The recently recognized adverse environmental and toxic effects of neonicotinoid insecticides (NNIs) on non-target organisms are alarming. A comprehensive design, screening, and regulatory system was developed to generate NNI derivatives and mutant receptors with selective-ecotoxicological effects to overcome such adverse effects. For ligand design, taking ACE-09 derivative as an example, the toxicity on non-target animals (aboveground: bees; underground: earthworms), plant absorption, and soil absorption decreased by 4.80% and 13.7%, 10.0%, and 121%, while the toxicity on target animals (aboveground: aphids; underground: B. odoriphagas), plant metabolism, and soil degradation increased by 70.2% and 51.7%, 5.08%, and 8.28%. For receptor modification, the ability of mutants to absorb ACE-09 derivative decreased by 31.0%, while the ability of mutants to metabolize ACE-09 derivative increased by 28.0% in scenario 2 (mainly plant selectivity); the ability of mutants to degrade ACE-09 derivative increased by 11.6% in scenario 3 (mainly soil selectivity). The above results indicated that the selective-ecotoxicological effects of ligand design and receptor modification were both improved. Additionally, the combined effects of the ACE-09 derivative on plant absorption and metabolic mutants improved by 31.1% and 31.4% in scenario 2, respectively, while the effect on microbial degradation mutant improved by 14.9%, indicating that there was a synergistic effect between ligand design and receptor modification. Finally, based on the interaction between the ACE-09 derivative and mutants, the optimal environmental factors that improved the selectivity of their ecotoxicological effects were determined. For example, alternate application of nitrogen and phosphorus fertilizers effectively reduced the oxidative damage to plants caused by NNI residues. The novel ligand-receptor joint modification method, combined with the regulation of environmental factors under multiple scenarios, can biochemically address the ecotoxicological concern and highlight the harmful effects of pesticides on the environment and non-target organisms.

Bacteria and their secreted extracellular polymeric substances (EPS) are widely distributed in ecosystems and have high capacity for heavy metal immobilization. The knowledge about the molecular-level interactions with heavy metal ions is essential for predicting the behavior of heavy metals in natural and engineering systems. This comprehensive study using potentiometric titration, Fourier-transform infrared (FTIR) spectroscopy, isothermal titration calorimetry (ITC) and X-ray absorption fine structure (XAFS) was able to reveal the functional diversity and adsorption mechanisms for Pb onto bacteira and the EPS in greater detail than ever before. We identified mono-carboxylic, multi-carboxylic, phosphodiester, phosphonic and sulfhydryl sites and found the partitioning of Pb to these functional groups varied between gram-negative and gram-positive bacterial strains, the soluble and cell-bound EPS and Pb concentrations. The sulfhydryl and phosphodiester groups preferentially complexed with Pb in P. putida cells, while multifunctional carboxylic groups promoted Pb adsorption in B. subtilis cells and the protein fractions in EPS. Though the functional site diversity, the adsorption of Pb to organic ligands occurred spontaneously through a universal entropy increase and inner-sphere complexation mechanism. The functional group scale knowledge have implications for the modeling of heavy metal behavior in the environment and application of these biological resources.

Exposure to environmental endocrine disrupting chemicals (EDCs) is highly suspected in prostate carcinogenesis. Though, estrogenicity is the most studied behavior of EDCs, the androgenic potential of most of the EDCs remains elusive. This study investigates the androgen mimicking potential of some common EDCs and their effect in androgen-dependent prostate cancer (LNCaP) cells. Based on the In silico interaction study, all the 8 EDCs tested were found to interact with androgen receptor with different binding energies. Further, the luciferase reporter activity confirmed the androgen mimicking potential of 4 EDCs namely benzo[a]pyrene, dichlorvos, genistein and β-endosulfan. Whereas, aldrin, malathion, tebuconazole and DDT were reported as antiandrogenic in luciferase reporter activity assay. Next, the nanomolar concentration of androgen mimicking EDCs (benzo[a]pyrene, dichlorvos, genistein and β-endosulfan) significantly enhanced the expression of AR protein and subsequent nuclear translocation in LNCaP cells. Our In silico studies further demonstrated that androgenic EDCs also bind with epigenetic regulatory enzymes namely DNMT1 and HDAC1. Moreover, exposure to these EDCs enhanced the protein expression of DNMT1 and HDAC1 in LNCaP cells. These observations suggest that EDCs may regulate proliferation in androgen sensitive LNCaP cells by acting as androgen mimicking ligands for AR signaling as well as by regulating epigenetic machinery. Both androgenic potential and epigenetic modulatory effects of EDCs may underlie the development and growth of prostate cancer.

Because the pollutants produced by human activities have destroyed the ecological balance of natural water environment, and caused severe impact on human life safety and environmental security. Hence the task of water environment restoration is imminent. Metal-organic frameworks (MOFs), structured from organic ligands and inorganic metal ions, are notable for their outstanding crystallinity, diverse structures, large surface areas, adsorption performance, and excellent component tunability. The water stability of MOFs is a key requisite for their possible actual applications in separation, catalysis, adsorption, and other water environment remediation areas because it is necessary to safeguard the integrity of the material structure during utilization. In this article, we comprehensively review state-of-the-art research progress on the promising potential of MOFs as excellent nanomaterials to remove contaminants from the water environment. Firstly, the fundamental characteristics and preparation methods of several typical water-stable MOFs include UiO, MIL, and ZIF are introduced. Then, the removal property and mechanism of heavy metal ions, radionuclide contaminants, drugs, and organic dyes by different MOFs were compared. Finally, the application prospect of MOFs in pollutant remediation prospected. In this review, the synthesis methods and application in water pollutant removal are explored, which provide ways toward the effective use of water-stable MOFs in materials design and environmental remediation.

It has not been well understood that the binding affinity and potential toxicity of different chemical forms of selenite (Se(IV)), which are predominant forms of selenium with plant availability. The influences of pH and major anions on Se(IV) toxicity to wheat root elongation were determined in solutions and modeled based on the biotic ligand model (BLM) and free ion activity model (FIAM) concepts. Results showed that EC50[Se(IV)]T values increased from 164 to 273 μM as the pH raised from 4.5 to 8.0, indicating the increase of pH induced weakened Se(IV) toxicity. The EC50{SeO₃²⁻} values increased from 0.019 to 71.3 μM while the EC50{H₂SeO₃} values sharply decreased from 2.08 μM to 0.760 nM with the pH increasing from 4.5 to 8.0. The effect of pH on Se(IV) toxicity could be explained by the changes of Se(IV) species in different pH solutions as H₂SeO₃, HSeO₃⁻ and SeO₃²⁻ were differently toxic to wheat root elongation. The toxicity of Se(IV) decreased with increasing H₂PO₄⁻ activity but not for SO₄²⁻, NO₃⁻ and Cl⁻ activities, indicating that only H₂PO₄⁻ had a competitive effect with Se(IV) on the binding sites. A site-specific BLM was developed to count in effects of pH and H₂PO₄⁻, and stability constants of H₂SeO₃, HSeO₃⁻, SeO₃²⁻ and H₂PO₄⁻ to the binding sites were obtained: logKH2SeO3BL = 4.96, logKHSeO3BL = 3.47, logKSeO3BL = 2.56 and logKH2PO4BL = 2.00. Results implied that BLM performed much better than FIAM in the wheat root elongation prediction when coupling toxic species H₂SeO₃, HSeO₃⁻, SeO₃²⁻, and the competitions of H₂PO₄⁻ for the binding sites while developing the Se(IV)-BLM.

Imidacloprid (IMI) is widely used in agriculture, and is toxic to non-target aquatic species. Quercetin (Que) is a flavonoid abundant in fruits and vegetables that exhibits anti-oxidant activity. In the present study, we treated grass carp hepatocytes (L8824) with 0.1 μM Que and/or 1 mM IMI for 24 h to explore the effect of Que on IMI-induced mitochondrial apoptosis. We found that IMI exposure enhanced reactive oxygen species (ROS) generation, inhibiting the activities of SOD, CAT and T-AOC, exacerbating the accumulation of MDA, aggravating the expression of mitochondrial apoptosis pathway (Cyt-C, BAX, Caspase9 and Caspase3) related genes and decreased the expression of anti-apoptosis gene B-cell lymphoma-2 (Bcl-2). In addition, Que and IMI co-treatment significantly restored the activity of anti-oxidant enzymes, downregulated ROS level and apoptosis rate, thereby alleviating the depletion of mitochondrial membrane potential (ΔΨm) and the expression of cytochrome c (Cyt-C), Bcl-2-associated X (BAX), and cysteinyl aspartate specific proteinases (Caspase9 and 3), increasing the Bcl-2 level. Furthermore, we elucidated that Que could inhibit the expression of phosphatase and tensin homolog deleted on chromosome 10 (PTEN), thus activating phosphatidylinositol 3-kinase/protein kinase B (PI3K/AKT) pathway to attenuate IMI-induced apoptosis. Molecular docking provides assertive evidence for the interaction between Que ligand and PTEN receptor. Consequently, these results indicate that Que effectively antagonizes IMI-induced mitochondrial apoptosis in grass carp hepatocytes via regulating the PTEN/PI3K/AKT pathway.

Dioxybenzone is widely used in cosmetics and personal care products and frequently detected in multiple environmental media and human samples. However, the current understanding of the metabolic susceptibility of dioxybenzone and the potential endocrine disruption through its metabolites in mimicking human estrogens remains largely unclear. Here we investigated the in vitro metabolism of dioxybenzone, detected the residue of metabolites in rats, and determined the estrogenic disrupting effects of these metabolites toward estrogen receptor α (ERα). In vitro metabolism revealed two major metabolites from dioxybenzone, i.e., M1 through the demethylation of methoxy moiety and M2 through hydroxylation of aromatic carbon. M1 and M2 were both rapidly detected in rat plasma upon exposure to dioxybenzone, which were then distributed into organs of rats in the order of livers > kidneys > uteri > ovaries. The 100 ns molecular dynamics simulation revealed that M1 and M2 formed hydrogen bond to residue Leu387 and Glu353, respectively, on ERα ligand binding domain, leading to a reduced binding free energy. M1 and M2 also significantly induced estrogenic effect in comparison to dioxybenzone as validated by the recombinant ERα yeast two-hybrid assay and uterotrophic assay. Overall, our study revealed the potential of metabolic activation of dioxybenzone to induce estrogenic disrupting effects, suggesting the need for incorporating metabolic evaluation into the health risk assessment of benzophenones and their structurally similar analogs.

In this study, the YH consortium, an ethene-producing culture, was used to evaluate the effect of vitamin B₁₂ (VB₁₂) on trichloroethene (TCE) dechlorination by transferring the original TCE-reducing culture with or without adding exogenous VB₁₂. Ultra-high performance liquid chromatography - tandem mass spectrometry (UPLC-MS/MS) was applied to detect the concentrations of VB₁₂ and its lower ligand 5,6-dimethylbenzimidazole (DMB) in the cultures. After three successive VB₁₂ starvation cycles, the dechlorination of TCE stopped mostly at cis-dichloroethene (cDCE), and no ethene was found; methane production increased significantly, and no VB₁₂ was detected. Results suggest that the co-cultured microbes may not be able to provide enough VB₁₂ as a cofactor for the growth of Dehalococcoides in the YH culture, possibly due to the competition for corrinoids between Dehalococcoides and methanogens. The relative abundances of 16 S rRNA gene of Dehalococcoides and reductive dehalogenase genes tceA or vcrA were lower in the cultures without VB₁₂ compared with the cultures with VB₁₂. VB₁₂ limitation changed the microbial community structures of the consortia. In the absence of VB₁₂, the microbial community shifted from dominance of Chloroflexi to Proteobacteria after three consecutive VB₁₂ starvation cycles, and the dechlorinating genus Dehalococcoides declined from 42.9% to 13.5%. In addition, Geobacter, Clostridium, and Desulfovibrio were also present in the cultures without VB₁₂. Furthermore, the abundance of archaea increased under VB₁₂ limited conditions. Methanobacterium and Methanosarcina were the predominant archaea in the culture without VB₁₂.

Achieving large pore size, high catalytic performance with stable structure is critical for metal–organic frameworks (MOFs) to have more hopeful prospects in catalytic applications. Herein, we had reported a method to synthesize highly reactive yet stable defective iron-based Metal organic frameworks by using different monocarboxylic acids with varying lengths as a modulator. The physical−chemical characterization illustrating that modulators could improve the crystallinity, enlarge pore size and enhance catalytic performance and octanoic acid (OA) was screened to be the suitable choice. The catalytic performance of catalysts was detected through persulfate (PS) activation for degrading Tetrabromobisphenol A (TBBPA). The study demonstrated that the highest degradation efficiency for 0.018 mmol L−1 TBBPA was that 97.79% in the conditions of the 1.0 g L−1 Fe(BDC)(DMF,F)-OA-30 dosage and TBBPA:PS = 200:1. In addition, there was observed that no obvious change of the crystal structure, little the leachable iron concentration in the solutions and no significant loss of catalytic activities of Fe(BDC)(DMF,F)-OA-30 after 5th cycles. The iron valence state of Fe(BDC)(DMF,F)-OA-30 before and after degradation and electrochemical properties reveal that the partial substitution of organic ligands by octanoic acid, when removing OA and forming defects by heat and vacuum treatment to generate coordinatively unsaturated metal sites and accelerate the original transmission of electronic, leading to enhance the activity of persulfate activation for efficient removal TBBPA.

Understanding how essential and toxic elements are distributed in cereal grains is a key to improving the nutritional quality of cereal-based products. The main objective of this work was to characterize the distribution of Cd and of nutrients (notably Cu, Fe, Mn, P, S and Zn) in the durum wheat grain. Laser ablation inductively coupled mass spectrometry and synchrotron micro X-ray fluorescence were used for micro-scale mapping of Cd and nutrients. A dissection approach was used to quantitatively assess the distribution of Cd and nutrients among grain tissues. Micro X-ray absorption near-edge spectroscopy was used to identify the Cd chemical environment in the crease. Cadmium distribution was characterized by strong accumulation in the crease and by non-negligible dissemination in the endosperm. Inside the crease, Cd accumulated most in the pigment strand where it was mainly associated with sulfur ligands. High-resolution maps highlighted very specific accumulation areas of some nutrients in the germ, for instance Mo in the root cortex primordia and Cu in the scutellum. Cadmium loading into the grain appears to be highly restricted. In the grain, Cd co-localized with several nutrients, notably Mn and Zn, which challenges the idea of selectively removing Cd-enriched fractions by dedicated milling process.