Effect of dephytinization on bioavailability of iron, calcium and zinc from infant cereals assessed in the Caco-2 cell model

Application of In Vitro Digestion Models in the Evaluation of Dietary Supplements

Nowadays, dietary supplements are a permanent part of our diet. Using various simulated in vitro digestive models, the bioavailability of dietary supplement ingredients has also been investigated. In most cases, static models are used instead of dynamic ones. This article focuses on the division of applications of in vitro methods, such as assessing the quality of dietary supplements (in chemical and pharmaceutical form), the impact of diet on the assessment of the bioavailability of product ingredients, the impact of supplement ingredients on the state of intestinal microflora, and the development of new products using various encapsulation methods. The review included publications from 2000 to 2024 showing the use of in vitro methods in dietary supplements containing polysaccharides, proteins, elements, vitamins, and bioactive substances, as well as probiotic and prebiotic products. The impact of components in dietary supplements on the human digestive tract and their degree of bioaccessibility were determined through the use of in vitro methods. The application of in vitro methods has also become an effective tool for designing new forms of dietary supplements in order to increase the availability and durability of labile ingredients in these products.

Effects of Daidzein, Tempeh, and a Probiotic Digested in an Artificial Gastrointestinal Tract on Calcium Deposition in Human Osteoblast-like Saos-2 Cells

Adequate calcium intake is crucial for the prevention and treatment of bone-related issues. Developing a nutritional source of readily bioavailable calcium is particularly significant for individuals deficient in this essential element and at risk of developing osteoporosis. This research aimed to evaluate the impact of tempeh (T), daidzein (D), and Lactobacillus acidophilus (LA) within a simulated intestinal environment consisting of Caco-2 epithelial and Saos-2 cells, focusing on their implications for bone mineralization mechanisms. In the initial phase, calcium bioaccessibility from calcium citrate (CaCt), LA, D, the daidzein combination D-CaCt-LA (D1:1:1), and the tempeh combination T-CaCt-LA (T1:1:1) was assessed through digestion simulation. The calcium content of both untreated and digested samples was determined using atomic absorption spectrometry (AAS). In the subsequent stage, the digested samples were used to induce intestinal absorption in differentiated enterocyte-like Caco-2 cells. The permeable fractions were then evaluated in a culture of osteoblast-like Saos-2 cells. Preliminary cellular experiments employed the MTT assay to assess cytotoxicity. The results indicated that the analyzed products did not influence the deposition of extracellular calcium in Saos-2 cells cultured without mineralization stimulators. The combined formulations of permeable fractions of digested CaCt, LA, D, and T demonstrated the capacity to enhance the proliferation of Saos-2 cells. In Saos-2 cells, D, D1:1:1, and LA showed no discernible impact on intracellular calcium accumulation, whereas T and T1:1:1 reduced the calcium deposits. Additionally, mRNA transcripts and alkaline phosphatase (ALP) activity levels in Saos-2 cells cultured without mineralization induction were unaffected by the analyzed products. An examination of the products revealed no discernible effect on ALP activity or mRNA expression during Saos-2 cell differentiation. Our findings suggest that tempeh, daidzein, and L. acidophilus did not positively impact cellular calcium deposition in Saos-2 cells. However, tempeh, daidzein and its combination, and L. acidophilus might enhance the process of osteogenic differentiation in Saos-2 cells. Nevertheless, this study did not identify any synergistic impact on calcium deposition and the process of osteogenic differentiation in Saos-2 cells of isoflavones and probiotics.

Effect of Processing Methods on Antinutritional Factors (Oxalate, Phytate, and Tannin) and Their Interaction with Minerals (Calcium, Iron, and Zinc) in Red, White, and Black Kidney Beans

The purpose of this study was to assess how different processing techniques affected mineral compositions, antinutritional factors, and their interactions in red, white, and black kidney beans consumed in Ethiopia. Mineral contents were found to be 41-44, 58-78, and 112-126 mg Ca/100 g in the raw, soaked, and cooked samples, respectively. Iron content in the raw, soaked and cooked samples were found to be 2.77-2.97, 1.94-2.20 and 2.87-3.28 mg Fe/100 g, respectively, showing 26-30% loss on soaking followed by 33-48% increase on cooking. While Zn content in the raw, soaked and cooked samples were found to be 2.47-3.26, 3.34-4.68 and 2.83-3.31 mg Zn/100 g, respectively, showing 35-43% increase on soaking followed by 15-29% decrease on cooking. In the case of antinutrients, both treatments showed incredible decrements. Phytate in the raw samples was 178-179 mg/100 g and showed a 12-16% decrement on soaking and a 37-38% decrement up on cooking, oxalate was 1.5-1.8 mg/100 g in the raw samples and showed a 4.4-13% decrement during treatments, and tannin in the raw samples was 102-160 mg/100 g and showed a 23-30% decrement on soaking, followed by 21-41% during cooking. Phytate : Ca and oxalate : Ca molar ratios in soaked and cooked samples were within the critical values in the raw samples. In contrast, phytate : Zn and Ca × phytate : Zn in all treatments were found to be within the critical value, confirming the good bioavailability of zinc in all the samples, while phytate : Fe was found over the critical value, showing its poor availability.

Nutritional, antioxidant, carbohydrate hydrolyzing enzyme inhibitory activities, and glyceamic index of wheat bread as influence by bambara groundnut substitution

The research was designed to ascertain the potential of bambara groundnut inclusion in wheat bread to improve antioxidant activity, modulate carbohydrate hydrolyzing enzyme activities, and lower glyceamic index/ load. Protein (g/100 g) (11.2—11.73) and energy value (kcal/100 g) (421.5—435.5) of the bread were significantly higher than commercial wheat flour bread (CWF—10.45; 388.7). However, developed experimental bread samples exhibited higher growth performance in rats, free radical scavenging potentials, inhibitory activities against carbohydrate hydrolyzing enzymes and low glycemic index than other bread samples. Nevertheless, experimental bread samples were rated lower compared with the controls samples as regards organoleptic properties. The study authenticates that WBO3—25% wheat, and 75% bamabara groundnut WBO3 exhibits higher potentials as regards nutritional composition, growth indices, free radical scavenging potentials, ability to modulate carbohydrate hydrolyzing enzyme and lower glycemic index/ load. Hence, WBO3 may be recommended as functional bread for hyperglycemia prevention/ management.

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 β-carotene in combinations of bio fortified food sources of Fe and Zn (cowpea cooked with and without maceration: CM/CW, respectively) and β-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 β-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.

Optimization of nutritional and sensory qualities of complementary foods prepared from sorghum, soybean, karkade and premix in Benishangul - Gumuz region, Ethiopia

Consumption of nutritionally deficient complementary foods in developing countries is among the main contributing factors to infants and young children's malnutrition. Therefore, this study was aimed to optimize the nutritional and sensory properties of complementary food made from malted sorghum, blanched soybean, boiled karkade seeds and premix. A D-optimal mixture experimental design with 18 runs was generated by design expert software within in the constrained: 40-60% malted sorghum, 20-30% blanched soybean, 10-20% boiled karkade seeds and 10% premix (5.0% figl leaf powder, 4.5% sugar and 0.5% iodized table salt). Statistical model evaluation and optimization were done using D-optimal mixture design expert software. Sensory evaluation was conducted using 53 untrained panelists on two selected formulations and the control (local formulation). The study shows that with an increasing ratio of blanched soybean and boiled karkade seeds flour in the blend, a significant (p < 0.05) increase in protein, fat, energy and mineral contents, and a decrease in tannin and phytic acid contents of high mineral bioavailability except for oxalate: calcium ratio in the formulations were observed. The optimal blending ratio was 45.0% malted sorghum, 26.0% blanched soybean, and 19.0% boiled karkade seeds flour plus 10.0% premix. The gruel made from the new formula was significantly (p < 0.05) liked in terms of aroma, flavor, mouthfeel and overall acceptability than the control sample. The findings suggested that the optimal mix of these traditionally processed ingredients can potentially alleviate protein-energy malnutrition and micronutrient deficiency to mitigate expensive commercial infant complementary foods sold in the market.

Proximate, mineral and anti-nutrient compositions of oat grains (Avena sativa) cultivated in Ethiopia: implications for nutrition and mineral bioavailability

Oat (Avena sativa) is an underutilized cereal grain in Ethiopia from the Poaceae grass family. This study aimed to investigate the proximate, mineral, and anti-nutrient composition of three landrace varieties commonly used in certain districts of the country and compare them with two improved varieties of oats in Ethiopia. The proximate and mineral composition was determined using the Association of Official Analytical Chemists (AOAC) standard methods. Phytate and tannin contents were determined using the spectroscopic method, and oxalate was analyzed using HPLC. The bioavailability of minerals was also estimated. Results showed significant (p < 0.05) differences in proximate, mineral, and anti-nutrient compositions among studied varieties. The moisture, crude protein, crude fat, crude fiber, ash, and total carbohydrate contents were in the range between 8.5-9.8, 11.9–15.8, 6.7–10.3, 2.1–3.5, 1.2–1.3, and 72.6–74.3 g/100 g DM, respectively. Iron, copper, zinc, magnesium, calcium, and potassium contents were 2.5–3.0, 0.2–0.4, 1.6–2.0, 62.4–89.1, 44.0–102.7, and 241.7–258.3 mg/100 g DM, respectively. The oxalate, tannin, and phytate contents ranged from 28.2-71.4, 38.8–51.5, and 269.6–293.0 mg/100 g DM, respectively. Except for a few varieties of oats, the molar ratios were below the critical values. Results showed that both the landraces and improved varieties studied are an excellent source of valuable nutrients. Thus, the production and utilization of this crop in a few geographical locations and communities should be further encouraged in the rest areas of the country to benefit from this underutilized but nutritious crop.

Premilling treatments effects on nutritional composition, antinutritional factors, and in vitro mineral bioavailability of the improved Assosa I sorghum variety (Sorghum bicolor L.)

Sorghum (Sorghum bicolor L.) is among the staple cereal crops in different parts of Ethiopia. However, the presence of antinutritional factors restricts the digestion of proteins and bioavailability different minerals. Therefore, this study investigates the premilling treatments effects on nutritional composition, antinutritional factors, and in vitro mineral bioavailability of the improved Assosa I sorghum variety grown in Benishangul-Gumuz Region, Ethiopia. The experiment was conducted in a completely randomized design with single factor of premilling treatments (control, washing, soaking, and malting). Among evaluated premilling treatments, malting showed significant (p < .05) increase in terms of crude fiber, utilizable carbohydrate, gross energy, and sodium contents. As compared to the raw sorghum, premilling treatments reduced antinutritional contents from 55.81 to 27.4 mg/100 g for tannin, 156.15 to 70.50 mg/100 g for phytates, and 29.9 to 3.22 mg/100 g for oxalate. The premilling techniques also significantly (p < .05) improved in vitro mineral bioavailability as compared to unprocessed sorghum grains. Among the premilling treatments, malting showed significant difference (p < .05) in terms of reduction of tannins, phytates, and oxalate contents with relatively higher mineral bioavailability. In order to enhance the food and nutritional value of sorghum particularly for children and lactating mothers, it is recommended to germinated the grains. Flour from germinated grain also can be used in combination with other nutrient-dense foods to formulate healthy diets for children and maternal nutrition.

Biofortification and bioavailability of Zn, Fe and Se in wheat: present status and future prospects

Knowledge of genetic variation, genetics, physiology/molecular basis and breeding (including biotechnological approaches) for biofortification and bioavailability for Zn, Fe and Se will help in developing nutritionally improved wheat. Biofortification of wheat cultivars for micronutrients is a priority research area for wheat geneticists and breeders. It is known that during breeding of wheat cultivars for productivity and quality, a loss of grain micronutrient contents occurred, leading to decline in nutritional quality of wheat grain. Keeping this in view, major efforts have been made during the last two decades for achieving biofortification and bioavailability of wheat grain for micronutrients including Zn, Fe and Se. The studies conducted so far included evaluation of gene pools for contents of not only grain micronutrients as above, but also for phytic acid (PA) or phytate and phytase, so that, while breeding for the micronutrients, bioavailability is also improved. For this purpose, QTL interval mapping and GWAS were carried out to identify QTLs/genes and associated markers that were subsequently used for marker-assisted selection (MAS) during breeding for biofortification. Studies have also been conducted to understand the physiology and molecular basis of biofortification, which also allowed identification of genes for uptake, transport and storage of micronutrients. Transgenics using transgenes have also been produced. The breeding efforts led to the development of at least a dozen cultivars with improved contents of grain micronutrients, although land area occupied by these biofortified cultivars is still marginal. In this review, the available information on different aspects of biofortification and bioavailability of micronutrients including Zn, Fe and Se in wheat has been reviewed for the benefit of those, who plan to start work or already conducting research in this area.

Nutritional, Antinutritional and Phenolic Properties of Lima Bean (Phaseolus lunatus) Accessions: Underutilized Legume in Ethiopia

The study was aimed to evaluate nutritional compositions, anti- nutritional factors and antioxidant properties of lima bean accessions grown in East Shoa Zone, Ethiopia. The lima bean accessions were studied and compared for their nutritional composition, anti-nutritional factors and antioxidant properties. The result showed that lima bean accessions were good source of vital nutrients when compared to the commonly consumed legumes in Ethiopia. Particularly, lima bean accessions “LB8510” rich in crude protein whereas accession “LB85CH2” rich in crude fiber, total ash and iron and can be implemented for breeding, new product development and used as alternative source of nutrient rich to mitigate malnutrition prevalent in Ethiopia. Therefore, increasing its consumption, cultivation and promotion should be encouraged.

Impact of acidity regulator and excipient nutrients on digestive solubility and intestinal transport of calcium from calcium phosphate and carbonate

The aim of the current study was to investigate the effect of an acidity regulator (SPORIX®), lactose, and vitamin D₃ as excipient ingredients on digestive solubility and intestinal transport of calcium from four different calcium materials (tricalcium phosphate (TCP), fish bone (FB), nano-fish bone (NFB), and algae calcium (AC)) through an in vitro digestion model system combined with Caco-2 cells. The concentration of ionized calcium (Ca²⁺) in an aqueous fraction after in vitro digestion increased with the addition of SPORIX®, and it was further enhanced by adding SPORIX® + lactose + vitamin D₃ into TCP, FB, NFB, and AC, respectively. In particular, FB with SPORIX® + lactose + vitamin D₃ enhanced calcium ionization to 33.89 ± 0.69 mg g^-1, which was about 11.76 times higher than that of FB only. In the case of intestinal cellular uptake of calcium, there was no significant difference in all the tested calcium materials with SPORIX® + lactose + vitamin D₃. However, the absolute amount of intestinal transport of calcium in FB (43.95 ± 3.29 μg) was significantly higher than other calcium materials with the addition of SPORIX® + lactose + vitamin D₃ (p < 0.05). This study suggests that the co-consumption of SPORIX®, lactose, and vitamin D₃ with FB could enhance the calcium bioavailability by lowering pH as well as improving calcium intestinal transport by modulating the paracellular and transcellular uptake mechanism.

Proximate, mineral, and anti-nutrient compositions of underutilized plants of Ethiopia: Figl (Raphanus sativus L.), Girgir (Eruca sativa L) and Karkade (Hibiscus sabdariffa): Implications for in-vitro mineral bioavailability

In Ethiopia, particularly in the Benishangul-Gumuz region, there are several underutilized plants like Figl (Raphanus sativus), Girgir (Eruca sativa) and Karkade (Hibiscus sabdariffa) which are cultivated and consumed only by the local communities. However, information on nutrient, anti-nutrient contents and mineral bioavailability of edible parts of these plants are limited. Given this, leaves and roots of Figl, leaves of Girgir, calyces and seeds of Karkade were evaluated for their proximate, mineral and anti-nutrient contents following the standard analytical methods. The result on dry matter basis revealed that protein contents (26.32 g/100 g) were high for brown seeds of Karkade, dried leaves of Figl (26.71 g/100 g) and Girgir (24.23 g/100 g). The fat and energy contents were high for seeds of Karkade (15.58-18.00 g/100 g; 371.64-376.69 kcal/100 g). The fiber content was high for dried leaves of Figl (28.39 g/100 g) and low for calyces of Karkade (15.33-16.54 g/100 g). There was a significant difference (p < 0.05) in terms of mineral contents. The dried leaves of Figl were high in calcium, sodium, potassium, and phosphorus contents while dried leaves of Girgir were high in iron and zinc contents. With exception of oxalate content, seeds of Karkade were low in tannin, phytate and alkaloid. The phytate: mineral ratio analysis showed the bioavailability of iron is likely to be inhibited from roots of Figl and calyces of Karkade; zinc bioavailability from calyces of Karkade which suggests processing for phytate reduction is important. The result showed the seeds of Karkade are good sources of protein, fat and energy with low antinutritional contents that may favor mineral bioavailability with potential for utilization in baby food formulations to alleviate protein energy malnutrition. The leaves of Figl and Girgir can also be exploited in different food formulations to improve macro and micronutrient deficiency.

Nutritional and antinutritional evaluation of complementary foods formulated from maize, pea, and anchote flours

This study was aimed to evaluate nutritional and antinutritional contents of complementary foods from locally available and affordable raw materials (maize, pea, and anchote) grown in Western Ethiopia. The six formulated complementary diets analyzed for their proximate, mineral, and antinutritional continents were compared with Codex standards. The mineral ratios and molar ratios of the formulated diets were also evaluated and compared with each standard values. Six formulations were generated by d-optimal mixture design. The formulated ingredient ranges 45%-61% maize, 23%-31% pea, and 14%-28% anchote. Design-Expert® 6 (Stat-Ease) was used to constrain the three components. The formulated diets ranged from 14.92% to 20.99%, 5.95% to 9.94%, 2.75% to 3.41%, and 59.10% to 66.22% of protein, fat, fiber, and utilizable carbohydrate, respectively. Mineral contents (mg/100 g) of the formulated diet ranged from 225.45 to 261.32, 11.48 to 12.61, 2.73 to 3.00, 357.92 to 391.13, 298.55 to 332.63, 252.00 to 278.01, and 44.26 to 51.56 for calcium, iron, zinc, phosphorous, potassium, sodium and magnesium, respectively. The proximate and mineral contents of the formulated diet 5 meet the Codex standards, except the fat contents of the complementary food standards. The molar ratios of the formulated diets in this study were below standard reference and which show the high mineral bioavailability in all the formulated diets. The results of the study revealed that the formulated diets contain very low antinutritional factors and high mineral bioavailability. The paper's findings show that the complementary food formulated from maize, pea, and anchote flours particularly diet 5 may be suitable to alleviate protein energy malnutrition and it can be used as a substitute for the expensive commercial complementary food.

A Guide to Human Zinc Absorption: General Overview and Recent Advances of In Vitro Intestinal Models

Zinc absorption in the small intestine is one of the main mechanisms regulating the systemic homeostasis of this essential trace element. This review summarizes the key aspects of human zinc homeostasis and distribution. In particular, current knowledge on human intestinal zinc absorption and the influence of diet-derived factors on bioaccessibility and bioavailability as well as intrinsic luminal and basolateral factors with an impact on zinc uptake are discussed. Their investigation is increasingly performed using in vitro cellular intestinal models, which are continually being refined and keep gaining importance for studying zinc uptake and transport via the human intestinal epithelium. The vast majority of these models is based on the human intestinal cell line Caco-2 in combination with other relevant components of the intestinal epithelium, such as mucin-secreting goblet cells and in vitro digestion models, and applying improved compositions of apical and basolateral media to mimic the in vivo situation as closely as possible. Particular emphasis is placed on summarizing previous applications as well as key results of these models, comparing their results to data obtained in humans, and discussing their advantages and limitations.

Bioavailability Assessment of Copper, Iron, Manganese, Molybdenum, Selenium, and Zinc from Selenium-Enriched Lettuce

Cu, Fe, Mn, Mo, Selenium (Se), and Zn bioavailability from selenate- and selenite-enriched lettuce plants was studied by in vitro gastrointestinal digestion followed by an assay with Caco-2 cells. The plants were cultivated in the absence and presence of two concentrations (25 and 40 µmol/L of Se). After 28 days of cultivation, the plants were harvested, dried, and evaluated regarding the total concentration, bioaccessibility, and bioavailability of the analytes. The results showed that biofortification with selenate leads to higher Se absorption by the plant than biofortification with selenite. For the other nutrients, Mo showed high accumulation in the plants of selenate assays, and the presence of any Se species led to a reduction of the plant uptake of Cu and Fe. The accumulation of Zn and Mn was not strongly influenced by the presence of any Se species. The bioaccessibility values were approximately 71%, 10%, 52%, 84%, 71%, and 86% for Cu, Fe, Mn, Mo, Se, and Zn, respectively, and the contribution of the biofortified lettuce to the ingestion of these minerals is very small (except for Se and Mo). Due to the low concentrations of elements from digested plants, it was not possible to estimate the bioavailability for some elements, and for Mo and Zn, the values are below 6.9% and 3.4% of the total concentration, respectively. For Se, the bioavailability was greater for selenite-enriched than selenate-enriched plants (22% and 6.0%, respectively), because selenite is biotransformed by the plant to organic forms that are better assimilated by the cells.

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.

Complementary feeding and effect of spontaneous fermentation on anti-nutritional factors of selected cereal-based complementary foods

Background

Malnutrition has been responsible directly or indirectly for 10.9 million deaths worldwide annually among children under five. Childhood malnutrition is highly related to poor nutritional quality diet in developing countries where there is limited access to animal based foods. Most foods consumed by young children are cereal based which contain high amounts of anti-nutritional factors. Fermentation is thought to significantly lower the content of anti-nutrients in cereal grains. This study therefore, aimed to determine complementary feeding practices and effect of spontaneous fermentation on anti-nutritional factors and mineral contents of selected cereals.

Methods

Cross sectional survey was conducted in Ebinat district to determine complementary feeding practices among 324 lactating mothers. Laboratory analysis was carried out for teff and wheat cereal grains to determine the effect of spontaneous fermentation on anti-nutrients as well as mineral contents.

Results

Prevalence of appropriate complementary feeding practice was 1.5%. Fermentation of the sampled cereals for 12 h significantly (p < 0.05) reduced total phytate and total tannin. The reduction continued and most of the reduction of phytate and tannin contents occurred during the 72 h of fermentation for both cereal samples. However, the reduction for some fermentation times was not statistically significant. A significant (p < 0.05) variation was also noticed in the total amounts of calcium, iron and zinc in both sampled cereals within the 72 h of fermentation.

Conclusion

Prevalence of appropriate complementary feeding practice was very low. There were significant reductions of phytate and tannin contents with concomitant increments of minerals after fermentation of cereals. Phytate: mineral ratios were significantly decreased after fermentation for all the parameters examined. It is recommended to ferment cereals while preparing complementary foods for children so as to enhance their micronutrient uptake.

Evaluation of mineral bioavailability and heavy metal content in indigenous food plant wild yams (Dioscorea spp.) from Koraput, India

Wild yam (Dioscorea spp.) tubers, an indigenous food makes a significant contribution to the diets of tribal people of Koraput, India. However, there is dearth of documented information of their mineral bioavailability and heavy metal content. To know their quality and safety concerns about their use, minerals and heavy metal concentrations were evaluated in eight wild and one cultivated yam species from Koraput. The samples were further investigated for their antinutrients to determine bioavailability of minerals. The majority of the wild yam tubers were rich in some of the essential minerals like calcium (18.08-74.79 mg/100 g), iron (11.15-28.61 mg/100 g), zinc (2.11-6.21 mg/100 g) and phosphorous (179-248 mg/100 g). The heavy metals concentration (mg/100 g) ranged from: cobalt (1.06-1.98), nickel (0.30-0.89), chromium (2.10-4.53) and lead (0.11-0.93) among the studied yam species. These values were lower than the recommended tolerable levels proposed by WHO Expert Committee on Food Additives. Based on these results of molar ratio between phytate and Fe, Zn and Ca were below the suggested critical values indicating the bioavailability of Fe, Zn and Ca to be high. The study also suggests these wild yam species as the safe food sources for mass consumption and can be beneficial for health.

Polyamines regulating phytic acid degradation in mung bean sprouts

BACKGROUND

Polyamines are essentially involved in cell division and differentiation. Transport of polyamines is adenosine triphosphate (ATP)-dependent, while phytic acid is the major reserve of phosphate essential to the energy-producing machinery of cells. Thus polyamines might enhance phytic acid degradation during mung bean germination. In this study, different polyamines (putrescine (Put), spermidine (Spd) and spermine (Spm)) and dicyclohexylamine (DCHA, an inhibitor of Spd synthesis) were applied to investigate the function of polyamines on phytic acid degradation.

RESULTS

Spd exhibited the best effect at the same concentration. Simultaneously, exogenous Spd improved sprout growth and enhanced the accumulation of gibberellin acid 3 (GA₃ ), indole-3-acetic acid (IAA), abscisic acid (ABA) and cytokinin (CTK). This must be due to the increased endogenous polyamine contents. Apart from dramatically reducing phytic acid content, Spd resulted in the up-regulation of PA, PAP, MIPP and ALP transcript levels and the enhancement of phytase and acid phosphatase activities. However, DCHA application caused the opposite results, because it decreased endogenous polyamine contents. Furthermore, Spd alleviated the DCHA-induced inhibitory effect to some extent.

CONCLUSION

Overall, polyamines, especially Spd, could accelerate phytic acid degradation in mung bean sprouts by inducing the synthesis of endogenous polyamines and phytohormones and enhancing the growth of sprouts. © 2017 Society of Chemical Industry.

Interspecific and intergeneric hybridization as a source of variation for wheat grain quality improvement

The hybridization events with wild relatives and old varieties are an alternative source for enlarging the wheat quality variability. This review describes these process and their effects on the technological and nutritional quality. Wheat quality and its end-uses are mainly based on variation in three traits: grain hardness, gluten quality and starch. In recent times, the importance of nutritional quality and health-related aspects has increased the range of these traits with the inclusion of other grain components such as vitamins, fibre and micronutrients. One option to enlarge the genetic variability in wheat for all these components has been the use of wild relatives, together with underutilised or neglected wheat varieties or species. In the current review, we summarise the role of each grain component in relation to grain quality, their variation in modern wheat and the alternative sources in which wheat breeders have found novel variation.

Variability in iron, zinc and phytic acid content in a worldwide collection of commercial durum wheat cultivars and the effect of reduced irrigation on these traits

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Malnutrition is a major challenge worldwide associated with diets rich in cereals.

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Durum wheat is important source of calories and protein in developing countries.

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A modified scale-down method to quantify phytate was validated.

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46 durum varieties were analyzed for Fe, Zn and phytate (bioavailability) content.

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Variation was detected for Phy:Fe (12.1–29.6) and Phy:Zn (16.9–23.6) molar ratios.

Diets very rich in cereals have been associated with micronutrient malnutrition, and the biofortification of them, has been proposed as one of the best approaches to alleviate the problem. Durum wheat is one of the main sources of calories and protein in many developing countries. In this study, 46 durum varieties grown under full and reduced irrigation, were analyzed for micronutrients and phytate content to determine the potential bioavailability of the micronutrients. The variation was 25.7–40.5 mg/kg for iron and of 24.8–48.8 mg/kg for zinc. For phytate determination (0.462–0.952 %), a modified methodology was validated in order to reduce testing costs while speeding up testing time. Variation was detected for phytate:iron and zinc molar ratios (12.1–29.6 and 16.9–23.6, respectively). The results could be useful to generate varieties with appropriate levels of phytate and micronutrients, which can lead to the development of varieties rich in micronutrients to overcome malnutrition.

Transgenic expression of phytase in wheat endosperm increases bioavailability of iron and zinc in grains

Phytate is a major constituent of wheat seeds and chelates metal ions, thus reducing their bioavailability and so the nutritional value of grains. Transgenic plants expressing heterologous phytase are expected to enhance degradation of phytic acid stored in seeds and are proposed to increase the in vitro bioavailability of mineral nutrients. Wheat transgenic plants expressing Aspergillus japonicus phytase gene (phyA) in wheat endosperm were developed till T₃ generation. The transgenic lines exhibited 18-99 % increase in phytase activity and 12-76 % reduction of phytic acid content in seeds. The minimum phytic acid content was observed in chapatti (Asian bread) as compared to flour and dough. The transcript profiling of phyA mRNA indicated twofold to ninefold higher expression as compared to non transgenic controls. There was no significant difference in grain nutrient composition of transgenic and non-transgenic seeds. In vitro bioavailability assay for iron and zinc in dough and chapatti of transgenic lines revealed a significant increase in iron and zinc contents. The development of nutritionally enhanced cereals is a step forward to combat nutrition deficiency for iron and zinc in malnourished human population, especially women and children.

Iron-Binding Capacity of Defatted Rice Bran Hydrolysate and Bioavailability of Iron in Caco-2 Cells

The present study was aimed at utilizing defatted rice bran (DRB) protein as an iron-binding peptide to enhance iron uptake in humans. DRB samples were treated with Alcalase and Flavourzyme, and the total extractable peptides were determined. Furthermore, the iron-binding capacities of the DRB protein hydrolysates were determined, whereas iron bioavailability studies were conducted using an in vitro digestion and absorption model (Caco-2 cells). The results showed that the DRB protein hydrolysates produced by combined Alcalase and Flavourzyme hydrolysis had the best iron-binding capacity (83%) after 90 min of hydrolysis. The optimal hydrolysis time to produce the best iron-uptake in Caco-2 cells was found to be 180 min. The results suggested that DRB protein hydrolysates have potent iron-binding capacities and may enhance the bioavailability of iron, hence their suitability for use as iron-fortified supplements.

Proximate, mineral, and antinutrient compositions of indigenous Okra (Abelmoschus esculentus) pod accessions: implications for mineral bioavailability

The promotion and consumption of indigenous vegetables could help to mitigate food insecurity and alleviate malnutrition in developing countries. Nutrient and antinutrient compositions of eight accessions of Okra Pods were investigated. Molar ratios and mineral bioavailability of Okra pod accessions were also calculated and compared to the critical values to predict the implications for mineral bioavailability. Proximate and mineral composition of Okra pod accessions were determined using standard methods of Association of Official Analytical Chemists. The result of the study revealed that the proximate composition (g/100 g) in dry weight basis was significantly (P < 0.05) varied and ranged: moisture/dry matter 9.69-13.33, crude protein 10.25-26.16, crude fat 0.56-2.49, crude fiber 11.97-29.93, crude ash 5.37-11.30, utilizable carbohydrate 36.66-50.97, and gross energy 197.26-245.55 kcal/100 g. The mineral concentrations (mg/100 g) were also significantly (P < 0.05) varied and ranged: calcium (111.11-311.95), Iron (18.30-36.68), potassium (122.59-318.20), zinc (3.83-6.31), phosphorus (25.62-59.72), and sodium (3.33-8.31) on dry weight bases. The Okra Pods of "OPA#6" accession contained significantly higher amounts of crude protein, total ash, crude fat, calcium, iron, and zinc than all other accessions evaluated in this study. The results of antinutrients analysis showed that, except phytate, tannin, and oxalate contents of all the accessions were significantly (P < 0.05) varied. The range of phytate, tannin, and oxalate contents (mg/100 g) for Okra pod accessions studied were as follows: 0.83-0.87, 4.93-9.90, and 0.04-0.53, respectively. The calculated molar ratios of phytate: calcium, phytate: iron, phytate: zinc, oxalate: calcium and [Phytate][Calcium]/[Zinc] were below the critical value and this indicate that the bioavailability of calcium, iron, and zinc in these accessions could be high. The results of the study revealed that Okra pod contain appreciable amount of vital nutrients like protein, fiber, calcium, iron, and zinc and low in antinutrient contents with high mineral bioavailability. Therefore, increase in the production and consumption of these nutrient-rich indigenous Okra pods will help to supplement/formulate the diets and alleviate the problems associated with malnutrition in the country.

Combating Mineral Malnutrition through Iron and Zinc Biofortification of Cereals

 Iron and zinc are 2 important nutrients in the human diet. Their deficiencies in humans lead to a variety of health-related problems. Iron and zinc biofortification of cereals is considered a cost-effective solution to overcome the malnutrition of these minerals. Biofortification aims at either increasing accumulation of these minerals in edible parts, endosperm, or to increase their bioavailability. Iron and zinc fertilization management positively influence their accumulation in cereal grains. Regarding genetic strategies, quantitative genetic studies show the existence of ample variation for iron and zinc accumulation as well as inhibitors or promoters of their bioavailability in cereal grains. However, the genes underlying this variation have rarely been identified and never used in breeding programs. Genetically modified cereals developed by modulation of genes involved in iron and zinc homeostasis, or genes influencing bioavailability, have shown promising results. However, iron and zinc concentration were quantified in the whole grains during most of the studies, whereas a significant proportion of them is lost during milling. This makes it difficult to realistically assess the effectiveness of the different strategies. Moreover, modifications in the accumulation of toxic elements, like cadmium and arsenic, that are of concern for food safety are rarely determined. Trials in living organisms with iron- and zinc-biofortified cereals also remain to be undertaken. This review focuses on the common challenges and their possible solutions related to agronomic as well as genetic iron and zinc biofortification of cereals.

Application of bifidobacterial phytases in infant cereals: effect on phytate contents and mineral dialyzability

Phytase activity was recently described in probiotic bifidobacterial strains, opening the possibilities for their use in foods, due to the generally regarded as safe/qualified presumption of safety status of these bacteria. Two raw materials for infant cereals (multicereal and gluten-free) were examined by measuring the myo-inositol phosphates content and the in vitro Ca, Fe, and Zn availability after a dephytinization process with purified phytases from Bifidobacterium longum spp. infantis and Bifidobacterium pseudocatenulatum. Treatment with both enzymes reduced the contents of phytate as compared to control samples (untreated or treated with fungal phytase) and led to increased levels of myo-inositol triphosphate. Dephytinization followed by an in vitro model of intestinal digestion increased the solubility of Zn. However, phytase treatment did not increase significantly the mineral dialyzability as compared to untreated samples. This is the first example of the application of purified bifidobacterial phytases in food processing and shows the potential of these enzymes to be used in products for human consumption.

Biofortification and bioavailability of rice grain zinc as affected by different forms of foliar zinc fertilization

Background

Zinc (Zn) biofortification through foliar Zn application is an attractive strategy to reduce human Zn deficiency. However, little is known about the biofortification efficiency and bioavailability of rice grain from different forms of foliar Zn fertilizers.

Methodology/Principal Findings

Four different Zn forms were applied as a foliar treatment among three rice cultivars under field trial. Zinc bioavailability was assessed by in vitro digestion/Caco-2 cell model. Foliar Zn fertilization was an effective agronomic practice to promote grain Zn concentration and Zn bioavailability among three rice cultivars, especially, in case of Zn-amino acid and ZnSO₄. On average, Zn-amino acid and ZnSO₄ increased Zn concentration in polished rice up to 24.04% and 22.47%, respectively. On average, Zn-amino acid and ZnSO₄ increased Zn bioavailability in polished rice up to 68.37% and 64.43%, respectively. The effectiveness of foliar applied Zn-amino acid and ZnSO₄ were higher than Zn-EDTA and Zn-Citrate on improvement of Zn concentration, and reduction of phytic acid, as a results higher accumulation of bioavailable Zn in polished rice. Moreover, foliar Zn application could maintain grain yield, the protein and minerals (Fe and Ca) quality of the polished rice.

Conclusions

Foliar application of Zn in rice offers a practical and useful approach to improve bioavailable Zn in polished rice. According to current study, Zn-amino acid and ZnSO₄ are recommended as excellent foliar Zn forms to ongoing agronomic biofortification.

Application of in vitro bioaccessibility and bioavailability methods for calcium, carotenoids, folate, iron, magnesium, polyphenols, zinc, and vitamins B(6), B(12), D, and E

A review of in vitro bioaccessibility and bioavailability methods for polyphenols and selected nutrients is presented. The review focuses on in vitro solubility, dialyzability, the dynamic gastrointestinal model (TIM)™, and Caco-2 cell models, the latter primarily for uptake and transport, and a discussion of how these methods have been applied to generate data for a range of nutrients, carotenoids, and polyphenols. Recommendations are given regarding which methods are most justified for answering bioaccessibility or bioavailability related questions for specific nutrients. The need for more validation studies in which in vivo results are compared to in vitro results is also discussed.

Effect of zinc sulfate fortification in germinated brown rice on seed zinc concentration, bioavailability, and seed germination

Rice is the staple food for more than half of the world's population and, hence, the main source of a vital micronutrient, zinc (Zn). Unfortunately, the bioavailability of Zn from rice is very low not only due to low content but also due to the presence of some antinutrients such as phytic acid. We investigated the effect of germination and Zn fortification treatment on Zn bioavailability of brown rice from three widely grown cultivars using the Caco-2 cell model to find a suitable fortification level for producing germinated brown rice. The results of this study showed that Zn content in brown rice increased significantly (p < 0.05) as the external Zn concentrations increased from 25 to 250 mg/L. In contrast, no significant influence (p > 0.05) on germination percentage of rice was observed when the Zn supply was lower than 150 mg/L. Zn fortification during the germination process has a significant impact on the Zn content and finally Zn bioavailability. These findings may result from the lower molar ratio of phytic acid to Zn and higher Zn content in Zn fortified germinated brown rice, leading to more bioavailable Zn. Likewise, a significant difference (p < 0.05) was found among cultivars with respect to the capacity for Zn accumulation and Zn bioavailability; these results might be attributed to the difference in the molar ratio of phytic acid to Zn and the concentration of Zn among the cultivars evaluated. Based on global intake of Zn among the world population, we recommend germinated brown rice fortified with 100 mg/L ZnSO(4) as a suitable concentration to use in the germination process, which contains high Zn concentration and Zn bioavailability. In the current study, the cultivar Bing91185 fortified with Zn through the germination process contained a high amount as well as bioavailable Zn, which was identified as the most promising cultivar for further evaluation to determine its efficiency as an improved source of Zn for target populations.

Whole grains: benefits and challenges

Inclusion of whole grains (WG) in the diet is recommended in dietary guidance around the world because of their associations with increased health and reduced risk of chronic disease. WGs are linked to reduced risk of obesity or weight gain; reduced risk of cardiovascular disease (CVD), including coronary heart disease (CHD), hypertension, and stroke; improved gut health and decreased risk of cancers of the upper gut; perhaps reduced risk of colorectal cancer; and lower mortality rate. The 2005 United States Dietary Guidelines Advisory Committee has recommended that consumers make "half their grains whole." Yet, whole grains are puzzling both consumers and scientists. Scientists are trying to determine whether their health benefits are due to the synergy of WG components, individual WG components, or the fact that WG eaters make many of the recommended diet and lifestyle choices. Consumers need to understand the WG benefits and how to identify WG foods to have incentive to purchase and use such foods. Industry needs to develop great-tasting, clearly-labeled products. With both these factors working together, it will be possible to change WG consumption habits among consumers.

Biofortification and bioavailability of rice grain zinc as affected by different forms of foliar zinc fertilization

BACKGROUND

Zinc (Zn) biofortification through foliar Zn application is an attractive strategy to reduce human Zn deficiency. However, little is known about the biofortification efficiency and bioavailability of rice grain from different forms of foliar Zn fertilizers.

METHODOLOGY/PRINCIPAL FINDINGS

Four different Zn forms were applied as a foliar treatment among three rice cultivars under field trial. Zinc bioavailability was assessed by in vitro digestion/Caco-2 cell model. Foliar Zn fertilization was an effective agronomic practice to promote grain Zn concentration and Zn bioavailability among three rice cultivars, especially, in case of Zn-amino acid and ZnSO(4). On average, Zn-amino acid and ZnSO(4) increased Zn concentration in polished rice up to 24.04% and 22.47%, respectively. On average, Zn-amino acid and ZnSO(4) increased Zn bioavailability in polished rice up to 68.37% and 64.43%, respectively. The effectiveness of foliar applied Zn-amino acid and ZnSO(4) were higher than Zn-EDTA and Zn-Citrate on improvement of Zn concentration, and reduction of phytic acid, as a results higher accumulation of bioavailable Zn in polished rice. Moreover, foliar Zn application could maintain grain yield, the protein and minerals (Fe and Ca) quality of the polished rice.

CONCLUSIONS

Foliar application of Zn in rice offers a practical and useful approach to improve bioavailable Zn in polished rice. According to current study, Zn-amino acid and ZnSO(4) are recommended as excellent foliar Zn forms to ongoing agronomic biofortification.

Biofortification for combating 'hidden hunger' for iron

Micronutrient deficiencies are responsible for so-called 'hidden undernutrition'. In particular, iron (Fe) deficiency adversely affects growth, immune function and can cause anaemia. However, supplementation of iron can exacerbate infectious diseases and current policies of iron therapy carefully evaluate the risks and benefits of these interventions. Here we review the approaches of biofortification of valuable crops for reducing 'hidden undernutrition' of iron in the light of the latest nutritional and medical advances. The increase of iron and prebiotics in edible parts of plants is expected to improve health, whereas the reduction of phytic acid concentration, in crops valuable for human diet, might be less beneficial for the developed countries, or for the developing countries exposed to endemic infections.

The Youngest Vegetarians

As the popularity of vegetarian diets increases, practitioners are likely to encounter vegetarian infants and toddlers. Vegetarian and vegan diets can be developed to meet nutrient needs and support growth of infants and toddlers. Key nutrients whose adequacy should be monitored in vegetarian/vegan diets include vitamin B12, calcium, vitamin D, iron, omega-3 fatty acids, and zinc. As for all infants, for the first 4 to 6 months, vegetarian infants should solely receive breast milk or a commercial infant formula. Fortified infant cereal or firm tofu is an appropriate first complementary food. Either of these, along with breast milk or formula, can meet needs for protein, iron, and zinc. Additional foods are introduced with timing similar to that for nonvegetarians. A variety of nutrient-dense foods should be introduced by 1 year of age. Fortified soy or cow’s milk should be the primary beverage postweaning. Growth should be monitored, and toddlers should be served a diet that includes high-calorie, low-fiber foods if growth appears to be faltering. Practitioners can play important roles in assessing the growth of vegetarian infants and toddlers, helping families make appropriate feeding choices, evaluating the need for supplements, and assisting with planning meals that will meet the needs of infants and toddlers.