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| Author(s): |
André Luiz Tognon
Total Authors: 1
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| Document type: | Master's Dissertation |
| Press: | São Carlos. |
| Institution: | Universidade de São Paulo (USP). Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto (PCARP/BC) |
| Defense date: | 2012-04-20 |
| Examining board members: |
Márcia Andreia Mesquita Silva da Veiga;
Delia Rita Tapia Blácido;
Joaquim de Araujo Nobrega
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| Advisor: | Márcia Andreia Mesquita Silva da Veiga |
| Abstract | |
The micro and macroelements are essential nutrients for proper functioning of the human metabolism, directly or indirectly participating in various metabolic functions and structural organization, such as cofactors of enzymes, osmotic equilibrium at the interface of biological membranes, biosignaling, important constituents of biomolecules for body, among others. The consumption of fruits, vegetables and cereals in the diet is a way to obtain the daily requirements of these nutrients, since it is a group of foods rich in these elements. Taking into account that only a portion of the nutrients of a food is bioaccessible during human digestion, assess the bioaccessibility these nutrients is very important. This research aimed to quantify, by means of atomic absorption spectrometric techniques, the micro and macroelements content in foods within of group of fruits, vegetables and cereals (more or less known by Brazilian population in general), and subsequently evaluating, by means of an in vitro test, the bioaccessibility these elements in the food. Furthermore, in order to seek correlations between the results, the percent composition and phytic acid content of foods analyzed were also determined. The percent composition of food revealed that the pseudocereals amaranth and quinoa are important sources of protein for humans. With regard to cereals, it became clear that the cooking process causes a decrease in the total contents of micro and macroelements determined in the research, but also makes the percentages of bioaccessibility increase considerably compared to raw grains, showing that the more nutritional potential of cereals analyzed (in relation to micro and macroelements studied) is obtained when the cereals are cooked. The total and bioaccessibles amounts of elements in foods allowed to observe that there is a relationship between the amount of a chemical element necessary in the daily diet of humans, and the amount of that element present in fruits, vegetables and cereals analyzed in the research, because for the macroelements these quantities (total and bioaccessible) were generally larger than those corresponding to the microelements. Furthermore, the results showed that the vegetables analyzed can act as good sources of calcium (Ca) for the daily diet of humans, and that the macroelement potassium (K) has the largest totals and bioaccessibles quantity, information that is in accordance with the fact of the K be essential in the growth of any plant species, and that all foods analyzed in this research are derived directly or indirectly from plant species. Overall it was observed that the amount bioaccessible of elements in the food less known is equal or greater in relation to the corresponding quantities present in the foods well known by Brazilian population, demonstrating the nutritive potential of fruits, vegetable and cereals less known analyzed. The determination of content of phytic acid (phytates) of foods allowed to evidence the trend of that as higher the phytic acid content of a food, lower the percentage of bioaccessibility mineral (micro and macroelements). For cereals was observed some contradictions to this trend, which allowed to conclude that the influence of phytic acid (and their phytates) in the bioaccessibility mineral depends of part of cereal grains (pericarp, endosperm and germ) that contains the largest percentages of total content of phytic acid and of chemical elements nutrients. Furthermore, the results also showed that the phytate have different intensities of connection with the cations of nutrients elements present in food samples; thus the influence of phytic acid in bioaccessibility is greater for some elements and smaller for other, depending on stability of mineral-phytate complexes. Comparing type by type the foods less and well known by Brazilian population in general, it was found that even with phytic acid content comparable to the most popular foods, in less known foods this content has a minor influence on the mineral bioaccessibility in general, showing that the foods less known studied have a nutritional value in relation to micro and macroelements comparable and, in some cases, greater than the well known foods. Taking into account that the phytic acid (and their phytates) can also bring health benefits, the results showed that amaranth and quinoa are foods with remarkable nutritional properties, since they combine a significant content of phytic acid with good bioaccessibles amounts of micro and macroelements determined in the research. (AU) | |
| FAPESP's process: | 09/12061-9 - Quantification and assessment of in vitro bioacessibility of micro and macroelements in fruits, vegetables and cereals. |
| Grantee: | André Luiz Tognon |
| Support Opportunities: | Scholarships in Brazil - Master |