Total Zn Research Articles

Research Note: Relative bioavailability of zinc in zinc hydroxychloride for chicks

A chick assay was conducted to determine the effects of Zn source on performance and to establish a Zn relative bioavailability value (RBV) for a new source of Zn hydroxychloride. In the assay, 8-day-old chicks were fed a Zn-deficient soy protein concentrate diet supplemented with 0, 7, and 15 mg Zn/kg from feed grade ZnSO4 monohydrate for 14 d to establish a standard response curve. The same basal diet was supplemented with 3, 7, and 10 mg Zn/kg from a new Zn hydroxychloride (SAMZn). A second source of Zn hydroxychloride (IBZn) was supplemented at 10 mg Zn/kg as a direct comparison to the highest level of SAMZn. Weight gain increased (P < 0.05) with increasing Zn level, regardless of source. Weight gain of chicks fed 7 mg Zn/kg from SAMZn was not different (P > 0.05) from chicks fed 15 mg Zn/kg from ZnSO4. Weight gain was not different (P > 0.05) when comparing the 2 sources of Zn hydroxychloride supplemented at 10 mg Zn/kg. Tibia ash Zn and total tibia Zn were increased (P < 0.05) by all Zn sources and responded linearly (P < 0.05) to Zn supplementation from ZnSO4 and SAMZn. Total tibia Zn concentration was not different (P > 0.05) for chicks fed 10 mg Zn/kg from either source of Zn hydroxychloride. Multiple linear regression of total tibia Zn on supplemental Zn intake (R2 = 0.95) resulted in a RBV of 115% for SAMZn compared with ZnSO4 (set at 100%). The RBV of SAMZn was higher (P < 0.05) than ZnSO4. In conclusion, relative bioavailability of Zn (based on tibia Zn) in Zn hydroxychloride from SAMZn was higher than feed grade ZnSO4 based on multiple regression slope-ratio analysis and was similar to that of IBZn Zn hydroxychloride based on tibia Zn responses to 10 mg/kg supplemental dietary Zn.

Molecular cytogenetic identification and nutritional composition evaluation of newly synthesized Triticum turgidum-Triticum boeoticum amphiploids (AABBAbAb).

Triticum boeoticum Boiss. (AbAb, 2n = 2x = 14) is a wheat-related species with the blue aleurone trait. In this study, 18 synthetic Triticum turgidum-Triticum boeoticum amphiploids were identified, which were derived from crosses between T. boeoticum and T. turgidum. Three probes (Oligo-pTa535, Oligo-pSc119.2, and Oligo-pTa713) for multicolor fluorescence in situ hybridization (mc-FISH) were combined with genomic in situ hybridization (GISH) to identify chromosomal composition. Seven nutritional indices (anthocyanins, protein, total essential amino acids TEAA, Fe, Zn, Mn and Cu) were measured, and the nutritional components of 18 synthetic amphiploids were comprehensively ranked by principal component analysis (PCA). The results showed that all three synthetic amphiploids used for cytological identification contained 42 chromosomes, including 14A, 14 B, and 14 Ab chromosomes. The average anthocyanin content was 82.830 μg/g to 207.606 μg/g in the whole meal of the 17 blue-grained lines (Syn-ABAb-1 to Syn-ABAb-17), which was obviously higher than that in the yellow-grained line Syn-ABAb-18 (6.346 μg/g). The crude protein content was between 154.406 and 180.517 g/kg, and the EAA content was 40.193-63.558 mg/g. The Fe, Zn, Mn and Cu levels in the 17 blue-grained lines were 60.55 to 97.41 mg/kg, 60.55-97.41 mg/kg, 35.11 to 65.20 mg/kg and 5.74 to 7.22 mg/kg, respectively, which were higher than those in the yellow-grained line. The contribution of the first three principal components reached 84%. The first principal component was mainly anthocyanins, Fe, Zn and Mn. The second principal component contained protein and amino acids, and the third component contained only Cu. The top 5 Triticum turgidum-Triticum boeoticum amphiploids were Syn-ABAb-11, Syn-ABAb-17, Syn-ABAb-5, Syn-ABAb-8 and Syn-ABAb-4. These amphidiploids exhibited the potential to serve as candidates for hybridization with common wheat, as indicated by comprehensive score rankings, toward enhancing the nutritional quality of wheat.

Desorption kinetic and sequential extraction of Pb and Zn in a contaminated soil amended with phosphate, lime, biochar, and biosolids.

The mining and metallurgical industry sector activities often release potential toxic elements (PTE) surrounding exploitation area. We evaluated the addition of phosphate and lime using the dosage of 0.5:1, 1:1, and 2:1 molar ratio of PO43- and CO32- to the sum of PTE, respectively, and also, biochar and biosolids using the dosage of 2.5, 5, and 10% (m:m) to immobilize PTE in contaminated forest soil (Pb (270mgkg-1) and Zn (858mgkg-1)) near an abandoned mine site in Brazil. The desorption by stirred flow kinetics revealed that 15% of the total Zn and 12% Pb contents are mobile before any amendment application. Phosphate amendment decreased Pb desorption but increased Zn desorption. Biochar and biosolids immobilize high amounts of Zn and Pb because of their high cation exchange capacities and alkaline properties; however, 20% biosolid dose increased Pb desorption. X-ray absorption spectroscopy suggested Zn-kerolite as the major species in the contaminated soil, likely from mine dust. The change in Zn speciation after soil amendment addition indicated that biochar and lime kept a high proportion of Zn-Al species, whereas phosphate and biosolids led to more Zn-Fe species. Our results pointed out that lime might reduce both Pb and Zn mobilities; however, field trials are crucial to confirm the immobilization efficiency of lime and other amendments over long term.

Sp-ICP-MS and HR–CS–GFAAS as useful available techniques for the size characterization and speciation of ionic and nanoparticular zinc in cosmetic and pharmaceutical samples

The use of zinc oxide nanoparticles (ZnO NPs) in cosmetic and pharmaceutical industry has been increased in recent years due to their good properties as solar radiation filters and antibacterial agent. According to the literature, the potential toxicity of these NPs could be size-dependent and the amount of solubilized metal. This work investigates new reliable and straightforward methodologies that enables the determination of ZnO NPs, discriminating them from ionic zinc in cosmetic samples. Two different techniques of analysis have been applied in this study: high-resolution continuum source graphite furnace atomic absorption spectrometry (HR–CS–GFAAS), and “single particle” inductively coupled plasma mass spectrometry (sp-ICP-MS). Triton X-100 has been used as a surfactant for the formation of homogeneous and stable slurries which allowed the determination of the concentration and sizes of ZnO NPs and Zn2+ in baby creams, eyeshadows, and lotions. A central composite design (CCD) was performed for the two techniques to optimize the concentration of Triton X-100 and sonication time. For validation purpose, the results of Zn2+ and ZnO NPs contents achieved by HR–CS–GFAAS were compared with the total Zn content obtained by acid digestion of the samples. A size comparison of the ZnO NPs was also carried out with the data obtained through the two methodologies and validated with transmission electron microscopy (TEM). In the case of TEM analysis, two different media were tried to study possible agglomerates and interactions between the particles and the matrix.

105 Awardee Talk: Timing of Dietary Zinc Supplementation During Gestation did not Affect Trace Element Concentrations in Sows and Their Piglets

Abstract Gestating sows (n = 267) were used to determine if timing of high dietary zinc supplementation in a commercial setting would reduce pre-weaning mortality of pigs and influence maternal and piglet copper (Cu), iron (Fe), and zinc (Zn) concentrations. Sows from three consecutive weekly farrowing groups were assigned randomly within parity to one of three dietary treatments consisting of: 1) Control: a corn-soybean meal diet containing 125 ppm supplemental Zn supplied by zinc hydroxychloride; 2) Breed-to-Farrow (B-to-F): as Control + 141 ppm supplemental Zn as ZnSO4 (266 ppm total supplemental Zn) fed from 5 days after breeding to farrowing; and 3) Day 110-to-Farrow (D110-to-F): as the Control diet fed from breeding to farrowing + 2,715 ppm supplemental Zn as ZnSO4 (2,840 ppm total supplemental Zn) starting on day 110 of gestation until farrowing. A subset of ten sows per treatment (n = 30; average parity = 3) were selected to assess Cu, Fe, and Zn concentrations of serum, colostrum, and milk. Sera were isolated from blood collections at allotment and the day before respective farrowing date of each sow. Colostrum was collected the day of farrowing and milk on day 2 of lactation. At farrowing, two average and two low birth weight pigs from each sow (n = 122) were selected for collections of serum and tail samples at days 1 and 2 of age, respectively. The statistical model included fixed effects of treatment, farrowing group, and the random effect of their interaction. The piglet model was similar but included the random term of pig nested within sow. There were no differences in concentrations of Cu, Fe, and Zn in sow serum, milk, or colostrum attributable to dietary treatment. Piglet serum concentrations of Cu, Fe, and Zn were unaffected by feeding gestating sows high levels of supplemental zinc at any time (Table). Low birth weight pigs born to sows fed the Control diet tended (P = 0.082) to have increased concentrations of Cu in tails compared with pigs born to sows fed high zinc. In conclusion, timing of dietary zinc supplementation to gestating sows had minimal influence on concentrations of important trace elements in sows and their offspring.

113 Effect of Birth Weight on Tissue Copper, Iron, and Zinc Concentrations in Piglets

Abstract Pigs (n = 3,990) were used in a previous study to determine if supplemental zinc fed to sows at various timepoints during gestation would reduce pre-weaning mortality. Additionally, data were analyzed to evaluate the effect of birth weight on tissue concentrations and distribution of copper (Cu), iron (Fe), and zinc (Zn) in piglets. Mixed parity sows were fed 1 of 3 diets: a control corn-soybean meal diet containing 125 ppm supplemental Zn supplied by zinc hydroxychloride, a diet consisting of the control + 141 ppm supplemental Zn as ZnSO4 (266 ppm total supplemental Zn) fed from 5 days after breeding to farrowing, or the control diet fed from breeding to farrowing + 2,715 ppm of supplemental Zn from ZnSO4 (2,840 ppm total supplemental Zn) starting on day 110 of gestation until farrowing. Two low and 2 average birth weight pigs (n = 122) were selected from 10 sows per treatment group to assess Cu, Fe, and Zn concentrations of serum and tails. Serum was collected from each pig at day 1 of age and tails were collected on day 2 of age. Liver tissue was collected from a subset of pigs (n = 65) that died naturally or were euthanized within 2 days of age. The statistical model included fixed effects of treatment and farrowing group, the random effect of their interaction, and the random effect of pig nested within sow. Serum concentrations of each trace element did not differ by birth weight (Table). Low birth weight piglets had greater concentrations of Fe (P = 0.018) and Cu (P = 0.031) in their tails than average birth weight pigs. No differences were observed in tail Zn concentration by birth weight. Notably, pigs that died naturally weighed less at birth than euthanized pigs (P &amp;lt; 0.001). Moreover, pigs that died naturally had greater hepatic Fe concentrations (P &amp;lt; 0.001) and tended to have greater liver Cu concentrations (P = 0.098) compared with euthanized pigs. The associations between tissue iron and copper concentrations and birth weight of piglets may have nutritional and pathophysiological implications and thus warrant further investigation.

Role of Temporal Zn Fertilization along with Zn Solubilizing Bacteria in Enhancing Zinc Content, Uptake, and Zinc Use Efficiency in Wheat Genotypes and Its Implications for Agronomic Biofortification

Wheat (Triticum aestivum L.) is a vital cereal crop for food security in Pakistan. In Zn-deficient soils, its productivity and quality suffer, affecting grain yield, Zn bioavailability, and nutrition, which can lead to malnutrition. Field experiments were conducted using factorial randomized block design at the Agricultural Research Institute (ARI) Tarnab, Peshawar, Pakistan to evaluate the impact of wheat genotypes (G1-TRB-72-311 synthetic hexaploid, G2-TRB-89-348 advanced line, and G3-Pirsabak-19-approved variety), Zn application methods (AM1: no Zn application, AM2: seed priming with 0.5% Zn, AM3: soil application of 10 kg ha−1 Zn, and AM4: foliar application of 0.5% Zn), and the experiment also explored the use of ZSB (BF1: with bacteria, BF0: without bacteria) to cope with Zn deficiency. The study revealed significant impacts on wheat’s Zn content, uptake, and nutrient efficiency, arising from genotypes variance, Zn application approaches, and ZSB. TRB-72-311 synthetic hexaploid genotype with 0.5% foliar Zn and ZSB excelled, enhancing grain (17.8%) and straw Zn (23.1%), increasing total Zn uptake (55.0%), reducing grain phytic acid (11.7%), and boosting Zn-related efficiencies in wheat. These results prompt further discussion regarding the potential implications for agricultural practices. In conclusion, utilizing the TRB-72-311 genotype with 0.5% foliar Zn application and ZSB enhances wheat’s Zn content, uptake, grain quality, and addresses malnutrition.

Determination of Serum Zinc and Phosphorus Levels in Patients with Hypothyroidism.

Various studies reported that serum zinc (Zn) and phosphorus (P) levels altered in patients with hypothyroidism and vice versa, but results were found inconsistent. It was aimed to find the association between serum Zn and P in patients with hypothyroidism. In this case-control study, a total of 100 subjects (50 newly diagnosed patients of hypothyroidism and 50 controls) were enrolled aged between 25 and 60years. Biochemical parameters such as thyroid profile, serum Zn, and P were estimated in each subject. A p < 0.05 was considered statistically significant. The mean level of body mass index (BMI), thyroid-stimulating hormone (TSH), and serum P was found significantly elevated in cases compared to controls (p < 0.001). However, the mean level of total triiodothyronine (T3), thyroxine (T4), and serum Zn was found significantly reduced in cases compared to controls (p < 0.001). The serum Zn has shown a significant negative correlation with T3 and BMI among cases (r = - 0.313 p < 0.05, r = - 0.338 p < 0.05, respectively). However, serum P has shown a significant positive correlation with TSH and BMI among cases (r = 0.310 p < 0.05, r = 0.449 p < 0.01, respectively). Regression analysis indicated that serum Zn significantly predicted hypothyroidism (p < 0.00). Similarly, serum P significantly predicted hypothyroidism (p < 0.007). Results showed that serum Zn levels were significantly reduced and serum P levels were significantly elevated in cases compared to controls. The serum Zn and serum P both significantly associated with hypothyroidism.

Soil Abandonment as a Trigger for Changes in Zn Fractionation in Afforested Former Vineyard Acidic Soils

Zinc is an essential element for plant nutrition, but it may cause toxicity depending on its bioavailability and potential transformation in soil. In vineyard soils, high concentrations of Zn are usually found, mainly due to agricultural practices. However, a great abandonment of vineyards has recently occurred, leading to changes in the total and bioavailable Zn concentrations, as well as Zn fractionation. We analyzed Zn concentrations (total, ZnT, and bioavailable, ZnED) and fractionation in the soil of three paired sites (PM, PT, and AR) up to depths of 50 cm in active and adjacent abandoned vineyards that were already transformed into forests. The ZnT averaged at 210 mg kg−1 among all studied vineyards. The results showed changes in the vertical pattern ZnT concentrations after vineyard abandonment at the PM and PT sites, while at the AR site, no great variation occurred. The ZnED (mean values = 7 mg kg−1) decreased after abandonment at PM and AR in the uppermost surface layers, while it increased in the top 10 cm at the PT site, reaching up to 60 mg kg−1. Regarding Zn fractionation in active vineyards, the residual fraction (ZnR) was the most abundant, followed by Zn bound to crystalline Fe and Al oxy-hydroxides (ZnC) and Zn bound to soil organic matter (ZnOM). After abandonment, the ZnR slightly increased and the ZnC slightly decreased at the PM and AR sites at all depths, while the ZnOM showed a noticeable variation in the uppermost 10 cm of the PT site. These results suggest that the soil organic matter that is provided during afforestation may play an important role in Zn fractionation and mobilization, depending on its humification degree and chemical stability. Zn mobilization could result in a positive nutrient supply for plants, but caution must be taken, since an excess of Zn could cause toxicity in long-term abandoned vineyards.

Impact Assessment of Zinc and Sulphur Application through Front Line Demonstrations in Paddy in Tribal Region of Central India

Front-line demonstrations were conducted at farmer’s fields of tribal villages of Jabalpur (7 No.) and Mandla (6 No.) districts during Kharif 2012 and 2013, respectively. Results revealed that the application of 5 kg Zinc +Recommended Dose of Fertilizer (Zn+ RDF ha-1) significantly increased the grain yield (4.53 and 4.70 t ha-1) zinc content in grain (13.18 and 12.97 mgkg-1) and total Zn uptake (190.31 and 184.79 g ha-1) and post-harvest available Zn (0.73 and 0.71 mg kg-1) over farmer’s practices or RDF during both the years. While, the S content in grain and straw of rice, their total S uptake and post- harvest available S increased significantly with the application of 40 kg S ha-1 +RDF and 5 kg Zn+40 kg S ha-1+RDF over farmers practice/ RDF/5 kg Zn ha-1+ RDF during both the years.&#x0D; With the application of 5 kg Zn +40 kg S +RDF ha-1, the extension gap was maximum (0.93 and 1.12 t ha-1) while, the least technology gap (0.47 and 0.30) and technology index (9.4 and 6.0%) were recorded. The performance of improved technology (5 kg Zn + RDF) emphasized the need to organize Kisan School in the deficient areas for the acceptance of improved technologies to bridge the wide extension gap.

Characterization of zinc uptake in seedlings of wheat cultivars differing in Zn-deficiency tolerance as affected by histidine

Knowledge of the characteristics of zinc (Zn) uptake by plant roots may help in understanding the reasons for variations in the Zn deficiency tolerance of plant cultivars. We investigated the apoplastic and symplastic Zn uptake and proton secretion by roots of three bread wheat genotypes (Triticum aestivum cvs. Rushan, Kavir, and Falat) and a durum wheat genotype (Triticum durum cv. Yavarus) under influence of histidine addition in a nutrient solution. Seedlings of wheat genotypes were planted in a nutrient solution containing 10 µM Zn with or without added 50 mM histidine (His). A control with no added Zn or histidine was also used. A significant variation was found among wheat genotypes in shoot Zn content and the characteristics of Zn uptake by roots. The addition of Zn enhanced shoot Zn content compared to the control while the effect of His was genotype-dependent. His addition in combination with Zn enhanced shoot Zn content in Rushan and Falat but not in Kavir and Yavarus compared with the only Zn supply treatment. For all wheat genotypes, the addition of Zn enhanced the total, apoplastic, and symplastic root Zn concentration compared to the control. The highest and lowest amounts of proton (H+) were secreted from the roots of Rushan and Yavarus genotypes, respectively. In all wheat genotypes except Falat, the combined addition of zinc and histidine enhanced root H+ secretion compared with the only supply of Zn. Higher plant Zn uptake was associated with a higher ability to secretion of H+ from roots and higher proportion of symplastic to apoplastic Zn.

Potential Impacts of Energy and Vehicle Transformation Through 2050 on Oxidative Stress-Inducing PM2.5 Metals Concentration in Japan.

The impacts of renewable energy shifting, passenger car electrification, and lightweighting through 2050 on the atmospheric concentrations of PM2.5 total mass and oxidative stress-inducing metals (PM2.5-Fe, Cu, and Zn) in Japan were evaluated using a regional meteorology-chemistry model. The surface concentrations of PM2.5 total mass, Fe, Cu, and Zn in the urban area decreased by 8%, 13%, 18%, and 5%, respectively. Battery electric vehicles (BEVs) have been considered to have no advantage in terms of non-exhaust PM emissions by previous studies. This is because the disadvantages (heavier weight increases tire wear, road wear, and resuspention) offset the advantages (regenerative braking system (RBS) reduces brake wear). However, the future lightweighting of drive battery and body frame were estimated to reduce all non-exhaust PM. Passenger car electrification only reduced PM2.5 concentration by 2%. However, Fe and Cu concentrations were more reduced (-8% and -13%, respectively) because they have high brake wear-derived and significantly reflects the benefits of BEV's RBS. The water-soluble fraction concentration of metals (induces oxidative stress in the body) was estimated based on aerosol acidity. The reduction of SOx, NOx, and NH3 emissions from on-road and thermal power plants slightly changed the aerosol acidity (pH±0.2). However, it had a negligible effect on water-soluble metal concentrations (maximum +2% for Fe and +0.5% for Cu and Zn). Therefore, the metal emissions reduction was more important than gaseous pollutants in decreasing the water-soluble metals that induces respiratory oxidative stress and passenger car electrification and lightweighting were effective means of achieving this.

Faucet-mounted point-of-use drinking water filters to improve water quality in households served by private wells

Approximately 13 % of Americans rely on private wells for household potable water. As private wells are not regulated beyond initial construction and often employ limited or no treatment, source water from wells can be vulnerable to contamination. While several studies have assessed applications of point-of-use (POU) filters in improving municipal tap water quality, few have investigated their use with private well water. This effort aims to build on previous examinations of POU treatment as a strategy to reduce adverse household drinking water exposures by: 1) assessing the effectiveness of commercially available faucet-mounted POU filters for improving microbial and chemical water quality in homes with private wells; and 2) documenting household ease of use and satisfaction with the filters. Faucet-mounted POU filters were distributed to 21 homes reliant on private wells in southern West Virginia and southwestern Virginia. Study participants were asked to collect water samples from two taps in their homes pre-filter installation, and again two-weeks and four-weeks post-installation. Participants filled out surveys about perceptions of their drinking water and the filter. Concentrations of Total Coliform, Ba, Cd, Cr, U, Cu, Pb, Al, Fe, Mn, Zn, and Sr were significantly lower (p < 0.05, Wilcoxon Rank Sum) in filtered water samples compared to paired unfiltered samples (n = 42) for the study period. However, concentrations of certain contaminants in filtered samples from homes with high levels of source water contamination still exceeded drinking water standards. Less than half of study participants reported that they intended to keep using the filters, citing issues of flowrate. Our findings suggest that faucet-mounted POU filters, while effective in reducing contaminants, might not be an appropriate intervention to improve water quality for all homes on private well water. Future investigation is required to improve filter user satisfaction and better assess appropriate source water chemistries for implementation.

Long-term bioorganic and organic fertilization improved soil quality and multifunctionality under continuous cropping in watermelon

Continuous cropping has can majorly damage the soil ecosystem, leading to an increased prevalence of pathogenic microorganisms and severe yield losses for watermelons. Multiple prevention strategies have been adopted to overcome this obstacle, among which the application of bioorganic fertilizer can improve microbiome deterioration. However, the response of soil ecosystem multifunctionality and soil quality to fertilizer regimes under continuous cropping remains poorly understood. In this study, based on an 8-year field experiment, we evaluated soil health and ecosystem multifunctionality under different fertilization treatments. Long-term bio-organic fertilization preserved soil electrical conductivity and increased total Cu, Zn, Fe, Mn, Ca, and Mg, total and available nutrients, and enzyme activities compared with those in unfertilized control (CK) and chemical fertilizer treatments. Enzyme activities and yield rapidly changed, indicating their sensitivity to these management practices. Conversely, soil pH, biodiversity, medium/trace elements, and total NPK content were more resistant to change than enzyme activities, suggesting higher stability over time. The area of soil quality index under bio-organic fertilization was 1.2–2.9 times larger than that under CK treatment. Applying biological organic fertilizer and a mixture of chemical and organic fertilizers improved the multifunctionality decline caused by continuous cropping by 1.1–1.4 times, whereas the effect of the chemical fertilizer was weak. Soil health was positively correlated with ecosystem multifunctionality. These findings suggest that long-term bioorganic and organic fertilization is an effective strategy for improving soil quality and multifunctionality in continuous watermelon crops while also contributing toward a more sustainable agricultural system.

Soil and foliar application of Zn enhances its biofortification, bioavailability and productivity in both biofortified and non-biofortified wheat varieties

In a two-year field study, the agronomic approaches to enhance zinc content and bioavailability in grains of both biofortified and non-biofortified wheat varieties were investigated. During both years of the study, the biofortified variety PBW 1 Zn demonstrated significantly higher grain yield (5.8 and 5.7 t ha–1), which were statistically comparable to the non-biofortified variety HD 2967 (5.7 and 5.5 t ha–1). Similarly, upon Zn fertilization, PBW 1 Zn exhibited a 25% higher Zn concentrations in grains (50 mg kg–1), along with a greater total Zn accumulation (504 g ha–1) and higher Zn mobilization efficiency index (ZnMEI) of 2.0. Additionally, the PBW 1 Zn demonstrated elevated grain nitrogen content (2.2%) and total nitrogen accumulation (189 kg ha–1). Conversely, it displayed a reduced phosphorus content (0.30%), phytic acid content (9 mg g–1), and PA/Zn molar ratio (18) in its grains. Among the Zn fertilization strategies, soil + foliar Zn resulted in higher grain and straw yields by 14% and 7%, respectively, followed by foliar application, and soil application. Further, soil + foliar application of Zn increased the Zn concentration in grain and straw by 47% and 37%, respectively, and grain N content by 19%. Simultaneously, this method decreased the phytic acid content and PA/Zn molar ratio by 20%, and 47%, respectively. Conclusively, the soil + foliar Zn application augmented the qualities of the genetically biofortified variety PBW 1 Zn, leading to higher yields, nutritional attributes, and bioavailability of Zn.

Drivers and mechanisms of spontaneous plant community succession in abandoned Pb[sbnd]Zn mining areas in Yunnan, China

The drivers and mechanisms underlying succession and the spontaneous formation of plant communities in mining wasteland remain largely unknown. This study investigated the use of nature-based restoration to facilitate the recovery of viable plant communities in mining wasteland. It was found that scientific analyses of spontaneously formed plant communities in abandoned mining areas can provide insights for nature-based restoration. A chronosequence (“space for time”) approach was used to establish sites representing three successional periods with six successional stages, and 90 quadrats were constructed to investigate changes in plant species and functional diversity during succession in abandoned PbZn mining areas. A total of 140 soil samples were collected to identify changes in soil properties, including plant nutrient and heavy metal concentrations. Then, this paper used structural equation models to analyze the mechanisms that drive succession. It was found that the functional diversity of plant communities fluctuated substantially during succession. Species had similar functional traits in early and mid-succession, but traits tended to diverge during late succession. Soil bulk density and soil organic matter gradually increased during succession. Total nitrogen (N), pH, and soil Zn concentrations first increased and then decreased during succession. Concentrations of Mn and Cd gradually decreased during succession. During early succession, soil organic matter was the key factor driving plant colonization and succession. During mid-succession, soil Zn functioned as an environmental filter factor limiting the rates of succession in mining wasteland communities. During late succession, soil bulk density and competition for nutrient resources contributed to more balanced differentiation among plant species. This thesis proposed that a nature-based strategy for the stabilization of abandoned mining lands could facilitate effective plant community restoration that promotes ecosystem services and functioning.

Characterization of elements and carbon and nitrogen stable isotopes in American ginseng (Panax quinquefolius L): Determining the geographical origin combining with chemometrics

American ginseng is a valued medicinal and food homologous herbal, which geographical source governs its medicinal and economical values. This work aimed to identify the American ginseng from four regions (including Northeast provinces and Shandong province in China, America, and Canada) using ICP-MS and EA-IRMS. American ginseng harvested in China had significantly higher levels of the essential elements of K (18.7 g/kg), Ca (2.3 g/kg), Na (2.0 g/kg), Mg (1.9 g/kg), P (2.2 g/kg), Mn (59.6 mg/kg), and Cu (12.0 mg/kg), and lower levels of Fe (40.2 mg/kg), total Zn (18.1 mg/kg), B (16.5 mg/kg), and Mo (182.6 μg/kg) than those in America. Similarly, American ginseng harvested in Canada had significantly lower levels of the essential elements of Ca (1.2 g/kg), Fe (7.8 mg/kg), and B (16.5 mg/kg) than those in America. American ginseng from four regions had the significant difference in δ15N value. The highest and lowest δ15N in American ginseng were found in Shandong (3.5‰) and the Canada (-4.4‰), respectively. Multi-elements and δ15N combined with SVM, LDA, RF, and FNN models gave the good classification for American ginseng from four regions. The best FNN model obtained the 100% accuracy. The results showed that elements and δ15N are the useful indictors to identify the geographical origin of American ginseng.

Metal speciation in sediments and bioaccumulation in edible bivalves to assess metal toxicity in a sand mining impacted tropical (Aghanashini) estuary, southern India

The study aims to understand the metal toxicity through the relationship between bioavailability in sediments and bioaccumulation in edible bivalves in an estuary subjected to extensive sand mining. The higher deposition of total Fe, Mn, Ni and Zn in the middle region (core M) was ascribed to estuarine processes and proximity to anthropogenic sources. EF revealed moderate to severe enrichment of Ni and Cu in sediments. Igeo showed moderate degree of pollution from Co, moderate to strong pollution from Ni and strong to extreme level of pollution from Cu. In core N, the average bioavailable concentration of Fe, Mn, Zn, Cu, Co and Ni was 1.76 %, 43.18 %, 59.14 %, 62.11 %, 60.42 % and 27.33 % respectively. The average bioavailable concentration of Fe (61.23 %), Mn (56.87 %), Cu (67.98 %), Co (69.77 %) and Ni (40.99 %) was higher in the core M as compared to core N except for Zn (56.98 %). The significant (>25.00 %) proportion of metals in bioavailable fractions in cores N and M construed their non-natural sources. Metal speciation study indicated bioavailability to fauna that likely to enhance by extensive sand mining. The level of Fe, Mn, Zn, Cu and Ni in Saccostrea cucullate, Meretrix casta and Villorita cyprinoides revealed toxicity to bivalves and probably to humans.

Study on the treatment of cyanide gold extraction wastewater by persulfate-electrochemical oxidation

The cyanide gold extraction wastewater from a gold smelter was treated using a persulfate-electrochemical oxidation (PS-EO) coupling process. The optimal process conditions and significance level of each factor were determined using orthogonal experiments, and the precipitates and cathodic precipitates in the system were analyzed and characterized using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscope-energy dispersive spectroscopy (SEM-EDS), and the oxidation removal reaction mechanism of cyanide was further explored. The results showed that voltage, time and PS concentration were the main influencing factors of the cyanide removal extent. When the voltage was 5 V, PS concentration 0.5 g L–1, pH 7, plate spacing 2.5 cm and reaction time 240 min, the removal extents of total cyanide (CNT), free cyanide (CN–), Cu and Zn ions in wastewater reached 98.33 %, 100 %, 99.53 % and 98.86 %, respectively. The removal of cyanide was mainly attributed to the indirect oxidation by SO4•–, •OH and O2•– active radicals produced by activated PS and the direct oxidation of S2O82–. The contribution rate of S2O82– direct oxidation was 42.38 %. The oxidation contribution rates of SO4•–, •OH and O2•– active free radicals were 15.75 %, 29.33 % and 12.54 %, respectively. Compared with simple PS and EO treatment processes, the PS-EO combined process reduced the amount of oxidants and helped to improve the current density of the system, as well as the generation of active free radicals such as SO4•–, •OH and O2•–. Additionally, after PS-EO treatment, there were almost no precipitates such as Zn(CN)2, CuCN, Zn(OH)2 and Cu(OH)2 produced in the wastewater. The cyanide ions in complex ions such as Cu(CN)32– and Zn(CN)42– were completely oxidized to N2 and CO2, and then under the influence of an electric field, the released Cu2+ and Zn2+ ions were directed to migrate to the cathode and precipitate.Finally, the treated wastewater could be directly returned to the grinding or leaching the ore process, thus achieving the goals of being harmless and utilizing cyanide wastewater resources.

Quantitative Distribution and Contamination Risk Assessment of Cu and Zn in Municipal Sewage Sludge

One of the methods of managing sewage sludge (SS) is its soil application. This possibility is promoted by the chemical composition rich in organic matter and nutrients. However, heavy metal contents in SS must meet respective permissible limits. Among the heavy metals in SS, Cu and Zn are found in the largest amount; thus, this study focuses on these elements. The main aim of the study is to investigate the quantitative distribution of metals in sequentially separated fractions of sewage sludge. Additionally, the potential risk of environmental contamination with heavy metals was assessed in the case of SS application for agricultural purposes. The relevant analyses were conducted on four different examples of municipal SS. Based on the total amounts as well as those determined in the SS fractions, the following indices were calculated: Igeo (geoaccumulation index), ICF, (individual contamination factor), and RAC (risk assessment code). The use of data from the sequential analysis as well as the calculated indices made it possible to assess the usefulness of SS in practice in terms of potential introduction of Cu and Zn into the environment with the sludge dose. It was found that total Cu (Cutot) and Zn (Zntot) did not exceed the permissible limits binding within respective Polish and international regulations. Regardless of the years of study and the analyzed SS, Cutot ranged from 260.9 to 393.5 mg·kg−1, and Zntot from 475.5 to 1153.1 mg·kg−1. The amounts of Cu and Zn were predominantly reducible (bound to iron and manganese hydroxides, Fr. II) and oxidizable complexes (bound to organic matter and sulfides, Fr. III). The average amounts of Cu in Fr. II ranged from 149.4 to 172.4 mg·kg−1, while those of Zn in Fr. II ranged from 370.9 to 754.6 mg·kg−1. Cu amounts in Fr. III were from 160.9 to 183 mg·kg−1 and Zn amounts in Fr. III were from 104.9 to 171.9 mg·kg−1. Total content of metals as well as TOC values strongly determined the quantitative level of both elements in the SS fractions. Generally, with the increase in the total amount of metals, their levels in the sludge fractions increased. In turn, the increase in TOC resulted in a decrease in the amounts of Cu and Zn in the sludge fractions. Calculated Igeo and ICF ratios showed high and very high SS contamination with Cu and Zn. Igeo values for Cu, regardless of the year of study and sludge sample, that ranged from 4.62 to 5.43 and for Zn from 3.41 to 4.86. At the same time, the ICF values for Cu ranged from 8.59–23.04, and for Zn 15.42–44.47. The RAC values indicated a low (Cu) and medium (Zn) risk of using SS in terms of the potential metal availability in the environment. The RAC values ranged from 1.46 to 4.40% for Cu and from 9.63 to 23.13% for Zn.