Low Zinc Concentrations Research Articles

Low Serum Zinc Levels and Associated Risk Factors in Hospitalized Patients Receiving Oral or Enteral Nutrition: A Case-control Study

PurposeTo assess whether hospitalization and feeding strategy impact the risk of hypozincemia and associated risk factors. MethodsIn this case–control study, serum zinc levels were compared between inpatients fed oral nutrition (ON) (n = 76) or enteral nutrition (EN) (n = 191) with outpatient controls (n = 1095). FindingsZinc levels were significantly lower in inpatients receiving EN compared with those receiving ON (P = 0.001). Significant (P < 0.001) β-values of −11.16 and −17.58 for serum zinc concentrations were found for inpatients receiving ON or EN, respectively, compared with the outpatients. Hospitalization and old age were both independent predictors of zinc deficiency. More than 75% of patients >60 years of age fed EN had a zinc concentration <68.75 μg/dL. Low hemoglobin levels increased the risk of low zinc levels for inpatients receiving EN (P = 0.003) and ON (P = 0.026). Age (P < 0.001), noninvasive mechanical ventilatory support (P = 0.016), and critical care (P = 0.018) were risk factors for hypozincemia in patients receiving ON. Low iron levels were associated with hypozincemia (P = 0.001) in patients receiving EN. ImplicationsHospitalization and being >60 years of age were risk factors for zinc deficiency. Intensive care and noninvasive mechanical ventilatory support were risk factors for hypozincemia in hospitalized patients who were fed orally. Low hemoglobin levels increased the risk of low zinc concentrations for inpatients receiving EN and ON, and low iron levels were associated with hypozincemia only after EN.

Effect of long-term fertilization of the permanent dry meadow on the zinc content in soil and meadow sward

The study took place between 2012 and 2014 in Falenty near Warsaw, Poland, as part of a long-term scientific experi-ment (first began in 1987) using the randomized block method. All blocks were irrigated until 2008. In 2009 each block was divided into two areas: irrigated and non-irrigated. The study involved four levels of inorganic nitrogen fertilizer and two levels of mixed inorganic and organic fertilizer in the form of fermented cattle urine. The soil in all experimental plots was characterized by low levels of zinc, ranging from 7.6 to 16.7 mg Zn∙kg–1 dry matter. Much lower Zn content in both soil layers of all irrigated plots was associated with increased yields on these plots, regardless of the level and form of ferti-lizer. The content of Zn in soil and sward in 2014 year was significantly lower compared in 2012. Inadequate levels of zinc for ruminant nutrition were observed in the sward from all plots (15.4–28.8 mg∙kg–1 dry matter). The higher content of zinc was found in sward harvested from the plot, which was not fertilized with phosphorus. The long-term inorganic and fer-mented urine fertilization resulted in very low zinc content in the soil and meadow sward.

Comparative Assessment of Trace Elements in the Blood of Gastric Cancer Patients and Healthy Subjects

Gastric cancer (GC) remains one of the most common malignancies globally, particularly in developing countries. Environmental contaminants such as trace elements are known to involve in a plethora of diseases, including cancer. The present study was carried out to find out the imbalances in trace elemental levels (Cd, Cr, Cu, Fe, Mn, Pb, and Zn) in the blood of GC patients in comparison with and healthy donors. The blood samples were digested in a nitric acid-perchloric acid mixture. The elemental levels were quantified by flame atomic absorption spectrometry. Significantly lower concentrations of zinc, iron, lead, cadmium, and chromium were found in the blood of GC patients than the controls. A correlation study revealed diverse relationships among the elements in the blood of cancerous patients and controls. Considerable variations in the elemental concentrations were observed with the gender, food habits, habitat, and smoking habits of the donors. Elemental contents revealed significant differences with the stages (I, II, III &amp; IV) and types (adenocarcinoma &amp; gastrointestinal stromal tumor) of GC patients. Multivariate analysis exhibited significantly divergent apportionment of the patients' elemental levels and healthy subjects, which may be linked with the altered metabolism of the elements in GC patients.

STUDY OF ALLELIC VARIATION AT GENOME WIDE SSR LOCI IN PARENTS OF MAPPING POPULATION FOR HIGH GRAIN ZINC IN RICE (Oryza sativa L.)

Rice (Oryza sativa L.) is the source of energy and nutrition for more than half of the world’s population hence it is a crop of global significance. Breeding of mineral dense rice varieties is the main target of biofortification strategy to address micronutrient malnutrition globally. Landraces and local genotypes are proven sources of novel alleles and are a promising donor for high grain mineral. A parental polymorphism survey is a prerequisite of any QTL mapping experiment. Present study consisting of SSR markers based parental polymorphism survey at IRRI South Asia Hub ICRISAT, Hyderabad. Parents of mapping population viz Rajendrakasturi (short grain aromatic rice variety with low grain zinc content) and URG-30 (a local genotype from Eastern Uttar Pradesh with high grain zinc content) were screened with 1013 microsatellite markers covering the entire length of all 12 chromosomes to study allelic variation at genome-wide SSR loci. The geographical diverse origin of parents is reflected in genotypic variations in terms of polymorphism. Out of 1013 whole genome wide SSR markers screened, 294 were found to be polymorphic which resulted in 29.02% polymorphism between the two parents. The highest polymorphism was observed with chromosome 4 (40.96%) whereas the lowest polymorphism was observed in chromosome 9 (16%). Based on the outcomes of the present study, a set of genome-wide polymorphic SSRs will be selected for genotyping of mapping population, preparation of linkage map and QTL analysis for high grain zinc content, iron content, grain quality and yield traits.

Assessing metal contaminants in Antarctic soils using diffusive gradients in thin-films

Metal contaminants in Antarctic soils are typically found around research stations which are concentrated in ice-free coastal areas. The risk of these contaminants to the Antarctic environment is not well understood, given Antarctica’s unique organisms and climate. This study assessed the use of diffusive gradients in thin-films (DGT), a passive sampler that measures fluxes of labile metals from soils to porewaters, in Antarctic soils. DGT-labile measurements were compared to three chemical extractants of increasing strength including high-purity water, dilute acid (1 M HCl), and concentrated acids (3:1 v/v HNO3:HCl), to understand differences in contaminant geochemistry that may affect environmental risk. One site had high lead concentrations measured with dilute (114 ± 4 mg kg−1) and concentrated (150 ± 10 mg kg−1) acids, while DGT-labile concentrations were below the method detection limit (0.5 μg L−1), indicating that the lead species has low solubility or lability. Another site had low concentrations of zinc measured by dilute (36.2 ± 0.5 mg kg−1) or concentrated (76 ± 6 mg kg−1) acid extracts, but had high DGT-labile concentrations (350 ± 80 μg L−1). This reflects an active source of zinc supplied from soil to pore water over time. Copper was found to be acid extractable, water-soluble, and DGT-labile, with DGT-labile concentrations of up to 12 μg L−1. Despite the soil and metal-specific geochemical differences, any of the extracts could be used with statistical clustering techniques to identify differences in sites with elevated metal concentrations. This study shows that the DGT-method can identify contaminated sites comparably to chemical extracts but provides environmentally relevant measurements of metal contaminant lability in Antarctic soils.

The Role of Zinc in Copper Homeostasis of Aspergillus fumigatus.

Copper is an essential metal ion that performs many physiological functions in living organisms. Deletion of Afmac1, which is a copper-responsive transcriptional activator in A. fumigatus, results in a growth defect on aspergillus minimal medium (AMM). Interestingly, we found that zinc starvation suppressed the growth defect of the Δafmac1 strain on AMM. In addition, the growth defect of the Δafmac1 strain was recovered by copper supplementation or introduction of the CtrC gene into the Δafmac1 strain. However, chelation of copper by addition of BCS to AMM failed to recover the growth defect of the Δafmac1 strain. Through Northern blot analysis, we found that zinc starvation upregulated CtrC and CtrA2, which encode membrane copper transporters. Interestingly, we found that the conserved ZafA binding motif 5′-CAA(G)GGT-3′ was present in the upstream region of CtrC and CtrA2 and that mutation of the binding motif led to failure of ZafA binding to the upstream region of CtrC and upregulation of CtrC expression under zinc starvation. Furthermore, the binding activity of ZafA to the upstream region of CtrC was inversely proportional to the zinc concentration, and copper inhibited the binding of ZafA to the upstream region of CtrC under a low zinc concentration. Taken together, these results suggest that ZafA upregulates copper metabolism by binding to the ZafA binding motif in the CtrC promoter region under low zinc concentration, thus regulating copper homeostasis. Furthermore, we found that copper and zinc interact in cells to maintain metal homeostasis.

Block Wise Spatial Distribution and Mapping of Cationic Micronutrients in Soils of Jhargram District of West Bengal

Aims: This investigation is aimed to conduct a delineation study to know the spatial distribution of available cationic micronutrients (Zn, Cu, Fe and Mn) in red and lateritic soils of Jhargram district of West Bengal and their relationship with soil chemical properties.&#x0D; Study Design: Spatial distribution.&#x0D; Place and Duration of Study: Geo-referenced 253 surface soil (0-15 cm depth) samples were collected from eight blocks (Gopiballavpur- 1, Gopiballavpur- 2, Nayagram, Jhargram, Sankrail, Jambani, Binpur- 2 and Binpur- 1) of Jhargram district of West Bengal, India during 2017- 2018.&#x0D; Methodology: Grid based detailed block wise soil sampling has been carried out in long term crop growing fields of Jhargram district of West Bengal.The collected soil samples were analyzed and their cationic micronutrient status were depicted through nutrient index and fertility maps. Geographical information system (GIS) is an important tool to identify the risk areas. In our study Arc Info GIS has been used to prepare the spatial distribution maps of available cationic micronutrients and soil chemical properties (pH and organic carbon) of different blocks of this district.&#x0D; Results: The pH, organic carbon content, available Zinc, Copper, Iron and Manganese content in soils were in the range of 3.68-7.6, 0.15-2.01 (%), 0.56-5.52, 2.4-11.76, 31.6-208.4 and 6.32-99.74 mg kg-1, respectively, with the mean value of 4.97,0.64 (%),2.21, 5.75, 114.68 and 41.87 mg kg-1 respectively. The lowest zinc content has been recorded from the soils of Gopiballavpur- 2 block.&#x0D; Conclusion: The calculated NIV and spatial distribution maps clearly indicated that there is no deficiency of Iron, Manganese and Copper in this region. Zinc status did not resemble with other cationic micronutrient status which was mostly low to medium with some patches of deficiencies. Soil pH has significant positive relation with Iron. Copper has significant positive relation with soil organic carbon.

Serum Zinc Concentrations of Adults in an Outpatient Clinic and Risk Factors Associated With Zinc Deficiency

Subclinical features of zinc deficiency can be challenging to recognize. The prevalence of zinc deficiency based on blood zinc concentration in an adult outpatient clinic setting has not been well-studied. To estimate the prevalence of low serum zinc concentrations among community-dwelling adults, and to characterize clinical features and risk factors associated with zinc deficiency. This retrospective pilot prevalence study took place from 2014 to 2017 at an outpatient clinic in southeast Ohio. Patients aged 50 years or older with a stable health status were categorized into a case group with zinc deficiency (serum zinc concentration, <0.66 µg/mL) and a control group (serum zinc concentration, ≥0.66 µg/mL). Measurements included serum zinc concentration, nutritional biomarkers (ie, magnesium, calcium, albumin, and total 25-hydroxy vitamin D levels), patient history of fractures and events such as hospitalization, antibiotic use, and self-reported falls that occurred within 1 year prior to the date serum zinc concentration was measured (index date). Patients were excluded if they had a serum zinc measurement within 2 months after a hospitalization, severe renal insufficiency (3 patients with serum creatinine concentration above 2.5 mg/dL), or serum zinc concentration above 1.20 µg/mL. This study included 157 patients, consisting of a case group of 41 (26%) patients with zinc deficiency and a control group of 116 (74%) without zinc deficiency. Mean (SD) zinc concentrations of the case and control groups were 0.58 (0.05) µg/mL and 0.803 (0.13) µg/mL, respectively (P<.01). Patients in the case group were more likely to have had a history of hospitalization, antibiotic use, a fall within 1 year before the index date, and a history of fractures and hip fracture (P<.01 in each case). Patients taking gastric acid suppressants had increased odds of lower zinc concentrations (odds ratio, 2.24; 95% CI, 1.08-4.63). Both logistic and multivariate linear regression models revealed that past fractures, hip fractures, and hypoalbuminemia (albumin <3.5 g/dL) were associated with zinc deficiency or lower zinc concentrations. This study revealed that 26% of patients in an outpatient adult clinic had zinc deficiency based on serum concentrations. Patients with fracture history and low serum albumin were at higher risk for zinc deficiency.

Materials for the Study of Items from Non-Ferrous and Precious Metals of Selitrennoe Settlement: Chemical Composition

Introduction. This paper presents the results of the study of the chemical composition of nonferrous and precious metal items from the excavations of the Selitrennoe settlement by the Volga Region Archaeological Expedition in 1986–1989 stored in the State Historical Museum. Methods and materials. XRF was used as a method of determining the elemental composition; the main technological operations were determined using the trasology method. A total of 63 subjects were analyzed, including domestic items, jewelry and items related to production. Analysis and Results. The alloys have been distinguished depending on the presence and concentration of alloying elements: brass (two-component, tin, lead, multicomponent), bronzes (tin, lead, leadarsenic, tin-lead, tin-zinc, and multicomponent) and silver alloys (multicomponent high silver bronzes and goldsilver alloy). Inclusions of soldering with silver in the solder and gilding according to the amalgamation have been also recorded. The results of the analysis show the prevalence of two-component brass and multicomponent alloys, a small amount of tin bronzes and the complete absence of items from “pure” metals – copper, tin and lead. The common practice of using recycled metal can be judged by the relatively low content of zinc in brass and a large proportion of multicomponent alloys. Despite the presence of distinguishable stable groups, a wide range of concentrations suggests the absence of clear recipes, including for certain categories of objects. The dependence of the applied technology on the composition of metal is also revealed. The sample of the Selitrennoe settlement is significantly different from other large series of analyses of the Golden Horde time (Bolgar Region, Uvek and its neighborhood).

Elemental composition of soils of the Pur-Taz interfluve

In order to evaluate the chemical composition of natural background environments of Pur-Taz interfluve (Western Siberia), the mineral components of soils, peats, lichens, and sphagnum mosses have been analyzed. The samples were tested using X-ray fluorescence technology. The average contents of hazardous metals in the soils of the Pur-Taz interfluve are either lower (for Cu, Pb, Zn, Ni, Sr) or equal to (for Hg, Co) the average values of these elements in the Earth's crust. This finding corresponds to the commonly held view that the contents of elements in the soils located in the north of Western Siberia are lower than the world averages. Additionally, in our samples low concentrations of copper and zinc have been observed. Since these microelements are important for soil physiology, this finding indicates unfavorable biochemical conditions in the research area. On the other hand, high concentrations are observed for inactive elements such as Mo, Sn and Zr. The significant differences have been identified in the composition of mineral and organic soil horizons. For instance, the average concentrations of P, Zn and S in organic horizons are 7.1, 8.1 and 18 times greater than in the illuvial mineral horizons, respectively. The intense accumulation of Zn, Cu, Cd, Hg has been recorded, all of them are chalcophiles in the ombrotrophic peat. This means that the chemical composition of soil is largely determined by biological accumulation of chalcophile elements. The content of lithophilic Al, Si, Ti and Zr, coming with dust precipitation from the atmosphere increases in the peat of dwarf shrub-moss-lichen tundras and larch woodlands. The revealed values of the elemental composition of soils can be recommended as background in the course of the environmental monitoring.

Çinko Dozlarının Kişniş (Coriandrum sativum L.) Bitkisinin Verim ve Kalitesine Etkisi

Bu araştırmada, çinko dozlarının kişniş (Coriandrum sativum L.) bitkisinin verim ve bazı kalite parametrelerine etkisinin ortaya konulması amaçlanmıştır. Araştırma, Siirt ekolojik koşullarında 2019-2020 vejetasyon döneminde yürütülmüştür. Çalışmada, çinkolu gübrenin (Zn0= 0 kg da-1 Zn, Zn1= 0.5 kg da-1 Zn, Zn2= 1 kg da-1 Zn, Zn3= 1.5 kg da-1 Zn, Zn4 =2 kg da-1 Zn) 5 farklı dozu faktör olarak ele alınmıştır. Araştırma sonuçlarına göre, çinko dozlarının kişniş bitkisinin tohum verimi, verime etkili bazı tarımsal özellikleri ile uçucu yağ oranı ve uçucu yağ verimi üzerine anlamlı etkilerinin olduğu belirlenmiştir. Araştırmada en yüksek; dal sayısı, ana şemsiyede şemsiyecik sayısı, tohum verimi, uçucu yağ oranı ve uçucu yağ verimi Zn3 dozunda saptanmıştır. En yüksek bitki boyu ve bin tane ağırlığı değerleri, Zn3 ve Zn4 çinko dozlarında belirlenmiştir. En yüksek ana şemsiyede tohum sayısı ise Zn2 ve Zn3 çinko dozlarında tespit edilmiştir. Çinko dozlarına göre bitki boyu 68.25-84.00 cm, dal sayısı 4.98-6.19 adet bitki-1, ana şemsiyede şemsiyecik sayısı 5.83-7.08 adet, ana şemsiyede tohum sayısı 37.28-45.73 adet, tohum verimi 103.09-173.45 kg da-1, bin tane ağırlığı 9.95-10.87 g, uçucu yağ oranı % 0.30-0.35, uçucu yağ verimi 0.31-0.61 L da-1 arasında değişim göstermiştir. Çinko içeriği düşük topraklarda, kişniş yetiştiriciliğinde tohum verimi yönünden 1.33 kg da-1 çinko uygulanabileceği sonucuna varılmıştır.

Zinc-Induced Biochemical Constituents and Reproductive Yield of Wheat with Zinc Supply in Sand Culture Conditions

In a sand culture experiment, the present study deals with the quantitative (growth and some biochemical constituents) and qualitative yield of grains (zinc and protein contents) of wheat (Triticum aestivum L., var. HD-2967) under the influence of various concentrations of zinc supply (0.01, 0.1 1.0 and 5 mg l-1). Zinc levels were prepared in a standard nutrient solution (omitting zinc). The zinc accumulation was dose dependent in vegetative parts of wheat, which was increased with increase in zinc supply levels. The low and high zinc content in wheat shoot inhibited pigments content and activity of antioxidative enzymes like catalase and peroxidase. The mobilization of zinc in grains was lower at elevated and low zinc-supply levels in contrast to their accumulation in vegetative parts. The zinc mobilization efficiency index (ZnMEI) was higher at normal doses of zinc as compared to low (0.01 mg l-1) and elevated zinc levels (5 mg l-1). In the present study, maximum increase of 15, 25 and 18% was observed in the dry matter yield, shoot length and total chlorophyll content, respectively following exposure of 1.0 mg l-1 of zinc. At this zinc treatment, protein content in the seeds was elevated by 10% with zinc enrichment by 73%. The observations of this study may be helpful in the studies of zinc-enrichment in wheat production in Zn-deficient soil.

P0940CLINICAL ASSOCIATION BETWEEN SEVERE INFECTION AND HYPOZINCEMIA IN INCIDENT PATIENTS ON HEMODIALYSIS

Abstract Background and Aims Hypozincemia can arise in patients with advanced chronic kidney disease (CKD) due to low protein intake and urinary or dialytic loss. Several studies have confirmed an association between hypozincemia and infection. Because infections comprise a major complication in patients with advanced CKD, we investigated whether hypozincemia is associated with infection risk in incident patients on dialysis. Method We prospectively analyzed 380 consecutive patients aged 20 years old or more who started hemodialysis between January 2013 and December 2018. Six patients who were receiving zinc supplementation at the time of the study were excluded. Serum zinc values were obtained at the time of dialysis initiation. We followed up the remaining patients after enrollment. The endpoint was severe infection defined as infection-related death or bacteremia confirmed by the detection of microorganisms in two sets of culture bottles. The patients were equally divided into groups with low, middle or high serum zinc concentrations. Data were analyzed using Kaplan-Meier curves and Cox hazards models. The local ethics committee approved this research. Informed consent was obtained from each individual participant included in the study. Results The rate of severe infection events over a follow-up of one year was the highest in the group with low zinc (p = 0.030). Cox hazards models adjusted for age, sex, diabetes mellitus, serum albumin and serum zinc, selected hypozincemia as an independent risk factor for severe infection events (HR, 10.76; 95% CI, 1.28–90.41; p = 0.029). Conclusion Hypozincemia is associated with risk of subsequent severe infection in incident patients on dialysis.

Considerations on the Influence of Zinc on Infectious Diseases in Children

Zinc modulates the human body defence against infections. Mild and medium deficiency in this mineral appears usually sub-clinically, being mistaken for other diseases, but the severe form can be fatal. The purpose of the study was to determine the plasma zinc concentration (PZC) for the most common infectious pathology in children. Zinc was measured in plasma using direct colorimetric assay based on the 5-Br-PAPS method (CV% 0.98-4.64%). In the paediatric patients, 0-3 years old, the PZC values were 15.20�1.37 μmol/L, with limits ranging between 13.05-20.6 μmol/L, the values falling within normal limits and proving the absence of zinc deficiency in the investigated population. During 3 years of follow up, 137 healthy children presented low values of plasma zinc concentration if they had acute lower respiratory infections, acute otitis media or giardiasis in past medical history. There were not found significant differences in case of children with viral or bacterial acute diarrheal diseases or viral exanthemas. In the present study, the children exposed to severe, complicated or chronic forms of infectious diseases were predisposed to low plasma zinc concentrations.

The metabolic function of the metal transporter SLC39A14

Microelement is one of the nutritional elements of the human body. They participate in a wide range of physiological and biochemical functions of the human body, such as electron transport, oxygen delivery, enzyme activity, and cell growth and differentiation, etc. They also could be used as auxiliary components of biological macromolecules, or as the functional components of hormones and vitamins, which are of great significance to maintain life activities. Among them, essential trace elements, such as iron, zinc, and manganese, are not produced or synthesized in the body, but indispensable to maintain the whole-body physiological function. Essential trace elements are absorbed and transported into the blood circulation by a variety of metal transporters in the upper digest tract. Recently, with the identification and discovery of metal transporters and multifunctional study, we gain an in-depth understanding of metal transporters in metabolic organs and various metabolic diseases. Solute carrier 39 (SLC39), also known as zinc importer protein (ZIP) family, is a metal importer. According to the homology analysis of gene sequence, this family has 14 members, SLC39A1–SLC39A14 (ZIP1–ZIP14). Based on the protein structure, ZIP family could be divided into four subfamilies: I, II, Gufa, and LIV-1. SLC39A14 belongs to the LIV-1 subfamily of ZIP zinc transporters (LZT) family. It has 8 transmembrane domains (TM), histidine-rich domains and a conserved “HEXHEXGD” fragment. SLC39A14 is mainly expressed on the cellular membrane. Recent studies have demonstrated that it is involved in the absorption of metals like zinc, iron, and manganese in different metabolic tissues or organs. The function of SLC39A14 was investigated by generating global or tissue-specific knockout mice in different metabolic organs such as the liver, pancreas, adipose, and skeletal muscle. Most of these studies indicate that Slc39a14 -deletion may perturb tissue metabolic functions, such as insulin synthesis and secretion, disrupted insulin sensitivity or tissue metal absorption. More specifically, for the Slc39a14 global knockout mice ( Slc39a14-KO ), the insulin sensitivity and adipocyte differentiation are impaired in adipose tissue. Slc39a14-KO also disrupts gluconeogenesis in hepatic tissue induced by low tissue zinc content. Meanwhile, hepatocyte-specific knockout of Slc39a14 shows that SLC39A14 may be involved in hepatic manganese transportation and non-transferrin-bound iron (NTBI). In the mouse β cell line (Min6), SLC39A14 is involved in the endocrinal function of the pancreas, especially the insulin synthesis and secretion function in β cell. Furthermore, SLC39A14 function in skeletal muscle and myoblast suggests that SLC39A14 may regulate tissue zinc homeostasis in skeletal muscle of tumor metastasis animal model. In C2C12 myoblasts, SLC39A14 participates in myogenic differentiation and myotube development. In addition, the expression of SLC39A14 is not only regulated by the concentration of trace elements in blood circulation and intake level of elements from diets but also regulated by inflammatory factors such as LPS and IL-6. In this review, the metabolic function of metal transporters SLC39A14 in different tissues and organs is summarized.

A Comparative Study of Heavy Metals and Trace Elements Concentration in Milk Samples Consumed in Iraq

The measurements of major and trace elements in different brands of milk powder selected from the Iraqis market via the X-ray fluorescence (XRF) Technique have been studied in the present work. The result of the measurements reveals the high concentrations of sodium, phosphorus, sulfur, chlorine, potassium, calcium and magnesium. Furthermore, low concentrations of aluminum, silicon, iron, bromine, molybdenum, iodine, barium, titanium, manganese, cobalt, chrome, nickel, copper, zinc and lead were detected. Neutron activation analysis (NAA) and Kjeldahl technique were also employed to determine the concentrations of nitrogen. It was found that the nitrogen concentration was in the range of (1.96 - 3.23) % which is within the permissible limits. The concentrations of the trace elements (copper, manganese, zinc, lead) were verified via the atomic absorption spectrometer (AAS) technique. The results are compared with the authorized limit by the food and agriculture organization and the world health organization (FAO/WHO) standards.

Immobilization of Chromium in Stainless Steel Slag Using Low Zinc Electric Arc Furnace Dusts

A new synergistic treatment of stainless steel slag and low zinc content electric arc furnace (EAF) dusts is proposed to immobilize harmful chromium in stainless steel slag. The effects of ZnFe2O4 addition on the mineralogic phase and chromium leachability of CaO-SiO2-MgO-Al2O3-Cr2O3 synthetic slag were investigated to explore the feasibility of this method. The mineralogic phases in stainless steel slag were investigated by scanning microscopy equipped with energy-dispersive spectroscopy and X-ray diffraction. The leaching concentration values of chromium and zinc were evaluated according to an alkaline digestion for the hexavalent chromium (US-EPA-3060A) and toxicity characteristic leaching procedure (TCLP, US-EPA-1311) method, respectively. It was found that all synthetic slags mainly contain α-Ca2SiO4, merwinite and spinel phase, in line with the calculation results by FactSage. The crystallization of spinel and merwinite phases was enhanced by the addition of ZnFe2O4 but suppressed the precipitation of α-Ca2SiO4. It was revealed that the leaching concentration of chromium was depressed by adding ZnFe2O4 and was far below the chemical limits defined in the French proposal for a criterion and evaluation methods for waste ecotoxicity (0.1 mg L−1). In addition, the zinc leaching concentration meets the sanitary landfill standard. The proposed synergistic treatment method was further validated on industrial stainless steel slags and EAF dusts. Experimental results indicated that the synergistic treatment method can immobilize chromium effectively and the final slags can be disposed of by sanitary landfilling or recycling as constructional materials. A schematic technologic route diagram of the synergistic treatment was also proposed.

Low serum zinc concentrations in Sudanese patients with visceral leishmaniosis does not impair the anti-Leishmania antibody response.

Visceral leishmaniosis (VL) is a poverty-related disease, affecting poor peoples in the developing countries. For unknown reasons, the rK39 rapid test has poor diagnostic sensitivity in some endemic areas such as East Africa. Here, the hypothesis was tested whether micronutrient deficiency is associated with low Leishmania-specific antibody responses and consequently decreased diagnostic sensitivity. Serum zinc concentrations in 107 human sera of VL and controls that were HIV-negative were measured using atomic absorption spectroscopy. Anti-Leishmania donovani antibodies were detected quantitatively by rKLO8 ELISA. The influence of low serum zinc concentrations on the amount of anti-Leishmania antibody and outcome of the rK39 rapid test was tested. Serum zinc concentrations were significantly (p ˂ 0.0001) reduced in VL sera (mean 0.41 ± 0.15) as compared to healthy control groups (mean ˃ 0.75 ± 0.13). Interestingly, the majority (92.2%) of the VL patients had low serum zinc concentrations (˂ 0.6 mg/l) whereas all healthy controls showed normal levels. Unexpectedly, VL sera with normal (0.94-0.6 mg/l) or low (˂ 0.6 mg/l) zinc concentrations demonstrated no significant difference in amounts of Leishmania antibodies. In addition, VL sera with positive or negative rK39 rapid test results demonstrated similar serum zinc concentrations; mean values of 0.39 ± 0.14 mg/l and 0.38 ± 0.1 mg/l for VL sera of positive or negative rK39 results, respectively. Low serum zinc concentration seems not to play an important role in lowering anti-L. donovani antibody titers observed among Sudanese VL patients and doesn't affect rK39 rapid test results.

Importance of micronutrients (Zinc) in crop production: A review

Micro nutrients are designed to supply critically needed nutrients at the most responsive time during the growth cycle and to stimulate and optimize the assimilation and production process in the leaves. Micronutrients are the elements which are essential for the plant growth when roots are unable to absorb sufficient nutrients from soil due to high degree of fixation, losses from leaching, low soil temperature and lack of soil moisture. Zinc (Zn) is one of the eight essential micronutrients. It is needed by plants in small amounts, but yet crucial to plant development. In plants, zinc is a key constituent of many enzymes and proteins. It plays an important role in a wide range of processes, such as growth hormone production and internode elongation. Crop yield significantly increases with the use of micronutrients such as zinc (Zn), iron (Fe), boron (B), copper (Cu), manganese (Mn), etc. Zinc (Zn) has an important metabolically role in plants growth and development and is therefore called an essential trace element or a micronutrient. Zinc is uptake and transfers the form of Zn 2+ in plants and is an essential nutrient that has particular physiological functions in all living systems, such as the maintenance of structural and functional integrity of biological membranes and facilitation of protein synthesis and gene expression, enzymes structure, energy production and Krebs cycle; also has a positive impact on crops yield; therefore crops quantitative and qualitative yield is strongly dependent on zinc (Zn) in the soil. Calcareous soils with high intake of phosphorus (P) and soils with high pH are confronted with zinc deficiency. Zinc is an active element in biochemical processes and there is chemical and biological interaction between it and some other elements such as phosphorus, iron and nitrogen in plants. Phosphorus and copper have an antagonistic impact on zinc. The Food and Agriculture Organization (FAO) has determined that zinc is the most commonly deficient micronutrient in agricultural soils; almost 50% of agricultural soils are Zn deficient. Plants growing on potentially zinc-deficient soils have reduced productivity and contain very low concentrations of zinc in the edible parts (such as in cereal grains). Therefore, zinc deficiency represents a serious nutritional and health problem in human populations, especially in the developing world where cereal-based foods are the dominating source of diet. Hence, the review.

FOLIAR FEEDING WITH ZINC AS A BIOFORTIFICATION STRATEGY IN MAIZE

Human zinc malnutrition is a concern in the contemporary scenario. Ranked among the serious micronutrient deficiencies and considered a major cause of child mortality, especially in developing countries. Cereals, such as maize (Zea mays L.), food source in these countries, show low zinc concentration. In view of this, biofortification has been shown promise to increase the nutrient content in staple foods and to improve their nutritional quality. The aim of this study was to evaluate the potential of maize genotypes in relation to yield and zinc concentration in grains and leaves as a function of zinc sulfate doses in two growing seasons. A total of 17 commercial hybrids were evaluated in three doses (0, 5, and 10g L-1 ha-1). The zinc concentration was quantified by acid digestion, followed by atomic absorption spectrophotometer analysis. Any change was observed in grain yield as a function of the doses. Higher doses applied near flowering resulted in higher concentrations of the micronutrient in the grains. However, the concentrations in the grains were, on average, below the value established by the Harvest Plus biofortification program. The results provide information for the selection of genotypes with zinc uptake potential aiming at food safety through agronomic biofortification.