Zinc Retention Research Articles

Effects of cooking methods on the iron and zinc contents in cowpea (Vigna unguiculata) to combat nutritional deficiencies in Brazil

BackgroundBecause iron deficiency anemia is prevalent in developing countries, determining the levels of iron and zinc in beans, the second most consumed staple food in Brazil, is essential, especially for the low-income people who experience a deficiency of these minerals in their diet.ObjectivesThis study aimed to evaluate the effect of cooking methods by measuring the iron and zinc contents in cowpea cultivars before and after soaking to determine the retention of these minerals.MethodsThe samples were cooked in both regular pans and pressure cookers with and without previous soaking. Mineral analyses were carried out by Spectrometry of Inductively Coupled Plasma (ICP).ResultsThe results showed high contents of iron and zinc in raw samples as well as in cooked ones, with the use of regular pan resulting in greater percentage of iron retention and the use of pressure cooker ensuring higher retention of zinc.ConclusionsThe best retention of iron was found in the BRS Aracê cultivar prepared in a regular pan with previous soaking. This cultivar may be indicated for cultivation and human consumption. The best retention of zinc was found for the BRS Tumucumaque cultivar prepared in a pressure cooker without previous soaking.

Advanced dextran based nanogels for fighting Staphylococcus aureus infections by sustained zinc release.

The growth in numbers and severity of hospital acquired infections has increased the need to target bacteria locally and specifically. Consequently, smart drug-delivery systems are being developed for local bactericidal action. The approach takes the concept of nanogels in drug delivery of small molecules to the next level by enclosing them in a shell. Versatile polysaccharide nanogels were loaded with zinc ions as antibacterial agents in a miniemulsion process, in order to target methicillin resistant strains of Staphylococcus aureus (MRSA). The encapsulation of drugs in nanogels is limited by the crosslinking density of the gel and the size of the drug. The characterization of the nanogels with inductively coupled plasma optical emission spectroscopy (ICP-OES) revealed that zinc ions cannot be retained within without an additional 'shell' layer. The nanogels were surrounded by a dextran-polyurethane shell, which can retain substances by reduction of water penetration. A delayed zinc release compared to the nanogels was confirmed by ICP-OES. Bacterial tests revealed an antibacterial effect of the shell enhanced nanogels against S. aureus. The studied nanogel system shows potential in locally addressing bacterial infections. The platform is extremely versatile and can be tailored to application as dextran and Zn(NO3)2 can be replaced by other polysaccharides (e.g. hyaluronic acid) and antibacterial agents, respectively.

Composite Material with Calcium Sulfate and Calcium Phosphate for Heavy Metals Retention

Porous composite materials containing calcium phosphate and calcium sulphate were elaborated by mixing various hydroxyapatites with calcium sulphate hemihydrate, adding water and moulding the paste into shape. The composite material was broken into small granules of 5mm size to test for heavy metal retention in a column configuration. It was found that the amount of zinc ions retained depended on the contents in apatites present in the composite, and that results were similar to the results obtained for equivalent amounts of pure apatite put in the same column. These results are interesting because previous work on pure apatites showed release of small sub-micrometer sized metal phosphates when the apatite particles were contacted with heavy metals in a flow-through experiment. Thus, the plaster matrix does not prevent metal uptake from aqueous solutions and helps minimize release of fines from the used apatite. The breakthrough curves and zinc retention capacities will be presented for various composite compositions, flow rates and zinc concentrations.

Copper and Zinc removal from aqueous solutions by polyacrylic acid assisted-ultrafiltration

Copper and Zinc removal from aqueous solution by polyelectrolyte enhanced ultrafiltration (PEUF) process was investigated using poly(acrylic acid) (PAA) with average molecular weight 100kDa. The ultrafiltration studies were carried out using a tangential cell system, equipped with 10,000 MWCO regenerated cellulose. Several parameters have been studied such as: transmembrane pressure, PAA concentration, pH and ionic strength to improve the retention of the metal ions. The removal of Zn2+ and Cu2+ is respectively more than 70% and 93%. A better retention was observed at 2·10−3molL−1 PAA concentration and 3bar transmembrane pressure. The pH effect on the Zinc and Copper recovery revealed a maximum retention around 75% and 97%, respectively, for pH=5. The study of the ionic strength effect has shown a retention decrease with the salt concentration increase. Selectivity was studied using a solution containing the two metal ions. Zinc retention decreases compared to single metal solutions, and this is more significant in the case of Copper ions.

Zinc and copper requirements in preterm infants: An examination of the current literature

BackgroundZinc and copper are essential for preterm infants, but recommended requirements from different groups vary widely. Recommended zinc intakes have steadily increased over the years. Although this would be expected to impair copper absorption, recommended copper intakes have not risen in parallel. ObjectivesTo systematically review the literature on zinc and copper retention in preterm infants; to examine the effect on zinc intake on copper retention; and to estimate the zinc and copper intakes required to meet the levels of zinc and copper retention required for normal growth. DesignStudies reporting zinc and/or copper retention in preterm infants (<36weeks of gestation) during the first 120days of life were identified using PubMed. Only studies reporting net retention were included. ResultsFourteen studies on zinc retention reporting data on 45 different groups were identified. Eleven studies (32 groups) were identified reporting copper retention. Zinc retention was significantly higher at higher zinc intakes, and higher in formula-based diets than in human milk based diets. Zinc intakes of between 1.8–2.4mg/kg/d (from formula based diets) and 2.3–2.4mg/kg/d (from human-milk based diets) were required to achieve adequate zinc retention. Copper retention was significantly positively correlated with copper intake and significantly negatively correlated with zinc intake. At the zinc intakes suggested previously (1.8–2.4, 2.3–2.4mg/kg/d), copper intakes of between 200 and 250mcg/kg/d are required to ensure adequate copper retention. ConclusionsOur results support the higher zinc intakes recommended in recent guidelines. However, they suggest that recommended copper intakes have not kept pace with increasing zinc intakes, and that preterm infants may need higher copper intakes than currently recommended.

The interactive effect of cobalt enrichment in Artemia on the survival and larval growth of barramundi, Lates calcarifer

Cobalt is a naturally occurring element in the aquatic environment and is essential for many living functions of vertebrates. The role, retention and interactions of cobalt with other trace elements in the marine fish nutrition have been poorly documented. In this study the accumulation and effect of cobalt was investigated on the survival and larval growth of barramundi, Lates calcarifer, when fed individually and combined with zinc and manganese through a nourishment organism. Barramundi larvae from 14 to 30dph were fed with Artemia nauplii in nine treatments (n=3): without enrichment (control), enriched with 50mgL−1 and 100mgL−1 CoCl2 (Co-1 and Co-2), MnCl2 (Mn-1 and Mn-2), CoCl2 along with MnCl2 (CoMn-1 and CoMn-2) as well as CoCl2 along with ZnSO4 (CoZn-1 and CoZn-2) respectively. All treatments had significant effect on the cobalt, manganese and zinc level of Artemia. The concentration of these elements increased in parallel with the dose of supplementations. Our results show that a significantly higher growth performance of barramundi larvae can be achieved when cobalt and manganese supplementation is applied. No interaction occurred between the retention of zinc and cobalt, but a competitive type of interaction is assumed between the deposition of cobalt and manganese in barramundi larvae. Combined treatments of cobalt and manganese increased cannibalism and mortality significantly, while other treatments had no significant effect on the survival of barramundi. Redundancy analysis showed a strong correlation between the cobalt and manganese concentration of Artemia and barramundi larvae, as well as a total agreement between the zinc concentration of the zooplankton and the larvae.

A16 EVALUATION OF THE COST SAVINGS ACHIEVED BY HAVING AMPHOTERICIN B LIPOSOMAL CENTRALIZED COMPOUNDING BY THE PHARMACY DEPARTMENT OF AN ACADEMIC INSTITUTION

Zinc and copper are essential for preterm infants, but recommended requirements from different groups vary widely. Recommended zinc intakes have steadily increased over the years. Although this would be expected to impair copper absorption, recommended copper intakes have not risen in parallel.To systematically review the literature on zinc and copper retention in preterm infants; to examine the effect on zinc intake on copper retention; and to estimate the zinc and copper intakes required to meet the levels of zinc and copper retention required for normal growth.Studies reporting zinc and/or copper retention in preterm infants (< 36 weeks of gestation) during the first 120 days of life were identified using PubMed. Only studies reporting net retention were included.Fourteen studies on zinc retention reporting data on 45 different groups were identified. Eleven studies (32 groups) were identified reporting copper retention. Zinc retention was significantly higher at higher zinc intakes, and higher in formula-based diets than in human milk based diets. Zinc intakes of between 1.8–2.4 mg/kg/d (from formula based diets) and 2.3–2.4 mg/kg/d (from human-milk based diets) were required to achieve adequate zinc retention. Copper retention was significantly positively correlated with copper intake and significantly negatively correlated with zinc intake. At the zinc intakes suggested previously (1.8–2.4, 2.3–2.4 mg/kg/d), copper intakes of between 200 and 250 mcg/kg/d are required to ensure adequate copper retention.Our results support the higher zinc intakes recommended in recent guidelines. However, they suggest that recommended copper intakes have not kept pace with increasing zinc intakes, and that preterm infants may need higher copper intakes than currently recommended.

Zinc and vegetarian diets.

Well planned vegetarian diets can provide adequate amounts of zinc from plant sources. Vegetarians appear to adapt to lower zinc intakes by increased absorption and retention of zinc. Good sources of zinc for vegetarians include whole grains, tofu, tempeh, legumes, nuts and seeds, fortified breakfast cereals and dairy products. The inhibitory effects of phytate on absorption of zinc can be minimised by modern food-processing methods such as soaking, heating, sprouting, fermenting and leavening. Absorption of zinc can be improved by using yeast-based breads and sourdough breads, sprouts, and presoaked legumes. Studies show vegetarians have similar serum zinc concentrations to, and no greater risk of zinc deficiency than, non-vegetarians (despite differences in zinc intake).

Effect of Different Levels of Nanoparticles Chromium Picolinate Supplementation on Performance, Egg Quality, Mineral Retention, and Tissues Minerals Accumulation in Layer Chickens

This study was conducted to investigate the effects of various levels of nanoparticles chromium picolinate on performance, egg quality, minerals retention, and tissues accumulation of layer chickens. This study used 54 seventy-week old post-molt laying hens randomly allocated into 0 (control), 500 ppb (µg kg-1) Cr and 3000 ppb Cr groups for a 60-day experiment. The chromium was nanosize (80.8 ± 2.7 nm) chromium picolinate (NanoCrPic) and each treatment was undertaken with six replicates. In the meantime, a total of 18 birds (1 bird/replicate) were used for metabolic experimentation. The results of the experiment indicated that there were no significant effects on body weight, feed intake, feed efficiency, and egg production of layers. Supplemental NanoCrPic could significantly (p < 0.05) improve egg quality, or retention of chromium and zinc, but decrease shell ratio in the 60th day eggs. The addition of NanoCrPic resulted in increased minerals accumulation in tissues such as Cr, Ca, and P concentration in the liver, Cr concentration in the yolk and Ca concentration in the eggshell. In conclusion, supplemental NanoCrPic improved Cr and Ca accumulation in the liver and egg, improved Zn and Mn retention in layer chickens.

Effect of high energy and/or high protein diets on zinc and copper metabolism in goats

The effect of different levels of energy and protein on the utilization of zinc and copper were evaluated in four metabolic experiments. A total of nine growing castrated male balady kids having nearly the same age (8-9 months) and body weight (15-18kg) were experimented on. Kids were housed individually in metabolism cages in order to collect feces and urine separately. Four experiments, 3 trials per each were done on the same animals, with about 10 days as a rest period between one experiment and another, in which the animals were fed on control ration during the interval. The nine kids were randomly divided into 3 groups (A, B and C), 3 kids per each. The first group (A) was fed the control ration and used as control, while the other two groups (B and C) were fed the tested rations which furnished 15% more or less DE and CP than the control. Feeding the high energy ration increased the apparent absorption and retention of copper and decreased the apparent retention of zinc, while feeding low energy ration decreased the apparent absorption and retention of zinc and copper. Feeding the high protein ration decreased the apparent absorption and retention of copper, while low protein ration increased the absorption and retention of zinc and copper. Feeding the high energy-high protein ration increased the apparent absorption of zinc but decreased the apparent absorption of copper. On the other hand, low energy-low protein ration decreased the absorption and retention of zinc but increased the absorption and retention of copper.

Metabolism Energy, Nitrogen Retention, and Mineral Retention of Phosphorus Calcium and Zinc of Sugarcane Juice in Broilers

Poultry feed derived from grains has an anti-nutrient phytic acid. Naturally, phytate forms a complex bond with some minerals (P, Zn, Fe, Mg, and Ca), protein, and amino acids. The mineral-phytate complex cannot be absorbed by the small intestine of non-ruminant livestock and will adversely affect the availability of minerals in the ration. One way to improve the efficiency of mineral and protein utilization from phytate is using phytase. Sugarcane juice containing nutrients and phytase is very potential as liquid supplement for broiler chickens as it can hydrolyze phytic acid. The purpose of this study was to determine the retention of nitrogen, metabolism energy, and retention of minerals (P, Ca and Zn) of sugarcane juice in broilers. The study was conducted for 7 days using metabolism cages for 28 broilers of 5 weeks old with 6 treatments of 4 replications, 4 for endogenous. The results showed that the administration of 2.5%/kg sugarcane juice in the ration as well as in 2.5%/liter sugarcane juice in drinking water could provide the same result as giving commercial phytase 250-500 FTU/kg on the retention of nitrogen, metabolizeable energy, and retention of minerals P, Ca and Zn.

Iron and zinc bioavailability in Caco-2 cells: Influence of caseinophosphopeptides

A study has been made of the influence of two pools of caseinophosphopeptides (CPPs) obtained from αs- and β-casein (CN) fractions, and of three specific CPPs (β-CN(1–25)4P, αs1-CN(64–74)4P and αs2-CN(1–19)4P), on iron bioavailability (ferritin synthesis) and zinc bioavailability (retention, transport and uptake of zinc) in Caco-2 cells.α-CPP and β-CPP pools did not improve ferritin synthesis, but the three specific CPPs showed an increase in ferritin synthesis in Caco-2 cells versus iron sulphate, β-CN(1–25)4P being the most effective. In relation to zinc bioavailability, α-CPPs, β-CPPs, αs1-CN(64–74)4P and β-CN(1–25)4P increased zinc uptake. However, this increase was of the same order as the increase due to the presence of zinc sulphate.

Inertisation of galvanic sludge with calcium oxide, activated carbon, and phosphoric acid

In this study we compared three methods for the treatment of electroplating sludge highly loaded with zinc and iron: (1) calcium oxide-based solidification/stabilisation; (2) conversion into inert material by adsorption of organic and inorganic pollutants onto activated carbon; and (3) conversion of mobile waste components into insoluble phosphates. All three methods proved highly efficient in the conversion of hazardous waste into inert material. Under optimum treatment conditions zinc concentration in the leachate of solidified waste was reduced by 99.7 % compared to untreated sludge. Zinc retention efficiency in the waste treated with activated carbon and phosphoric acid was 99.9 % and 98.7 %, respectively. The advantages of electroplating sludge treatment with activated carbon over the other two methods are high sorption capacity, insignificant pH and volume changes of the sludge, and simple use.

Zinc nutrition from discovery to global health impact.

Zinc nutrition from discovery to global health impact.

The Effect of r-irradiation and Cooking on the Physicochemical Properties of African Oil Bean Seed (Pentaclethra macrophylla benth) and Its Oil Extract

Irradiation is a potentially useful technology for ensuring the safety and extending the shelf-life of food products. The effects of r-irradiation (5kGy, 10kGy), cooking and combined treatment of 10 kGy irradiation and cooking on the chemical and functional properties of African oil bean seed (Pentaclethra macrophylla Benth) and physicochemical properties of its oil were investigated. The irradiated seeds and un-irradiated seeds were mechanically dehulled and milled into flour using an attrition mill. ‘Raw seed’, ‘cooked seed’, ‘irradiated (5kGy) seed’, ‘irradiated (10kGy) seed’ and ‘irradiated (10kGy) and cooked seed’ flour samples were analyzed for proximate composition, mineral content, functional properties and antinutritional factors, and the seed oils were analyzed for peroxide value, iodine value, acid value and free fatty acid content. The results show that the combined effect of r-irradiation and cooking gave highest increase in nutritional quality, reducing protein from 32.91g/100g DM in the raw seed to 30.55g/100g DM and increasing fat content from 47.43g/100g DM to 51.19g/100g DM. Combined treatment led to the retention of sodium, calcium, zinc and iron more than the single treatments, but the same process reduced magnesium from 0.52mg/100g to 0.47mg/100g and phosphorus from 0.43mg/100g to 0.35 mg/100g. Least gelation concentration and emulsion capacity increased with combined r-irradiation and cooking, whereas foaming capacity and water absorption capacity decreased significantly (p<0.05). Gamma-irradiation and cooking reduced the concentration of all the antinutritional factors. Combined r-irradiation and cooking increased the peroxide value significantly (p<0.05) from 7.03 mg/g oil to 16.50 mg/g oil and increased the acid value, iodine value and free fatty acid of P. macrophylla seed oil. Combination of r-irradiation and cooking increased nutrient bioavailability in the seed; it led to improvement in the functional properties and increased the susceptibility of the oil to rancidity.

Natural zinc enrichment in peatlands: Biogeochemistry of ZnS formation

Peatlands effectively retain heavy metals and prevent stream and watershed contamination. Sulfate reduction is considered the most significant process of metal immobilization in natural wetlands and microbial sulfate reduction is the presumed mechanism that results in the precipitation of metal sulfides. In this study, we examined the biogeochemical mechanisms involved in zinc retention and accumulation in a metalliferous peatland of western New York. In the reducing conditions of these peatlands zinc sulfides occurred as framboidal aggregates of sphalerite and polytypic wurtzite (2nH, n⩾2) nanocrystallites associated with bacterial cells and organic matter. Bacterial cells were co-located with ZnS inside peat particles where the microenvironment remained anoxic. The peat zinc sulfide was depleted in 34S isotopes relative to the sulfate supplied to the peatland by 18–34 per mill, implicating its biological formation. Extraction of microbial community DNA from peat samples yielded diverse PCR amplicons from dissimilatory sulfite reductase (dsrAB) genes, indicating varied bacterial taxa capable of reducing forms of oxidized sulfur. Nanocrystals with distinct structural features were observed in samples containing contrasting dsrAB sequences. The results of this investigation provide clear evidence that microorganisms can influence the chemical forms of heavy metals in peatland environments. Our findings also provide insight into the conditions necessary to promote the immobilization of chalcophile elements in engineered systems for the treatment of acid mine drainage and wastewater effluents.

Iron and zinc retention in common beans (Phaseolus vulgaris L.) after home cooking

Background: According to the World Health Organization (WHO), iron, iodine, and Vitamin A deficiencies are the most common forms of malnutrition, leading to severe public health consequences. The importance of iron and zinc in human nutrition and the number of children found to be deficient in these nutrients make further studies on retention in cooked grains and cooked bean broth important.Objectives: This work aimed to evaluate iron and zinc retention in six common bean (Phaseolus vulgaris L.) cultivars under the following conditions: raw beans, regular pot cooking, pressure cooking, with and without previous water soaking, and broth.Design: Determination of iron and zinc content in the raw, cooked bean grains and broth samples was carried out by Inductively Coupled Plasma (ICP) Optical Emission Spectrometry (Spectro Analytical Instrument – Spectroflame P). All experiments and analyses were carried out in triplicate.Results: Overall, regardless of the cooking method, with or without previous water soaking, the highest zinc concentration was found in the cooked bean grains. However, pressure cooking and previous water soaking diminished iron retention in the cooked grains, while increasing it in the bean broth.Conclusion: The common bean was confirmed to be an excellent source of iron and zinc for human consumption, and it was suggested that beans should be consumed in a combined form, i.e. grain with bean broth.

Role of Titanium Dioxide Nanoparticles in the Elevated Uptake and Retention of Cadmium and Zinc in Daphnia magna

Titanium dioxide nanoparticles (nano-TiO(2)) are now widely applied in consumer products, and the dispersion of nano-TiO(2) may adsorb metals and modify their behavior and bioavailability in the aquatic environment. In the present study, the aqueous uptake, dietary assimilation efficiency (AE), and efflux rate constant (k(e)) of two toxic metals (cadmium-Cd, and zinc-Zn) adsorbed on nano-TiO(2) in a freshwater zooplankton Daphnia magna were quantified. The biokinetics was then compared to daphnids that were exposed only to dissolved metals as controls. The aqueous uptake of Cd and Zn involved an initial rapid uptake and then an apparent saturation, and the uptake of metals was accompanied by an ingestion of nano-TiO(2). The AEs of Cd and Zn adsorbed on nano-TiO(2) were 24.6 ± 2.4-44.5 ± 3.7% and 30.4 ± 3.4-51.8 ± 5.0%, respectively, and decreased with increasing concentrations of nano-TiO(2). Furthermore, the difference between the AEs of Cd and Zn indicated that the desorption of Cd and Zn from nano-TiO(2) may have occurred within the gut of daphnids. With the use of algae as carrier, the AEs of Cd and Zn adsorbed on nano-TiO(2) were significantly higher than those of Cd and Zn directly from nano-TiO(2). The efflux rate constants of Cd and Zn adsorbed on nano-TiO(2) in the zooplankton were significantly lower than those of Cd and Zn not adsorbed on nano-TiO(2). Our study shows that the uptake and retention of toxic metals is enhanced when they are adsorbed on nano-TiO(2), and suggests more attention be paid to the potential influences of nano-TiO(2) on the bioavailability and toxicity of other contaminants.

The bioavailability of different chemical forms of zinc in fattening lambs

Abstract. The aim of the presented study was an estimation of the zinc bioavailability derived from amino acid complexes with methionine, lysine and glycine in growing lambs. 48 lambs, Polish Merino × Romanowski × Charolaise crossbreed, at age about 10 weeks and average body weight of 20 kg were randomly divided into 4 experimental groups. Animals were kept collectively and fed with concentrate and hay in amount: 0.7–1.2 and 0.3–0.5 kg/day/head, respectively. After rearing period 6 rams from each group with average body weight of about 30 kg were divided into digestibility-balance experiments. At the end of the experiment the blood samples were taken, then from each group 8 lambs were chosen, killed and during dissection tissue samples were taken (liver, pancreas, kidney and rib bone). In tissue samples as well as in fodders and excrements the content of zinc was determined. Obtained data in digestibility experiments allowed on calculation of apparent absorption and retention of zinc and the level of Zn determined in tissues’ samples were used to the estimation of bioavailability of zinc from different ones applied in experiment sources. Apparent absorption and retention of zinc were higher (P≤0.01) in lambs receiving in mixtures amino acid complexes of zinc than in animals from the control group. The higher content of zinc in soft and hard tissues of lambs which received organic forms of zinc might indicate better assimilation and bioavailability of zinc from these forms than from oxide. Among tested organic forms of zinc, the zinc-lysine complex was characterized as having the most advantageous property.

Mycobacterial P1-Type ATPases Mediate Resistance to Zinc Poisoning in Human Macrophages

SummaryMycobacterium tuberculosis thrives within macrophages by residing in phagosomes and preventing them from maturing and fusing with lysosomes. A parallel transcriptional survey of intracellular mycobacteria and their host macrophages revealed signatures of heavy metal poisoning. In particular, mycobacterial genes encoding heavy metal efflux P-type ATPases CtpC, CtpG, and CtpV, and host cell metallothioneins and zinc exporter ZnT1, were induced during infection. Consistent with this pattern of gene modulation, we observed a burst of free zinc inside macrophages, and intraphagosomal zinc accumulation within a few hours postinfection. Zinc exposure led to rapid CtpC induction, and ctpC deficiency caused zinc retention within the mycobacterial cytoplasm, leading to impaired intracellular growth of the bacilli. Thus, the use of P1-type ATPases represents a M. tuberculosis strategy to neutralize the toxic effects of zinc in macrophages. We propose that heavy metal toxicity and its counteraction might represent yet another chapter in the host-microbe arms race.