Bioaccessibility of minerals in combinations of biofortified foods with Fe, Zn and vitamin A.

Initiatives to improve the nutritional quality of staple foods, such as beans and cassava by bio fortification should be encouraged as an alternative to overcome the deficiencies of iron and vitamin A. The evaluation of the bio accessibility of the minerals in these foods is also important, since the composition of nutrients does not necessarily correspond to the amount absorbed and metabolized in the body. Thus, the present work aims to evaluate the bio accessibility of iron (Fe) and zinc (Zn) in the presence of ß-carotene in combinations of bio fortified food sources of Fe and Zn (cowpea cooked with and without maceration: CM/CW, respectively) and ß-carotene (cooked cassava and cassava flour: CC/CF, respectively). The mixtures, after cooking, were analyzed for the centesimal composition and minerals, phytates, the percentage of iron and zinc bio accessibility by in vitro method and molar ratio. The mixtures presented significant amounts of proteins, carbohydrates and fibers. The ß-carotene content showed no statistical difference in processing methods. The Fe content showed lower levels in the controls with cassava flour and its bio accessibility was also lower for treatment with cassava flour with CM, while for Zn or higher content it was used for treatment CW/CF, differing only from the treatment CW/CC, although their bio accessibilities were not different, except to iron in CMCC treatment. Both the IP6 fraction and the IP5 fraction did not show a significant difference (p > 0.05) between the treatments, it suggests no interference in bio accessibility. A diet rich in iron and vitamin A in adequate amounts with minimal content of absorption inhibitors can be effective in controlling iron deficiency. Bio fortified mixtures must be encouraged in different forms of consumption.

Cultivars of biofortified cowpea and sweet potato: Bioavailability of iron and interaction with vitamin A in vivo and in vitro.

The objective of this study was to evaluate the interaction of pro-vitamin A-rich sweet potato on iron bioavailability of biofortified cowpeas, using in vitro Caco-2 cells and in vivo depletion-repletion rat model. Mixtures of conventional rice with cultivars of iron-biofortified (Aracê, Xiquexique, and Tumucumaque) or conventional (Guariba) cowpeas with or without sweet potato biofortified with pro-vitamin A carotenoids were evaluated. The ratio of ferritin/total protein in Caco-2 cells was used as the index of cellular Fe uptake in the in vitro assay. The animal study evaluated the hemoglobin gain, the relative biological value, and the gene expression of transferrin and ferritin proteins by reverse transcription polymerase chain reaction. In the in vitro study, Xiquexique cowpea presented higher bioavailability of iron in the absence of sweet potato, and no difference was observed between the other cultivars of cowpea with and without sweet potato. The in vivo bioavailability (relative biological value of hemoglobin regeneration efficiency) differed statistically only between Guariba groups added to sweet potato and Tumucumaque. Ferritin mRNA expression did not differ between the test and control (ferrous sulfate) groups. Regarding the transferrin mRNA expression, there was a difference between the test and control groups except for the Xiquexique group. The association of rice and beans with sweet potato rich in carotenoids favored the gene expression of proteins involved in the iron metabolism, as well as its bioavailability, corroborating beneficial effects of this mixture. Xiquexique cowpea was shown to be the most promising compared to the other cultivars, exhibiting higher iron content in the digestible fraction, better in vitro bioavailability of iron, and transferrin gene expression. PRACTICAL APPLICATION: Data from the study indicated greater in vitro bioavailability of iron for Xiquexique cowpea and sweet potato mixtures, in addition to the greater regeneration efficiency of hemoglobin in vivo as the bioavailability of iron among biofortified beans, highlighting the promising benefits of biofortification.

Fe and Zn in vitro bioavailability in relation to antinutritional factors in biofortified beans subjected to different processes.

The present work evaluated the effect of different processes in relation to mineral content and its bioavailability, as well as the effect of phytate and oxalate contents in biofortified beans. The following treatments were evaluated: raw beans (RB), cooked and oven-dried soaked beans (BOS), cooked and freeze-dried soaked beans (BFS), cooked and oven-dried beans without soaking (BOWS) and cooked and freeze-dried beans without soaking (BFWS). The mineral contents (mg per 100 g) varied between 3.56 and 5.80 (iron), 20.26 and 89.32 (calcium) and 1.56 and 2.38 (zinc). The oxalate content varied from 3.74 to 10.54 mg per 100 g. The total phytate content ranged from 1803.23 to 2.301 mg per 100 g. Regarding mineral bioavailability in Caco-2 cells, iron retention ranged from 8.89 to 17.85% and uptake was from 12.07 to 13.74 µg. On the other hand, the zinc retention was from 92.27 to 98.6% and uptake ranged from 24.68 to 36.26 µg. The different forms of bean processing can contribute to the mineral profile of this legume, in addition to increasing the bioavailability of some minerals, such as iron and zinc.

Effect of thermal processing and maceration on the antioxidant activity of white beans.

Phenolic compounds, which naturally occur in beans, are known to have antioxidant activity, which may be partially lost during the processing of this legume. This study evaluated the effect of thermal processing and maceration on the phenolic acid and flavonoids profile and content and on the antioxidant activity of white beans. According to the results obtained from the 2,2-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) method, there were no significant differences among treatment groups analysed. When was using 1,1-diphenyl-2-pycrylhydrazyl method (DPPH), beans cooked without maceration present the higher antioxidant activity, and raw beans the lower. The phenolic acids found in greater amounts were gallic acid and chlorogenic acid. Kaempferol was only detected in the soaked and cooked samples; catechin and kaempferol-3-rutinoside were found in the highest concentrations. Quercetin and kaempferol-3-glucoside were not affected by the cooking process, either with or without maceration. In general, the heat treatment increased the antioxidant activity.

Iron bioavailability of common beans (Phaseolus vulgaris L.) intrinsically labeled with (59)Fe.

A radiobioassay was performed in rats with or without iron depletion to evaluate the iron bioavailability of diets enriched with common beans and with "multimixture", a nutritional supplement based on parts of foods that are not usually eaten. The full-body (59)Fe level was determined after 5h, the absorbed (59)Fe level was determined after 48 h, and the amount of (59)Fe retained was determined after 7 days. Iron bioavailability was assessed by the full-body radioactivity of the animals, determined using a solid scintillation detector. The iron bioavailability of common beans was higher in the iron-depleted animals (55.7%) than in the non-depleted animals (25.12%) because of the higher absorption rate in the iron-depleted animals. The multimixture did not influence dietary iron bioavailability. In addition, the iron bioavailability of common beans was similar to that observed in the standard source of iron for Wistar rats. Hence, common beans may be considered an adequate dietary iron source because of its high bioavailability.

Métodos de determinação da biodisponibilidade do ferro: ênfase na utilização de radionuclídeo 59 / Methods for determining the bioavailability of iron: emphasis on the use of 59

Iron deficiency can be caused by imbalance between the available amount of the mineral and the body requirement. Thus, the study of iron bioavailability has been of growing interest from the nutritional point of view, due to its recognized role in the physiological and biochemical regulation, besides the contribution to the establishment of recommendations for intake of this element depending on the individuals? requirements and disease prevention. In the assessment of bioavailability, one should use methodologies depicting the chemical forms, allowing for a thorough ana lysis of the results and repeating the physiological conditions as much as possible. Therefore, radioisotopes are ideal tracers due to the specifi city of their identifi cation and quantification. This procedure is usually characterized by good precision, due to the greater analytical sensitivity and the ability for detection ?in vivo?. This work aims to elucidate the use of radioisotopes in various methodologies for studies of iron bioavailability in animals.

La anemia por deficiencia de hierro puede ser causada por desequilibrio en la cantidad biodisponible y su necesidad orgánica. Debidoa eso, la biodisponibilidad de hierro ha sido objeto de creciente interés desde el punto de vista nutricional por el reconocido papel en laregulación fisiológica y bioquímica, además de contribuir a la fijación de la ingestión recomendada de este elemento en función de las necesidades de los individuos y para prevenir enfermedades. En la evaluación dela biodisponibilidad deberán ser utilizadas metodologías que procuren dilucidar las formas químicas, que permitan un análisis cuidadosode los resultados y que reproduzcan lo más fielmente posible las condiciones fisiológicas. Por eso, los radioisótopos trazadores son ideales,por la especificidad con que son identificados y cuantificados. Este trabajo tuvo por objetivo dilucidar la utilización de radioisótopos en diversas metodologías para estudios de biodisponibilidad de hierro en animales.

A anemia ferropriva pode ser causada pelo desequilíbrio na quantidade biodisponível e a sua necessidade orgânica. Assim, o estudode biodisponibilidade do ferro tem sido alvo de crescente interesse do ponto de vista nutricional, pelo reconhecido papel na regulaçãofisiológica e bioquímica, além de contribuir no estabelecimento das recomendações de ingestão deste elemento em função das necessidades dos indivíduos e para prevenir doenças. Na avaliação da biodisponibilidade, deverão ser utilizadas metodologias que procurem elucidar as formas químicas, que permitam uma análise criteriosados resultados e que reproduzam o mais possível as condições fisiológicas. Assim, os radioisótopos são traçadores ideais pela especificidade com que são identificados e quantificados. Esseprocedimento é normalmente caracterizado por boa precisão, devido à maior sensibilidade analítica e à capacidade de detecção in vivo. Opresente trabalho objetiva elucidar a utilização dos radioisótopos em diversas metodologias para estudos de biodisponibilidade de ferro emanimais.

Bioavailability of iron in the regional basic diet (RBD) with dietary supplement in Brazil.

The consumption of the regional basic diet (RBD) determines a state of malnutrition found in the low-income population of Northeastern Brazil. A dietary supplement known as multimixture has been used as an alternative source of iron in food for the prevention and/or treatment of anemia and for the recovery from malnutrition. The purpose of the present work was to evaluate the bioavailability of iron in the RBD supplemented with multimixture in iron-depleted and non-depleted Wistar rats. To produce iron depletion in the animals, pretest depletion diets without iron and the pretest control diet based on the AIN-93 diet were used for 8 weeks. This phase was followed by the test diets: control, AIN-93 extrinsically labeled with (59)FeCl(3); RBD, containing carioca beans intrinsically labeled with (59)Fe; and RBDMM, RBD plus multimixture, supplied in a single meal. Hemoglobin concentration, weight gain, and dietary intake were determined in the pretest phase. Iron bioavailability was determined by the determination of total-body radiation in the animals for 7 days, using a solid scintillation detector. The hemoglobin concentration, weight gain, and dietary intake were greater in the non-depleted animals than in the iron-depleted ones. The iron bioavailability of the diets did not differ significantly. It was concluded that the multimixture did not affect the bioavailability of Fe contained in the beans of the RBD.