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Biblioteca Digital do IPB (53.442 recursos)

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BB - Resumos em Proceedings Não Indexados ao ISI

Mostrando recursos 1 - 20 de 536

  1. Alcachofra, borututu e cardo mariano: compostos bioativos, propriedades antioxidantes e hepatotoxicidade de infusões e suplementos dietéticos

    Pereira, Carla; Barros, Lillian; Calhelha, Ricardo C.; Ferreira, Isabel C.F.R.
    A alcachofra (Cynara scolymus L.), o borututu (Cochlospermum angolensis Welw.) e o cardo mariano (Silybum marianum (L.) Gaertn) são três plantas muito conhecidas pelo seu valor nutricional e utilizadas na medicina tradicional pelas suas propriedades antioxidantes e hepatoprotetoras [1-3]. No presente trabalho, estudaram-se infusões e suplementos dietéticos (na forma de comprimidos) das três plantas com o intuito de avaliar os seus compostos bioativos (fenóis e flavonóides totais), a atividade antioxidante (atividade captadora de radicais livres, poder redutor e inibição da peroxidação lipídica), a atividade anti-tumoral (linha de células tumorais humanas HepG2- carcinoma hepatocelular) e a hepatotoxicidade em culturas primárias células de fígado de porco- PLP2). Todas as amostras...

  2. Antioxidant properties of Pterospartum tridentatum (L.) Willk and Cymbopogon citratus (Dc) Stapf.: evaluation of synergistic effects in a mixture of these species

    Roriz, Custódio Lobo; Barros, Lillian; Carvalho, Ana Maria; Ferreira, Isabel C.F.R.
    The World Health Organization estimates that 80% of the world’s population uses medicinal plants in primary health needs. Pterospartum tridentatum (L.) Willk. (Fabaceae) and Cymbopogon citratus (DC) Stapf. (Poaceae) are examples of such medicinal plants. P. tridentatum is a small shrub, which can be found in the western part of the Iberian Peninsula and northern Morocco. Traditionally its flowers can be used to treat pneumonia, colds, bronchitis and hepatic disease [1]. C. citratus, commonly known as lemon grass, is a tall, aromatic, perennial densely tufted grass from Southeast Asia. There are many effects that can be attributed to this species, such as diuretics effects; it can also...

  3. Chemical composition of Morchella esculenta (L.) Pers. from Portugal and Serbia: A comparative study based on chromatographic techniques

    Heleno, Sandrina A.; Stojković, Dejan; Barreira, João C.M.; Glamočlija, Jasmina; Soković, Marina; Martins, Anabela; Queiroz, Maria João R.P.; Ferreira, Isabel C.F.R.
    Morchella esculenta (L.) Pers. (morel) is one of the most highly prized edible mushrooms in the world, revealing also interesting medicinal properties [1]. In the present work a comparative study on the chemical composition (nutritional value, primary and secondary metabolites) of two samples from different countries, Portugal (SP) and Serbia (SS), was performed based on chromatographic techniques [2]. Carbohydrates were the most abundant macronutrients, followed by proteins and ash. Fat contents were low and similar in both samples. The energetic contribution of SS was slightly higher due to the higher contribution of carbohydrates. Regarding sugars (analysed by HPLC-RI), mannitol and trehalose were found in both samples, but fructose was only...

  4. Potencial antioxidante dos compostos fenólicos de Helichrysum stoechas (L.) Moench para aplicações cosméticas: caracterização química, microencapsulação e incorporação num hidratante

    Barroso, Marisa; Barros, Lillian; Dueñas, Montserrat; Carvalho, Ana Maria; Santos-Buelga, Celestino; Fernandes, I.P.; Barreiro, M.F.; Ferreira, Isabel C.F.R.
    As propriedades bioativas de várias plantas têm sido atribuídas à presença de compostos fenólicos, especialmente flavonoides (Mishra et al., 2008). As propriedades biológicas, farmacológicas e medicinais deste grupo de compostos têm também sido exaustivamente estudadas (Marchand, 2002). Estudos etnobotânicos realizados no Nordeste de Portugal registam o uso da decocção de Helichrysum stoechas (L.) Moench (perpétua-das-areias ou douradinha) pelas suas propriedades medicinais nomeadamente no controlo da febre, sintomas gripais e bronquite (Carvalho, 2010). O presente trabalho teve como objetivo explorar o potencial antioxidante dos compostos fenólicos das sumidades floridas (capítulos e brácteas e os 15 cm terminais dos caules com folhas que suportam as inflorescências) de H. stoechas para...

  5. Extratos fenólicos de flores de Rubus ulmifolius Schoot: caracterização química, microencapsulação e incorporação em iogurtes para benefícios antioxidants

    Martins, Ana; Barros, Lillian; Carvalho, Ana Maria; Santos-Buelga, Celestino; Fernandes, I.P.; Barreiro, M.F.; Ferreira, Isabel C.F.R.
    Rubus ulmifolius Schoot (Rosaceae), conhecida como amora silvestre, é um arbusto perene encontrado em habitats silvestres e cultivados da Europa, Ásia e África do Norte. Tradicionalmente é conhecido pelas suas propriedades medicinais, incluindo atividade antioxidante. Neste trabalho caracterizaram-se quimicamente dois extratos fenólicos obtidos a partir de botões florais de R. ulmifolius, decocção e extrato hidroalcoólico, tendo sido identificados vários compostos fenólicos, maioritariamente derivados de elagitaninos nomeadamente, os isómeros sanguiin H-10 e lambertianina. Comparativamente à decocção, o extrato hidroalcoólico apresentou um conteúdo em compostos fenólicos superior e uma maior atividade antioxidante. A sua forma liofilizada foi a escolhida para microencapsular pela técnica de spray seguida de coagulação tendo-se produzido microesferas de...

  6. Propriedades nutricionais, químicas e bioativas de duas espécies de cogumelos silvestres do género Leccinum, provenientes do Nordeste Transmontano

    Vieira, Vanessa; Calhelha, Ricardo C.; Reis, Filipa S.; Barros, Lillian; Sousa, Maria João; Queiroz, Maria João R.P.; Martins, Anabela; Ferreira, Isabel C.F.R.
    Os cogumelos são muito apreciados, não apenas pelas suas propriedades organoléticas e nutricionais, mas também pelo seu potencial medicinal e capacidade de produção e acumulação de compostos bioativos. As suas propriedades antioxidantes e antitumorais têm sido amplamente documentadas, nomeadamente, pelo nosso grupo de investigação [1,2]. No entanto, das numerosas espécies que caracterizam a micoflora transmontana, existem ainda espécies pouco estudadas como é o caso de Leccinum molle (Bon) Bon e Leccinum vulpinum Watling. Assim sendo, o objetivo do presente trabalho foi caracterizar nutricional e quimicamente amostras silvestres das espécies referidas, em exemplares provenientes do nordeste transmontano (novembro, 2012). As propriedades antioxidantes e antitumorais dos...

  7. Avaliação da bioatividade e caracterização química de uma espécie de uso tópico: Juglans regia L.

    Santos, André; Barros, Lillian; Dueñas, Montserrat; Carvalho, Ana Maria; Santos-Buelga, Celestino; Ferreira, Isabel C.F.R.
    As folhas de Juglans regia L. (nogueira), são consideradas uma fonte de compostos benéficos para a saúde, sendo amplamente utilizadas na medicina tradicional. Alguns dos compostos bioativos presentes e, com maior destaque, são os compostos fenólicos (antioxidantes). No presente estudo, analisou-se a composição em ácidos orgânicos, mono e oligossacáridos, e tocoferóis nas folhas de nogueira e respetiva decocção (vulgarmente utilizada para aplicações tópicas). A composição fenólica e a bioatividade foram também avaliadas na decocção e no extracto metanólico. O ácido málico, a sacarose, o α-tocoferol e os ácidos 3-O-cafeoilquínicos e quercetina O-pentósido foram, respetivamente, o ácido orgânico, dissacárido, isoforma de tocoferol e compostos fenólicos, mais abundantes. O extrato...

  8. Caracterização das frações fenólica, polissacarídica e lipídica de cogumelos silvestres do Nordeste de Portugal

    Heleno, Sandrina A.; Barros, Lillian; Martins, Anabela; Queiroz, Maria João R.P.; Ferreira, Isabel C.F.R.
    O consumo de cogumelos tem vindo a aumentar consideravelmente pelas suas propriedades nutricionais (1) e medicinais (2) relacionadas com a presença de moléculas bioactivas que podem ser encontradas nas frações fenólica, polissacarídica e lipídica. Essas moléculas podem também ser encontradas em espécies não comestíveis e devidamente isoladas para utilização posterior. Neste trabalho, estudou-se a composição em compostos bioativos e a atividade antioxidante das frações mencionadas relativas a cinco espécies de cogumelos silvestres (Coprinopsis atramentaria, Lactarius bertillonii, Lactarius vellereus, Rhodotus palmatus e Xerocomus chrysenteron) (3). Os ácidos protocatéquico, p-hidroxibenzóico, p-cumárico e cinâmico foram identificados na fração fenólica. Os açúcares ramnose, xilose, fucose, arabinose, frutose, glucose, manose, manitol, sacarose, maltose e...

  9. Bioactivity of Methanolic and Aqueous Extracts of Laurus nobilis L. from Different Origins

    Dias, Maria Inês; Calhelha, Ricardo C.; Barreira, João C.M.; Queiroz, Maria João R.P.; Oliveira, M.B.P.P.; Soković, Marina; Ferreira, Isabel C.F.R.
    Laurus nobilis L. (Laureaceae), commonly known as laurel, is a native plant from the Mediterranean region. Most widely used as culinary spice, it is also consumed as infusion to treat some gastrointestinal problems (Dall’Acqua et al., 2009) and has been reported as a rich source of bioactive compounds namely, essential oils and phenolic compounds (Dadalioğlu et al., 2004; Dias et al., 2013). In the present work, methanolic and aqueous extracts of wild and cultivated L. nobilis were studied for their in vitro antitumor (against five different human tumor cell lines) and antimicrobial (antibacterial and antifungal) activities. Furthermore, a two-dimensional principal component analysis (PCA) was used to...

  10. Chromatographic analysis of the effects of gamma irradiation on organic acids composition of wild Boletus edulis and Hydnum repandum

    Fernandes, Ângela; Barreira, João C.M.; Antonio, Amilcar L.; Martins, Anabela; Oliveira, M.B.P.P.; Ferreira, Isabel C.F.R.
    The Northeast of Portugal is one of the European regions with higher wild edible mushrooms diversity, which are commonly collected for consumption for being a good source of digestible proteins, carbohydrates, fibers and vitamins. Recently, our research group developed a chromatographic methodology for analysis of organic acids in mushrooms [1]. These compounds play a determinant role in maintaining food quality and organoleptic characteristics (e.g., fruits and vegetables), and have also been used in quality control [2]. Moreover, the nature and concentration of organic acids are important factors in mushrooms flavor [3). The present work reports the use of the developed chromatographic methodology in the study of the effects of gamma...

  11. Antioxidant activity and phenolic compounds in decoction, infusion and hydroalcoholic extract of Origanum vulgare L.

    Martins, Natália; Barros, Lillian; Santos-Buelga, Celestino; Ferreira, Isabel C.F.R.
    Reactive species, including free radicals, have been implicated in ageing and various diseases [1]. The human body possesses an antioxidant defense system that acts in the detoxification and elimination of those species. Nevertheless, natural matrices can give an exogenous contribution, providing antioxidant biomolecules such is the case of phenolic compounds [2]. Origanum vu/gore L. (oregano) could be one of those matrices since various studies already reported the antioxidant potential of its methanolic extract [for example, 3] and essential oils [for example, 4]. Nonetheless, the reports using aqueous extracts are scarce [5], mainly in decoction or infusion preparations traditionally used to their digestive, expectorant, antiseptic and antispasmodic properties. In the present...

  12. Chemical composition, antimicrobial, antioxidant and cytotoxic activity of Rosa centifolia L. essential oil

    Nikolić, Miloš; Ferreira, Isabel C.F.R.; Calhelha, Ricardo C.; Fernandes, Ângela; Marković, Dejan; Marković, Tatjana; Ćirić, Ana; Glamočlija, Jasmina; Soković, Marina
    The genus Rosa comprises more than 200 species appreciated for their use in perfume and cosmetic industry. The aim of this study was to investigate chemical composition, antimicrobial, antioxidant and cytotoxic activities of Rosa centifolia L. essential oil, in an attempt to contribute to the use of this plant as alternative product for microbial control and cancer therapy. The results of GC/MS analysis showed the presence of 12 components. The major constituents were: phenyl ethyl alcohol (57 .71%), citronellol (21.61%), geraniol (12.09%). The rose oil showed strong antimicrobial activity inhibiting the growth of selected oral microorganisms (MIC 0.13-0.25 and MBC 0.25-0.50;...

  13. Anthocyanin profiles of Crataegus monogyna Jacq. fruits in different maturity stages

    Barreira, João C.M.; Rodrigues, Sandra; Dueñas, Montserrat; Carvalho, Ana Maria; Santos-Buelga, Celestino; Ferreira, Isabel C.F.R.
    The vast structural diversity of natural compounds found in plants provides unique opportunities for discovering new drugs. Anthocyanins are an example of bioactive compounds with possible beneficial effects on human health (/). Crataegus monogyna Jacq. (hawthorn) has been extensively studied due to its various alleged health benefits (2) . Herein, samples from fruits on three different maturity stages (unripe, ripened and over ripened fruits) were extracted with acidified (trifluoracetic acid) methanol. Extracts were purified on a C1s SepPak® Vac 3 cc cartridge (Phenomenex) and filtered through a 0.22-pm disposable LC filter disk. The HPLC system consisted of a 1-lewlett-Packard 1100 chromatograph (Agilent Technologies) with...

  14. Epidermal growth factor receptor inhibitory activity of new potential antitumor di(hetero)arylethers and di(hetero)arylamines in the thieno[3,2-b]pyridine series

    Calhelha, Ricardo C.; Peixoto, Daniela; Soares, Pedro; Ferreira, Isabel C.F.R.; Abreu, Rui M.V.; Queiroz, Maria João R.P.
    Thienopyridine skeleton has been reported as having interesting biological activity, namely as antitumorals [1] and antiangiogenics [2]. The Epidermal Growth Factor Receptor (EGFR) exists in the cell surface and is activated by binding its specific ligands. The inhibition of its intracellular tyrosine kinase domain prevents the signaling pathways of cellular proliferation [3]. In our research group we have prepared the di(hetero)arylethers 1a-f and the di(hetero)arylamines 2a-f functionalizing the 7-position of the thieno[3,2-b]pyridine in good to high yields, using copper (C-O) or palladium (C-N) catalyzed couplings, like presented below.The di(hetero)arylethers 1a-f and di(hetero)arylamines 2a-f series were evaluated for EGFR tyrosine kinase inhibition activity. Compounds for series 1 presented...

  15. Hydrophilic and lipophilic compounds in Arenaria montana L. and Chenopodium ambrosioides L. and bioactivity of their infusions and methanolic extracts

    Pereira, Eliana; Calhelha, Ricardo C.; Barros, Lillian; Carvalho, Ana Maria; Ferreira, Isabel C.F.R.
    Some plants traditionally used have medicinal properties with great potential for therapeutic applications in the treatment of some diseases since they are a natural source of bioactive compounds [1]. Arenaria Montana L. and Chenopodium ambrosioides L., commonly used in Portuguese folk medicine, are examples of those plants acting in the gastrointestinal tract, stomach, indigestion, respiratory system, flu, cold, vomiting, anthelmintics and in the healing of skin ulcers caused by Leishmania species; furthermore, they revealed anti-inflammatory and antitumor properties [2,3]. In this work, the chemical composition of the mentioned plants in hydrophilic (sugars and organic acids) and lipophilic (fatty acids and tocopherols) compounds was determined by chromatographic techniques....

  16. Chemical profile of Macrolepiota procera wild mushroom submitted to different processing technologies

    Fernandes, Ângela; Antonio, Amilcar L.; Oliveira, M.B.P.P.; Martins, Anabela; Ferreira, Isabel C.F.R.
    Mushrooms are very perishable food products and therefore tend to lose quality immediately after harvest. Extended shelf-life is an imperative factor to increase the profitability and availability of any food product, since it offers the possibility of developing markets at a greater distance [1,2]. Independently of the applied processing technology, any food product should retain the chemical and nutritional characteristics that typify its fresh form. In this work, the influence of freezing, drying and gamma-irradiating on the chemical parameters of Macrolepiota procera, one of the most appreciated wild mushrooms, was assessed through a principal component analysis. Fruiting bodies were obtained in Trás-os-Montes, in the Northeast of Portugal,...

  17. Protective effect of electron beam irradiation in tocopherols integrity: evaluation by HPLC-fluorescence detection

    Fernandes, Ângela; Barreira, João C.M.; Antonio, Amilcar L.; Martins, Anabela; Oliveira, M.B.P.P.; Ferreira, Isabel C.F.R.
    The high perishability is a common characteristic in mushrooms. This limitation demands for continuous investigation to achieve an effective conservation technology, allowing their preservation while simultaneously protecting the main bioactive compounds and the chemical composition in general. However, these two objectives might be more accurately achieved by combining two technologies, instead of using a single one. Therefore, electron-beam irradiation (up to 10 kGy) was applied to dried samples of Boletus edulis and Russula delica, increasing previous knowledge using gamma- and electron-beam irradiation at lower doses (up to 6 kGy) and different wild mushroom species. In this study, an HPLC system coupled to a fluorescence detector (FP-2020; Jasco), programmed for excitation...

  18. Efeito da radiação gama nas propriedades químicas de Boletus edulis Bull: Fr. silvestre

    Fernandes, Ângela; Barreira, João C.M.; Antonio, Amilcar L.; Oliveira, M.B.P.P.; Martins, Anabela; Ferreira, Isabel C.F.R.
    Boletus edulis Bull: Fr. (comumente designado níscaro) é um cogumelo comestível bastante apreciado pelas suas propriedades organoléticas e nutricionais. No entanto, a sua sazonalidade e perecibilidade causam algumas dificuldades na distribuição e comercialização desta espécie em fresco; as perdas associadas a este tipo de alimentos durante a comercialização podem chegar aos 40% (Lacroix & Ouattara, 2000). Tem havido muita investigação no sentido de encontrar tecnologias que garantam a preservação dos cogumelos, mantendo as suas propriedades organoléticas e nutricionais por mais tempo. A irradiação é reconhecida como um método seguro e eficaz para a preservação de alimentos, sendo utilizada mundialmente para aumentar o tempo de prateleira de produtos...

  19. Inhibitory activity of Coprinopsis atramentaria extract, organic acids and their possible methylated synthesized metabolites on growth of human tumor cell lines

    Heleno, Sandrina A.; Ferreira, Isabel C.F.R.; Calhelha, Ricardo C.; Martins, Anabela; Queiroz, Maria João R.P.
    Coprinopsis atramentaria (Bull.: Fr.) Redhead. Vilgalys & Moncalvo, is a wild edible mushroom previously characterized by our research group for its nutritional composition, and showed a notable antioxidant activity. p-Hydroxybenzoic (4. 71 mg/1 00 g dry weight), p coumaric (0.82 mg/ 100 g) and cinnamic (1.70 mg/100 g) acids were identified in its extract, but have been reported as common compounds in other mushrooms. In the present work, the inhibitory activity of the growth of human tumor cell lines MCF-7 (breast adenocarcinoma), NCl-H460 (non-small cell lung carcinoma), HCT 15 (colon carcinoma). 1-lcLa (cervical carcinoma) and l-l epG2 (hepatocellular carcinoma) and non-tumor porcine...

  20. Effects of gamma irradiation in Castanea sativa tocopherols profile: study extended to four different chestnut varieties

    Carocho, Márcio; Antonio, Amilcar L.; Barreira, João C.M.; Botelho, M. Luísa; Bento, Albino; Ferreira, Isabel C.F.R.
    In the region of Trás-os-Montes, chestnut production represents a significant income, estimated to be about 15 M€ in 2010. It is therefore, mandatory to develop a safe, reliable and cheap disinfestation alternative to post-harvest fumigation with methyl bromide, since its eradication in 2010 by the European Union, due to environmental concerns and danger for the operators. Hot water dip is being used as a replacement, but still display considerable technical disadvantages, giving way to other alternatives like irradiation. Today, many food commodities (e.g. frog legs, spices, mushrooms) are irradiated in Europe with strict regulation and no health issues reported [1]. Tocopherols represent the isoforms of vitamin E, which are known for their excellent antioxidant activity, either alone or in synergy with...

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