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- Nutraceuticals based on portuguese grape pomaces as a potential additive in food productsPublication . Ferreira da Vinha, Ana; Silva, Carla Sousa e; Sousa, Gonçalo de Magalhães e; Moutinho, Carla; Brenha, João; Sampaio, RicardoPortuguese wine industry by-products are often undervalued but constitute a potential source of bioactive phenoliccompounds that can be applied as a natural additive in several industries. In this context, the present study aimed to evaluate the nutritional composition, and the phenolic profile of two Portuguese Vitis vinifera L. grape pomaces (Touriga Nacional (red variety) and Alvarinho (white variety), and to correlate their chemical characterizations with their antioxidant activities. Strong correlations were observed between the presence of phenolic compounds and antioxidant activities, which enhances the application of pomace extracts in food and pharmaceutical areas. The high content of total phenolic compounds (25 - 41 g/ kg dry extract) and of flavonoids (9.2 - 18 g/ kg dry extract) found in both samples make these pomaces excellent candidates as food additives in food products, as well as antioxidant agents, such as natural dyes. Some polyphenols were identified by High Performance Liquid Chromatography (HPLC), being rutin and catequin the highest compounds found in red grape pomace (Touriga Nacional) while quercetin was only quantified in white grape pomace (Alvarinho). Cis-resveratrol was quantified in both grape pomace, which opens horizons for its use since this compound has considerable chemopreventive effects in the three main gains of carcinogenesis. As expected, the anthocyanin content was significantly higher in red grape pomace (37 g/ kg dry extract), emphasizing its interest as a natural food additive. Based on the findings, it is possible to conclude that these by-products have additional value, making them potentially useful in the food, pharmaceutical, and cosmetic industries.
- High-value compounds in papaya by-products (Carica papaya L. var. Formosa and Aliança): potential sustainable use and exploitationPublication . Ferreira da Vinha, Ana; S.G.Costa, Anabela; Espírito Santo, Liliana; Ferreira, Diana Melo; Silva, Carla Sousa e; Pinto, E.; Almeida, Agostinho; Oliveira, M. Beatriz P.P.Background: Food waste is a global and growing problem that is gaining traction due to its environmental, ethical, social, and economic repercussions. Between 2022 and 2027, the worldwide papaya market is expected to have a huge increase, meaning a growth in organic waste, including peels and seeds. Thus, this study evaluated the potential use of peels and seeds of two mature papaya fruits as a source of bioactive compounds, converting these by-products into value-added products. Proximate analysis (AOAC methods), mineral content (ICP-MS), free sugars (HPLC-ELSD), fatty acid composition (GC-FID), vitamin E profile (HPLC-DAD-FLD), and antioxidant activity (DPPH and FRAP assays) were evaluated. Results: Both by-products showed high total protein (20–27%), and dietary fiber (32–38%) contents. Papaya peels presented a high ash content (14–16%), indicating a potential application as a mineral source. 14 fatty acids were detected, with α-linolenic acid (30%) as the most abundant in the peels and oleic acid (74%) in the seeds. Both by-products showed high antioxidant activity. Conclusion: Papaya by-products display great potential for industrial recovery and application, such as formulation of new functional food ingredients.
- Edible flowers of ornamental plants: a food promise in the sustainability sectorPublication . Pinto, Sara; Oliveira, Adriana; Silva, Carla Sousa e; Ferreira da Vinha, AnaThe growing interest in nutraceutical ingredients and functional foods has increased research into new foods that provide beneficial health. Although flowers were already used as food in ancient times, they have only recently sparked off nutraceutical research focusing on new agronomic and economic horizons, which are part of the concept of sustainability. OBJECTIVES: Having in mind the potential of edible flowers as source of bioactive compounds and related antioxidant activity, this work evaluated the contents of total phenolics and flavonoids, in aqueous extracts of rose (Rosa canina L.), marigold (Calendula officinalis L.) and camellia (Camellia L.). Additionally, the antioxidant activity of all the extracts was evaluated.
- 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.
- Antioxidant activity of the garlic (Allium sativum L.) submitted to different technological processesPublication . Silva, Carla Sousa e; Novo, Catarina; Ferreira da vinha, Ana
- 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.
- Variation in chemical composition and antioxidant activity of fresh tomato fruit: combined effect of cultivar and storagePublication . Ferreira da Vinha, Ana; Silva, Carla Sousa e; Castro, Ana; Soares, Marta De Oliveira; Oliveira, M. Beatriz P.P.; Costa, A.S.G.Tomato (Lycopersicon esculentum Mill.) is one of the most consumed vegetables in the world and probably the most preferred garden crop. It is a key component of the Mediterranean diet, commonly associated with a reduced risk of chronic degenerative diseases. Currently there are a large number of tomato cultivars with different morphological and sensorial characteristics. Its consumption brings health benefits, linked with its high levels of bioactive ingredients, including carotenoids such as β-carotene, a precursor of vitamin A, and mostly lycopene, which is responsible for the red colour, vitamins in particular ascorbic acid and tocopherols, phenolic compounds including hydroxycinnamic acid derivatives and flavonoids, and lectins. The content of these compounds is variety dependent. Besides, unlike unripe tomatoes, which contain a high content of tomatine (glycoalkaloid) but no lycopene, ripe red tomatoes contain high amounts of lycopene and a lower quantity of glycoalkaloids. Current studies demonstrate the several benefits of these bioactive compounds, either isolated or in combined extracts, namely anticarcinogenic, cardioprotective and hepatoprotective effects among other health benefits, mainly due to its antioxidant and anti-inflammatory properties. This study intended to evaluate the influence of different postharvest cooling conditions in the chemical composition, antioxidant activity and microbiological contamination of tomato cultivars namely: Cereja, Chucha, Rama and Redondo. Pink fruits were kept for 15 days under three different storage temperatures (6ºC, 12ºC and 25ºC) during which their lycopene, ascorbic acid contents, total phenolics and antioxidant activity were evaluated every three days. Counts of colony forming units of coliform bacteria, yeasts and molds and the presence of Escherichia coli, were determined before and after 15 days of storage. All studied parameters revealed that temperature and storage duration caused statistically significant differences in nutritional values of every cultivar. It was observed an increase in the lycopene concentration and antioxidant activity with temperature and storage duration. The phenolic and ascorbic acid contents showed a slight increase during storage at every temperature. Microbial contamination was only found in cultivars that grew in direct contact with the soil (Chucha and Redondo) and bacterial population increased exponentially with storage temperature. Our results indicate that the ideal temperature to maintain optimal physiological, biochemical and microbiological profiles of the cultivars studied is 12ºC and that the cv. Rama fruit is the most suited for consumption in natura.
- Flores edíveis como recurso natural de compostos bioativos e propriedades biológicasPublication . Pinto, Sara Vanessa; Oliveira, Adriana; Silva, Carla Sousa e; Manso, M. Conceição; Ferreira da Vinha, AnaAtualmente, muitas espécies de plantas que produzem flores já fazem parte da alimentação humana, salientando-se em particular as pétalas e sépalas edíveis. Habituais na cozinha desde a Antiguidade, o uso das flores não tem sido usual em Portugal. No entanto, com as novas tendências de recuperar os sabores agridoces e das múltiplas variantes da cozinha de fusão, as flores tornam-se ingredientes muito apreciados. Nem todas as flores são comestíveis. Para além da identificação das mesmas, é importante saber como foram produzidas pois, por exemplo, as flores para decoração ornamental não devem ser utilizadas para consumo humano, uma vez que não têm em consideração as regras de segurança alimentar. Contudo, existe pouca informação sobre algumas espécies de flores destinadas a consumo humano, nomeadamente calêndula (Calendula officinalis L.), camélia (Camellia japonica L.) e rosa (Rosa canina L.). Nesse sentido, o presente trabalho pretendeu contribuir para aumentar o conhecimento neste tema, designadamente ao nível da caracterização química e das propriedades antioxidantes destas espécies botânicas. Embora as três espécies de flores estudadas tenham compostos bioativos e atividade antioxidante, a C. officinalis foi a que apresentou o maior teor em fenólicos totais e carotenoides e, consequentemente, maior atividade antioxidante.
- Phytotherapeutic activities of six plant infusions: chemical constituents and antioxidant activityPublication . Ferreira da Vinha, Ana; Silva, Carla Sousa eThe use of traditional medicine is attributable not only to cultural and poverty reasons but also to the ineffectiveness of many existing medicines. 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. In addition, they can prevent oxidative modification by neutralizing free radicals, oxygen scavenging, or decomposing peroxides through their antioxidant activities. 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.
- 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%).