Unique regulatory network of dragon fruit simultaneously mitigates the effect of vanadium pollutant and environmental factors.

Under changing climatic conditions, plants are simultaneously facing conflicting stresses in nature. Plants can sense different stresses, induce systematic ROS signals, and regulate transcriptomic, hormonal, and stomatal responses. We performed transcriptome analysis to reveal the integrative stress response regulatory mechanism underlying heavy metal stress alone or in combination with heat and drought conditions in pitaya (dragon fruit). A total of 70 genes were identified from 31,130 transcripts with conserved differential expression. Furthermore, weighted gene co-expression network analysis (WGCNA) identified trait-associated modules. By integrating information from three modules and protein-protein interaction (PPI) networks, we identified 10 interconnected genes associated with the multifaceted defense mechanism employed by pitaya against co-occurring stresses. To further confirm the reliability of the results, we performed a comparative analysis of 350 genes identified by three trait modules and 70 conserved genes exhibiting their dynamic expression under all treatments. Differential expression pattern of genes and comparative analysis, have proven instrumental in identifying ten putative structural genes. These ten genes were annotated as PLAT/LH2, CAT, MLP, HSP, PB1, PLA, NAC, HMA, and CER1 transcription factors involved in antioxidant activity, defense response, MAPK signaling, detoxification of metals and regulating the crosstalk between the complex pathways. Predictive analysis of putative candidate genes, potentially governing single, double, and multifactorial stress response, by several signaling systems and molecular patterns. These findings represent a valuable resource for pitaya breeding programs, offering the potential to develop resilient "super pitaya" plants.

Emulsion liquid membrane (ELM) enhanced by nanoparticles and ionic liquid for extracting vanadium ions from wastewater.

Emulsion liquid membrane (ELM) stands out as an extraction process that has drawn much attention due to its promising prospects in industrial wastewater treatment technology. Nevertheless, the pivotal challenge is to reach high membrane stability to overcome the obstacle of applying ELM at the industrial scale. In this study, ELM was boosted by using nanoparticles (superparamagnetic iron oxide (Fe2O3)) in the stripping phase (W1) and ionic liquid (1-methyl-3-octyl-imidazolium-hexafluorophosphate [OMIM][PF6) in the oil phase (O) for recovering/extracting vanadium from synthetic wastewater to near completion and at the same time enhancing emulsion stability to be appropriate for industrial application. The vanadium recovery/extraction percentage has been raised significantly in 3 min to 99.6% when adding 0.01% (w/w) Fe2O3 NPs (20 to 50 nm in size) in the internal phase (W1) and 5% (v/v) [OMIM]PF6 ionic liquid in the oil phase (O). Also, the emulsion stability was considerably improved, and the leakage percentage was reduced to 16% after 3 days. The results of this study could be used in the future to remove additional heavy metal ions from industrial effluents.

Biomimetic synergistic effect of redox site and Lewis acid for construction of efficient artificial enzyme.

In enzymatic catalysis, the redox site and Lewis acid are the two main roles played by metal to assist amino acids. However, the reported enzyme mimics only focus on the redox-active metal as redox site, while the redox-inert metal as Lewis acid has, to the best of our knowledge, not been studied, presenting a bottleneck of enzyme mimics construction. Based on this, a series of highly efficient MxV2O5·nH2O peroxidase mimics with vanadium as redox site and alkaline-earth metal ion (M2+) as Lewis acid are reported. Experimental results and theoretical calculations indicate the peroxidase-mimicking activity of MxV2O5·nH2O show a periodic change with the Lewis acidity (ion potential) of M2+, revealing the mechanism of redox-inert M2+ regulating electron transfer of V-O through non-covalent polarization and thus promoting H2O2 adsorbate dissociation. The biomimetic synergetic effect of redox site and Lewis acid is expected to provide an inspiration for design of enzyme mimics.

Synthesis and Characterization of Vanadium Nitride/Carbon Nanocomposites.

The present work focuses on the synthesis of a vanadium nitride (VN)/carbon nanocomposite material via the thermal decomposition of vanadyl phthalocyanine (VOPC). The morphology and chemical structure of the synthesized compounds were characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), Fourier transformed infrared spectroscopy (FTIR), X-ray diffraction (XRD), and X-ray photoemission spectroscopy (XPS). The successful syntheses of the VOPC and non-metalated phthalocyanine (H2PC) precursors were confirmed using FTIR and XRD. The VN particles present a needle-like morphology in the VN synthesized by the sol-gel method. The morphology of the VN/C composite material exhibited small clusters of VN particles. The XRD analysis of the thermally decomposed VOPC indicated a mixture of amorphous carbon and VN nanoparticles (VN(TD)) with a cubic structure in the space group FM-3M consistent with that of VN. The XPS results confirmed the presence of V(III)-N bonds in the resultant material, indicating the formation of a VN/C nanocomposite. The VN/C nanocomposite synthesized through thermal decomposition exhibited a high carbon content and a cluster-like distribution of VN particles. The VN/C nanocomposite was used as an anode material in LIBs, which delivered a specific capacity of 307 mAh g-1 after 100 cycles and an excellent Coulombic efficiency of 99.8 at the 100th cycle.

Performance of V-Fe based catalysts on the oxidation of dibenzothiophenes.

To obtain fossil fuels with ultra-low S levels at friendly conditions, different V oxides formulations on alumina modified with Fe were characterized and selected to oxidize dibenzothiophene (DBT), 4-methyl DBT and 4,6-dimethyl DBT prevailing in diesel fuel. V-Fe based catalysts (5 or 10 wt% of V) were obtained by impregnation of ammonium metavanadate solutions on Fe-modified alumina, obtained by impregnation of Mohr salt on pseudoboehmite (2 wt% of Fe). The catalysts were calcined in air atmosphere, and after were partially reduced with H2 flux to obtain a mix of several oxidation states of V and Fe species, to evaluate the interaction of Fe in VOx/Al2O3 catalysts and determine its effect on the oxidation processes. The structural and optical properties, as well as surface species, were determined by SEM-EDS, TPR, XRD, Raman, ATR-FTIR, photoluminescence, UV-Vis diffuse reflectance, and XPS spectroscopy. The catalytic performance was evaluated in oxidative desulfurization (ODS) and photocatalytic ODS (PODS) processes. The experimental results showed the addition of Fe promoted the catalytic activity of both ODS and PODS reactions. ODS activities of V-Fe catalysts increase up to 7.5 times with respect to V catalysts without Fe, and the most active catalyst (V5Fer) presents a characteristic oxidation time of 50 min for 4,6-DMDBT. The PODS activity of V10Fec was like ODS activity, showing it is possible to oxidize the dibenzothiophenes under friendly conditions to obtain lower S levels. The promoting effect of Fe was due to the interaction of Fe2+ and Fe3+ with the catalytic support, favoring the distribution of surface V3+ and V4+ species. Additionally, Fe improved the optical properties of the catalysts since the bandgap energy decrease and low recombination rate of the electron-hole pair were observed. Therefore, V-Fe based catalysts are photocatalytically actives to be used in PODS processes.

Vanadium haloperoxidases as noncanonical terpene synthases.

Vanadium-dependent haloperoxidases (VHPOs) are a unique family of enzymes that utilize vanadate, an aqueous halide ion, and hydrogen peroxide to produce an electrophilic halogen species that can be incorporated into electron rich organic substrates. This halogen species can react with terpene substrates and trigger halonium-induced cyclization in a manner reminiscent of class II terpene synthases. While not all VHPOs act in this capacity, several notable examples from algal and actinobacterial species have been characterized to catalyze regio- and enantioselective reactions on terpene and meroterpenoid substrates, resulting in complex halogenated cyclic terpenes through the action of single enzyme. In this article, we describe the expression, purification, and chemical assays of NapH4, a difficult to express characterized VHPO that catalyzes the chloronium-induced cyclization of its meroterpenoid substrate.

Exploring the Antitumor Efficacy of N-Heterocyclic Nitrilotriacetate Oxidovanadium(IV) Salts on Prostate and Breast Cancer Cells.

The crystal structures of two newly synthesized nitrilotriacetate oxidovanadium(IV) salts, namely [QH][VO(nta)(H2O)](H2O)2 (I) and [(acr)H][VO(nta)(H2O)](H2O)2 (II), were determined. Additionally, the cytotoxic effects of four N-heterocyclic nitrilotriacetate oxidovanadium(IV) salts-1,10-phenanthrolinium, [(phen)H][VO(nta)(H2O)](H2O)0.5 (III), 2,2'-bipyridinium [(bpy)H][VO(nta)(H2O)](H2O) (IV), and two newly synthesized compounds (I) and (II)-were evaluated against prostate cancer (PC3) and breast cancer (MCF-7) cells. All the compounds exhibited strong cytotoxic effects on cancer cells and normal cells (HaCaT human keratinocytes). The structure-activity relationship analysis revealed that the number and arrangement of conjugated aromatic rings in the counterion had an impact on the antitumor effect. The compound (III), the 1,10-phenanthrolinium analogue, exhibited the greatest activity, whereas the acridinium salt (II), with a different arrangement of three conjugated aromatic rings, showed the lowest toxicity. The increased concentrations of the compounds resulted in alterations to the cell cycle distribution with different effects in MCF-7 and PC3 cells. In MCF-7 cells, compounds I and II were observed to block the G2/M phase, while compounds III and IV were found to arrest the cell cycle in the G0/G1 phase. In PC3 cells, all compounds increased the rates of cells in the G0/G1 phase.

Life cycle GHG emissions assessment of vanadium recovery from bitumen-derived petcoke fly ash.

Petcoke generated during bitumen upgrading is a potential source of vanadium for the global market. Recovering vanadium from the fly ash originating from the combustion of petcoke appears to be a suitable route for commercial implementation, given its high extraction rate. Although the technical feasibility of the recovery process has been proven, the environmental impact should be addressed. Information on the greenhouse (GHG) emissions from the process is scarce in the public domain. Therefore, a framework was developed for assessment of life cycle GHG emissions for extraction of vanadium from petcoke-based fly ash. This framework was used to perform a life cycle GHG emissions assessment of a water leaching and salt roasting process to extract vanadium from fly ash. For the upstream GHG emissions, we collected direct emissions data and energy consumption from the literature, and, for the process emissions, we developed a model to estimate energy and material balances based on process conditions. The emission factors for electricity production, fuel combustion, production of consumables, and gas treatment were used to obtain the life cycle GHG emissions. The results show that the life cycle GHG emission of vanadium recovery are 26.6-3.9+0.9 kg CO2eq/kg V2O5; 66% of these are direct GHG emissions. The process GHG emissions from fly ash decarbonization contribute the most to the life cycle GHG emissions. The air-to-fuel ratio for roasting and the GHG emission factors for petcoke combustion and the gas treatment operation are the inputs that most effect the model output. Compared with the production of V2O5 from vanadium titano-magnetite ore and bitumen upgrading spent catalyst, the petcoke fly ash pathway generates about twice the life cycle GHG emissions. This study's results can help determine areas of improvement in the upstream operations and the recovery process to reduce the life cycle GHG emissions to levels that can compete with primary and alternative routes to produce vanadium pentoxide. The results of this study can help in decision-making associated with vanadium extract from fly ash produced from combustion of petcoke.

Regioselective Halogenation of Lavanducyanin by a Site-Selective Vanadium-Dependent Chloroperoxidase.

Halogenated phenazine meroterpenoids are a structurally unusual family of marine actinobacterial natural products that exhibit antibiotic, antibiofilm, and cytotoxic bioactivities. Despite a lack of established phenazine halogenation biochemistry, genomic analysis of Streptomyces sp. CNZ-289, a prolific lavanducyanin and C2-halogenated derivative producer, suggested the involvement of vanadium-dependent haloperoxidases. We subsequently discovered lavanducyanin halogenase (LvcH), characterized it in vitro as a regioselective vanadium-dependent chloroperoxidase, and applied it in late-stage chemoenzymatic synthesis.

Photocatalytic removal of some selected antibiotics in polluted water system by graphitic carbon nitride-enhanced vanadium ferrite (VFe2O4@g-C3N4).

Antibiotics such as sulfamethoxazole (SUF), ciprofloxacin (CIP) and erythromycin (ERY) are frequently detected in water systems without being efficiently removed during water treatment. This study synthesized a graphitic carbon nitride-enhanced vanadium ferrite (VFe2O4@g-C3N4) as a photocatalyst for degrading SUF, CIP and ERY in an aqueous solution. VFe2O4@g-C3N4 was characterized with X-ray diffractometry (XRD), thermogravimetry analysis (TGA), ultraviolet (UV)-visible spectrophotometry, scanning electron microscope (SEM) and transmission electron microscope (TEM). The XRD characterization of VFe2O4@g-C3N4 revealed diffraction patterns with a crystallite size of 22.45 nm and a bandgap energy of 1.94 eV. The SEM image revealed the surface to be rough with irregular particle shape and size. The TEM image showed an average particle size of 92.47 nm. VFe2O4@g-C3N4 exhibited a degradation efficiency, which showed complete removal of SUF (100 %) from solution while the efficiency towards CIP is 94 ± 0.60 % and 90 ± 0.8 % towards ERY. The best photocatalytic performance was achieved with 0.12 g L-1 of VFe2O4@g-C3N4 and pH = 7.0 as the optimal conditions for achieving complete removal of SUF, CIP and ERY at a concentration lower than 10.00 mg L-1 under visible-light irradiation. The photodegradation of SUF, CIP and ERY by VFe2O4@g-C3N4 was found to be promoted by ROS with ˙OH and SO4˙- radicals playing a significant role. VFe2O4@g-C3N4 demonstrated a regeneration capacity that is above 90 % at the 10th cycle of regeneration treatment, suggesting it to be stable and reusable with the X-ray diffraction pattern remaining unchanged and no leaching of VFe2O4@g-C3N4 into solution. The result from the study reveals VFe2O4@g-C3N4 as a promising photocatalyst for removing antibiotics from an aqueous solution.

Vanadium toxicity was alleviated by supplementation of silicon in tomato seedlings: Upregulating antioxidative enzymes and glyoxalase system.

The primary goal of this research is to investigate the mitigating effect of silicon (Si; 2 mM) on the growth of tomato seedlings under vanadium (V; 40 mg) stress. V stress caused higher V uptake in leaf, and enhanced concentration of leaf anthocyanin, H2O2, O2•-, and MDA, but a decreased in plant biomass, root architecture system, leaf pigments content, mineral elements, and Fv/Fm (PSII maximum efficiency). Si application increased the concentrations of crucial antioxidant molecules such as AsA and GSH, as well as the action of key antioxidant enzymes comprising APX, GR, DHAR, and MDHAR. Importantly, oxidative damage was remarkably alleviated by upregulation of these antioxidant enzymes genes. Moreover, Si application enhanced the accumulation of secondary metabolites as well as the expression their related-genes, and these secondary metabolites may restricted the excessive accumulation of H2O2. In addition, Si rescued tomato plants against the damaging effects of MG by boosting the Gly enzymes activity. The results confirmed that spraying Si to plants might diminish the V accessibility to plants, along with promotion of V stress resistance.

Hydrazone-flavonol based oxidovanadium(V) complexes: Synthesis, characterization and antihyperglycemic activity of chloro derivative in vivo.

Wet synthesis approach afforded four new heteroleptic mononuclear neutral diamagnetic oxidovanadium(V) complexes, comprising salicylaldehyde-based 2-furoic acid hydrazones and a flavonol coligand of the general composition [VO(fla)(L-ONO)]. The complexes were comprehensively characterized, including chemical analysis, conductometry, infrared, electronic, and mass spectroscopy, as well as 1D 1H and proton-decoupled 13C(1H) NMR spectroscopy, alongside extensive 2D 1H1H COSY, 1H13C HMQC, and 1H13C HMBC NMR analyses. Additionally, the quantum chemical properties of the complexes were studied using Gaussian at the B3LYP, HF, and M062X levels on the 6-31++g(d,p) basis sets. The interaction of these hydrolytically inert vanadium complexes and the BSA was investigated through spectrofluorimetric titration, synchronous fluorimetry, and FRET analysis in a temperature-dependent manner, providing valuable thermodynamic insights into van der Waals interactions and hydrogen bonding. Molecular docking was conducted to gain further understanding of the specific binding sites of the complexes to BSA. Complex 2, featuring a 5-chloro-substituted salicylaldehyde component of the hydrazone, was extensively examined for its biological activity in vivo. The effects of complex administration on biochemical and hematological parameters were evaluated in both healthy and diabetic Wistar rats, revealing antihyperglycemic activity at millimolar concentration. Furthermore, histopathological analysis and bioaccumulation studies of the complex in the brain, kidneys, and livers of healthy and diabetic rats revealed the potential for further development of vanadium(V) hydrazone complexes as antidiabetic and insulin-mimetic agents.

Manganese and Vanadium Co-Exposure Induces Severe Neurotoxicity in the Olfactory System: Relevance to Metal-Induced Parkinsonism.

Chronic environmental exposure to toxic heavy metals, which often occurs as a mixture through occupational and industrial sources, has been implicated in various neurological disorders, including Parkinsonism. Vanadium pentoxide (V2O5) typically presents along with manganese (Mn), especially in welding rods and high-capacity batteries, including electric vehicle batteries; however, the neurotoxic effects of vanadium (V) and Mn co-exposure are largely unknown. In this study, we investigated the neurotoxic impact of MnCl2, V2O5, and MnCl2-V2O5 co-exposure in an animal model. C57BL/6 mice were intranasally administered either de-ionized water (vehicle), MnCl2 (252 µg) alone, V2O5 (182 µg) alone, or a mixture of MnCl2 (252 µg) and V2O5 (182 µg) three times a week for up to one month. Following exposure, we performed behavioral, neurochemical, and histological studies. Our results revealed dramatic decreases in olfactory bulb (OB) weight and levels of tyrosine hydroxylase, dopamine, and 3,4-dihydroxyphenylacetic acid in the treatment groups compared to the control group, with the Mn/V co-treatment group producing the most significant changes. Interestingly, increased levels of α-synuclein expression were observed in the substantia nigra (SN) of treated animals. Additionally, treatment groups exhibited locomotor deficits and olfactory dysfunction, with the co-treatment group producing the most severe deficits. The treatment groups exhibited increased levels of the oxidative stress marker 4-hydroxynonenal in the striatum and SN, as well as the upregulation of the pro-apoptotic protein PKCδ and accumulation of glomerular astroglia in the OB. The co-exposure of animals to Mn/V resulted in higher levels of these metals compared to other treatment groups. Taken together, our results suggest that co-exposure to Mn/V can adversely affect the olfactory and nigral systems. These results highlight the possible role of environmental metal mixtures in the etiology of Parkinsonism.

Vanadium and strontium co-doped hydroxyapatite enriched polycaprolactone matrices for effective bone tissue engineering: A synergistic approach.

Scientific research targeted at enhancing scaffold qualities has increased significantly during the last few decades. This emphasis frequently centres on adding different functions to scaffolds in order to increase their usefulness as instruments in the field of regenerative medicine. This study aims to investigate the efficacy of a multifunctional sustainable polymer scaffold, specifically Polycaprolactone (PCL) embedded with hydroxyapatite co-doped with vanadium and strontium (HVS), for bone tissue engineering applications. Polycaprolactone was used to fabricate the scaffold, while hydroxyapatite co-doped with vanadium and strontium (HVS) served as the nanofiller. A thorough investigation of the physicochemical and biological characteristics of the HVS nanofiller was carried out using cutting-edge techniques including Dynamic Light Scattering (DLS), and X-ray Photoelectron Spectroscopy (XPS) and in vitro cell studies. A cell viability rate of more than 70 % demonstrated that the synthesised nanofiller was cytotoxic, but in an acceptable range. The mechanical, biological, and physicochemical properties of the scaffold were extensively evaluated after the nanofiller was integrated. The water absorption characteristics of scaffold were enhanced by the addition of HVS nanofillers, leading to increased swelling, porosity, and hydrophilicity. These improvements speed up the flow of nutrients and the infiltration of cells into the scaffold. The scaffold has been shown to have important properties that stimulate bone cell activity, including better biodegradability and improved mechanical strength, which increased from 5.30 ± 0.37 to 10.58 ± 0.42 MPa. Further, its considerable antimicrobial qualities, blood-compatible nature, and capacity to promote biomineralization strengthen its appropriateness for usage in biomedical applications. Mainly, enhanced Alkaline phosphatase (ALP) activity, Alizarin Red Staining (ARS) activity, and excellent cell adhesive properties, indicating the outstanding osteogenic potential observed in rat bone marrow-derived stromal cells (rBMSC). These combined attributes highlight the pivotal role of these nanocomposite scaffolds in the field of bone tissue engineering.

Melatonin induced reversibility of vanadium toxicity in muskmelon by regulating antioxidant defense and glyoxalase systems.

Agricultural lands with vanadium (V), pose a significant and widespread threat to crop production worldwide. The study was designed to explore the melatonin (ME) treatment in reducing the V-induced phytotoxicity in muskmelon. The muskmelon seedlings were grown hydroponically and subjected to V (40 mg L-1) stress and exogenously treated with ME (100 µmol L-1) to mitigate the V-induced toxicity. The results showed that V toxicity displayed a remarkably adverse effect on seedling growth and biomass, primarily by impeding root development, the photosynthesis system and the activities of antioxidants. Contrarily, the application of ME mitigated the V-induced growth damage and significantly improved root attributes, photosynthetic efficiency, leaf gas exchange parameters and mineral homeostasis by reducing V accumulation in leaves and roots. Additionally, a significant reduction in the accumulation of reactive oxygen species (ROS), malondialdehyde (MDA) along with a decrease in electrolyte leakage was observed in muskmelon seedlings treated with ME under V-stress. This reduction was attributed to the enhancement in the activities of antioxidants in leaves/roots such as ascorbate (AsA), superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), glutathione peroxidase (GPX), glutathione S-transferase (GST) as compared to the V stressed plants. Moreover, ME also upregulated the chlorophyll biosynthesis and antioxidants genes expression in muskmelon. Given these findings, ME treatment exhibited a significant improvement in growth attributes, photosynthesis efficiency and the activities of antioxidants (enzymatic and non-enzymatic) by regulating their expression of genes against V-stress with considerable reduction in oxidative damage.

Impact of Vanadium-Titanium-Magnetite Mining Activities on Endophytic Bacterial Communities and Functions in the Root Systems of Local Plants.

This study utilized 16S rRNA high-throughput sequencing technology to analyze the community structure and function of endophytic bacteria within the roots of three plant species in the vanadium-titanium-magnetite (VTM) mining area. The findings indicated that mining activities of VTM led to a notable decrease in both the biodiversity and abundance of endophytic bacteria within the root systems of Eleusine indica and Carex (p < 0.05). Significant reductions were observed in the populations of Nocardioides, concurrently with substantial increments in the populations of Pseudomonas (p < 0.05), indicating that Pseudomonas has a strong adaptability to this environmental stress. In addition, ß diversity analysis revealed divergence in the endophytic bacterial communities within the roots of E. indica and Carex from the VTM mining area, which had diverged to adapt to the environmental stress caused by mining activity. Functional enrichment analysis revealed that VTM mining led to an increase in polymyxin resistance, nicotinate degradation I, and glucose degradation (oxidative) (p < 0.05). Interestingly, we found that VTM mining did not notably alter the endophytic bacterial communities or functions in the root systems of Dodonaea viscosa, indicating that this plant can adapt well to environmental stress. This study represents the primary investigation into the influence of VTM mining activities on endophytic bacterial communities and the functions of nearby plant roots, providing further insight into the impact of VTM mining activities on the ecological environment.

Oxidovanadium(V) Schiff Base Complexes Derived from Chiral 3-amino-1,2-propanediol Enantiomers: Synthesis, Spectroscopic Studies, Catalytic and Biological Activity.

Oxidovanadium(V) complexes, [(+)VOL1-5] and [(-)VOL1-5], with chiral tetradentate Schiff bases, which are products of monocondensation of S(‒)-3-amino-1,2-propanediol or R(+)-3-amino-1,2-propanediol with salicylaldehyde derivatives, have been synthesized. Different spectroscopic methods, viz. 1H and 51V NMR, IR, UV-Vis, and circular dichroism, as well as elemental analysis, have been used for their detailed characterization. Furthermore, the epoxidation of styrene, cyclohexene, and two monoterpenes, S(‒)-limonene and (‒)-α-pinene, using two oxidants, aqueous 30% H2O2 or tert-butyl hydroperoxide (TBHP) in decane, has been studied with catalytic amounts of all complexes. Finally, biological cytotoxicity studies have also been performed with these oxidovanadium(V) compounds for comparison with cis-dioxidomolybdenum(VI) Schiff base complexes with the same chiral ligands, as well as to determine the cytoprotection against the oxidative damage caused by 30% H2O2 in the HT-22 hippocampal neuronal cells in the range of their 10-100 µM concentration.

Bacterial community drives soil organic carbon transformation in vanadium titanium magnetite tailings through remediation using Pongamia pinnata.

With continuous mine exploitation, regional ecosystems have been damaged, resulting in a decline in the carbon sink capacity of mining areas. There is a global shortage of effective soil ecological restoration techniques for mining areas, especially for vanadium (V) and titanium (Ti) magnetite tailings, and the impact of phytoremediation techniques on the soil carbon cycle remains unclear. Therefore, this study aimed to explore the effects of long-term Pongamia pinnata remediation on soil organic carbon transformation of V-Ti magnetite tailing to reveal the bacterial community driving mechanism. In this study, it was found that four soil active organic carbon components (ROC, POC, DOC, and MBC) and three carbon transformation related enzymes (S-CL, S-SC, and S-PPO) in vanadium titanium magnetite tailings significantly (P < 0.05) increased with P. pinnata remediation. The abundance of carbon transformation functional genes such as carbon degradation, carbon fixation, and methane oxidation were also significantly (P < 0.05) enriched. The network nodes, links, and modularity of the microbial community, carbon components, and carbon transformation genes were enhanced, indicating stronger connections among the soil microbes, carbon components, and carbon transformation functional genes. Structural equation model (SEM) analysis revealed that the bacterial communities indirectly affected the soil organic carbon fraction and enzyme activity to regulate the soil total organic carbon after P. pinnata remediation. The soil active organic carbon fraction and free light fraction carbon also directly regulated the soil carbon and nitrogen ratio by directly affecting the soil total organic carbon content. These results provide a theoretical reference for the use of phytoremediation to drive soil carbon transformation for carbon sequestration enhancement through the remediation of degraded ecosystems in mining areas.

Performance and mechanistic studies of rapid atenolol degradation through peroxymonosulfate activation by V, Co, and bamboo carbon catalyst.

Developing the Co-based catalysts with high reactivity for the sulfate radical (SO4-·)-based advanced oxidation processes (SR-AOPs) has been attracting numerous attentions. To improve the peroxymonosulfate (PMS) activation process, a novel Co-based catalyst simultaneously modified by bamboo carbon (BC) and vanadium (V@CoO-BC) was fabricated through a simple solvothermal method. The atenolol (ATL) degradation experiments in V@CoO-BC/PMS system showed that the obtained V@CoO-BC exhibited much higher performance on PMS activation than pure CoO, and the V@CoO-BC/PMS system could fully degrade ATL within 5 min via the destruction of both radicals (SO4-· and O2-··) and non-radicals (1O2). The quenching experiments and electrochemical tests revealed that the enhancing mechanism of bamboo carbon and V modification involved four aspects: (i) promoting the PMS and Co ion adsorption on the surface of V@CoO-BC; (ii) enhancing the electron transfer efficiency between V@CoO-BC and PMS; (iii) activating PMS with V3+ species; (iv) accelerating the circulation of Co2+ and Co3+, leading to the enhanced yield of reactive oxygen species (ROS). Furthermore, the V@CoO-BC/PMS system also exhibited satisfactory stability under broad pH (3-9) and good efficiency in the presence of co-existing components (HCO3-, NO3-, Cl-, and HA) in water. This study provides new insights to designing high-performance, environment-friendly bimetal catalysts and some basis for the remediation of antibiotic contaminants with SR-AOPs.

EGCG-vanadium nanomedicine with neutral pH Fenton reaction activity inhibits heat shock proteins for enhanced photothermal/chemodynamic therapy.

A burgeoning interest has recently focused on the development of nanomedicine to integrate noninvasive photothermal therapy (PTT) and chemodynamic therapy (CDT) for synergistic tumor treatments, owing to PTT's amplification effect on CDT. However, challenges emerge as hyperthermia often induces an unwarranted overexpression of cytoprotective heat shock proteins (HSPs), thereby curtailing PTT efficacy. Additionally, the nearly neutral tumor intracellular pH (pHi ≈ 7.2) that handicaps the Fenton reaction poses a leading limitation to CDT. Addressing these hurdles, we introduce EVP, a nanomedicine developed through the straightforward assembly of epigallocatechin gallate (EGCG), vanadium sulfate (VOSO4), and Pluronic F-127 (PF127). EVP comprehensively downregulates overexpressed HSPs (HSP 60, 70, 90) through the collaborative action of EGCG and vanadyl (VO2+). Moreover, the tumor intracellular pH-processed Fenton-like reaction by VO2+ ensures highly efficient hydroxyl radicals (OH) production in cytosols, overcoming the stringent acidity requirement for CDT. Additionally, the hyperthermia induced by PTT augments OH production, further enhancing CDT efficacy. In vitro and in vivo experiments validate EVP's excellent biocompatibility and potent tumor inhibition, highlighting its substantial potential in tumor therapy.