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Cardoso Freitas Lopes de Freitas, Ana Cristina
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- Impact of enzyme- and ultrasound-assisted extraction methods on biological properties of red, brown, and green seaweeds from the Central West Coast of PortugalPublication . Rodrigues, Dina; Sousa, Sérgio; Silva, Aline; Amorim, Manuela; Pereira, Leonel; Rocha-Santos, Teresa A.P.; Gomes, Ana M. P.; Duarte, Armando C.; Freitas, Ana CristinaSeaweeds are an excellent source of bioactive compounds, and therefore the use of sustainable and food compatible extraction methods such as enzyme-assisted (EAE) and ultrasound-assisted extraction were applied on Sargassum muticum, Osmundea pinnatifida, and Codium tomentosum. Extracts were evaluated for proximate characterization and biological properties. Higher extraction yields were observed for C. tomentosum EAE (48-62%; p < 0.05 for Cellulase and Viscozyme), followed by O. pinnatifida (49-55%; p < 0.05 except Alcalase) and S. muticum (26-31%; p < 0.05). S. muticum extracts presented the highest nitrogen (25 +/- 2 mg/g(lyoph) (extract)) and total phenolics (261 +/- 37 mu g(catechol) (equiv)/gl(yoph) (extract)) contents, whereas higher sugars (78 +/- 14 mg(glucose) (equiv)/g(lyoph) (extract)) including sulfated polysaccharide (44 +/- 8 mg(Na2SO4) (acid)/g(lyoph) (extract)) contents characterized O. pinnatifida extracts. A higher effect on hydroxyl-radical scavenging activity (35-50%) was observed for all extracts, whereas S. muticum Alcalase and C. tomentosum Cellulase extracts exhibited higher prebiotic activity than fructooligosaccharides. O. pinnatifida and C. tomentosum EAE showed inhibitory potential against alpha-glucosidase (38-49%).
- Uncovering Akkermansia muciniphila resilience or susceptibility to different temperatures, atmospheres and gastrointestinal conditionsPublication . Machado, Daniela; Almeida, Diana; Seabra, Catarina L.; Andrade, José Carlos; Gomes, Ana Maria; Freitas, Ana CristinaData regarding Akkermansia muciniphila viability under stress remains scarce despite its beneficial potential. Therefore, the main goal was to assess A. muciniphila culturability when exposed to different temperatures, atmospheres and gastrointestinal simulated conditions. Cultivable cell numbers A. muciniphila remain high after refrigerated and room temperatures oxygen exposure, and gastrointestinal passage.
- Dataset of the preparation and characterization of an artificial sludge for ecotoxicological purposesPublication . Gavina, Ana; Freitas, Ana Cristina; Ricardo, Amadeu; Gomes, Ana; Marques, Catarina; Lopes, Isabel; Pereira, RuthThis work describes the protocol developed for preparing an artificial digested sludge to be used for the ecotoxicological evaluation and risk assessment of chemical substances that are previewed to attain the soil through sewage sludge applications for fertilization (e.g. pharmaceutical compounds). Such evaluations have been made with standard protocols for ecotoxicological tests with terrestrial species in which the chemical substances are directly spiked to the test soil. This procedure lacks ecological relevance in terms of the role the sludge organic matter plays on the bioavailability and fate of chemical substances. Here we describe the protocol and the composition for obtaining the artificial sludge, prepared with commercial pet food and eggs white to mimic the composition of domestic sewage sludge in terms of proteins, carbon hydrates, fat and fibers content. Further, the conditions ascertained for the anaerobic digestion of the organic mixture are described, and the final properties of the sludge are presented, after repeating the procedure twice.
- A simplified strategy to measure glucose release in cooked rice samplesPublication . Rodrigues, Dina; Pimenta, Ana; Vasconcelos, Marta; Freitas, Ana Cristina; Gomes, Ana Maria
- Valorization of mushroom by-products as a source of value-added compounds and potential applicationsPublication . Antunes, Filipa; Marçal, Sara; Oludemi, Taofiq; Morais, Alcina M. M. B.; Freitas, Ana Cristina; Ferreira, Isabel C. F. R.; Pintado, ManuelaNowadays, the food sector is highly concerned with environmental issues and foreseen to develop strategies to reduce waste and losses resulting from activities developed in the food system. An approach is to increment added value to the agro-industrial wastes, which might provide economic growth and environmental protection, contributing to a circular economy. Mushroom by-products represent a disposal problem, but they are also promising sources of important compounds, which may be used due to their functional and nutritional properties. Research has been developed in diferent fields to obtain value added solutions for the by-products generated during mushroom production and processing. Bioactive compounds have been obtained and applied in the development of nutraceutical and pharmaceutical formulations. Additionally, other applications have been explored and include animal feed, fertilizer, bioremediation, energy production, bio-based materials, cosmetics and cosmeceuticals. The main purpose of this review is to highlight the relevant composition of mushroom by-products and discuss their potential as a source of functional compounds and other applications. Future research needs to explore pilot and industrial scale extraction methods to understand the technological feasibility and the economic sustainability of the bioactive compounds extraction and valorization towards diferent applications.
- Analytical approaches for proteomics and lipidomics of arsenic in algaePublication . Freitas, Ana Cristina; Gomes, Ana MariaArsenic (As) is an element with a complex chemistry found in relatively high concentrations in the marine environment. A diverse group of As compounds or As species exist in the marine environment and these are of importance to human health given their potential cytotoxicity. It has been pointed out that marine algae are the origin of such As compounds, since they accumulate arsenate from seawater and metabolize it into several organoarsenic species of both lipophilic and hydrophilic nature. In this chapter, it is intended to discuss lipidomics approaches for identification of the > 70 existing lipophilic arsenic species (arsenolipids) in algae which include arsenic incorporated into phospholipids, hydrocarbons, long-chain alcohols, and polyunsaturated fatty acids. In turn, proteomic analysis will also be presented and discussed in its role, for example, to investigate whether cells show a specific response or survival strategy when under arsenic-induced stress. Research on proteome involvement in stress and tolerance to arsenic offers new tools to understand the associated physiological and biochemical mechanisms connected with different algae responses. Protein biomarkers are also of interest to enable indication of quantitative changes in some physiological parameters as the result of stress or toxicity.
- Development of a rice-based fermented probiotic beverage with lactobacillus spp. and streptococcus thermophilusPublication . Gomes, Ana Maria; Ramalhosa, Francisco; Sousa, Sérgio; Rodrigues, Dina; Freitas, Ana Cristina
- Health benefits and bioavailability of marine resources components that contribute to health – what’s new?Publication . Nova, Paulo; Pimenta-Martins, Ana; Silva, Joana Laranjeira; Silva, Ana Machado; Gomes, Ana Maria; Freitas, Ana CristinaThe strict connection between nutritional intake and health leads to a necessity of understanding the beneficial and protective role of healthy nutrients and foods. The marine environment is a source of a plethora of many organisms with unique properties, extremely rich in bioactive compounds and with remarkable potential for medical, industrial and biotechnological applications. Marine organisms are an extreme valuable source of functional ingredients such as polysaccharides, vitamins, minerals, pigments, enzymes, proteins and peptides, polyunsaturated fatty acids (PUFA), phenolic compounds and other secondary metabolites that prevent or have the potential to treat several diseases given their cardiovascular protective, anti-inflammatory, anti-hypertensive, anti-oxidant, anti-coagulant, anti-proliferative and anti-diabetic activities. This review provides an overview on the current advances regarding health benefits of marine bioactive compounds on several diseases and on human gut microbiota. In addition, it is discussed a crucial factor that is related to the effectiveness of these compounds on human organism namely its real bioavailability.
- Akkermansia muciniphila robustness towards different temperatures, atmospheres and gastrointestinal conditionsPublication . Freitas, Ana Cristina; Machado, Daniela; Almeida, Diana; Seabra, Catarina; Andrade, José Carlos; Gomes, Ana Maria
- Commensal obligate anaerobic bacteria and health: production, storage, and delivery strategiesPublication . Andrade, José Carlos; Almeida, Diana; Domingos, Melany; Seabra, Catarina Leal; Machado, Daniela; Freitas, Ana Cristina; Gomes, Ana MariaIn the last years several human commensals have emerged from the gut microbiota studies as potential probiotics or therapeutic agents. Strains of human gut inhabitants such as Akkermansia, Bacteroides, or Faecalibacterium have shown several interesting bioactivities and are thus currently being considered as food supplements or as live biotherapeutics, as is already the case with other human commensals such as bifidobacteria. The large-scale use of these bacteria will pose many challenges and drawbacks mainly because they are quite sensitive to oxygen and/or very difficult to cultivate. This review highlights the properties of some of the most promising human commensals bacteria and summarizes the most up-to-date knowledge on their potential health effects. A comprehensive outlook on the potential strategies currently employed and/or available to produce, stabilize, and deliver these microorganisms is also presented.
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