Source Of Manganese Research Articles

To move or not to move? Manganese oxide procurement during the Archaic period in the Atacama Desert

This paper investigates the possible sources of manganese (Mn) acquisition for the Chinchorro population of Arica, in northern Chile. To accomplish this, we analyse Mn distribution using digital geological map data and SEM/EDX and XRD analysis to chemically characterize twenty-five samples. Of these, eighteen were taken from geological sediments and seven from black pigments related to the Chinchorro mummification tradition (ca. 6950–2950 BP) from the archaeological sites of Maestranza 1, Morro 1, and Playa Miller 8. In contrast with previous highland Mn acquisition hypotheses, our results show that the lowland and coastal geological sediments near the Lluta river mouth have high Mn concentration, with a granular form that was easy to mine and process. The archaeological samples show that the Chinchorro used a high-grade Mn, without the need to use large mining tools (e.g. hafted hammers). This supports the proposition that there was a local (lowland and coastal) acquisition of good quality Mn, minimizing long-distance travel to the highlands for Mn procurement. The abundance of local finely-ground Mn sources can explain the cultural centrality of this pigment for several millennia during the Archaic period.

Manganese sources and rates impact plant Mn concentrations and soil Mn fractions

AbstractManganese (Mn) is an essential micronutrient for all organisms. In plants, Mn plays a critical role in photosynthesis and as a structural component of enzymes. In soils, Mn exists as different fractions of varying availability to plants. Mn fertilizers can be used to increase Mn availability to plants but are easily converted from a plant‐available fraction (exchangeable Mn) to an unavailable fraction (Mn‐oxides). Little research has been done in agricultural settings on soil Mn fractions; thus, the objective of this experiment was to study the effect of Mn additions on soil Mn fractions and plant Mn concentration. A greenhouse experiment was conducted by growing soybean (Glycine max) treated with three Mn application rates (recommended or 1×, 10×, and 50×) of two sources (MnSO4 and Mn ethylenediamine tetraacetic acid [MnEDTA]). Soil Mn fractions (Mehlich‐1 extractable, exchangeable, organic‐bound, Mn‐oxide, residual) were quantified via sequential Mn extraction procedures. Bioavailability was evaluated by measuring soybean leaf Mn concentrations. Both fertilizer types increased available soil Mn fractions. Leaf Mn concentration increased with MnSO4 50× application at the V3 stage and decreased with MnEDTA addition at the V3 and R2 stages. Mn additions likely resulted in the conversion of Mn into unavailable fractions. This was amplified by higher application rates, where total Mn increased by 18.5%, but available Mn decreased by 4.3% relative to initial soil values. Thus, our study showed that adding Mn to soils does not necessarily increase plant‐available Mn.

Voltammetric determination of inorganic arsenic in mildly acidified (pH 4.7) groundwaters from Mexico and India

Routine monitoring of inorganic arsenic in groundwater using sensitive, reliable, easy-to-use and affordable analytical methods is integral to identifying sources, and delivering appropriate remediation solutions, to the widespread global issue of arsenic pollution. Voltammetry has many advantages over other analytical techniques, but the low electroactivity of arsenic(V) requires the use of either reducing agents or relatively strong acidic conditions, which both complicate the analytical procedures, and require more complex material handling by skilled operators. Here, we present the voltammetric determination of total inorganic arsenic in conditions of near-neutral pH using a new commercially available 25 μm diameter gold microwire (called the Gold Wirebond), which is described here for the first time. The method is based on the addition of low concentrations of permanganate (10 μM MnO4−) which fulfils two roles: (1) to ensure that all inorganic arsenic is present as arsenate by chemically oxidising arsenite to arsenate and, (2) to provide a source of manganese allowing the sensitive detection of arsenate by anodic stripping voltammetry at a gold electrode. Tests were carried out in synthetic solutions of various pH (ranging from 4.7 to 9) in presence/absence of chloride. The best response was obtained in 0.25 M chloride-containing acetate buffer resulting in analytical parameters (limit of detection of 0.28 μg L−1 for 10 s deposition time, linear range up to 20 μg L−1 and a sensitivity of 63.5 nA ppb−1. s−1) better than those obtained in acidic conditions. We used this new method to measure arsenic concentrations in contrasting groundwaters: the reducing, arsenite-rich groundwaters of India (West Bengal and Bihar regions) and the oxidising, arsenate-rich groundwaters of Mexico (Guanajuato region). Very good agreement was obtained in all groundwaters with arsenic concentrations measured by inductively coupled plasma-mass spectrometry (slope = +1.029, R2 = 0.99). The voltammetric method is sensitive, faster than other voltammetric techniques for detection of arsenic (typically 10 min per sample including triplicate measurements and 2 standard additions), easier to implement than previous methods (no acidic conditions, no chemical reduction required, reproducible sensor, can be used by non-voltammetric experts) and could enable cheaper groundwater surveying campaigns with in-the-field analysis for quick data reporting, even in remote communities.

Occurrence, Source, and Mobilization of Iron, Manganese, and Arsenic Pollution in Shallow Aquifer

This investigation is aimed at exploring the mobilization and sources of Fe, Mn, and As in aquifers through geochemical characterization, spatial analysis, and statistical approaches. Analytical results showed that the average concentrations of Fe (10.17 mg/L) and Mn (3.6 mg/L) crossed the guideline value but not As in all samples. In this study, the elevated levels of dissolved organic carbon, salinity, total hardness, and log10 pCO2; the lower value of dissolved oxygen; and some oxidizing groups of samples influence the reductive environment of Fe and Mn weathering. The investigation illustrated that the source of both metals on the upper platform is consolidated silty soil and aquifer sediment, whereas, in the river valley, they originate from Fe and Mn-bearing nodules in the rich clay layer and tidal mud. In addition, the frequent fluctuation of river flow, excess water mining, and an unbalanced recharge/discharge ratio are the causes of higher concentrations of both metals. The correlation matrix and factor analysis of Fe and Mn with redox-sensitive water variables confirmed that a favourable reductive situation fosters the Fe and Mn release process. Studies have also shown the significant possibility of forming a metal complex with organic and inorganic substances. The higher dissolution of Fe and Mn minerals causes As to be adsorbed on them, leading to less release of As into groundwater. This investigation provides a basis for the rational use of groundwater and the defense of public health in zones with high Fe and Mn contents.

Distribution Characteristics and Genesis of Iron and Manganese Ions in Groundwater of Eastern Sanjiang Plain, China

Groundwater resources are an essential component of global water resources. Long-term consumption of groundwater exceeding the standard levels for iron and manganese can lead to chronic diseases, posing a threat to human health. The Sanjiang Plain is the largest swamp wetland area in China and has high levels of iron and manganese in the groundwater, but the cause still needs to be clarified. Based on the results of water quality tests of 41 groundwater samples in the Eastern Sanjiang Plain, this paper analyzes the distribution characteristics and causes of iron and manganese from the perspectives of the original strata environment, redox conditions, pH conditions, and hydrochemical indicator factors in the research area, using statistical methods and GIS technology. The results show that high iron and manganese content in groundwater is prevalent in the Eastern Sanjiang Plain, and the exceedance rate of manganese is higher than that of iron (87.80% and 82.90%, respectively). The primary sources of iron and manganese in groundwater are iron and manganese minerals in the original strata environment. Influenced by factors such as acidic conditions, reducing environment, and rich organic matter, insoluble high-valent iron and manganese oxides are reduced to low-valent and soluble divalent iron and manganese. At the same time, groundwater’s high mineralization and evaporation concentration are conducive to increased iron and manganese content, while the influence of human activities is small.

Comparative Study of the Nutritional and Chemical Composition of New Oil Rape, Safflower and Mustard Seed Varieties Developed and Grown in Serbia.

Oilseed crops are widely cultivated and are related to nutrition and human health as valuable nutraceutical sources with valuable biological properties. The growing demand for oil plants used in human and animal nutrition or for the processing industry has contributed to the diversification and development of a new variety of oil crops. Increased oil crop diversity, besides ensuring reduced sensitivity to pests and climate conditions, has also led to improved nutritional values. In order to enable oil crop cultivation to become commercially sustainable, a comprehensive characterization of newly created varieties of oilseeds, including their nutritional and chemical composition, is required. In this study, two varieties of safflower and white and black mustard were investigated as alternative oil species for nutritional parameters, mainly protein, fat, carbohydrate, moisture, ash, polyphenols, flavonoids, chlorophylls contents, acids and mineral composition, and compared with those of two different genotypes of rapeseeds as a traditional oil crop plant. The proximate analysis found that the highest oil content was found in the oil rape NS Svetlana genotype (33.23%), while the lowest was in black mustard (25.37%). The protein content varies from around 26% in safflower samples to 34.63%, determined in white mustard. High content of unsaturated fatty acids and low content of saturated fatty acid was observed in the analyzed samples. In mineral analysis, the dominant elements were phosphorus, potassium, calcium and magnesium, in descending order. The observed oil crops are also good sources of microelements, including iron, copper, manganese and zinc, accompanied by high antioxidant activity due to the presence of significant amounts of polyphenolic and flavonoid compounds.

Mn3O4 nanoparticles decorated porous reduced graphene oxide with excellent oxidase-like activity for fast colorimetric detection of ascorbic acid.

Mn3O4 nanoparticles composed of porous reduced graphene oxide nanosheets (Mn3O4@p-rGO) with enhanced oxidase-like activity were successfully fabricated through an in-situ approach for fast colorimetric detection of ascorbic acid (AA). The residual Mn2+ in the GO suspension of Hummers method was directly reused as the manganese source, improving the atom utilization efficiency. Benefiting from the uniform distribution of Mn3O4 nanoparticles on the surface of p-rGO nanosheets, the nanocomposite exhibited larger surface area, more active sites, and accelerated electron transfer efficiency, which enhanced the oxidase-like activity. Mn3O4@p-rGO nanocomposite efficiently activate dissolved O2 to generate singlet oxygen (1O2), leading to high oxidation capacity toward the substrate 3,3',5,5'-tetramethylbenzidine (TMB) without the extra addition of H2O2. Furthermore, the prominent absorption peak of the blue ox-TMB at 652nm gradually decreased in the presence of AA, and a facile and fast colorimetric sensor was constructed with agood linear relationship (0.5-80μM) and low LOD (0.278μM) toward AA. Owing to the simplicity and excellent stability of the sensing platform, its practical application for AA detection in juices has shown good feasibility and reliability compared with HPLC and the 2, 4-dinitrophenylhydrazine colorimetric method. The oxidase-like Mn3O4@p-rGO provides a versatile platform for applications in food testing and disease diagnosis.

Ultrasonic-assisted, rapid preparation of mesoporous MnCO3 for electrochemical supercapacitor applications: A novel approach

Accounting for the methods opted in the preparation of nanoscale materials with high surface rea, average pore size and volume needs high energy and time-consuming processes. This work discloses a quick, scalable, and simple co-precipitation method for synthesizing MnCO3 for use in supercapacitors as a working electrode using MnSO4 and (NH4)HCO3 as the manganese and carbonate sources, respectively. As-synthesized sample is subjected to sonication at different periods for evaluating the effect of capacitance and the size of MnCO3 particles. Investigations using X-ray diffraction and X-ray photoelectron spectroscopy proves that MnCO3 can form the rhodochrosite phase and microscopical analyses reveals that nanograins smaller than 10 nm aggregated into spherical particles that were submicron in size. N2 adsorption–desorption isotherm isotherms validates the mesoporosity of MnCO3. The Galvanostatic charge–discharge cycling and cyclic voltammetry techniques examine the capacitance characteristics of mesoporous MnCO3 in both 0.1 Mg(ClO4)2 and Na2SO4 aqueous solutions. Mesoporous MnCO3 delivers a specific capacitance of 188F g−1 and 124F g−1 at a specific current of 0.33 A g−1 in both Mg(ClO4)2 and Na2SO4 aqueous solutions with a loading level of 1.5 mg cm−2. Additionally, mesoporous MnCO3 shows strong rate capability and stable cycle-life over 10,000 cycles. These demonstrates the mesoporous nanomaterials with high surface area and volume can enhance the energy storage capacitance of a supercapacitor.

Effects of different manganese sources on nutrient digestibility, fecal bacterial community, and mineral excretion of weaning dairy calves.

Mn, which is an essential trace mineral for all animals, has functions in skeletal system development, carbohydrate and lipid metabolism. The aim of this study was to clarify the effects of different manganese (Mn) sources in basal diets on nutrient apparent digestibility, fecal microbes, and mineral elements excretion before and after weaning. A total of 15 Holstein heifer calves (6-week-old, 82.71 ± 1.35, mean ± standard error) were randomly designed into three groups (five each): no extra Mn supplemented (CON), 20 mg Mn/kg (dry matter basis) in the form of chelates of lysine and glutamic acid in a mixture of 1:1 (LGM), and 20 mg Mn/kg (dry matter basis) in the form of MnSO4. All calves were weaned at 8 weeks of age. The experiment lasted for 28 days (14 days before weaning and 14 days after weaning). Dry matter intake (DMI) was recorded daily. The animals were weighed by electronic walk-over, and body size indices were collected using tape on days -14, -1, and 14 of weaning. The feces of calves was collected to measure the apparent digestibility of nutrients (acid insoluble ash was an internal marker) and bacterial community on days -1, 1, 3, 7, and 14 of weaning. Fecal mineral concentration was determined by inductively coupled plasma emission spectroscopy on days -1, 1, 7, and 14 of weaning. The results showed that, compared with the CON group, adding LGM to diets containing 158.82 mg/kg Mn increased the apparent digestibility (P < 0.05). The Chao 1 and Shannon index of fecal bacteria decreased at day 1 in the LGM and MnSO4 groups and increased after weaning. The PCoA results indicated that the LGM group was distinctly separate from the CON and MnSO4 groups during the whole experimental period. Significant differences (P < 0.05) were observed in the relative abundance of two phyla (Proteobacteria and Spirochaetota) and eight genera (Alloprevotella, Prevotellaceae_UCG-001, Clostridia UCG 014, RF39, UCG-010, Pseudomonas, Ralstonia, and Treponema) in three groups. Moreover, the LGM group showed less excretion of Fe, P, and Mn than the MnSO4 group. In summary, 20 mg Mn/kg diet supplementation improved nutrient digestibility, changed the fecal microbial community, and reduced mineral excretion. Organic Mn supplementation in the diet had more advantages over the sulfate forms in weaning calves.

Characterization of pristine bismuth manganite thin films deposited on glass substrates by spray pyrolysis technique

The multiferroic Bismuth Manganite (BiMnO3) material which has wide application in memory device. The effect of solute and annealing temperature on spray pyrolyzed pure phase BiMnO3 was studied in detail. The deposited thin films showed the polycrystalline nature with bismuth oxide and manganese oxide impurity phases. The salt considered for the manganese source has effect on obtaining bismuth manganite phase and the annealing temperature has effect on the crystalline nature of the film. The needle like surface morphology was noticed from the deposits. The variation of energy band gap noticed with used solutes and annealing temperature due to change in chemical reaction during deposition and crystallinity respectively. The least energy band gap of 1.81 eV was observed by optimizing the deposition parameters. The blue emission and different defect related peaks are observed in photoluminescence. This work helps in developing prominent material for optoelectronic application.

Physical and Chemical Characterization and Bioavailability Evaluation In Vivo of Amaranth Protein Concentrate.

Special attention is being paid to the study of amaranth proteins. They are characterized by a high biological value that significantly exceeds those of grain crops. The production of protein concentrate from amaranth flour includes preliminary enzymatic hydrolysis, extraction of the resulting mixture, protein precipitation, microfiltration, and freeze-drying. In our study, the obtained amaranth protein concentrate was limited by valine, with an amino acid score of 74%. The true digestibility of the amaranth protein concentrate determined in vivo was 97.6 ± 0.3%, which was significantly lower than that of casein (99.3 ± 0.2%). The protein digestibility-corrected amino acid score value of the concentrate was 72.2%. The obtained concentrate was a rich source of selenium, copper, magnesium, manganese, and iron. Ferulic acid was the only polyphenolic compound found in the amaranth protein concentrate, but its content was significantly greater compared to the original flour. Saponins were not removed completely during the process of obtaining the amaranth protein concentrate. We identified 15 saponins in the concentrate, mainly of the bidesmoside type, the sapogenins of which are related derivatives of oleanolic acid. Thus, the developed amaranth protein concentrate can be used as an ingredient in functional food products, with a high biological value.

Ruminal Solubility and Bioavailability of Inorganic Trace Mineral Sources and Effects on Fermentation Activity Measured in Vitro

The aim of this study was to assess the effects of supplementation with inorganic sources of manganese (MnO, MnSO4), zinc (ZnO, ZnSO4) and copper (CuSO4) at different levels (0.06%DM for Mn, 0.05%DM for Zn; 0.01 and 0.05%DM for Cu) on in vitro rumen fermentation, solubility and bioavailability. Fermentation activity was measured by total gas production (TGP) and dry matter degradability after 70 h of fermentation (dDM%). Trace mineral (TM) solubility was estimated via the TM concentration in the supernatant of the final fermentation medium (SOL) and TM bioavailability from the TM concentration in a bacterial-enriched fraction (BACT). Mn (regardless of source) and ZnO tended (p &lt; 0.10) to decrease, while Cu showed no significant effect on TGP. The addition of inorganic Mn and of ZnO tended (p &lt; 0.10) to decrease, ZnSO4 tended to increase (p &lt; 0.10), whilst Cu showed no effect on dDM%. Concerning solubility, Mn (MnO and MnSO4), ZnSO4 and CuSO4 significantly (p &lt; 0.05, p &lt; 0.001 and p &lt; 0.01) increased, while ZnO did not affect TM content in the SOL. These results indicate that MnSO4, ZnSO4 and CuSO4 are highly soluble, MnO is quite soluble, while ZnO has a low solubility in the rumen. Based on the TM content in BACT, MnO, MnS4 and CuSO4 have high bioavailability, while ZnO is poorly assimilated by rumen bacteria. However, the lack of clear inhibition or improvement in fermentations suggests that the rumen microbiota have a low requirement for TM supplementation.

Construction of surface oxygen vacancy active sites upon MnOx/AC composite catalysts for efficient coupling adsorption and oxidation of toluene

Activated carbon (AC) has been widely used as adsorbent and support of noble metal catalysts for the elimination of VOCs, owing to its high specific surface area and effective regulation of interfacial properties of catalysts via metal-support interaction. Herein, a series of MnOx/AC composite catalysts are prepared by in-situ redox precipitation method using KMnO4 as manganese source, ethylene glycol (EG) as reducing agent and coconut shell-based AC as active carrier. The obtained MnOx/AC catalysts have been fully characterized by XRD, SEM, TEM, N2 adsorption-desorption, FT-IR, XPS, EPR, H2-TPR, TPD-MS and toluene-TPSR-Ms (with and without O2) and their catalytic properties are evaluated for low temperature oxidation of toluene. It is found that the introduction of AC support significantly enhanced the adsorption capacity of toluene upon the MnOx/AC composite catalysts. Amongst, the MnOx/AC-0.3 shows excellent low-temperature catalytic activity (T90 = 193 °C), which can be related to highly efficient synergy of AC and MnOx species in toluene combustion. Especially, the construction of efficient MnOx/AC interfaces with more oxygen vacancy active sites, better lattice oxygen mobility, and stronger molecular oxygen activation ability, makes MnOx/AC-0.3 composite catalyst possess the best coupling adsorption oxidation capacity of toluene, and thus resulting in significant improvement in catalytic performance. Additionally, the obtained MnOx/AC-0.3 catalyst has also exhibited good catalytic stability and water resistance (5 vol%). This work deepens the understanding of the metal-support interaction in MnOx/AC composite catalysts and provides new ideas for the design of environmentally friendly catalysts.

A GIS-based analysis of groundwater manganese and nitrate concentration for sustainable water supply

Groundwater is the main source of water supply in Sleman Regency. Although the water quantity is not an issue, the quality of groundwater should be understood to ensure the sustainability of the water supply. A previous study shows an increase in manganese (Mn) and nitrate (NO3) concentration in groundwater, yet the concentration distribution is unknown. Therefore, this study aims to develop a map of the spatial distribution pattern and to analyze the potential source of manganese and nitrate in groundwater in Sleman Regency in Yogyakarta Province. The method used is mapping groundwater quality using the ArcGIS application, analyzing groundwater pollution with water quality standards in the Indonesian Ministry of Health regulation number 492/Menkes/per/IV/2010 regarding drinking water quality requirements, and identifying the potential source of high pollution. Data processing uses the ArcGIS 10.8 application by performing the IDW (Inverse Distance Weighting) Interpolation technique. The result of this study has obtained a map of the distribution of groundwater quality for manganese and nitrate from 2017-2019. Manganese contamination may come from industrial and/or agricultural waste, while higher nitrate concentration might be a result of a septic tank leak and/or pesticide/fertilizer residue in paddy fields.

What We Know About Propolis, and Its Potential Role in Obesity and Diabetes

Propolis, a resinous, dark-colored product produced by honeybees has been gaining attention in terms of its multiple proven health benefits. This natural product has different types and varieties but close to similar chemical compositions according to the environment and location where it is produced, as well as its plant source. It is mainly composed of resinous, balsamic, and gummy materials, waxes and essential oils, and pollen from the plants. Propolis contains plenty of polyphenols and it’s a rich source of magnesium, calcium, iodine, potassium, sodium, copper, zinc, manganese, and iron as well as thiamin, riboflavin, vitamins B6, C, E, D, and provitamin A. It has been proven that propolis may help to reduce diet-induced obesity through its caffeic acid content. Studies proved the antibacterial, antiviral, anti-inflammatory, anticancer, antifungal, and antitumor effects of propolis and positive outcomes on diet-induced obesity, and diabetes. In this review, we aim to explain propolis extensively in terms of its types, chemical composition, bioactive compounds, digestion, health benefits on obesity and diabetes, as well as possible drug interactions, dosage, and safety.

Geochronology and skarn mineralogy of the Akesayi Fe deposit in the Western Kunlun, Xinjiang: Implications for mineralization process

The Akesayi deposit, located in the eastern part of the Tianshuihai terrane of the Western Kunlun Orogenic Belt, Xinjiang, China, is a recently discovered medium-sized magnetite deposit containing approximately 51 million tons of ore with an average grade of 41 wt%. This deposit is hosted by skarns at the contact between monzonitic granite, diorite porphyry, and medium to low-grade metamorphic clastic rocks of the Permian Huangyangling Group. The ore types include banded, disseminated, and massive ores. The metallogenic process can be divided into prograde skarn, retrograde skarn, oxide, quartz-sulfide, and carbonate stages. The metallic minerals include magnetite and pyrite, and the gangue minerals include olivine, garnet, hedenbergite, hornblende, actinolite, biotite, cummingtonite, chlorite, quartz, and calcite. The zircon U–Pb dating of biotite adamellite intrusion and schist together constrains the formation age of the host rocks in the Akesayi Fe deposit to 217–272 Ma. Rb–Sr dating of eight garnet samples yields an isochron age of 12.41 ± 0.31 Ma, which is almost identical to the 12.56 ± 0.50 Ma age obtained via Sm–Nd dating of eight garnet samples. Furthermore, zircon U–Pb dating yields ages of 12.76 ± 0.12 Ma and 12.37 ± 0.18 Ma for diorite porphyry and monzonitic granite near the Fe orebodies, respectively. The initial Sr isotopes of garnet ((87Sr/87Sr)i = 0.710901) prove that the diorite porphyrite ((87Sr/87Sr)i = 0.709283) is related to skarn mineralization. Thus, the Akesayi deposit is a skarn-type iron ore related to the middle Miocene diorite porphyry. The mineral assemblage indicates the extensive development of manganese-skarn in the Akesayi mining area. The manganese content of host rocks of the deposit is low, and the source of manganese in the skarn may mainly come from the hydrothermal fluids associated with Miocene diorite porphyry emplacement. The compositional variations between the cores and rims of single garnet grains and different stages of tephroite indicate the concentration characteristics of the hydrothermal system, particularly manganese content, which evidently changed during hydrothermal activity. The endmembers of garnet and pyroxene suggest that the ore-forming environment transformed from a relatively reduced acidic environment to an alkali-rich, high-oxygen fugacity environment. The widely developed chlorine-rich amphiboles and biotite indicate that the hydrothermal fluids were rich in chlorine and may have been related to the diorite porphyrite intrusion near the ore bodies. The iron mineralization of the Akesayi deposit is analogous to the Gangdese Miocene porphyry–skarn polymetallic mineralization, which occurred during the Miocene in a post-collisional tectonic setting. Considering the series of Miocene intrusives discovered in West Kunlun, we propose that Miocene skarn Fe mineralization events occurred in West Kunlun, and that this area has great prospecting potential.

Influences of five dietary manganese sources on growth, feed utilization, lipid metabolism, antioxidant capacity, inflammatory response and endoplasmic reticulum stress in yellow catfish intestine

Influences of five dietary manganese sources on growth, feed utilization, lipid metabolism, antioxidant capacity, inflammatory response and endoplasmic reticulum stress in yellow catfish intestine

Goose Meat as a Source of Dietary Manganese—A Systematic Review

Manganese is a trace element with essential physiological functions that should be supplied to animals and humans through diet. Goose meat is prevalent in many regions of the world. Therefore, the aim of the study was a systematic review (PRISMA statement, 1980-2022) of the content of Mn in raw and cooked goose meat and their relation to the recommended intake at the level of adequate intake (AI) and the nutrient reference values-requirements (NRV-R). The literature analysis shows that the content of Mn in goose meat depends on the breed, type of muscles, the presence of skin, and the cooking method used. AI level recommendations for Mn intake range from 0.003 to 5.50 mg/day, depending on the country, age, and gender. Consumption by adults (regardless of sex) of 100 g of domestic or wild goose meat covers the daily AI per Mn in various percentages, depending on the type of muscles (more Mn in leg muscles), presence of skin (more Mn in skinless muscles), and thermal treatment (pan fried with oil, grilled, and cooked meat contains more). Placing information on the Mn content in goose meat and the percentage of NRV-R on the packaging may be valuable information for the consumer in making food choices to diversify the diet. There are few studies on the content of Mn in goose meat. Therefore, it is reasonable to conduct research in this area.

A green repair pathway for spent spinel cathode material: Coupled mechanochemistry and solid-phase reactions

A way of directly repairing spent lithium-ion battery cathode materials is needed in response to environmental pollution and resource depletion. In this work, we report a green repair method involving coupled mechanochemistry and solid-state reactions for spent lithium-ion batteries. During the ball-milling repair process, an added manganese source enters into the degraded LiMn2O4 (LMO) crystal structure in order to fill the Mn vacancies formed by Mn deficiency due to the Jahn–Teller effect, thereby repairing the LMO's chemical composition. An added carbon source acts not only as a lubricant but also as a conductor to improve the material's electrical conductivity. Meanwhile, mechanical force reduces the crystal size of the LMO particles, increasing the amount of active sites for electrochemical reactions. Jahn–Teller distortion is successfully suppressed by cation disorder in the LMO material. The cycling stability and rate performance of the repaired cathode material are thereby greatly improved, with the discharge specific capacity being more than twice that of commercial LMO. The proposed solid-state mechanochemical in situ repair process, which is safe for the environment and simple to use, may be extended to the repair of other waste materials without consuming highly acidic or alkaline chemical reagents.

Environmental exposure to manganese and health risk assessment from personal sampling near an industrial source of airborne manganese

Manganese (Mn), despite being a trace element necessary in small quantities for the correct functioning of the organism, at higher concentrations can induce health disorders, mainly in motor and cognitive functions, even at levels found in non-occupational environments. For this reason, US EPA guidelines define safe reference doses/concentrations (RfD/RfC) for health.In this study, the individualised health risk of exposure to Mn through different media (air, diet, soil) and routes of entry into the organism (inhalation, ingestion and dermal absorption) was assessed according to the procedure defined by the US EPA. Calculations related to Mn present in ambient air were made on the basis of data obtained from size-segregated particulate matter (PM) personal samplers carried by volunteers recruited in a cross-sectional study conducted in the Santander Bay (northern Spain), where an industrial source of airborne Mn is located.Individuals residing in the vicinity of the main Mn source (within 1.5 km) were found to have a hazard index (HI) higher than 1, indicating that there is a potential risk for these subjects to develop health alterations. Also, people living in Santander, the capital of the region, located 7–10 km from the Mn source, may have some risk (HI > 1) under some wind conditions (SW). In addition, a preliminary study of media and routes of entry into the body confirmed that inhalation of PM2.5-bound Mn is the most important route contributing to the overall non-carcinogenic health risk related to environmental Mn.