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- Metabolomic approach to assess the effect of the foraging year on the anti-elastase activity of Cytinus hypocistis (L.) L.Publication . Silva, Ana Rita; Ayuso, Manuel; García, Pablo A.; Barros, Lillian; Edrada-Ebel, RuAngelieCytinus hypocistis (L.) L. is a wild edible parasitic plant on numerous members of the Cistaceae family. Although its bioactive properties were potentially attributed to its hydrolysable tannin content, its chemical composition is largely unknown, and the bioactive substances have not yet been identified [1,2]. Thus, this work aimed to investigate its potential to inhibit human elastase, an important anti-ageing mechanism. The plant material was collected in Castro Daire, Portugal, from the host species Halimium lasianthum (Lam.) Greuter on the same calendar date in June for three consecutive years (2018, 2019, and 2020). Metabolomic- based analytical techniques were applied to disclose the discriminating features of the anti-elastase activity of nine hydroethanolic extracts (three per year). The discriminating features among samples were identified using a multivariate PLS-DA of the LC-HRMS data. Dereplication of the discriminating metabolites obtained from the loadings plot revealed that year-one had the best inhibitory activity with IC50s of 13 to 22 μg/mL and were comprised of high molecular weight compounds ranging between 500 and 950 Da. However, the second-year collection exhibited a significant decrease in the biological activity of 120 to 128 μg/mL indicating the occurrence of low molecular weight compounds between 150 and 300 Da. Year three gave IC50s of 74 to 109 μg/mL. This study offers an evidential hypothesis on the effect of annual environmental changes on the chemical profile of a parasitic plant. Albeit, the relative abundance of the discriminating features was minimal, it was significant enough to affect the anti-elastase bioactivity of the extracts
- Exploring the bioactive potential of Artemisia annua L. hydroethanolic extracts obtained by microwave-assisted extractionPublication . Calhelha, Ricardo C.; Alves, Maria José; Barros, Lillian; Pinho, Simão; Ayuso, ManuelArtemisia annua L. is known for producing artemisinin, a sesquiterpene lactone compound, which is applied to treat of malaria [1]. Its pharmacodynamic and pharmacokinetic characteristics, as well as its strong capacity for Plasmodium elimination, have raised many expectations for this new class of antimalarial drugs [2]. However, this plant has been also used in traditional Chinese medicine to treat of various diseases since ancient times. Recent studies have focused on its extensive biological activities, which makes this plant an excellent candidate to be used in clinical therapies. Thus, this work aimed to evaluate different bioactivities from a hydroethanolic extract of Artemisia annua. The plant extract in ethanol:water (80:20 v/v) was obtained by microwave-assisted extraction. The antioxidant activity was determined by thiobarbituric acid reactive substances (TBARS) assay, showing a potent activity with an IC50 of 10.3 ± 1.0 μg/mL. A. annua L. extract also exhibited antibacterial and antifungal properties, with concentrations ranging from 2.5 to 10 mg/mL. The ethanolic extract was very effective against the four tumor cell lines, presenting GI50 ranging from 21 to 61 μg/mL and excellent anti-inflammatory activity (38 μg/mL). However, it was also cytotoxic against the two normal cells tested (50 and 19 μg/mL). Concluding, despite the excellent biological activities exhibited by A. annua L. extract, it was also demonstrated to be cytotoxic against normal cells. Therefore, further studies are necessary to study how the cytotoxicity of this extract could be reduced without affecting its bioactive properties.
- Otimização de processos de extração de antocianinas a partir de cálices de Hibiscus sabdariffa L. para produção de corantes alimentares naturaisPublication . Ayuso, Manuel; Pereira, Eliana; Pinela, José; Roriz, Custódio Lobo; Prieto Lage, Miguel A.; Barreiro, M.F.; Barros, Lillian; Ferreira, Isabel C.F.R.A seletividade do consumidor na escolha de produtos alimentares contendo aditivos tem desafiado a indústria alimentar e os centros de investigação a encontrar novas fontes e métodos de extração eficientes para a produção sustentável de ingredientes de base natural com capacidade corante [1]. Nesta vertente, as plantas surgem como uma fonte promissora de pigmentos naturais bioativos com potencial aplicação no setor industrial. Hibiscus sabdariffa L. é um bom exemplo, pois trata-se de uma espécie cujo cálice detém uma elevada concentração de antocianinas [2]. Visando maximizar a recuperação destes compostos antociânicos a partir do cálice desta espécie para posterior utilização como corantes alimentares, este estudo foi delineado com o objetivo de otimizar dois métodos de extração, assistidos por calor (HE) e ultrassons (UE), utilizando a metodologia de superfície de resposta (RSM). Para otimização, foi implementado um desenho compostos central de cinco níveis combinando três variáveis independentes, nomeadamente tempo (t), percentagem de etanol (S) e temperatura (T) ou potência (P) do ultrassons. Os teores das antocianinas delfinidina-3-O-sambubiósido e cianidina-3-O-sambubiósido foram quantificados por LC-DAD-ESI/MSn e usadas como critérios de resposta para otimização por RSM. Os modelos teóricos foram ajustados através de uma equação polinomial de segunda ordem e as respostas maximizadas pelo método Simplex [3]. Após otimizar as condições para as variáveis t, T e S ou P, procedeu-se à otimização da razão sólido/liquido (S/L) para HE e UE. Os modelos desenvolvidos foram ajustados com sucesso aos dados experimentais e utilizados para determinar as condições ideais de extração. A UE foi mais eficiente, permitindo recuperar 23,83 mg de antocianinas por cada g de material vegetal seco e obter 51,76 mg desses pigmentos por cada g de extrato ao aplicar as condições de processamento ótimas: t = 26,1 min, P = 296,6 W e S = 39,1% etanol. A quantidade de antocianinas obtida através da extração UE foi cerca de 3 vezes superior à quantidade obtida por HE. Quanto à razão S/L, o incremento desta quarta variável aumentou os rendimentos de extração de antocianinas, atingindo um máximo ao utilizar 200 g/L [3]. Os resultados demonstram que H. sabdariffa é uma fonte de antocianinas viável para produzir corantes de base natural, através de uma metodologia economicamente exequível à escala industrial.
- Comparative analysis of the chemical composition of different portuguese breadPublication . Pascoalino, Liege; Ayuso, Manuel; Pereira, Eliana; Ferreira, Elisabete; Ferreira, Isabel C.F.R.; Barros, LillianBakery products are one of the most widely consumed foods in the world. Among them, bread is daily consumed by all social classes due to its macro (carbohydrates, protein, and fat) and micronutrients (minerals and vitamins). However, the refined wheat used in traditional baking diminishes its nutritional quality by reducing its dietary fibre, vitamins, minerals, and phytochemicals1. In addition, studies have been showing some health-related problems associated with obesity and diabetes. Compared with others made with different cereals or whole grains, traditional bread tends to be less satiating and increase the postprandial glycaemic index2. Thus, the great challenge of the cereal industry today is to innovate and reinvent a large part of its products, mainly by changing the traditional composition of food products, since it seems to be an effective method to improve the diet. Alternatives such as whole grains, other cereals or the incorporation of protein-rich flours such as legumes may help improve the nutritional quality of bread and have a favourable impact on consumers’ health3. Thus, in this study, a comparative analysis, and chemical parameters among two traditional wheat bread (smoked sausage and cheese, SSCB; and wine, WB) and five non-conventional bread supplemented with different cereals (rye, RB; legumes and cereals, LCB; biological seed, BSeB; biological spelt, BSpB; and chickpea and sprouted seeds, CSSB) was performed. The bread centesimal composition was evaluated by AOAC official procedures; free sugars using HPLC-RI, and fatty acids by GC-FID. Regarding the chemical characterisation of traditional bread, SSCB showed a high protein concentration (9.95±0.02 g 100g-1 FW). However, it was also the bread with the highest amount of fat and a high percentage of saturated fatty acids (6.1±0.1 g 100g-1 FW and 67.1±0.4 %, respectively). WB revealed the highest concentration of free sugars (37.6±1.8 g 100g-1 FW). In general, the non-conventional bread presented lower energy and higher polyunsaturated fatty acids than the traditional. Additionally, RB, BSpB, and CSSB presented the lowest fat concentration, with CSSB showing the highest concentration of dietary fibre (7.2±0.4 g 100g-1 FW). This study demonstrates that incorporating alternative flours produces bread of higher nutritional quality. In general, non-conventional bread is lower in calories, fat and have a higher percentage of polyunsaturated fatty acids and dietary fibre.
- Extrato de Gomphrena globosa L. como corante natural em biscoitos: efeito em diferentes parâmetros físicosPublication . Ayuso, Manuel; Roriz, Custódio Lobo; Pereira, Eliana; Heleno, Sandrina A.; Carocho, Márcio; Morales, Patricia; Barros, Lillian; Ferreira, Isabel C.F.R.Nos últimos anos, consumidores e indústria têm procurado corantes naturais que sejam seguros e, simultaneamente, associados a efeitos benéficos para a saúde. Existem alguns corantes naturais autorizados pela EFSA, no entanto, não conseguem satisfazer todas as necessidades da indústria pela sua instabilidade, nomeadamente a alterações de temperatura, pH, luminosidade entre outros fatores [1]. Assim, a comunidade científica tem-se debruçado no estudo de matrizes naturais para obtenção de agentes com diferentes funções, nomeadamente função corante [2]. Entre as moléculas naturais com capacidade corante encontram-se as betacianinas, compostos pigmentados, com elevado poder corante, obtidas preferencialmente a partir de beterraba (tonalidades na gama dos vermelhos). Neste sentido, o presente trabalho visa a utilização de flores de Gomphrena globosa L. (perpétua roxa), como fonte de betacianinas para potencial aplicação na indústria alimentar [3]. As flores de G. globosa foram sujeitas a uma extração assistida por ultrassons previamente otimizada (t = 22 min, P = 300 W, Et = 0% e S/L = 5 g/L), obtendo-se 47 ± 5 mg gonfrenina/g de extrato. Os extratos obtidos foram liofilizados e incorporados em biscoitos para avaliação das suas características físicas nomeadamente: a) cor, com recurso a um colorímetro para análise das coordenadas L* = Luminosidade, a* = vermelho/verde e b* = amarelo/azul; b) textura, através de um texturómetro, analisando os parâmetros de dureza, adesividade, elasticidade, coesão, mastigabilidade e resiliência. Estes parâmetros foram analisados ao longo de um tempo de prateleira de 30 dias e comparados com: i) biscoitos sem corante, ii) biscoitos com extrato corante liofilizado; iii) biscoitos com extrato de corante comercial (E162). De acordo com os resultados obtidos nos parâmetros de avaliação de cor, verificou-se que o extrato de G. globosa liofilizado apresentou resultados mais promissores em termos de estabilidade (L *56; a *25.5; b *4.3), mantendo uma coloração rosa após a cozedura e durante os 30 dias de análise, enquanto que, o corante comercial E162 (L *60.7; a *23,2; b *18,1) sofreu alterações na capacidade corante, provocadas pela cozedura, no entanto, apresentou também grande estabilidade ao longo dos 30 dias de análise. Nos parâmetros de textura avaliados, as mudanças gerais na textura foram resultado de uma interação significativa entre o tipo de corante e a passagem do tempo. A dureza dos biscoitos diminuiu devido à retrogradação, enquanto os parâmetros de adesividade, elasticidade, coesão e resiliência aumentaram, mas não de uma forma significativa. Desta forma, com o decorrer deste trabalho foi possível concluir que o extrato obtido a partir de flores de G. globosa, é uma fonte de betacianinas com potencial para aplicação na indústria alimentar como corante natural. De realçar que este extrato apresenta uma tonalidade rosa diferente do corante comercial (avermelhado), pelo que pode ser considerado como possível candidato corante de tonalidade rosa para a indústria alimentar. Estão em curso mais estudos de estabilidade, de forma a garantir as melhores condições de armazenamento e aplicação deste extrato.
- Fig “Ficus carica L.” and its by-products: A decade evidence of their health-promoting benefits towards the development of novel food formulationsPublication . Ayuso, Manuel; Carpena Rodríguez, María; Taofiq, Oludemi; Albuquerque, Tânia Gonçalves; Simal-Gandara, Jesus; Oliveira, Beatriz; Prieto Lage, Miguel A.; Ferreira, Isabel C.F.R.; Barros, LillianThe food industry constantly searches for natural derived bioactive molecules with preventive and therapeutic effects using innovative and sustainable strategies. Fig production and processing generate a considerable amount of by-products (leaves, pulp, peels, seeds, and latex) with limited commercial exploitation and negative impact on the environment. These by-products are important sources of high value-added in- gredients, including anthocyanins and pectins that can be of particular interest to the food industry as functional colourants, emulsifiers, and additives. Scope and approach: This review curates recent advances in the valorisation of fig by-products as valuable sources of bioactive molecules for functional food development. Special attention was given to widely used extraction processes, main bioactive compounds, relevant biological properties, and the application of recovered bioactives for functional food development. Key findings and conclusions: Fig by-products are essential sources of structurally diverse bioactive molecules with unique antidiabetic, anti-inflammatory, anti-tumour, immunomodulatory and cardioprotective properties. Owing to these health-promoting potentials, an integral valorisation approach involving sustainable technologies to recover these high value-added ingredients and its utilisation in novel food formulation development should be further stimulated.
- Valorisation of a threatened plant species through in vitro culture elicitation of phenolic compoundsPublication . Ayuso, Manuel; Dias, Maria Inês; Pinela, José; Gallego, Pedro Pablo; Barreal, M. Esther; Barros, Lillian; Ferreira, Isabel C.F.R.Abstract: Ex situ conservation strategies, such as in vitro culture, have been suggested for the recovery of threatened plants close to extinction. In vitro culture or micropropagation is a plant-multiplication technique that allows to obtain a large number of clones in a short period of time and limited space, which can be used in reintroduction programs and for research purposes (1). This biotechnological tool also allows increasing the production yield of secondary metabolites, such as phenolic compounds, thus emerging as an efficient system to obtain high added-value bioactive compounds (2). This approach allows valorising the culture of threatened plants for their commercial use in different industrial sectors interested in bioactive compounds, such as the food and pharmaceutical industries. Therefore, the aim of this research was to study the phenolic compounds elicitation by cytokinins in roots and aerial parts of the in vitro cultured endangered plant Eryngium viviparum J. Gay (Fam. Apiaceae). E. viviparum explants were cultured in vitro in a solidified MS medium. A 3-level factorial design was implemented to study the effect of two cytokinins, 6-benzylaminopurin (BAP) and kinetin (KIN), at 0, 1 and 2 mg L-1, on the elicitation of phenolic compounds. The obtained plant material was lyophilized, reduced to powder, and submitted to a solid-liquid extraction with ethanol:water (80:20, v/v) to obtain combined extracts (3). Then, phenolic compounds were identified and quantified by HPLC-DAD-ESI/MS (3) and the main phenolic compounds with known bioactivities were correlated with both cytokinins. Seventeen phenolic compounds were identified in all E. viviparum hydroethanolic extracts, corresponding to 12 phenolic acids and 5 flavonoids. Rosmarinic and chlorogenic acids were the main bioactive phenolic acids. Regarding flavonoids, tectorigenin-O-glucuronide was identified and quantified only in the aerial parts. In the roots, the increase of phenolic acids was correlated with the presence of KIN in the culture media. Concerning the aerial parts, cytokinins did not correlate with phenolic acids, but KIN correlated with the increase of tectorigenin-O-glucuronide. In addition, the roots had a higher phenolic composition content than the aerial parts and the combination of both cytokinins promoted a doubling of the phenolic compounds concentration in some samples. Therefore, this study demonstrated the efficacy of in vitro culture in adding value to the threatened plant species E. viviparum, as the levels of valuable secondary metabolites were increased by elicitation, thus being a sustainable approach that can help save and valorise other endangered plants.
- Response surface methodology and artificial neural network modeling as predictive tools for phenolic compounds recovery from olive pomacePublication . Silva, Ana Rita; Ayuso, Manuel; Oludemi, Taofiq; Gonçalves, Alexandre; Melgar Castañeda, Bruno; Barros, LillianThis study optimized the extraction of three major phenolic compounds (oleuropein, tyrosol, and verbascoside) from olive pomace using microwave- and ultrasonic-assisted methods. Screening factorial design (SFD) and central composite design (CCD) were employed, and response surface methodology (RSM) and artificial neural networks (ANN) were used for data modeling. The microwave-assisted method in the SFD yielded higher compound amounts, with verbascoside showing a four-fold increase compared to the ultrasonic-assisted method. Factors like vessel diameter, ultrasonic power using UAE, and solvent acidity in both techniques had minimally impacted extractability. CCD-RSM revealed temperaturés significantly affect on oleuropein, but improved tyrosol recovery, with the effect on verbascoside being influenced by the temperature range. RSM and ANN integration enhanced understanding and prediction of factor behavior. Microwave-assisted extraction at 113 ◦C for 26 min, with minimum ramp time of 7.7 min, yielded 67.4, 57, and 5.1 mg of oleuropein, tyrosol, and verbascoside per gram of extract, respectively, with a prediction error ranging from 0.83 to 15.19.
- Bread freezing as a new alternative to consumptionPublication . Pascoalino, Liege; Ayuso, Manuel; Pereira, Eliana; Ferreira, Elisabete; Ferreira, Isabel C.F.R.; Barros, LillianThe growing consumer interest in health and food safety, as well as the increased consumption of fresh food, make frozen bread an increasingly popular alternative. This type of bread has several advantages, such as, large-scale manufacturing, economize manpower and equipment, and lowering production costs. Furthermore, one of the ways to extend shelf-life of ready-to-eat bread is to use deep freezing systems [1– 3]. In the present study, the effect of frozen storage time on the bread quality made from frozen dough, were studied, through the nutritional and chemical composition evaluation. Six equal multicereal breads were frozen, submitted to different storage times under deep freezing (190, 225, 251, 310, 344 and 694 days), and compared to the fresh multicereal bread. The nutritional profile was evaluated through the protein, ash, fat, and carbohydrate content, using official analysis methodologies (AOAC) and the energetic value was also estimated. The chemical composition regarding sugars and fatty were determined by chromatographic techniques, using a HPLC- RI and a GC-FID, respectively. In general, the results revealed that moister content is similar in all frozen breads, with values around 40%, while the fresh bread showed a content of 43.4%. The ash content presented values ranging between 1.51 ± 0.02 and 1.02 ± 0.02 g/100 g fresh weight (fw); and the mean value of the protein content in the samples was approximately 7 g/100 g fw. On the other hand, fiber showed values of 4% of total dietary fiber (TDF) fw for breads with longer frozen time, while the bread frozen for less time (190 days) and fresh bread showed values around 6% TDF fw. The fat content was also variable between fresh and frozen breads, however, the presence of polyunsaturated fatty acids (PUFA) in all samples was predominant, namely linoleic acid (C18:2n6c). Regarding the sugars profile, fructose, glucose, and maltose were detected in all bread samples, showing a total sugar value between 1.78 and 2.97 g/100g fw; and as expected, the most abundant sugar was maltose, a common sugar found in cereal. Regarding the carbohydrate evaluation, the obtained results ranged between 40.4 and 43 g/100g fw for frozen breads and 38.3 g/100 g fw for fresh bread; and the energetic value presented values greater than 220 kcal/100g in all samples. The results obtained show that freezing may be a promising alternative for bread conservation, contributing to the reduction of the high percentage of disposal that happens in all industrialized countries.
- Non-alkaloid nitrogen containing compoundsPublication . Pereira, Eliana; Fernandes, Filipa Alexandra; Mandim, Filipa; Ayuso, Manuel; Ferreira, Isabel C.F.R.; Caleja, Cristina; Barros, LillianPlants have been the target of a growing interest by the scientific community in chemical and nutritional characterization studies, due to the presence of bioactive compounds and their potential industrial use, namely in food and pharmaceutical sectors. Different secondary metabolites found in plants ensure their survival and reproduction. Non-alkaloids compounds are an important group of secondary metabolites present in the plant kingdom, which have been widely studied and aimed at their industrial application, namely in the pharmaceutical area. This group of compounds has an important ecological function of protection; and in addiction an excellent bioactive performance has been highlighted and exploited for promising application in the pharmaceutical industry. This chapter focuses on the characterization of different classes of non-alkaloid nitrogen compounds: non-protein amino acids, cyanogenic glycosides compounds, and glucosinolates. Its chemical and structural characteristics as well as its biosynthesis and presence in plants will be presented. The bioactivities presented by each of the classes will be equally focused as well as their applicability.