Percorrer por autor "Caleja, Cristina"
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- Agrocybe cylindracea bio-residues: a sustainable source of ergosterol-rich bioactive extractsPublication . Silva, Ana Rita; Pinela, José; Caleja, Cristina; Costa, Cristina; Barros, Joana; Ferreira, Inês; Nunes, João; Prieto Lage, Miguel A.; Barros, Lillian; Ferreira, Isabel C.F.R.The world production of edible mushrooms has increased more than 30‐fold since 1978 and, on average, each customer consumes 5 kg of mushrooms per year [1]. Depending on the dimension of the mushroom industry, the amount of obtained by-products may range from 20 to 35% in weight of fresh mushroom [2]. Indeed, 38% of the 90 million tonnes of food waste produced by the European Union every year has its origin in the food manufacturing sector [3]. However, there are several strategies of transforming these wastes into high value-added products based on the cascade use principle, and this is exactly what the MicoBioExtract project aims to perform. Thus, the bio-residues of a popular edible mushroom in southern Europe, Agrocybe cylindracea, were studied as a sustainable source of bioactive extracts [4]. Ergosterol has been reported to be one of the most important compounds, contributing to the health-promoting benefits, associated with mushrooms’ consumption [2]. Its extraction was performed using a heat-assisted technique and applying the response surface methodology, in order to optimize the combined effects of the variables time, temperature and solvent percentage, using a circumscribed central composite design with 16 independent combinations and 4 replicated centre points. At the optimum condition predicted by the model, the bioactivity of the extract was tested, evaluating the antioxidant (TBARS assay) and cytotoxic (in a porcine liver primary cell culture, PLP2) activities. The results obtained from the optimization study showed a significant interaction between temperature and extraction time, with an 8.24% extraction yield. The global optimum condition for ergosterol extraction predicted by the model was 150 min at 90 °C, with 329 mg of ergosterol per 100 g of dry weight sample. Regarding the bioactive potential, namely the antioxidant activity, this extract was capable of preventing the formation of malondialdehyde, a secondary product of lipid peroxidation in the TBARS assay. Concerning the cytotoxicity of the extracts against the PLP2 cell line, the results showed no significant cytotoxic effect, with GI50 values higher than 400 μg/mL. Thus, the extraction of molecules with a high nutritional and bioactive value from mushroom bio-residues and the goal to incorporate them in functional foods and nutraceuticals could boost the circular bio-economy, and help developing strategies towards promoting sustainability.
- Agrocybe cylindracea bio-residues: a sustainable source of ergosterol-rich bioactive extractsPublication . Silva, Ana Rita; Pinela, José; Caleja, Cristina; Costa, Cristina; Barros, Joana; Ferreira, Inês; Nunes, João; Prieto Lage, Miguel A.; Barros, Lillian; Ferreira, Isabel C.F.R.The world production of edible mushrooms has increased more than 30‐fold since 1978 and, on average, each customer consumes 5 kg of mushrooms per year [1]. Depending on the dimension of the mushroom industry, the amount of obtained by-products may range from 20 to 35% in weight of fresh mushroom [2]. Indeed, 38% of the 90 million tonnes of food waste produced by the European Union every year has its origin in the food manufacturing sector [3]. However, there are several strategies of transforming these wastes into high value-added products based on the cascade use principle, and this is exactly what the MicoBioExtract project aims to perform. Thus, the bio-residues of a popular edible mushroom in southern Europe, Agrocybe cylindracea, were studied as a sustainable source of bioactive extracts [4]. Ergosterol has been reported to be one of the most important compounds, contributing to the health-promoting benefits, associated with mushrooms’ consumption [2]. Its extraction was performed using a heat-assisted technique and applying the response surface methodology, in order to optimize the combined effects of the variables time, temperature and solvent percentage, using a circumscribed central composite design with 16 independent combinations and 4 replicated centre points. At the optimum condition predicted by the model, the bioactivity of the extract was tested, evaluating the antioxidant (TBARS assay) and cytotoxic (in a porcine liver primary cell culture, PLP2) activities. The results obtained from the optimization study showed a significant interaction between temperature and extraction time, with an 8.24% extraction yield. The global optimum condition for ergosterol extraction predicted by the model was 150 min at 90 °C, with 329 mg of ergosterol per 100 g of dry weight sample. Regarding the bioactive potential, namely the antioxidant activity, this extract was capable of preventing the formation of malondialdehyde, a secondary product of lipid peroxidation in the TBARS assay. Concerning the cytotoxicity of the extracts against the PLP2 cell line, the results showed no significant cytotoxic effect, with GI50 values higher than 400 μg/mL. Thus, the extraction of molecules with a high nutritional and bioactive value from mushroom bio-residues and the goal to incorporate them in functional foods and nutraceuticals could boost the circular bio-economy, and help developing strategies towards promoting sustainability.
- Análise cromatográfica de um extrato fenólico de funcho utilizado no desenvolvimento de requeijões com propriedades funcionaisPublication . Caleja, Cristina; Barros, Lillian; Antonio, Amilcar L.; Ćirić, Ana; Soković, Marina; Oliveira, Beatriz; Santos-Buelga, Celestino; Ferreira, Isabel C.F.R.Atualmente, existe uma grande procura de alimentos com ingredientes naturais em substituição de aditivos sintéticos que têm sido associados, em determinadas circunstâncias, a alguns efeitos tóxicos [1]. Neste trabalho, preparou-se um extrato aquoso por decocção de Foeniculum vulgare Mill. (funcho) que, após caracterização por HPLC-DAD-ESI/MS, revelou a presença de cinco flavonoides (sendo o maioritário o quercetin-3-O-glucósido) e doze ácidos fenólicos (sendo o maioritário o ácido 5-Ocafeoilquínico). O mesmo extrato revelou um enorme potencial antioxidante (efeito captador de radicais livres DPPH, poder redutor e inibição da peroxidação lipídica) e antimicrobiano (contra bactérias como Salmonella typhimurium e Bacillus cereus, e fungos como Aspergillus niger, A. versicolor e Penicillium funiculosum), o que suscitou o seu potencial de utilização como ingrediente bioativo na funcionalização de alimentos. Assim, procedeu-se à sua incorporação (atendendo ao EC25 =0,35 mg/mL obtido no ensaio de DPPH) em requeijões (preparados na empresa Queijos Casa Matias Lda.). Os resultados mostraram que a presença do extrato não alterou significativamente as características nutricionais (incluindo macronutrientes, valor energético e perfil em ácidos gordos) das amostras controlo (requeijão sem esse ingrediente), no entanto parece aumentar o amarelecimento (parâmetro da cor, b*) após 7 dias de armazenamento. Verificou-se ainda que, após duas semanas de armazenamento apenas as amostras controlo apresentaram sinais de degradação. Além disso, conseguiu-se provar que a incorporação do extrato de funcho conferiu propriedades antioxidantes ao requeijão. Os resultados obtidos provam assim que o extrato fenólico obtido através da decocção de funcho pode ser utilizado como conservante e agente bioativo natural em requeijões.
- Ananas comosus L. bio-waste as a source of bioactive compounds with health benefitsPublication . Moreira, Bruna; Caleja, Cristina; Finimundy, Tiane C.; Pinela, José; Calhelha, Ricardo C.; Ferreira, Isabel C.F.R.; Barros, LillianPineapple ( Ananas comosus L.) is a fruit appreciated and consumed worldwide not only because it is recognized for nutritional properties, but also for the beneficial characteristics that help in the development of the organism [1]. Although only the pulp is consumed, several studies have been exploring different parts of the fruit, as they have high amounts of bioactive compounds of interest. Thus, and since the food industry annually produces tons of waste that are not properly used [2], this work aimed at the characterization of the pineapple peel and crown in order to enhance this bio-waste and a circular bioeconomy. Heat-assisted hydroethanolic extraction was used to recover compounds subsequently identified and quantified by High-Performance Liquid Chromatography coupled with a diode array detector and electrospray ionization mass spectrometry (HPLC-DAD-ESI/MS). Twenty phenolic compounds were identified in both peel and crown extracts, among them, phenolic acids and flavonoids. The main detected compounds were caffeic acid derivatives, namely caffeine putrescine and flavones such as apigenin 6,8- C -diglucoside. The antioxidant activity of the extracts was tested and proved through two in vitro tests: the lipid peroxidation inhibition test (TBARS) and the oxidative hemolysis inhibition test (OxHLIA). The antiproliferative activity of both extracts was evaluated in tumor and non-tumor cell lines using the sulforhodamine B method, and the anti-inflammatory activity in lipopolysaccharide-activated RAW 264.7 macrophages by the ability to inhibit NO production. The results showed that both extracts had an excellent performance in the cell-based tests of antioxidant activity, highlighting the lower EC 50 values and consequently greater activity for the bark extract. The same trend was seen in the tests of anti-tumor activity, with none of the extracts showing toxicity up to the maximum concentration tested (GI 50 > 400 μg/mL). This study confirms the potential application of pineapple bio-residues, especially the peel, in the food industry as a source of compounds with bioactive properties, contributing to the valorization of this bio-waste.
- Antifungal activity of Chamomilla recutita L. and Foeniculum vulgare Mill. aqueous extracts in cottage cheesePublication . Alves, Maria José; Heleno, Sandrina A.; Caleja, Cristina; Oliveira, Joana; Pimentel, Vanessa; Kostić, Marina; Soković, Marina; Ferreira, Isabel C.F.R.Introduction: The use of natural substances with fungicide, insecticide and herbicide properties is the focus of intensive research in order to develop sustainable foodstuff. Objectives: To assess the inhibition effect of Chamomilla recutita and Foeniculum vulgare aqueous extracts, against yeasts and fungi directly in cottage cheese along storage at 4ºC (t0, after 7 days (t7) and after 14 (t14) days). Methodology: Cottage cheese was incorporated with aqueous extracts of C. recutita and F. vulgare. Yeasts and molds were grown in Dichloran Rose Bengal Chloramphenicol medium (Agar-DRBC). The antifungal activity was evaluated by the microdilution method in plate. Results: After observation of the cottage cheese cultures in specific medium at t0, it can be stated that it was not verified any growth neither in control nor in the samples incorporated with the plant extracts. However, at t7 and t14 it was observed growth of yeasts and fungi in control, while the samples with C. recutita and F. vulgare revealed no growth of yeasts in Agar-DRBC. Thus, we note that both C. recutita and F. vulgare inhibited the growth of yeasts and fungi directly in the cottage cheese. Fungal colonies present in curd control were identified and verified as being the yeast Candida krusei and filamentous fungus Cladospoirium herbarum. C. recutita and F. vulgare showed antifungal activity against C. krusei (MIC = 50 mg/ml and 25 mg/ml, respectively) and C. herbarum (MIC = 100 mg/ml in both cases). Conclusion: The two tested plant extracts were able to inhibit the growth of the mentioned yeast and fungi, being able to increase the shelf life of the cottage cheese.
- Aplicação em waffles de um corante natural obtido de frutos de Arbutus unedo L.Publication . Jiménez López, Cecília; Caleja, Cristina; Corrêa, Rúbia C.G.; Dias, Maria Inês; Prieto Lage, Miguel A.; Barreiro, M.F.; Barros, Lillian; Ferreira, Isabel C.F.R.Os corantes são um dos aditivos mais importantes em termos de marketing, uma vez que a cor pode influenciar diretamente as escolhas e preferências dos consumidores [1]. No entanto, têm sido descritos alguns efeitos indesejáveis de determinados corantes artificiais. Contrariamente, os corantes naturais (e.g. ricos em compostos antociânicos) são genericamente considerados inofensivos, para além de poderem proporcionar efeitos bioativos [2]. Neste estudo, um extrato rico em antocianinas, obtido a partir de frutos de Arbutus unedo L. (medronho), foi aplicado como corante natural num produto de pastelaria. Para a preparação do extrato, otimizou-se o processo de extração utilizando duas metodologias: extração assistida por calor e extração assistida por ultrassons, de forma a obter as condições que maximizam a concentração de antocianinas. Foi aplicanda uma metodologia de superfície de resposta, seguindo um delineamento experimental de 5 níveis e as respostas foram obtidas através de HPLC-DAD-ESI/MS, onde foram identificados três compostos antociânicos; a cianidina-3-glucósido foi a molécula maioritária. A técnica de extração assistida por calor demostrou ser o método mais eficaz para a extração de antocianinas, produzindo 51,2% de extrato, com um teor total de antocianinas de 382,4 μg/g fruto seco e 744,6 μg/g de extrato, nas condições ótimas de 5 minutos, 90ºC, 80% de etanol e 15 g/L de razão sólido: líquido. Posteriormente, o extrato foi incorporado em waffles, tendo-se avaliado a sua composição em macronutrientes, bem como em açúcares livres e ácidos gordos, ao longo de 6 dias de armazenamento. Os resultados obtidos demonstraram que a incorporação do extrato não causou alterações nos componentes nutricionais. Validam também a possibilidade de utilizar frutos de A. unedo como fonte de compostos antociânicos muito interessantes para utilização como corantes alimentares naturais.
- Aplicação em waffles de um corante natural obtido de frutos de Arbutus unedo L.Publication . Jiménez López, Cecília; Caleja, Cristina; Corrêa, Rúbia C.G.; Dias, Maria Inês; Prieto Lage, Miguel A.; Barreiro, M.F.; Barros, Lillian; Ferreira, Isabel C.F.R.Os corantes são um dos aditivos mais importantes em termos de marketing, uma vez que a cor pode influenciar diretamente as escolhas e preferências dos consumidores [1]. No entanto, têm sido descritos alguns efeitos indesejáveis de determinados corantes artificiais. Contrariamente, os corantes naturais (e.g. ricos em compostos antociânicos) são genericamente considerados inofensivos, para além de poderem proporcionar efeitos bioativos [2]. Neste estudo, um extrato rico em antocianinas, obtido a partir de frutos de Arbutus unedo L. (medronho), foi aplicado como corante natural num produto de pastelaria. Para a preparação do extrato, otimizou-se o processo de extração utilizando duas metodologias: extração assistida por calor e extração assistida por ultrassons, de forma a obter as condições que maximizam a concentração de antocianinas. Foi aplicanda uma metodologia de superfície de resposta, seguindo um delineamento experimental de 5 níveis e as respostas foram obtidas através de HPLC-DAD-ESI/MS, onde foram identificados três compostos antociânicos; a cianidina-3-glucósido foi a molécula maioritária. A técnica de extração assistida por calor demostrou ser o método mais eficaz para a extração de antocianinas, produzindo 51,2% de extrato, com um teor total de antocianinas de 382,4 μg/g fruto seco e 744,6 μg/g de extrato, nas condições ótimas de 5 minutos, 90ºC, 80% de etanol e 15 g/L de razão sólido: líquido. Posteriormente, o extrato foi incorporado em waffles, tendo-se avaliado a sua composição em macronutrientes, bem como em açúcares livres e ácidos gordos, ao longo de 6 dias de armazenamento. Os resultados obtidos demonstraram que a incorporação do extrato não causou alterações nos componentes nutricionais. Validam também a possibilidade de utilizar frutos de A. unedo como fonte de compostos antociânicos muito interessantes para utilização como corantes alimentares naturais
- Arbutus unedo L. and Ocimum basilicum L. as sources of natural preservatives for food industry: A case study using loaf breadPublication . Takwa, Sallawi; Caleja, Cristina; Barreira, João C.M.; Soković, Marina; Achour, Lotfi; Barros, Lillian; Ferreira, Isabel C.F.R.; Takwa, SallawiThe aim of this work was to demonstrate the antioxidant potential, antimicrobial and the absence of toxicity of the ethanol extracts obtained from strawberry tree fruits and basil leaves, using optimal conditions. Subsequently, the extracts rich in catechin, from strawberry tree fruits, and rosmarinic acid from basil leaves, were incorporated as natural ingredients in loaf bread samples, with two objectives: to functionalize bread, introducing bioactive properties; and as natural ingredients with preservation capacity. Three more groups: control (without addition of any additive), bread incorporated with ascorbic acid - E300 and bread incorporated with potassium sorbate - E202 and for each group were 3 different times were analyzed: immediately after incorporation and after 3 and 7 days. Both natural extracts presented antioxidant activity, without toxicity up to the maximal tested dose (400 µg/mL), and the main compounds present were catechin and rosmarinic acid, respectively. The breads incorporated with the natural extracts, especial b asil, presented a higher antioxidant capacity than the loaf breads incorporated with ascorbic acid and potassium sorbate. Overall, the obtained results demonstrate that these extracts could be used in the development of new bread replacing the synthetic preservatives, without interfering with nutritional characteristics.
- Arbutus unedo L. and Ocinum basilicum L. as sources of natural ingredients for bread functionalizationPublication . Sallawi, Takwa; Caleja, Cristina; Achour, Lotfi; Barros, Lillian; Ferreira, Isabel C.F.R.The overwhelming growth of the world population is causing direct consequences on food demands, which has forced the food industry to apply synthetic additives in order to meet the needs of the consumer and ensuring the global quality of the food products including aspect, texture and flavor. However, due to the publication of some studies describing adverse effects associated with these synthetic additives, the natural ones have been gaining increasing interest. Arbutus unedo L. (strawberry tree) fruits and Ocimum basilicum L. (basil) leaves, are important sources of bioactive natural molecules, especially phenolic compounds, including flavan-3- ols and phenolic acids, respectively . The aim of this work was to demonstrate the antioxidant potential (free radical scavenging effect, reducing power and inhibition of lipid peroxidation) and the absence of toxicity (porcine liver primary cells) of ethanol extracts, obtained from the previously mentioned plants by using optimal conditions. Subsequently, the extracts were incorporated as natural ingredients in loaf bread samples, with two objectives: to functionalize loaf bread, introducing bioactive properties; and as natural ingredients with preservation capacity. Five groups of loaf bread samples were prepared: i) control (without natural or synthetic additives); ii) loaf bread incorporated with strawberry tree extract; iii) loaf bread incorporated with basil extract; iv) loaf bread incorporated with ascorbic acid- E300 (natural additive); and v) loaf bread incorporated with potassium sorbate- E202 (synthetic additive). Both extracts (strawberry tree fruits and basil leaves) presented antioxidant activity (EC50 values lower the 595 and 351 μg/mL, respectively), without toxicity up to the maximal tested dose, and the main compounds present were (+)-catechin and rosmarinic acid, respectively. The introduction of both natural and synthetic additives in loaf bread when compared to the control sample, did not cause significant changes, neither in pH values, nor in color or any of the evaluated nutritional parameters. The obtained results demonstrate that these extracts could be used in the development of new loaf bread replacing the synthetic preservatives, without interfering with the physical and nutritional characteristics.
- Arbutus unedo L. e Ocimum basilicum L. como conservantes naturais de pãoPublication . Sallawi, Takwa; Caleja, Cristina; Barreira, João C.M.; Soković, Marina; Achour, Lotfi; Barros, Lillian; Ferreira, Isabel C.F.R.Atualmente, existe uma preocupação da indústria alimentar na substituição de aditivos sintéticos por ingredientes naturais. Os extratos naturais obtidos a partir de plantas surgem como possíveis alternativas aos conservantes sintéticos, nomeadamente dos antioxidantes. Neste trabalho, pretendeu-se comprovar a eficácia de extratos ricos em catequina, obtido a partir de frutos de Arbutus unedo L. (medronho) e em ácido rosmarínico obtido a partir de folhas de Ocimum basilicum L. (manjericão), como conservantes naturais de pão, comparando a sua eficácia com aditivos sintéticos normalmente aplicados a produtos de panificação. Após a avaliação das propriedades antioxidantes (valores EC50 do efeito bloqueador de radicais de DPPH = 595 e 351 μg/ mL, para medronho e manjericão, respetivamente) e antimicrobianas (contra 8 bactérias e 8 fungos) e confirmação da ausência de citoxicidade (numa cultura primária de células de fígado), os extratos ricos em (+)-catequina e ácido rosmarínico foram incorporados no pão. O seu efeito foi comparado com o ácido ascórbico (E300), o sorbato de potássio (E202) e com uma amostra controlo (pão sem aditivos) imediatamente após a incorporação e após 3 e 7 dias de armazenamento, à temperatura ambiente e protegidos da luz. Os pães aditivados com os extratos naturais, especialmente de manjericão, apresentaram maior capacidade antioxidante do que os pães com ácido ascórbico e sorbato de potássio, tendo todos mantido as suas propriedades nutricionais. Em geral, os resultados obtidos demonstraram que os extratos podem ser utilizados no desenvolvimento de pão, substituindo os conservantes sintéticos, sem interferir nas características físicas e nutricionais dos produtos finais.