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- Lentil flour formulations to develop new snack-type products by extrusion processing: phytochemicals and antioxidant capacityPublication . Morales, Patricia; Cebadera-Miranda, Laura; Cámara Hurtado, Montaña; Reis, Filipa S.; Barros, Lillian; Berrios, José de J.; Ferreira, Isabel C.F.R.; Cebadera-Miranda, LauraExtrusion process has been generally applied to the production of cereal-based snacks. However, in recent years, extrusion process has been also used for the development of pulses-based snacks, with few studies focussing on the incorporation of these food ingredients to obtain bioactive compounds enriched snacks with acceptable quality. The effects of the extrusion processing on fiber (soluble and insoluble), total available carbohydrates, tocopherols, organic acids, total phenolics, hydroxycinnamic acids, hydroxybenzoic acids and flavonols, as well as on the antioxidant capacity of different lentil-based, fiber-enriched flours were evaluated. Total dietary fiber (TDF) in the extruded flours ranged between 7.49 and 10.22 g/100 g, with a decrease from 6 to 37% which correlated with a significant increase in the fiber soluble fraction. α-, γ- and δ-Tocopherols were characterized in all the analyzed samples, being γ-tocopherol the major isoform, before and after extrusion. Additionally, a marked decrease of 83 to 94% in total tocopherol content after extrusion processing was observed and the decrease was more significant on quinic acid content. Conversely, an increase in most polyphenolic fractions was observed, probably due to the effect of extrusion process to induce hydrolysis of polyphenols bound fiber and/or proteins moieties, changing from non-extractable to extractable polyphenols. Similar increase in antioxidant activity was also observed in most formulated lentil-based flours, measured by four different antioxidant assays. Only flavonols presented an extensive content decrease of about 62 to 82%, after extrusion treatment.
- Bioactive molecules profile of two Lactarius species from SerbiaPublication . Reis, Filipa S.; Stojković, Dejan; Soković, Marina; Ćirić, Ana; Glamočlija, Jasmina; Barros, Lillian; Ferreira, Isabel C.F.R.Mushrooms have become attractive as functional foods and as a source of many biologically active compounds. Different wild mushroom species were reported to have an excellent nutritional value and bioactivity that includes antioxidant and antitumor properties [1-3]. Hence, in recent times, the consumption of mushrooms has risen greatly, comprising a large number of species. This work presents the profile of organic acids, tocopherols and phenolic compounds of two species of wild mushrooms from Serbia: Lactarius piperatus and Lactarius rufus. Organic acids were determined by UFLCPDA; tocopherols were analysed by HPLC-fluorescence and the phenolic compounds characterization was made by HPLC-DAD/MS. It was possible to quantify oxalic, quinic, malic, citric and fumaric acids in both species, being malic acid the majority organic acid found in these samples. However, L. rufus revealed a higher content in total organic acids comparing with L. piperatus (12.43 g/100 g dw and 9.40 g/100 g dw, respectively). Concerning tocopherols, the four isoforms of vitamin E (α-, β-, γ- and δ-tocopherol) were detected in both species. Herein, L. piperatus was the species that holds the highest concentration of tocopherols (80.38 μg/100 g dw), due to the contribution of β-tocopherol (47.43 μg/100 g dw). About phenolic compounds, it was only possible to quantify p-hidroxibenzoic acid in L. rufus. Nevertheless, it was detected the related compound cinnamic acid in both species. This work results from a Project in cooperation with the University of Belgrade, and the main purpose is the enhancement of the mycological flora as functional food and as a source of compounds of interest, allowing comparison between Portuguese and Serbian species.
- Chemical composition and nutritional value of the most widely appreciated cultivated mushrooms: an inter-species comparative studyPublication . Reis, Filipa S.; Barros, Lillian; Martins, Anabela; Ferreira, Isabel C.F.R.Herein, it was reported and compared the chemical composition and nutritional value of the most consumed species as fresh cultivated mushrooms: Agaricus bisporus (White and Brown mushrooms), Pleurotus ostreatus (Oyster mushroom), Pleurotus eryngii (King oyster mushroom), Lentinula edodes (Shiitake) and Flammulina velutipes (Golden needle mushroom). Shiitake revealed the highest levels of macronutrients, unless proteins, as also the highest sugars, tocopherols and PUFA levels, and the lowest SFA content. White and brown mushrooms showed similar macronutrients composition, as also similar values of total sugars, MUFA, PUFA and total tocopherols. Oyster and king oyster mushrooms gave the highest MUFA contents with similar contents in PUFA, MUFA and SFA in both samples. They also revealed similar moisture, ash, carbohydrates and energy values. This study contributes to the elaboration of nutritional databases of the most consumed fungi species worldwide, allowing comparison between them. Moreover it was reported that cultivated and the wild samples of the same species have different chemical composition, including sugars, fatty acids and tocopherols profiles.
- Biomolecule profiles in inedible wild mushrooms with antioxidant valuePublication . Reis, Filipa S.; Pereira, Eliana; Barros, Lillian; Sousa, Maria João; Martins, Anabela; Ferreira, Isabel C.F.R.The use of natural products isolated from mushrooms, included inedible species, against infection, cancer diseases and other oxidative-stress related diseases is one of the cornerstones of modern medicine. In the present work, the antioxidant molecule profiles of inedible mushroom species were evaluated and compared with those of edible species. The order of antioxidant abundance found in inedible wild mushrooms was: phenolics > flavonoids > ascorbic acid > tocopherols > carotenoids, similar to that of edible species. Furthermore the same energetic biomolecules were found including the disaccharide trehalose, the monosaccharide alcohol derivative mannitol and the fatty acids palmitic, oleic and linoleic acids. Fomitopsis pinicola revealed a very high phenolics concentration (388 mg GAE/g extract) and powerful antioxidant properties, mainly reducing power (EC50 value 60 g/mL similar to the standard Trolox®). It could find applications in the prevention of free radical-related diseases as a source of bioactive compounds.
- Chromatographic techniques to obtain the biomolecules profile of wild Suillus granulatesPublication . Reis, Filipa S.; Barros, Lillian; Martins, Anabela; Vasconcelos, M. Helena; Morales, Patricia; Ferreira, Isabel C.F.R.In recent years the interest in naturally occurring compounds has been increasing worldwide. Indeed, many of the bioactive compounds currently used as medicines have been synthesized based on the structure of natural compounds [1]. In order to obtain bioactive fractions and subsequently isolated compounds derived from natural matrices, several procedures have been carried out. One of these is to separate and assess the concentration of the active compound(s) present in the samples, a step in which the chromatographic techniques stand out [2]. In the present work the mushroom Sui/Ius granulatus (L.) Roussel was chemically characterized by chromatographic techniques coupled to different detectors, in order to evaluate the presence of nutritional and/or bioactive molecules. Some hydrophilic compounds, namely free sugars, were identified by high performance liquid chromatography coupled to a refraction index detector (HPLC-RI), and organic and phenolic acids were assessed by HPLC coupled to a photodiode array detector (HPLC-PDA). Regarding lipophilic compounds, fatty acids weredetermined by gas chromatography with a flame ionization detector (GC-FID) and tocopherols by HPLC-fluorescence detection. Mannitol and trehalose were the main free sugars detected. Different organic acids were also identified (i.e. oxalic, quinic and fumaric acids), as well as phenolic acids (i.e. gallic and p-hydroxybenzoic acids) and the related compound cinnamic acid. Mono- and polyunsaturated fatty acids were the prevailing fatty acids and a-, ~- and ~-tocopherol were the isoforms of vitamin E detected in the samples. Since this species proved to be a source of biologically active compounds, the antioxidant and antimicrobial properties were evaluated. The antioxidant activity was measured through the reducing power, free radical's scavenging activity and lipid peroxidation inhibition of its methanolic extract, and the antimicrobial activity was also tested in Gram positive and Gram negative bacteria and iri different fungi. S. granulatus presented antioxidant properties in all the performed assays, and proved to inhibit the growth of different bacterial and fungal strains. This study is a first step for classifying S. granulatus as a functional food, highlighting the potential of mushrooms as a source of nutraceutical and biologically active compounds.
- A irradiação como tecnologia pós-colheita viável para conservação de cogumelos, vegetais e plantas aromáticasPublication . Pinela, José; Reis, Filipa S.; Pereira, Eliana; Fernandes, Ângela; Oliveira, Beatriz; Antonio, Amilcar L.; Cabo Verde, Sandra; Ferreira, Isabel C.F.R.A irradiação é um tratamento pós-colheita utilizado para processar produtos destinados à indústria alimentar e farmacêutica. Esta tecnologia é frequentemente combinada com outros processos de conservação, tais como a secagem e o embalamento, para tirar partido de possíveis efeitos sinérgicos. De facto, a elevada perecibilidade de alguns alimentos e matérias-primas torna imprescindível aplicar tratamentos de conservação capazes de aumentar o tempo de vida útil, mas com um impacto mínimo em atributos de qualidade. Este estudo pretendeu avaliar a adequabilidade da irradiação para conservar parâmetros nutricionais de cogumelos, vegetais e plantas aromáticas durante o tempo de vida útil. O cogumelo e as plantas aromáticas foram irradiados com feixe de eletrões a uma dose máxima 10 kGy e analisadas após irradiação e passados 6 e 12 meses ou 12 e 18 meses, respetivamente. Os vegetais frescos foram irradiados numa câmara experimental de 60Co a uma dose máxima de 6 kGy. Estes foram analisados antes de irradiar e após 7 ou 14 dias de armazenamento a 4 °C. O tratamento de irradiação permitiu manter mais eficazmente o perfil nutricional do cogumelos e dos vegetais durante o armazenamento, comparativamente com amostras não irradiadas. Além disso, o tempo de armazenamento teve um maior impacto no perfil nutricional do cogumelo do que a irradiação (com exceção dos ácidos gordos). No caso das plantas aromáticas, apesar de a irradiação ter atenuado perdas de qualidade durante o armazenamento, não foi possível identificar uma tendência geral pois os fatores testados tiveram efeitos dissimilares nas diferentes espécies.
- A study on the medicinal mushroom Cordyceps militaris (L.) link: chemical characterization, antioxidant, antimicrobial and antiproliferative propertiesPublication . Reis, Filipa S.; Stojković, Dejan; Glamočlija, Jasmina; Ćirić, Ana; Van Griensven, Leo J.L.D.; Soković, Marina; Ferreira, Isabel C.F.R.The Cordyceps genus is well known for its medicinal properties. A number of bioactive constituents from Cordyceps species have been reported such as antibacterial, antifungal, immunopotentiating or antitumor agents [1]. The anti-inflammatory and anti-angiogenic properties of Cordyceps militaris (L.) Link have been reported as also the antioxidant activity of its cultured mycelium [2]. In this work, the chemical characterization of C. militaris was performed, includingbioactive compounds (free sugars, unsaturated fatty acids, tocopherols, organic acidsand phenolic compounds). The antioxidant potential of its methanolic extract was evaluated (reducing power, scavenging activity and lipid peroxidationinhibition) as also the antimicrobial activity (tested towards Gram positive and Gram negative bacteria and eight microfungi) and antiproliferative properties (tested in different human tumor cell lines). Mannitol and trehalose were the main free sugars found in this species (2.01 and 24.71 g/100 g dw, respectively). The fatty acid quantified in higher amounts was linoleic acid (68.00% of total fatty acids). a-Tocopherol was the only isoform of vitam in E detected (55.86 j.lg/1 00 g dw). The organic acids found in this mushroom were oxalic (0.33 g/1 00 g dw), citric (7.97 g/1 00 g dw) and fumaric (0 .1 3 g/100 g dw) acids. p-Hydroxybenzoic acid was the only phenolic acid quantified in C. militaris (0.02 mg/1 00 g dw), but cinnamic acid was also found (0. 11 mg/1 00 g dw). The lowest EC50 values for the antioxidant potential were presented in lipid peroxidation inhibition assays, namely in 13-carotene/l inoleate and TBARS assays (1.05 mg/ml and 0. 77 mg/ml, respectively). The methanolic extract also revealed strong antibacterial and antifungal activities, and it was able to inhibit the proliferation of MCF-7 (breast}, NCI-H460 (non-smalllung),HCT-15 (colon) and Hela (cervical) human carcinoma cell lines.
- Chemical characterization and biological activities of two varieties of xoconostle fruits: Opuntia joconostle F.A.C. Weber ex Diguet and Opuntia matudae ScheinvarPublication . Garcia-Saavedra, Natalia Moraleja; Barros, Lillian; Reis, Filipa S.; Roriz, Custódio Lobo; Alves, Maria José; García-Hernandez, Mariel; Pérez-Rodríguez, María Luisa; Sánchez-Mata, María Cortes; Ramírez-Moreno, Esther; Ferreira, Isabel C.F.R.The present work focusses on the chemical characterization and bioactive properties of Opuntia joconostle F.A.C. Weber ex Diguet and Opuntia matudae Scheinvar fruits. This research showed that xoconostle cv. Cuaresmeño (O. joconostle) and xoconostle cv. Rosa (O. matudae) are a good source of PUFAs and tocopherols. Moreover, both fruits revealed the presence of ten phenolic compounds (e.g., ferulic acid hexoside, quercetin-O-di-deoxyhexosyl-hexoside, and kaempferol-O-(di-deoxyhexosyl)-hexoside), as well as other organic acids (oxalic, malic, ascorbic and citric acids), and two betacyanins (betanin and isobetain). The hydroethanolic extracts of both fruits exhibited antioxidant activity, and inhibited the growth of several bacteria strains and of the yeast Candida albicans. As expected, xoconostle cv. Cuaresmeño was the fruit with highest antioxidant potential, since it was also the one that showed the highest content of bioactive compounds, with the exception of betacyanins. Overall, both fruits are revealed to be a good source of nutritive and bioactive compounds.
- Dragon fruits as an alternative source of colorants: evaluation of antibacterial activity and colouring capacityPublication . Roriz, Custódio Lobo; Dias, Maria Inês; Reis, Filipa S.; Pires, Tânia C.S.; Alves, Maria José; Fernandes, Filipa A.; Morales, Patricia; Barros, Lillian; Ferreira, Isabel C.F.R.Betalains are a group of secondary metabolites named chromoalkaloids that are synthesized from tyrosine. These compounds have gained some attention in the last few years mainly due to their interesting bioactive potential, namely antioxidant, antimicrobial, and other bioactive properties [1]. Their strong and vibrant colours are also one of the characteristics by which these compounds have gained visibility in the food and pharmaceutical industries [2]. Betalains can be divided in two groups regarding the colour range: betaxanthins in the orange to yellow range, and betacyanins in the purple to pink range. Thereby, these compounds can be used as natural colouring agents, providing alternatives to the massively used artificial counterparts [3]. Although there are already some natural options in the market, these are not enough to meet the needs of the food industry, due to the growing concern of consumers regarding what they eat. Thus, the objectives of this work were to: i) obtain bioactive extracts and with strong colouring capacity from the epicarp of two pitaya varieties, white-fleshed pitaya Hylocereus undatus (Haworth) Britton & Rose (WFP) and red-fleshed pitaya Hylocereus costaricensis (F.A.C.Weber) Britton & Rose (RFP); ii) chemically characterize the betalains’ content through HPLC-DAD-ESI/MS; iii) evaluate the bioactive properties of the extracts, namely antimicrobial activity. The extracts were obtained through a dynamic maceration assisted by heat, and the betacyanins’ profile was characterized by HPLC-DAD-ESI/MS. The antibacterial capacity was determined against a panel of Gram-negative and Gram-positive bacteria using the colorimetric method of rapid detection with p-iodonitrotetrazolium chloride (INT), and the responses obtained were expressed as minimum inhibitory (MIC) and minimum bactericidal (MBC) concentrations. By the chromatographic analysis of the extracts it was possible to identify six compounds in both samples. For the WFP the major compounds identified were 6'-O-malonylbetanin (phylocactin), followed by 4'-malonyl-betanin, while for the RFP the major compound found was phylocactin. In the evaluation of the antibacterial activity, both extracts showed MIC and MBC values that ranged from 10 to 20 mg/mL. Gram-positive bacteria showed to be more susceptible to both extracts then the negative strains. Further studies need to be conducted to better understand the correlation between the bioactive potential and the betacyanins’ composition. Nevertheless, these natural matrixes proved to be viable alternatives for obtaining colouring extracts with antimicrobial properties.
- The methanolic extract of Cordyceps militaris (L.) Link fruiting body shows antioxidant, antibacterial, antifungal and anti human tumor cell lines propertiesPublication . Reis, Filipa S.; Barros, Lillian; Calhelha, Ricardo C.; Ćirić, Ana; Van Griensven, Leo J.L.D.; Soković, Marina; Ferreira, Isabel C.F.R.Being Cordyceps militaris (L.) Link recognized as a medicinal and edible mushroom, this work intends to reveal new interesting bioactive molecules that could be isolated from this species. Hydrophilic and lipophilic compounds were analysed by chromatographic techniques coupled to different detectors. The methanolic extract of C. militaris was tested for its antioxidant, antibacterial, antifungal and anti-proliferative properties in different human tumor cell lines. Mannitol (2.01 g/100 g dw) and trehalose (24.71 g/100 g) were the free sugars found in C. militaris. Polyunsaturated fatty acids (68.87%) predominated over saturated fatty acids (23.40%) and δ-tocopherol was the only isoform of vitamin E detected (55.86 μg/100 g). The organic acids found in this mushroom were oxalic, citric and fumaric acids (0.33, 7.97 and 0.13 g/100g, respectively). p-Hydroxybenzoic acid was the only phenolic acid quantified in this species (0.02 mg/100 g); although cinnamic acid was also found (0.11 mg/100 g). The methanolic extract of C. militaris proved to inhibit lipid peroxidation, have reducing power and scavenge free radicals. This extract also revealed strong antibacterial and antifungal properties. Finally, the C. militaris extract was able to inhibit the proliferation of MCF-7 (breast), NCI-H460 (non-small lung), HCT-15 (colon) and HeLa (cervical) human carcinoma cell lines.