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- New perspectives of Juglans regia L. phytochemicals against Candida speciesPublication . Martins, Natália; Barros, Lillian; Carvalho, Ana Maria; Silva, Sónia; Henriques, Mariana; Ferreira, Isabel C.F.R.Opportunistic fungal infections have deserved special relevance in the last decades, presenting itself, a serious problem in terms of public health. Despite Candida albicans was considered the main agent responsible for those infections, other non-albicans Candida species have also been described in the last years [1-3]. Most of the species are susceptible to antimicrobial drugs, but recently it has been observed a growing number of microorganisms with drug resistance. Therefore, the discover/use of alternative therapies is crucial [4]. Juglans regia L. (walnut) leaves are commonly used in traditional medicine as antiseptic, antimicrobial and anti-inflammatory [5]; those benefits could be related with its richness in phenolic compounds [6]. In the present work, the antifungal potential of the hydroalcoholic extract prepared from walnut leaves was evaluated against a total of nineteen Candida strains (from the species: C.albicans, C.glabrata, C.parapsilosis and C.tropicalis), using the disc diffusion halo assay. All the tested strains were sensible to the plant extract. The obtained values of the inhibitory zones ranged between 0.9-1.4 cm, being the halo maintained after 48h. The observed antifungal activity is certainly related to the phenolic compounds previously determined in the extract [6]: five phenolic acid derivativescaffeoylquinic and p-coumaroylquinic acid derivatives, two dimers and one trimer of procyanidins, twelve flavonols- quercetin, myricetin and kaempferol derivatives, and five taxifolin O-pentoside isomers; 3-Ocaffeoylquinic acids and quercetin O-pentoside were the main phenolic compounds. Further studies are necessaries in order to elucidate the most active compounds and the specific role of each one.
- Diversidade nutricional de acessos de tomate de mesa das regiões Centro e Norte de PortugalPublication . Pereira, Alexis; Añibarro-Ortega, Mikel; Rocha, Filomena; Lopes, V. Rolim; Carvalho, Ana Maria; Barata, Ana Maria; Barros, Lillian; Pinela, JoséO tomate (Solanum lycopersicum L.) é uma das culturas hortícolas mais importantes em todo o mundo e desempenha um papel fundamental na dieta mediterrânica. Ao longo dos anos, o cultivo de tomate em sistemas agrícolas extensivos, como hortas e quintais, levou ao surgimento de várias variedades tradicionais com características morfológicas e sensoriais distintas. Estas variedades representam um valioso reservatório de diversidade genética que deve ser preservado. No entanto, há uma escassez de dados na literatura que relacionem as características morfológicas do tomate com diferenças na sua composição. O objetivo deste estudo foi caraterizar a diversidade nutricional de acessos de tomate de mesa originários das regiões Centro e Norte de Portugal, atualmente conservados no Banco Português de Germoplasma Vegetal. Para isso, foram selecionados vários acessos de tomate conhecidos localmente como "comum," "coração-de-boi," "pequenino," "rasteiro" e "miúdo". Estes acessos foram regenerados em campos experimentais, sob as mesmas condições edafoclimáticas, para obter frutos maduros para análise e reposição de sementes. Os frutos foram analisados quanto à sua composição centesimal, incluindo os teores de humidade, proteína, gordura, cinzas e hidratos de carbono, utilizando métodos analíticos oficiais para alimentos. Os perfis individuais de açúcares livres, ácidos orgânicos, ácidos gordos e tocoferóis foram caraterizados por meio de diferentes técnicas cromatográficas. Os carotenoides licopeno e β-caroteno foram quantificados utilizando um método espetrofotométrico. Os resultados destas análises contribuíram para uma compreensão abrangente sobre as características nutricionais dos acessos de tomate de mesa selecionados e com origem nas regiões Centro e Norte de Portugal
- Tocopherol composition and antioxidant activity of Spanish wild vegetablesPublication . Morales, Patricia; Carvalho, Ana Maria; Sánchez Mata, María de Cortés; Cámara Hurtado, Montaña; Molina, María; Ferreira, Isabel C.F.R.Traditional use of noncultivated vegetables has decreased with the development of agriculture and global supply chains. However, some species are still consumed as part of our traditional Mediterranean diet. Plants are among the most important sources of natural antioxidants for retarding lipid oxidative rancidity in foods or for pharmaceutical applications against chronic diseases related to free radicals production. The present study reports tocopherols composition and antioxidant activity of eight wild greens traditionally used in Spain. According to the edible part consumed, two groups were differentiated. Leafy vegetables whose young stems with leaves are consumed (Apium nodiflorum (L.) Lag., Foeniculum vulgare Mill., Montia fontana L. and Silene vulgaris (Moench) Garcke), and wild asparagus whose young shoots with leaf buds scarcely developed are eaten (Asparagus acutifolius L., Bryonia dioica Jacq., Humulus lupulus L. and Tamus communis L.). Among the leafy vegetables, Silene vulgaris and Apium nodiflorum presented the highest antioxidant capacity and antioxidants contents. Among the wild asparagus, the highest antioxidant capacity was obtained in Humulus lupulus.
- Composition in anthocyanins of wild fruits from Northeastern PortugalPublication . Guimarães, Rafaela; Barros, Lillian; Dueñas, Montserrat; Carvalho, Ana Maria; Queiroz, Maria João R.P.; Santos-Buelga, Celestino; Ferreira, Isabel C.F.R.Flavonoids represent the most common and widely distributed group of plant phenolic compounds, and can be further broken into classes including flavones, flavonols, flavanones, flavanols, isoflavonoids and anthocyanins (1). Anthocyanins are widespread in nature mainly in flowers, fruits and vegetables and are responsible for their orange, red and blue colors. They are nontoxic, water-soluble compounds of great interest in nutrition and medicine because of their potent antioxidant capacity (2) , ability to regulate adipocytokine gene expression (3), and therefore, possible protective effects on human health ( 4). They are also used in dyes industry to rep lace synthetic pigments by natural ones (5). This study aimed to analyze the composition in anthocyanins of wild fruits of Arbutus unedo L. (strawberry-tree), Prunus spinosa L. (b lackthorn), Rosa canina L. and Rosa micrantha Borrer ex Sm. (wild roses) from northeastern Portugal. The fruits were extracted using methanol with 0.5% trilluoracetic acid, puritied with a C-1 8 SepPak® cartridge and analyzed by 1-lPLC-DAD-ESI/MS. Cyanidin 3-0-glucoside was found in all the studied fruits, being the major anthocyanin in most of them, with the exception of P. spinosa sample, in which cyanidin-3-0-rutinoside and peonidin-3-0-rutinoside predominated. P . spinosa sample presented the more complex anthocyanin profile among the analyzed fruits and also the highest anthocyanin concentrations (100.40 ~-L g/ 100 g dry weight), which was coherent with its greater pigmentation. R. canina fruits presented the lowest concentration (0.68 11 g/ l 00 g) . Overall, the studied fruits may have great potential for food industries as a source of colors and flavors, as well as bioactive molecules for dietary supplements or functional foods .
- Antioxidant potential of wild food plantsPublication . Barros, Lillian; Morales, Patricia; Carvalho, Ana Maria; Ferreira, Isabel C.F.R.A free radical is defined as any species containing one or more unpaired electrons (electrons singly occupying an atomic or molecular orbital), whereas reactive species is the collective term for radicals and some other non-radical derivatives of oxygen, nitrogen, or sulfur that can easily generate free radicals and/or cause oxidative damage (Halliwell 2012). As shown in Table 10.1, reactive oxygen species (ROS) include free radicals such as hydroperoxyl radical (HO2), superoxide anion radical (O2−), hydroxyl radical (HO) and peroxyl radical (ROO; e.g., lipid derived), and other species such as hydrogen peroxide (H2O2), singlet oxygen (1O2), hypochlorous acid (HOCl), and peroxide (ROOR; Lü et al. 2010; Carocho and Ferreira 2013).
- Valorisation of tomato wastes for development of nutrient-rich antioxidant ingredients: A sustainable approach towards the needs of the today's societyPublication . Pinela, José; Prieto Lage, Miguel A.; Barreiro, M.F.; Carvalho, Ana Maria; Oliveira, Beatriz; Curran, Thomas P.; Ferreira, Isabel C.F.R.Nutrient-rich antioxidant ingredients were produced from tomato fruit wastes using a microwave-assisted extraction (MAE) process. Different conditions of extraction time (t), temperature (T), ethanol concentration (Et) and solid/liquid ratio (S/L) were combined in a circumscribed central composite design and optimized by response surface methodology. The model was statistically validated and used for prediction in the experimental range. Under the global optimal MAE conditions (t = 20 min, T = 180 °C, Et = 47.4% and S/L = 45 g/L), it was possible to obtain an extraction yield of 75.5% and ingredients with high levels of sugars, proteins, phenolics, and flavonoids, and interesting antioxidant properties measured via ABTS[rad] + scavenging activity and oxidative haemolysis inhibition assay (OxHLIA). The antioxidant capacity of the extracts was lower compared to the one of commercial food additives. However, the sustainably developed ingredients may be used in the fortification and functionalisation of food, as well as for incorporation in feed products. Industrial relevance This study addresses current needs of the agri-food sector, namely the recycling of plant wastes and production of valuable extracts for the food/feed industry. A MAE process was developed and optimized to maximize the recovery of nutrients and antioxidants from tomato fruit wastes. The optimum processing conditions established in this study allowed a high extraction yield and reduced solvent consumption. MAE can be considered as a sustainable alternative to conventional extraction methods. These findings will contribute to promote a more sustainable bioeconomy in the agro-food sector.
- Nutritional and nutraceutical potential of rape (Brassica napus L. Var. napus) and "tronchuda" cabbage (Brassica oleraceae L. Var. costata) inflorescencesPublication . Batista, Cátia Emanuela Oliveira; Barros, Lillian; Carvalho, Ana Maria; Ferreira, Isabel C.F.R.Two traditional cultivated vegetables highly consumed among Northern Portuguese regions were tested for their chemical composition, nutritional profile and in vitro antioxidant properties using four assays: 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radicals scavenging activity, reducing power, inhibition of -carotene bleaching and inhibition of lipid peroxidation by thiobarbituric acid reactive substances (TBARS) assay. The studied varieties of two Brassica species, locally known as “grelos” (rape) and “espigos” (“tronchuda” cabbage) are nutritionally well-balanced vegetables; particularly “tronchuda” cabbage revealed the highest levels of moisture, proteins, fat, energy, β-carotene and vitamin C; rape gave the highest contents of ash, carbohydrates, sugars (including fructose, glucose, sucrose and raffinose), essential n-3 fatty acid α-linolenic acid, and the best ratios of PUFA/SFA and n-6/n-3 fatty acids, tocopherols, lycopene, chlorophylls, phenolics, flavonoids, and also the highest antioxidant properties. The health benefits associated to the antioxidant properties reinforce their contribution to a healthy and balanced diet, highlight the interest of their consumption, validate the empirical use and add new values to traditional/regional products which have been used for a long time.
- Bioactivity of different enriched phenolic extracts of wild fruits from Northeastern Portugal: a comparative studyPublication . Guimarães, Rafaela; Barros, Lillian; Calhelha, Ricardo C.; Carvalho, Ana Maria; Queiroz, Maria João R.P.; Ferreira, Isabel C.F.R.Arbutus unedo, Prunus spinosa, Rosa micrantha and Rosa canina are good sources of phenolic compounds, including anthocyanins. These compounds have potent antioxidant properties, which have been related to anticancer activity. Herein, the in vitro antioxidant and antitumor properties of enriched phenolic extracts (non-anthocyanin phenolic compounds enriched extract- PE and anthocyanins enriched extract- AE) of the mentioned wild fruits were evaluated and compared. PE gave higher bioactive properties than the corresponding AE. It was observed a high capacity of A. unedo phenolic extract to inhibit lipid peroxidation in animal brain homogenates (EC50 = 7.21 µg/mL), as also a high antitumor potential against NCI-H460 human cell line (non-small lung cancer; GI50 = 37.68 µg/mL), which could be related to the presence of galloyl derivatives (exclusively found in this species). The bioactivity of the studied wild fruits proved to be more related to the phenolic compounds profile than to the amounts present in each extract, and could be considered in the design of new formulations of dietary supplements or functional foods.
- Antioxidant properties of Pterospartum tridentatum (L.) Willk and Cymbopogon citratus (Dc) Stapf.: evaluation of synergistic effects in a mixture of these speciesPublication . 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 be used in hepatic disorders and to treat depression, flatulence and intestinal cramps [2]. The mixture of these two species opens a new panoply of therapeutic effects that can range from the treatment in case of stomach pain, cramping and flatulence, diarrhea, vomiting and flu. This is due to the interaction of these two species. In this study we aimed to evaluate the antioxidant activity of the single plants and of the mixture of the same plants (infusions and methanolic extracts. The antioxidant activity was accessed by four in vitro assays: scavenging effects on DPPH (2,2-diphenyl-1-picrylhydrazyl) radicals, reducing power, inhibition of β-carotene bleaching and inhibition of lipid peroxidation in brain cell homogenates by TBARS (thiobarbituric acid reactive substances) assay. In general, infusions revealed higher antioxidant activity than methanolic extracts, being higher for P. tridentatum. With the exception of the β-carotene bleaching inhibition assay, the mixture of the two plants revealed significant synergistic effects, allowing higher antioxidant activity. Although the interesting results obtained, the authors recommend a safe consume of these plant materials, including restricting the dose and duration of use to minimize the risks of potentially interactions with conventional medicines. Further studies will be conducted in order to identify the compounds responsible for the synergisms observed.
- Hydrophilic and lipophilic compounds in Arenaria montana L. and Chenopodium ambrosioides L. and bioactivity of their infusions and methanolic extractsPublication . 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. Furthermore, the bioactive properties (antioxidant and antitumour activities, and hepatotoxicity) of their infusions and methanolic extracts were evaluated and compared. Radical scavenging activity, reducing power and inhibition of lipid peroxidation in brain homogenates were used to evaluate antioxidant activity, while antitumor potential was screened in different human tumour cell lines: MCF-7 (breast carcinoma), NCI-H460 (lung carcinoma), HCT-15 (colon carcinoma), HeLa (cervical carcinoma) and HepG2 (hepatocellular carcinoma). Hepatotoxicity in nontumour liver cells was also accessed using a primary culture established by us (PLP2). C. ambrosioides was the most active regarding antioxidant activity (EC50 values 0.47-2.53 and 0.25-2.32 mg/mL for methanolic extract and infusion, respectively). A. montana infusion showed the highest antitumour activity in all the tested cell lines (GI50 values 58.67-231.08 μg/mL). This plant also gave the highest levels of saturated (43.16%) and monounsaturated (10.16%) fatty acids and sugars (10.15 g/100 g dw), particularly fructose (5.46 g/100 g dw). C. ambrosioides showed the highest content of α-linolenic acid (48.54%), tocopherols (202.34 mg/100 g dw), particularly α-tocopherol (199.37 mg/100 g dw) and organic acids (7.58 g/100 g dw), mainly oxalic acid (5.64 g/100 g dw). Overall, the studied plants proved to be good sources of natural bioactive compounds which may have industrial uses.