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- Total antioxidant activity and trace elements in human milk: the first 4 months of breast-feedingPublication . Matos, Carla; Moutinho, Carla; Balcão, Victor; Almeida, Cristina; Ribeiro, Marta; Marques, Agostinho Franklim; Guerra, AntónioThe content of many nutrients in breast milk are dependent on the nutritional status of the lactating woman. This is particularly true for fat and water-soluble vitamins, some of which have antioxidant properties. The aim of the study entertained herein was to evaluate the changes in total antioxidant status of human milk during the first 4 months of lactation, and to correlate such changes with the contents in specific antioxidant oligoelements (Cu, Zn, Mn and Se). Milk samples were collected from (31) lactating women recruited at the Service of Obstetrics of the Hospital de São João in Porto, after 1, 4, 8, 12 and 16 weeks after birth. The total antioxidant status (TAS) of human milk was measured by the Randox® commercial kit and trace metals by ICP-MS (inductively coupled plasma-mass spectrometry). The results found for TAS and oligoelements under study show a decrease in the concentration of these parameters from 7 days to 4 months of breast-feeding and significant correlations (p < 0.05) were found between TAS and Cu, Zn and Se (not Mn). The decreases of Cu, Zn and Se were also correlated, but not proportional between them, suggesting diverse excretion mechanisms for all. Between primipara and multipara women, a significant difference was found only for Cu and Zn concentrations at 7 days of lactation, but not for the other metals or TAS. With respect to the mother’s age, no correlation was found, either for trace metal concentrations or TAS.
- Fatty Acid Profile of Human Milk of Portuguese Lactating Women: Prospective Study from the 1st to the 16th Week of LactationPublication . Ribeiro, M.; Balcão, Victor; Guimaraes, H.; Rocha, G.; Moutinho, Carla; Matos, Carla; Almeida, Cristina; Casal, S.; Guerra, A.Background/Aims: Fatty acid (FA) composition varies over the course of the day and during lactation. The aim of this study was to evaluate FA composition and its compositional stability in human milk, from day 7 to week 16 of lactation. Methods: Human milk was collected from all feedings over 24 h at day 7 and weeks 4, 8, 12 and 16 of lactation in 31 lactating women. FAs were analyzed through gas chromatography. Comparisons were made with analysis of variance. Results: Total monounsaturated FAs decreased from 33.04 ± 2.58% wt/wt at day 7 to 31.48 ± 3.32% wt/wt at week 16 of lactation, much at the expenses of the decrease in the major monounsaturated FA found in human milk, oleic acid. Main polyunsaturated FAs n-6 and n-3 showed fluctuations from day 7 up to week 16 of lactation, but with no statistical significance. Arachidonic acid significantly decreased from transitional to mature milk. Conclusions: The FA profile obtained throughout the study time points presented very low levels of oleic acid and very high linoleic acid/α-linoleic acid ratios which reflect recent changes in Portuguese women’s food patterns. Despite this, the ascorbate/dehydroascorbate ratio remained constant during the study, suggesting a protective metabolic mechanism.
- Proteins and peptides: non-invasive deliveryPublication . Balcão, Victor; Moutinho, Carla
- Nanoencapsulation of bovine lactoferrin for food and biopharmaceutical applicationsPublication . Balcão, Victor; Costa, Carla I.; Matos, Carla; Moutinho, Carla; Amorim, Manuela; Pintado, Manuela E.; Gomes, Ana P.; Vila, Marta M.; Teixeira, José A.Lactoferrin has for long captured the interest of many researchers as a natural compound with a wide variety of uses. Lactoferrin is a monomeric, iron-binding 80 kDa glycoprotein, and appears to be the subfraction of whey with the best documented antiviral, antimicrobial, anticancer and immune modulating/enhancing effects. It belongs to the family of transferrin proteins, and serves to control iron levels in body fluids by sequestering and solubilizing ferric iron. In the present research effort, production of lactoferrin derivatives (starting from a purified commercial extract), encompassing full stabilization of its three-dimensional structure, has been attempted via nanoencapsulation within lipid nanovesicles, integrating a multiple water-in-oil-in-water emulsion. Long-term storage of the multiple nanoemulsions produced did not lead to leaching of protein, thus proving the effectiveness of the encapsulation procedure. Furthermore, lactoferrin nanovesicle derivatives prepared under optimal conditions were successfully employed at lab-scale antimicrobial trials.
- 160 Fatty Acid Composition of Human Milk in a Portuguese Urban Population:Prospective Study from 7 Days to 16 Weeks of LactationPublication . Ribeiro, M; Balcão, Victor; Guimaraes, H; Rocha, G; Moutinho, Carla; Casal, S; Oliveira, B; Guerra, A
- Alimentos potenciadores de saúde: produtos lácteos probióticosPublication . Balcão, Victor; Moutinho, Carla; Matos, Carla; Almeida, CristinaOs alimentos probióticos em geral têm sido definidos como sendo “suplementos alimentares incorporando microorganismos vivos (bactérias probióticas) que afectam beneficamente o hospedeiro, melhorando o equilíbrio da sua microflora a nível intestinal”. O leite e os produtos lácteos em geral contêm vários biocomponentes que fornecem elementos nutritivos críticos e protecção imunológica, bem como substâncias biologicamente activas tanto a recém-nascidos como a adultos, pelo que estes alimentos pertencem ao grupo dos chamados alimentos funcionais. Produtos alimentares à base de leite inteiro ou lácteos fortificados ou enriquecidos podem, de facto, produzir efeitos potencialmente benéficos na melhoria da saúde humana e na prevenção de doenças, quando consumidos como parte de uma dieta variada e de forma regular.
- Flavour development via lipolysis of milkfats: changes in free fatty acid poolPublication . Regado, Mafalda A.; Cristóvão, Betina M.; Moutinho, Carla; Balcão, Victor M.; Aires-Barros, Raquel; Ferreira, João Paulo M.; Xavier Malcata, F.Under the trade name lipolysed milkfat (LMF), concentrated cheese flavours obtained via enzymatic treatments of cheese (or other dairy substrates) have been made available in increasing numbers. In this research effort, (anhydrous) milkfats from cows, ewes and goats were used as substrates for production of cheesy flavours. Those milkfats were subjected to modifications brought about by ten different (commercial) lipases and one cutinase, and the free fatty acids released were analysed by high performance liquid chromatography. Both the degrees of hydrolysis and the free fatty acid profiles of the final products were similar to those reported for several LMF products, although specific keynotes could be pinpointed. Consequently, those milkfats may represent alternative raw materials for manufacture of cheesy flavours, while contributing to alleviate the problem derived from the increasing surplus of milkfat in Western countries.
- Insights into protein-ionic liquid interactions aiming at macromolecule delivery systemsPublication . Harada, Liliam; Pereira, Jorge; Campos, Welida; Silva, Erica; Moutinho, Carla; Vila, Marta; Oliveira Jr., José; Teixeira, José; Balcão, Victor; Tubino, MatthieuOver the last few years, researchers have started to explore a particular class of compounds defined as ionic liquids (ILs) in attempts to use their unique characteristics. Since ILs have a very low vapor pressure, these fascinating compounds hold great potential as high performance chemicals for several applications in the (bio)pharmaceutical industry. In general, and unlike common organic solvents with comparable polarities, ILs are quite compatible with enzymes (enhancing their structural and chemical stability) and other proteins, since they can promote higher selectivities, faster reaction rates and greater enzyme stabilities in biocatalytic reactions providing, at the same time, a path for the structural and functional stabilization of protein entities. ILs appear to enhance the delivery of macromolecules, particularly protein entities, and their interactions with ILs will be tackled in detail in this review paper.
- Alimentos transgénicos: questões de biosegurançaPublication . Moutinho, Carla; Balcão, Victor; Matos, Carla; Almeida, CristinaAs técnicas de modificação genética (MG), suportadas pela tecnologia de DNA recombinante, encerram um tremendo potencial para oferecer melhorias muito significativas na quantidade, qualidade e aceitabilidade dos alimentos a nível mundial. Investigadores e técnicos e engenheiros alimentares podem apoiar a introdução responsável de técnicas de MG desde que sejam satisfatoriamente considerados problemas de segurança (alimentar) do produto, preocupações ambientais, informação ao consumidor e ética. Apenas desta forma se poderão traduzir os benefícios que a tecnologia de DNA recombinante pode trazer, quanto mais não seja para ajudar a alimentar a sempre em crescimento população mundial nas próximas décadas.
- Development of innovative nanotechnology-based drug delivery systems for cancer therapyPublication . Moutinho, Carla; Matos, Carla; Balcão, VictorControlled drug delivery systems are not a new subject in the biomedical field. The continuously increasing need for the improvement of health care services has been the driving force for both search and development of such systems. Among these, micro- and nano-sized vehicles (e.g. nanocapsules, liposomes and mixed micelles) have received special attention over the last decade; they have been used for the delivery and vectorization of many pharmacologically active molecules, as is the case of anti-neoplastic drugs.