High Iron Content Research Articles

Perspectives for improving deironing technologies groundwater for local drinking systems

In order to provide the population with high-quality drinking water, it is more expedient to focus on the use of underground sources of water supply, which are better protected from pollution in comparison with surface waters. However, a significant part of the underground sources of water supply is characterized by a high iron content, and the water from them needs to be deironed before being supplied to consumers. Removal of excessive iron content from underground water can be carried out by reagent or reagent-free methods, using water deiron installations of various design schemes and resorting to measures that increase the efficiency of their work. On the basis of the analysis of existing technologies for removing iron from groundwater and modern trends in the field of water purification, it is proposed for local water supply systems to use a filter with an automatic control valve and a technology that provides for reagent-free iron removal of groundwater due to the oxidation of dissolved iron with air cushion oxygen and further detention of the sediment formed in the layer of the multicomponent filter load. This technology is characterized by low cost and wear resistance of natural filter materials, ease of operation, environmental friendliness, which excludes secondary contamination of purified water with reagents, compactness and automation of control processes, which is especially relevant for small settlements.

Formation of Apoplastic Barriers to Radial O₂ Loss in Rice Roots: Effects of Low-O₂ and High-Fe Conditions, and the Roles of Suberin, Glycerol Esters, and Iron Plaques.

Lack of O2 and high concentrations of iron (Fe) are common in flooded soils where Rice (Oryza sativa L.) is cultivated. We tested the hypothesis that growing in stagnant or high Fe conditions might induce the formation of apoplastic barriers in roots with different properties and chemical compositions. We measured radial O2 loss (ROL) from intact roots, the chemical composition of roots and the formation of root iron plaques in Fe-sensitive and Fe-tolerant rice genotypes grown in aerated, deoxygenated stagnant solutions or in aerated solutions containing high concentrations of Fe. Roots of plants grown in stagnant conditions developed tight barriers to ROL, while those grown in high Fe conditions developed only partial barriers. Chemical analysis of enzymatically isolated sclerenchyma/exodermal root cells indicated that roots grown in stagnant conditions showed increased amounts of suberin and glycerol esters. In contrast, roots in high Fe conditions showed an increase in suberization along with formation of iron plaques covering the roots. In high Fe conditions, exodermal suberization and the formation of partial ROL barriers were not influenced by the genotype's tolerance to Fe. The amount of O2 diffused from roots is influenced by the various layers that impede O2 diffusion. Specifically, increased amounts of glycerol esters in the suberized exodermis provide the greater resistance to ROL.

Structural, Optical, Magnetic and Electrical Properties of Zinc Oxide Doped with Iron: A Review

This study reviewed the structural, optical, magnetic and electrical properties of zinc oxide (ZnO) nano-particles doped with iron relative to zinc oxide. ZnO is an excellent nanomaterial in semiconductor industries because of its properties such as low cost, high stability and high absorbance. However, its application has been limited because of some undesirable characteristics. Hence, doping with iron has proven essential in overcoming these limitations. The X-ray diffraction studies show that the structure is hexagonal with wurtzite structure, ZnO films prefer to grow in the (002) direction. This is because each apex is parallel to the c-axis in the wurtzite structure. This review reported that optical band gap ZnO nano-particles doped with iron was found to be in the range to (3.26 - 3.35) eV. The electrical properties of these films indicated low resistivity and consequently high electrical conductivity at high dopant iron concentration. Consequently, higher electrical resistivity was observed with lower conductivity at lower iron dopant concentration. Higher iron-doped ZnO (x=0.10 and 0.20) samples exhibited obvious ferromagnetic behaviors suggesting that saturation magnetization of Zn1-xFexO nano-particles increases with the increasing of Fe doping concentration compared with pure ZnO. Hence the SEM of iron-doped zinc oxide nano-particles consists of ellipsoidal shape particles, which are well dispersed with smooth surface and uniform size.

Structural Analysis of Variants of the Ferritin Light Chain Protein and Its Relationship with Neuroferritinopathy.

Ferritin is a highly conserved spherical protein that stores iron and possesses triple and quadruple symmetry input ports. Additionally, it is composed of light chains that can be affected by post-translational mutations, reducing the iron storage capacity in the brain and leading to neuroferritinopathy, which is a rare disease with limited bioinformatics data. In this study, we analyzed the biochemical mechanism of different ferritin mutations reported in the literature, through the characterization and determination of the in silico structural model by searching databases, implementing bioinformatics programs such as Jalview, NetNGlyc 1.0, NetOGlyc 3.1, and three-dimensional structure predictors with machine learning such as Alphafold, demonstrating the generation of hairpin and steric hindrances that hinder the aggregation of subunits and changes in the size and arrangement of quadruple and triple entry holes of the A96T mutation compared to the wild-type protein, since in the quadruple entry hole, a decrease in area is observed compared to the wild-type protein and the triple entry hole has a decrease in distance measurements of 6.504 Å. This possibly affects the functionality of the protein, thus releasing high concentrations of iron in the brain and causing neurodegeneration.

Detection of Laterite Nickel Layer Distribution Based on Correlation of Multispectral Remote Sensing and Magnetic Satellite Data in North Konawe Region, Southeast Sulawesi

Abstract The demand for nickel continues to rise as an essential raw material to produce stainless steel and other metal alloys. Nickel deposits are abundant in Sulawesi Island due to their close association with tectonic plate movements. Therefore, this research aims to detect the distribution of laterite nickel based on the correlation of multispectral remote sensing and magnetic satellite methods in area X, North Konawe, Southeast Sulawesi. The remote sensing analysis utilized Landsat 8 with the combination of 6/5 band ratio to identify iron (Fe) and a 4/7 band ratio to detect quartz-bearing layers. Meanwhile, magnetic satellite data was obtained from The National Oceanic and Atmospheric Administration website with a total of 314 data. Based on the research results, there is a correlation between the two methods and geological mapping data where the iron (Fe) content in the limonite zone is dominant in the research area. The multispectral remote sensing analysis identified areas with high iron (Fe) content, which were further supported by magnetic satellite data showing magnetic anomalies from −0.312 to 0.178 nT. High anomalies within this range, particularly those between 0.004 and 0.178 nT, are indicative of layers rich in iron (Fe) within the limonite zone, thereby confirming the presence of laterite nickel deposits in the study area.

Improving Iron Content in Sustainable Mycoprotein Production through Seawater Fermentation

The growing global population and rising protein demand are straining freshwater resources. Fusarium venenatum (Fv) mycoprotein offers a sustainable protein alternative, with environmental efficiency and potential health benefits. However, its low iron content remains a concern, especially for vegetarians and vegans. This study introduces a sustainable approach, employing seawater as a fermentation medium for Fv production. Our analysis reveals that mycoprotein derived from SEA Fv exhibits elevated levels of sodium and calcium, with a notably high iron content (2.2 mg/100g wet weight). The sodium content, while 3.31 times higher than in non-seawater fermentation, remains within recommended daily intake parameters. No plasticizers or heavy metals were detected in the SEA Fv cell body, minimizing long-term toxicity risks from seawater use. A unique metabolite, dihydroorotic acid, was identified from an in-house library of 774 metabolites, serving as an internal biomarker for seawater-based production methods. An acute safety study condensing 600g of SEA Fv to simulate high mycoprotein digestion showed no effects on key physical behaviors or major organs, including the heart and lungs. This positions the product as a viable protein alternative with enhanced iron content, highlighting seawater-based fermentation as a sustainable method for future food production and industry progress.

Atmospheric air pollution from the Ermakovskoe fluorite-beryllium deposit development waste

Relevance. Negative impact of waste from mining enterprises on the ecological state of the surrounding areas. Aim. To determine the migration ability of toxic chemical elements from waste storage sites of the Ermakovskoe beryllium deposit in the air. Object. Ermakovskoe fluorite-bertrandite-phenacite deposit and the surrounding area. Methods. Inductively coupled plasma mass spectrometry, laser diffraction, inductively coupled plasma atomic emission spectrometry. Results and conclusions. The paper introduces the experimental studies of surface atmospheric pollution by mining waste from the Ermakovskoe fluorite-bertrandite-phenakite deposit are presented using an installation for collecting aerosols above the sand surface. It was established that toxic components formed during the decomposition of residual sulfide mineralization and products of the interaction of acidic waters with rocks move from the sand thickness to the surface along with water vapor. The moisture condensed over the sand contains high contents of aluminum, iron, manganese, zinc, and phosphorus. These elements form a halo of air pollution over mining waste and are then dispersed by air currents into the surrounding area. In winter, due to wind dispersion of aerosols, the snow cover becomes contaminated over a vast area. Among the toxic elements found were beryllium, lead, cadmium, and molybdenum, which belong to the second hazard class. The solid residue of the snow cover contains a fine fraction of dust, the size of which is less than 10 microns. The halo of snow contamination with toxic chemical elements and dust extends several kilometers away from the disturbed lands.

Characterization and Processing of Low-Grade Middle Group 2 Chromite Ore by Gravity Shaking Table and a Comparative SLon Magnetic Separation: A Case Study

Chromite is considered a strategic mineral in the global economy. It is mainly used as an essential raw material in the production of stainless steel and other metal alloys due to its corrosion and heat resistance properties. High-grade chromite resources are gradually depleting; with the increasing chromite demand in metallurgical applications, studies have focused on exploring low-grade and alternative chromite sources. This study proposes a cost-effective processing flowsheet for the low-grade middle group 2 (MG2) chromite layer, a poorly explored chromatite seam within the South African bushveld igneous complex (BIC). The study involved mineralogical characterization followed by gravity and magnetic separation of the low-grade MG2 ore at 18.18% Cr2O3. Characterization by XRD and Auto-SEM revealed that the ore mainly consists of pyroxene, chromite, and feldspar, with other minerals in trace quantities. The gravity separation test by shaking table upgraded the chromite (Cr2O3) to 42.0% at high chromite recoveries, whereas the laboratory Slon wet high-intensity magnetic separation method (SLon WHIMS) upgraded the chromite in the feed to 42.95% grade at lower chromite recoveries. Desliming the sample before the gravity and magnetic separation tests significantly improved the separation. The magnetic separation tests further demonstrated that chromite within the MG2 layer is sensitive to magnetic separation due to its high iron content. The adapted flowsheet is proposed as a cost-effective flowsheet for processing the low-grade MG2 layer. The flow sheet can be optimized by conducting the SLon WHIMS tests at high intensities followed by fine gravity tests by spiral circuits to maximize the chromite recovery while achieving commercial chromite grades and a Cr:Fe ratio greater than 1.5.

Effect of Iron Contamination and Polysilicon Gettering on the Performance of Polysilicon‐Based Passivating Contact Solar Cells

ABSTRACTOver the past decade, silicon solar cells with carrier‐selective passivating contacts based on polysilicon capping an ultra‐thin silicon oxide (commonly known as TOPCon or POLO) have demonstrated promising efficiency potentials and are regarded as an evolutionary upgrade to the PERC (passivated emitter and rear contact) cells in manufacturing. The polysilicon‐based passivating contacts also exhibit excellent gettering effects that relax the wafer and cleanroom requirements to some extent. In this work, we experimentally explore the impact of bulk iron contamination and polysilicon gettering on the passivation quality of the polysilicon/oxide structure and the resulting solar cells performance. Results show that both n‐ and p‐type polysilicon/oxide passivating contacts are not affected by iron gettering, demonstrating robust and stable passivation quality. However, for a very high bulk iron contamination (1 × 1013 cm−3), the accumulated iron in the p‐type lightly boron‐doped emitter in crystalline silicon would degrade the emitter saturation current density. This can cause a reduction in both open‐circuit voltage and short‐circuit current. Meanwhile, this very high iron content (1 × 1013 cm−3) can further degrade the fill factor and temperature coefficient of the cells. On the other hand, for an initial iron content of 2 × 1012 cm−3, which should be well above the iron level in the current industrial Czochralski silicon wafers, the resulting cells demonstrate similar performance as the control group with no intentional iron contamination. This work brings attention to both the benefits of polysilicon gettering effects as well as the potential degradation due to the accumulation of metal impurities in the p‐type emitter region.

Sono-photo-Fenton action is improved by the addition of Passiflora edulis f. flavicarpa Degener (yellow passion fruit).

The improvement of the sono-photo-Fenton process at nearby neutral pH (~ 6.2) and high iron concentration (5mg L-1) by the addition of the juice of Passiflora edulis f.flavicarpa Degener (yellow passion fruit) on the degradation of imipenem in water is reported for the first time. Considering that the combination of sonochemistry with photo-Fenton takes advantage of the in situ sonogeneration of H2O2, the effects of frequency and acoustic power for the H2O2 accumulation were established initially. The sonication at 578kHz and 23.8 W favored the H2O2 generation. Using such frequency and power, the antibiotic was synergistically degraded by the sono-photo-Fenton system in distilled water, leading to ~ 90% removal at 120min of treatment. An atomic charge analysis showed that thioether, β-lactam ring, and carboxylic acid moieties on the imipenem structure were very prone to interactions with the HO• generated in the sono-photo-Fenton process. Indeed, the primary transformation products (TPs) came from the oxidation of the thioether, the opening of the β-lactam ring, and decarboxylations. Such TPs had a lower probability than imipenem to be active against bacteria. Besides, the addition of small amounts (2.5-10 µL) of the yellow passion fruit juice to the sono-photo-Fenton system significantly improved the pharmaceutical elimination. However, a juice excess (e.g., 100 µL) caused a detrimental effect due to competing effects by radicals. The juice of the yellow passion fruit induced analogous effects to citric acid (a commercial complexing agent) on the sono-photo-Fenton process. Indeed, the degradation of imipenem in simulated hospital wastewater by sono-photo-Fenton was improved by the yellow passion fruit juice (~ 38% at 60min), and it was similar to that with citric acid (~ 39% of removal at 60min). Thus, the commercial reagent can be replaced by a natural and low-cost complexing agent (e.g., yellow passion fruit juice or fruit wastes containing citric acid), as an enhancer of the sono-photo-Fenton process carried out at near-neutral pH and high iron concentration for degrading imipenem in water.

Nutritional and Phytochemical Profile of Commonly Consumed Spices in Nigeria

Background: Spices which are widely used in Nigeria have aroma, enhance taste of food and Possess medicinal values. Objectives: This study aimed to determine the nutritionaland phytochemical profile of commonly consumed spices in Nigeria. Materials and Methods: Raw materials and other ingredients used for this study were purchased from Oja-Oba in Owo Local Government, Ondo State. The spices were analysed for proximate and mineral components using standard method as described by AOAC (2012). Sodium and potassium were determined using flame photometer and calcium, selenium, copper, zinc, magnesium, and iron were determined using atomic absorption spectrophotometer. Phytochemical analyses were carried out using standard procedures. Results: The proximate composition showed that protein was significantly (p≤0.05) high at 14.41% in Uziza seed and low at 11.60% in tumeric. Ginger contained high moisture content at 10.63%, while Uziza seed had the least value of 8.58%. High ash content was recorded in gingerat 5.27% and lowest at 3.70% in Uziza. Tumeric had the highest value of 65.57% for carbohydrate, while Uziza had the least value of 60.06%. Mineral composition showed high value of calcium in Uziza seed (402.03mg/100g). Nutmeg showed a high value of magnesium (13.3mg/100g) and turmeric indicated the highest value of potassium (405.43mg/100g), sodium (135.17mg/100g) for Uziza seed. The highest content of iron was recorded at 3.34mg/100g. Turmeric had a high value of zinc at 3.77 mg/100g and copper at 97 mg/100g, respectively. The spices contained an appreciable amount of phytochemicals. However, turmeric was significantly higher in alkaloids, flavonoids and polyphenols. Conclusion:This study showed that spices have greater use in medicine and as a food supplement.

Iron Content in Wild Animal Meats: A Systematic Review Comparing Mammals and Birds

This study explores the iron content in wild animal meats, a critical component of the diets of several Indigenous Peoples and Local Communities (IPLC) worldwide. Our research aimed to: (i) characterize the iron content in the muscles and viscera of wild mammals and birds, and (ii) assess whether wild bird muscle contains less iron than wild mammal muscle. Employing a systematic literature review guided by PRISMA standards and utilizing databases such as Web of Science, Medline/PubMed, and Scopus, we analyzed data from eight pertinent studies. No data regarding bird viscera were identified. Our findings indicate a significant disparity in iron content between the viscera and muscle of mammals, with the former exhibiting over six times the iron content (mean of 15.25 mg per 100g) compared to the latter (mean of 2.24 mg per 100g). Contrary to our hypothesis, the iron content in the muscles of birds (mean of 3.75 mg per 100g) and mammals did not significantly differ (p=0.120), with birds, descriptively, demonstrating a nearly 70% higher iron content. This unexpected result may be attributed to the influence of slaughter methods, such as gunshot, which prevents external bleeding, or animal behavior. Our research underscores the necessity of considering slaughter techniques in nutritional assessments of meat. These findings not only contribute to our understanding of nutritional values of wild meat but also prompt further investigation into their role in human diets, especially among IPLC.

Formation of Ferrogabbro Through Fe-Ti Oxide Accumulation Under Moderate Oxidation Conditions: Insights from the Dashanshu Intrusion in the Emeishan Large Igneous Province, SW China

The mechanism of iron enrichment in ferrogabbro remains a controversial subject. This study provides valuable insights derived from the Dashanshu intrusion, located in the Emeishan Large Igneous Province in southwestern China, which features ferrogabbro with a notably high iron content (total Fe2O3 reaching up to 21.6 wt.%). The ferrogabbro samples exhibit distinctive petrographic features, including the early crystallization of plagioclase prior to pyroxenes, amphibole replacing pyroxenes, and magnetite–ilmenite intergrowth filling the interstices between plagioclase and pyroxenes. A quantitative mineral analysis based on micro-X-ray fluorescence element mapping reveals a positive correlation between Fe-Ti oxides and bulk-rock iron contents, suggesting that the formation of ferrogabbro is primarily attributed to the accumulation of Fe-Ti oxides. Petrographic characteristics combined with oxygen fugacity determinations indicate that the primitive magma had a low content of water and was moderately oxidized (ΔFMQ − 0.13 to ΔFMQ + 1.35). These conditions suppress the early crystallization of Fe-Ti oxides, thereby allowing for an enrichment of iron in the residual magma. Following the crystallization of plagioclase and pyroxenes, increased water content—evidenced by amphibole replacing pyroxenes—triggers extensive crystallization of Fe-Ti oxides. Due to their late-stage crystallization, these oxides do not settle within the magma, which possesses a high crystallinity (>50%) and consequently exhibits non-Newtonian fluid behavior. This results in the localized accumulation of Fe-Ti oxides and the formation of a ferrogabbro layer. However, the late-stage crystallization of Fe-Ti oxides also impedes the sinking and flow-sorting processes that are essential for the development of economically valuable Fe-Ti oxide layers. This may account for the lack of an economically valuable Fe-Ti oxide layer within the Dashanshu intrusion.

Iron fortification modifies the microbial community structure and metabolome of a model surface-ripened cheese

Iron is a vital micronutrient for nearly all microorganisms, serving as a co-factor in critical metabolic pathways. However, cheese is an iron-restricted environment. Furthermore, it has been demonstrated that iron represents a growth-limiting factor for many microorganisms involved in cheese ripening and that this element is central to many microbial interactions occurring in this ecosystem. This study explores the impact of iron fortification on the growth and activity of a reduced microbial community composed of nine strains representative of the microbial community of surface-ripened cheeses. Three different iron compounds (ferrous sulfate, ferric chloride, ferric citrate) were used at three different concentrations, i.e., 18, 36, and 72 μM, to fortify cheese curd after inoculation with the consortium. This treatment significantly enhanced the growth of certain cheese-ripening bacteria in curd, resulting in substantial changes in the volatilome and metabolome profiles. These observations were dose-dependent, with more pronounced effects detected with higher iron concentrations. No statistically significant difference was observed in the microbial composition based on the iron compounds used for fortification, but this factor had an impact on the volatilome and amino acids profile. These findings highlight the importance of iron availability for the behavior of cheese microbial communities. They also open novel perspectives on cheesemakers' use of iron fortification to control microbial growth and improve cheese quality.

SNP alleviates ferric and salt stress in Phaseolus vulgaris seeds

Seed germination and early development are delicate events often influenced by various environmental factors. Among these factors, the accumulation of salts and heavy metals in the soil is noteworthy. This study aimed to observe the effect of priming with solutions of sodium nitroprusside, polyethylene glycol 6000, and potassium nitrate on the germination of Phaseolus vulgaris seeds exposed to toxic conditions of iron and sodium chloride. Seeds were germinated on plates placed in a growth chamber at a constant temperature of 25°C and a 12-hour photoperiod. The percentage of germination, germination speed, root and shoot lengths, catalase, peroxidase activities, and malondialdehyde content were evaluated. Exposure to high concentrations of sodium chloride and iron reduced germination percentage, germination speed, root and shoot lengths of treated plants. Only sodium nitroprusside treatment mitigated the effects of stressors. No increase in malondialdehyde content was observed in any treatment, suggesting no lipid peroxidation of membranes. However, all treatments showed increased catalase activity, possibly indicating oxidative stress and metabolic damage. Sodium nitroprusside stands out as a stress alleviator for sodium chloride and iron accumulation during the germination phase.

Ragi Revolution: Enhancing Dietary Practices through Nutritional Education and Local Food Systems Implementation

Ragi (Eleusine coracana), commonly known as finger millet, is a nutrient-rich cereal that remains underutilized in modern diets despite its high calcium, iron, and dietary fiber content. This examines how ready-to-eat ragi-based supplementary foods, combined with effective nutrition education, can drive behavioral changes to incorporate ragi into daily diets and local food systems. The increasing availability of ready-to-eat ragi products offers an accessible solution for improving nutrition, but challenges remain in terms of consumer acceptance due to unfamiliarity and taste preferences. This paper focuses on the role of nutrition education in reshaping dietary behaviour, emphasizing case studies that demonstrate the effectiveness of targeted interventions in promoting ragi consumption. Additionally, it explores strategies for integrating ragi into public nutrition programs and sustainable food systems, highlighting the importance of community-driven efforts and public-private partnerships. The review also discusses the role of policy support and multi-stakeholder collaboration in fostering ragi’s cultivation and incorporation into local food systems. By examining behavioural change strategies such as social marketing and culturally sensitive approaches, this paper presents a roadmap for promoting ragi as a key component of sustainable diets and public health interventions.

Sludge from Arapaima Gigas Culture as an Alternative Culture Medium for Lipid Production in Nannochloropsis Sp

Objective: The objective of this work was to evaluate the use of sludge generated during the culture of Arapaima gigas as an alternative medium for Nannochloropsis sp. Theoretical Framework: Microalgae are photosynthetic micro-organisms with the ability to transform organic waste or effluents into valuable biomass. They are currently of great interest for their use in the food and pharmaceutical industry. Nannochloropsis sp. is a valuable microalga due to its excellent lipid profile. Method: The sludge used was collected from A. gigas culture ponds at the CITE Acuícola Pesquero Ahuashiyacu (Tarapoto-Peru). An aqueous extract of sludge (EAL) was obtained from the sample by a thermal procedure, which was dosed into the cultures at concentrations of 100, 150 and 200 mL/L. The experimental units followed the traditional batch culture arrangement under laboratory conditions. Guillard F/2 medium was used as control treatment. The characterisation of metals in the medium was performed by coupled plasma induction (ICP) and the determination of ammonium and nitrite by colorimetric tests. In addition, population density, productivity and total lipid content were estimated. Results and Discussion: Chemical analyses revealed high concentrations of calcium, sodium, magnesium, iron, potassium, phosphorus, ammonium and nitrite (655, 648, 283, 67, 32, 17, 1.5, and 10 ppm, respectively). Likewise, the best growth (3590.00 ± 91.24 x 104 cells/mL) and productivity (0.69 ± 0.01 g/L) was obtained with 200 mL/L of EAL, presenting significant statistical differences (p < 0.05) with respect to the other treatments. In contrast, the highest lipid production (29.67 ± 1.53 %) was observed in the control treatment, far exceeding the EAL cultures; however, no significant statistical difference was observed between EAL treatments. Research Implications: These results demonstrate the feasibility of using EAL as an alternative medium for the production of Nannochloropsis sp. with a positive environmental and economic impact on the production of A. gigas. Originality/Value: The use of sludge generated in fish culture, in particular A. Gigas, has not been reported previously. In this study, we demonstrate for the first time the feasibility of using this sludge in the culture of the microalga Nannochloropsis sp. which also has a high potential for use in fish larviculture.

Nutritional Glutamine-Modified Iron-Delivery System with Enhanced Endocytosis for Ferroptosis Therapy of Pancreatic Tumors.

Heterogeneous reprogrammed nutrient metabolic networks formed by oncogenes exhibit the potential for exploring novel druggable targets and developing innovative anticancer therapeutics. Herein, based on the heterogeneous metabolic characteristics of glutamine (Gln) addiction in pancreatic cancer cells, an iron-delivery system (IDS) with enhanced endocytosis is designed for efficient ferroptosis therapy. The IDS is characterized by Gln modification and can be recognized as a source of Gln nutrients for efficient endocytic uptake by pancreatic tumor cells. Because the IDS is flexible to combine with amino acid-like components, the IDS with enhanced endocytosis is further produced by loading the Gln transporter inhibitor of V9302. V9302 is capable of suppressing molecular Gln uptake via transporter ASCT2, which generates Gln deprivation to direct metabolic reprogramming of cancer cells and enhances cellular uptake of Gln-modified IDS via RAS-stimulated macropinocytosis. The enhanced endocytosis and high iron content of IDS facilitate ferroptosis in mice pancreatic tumor models; thus, an amino acid-like ferroptosis inducer of l-buthionine sulfoximine (BSO) is further combined. The enhanced endocytosis resulting from the synergism of Gln and V9302 enables the efficient delivery of iron and BSO for ferroptosis tumor therapy. This work provides an alternative approach for enhancing intracellular drug delivery of the tumors with heterogeneous nutrient metabolism by virtue of combining nutrient-modified nanodrugs with the corresponding nutrient transporter inhibitors.

Reactivation of MAPK-SOX2 pathway confers ferroptosis sensitivity in KRASG12C inhibitor resistant tumors

The clinical success of KRASG12C inhibitors (G12Ci) including AMG510 and MRTX849 is limited by the eventual development of acquired resistance. A novel and effective treatment to revert or target this resistance is urgent. To this end, we established G12Ci (AMG510 and MRTX849) resistant KRASG12C mutant cancer cell lines and screened with an FDA-approved drug library. We found the ferroptosis inducers including sorafenib and lapatinib stood out with an obvious growth inhibition in the G12Ci resistant cells. Mechanistically, the G12Ci resistant cells exhibited reactivation of MAPK signaling, which repressed SOX2-mediated expression of cystine transporter SLC7A11 and iron exporter SLC40A1. Consequently, the low intracellular GSH level but high iron content engendered hypersensitivity of these resistant tumors to ferroptosis inducers. Ectopic overexpression of SOX2 or SLC7A11 and SLC40A1 conferred resistance to ferroptosis in the G12Ci resistant cells. Ferroptosis induced by sulfasalazine (SAS) achieved obvious inhibition on the tumor growth of xenografts derived from AMG510-resistant KRASG12C-mutant cells. Collectively, our results suggest a novel therapeutic strategy to treat patients bearing G12Ci resistant cancers with ferroptosis inducers.

Effects of Bacillus spp. inoculation on suggested shoot tolerance mechanisms in lowland rice (Oryza sativa L.) grown under iron toxicity

AbstractBackgroundIn areas of lowland rice production, high iron concentrations in the soil often lead to yield reductions. Local adapted varieties possess different adaptation mechanisms, which, however, are not fully understood. Previous studies have shown that endophytic bacteria can influence plant tolerance to abiotic stresses, including iron toxicity.AimThis study aims at analyzing the effects of different Bacillus isolates on distinct shoot tolerance mechanism in different rice cultivars grown under iron toxicity.MethodsThree lowland rice cultivars, varying in their tolerance against iron toxicity (IR31785‐58‐1‐2‐3‐3, Sahel 108, Suakoko 8), were inoculated with three Bacillus strains (two of B. pumilus and one of B. megaterium). One week after Bacillus inoculation plants were subjected to high iron levels (1000 ppm) for 7 days. Leaf symptom scoring was used to assess tolerance levels. Activities of ascorbate peroxidase (APX), glutathione reductase (GR), catalase (CAT), superoxide dismutase (SOD), and guaiacol peroxidase (PRX) were measured by spectrophotometric assays. Transcription of genes related to iron toxicity (OsFER, OsFRO1, OsNRAMP6) was determined by RT‐qPCR. Bacterial production of NO was evaluated by measuring nitrite levels in the culture supernatants.ResultsIn general, iron toxicity affected the activities of APX, GR, CAT, and PRX but not SOD activity. Only PRX activity in response to iron differed between cultivars with a significantly stronger increase in IR31785‐58‐1‐2‐3‐3. Inoculation with B. pumilus Ni9MO12 led to higher activity of CAT in the leaf sheaths of all cultivars and an increase in GR activity in the sheaths that was significantly higher in Suakoko 8. In the young leaf blades of IR31785‐58‐1‐2‐3‐3, transcription of OsFRO1 and OsNRAMP6 was not significantly affected by Bacillus inoculation, whereas accumulation of OsFER mRNA was significantly higher in iron‐stressed, B. pumilus Ni9MO12 inoculated plants compared to non‐inoculated, non‐iron‐stressed plants. Nitrite concentration as an indicator for NO production was increased in B. pumilus Ni9MO12 culture supernatants.ConclusionOur results show that in the sensitive cultivar IR31785‐58‐1‐2‐3‐3 tolerance to iron toxicity increases when inoculated with B. pumilus Ni9MO12, coinciding with higher levels of ferritin transcription. NO production by the Bacillus isolate might confer the promotion of OsFER gene transcription in the inoculated plants.