Browsing by Author "Silva, Carla Sousa e"
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- Agro-food wastes: valorization of lychee (Litchi chinensis) peelsPublication . Ferchal, Clemence; Silva, Carla Sousa e; Ferreira da Vinha, AnaBackground: Tropical fruits represent one of the most important crops in the world. Moreover, currently, food security is a growing problem due to the depletion of natural resources and increasing population, which has led to a gap between production and consumption (1). Nowadays, medicine has started to pay great attention to functional food, which displays an additional function related to health promotion or disease prevention. In fact, phytochemicals present in fruit byproducts (peel and seeds) are generally significantly higher than in their respective edible tissues (pulp), suggesting these wastes to be potential sources for isolating bioactive compounds or as nutraceuticals ingredients for new food products (2). Methods: Lychee (Litchi chinensis) is a very popular fruit, currently consumed worldwide. The peel and seed represent 50% of the fruit, which is considered high. However, when processed properly, such waste can generate other products as extracts and flours, contributing to its use in food, pharmaceutical and cosmetic industries. Selected fruits were washed, weighed and separated into peel, pulp and seed. The peel was lyophilized, ground, and stored protected from light until the time of analysis. Proximate composition of lychee peel flour was performed according to the methods AOAC (3), and dietary fiber, determined using enzymatic kit Sigma®, followed the technique proposed by (3). The total energy value (TEV) was also calculated. Results: Total carbohydrates and TEV were high (60 g/100 g and 318 kcal/100 g, respectively), presenting low content of proteins and lipids. Lychee peel flour presented 20 g/100 g dietary fiber. The Reference Daily Intake (RDI) is 25 g fiber (4); thus, this flour may be considered a potential fiber source, to be integrated in new products. Conclusions: It is desirable to find proper food applications for fruits peel for helping the environment through sustainability and creating new value-added food products.
- Alimentos funcionais: uma tendência de mercadoPublication . Silva, Carla Sousa e; Passos, Ana Rita; Pereira, Ana Filipa; Ferreira da Vinha, Ana; Ana, NunesA mudança dos hábitos e costumes da sociedade moderna que tem vindo a acontecer nas últimas décadas, conduziu a uma alteração dos padrões alimentares e, consequentemente, a consumidores mais exigentes e atentos aos benefícios que cada género alimentício aporta. Como resposta a esta situação, a indústria alimentar reforçou a sua política de investigação, surgindo um novo tipo de alimentos, denominados alimentos funcionais, os quais são caracterizados como alimentos comuns, integrados na dieta e capazes de produzir benefícios específicos para a saúde. As substâncias biologicamente ativas presentes nos alimentos funcionais podem ser classificadas em: probióticos e prebióticos, alimentos sulfurados e azotados, pigmentos naturais e vitaminas, compostos fenólicos, ácidos gordos polinsaturados e fibras alimentares. Este trabalho teve como objetivo realizar uma revisão bibliográfica fundamentada que sustente a importância dos alimentos funcionais como géneros alimentícios integrantes da dieta alimentar, apresentando as diferentes classes de compostos bioativos que os integram e divulgando os seus efeitos benéficos à saúde. A pesquisa de informação para a realização deste trabalho foi efetuada recorrendo aos motores de busca PubMed, Science Direct, Google Scholar e Scielo. As palavras-chave utilizadas foram, maioritariamente, alimento funcional, ingrediente funcional, componentes bioativos, prebióticos, consumo. A pesquisa bibliográfica teve por base artigos de revisão e estudos experimentais publicados, relacionados com o tema deste trabalho, limitando-se a procura a textos escritos em inglês, espanhol e português. Uma vez que esta revisão pretendeu abranger a evolução dos alimentos funcionais, desde o aparecimento do conceito dos mesmos, no Japão, na década de 80, até aos dias de hoje, a pesquisa realizada teve como limites temporais os anos de 1995 até à atualidade.
- Antioxidant activity of the garlic (Allium sativum L.) submitted to different technological processesPublication . Silva, Carla Sousa e; Novo, Catarina; Ferreira da vinha, Ana
- Aspetos nutricionais e propriedades biológicas das sementes de papoila e de quinoaPublication . Ferreira da Vinha, Ana; Silva, Carla Sousa e; Matos, Carla; Moutinho, CarlaA dieta alimentar permite ao indivíduo consumir diariamente substâncias nutritivas fundamentais para o seu desenvolvimento e sobrevivência. Contudo, quando a sua ingestão é nutricionalmente desequilibrada ou escassa, o metabolismo humano poderá atingir um estado de desnutrição e, consequentemente, promover o aparecimento de distúrbios metabólicos e/ou doenças crónicas. Com a consciencialização destes problemas verificou-se, nos últimos anos, uma crescente tendência para o consumo de alimentos funcionais ou substâncias nutracêuticas. Muitos destes alimentos e ingredientes são de origem vegetal, apresentando elevados teores de fibra, vitaminas, minerais, ácidos gordos polinsaturados, proteínas, compostos bioativos, entre outros. Consequentemente, uma maior atenção tem sido dada à utilização de sementes, as quais, na sua maioria, não são utilizadas pela indústria alimentar, nem pela população em geral. O aproveitamento das sementes traz maior valor económico à produção agrícola, além de contribuir para a formulação de novos produtos alimentares e diminuir o desperdício industrial. Neste artigo pretende-se efetuar uma revisão bibliográfica sobre o aporte nutricional e as propriedades biológicas de sementes de papoila e de quinoa, as quais têm tido elevada aceitação por parte do consumidor em geral, quer como ingredientes, quer como alimentos.
- Avaliação da utilização da espectrofotometria de UV/Vis na quantificação de antibióticos em extractos de leite de vacaPublication . Guedes, Cátia; Matos, Carla; Moutinho, Carla; Silva, Carla Sousa eA comercialização da maior parte dos alimentos é precedida por um processamento complexo,o qual necessita de ser devidamente monitorizado, de forma a controlar a presença de substâncias nocivas. no entanto, estas substâncias, designadamente antibióticos, são necessárias no combate de diversas patologias veterinárias, pelo que são administradas aos animais de consumo. este estudo foi desenvolvido com o objectivo de testar e optimizar um método de extracção de resíduos de antibióticos do leite de vaca gordo pasteurizado. The marketing of most food is preceded by a complex process, which needs to be properly monitored in order to supervise the presence of harmful substances. However, these substances, including antibiotics that are administrated to consumption animals, are necessary in combating of various veterinary diseases. this study was developed with the aim to test and optimize a method for extraction of antibiotic residues in cow’s pasteurized milk.
- Avocado and its by-products: natural sources of nutrients, phytochemical compounds and functional propertiesPublication . Ferreira da Vinha, Ana; Silva, Carla Sousa e; Soares, Marta De Oliveira; Barreira, SérgioAvocado (Persea americana Mill.) is a tropical and subtropical fruit that is native to Mexico and Central America. This fruit is gaining increasing worldwide acceptance and has received extensive marketing and a wide distribution due to its relevant nutritional benefits for human health. This work presents relevant information on the production, composition and application of avocado, with an emphasis on its by-products, focusing on the proper use of waste and the possibility of monetizing waste for nutritional and environmental purposes. The entire avocado is rich in bioactive compounds (pulp, peel and seed) and presents several health benefits, such as antimicrobial, antioxidant and anticancer activities, as well as dermatological uses and others. Therefore, several food grade ingredients can be obtained from avocado wastes, particularly premium-grade fats or extracts with a high functional power. Studies should continue to identify the profiles and phytochemicals available to the business sector, which can also be implemented to valorize the nutritional and functional potential of avocado seeds and peels.
- BBr3-assisted cleavage of most ethers does not follow the commonly assumed mechanismPublication . Silva, Carla Sousa e; Silva, Pedro J.Density‐functional computations were used to probe the reaction mechanism of BBr3‐assisted ether cleavage. After the initial formation of an ether–BBr3 adduct, secondary and tertiary alkyl ethers are cleaved through Br– transfer from the activated BBr3 to the alkyl moiety, as postulated in the literature. In contrast, all other ethers studied react through a novel pathway involving two ether–BBr3 adducts, one of which acts as Br– donor, and the second as the reaction substrate. The identification of the novel bimolecular mechanism for this classical reaction has further applications, because it implies that BBr3‐assisted ether cleavage may become impossible if the ether is surrounded by bulky portions of the molecule that prevent the approach of the attacking BBr3 adduct. Our data also allow the construction of an order of reactivity of alkyl ether deprotection: isopropyl, benzyl, tertiary alkyl, allyl, isobutyl and ethyl can be removed sequentially as their bromo derivatives; phenyl, cyanomethyl and chloromethyl groups can be sequentially removed as their corresponding alcohols.
- Bioactive compounds and scavenging capacity of Adansonia digitata L. (Baobab fruit) pulp extracts against ROS and RNS of physiological relevancePublication . Ferreira da Vinha, Ana; Costa, Anabela S.G.; Pimentel, Filipa B.; Santo, Liliana Espírito; Silva, Carla Sousa e; Freitas, Marisa; Fernandes, Eduarda; Oliveira, M. Beatriz P.P.Background: Baobab fruit is valued for its nutritional and medicinal benefits. Although it is acknowledged that baobab pulp is beneficial for health, studies that link its nutraceutical properties to the ability to eliminate reactive species (ROS and RNS) are scarce. Methods: The nutritional profile and the antioxidant properties of baobab pulp extracts from Angola were evaluated. Thus, for the first time, the evaluation of in vitro scavenging capacity against the most physiologically relevant reactive oxygen species (ROS) and reactive nitrogen species (RNS) were the focus of inves tigation. Results: Angolan fruit pulp presented high contents of ash (8.0%) and total dietary fiber (52%). Vitamin E content was reported for the first time in fruit pulp. Green solvents were used to quantify bioactive compounds and antioxidant activity. Hydroalcoholic extracts exhibited the high est contents of phenolics (1573.0 mg/100 g) and flavonoids (768.7 mg/100 g). Thus, hydroalcoholic extracts showed higher antioxidant activity, and higher scavenging capacity for ROS (O2•−, H2O2, HOCl, ROO•) and RNS (•NO, ONOO−), being most active for •NO and ONOO−. Conclusion: For the first time, Angolan baobab fruit was described in respect to its nutritional contribution as well as its positive antioxidant effects, both as a functional food and as a nutraceutical ingredient.
- Biochemical changes in cardiovascular diseasesPublication . Moutinho, Carla; Matos, Carla; Silva, Carla Sousa e
- Biological activities and valuable bioactive compounds from portuguese medicinal plantsPublication . Ferreira da Vinha, Ana; Silva, Carla Sousa eCurrently, there are more than 85,000 plant species that have been documented for medical use globally. This implies, plant derived natural products hold great promise for discovery and development of new pharmaceuticals in diverse human ailments. The lack of effective pharmaceutical formulas and the resistance created by current antibiotic pathogens, as well as oxidative stress new therapeutic agents from plants. In fact, several studies have shown that medicinal plants possess antioxidant properties due largely to their phytochemical profile. Endemic plants can be a source of new bioactive compounds able to prevent several diseases such as cancer, diabetes, hypertension, and Alzheimer’s disease by combating oxidative stress and its associated pathologies. The purpose of this study was to evaluate the contents of total phenolics, flavonoids, and caffeine in six medicinal plants used traditionally in phytotherapy, usually consumed as tea or infusion namely: Camellia sinensis, Melissa officinalis, Lippia citriodora, Cymbopogon citratus, Matricaria chamomilla, and Tilia cordata. Significant variations in total phenolics and flavonoids content were found among analyzed plants and depending on the nature of the extract. The concentration of caffeine was also very dissimilar and followed the sequence M. officinalis < T. cordata < C. citratus < M. chamomilla < L. citriodora < C. sinensis. Also, the antioxidant activity of each plant was found to vary according to C. citratus (90.9%) > C. sinensis (87.8%) > M. officinalis (50.7%) > M. chamomilla (45.3%) > T. cordata (32.2%) > L. citriodora (28.0%).