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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.
- 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.
- 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
- Design of a lipid nanovesicle system encapsulating bacteriophages integrated in a multiple emulsion formulation: A proof-of-conceptPublication . Balcão, V. M.; Azevedo, A.F.; Castro, L.M.; Costa, Carla Isabel; Santos, S. R. B.; Matos, C. M.; Moutinho, C. G.; Teixeira, J. A.Development of a biotechnological process for the inhalational administration of a bacteriophage was pursued, using strategies of nanoencapsulation within lipid nanovesicles. As a proof-of-concept for the nanoencapsulation strategy, a bacteriophage with broad lytic spectrum was entrapped within W/O/W multiple nanoemulsions. Physicochemical characterization of the optimized bacteriophage-encasing nanovesicles encompassed determination of particle hydrodynamic size, size distribution and particle charge via DLS, surface morphology via CRYO-SEM, and thermal analysis via DSC, whereas antimicrobial activity of the nanoemulsions produced was assessed in vitro using several bacterial strains. The optimized nanosystems showed no phase separation and encompassed nanovesicles with an average size of ca. 114 nm and an average Zeta Potential of ca. -13 mV, which were maintained stable over a storage timeframe of ca. 3 months.
- Liposomes as a Model for the Biological Membrane: Studies on Daunorubicin Bilayer InteractionPublication . Matos, Carla; Moutinho, Carla; Lobão, PauloIn this study the interaction of the antitumoral drug daunorubicin with egg phosphatidylcholine (EPC) liposomes, used as a cell membrane model, was quantified by determination of the partition coefficient (K(p)). The liposome/aqueous-phase K(p) of daunorubicin was determined by derivative spectrophotometry and measurement of the zeta-potential. Mathematical models were used to fit the experimental data, enabling determination of K(p). In the partition of daunorubicin within the membrane both superficial electrostatic and inner hydrophobic interactions seem to be involved. The results are affected by the two types of interaction since spectrophotometry measures mainly hydrophobic interactions, while zeta-potential is affected by both interpenetration of amphiphilic charged molecules in the bilayer and superficial electrostatic interaction. Moreover, the degree of the partition of daunorubicin with the membrane changes with the drug concentration, due mainly to saturation factors. Derivative spectrophotometry and zeta-potential variation results, together with the broad range of concentrations studied, revealed the different types of interactions involved. The mathematical formalism applied also allowed quantification of the number of lipid molecules associated with one drug molecule.
- Invasive plants and their possible applications - phytochemical profile and biological properties: a reviewPublication . Ferreira da Vinha, Ana; Silva, Carla Sousa e; Moutinho, Carla; Matos, CarlaInvasive species are distinguished by their simplicity in reproductive and ability to adapt to adverse environments. Biological invasion has been identified as the primary driver of global change, responsible for biotic interchange and, as a result, habitat homogenization. It is well recognized that invasive species have been one of the primary causes of native species loss in recent centuries, affecting the natural ecosystem of each geographic area. Furthermore, the number of invasive species is fast increasing in all countries and taxonomic groupings, thus it is critical to implement more effective measures than those that have been used, which may include their phytochemical evaluation and, biological activities for future applications in phytotherapy and pharmacy. This review intends to show the phytochemical potential of three known invasive species, commonly present in the Portuguese maritime coastal zones, specifically, Agave americana, Carpobrotus edulis and Arundo donax. This study can be extended to other similar situations involving invasive species from other countries with the goal to enhance the efficiency of potential future projections for these species, particularly on the phytotherapeutic and pharmaceutical levels. Technological and scientific comprehension of these species' chemical and biological qualities will serve improve the efficiency of the management strategies will be implemented, emphasizing a sustainable economy.
- 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.