyte plants as potential sources of Anticancer agents: a comprehensive reviewPublication . Custódio, Luísa; Garcia-Caparros, Pedro; Pereira, Catarina Guerreiro; Castelo-Branco, PedroSalt-tolerant plants (halophytes) are widely distributed worldwide in several environments such as coastal salt marshes, sand dunes, and inland deserts. To cope with the harsh conditions that characterize those habitats, which include high salinity and radiation levels, such plants have developed morphological and physiological traits, the latter including the synthesis and accumulation of important secondary metabolites such as alkaloids and polyphenols. While essential in maintaining plant homeostasis, these compounds are highly valued in the medical field for the treatment of several human diseases, including cancer. Cancer is one of the most life-threatening disorders worldwide, which accentuates the need to improve current cancer therapies and minimize potential adverse secondary side-effects. In this context, the pharmacological evaluation of natural compounds has attracted growing interest since nature has already provided some important anti-cancer drugs. This review compiles, for the first time, research regarding the anticancer activity of halophytes from different families, including, whenever possible, the bioactive molecules involved in such therapeutical properties along with possible mechanisms of action. The introduction section provides some pertinent information regarding cancer and a summary of the most important characteristics of halophytes. The next section gives information regarding the in vitro and in vivo cytotoxic properties of several halophyte species, grouped by families, including contents in bioactive metabolites and proposed modes of action, if possible. Lastly, the conclusion presents the most relevant metabolites and/or promising species and extracts that could be further explored in anticancer drug research.
- In vitro anti-trypanosoma cruzi activity of halophytes from Southern Portugal reloaded: a special focus on Sea Fennel (Crithmum maritimum L.)Publication . Pereira, Catarina Guerreiro; Moraes, Carolina Borsoi; Franco, Caio H.; Feltrin, Clarissa; Grougnet, Raphaël; Barbosa, Euzébio Guimarães; Panciera, Michele; Correia, Carlos Roque D.; Rodrigues, Maria Joao; L, CustódioMarine halophytes are an outstanding reservoir of natural products and several species have anti-infectious traditional uses. However, reports about their potential use against neglected tropical ailments, such as Chagas disease, are scarce. This work evaluated for the first time the in vitro anti-Trypanosoma cruzi activity of extracts from the aromatic and medicinal species Helichrysum italicum subsp. picardii (Boiss. & Reut.) Franco (Asteraceae, everlasting) and Crithmum maritimum L. (Apiaceae, sea fennel). For that purpose, decoctions, tinctures, and essential oils from everlasting’s flowers and sea fennel’s stems, leaves, and flowers were tested against intracellular amastigotes of two T. cruzi strains. The extract from the sea fennel flower decoction displayed significant anti-trypanosomal activity and no toxicity towards the host cell (EC50 = 17.7 µg/mL, selectivity index > 5.65). Subsequent fractionation of this extract afforded 5 fractions that were re-tested in the same model of anti-parasitic activity. Fraction 1 was the most active and selective (EC50 = 0.47 µg/mL, selectivity index = 59.6) and was submitted to preparative thin-layer chromatography. One major compound was identified, falcarindiol, which was likely the one responsible for the observed antitrypanosomal activity. This was confirmed using a commercially sourced molecule. Target-fishing studies showed falcarindiol as a ligand of T. cruzi spermidine synthase, pointing to a potential enzyme-inhibiting anti-trypanosomal mechanism of action. Overall, this work shows that sea fennel can provide effective anti-parasitic molecule(s) with potential pharmacological applications in the treatment of CD.
- New insights into the phytochemical profile and biological properties of Lycium intricatum Bois. (Solanaceae)Publication . Bendjedou, Houaria; Benamar, Houari; Bennaceur, Malika; Rodrigues, Maria João; Pereira, Catarina Guerreiro; Trentin, Riccardo; L, CustódioThis work aimed to boost the valorisation of Lycium intricatum Boiss. L. as a source of high added value bioproducts. For that purpose, leaves and root ethanol extracts and fractions (chloroform, ethyl acetate, n-butanol, and water) were prepared and evaluated for radical scavenging activity (RSA) on 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,20 -azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radicals, ferric reducing antioxidant power (FRAP), and metal chelating potential against copper and iron ions. Extracts were also appraised for in vitro inhibition of enzymes implicated on the onset of neurological diseases (acetylcholinesterase: AChE and butyrylcholinesterase: BuChE), type-2 diabetes mellitus (T2DM, α-glucosidase), obesity/acne (lipase), and skin hyperpigmentation/food oxidation (tyrosinase). The total content of phenolics (TPC), flavonoids (TFC), and hydrolysable tannins (THTC) was evaluated by colorimetric methods, while the phenolic profile was determined by high-performance liquid chromatography, coupled to a diode-array ultraviolet detector (HPLCUV-DAD). Extracts had significant RSA and FRAP, and moderate copper chelation, but no iron chelating capacity. Samples had a higher activity towards α-glucosidase and tyrosinase, especially those from roots, a low capacity to inhibit AChE, and no activity towards BuChE and lipase. The ethyl acetate fraction of roots had the highest TPC and THTC, whereas the ethyl acetate fraction of leaves had the highest flavonoid levels. Gallic, gentisic, ferulic, and trans-cinnamic acids were identified in both organs. The results suggest that L. intricatum is a promising source of bioactive compounds with food, pharmaceutical, and biomedical applications.
- Nutritional and phyto-therapeutic value of the Halophyte Cladium mariscus L. (Pohl.): a special focus on seedsPublication . Rodrigues, Maria João; L, Custódio; Mecha, Débora; Zengin, Gokhan; Cziáky, Zoltán; Sotkó, Gyula; Pereira, Catarina GuerreiroThis work searched for the phyto-therapeutic potential and nutritional value of seeds from the halophyte Cladium mariscus L. (Pohl.), aiming at its use as a source of bioactive ingredients for the food industry. Hence, the nutritional profile, including minerals, of seeds biomass was determined; food-grade samples were prepared, and their phytochemical fingerprinting assessed. Extracts were evaluated for in vitro antioxidant potential, inhibitory capacity towards enzymes related to neuroprotection, diabetes, and hyperpigmentation, and anti-inflammatory properties, along with a toxicological assessment. Sawgrass seeds can be considered a proper nutritional source with a good supply of minerals. All extracts had a high level of total phenolics (65.3–394.4 mg GAE/g DW) and showed a chemically rich and diverse profile of metabolites that have several biological properties described (e.g., antioxidant, anti-inflammatory). Extracts had no significant toxicity (cell viabilities > 80%) and were overall strong antioxidants (particularly at radical scavenging and reducing iron), effective tyrosinase inhibitors (55–71 mg KAE/g DW), showed anti-inflammatory properties (30–60% NO decrease), and had moderate capacity to inhibit enzymes related to neuroprotection (AChE 3.7–4.2, BChE 4.3–6.0 mg GALE/g DW) and diabetes (α-glucosidase 1.0–1.1, α-amylase 0.8–1.1 mmol ACAE/g). Altogether, results suggest that sawgrass seeds have the potential to be exploited as a new food product and are a reservoir of bioactive molecules with prospective applications as ingredients for value-added, functional, and/or preservative food products
- A review on sarcocornia species: Ethnopharmacology, nutritional properties, phytochemistry, biological activities and propagationPublication . Custódio, Luísa; Rodrigues, Maria João; Pereira, Catarina Guerreiro; Castañeda-Loaiza, Viana; Fernandes, Eliana; Standing, Dominic; Neori, Amir; Shpigel, Muki; Sagi, MosheSarcocornia A. J. Scott is a halophytic edible succulent plant belonging to the Amaranthaceae family. To date, the genus includes 28 species distributed worldwide in saline environments, usually salt marshes. Sarcocornia (Scott) is similar to Salicornia (L.), which has a recognized commercial value in morphological and taxonomical traits. Species of both genera are commonly named samphire or glassworts in Europe, and their fleshy shoots are commercialized under their traditional names. Due to their nutritional, organoleptic and medicinal properties, Sarcocornia species have a high economic potential in various biotechnology sectors. Being highly tolerant to salt, they can be cultivated in saline conditions, and dissimilar to Salicornia, they are perennial, i.e., they can be harvested year-round. Therefore, Sarcocornia species are considered promising gourmet vegetables to be explored in the context of climate change, soil and water salinization and eco-sustainability. We hereby put together and reviewed the most relevant information on Sarcocornia taxonomy, morphology, nutritional and pharmacological properties, uses in ethnomedicine, potential applications in biotechnology, and propagation strategies.