Percorrer por autor "Oliveira, Beatriz"
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- Add-value of Lactarius deliciosus and Macrolepiota procera wild mushrooms due to their nutritional and nutraceutical potentialPublication . Fernandes, Ângela; Oliveira, Beatriz; Martins, Anabela; Ferreira, Isabel C.F.R.This study describes the nutritional and nutraceutical potential of two species of wild edible mushrooms (Lactarius deliciosus and Macrolepiota procera) commonly consumed in the region of Trás-os-Montes, Northeast Portugal. The nutritional parameters analyzed were moisture, ash, fat, proteins, carbohydrates and energetic contribution. Free sugars and fatty acids were also determined by high performance liquid chromatography coupled with a refractive index detector (HPLC/RI) and gas chromatography coupled with a flame ionization detector (GC/FID), respectively. Macronutrient profile revealed that the studied species are rich sources of carbohydrates, proteins and energy, revealing low fat content. Mannitol and trehalose were the most abundant sugars in both species. The main fatty acid found in M. procera was linoleic acid, while stearic acid was the most abundant in L. deliciosus. The nutraceutical potential was also evaluated through antioxidant properties measured by DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging activity, reducing power, inhibition of β-carotene bleaching and inhibition of LPO using thiobarbituric acid reactive substances (TBARS). The mentioned assays showed and high antioxidant activity for both samples species. Phenolic acids and related compounds were analysed by HPLC coupled to diode array detection (HPLC/DAD) and p-Hydroxybenzoic acid was found in L. deliciosus and cinnamic acid in M. procera.
- Adulteration of Dietary Supplements by the Illegal Addition of Synthetic Drugs: a reviewPublication . Rocha, Tiago; Amaral, Joana S.; Oliveira, BeatrizIn the last few years, the consumption of dietary supplements, especially those having plants as ingredients, has been increasing due to the common idea that they are natural products posing no risks to human health. In the European Union and the United States, dietary supplements are legally considered as foods/special category of foods, thus are not being submitted to any safety assessment prior to their commercialization. Among the issues that can affect safety, adulteration by the illegal addition of pharmaceutical substances or their analogs is of major concern since unscrupulous producers can falsify these products to provide for quick effects and to increase sales. This review discusses the various classes of synthetic drugs most frequently described as being illegally added to dietary supplements marketed for weight loss, muscle building/sport performance and sexual performance enhancement. Information regarding regulation and consumption is also presented. Finally, several conventional and advanced analytical techniques used to detect and identify different adulterants in dietary supplements and therefore also in foods, with particular emphasis on plant food supplements, are critically described. This review demonstrates that dietary supplement adulteration is an emerging food safety problem and that an effective control by food regulatory authorities is needed to safeguard consumers.
- Advances in Authenticity Testing for Meat SpeciationPublication . Amaral, Joana S.; Meira, L.; Oliveira, Beatriz; Mafra, IsabelNowadays, and particularly after the horse meat scandal in Europe, consumers are increasingly aware of the problem of food adulteration and consequently demand clear and reliable information about the composition of foods they are buying and eating. Meat, a highly appreciated premium source of protein, is among the foods most prone to suffer adulteration for economic gain. According to EU legislation laying down the general principles and requirements of food law (European Commission, 2002) and EU labeling regulations (European Commission, 2001), meat products should be accurately labeled regarding their species content, with food adulteration and misleading information being considered illegal. However, because of its high demand and value, frauds in the meat industry and retail markets have become a widespread problem, especially in ground and comminuted meat products.
- Advances in isoflavone profile characterisation using matrix solid-phase dispersion coupled to HPLC/DAD in medicago speciesPublication . Visnevschi-Necrasov, Tatiana; Barreira, João C.M.; Cunha, Sara C.; Pereira, Graça; Nunes, Eugénia; Oliveira, BeatrizAnalytical methods used in phytochemistry analysis are limited by the sample preparation step, which should ideally be fast, accurate, ecofriendly and achievable using low quantities of the sample. Matrix solid-phase dispersion (MSPD) may be a good alternative for combining extraction and purification procedures, thereby reducing the indicated limitations. Objective-Applying an MSPD extraction procedure coupled to high-performance liquid chromatography diode-array detection (HPLC/DAD) as an alternative methodology to evaluate isoflavone profiles. Methods-Isoflavone profiles were determined for the leaves of nine species of Medicago in the late flower phenological stage (one or more nodes with 50% open flowers, no seed pods). Extraction was performed following MSPD, and isoflavone profiles were characterised using HPLC/DAD. The quantified amounts were compared with previous results in different species commonly recognised as good sources of isoflavones. Results-Formononetin was the major isoflavone in most species, except M. polymorpha and M. truncatula. The isoflavone amounts were significantly different among the assayed species, with M. orbicularis and M. arabica as the major isoflavone sources, while M. rigidula presented the lowest contents. Furthermore, the detected differences allow electing the best species as a primary source of a specific isoflavone. Conclusion-The MSPD allowed good extraction efficiency, reproducibility and recovery. Some of the species showed relevant isoflavone contents, even when compared with acknowledged plant sources such as soy or red clover. To the best of our knowledge the results presented are reported for the first time in these species.
- Agaricus blazei Murril - a potential ingredient for nutraceutical outcomesPublication . Taofiq, Oludemi; Rodrigues, Francisca; Barros, Lillian; Calhelha, Ricardo C.; González-Paramás, Ana María; Barreiro, M.F.; Oliveira, Beatriz; Ferreira, Isabel C.F.R.The concept of bio-economy has emerged to overcome some sustainability challenges, and this involves conversion of agricultural residues and waste streams into high value-added products that can be utilized as ingredients for several bio-based industrial processes, delivering both economic growth, scientific interest and a better environment. The present work was carried out to re-utilize discarded Agaricus blazei Murill. Its nutritional composition was evaluated and ethanolic extracts were prepared by Soxhlet extraction to be further evaluated for their anti-inflammatory, anti-tyrosinase and cytotoxic properties against different tumor cell lines (SRB assay). MTT and LDH assays were also used to determine cell viability and cell death respectively in Caco-2 and HT29 cells lines. Essential nutrients such as carbohydrates, proteins and fat, were found; twenty fatty acids were detected, sugars (mannitol and trehalose), α-tocopherol and oxalic acid were also present. The extracts, up to 100 μg/mL, were able to maintain viability of Caco-2 and HT29 cells. The extracts also presented anti-tyrosinase activity (EC50 1.33±0.02 mg/mL) and with no toxicity in tumor cells. The results obtained suggested that the extracts obtained from Agaricus blazei Murill residues can be utilized as an inexpensive and sustainable source of nutraceutical and functional food ingredients.
- Agaricus blazei Murrill from Brazil: An ingredient for nutraceutical and cosmeceutical applicationsPublication . Taofiq, Oludemi; Rodrigues, Francisca; Barros, Lillian; Peralta, Rosane M.; Barreiro, M.F.; Ferreira, Isabel C.F.R.; Oliveira, BeatrizOperations for sorting mushrooms at the industrial level usually generate large amounts of bio-residues not conforming to strict morphological criteria for commercial purposes, even though their biological content is not compromised. In this context, the present work aimed at evaluating the potential for reutilizing industrially discarded Agaricus blazei Murill (ABM). Thus, the content of essential nutrients and the chemical composition were determined, and MTT and LDH assays were used to evaluate the viability and cell death of Caco-2 and HT29 cell lines of an ethanolic extract prepared from ABM (preliminary safety tests for nutraceutical applications). The extract was incorporated into a semi-solid base cosmetic cream and cell viability effects of the extract, and of the final cream formulation, on a keratinocyte cell line (HaCaT) were studied (preliminary safety tests for cosmeceutical applications). Essential nutrients, such as proteins and carbohydrates, and a low fat content were determined for ABM. Twenty-two fatty acids were detected, with polyunsaturated fatty acids (PUFA) (∼53%) being the most abundant fraction. The cell viabilities of Caco-2 and HT29 cells were maintained up to 100 μg mL−1. After incorporation into the base cream, a formulation with a pale yellow colour and favourable pH was obtained. The cell viability of HaCaT cells in the presence of the extract and the final cream formulation was maintained in a concentration dependent manner, which indicates the safety of this extract for cosmeceutical applications. The results suggest that ABM residues can be used as an inexpensive and sustainable source of nutraceutical and cosmeceutical ingredients.
- Agri-food surplus, waste and loss as sustainable biobased ingredients: a reviewPublication . Rodrigues, Joana P.B.; Liberal, Ângela; Petropoulos, Spyridon Α.; Ferreira, Isabel C.F.R.; Oliveira, Beatriz; Fernandes, Ângela; Barros, LillianEnsuring a sustainable supply of food for the world’s fast growing population is a major challenge in today’s economy, as modern lifestyle and increasing consumer concern with maintaining a balanced and nutritious diet is an important challenge for the agricultural sector worldwide. This market niche for healthier products, especially fruits and vegetables, has increased their production, consequently resulting in increased amounts of agri-food surplus, waste, and loss (SWL) generated during crop production, transportation, storage, and processing. Although many of these materials are not utilized, negatively affecting the environmental, economic, and social segments, they are a rich source of valuable compounds that could be used for different purposes, thus preventing the losses of natural resources and boosting a circular economy. This review aimed to give insights on the efficient management of agri-food SWL, considering conventional and emerging recovery and reuse techniques. Particularly, we explored and summarized the chemical composition of three worldwide cultivated and consumed vegetables (carrots, broccoli and lettuce) and evaluate the potential of their residues as a sustainable alternative for extracting value-added ingredients for the development of new biodynamic products
- Alimentos tradicionais e inovação: uso de atmosferas modificadas e radiação ionizante na conservação da qualidade das azedasPublication . Pinela, José; Barreira, João C.M.; Barros, Lillian; Cabo Verde, Sandra; Antonio, Amilcar L.; Oliveira, Beatriz; Carvalho, Ana Maria; Ferreira, Isabel C.F.R.Os vegetais embalados prontos a comer têm tido uma crescente aceitação por parte do consumidor por atenderem aos requisitos contemporâneos de conveniência, segurança e salubridade. O crescimento deste setor tem levado à introdução de novos produtos e à adoção de tecnologias de conservação mais eficientes, seguras e sustentáveis. Neste sentido, este estudo teve como objetivo avaliar a eficácia de diferentes atmosferas de embalamento e de diferentes doses de radiação ionizante na conservação de parâmetros de qualidade das azedas (Rumex induratus Boiss. & Reut.) durante um armazenamento refrigerado. Exemplares silvestres de azedas foram lavados em água corrente e uma porção foi imediatamente analisada (controlo não armazenado). O restante material fresco foi embalado em atmosferas enriquecidas em azoto, árgon, ar (atmosfera controlo passiva) e sob vácuo, utilizando filmes de polietileno de baixa densidade. As amostras embaladas em atmosfera passiva foram submetidas a diferentes doses de irradiação gama (até 6 kGy) numa câmara de cobalto-60. Todas as amostras foram armazenadas a 4°C durante 12 dias e posteriormente analisadas. A cor foi medida com um colorímetro; o teor em água, proteínas, lípidos, glúcidos e cinzas e o valor energético foram determinados seguindo métodos oficiais de análise de alimentos; os perfis em açúcares, ácidos orgânicos, tocoferóis e ácidos gordos foram analisados por técnicas cromatográficas; e as propriedades antioxidantes avaliadas recorrendo a ensaios químicos e bioquímicos in vitro. Ambos os tratamentos tiveram efeitos positivos e negativos na qualidade das amostras. Tendo em conta a contribuição de todos os parâmetros analisados, foi possível concluir que as atmosferas enriquecidas em árgon foram uma boa opção para conservar a qualidade global das azedas durante o armazenamento refrigerado; enquanto a dose de 6 kGy foi adequada para manter níveis elevados de ácidos gordos polinsaturados (PUFA). Além destes resultados, este estudo destacou o potencial das azedas na indústria dos alimentos minimamente processados.
- Alimentos tradicionais e inovação: Uso de atmosferas modificadas e radiação ionizante na conservação da qualidade das azedasPublication . Pinela, José; Barreira, João C.M.; Barros, Lillian; Cabo Verde, Sandra; Antonio, Amilcar L.; Oliveira, Beatriz; Carvalho, Ana Maria; Ferreira, Isabel C.F.R.O crescimento do setor dos vegetais embalados prontos a comer tem levado à introdução de novos produtos e à adoção de tecnologias de conservação mais eficientes, seguras e sustentáveis. Neste sentido, este estudo teve como objetivo avaliar a eficácia de diferentes atmosferas de embalamento e de diferentes doses de radiação ionizante na conservação de azedas (Rumex induratus) armazenadas a 4°C durante 12 dias. Ambos os tratamentos tiveram efeitos positivos e negativos na qualidade das amostras. Tendo em conta a contribuição de todos os parâmetros analisados, foi possível concluir que o embalamento a vácuo foi a melhor opção para conservar a qualidade global das amostras durante o armazenamento, seguido do embalamento em atmosfera enriquecida em árgon. Este estudo destacou também o potencial das azedas na indústria dos alimentos minimamente processados.
- Almond (Prunus dulcis) as a good source of health beneficial fatty acidsPublication . Barreira, João C.M.; Casal, Susana; Ferreira, Isabel C.F.R.; Oliveira, Beatriz; Pereira, J.A.