In vitro determination of zinc dialyzability from duplicate hospital meals: influence of other nutrients

Total Zn of foods and bioaccesible fractions in the small and large intestine after in vitro digestion and fermentation with fecal material of healthy adults and children: Influence of culinary techniques

The healthy status of human beings is associated with an appropriate nutritional status in Zn, which must firstly be bioavailable. We measured the total Zn amount and its bioaccesibility in raw foods and after cooking by common culinary techniques. These foods were submitted to an in vitro digestion and fermentation with faecal inocula from healthy adults and children to evaluate Zn bioaccesibility in the small and large intestine. Mean total Zn amount provided by foods was 8.080 μg/g. Zn amount released from food in the small intestine was significantly different among several food groups and lower in raw vegetal foods compared to cooked ones (frying, roasting and grilling; p < 0.05); the same behaviour was found in the large intestine for healthy children. Zn bioaccesibility in the large intestine varied statistically according to the subjects' idiosyncrasies, and was higher in healthy children (p < 0.05) probably due to growth demands and different composition of the colonic microbiota. In healthy adults and children, the bioaccesible fractions were 33.0 ± 20.4 % for the small intestine, 16.4 ± 22.0 and 59.6 ± 29.9% for the large one, and the non-bioaccessible ones 50.6 ± 19.9 and 7.4 ± 9.1%, respectively.

Influence of nutrients on the bioaccessibility and transepithelial transport of polybrominated diphenyl ethers measured using an in vitro method and Caco-2 cell monolayers

Previous research has shown the absorption of polybrominated diphenyl ethers (PBDEs) in the human gastrointestinal tract, but limited attention has been given to the influence of nutrients on PBDE absorption from food matrices. We investigated the effects of nutrients (oil, starch, protein, and dietary fiber) on the absorption and transport of PBDEs in a Caco-2 cell model and bioaccessibility of PBDEs by an in vitro gastrointestinal digestion method. The results showed that the accumulation ratios of PBDE congeners in Caco-2 cells were higher in the nutrient addition groups (oil: 26.7-50.6%, starch: 27.0-58.7%, protein: 12.1-44.1%, and dietary fiber: 28.2-55.1%) than the control group (7.17-36.1%), whereas the transport ratios were lower (oil: 2.30-7.20%, starch: 1.55-9.15%, protein: 1.04-8.78%, and dietary fiber: 0.85-7.04%) than control group (3.78-11.1%). Additionally, the PBDE bioaccessibility could be increased by adding the nutrients, particularly oil and starch. This study clarified the differences in PBDE absorption in the presence of nutrients using the in vitro digestion and Caco-2 cell model. The findings showed that nutrients were an important factor that promoted PBDE absorption in the gastrointestinal tract. Therefore, it is important to focus on a novel dietary strategy of food consumption with contaminant compounds to protect human health.

In vitrobioaccessibility and speciation changes of selenium inPleurotus eryngiiduring the growing stage

The production ofPleurotus eryngiiby selenium (Se) biofortification is an effective way to improve the demand for Se in humans.

A pilot duplicate diet study on manganese, selenium and chromium intakes in institutionalised children and adolescents from Guatemala

Hidden hunger occurs in the presence of an otherwise nutritionally or energetically appropriate diet that is deficient in essential vitamins and minerals. Guatemala has the highest rate of child malnutrition in Latin America and the prevalence of hidden hunger is high. The aim of this study was to determine the Mn, Se and Cr dietary intakes in Guatemalan institutionalised children (4-14 years), a population group at high risk of mineral deficiency. For this purpose, the contents of Mn, Se and Cr were analysed in a duplicate diet (for 7 consecutive days) by electrothermal atomisation-atomic absorption spectrophotometry following acid digestion. Mn, Se and Cr intakes from the duplicate diets were in the range of 1·3-2·31 mg/d, 58·7-69·6 µg/d and 6·32-27·57 µg/d, respectively. Mn and Cr values were below current recommended daily intakes. A cereal- and legumes-based diet is habitually consumed by this population. Local vegetables, fruits and nutritional supplements are included daily, but the consumption of fish, meat, eggs and dairy products is very infrequent or negligible. Mean daily energy intake from the 7-d diet was 8418·2 kJ (2012 kcal), with a macronutrient energy distribution of carbohydrates 69·4 %, proteins 12·3 % and fats 18·3 %. Correlations between Mn, Se and Cr intakes and energy and other nutrient intakes were also evaluated. The present findings will help establish new nutritional strategies for this and similar population groups.

Daily dietary intakes of zinc, copper, lead, and cadmium as determined by duplicate portion sampling combined with either instrumental analysis or the use of food composition tables, Shiraz, Iran

Estimation of essential and toxic element intakes is crucial to evaluate the risks of deficiency or toxicity. The purpose of this study was to investigate and also to compare the dietary intakes of zinc (Zn) and copper (Cu) by adults living in Shiraz, Iran, determined by two procedures: duplicate portion sampling of 21 hospital meals combined with either instrumental analysis (voltammetric measurement) or the use of food composition tables (FCTs). The level of exposure to lead (Pb) and cadmium (Cd) was evaluated as well. The daily Zn intakes of both methods were not significantly different and were higher than the RDA values except the value measured by the instrumental analysis which was lower than the RDA established for a male adult. Daily intake of Cu determined by instrumental analysis was significantly lower and closer to RDA for adults compared with the value estimated by FCTs. The dietary intakes of Pb and Cd were 313 and 61% of the respective provisional tolerable weekly intakes (PTWIs), respectively. The accuracy of two methods used for estimation of Zn intake was similar. In the case of Cu, the use of FCTs, in which the influence of environmental conditions and dietary habits of meal preparation is not taken into account, overestimated dietary intake. The risk of zinc deficiency was found in adult males. Moreover, the estimated intake of Pb, but not Cd, could be a cause of concern for Shiraz population. Thus, conducting regular periodic studies to assess the dietary intake of mentioned elements are recommended.

Bioaccessibility of metals in alloys: evaluation of three surrogate biofluids

Bioaccessibility in vitro tests measure the solubility of materials in surrogate biofluids. However, the lack of uniform methods and the effects of variable test parameters on material solubility limit interpretation. One aim of this study was to measure and compare bioaccessibility of selected economically important alloys and metals in surrogate physiologically based biofluids representing oral, inhalation and dermal exposures. A second aim was to experimentally test different biofluid formulations and residence times in vitro. A third aim was evaluation of dissolution behavior of alloys with in vitro lung and dermal biofluid surrogates. This study evaluated the bioaccessibility of sixteen elements in six alloys and 3 elemental/metal powders. We found that the alloys/metals, the chemical properties of the surrogate fluid, and residence time all had major impacts on metal solubility. The large variability of bioaccessibility indicates the relevancy of assessing alloys as toxicologically distinct relative to individual metals.

The probiotic bacterial strain Lactobacillus fermentum D3 increases in vitro the bioavailability of Ca, P, and Zn in fermented goat milk

We determined calcium, magnesium, phosphorus and zinc levels in a total of 27 samples of commercial goat- and cow-milk fermented products and 9 samples of a goat-milk fermented product with addition of a probiotic bacterial strain, Lactobacillus fermentum D3, manufactured experimentally by our research group. Atomic absorption spectroscopy with flame atomization and UV/VIS spectrophotometry were used as analytic techniques. The results of an in vitro digestion process showed that the bioavailability of calcium, phosphorus, and zinc was significantly higher in our fermented milk containing the probiotic bacterial strain than it was in commercial goat-milk fermented products. Furthermore, our product showed a significantly higher bioavailability of calcium and zinc compared to goat- and cow-milk fermented products made with other microorganisms. We conclude that, in in vitro assays, strain D3 seems to increase the bioavailability of these minerals and that this new product may constitute a better source of bioavailable minerals compared to other products already on the market.

Dialysability of magnesium and calcium from hospital duplicate meals: influence exerted by other elements

Total and dialysable magnesium and calcium levels and corresponding dialysabilities were measured in duplicate meals (n = 108) during 36 consecutive days. The interaction exerted by other nutrients and energy on them was also performed. Total mean magnesium and calcium fractions of 113.9 +/- 98.3 and 337.2 +/- 278.9 mg/meal respectively, were found. The Mg and Ca levels supplied by meals are positively (p < 0.05) correlated with macronutrient contents (carbohydrates and proteins). The mean dialysable Mg and Ca fractions were 56.9 +/- 36.3 and 127.4 +/- 112.3 mg/meal (50.4 +/- 13.2 and 37.8 +/- 10.7% as dialysabilities, respectively). Total Mg and Ca levels are significantly correlated with corresponding element dialysabilities (p < 0.05). For both minerals, significant correlations between their total and dialysable fractions and between their dialysable level and dialysabilities were noted (p < 0.01). The mean Mg and Ca daily dietary intakes (DDI) were 341.7 +/- 68.0 and 1,011.6 +/- 424.4 mg/day, respectively. For Ca and Mg the existence of similarities in their behaviour in meals and absorptive processes has been found. Duplicate meals with raw vegetables are good sources of bioaccessible Mg. High Ca dialysability has been found in the analysed meals. The fish and products constitute a good source of bioaccessible Ca. Mg, Ca, zinc, and chromium levels enhanced significantly the Mg dialysability. The Ca dialysability rose significantly with dialysable Ca and chromium fractions (p < 0.05).

Iron dialyzability from hospital duplicate meals: daily intake

Both total and dialyzable iron levels and corresponding dialyzability were determined in 108 duplicate meals during 36 consecutive days. Total mean iron fraction of 5.90 +/- 4.97 mg was found in the meals. The iron supplied by the meals is directly and significantly (p < 0.05) correlated with macromicronutrient content (carbohydrates, fiber, and protein). The mean iron dialyzability (4.81 +/- 3.25%) was low and not significantly different among the three primary meals (breakfast, lunch, and dinner). Significant interactions of several minerals on iron levels were found (p < 0.05). Iron dialyzability was only statistically influenced by zinc dialyzability in meals (p < 0.05). The dialyzed iron fraction present in meals was significantly correlated with protein and ascorbic acid levels (p < 0.01). The mean iron daily dietary intake was 17.7 +/- 6.91 mg. The hospital meals provided enough iron. Foods of animal origin are primary sources of iron in diet.