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Sulfate-reducing bacteria (SRB) are known to alter methylmercury (MeHg) production in paddy soil, but the effect of SRB on MeHg dynamics in rhizosphere and rice plants remains to be fully elucidated. The present study investigated the impact of SRB on MeHg levels in unsterilized and γ-sterilized mercury-polluted paddy soils, with the aim to close this knowledge gap. Results showed that the presence of SRB reduced MeHg production by ∼22 % and ∼17 % in the two soils, but elevated MeHg contents by approximately 55 % and 99 % in rice grains, respectively. Similar trend at smaller scales were seen in roots and shoots. SRB inoculation exerted the most profound impact on amino acid metabolism in roots, with the relative response of L-arginine positively linking to MeHg concentrations in rhizosphere. The SRB-induced enrichment of MeHg in rice plants may be interpreted by the stronger presence of endophytic nitrogen-related microbes (e.g. Methylocaldum , Hyphomicrobium and Methylocystis) and TGA transcription factors interacting with glutathione metabolism and calmodulin. Our study provides valuable insights into the complex effects of SRB inoculation on MeHg dynamics in rice ecosystems, and may help to develop strategies to effectively control MeHg accumulation in rice grains. [Display omitted] • SRB inoculation mitigated MeHg production in rhizosphere soil. • SRB inoculation facilitated MeHg enrichment in rice. • Endophytic nitrogen-related microbes could promote MeHg accumulation in rice. • TGA transcription factor could boost MeHg accumulation in rice. • L-arginine can be deemed as the indicator for soil MeHg concentrations. [ABSTRACT FROM AUTHOR]

Biochar could reshape microbial communities, thereby altering methylmercury (MeHg) concentrations in rice rhizosphere and seeds. However, it remains unclear whether and how biochar amendment perturbs microbe-mediated MeHg production in mercury (Hg) contaminated paddy soil. Here, we used pinecone-derived biochar and its six modified biochars to reveal the disturbance. Results showed that selenium- and chitosan-modified biochar significantly reduced MeHg concentrations in the rhizosphere by 85.83% and 63.90%, thereby decreasing MeHg contents in seeds by 86.37% and 75.50%. The two modified bicohars increased the abundance of putative Hg-resistant microorganisms Bacillus , the dominant microbe in rhizosphere. These reductions about MeHg could be facilitated by biochar sensitive microbes such as Oxalobacteraceae and Subgroup_7. Pinecone-derived biochar increased MeHg concentration in rhizosphere but unimpacted MeHg content in seeds was observed. This biochar decreased the abundance in Bacillus but enhanced in putative Hg methylator Desulfovibrio. The increasing MeHg concentration in rhizosphere could be improved by biochar sensitive microbes such as Saccharimonadales and Clostridia. Network analysis showed that Saccharimonadales and Clostridia were the most prominent keystone taxa in rhizosphere, and the three biochars manipulated abundances of the microbes related to MeHg production in rhizosphere by those biochar sensitive microbes. Therefore, selenium- and chitosan-modified biochar could reduce soil MeHg production by these microorganisms, and is helpful in controlling MeHg contamination in rice. [Display omitted] • Effects of six modified biochars on the enrichment of MeHg in rice were compared • Selenium and chitosan modified biochars greatly reduced MeHg contents in rice. • Bacillus altered soil MeHg production by MeHg degradation under biochar amendment. • Saccharimonadales and Clostridia could increase MeHg contents in rhizosphere. [ABSTRACT FROM AUTHOR]

Abstract Several strains of archaea have the ability to methylate or resist mercury (Hg), and the paddy field is regarded to be conducive to Hg methylation. However, our knowledge of Hg-methylating or Hg-resistant archaea in paddy soils is very limited so far. Therefore, the distribution of archaea and bacteria in the rhizosphere (RS) and bulk soil (BS) of the rice growing in Xiushan Hg-mining area of southwest China was investigated. Bacterial and archaeal 16S rRNA gene amplicon sequencing of the rice rhizosphere along the Hg gradient was conducted. THg concentrations in RS were significantly higher than that in BS at site S1 and S2, while MeHg concentrations in RS was always higher than that in BS, except S6. Bacterial species richness estimates were much higher than that in archaea. The bacterial α-diversity in high-Hg sites was significant higher than that in low-Hg sites based on ACE and Shannon indices. At the genus level, Thiobacillus , Xanthomonas , Defluviicoccus and Candidatus Nitrosoarchaeum were significantly more abundant in the rhizosphere of high-Hg sites, which meant that strains in these genera might play important roles in response to Hg stress. Hg-methylating archaea in the paddy field could potentially be affiliated to strains in Methanosarcina , but further evidence need to be found. The results provide reference to understand archaeal rhizosphere community along an Hg gradient paddy soils. Graphical abstract Unlabelled Image Highlights • Communities of bacteria and archaea in Hg-polluted rice rhizosphere were studied firstly. • Bacteria between high and low-Hg sites clustered together respectively, so did archaea. • merA abundance was significant higher in high-Hg sites than low-Hg sites. • Methanogen Hg-methylators could potentially be affiliated to Methanosarcina. [ABSTRACT FROM AUTHOR]

Background Thymoquinone (TQ), the major active compound isolated from black seed oil ( Nigella sativa ), has been reported to exhibit anti-inflammatory and anticancer abilities. However, the exact molecular mechanism underlying the anticancer effect of TQ is still poorly understood, especially in regard to TQ's effect on endoplasmic reticulum stress-mediated apoptosis. Methods The cytotoxicity of TQ on T24 and 253J bladder cancer cells was analyzed by MTT assay, colony formation assay and Annexin V-FITC/PI staining, while SV-HUC-1, the SV-40 immortalized human uroepithelial cell line, was used as a normal control. The change in mitochondrial membrane potential was assessed by JC-1 staining. mRNA expression and protein expression were detected by qPCR and western blotting. Caspase-3 activity was detected by colorimetric assay. Key finding TQ has a significant cytotoxicity on bladder cancer cells and can inhibit their proliferation and induce apoptosis. The protein changes of Bcl-2, Bax, cytochrome c and endoplasmic reticulum stress-related proteins (GRP78, CHOP, and caspase-12) revealed that the anticancer effect of TQ was associated with mitochondrial dysfunction and the endoplasmic reticulum stress pathway. Pretreatment with a pan-caspase inhibitor, Z-VAD-fmk, or an ER stress inhibitor, 4-PBA, or knockdown of CHOP by shRNA can partly reverse the pro-apoptotic effect of TQ by enhancing the expression of the anti-apoptotic protein Bcl-2, blocking the release of cytochrome c and the translocation of Bax from the cytoplasm to mitochondria. Significance Our findings provide the first demonstration of the anticancer effect of TQ on bladder cancer, and the relationship between ER stress and mitochondrial dysfunction was clearly understood when the apoptosis progressed is revealed. [ABSTRACT FROM AUTHOR]

Forests play a significant role in the biogeochemical cycling of mercury (Hg). Litterfall represent a dominant pathway for Hg to reach the ground surface under a forest canopy. In order to understand Hg accumulation in the litterfall, the dynamics of Hg, carbon (C), nitrogen (N), microbial C and N, as well as bacterial community in the decaying litterfall of two typical subtropical forest stands in southwest China were investigated for one year. THg levels in the litterfall after one-year increased to 124.64% and 135.90%, and MeHg levels in the litterfall increased up to 295.65% and 209.38% of the initial values in the mixed broadleaf-conifer forest and evergreen broadleaf forest respectively. Differently, the concentrations of THg and MeHg in the organic layer of the underlying soil were quite stable. The concentrations of THg in the decaying litterfall corresponded negatively with C/N ratios. Bacterial community analysis found that the bacteria previously being confirmed as Hg methylators did not occur in the genera of the decomposing litterfall in the two forest stands, which might imply that the increase of MeHg during decomposing did not mainly due to the contribution of confirmed Hg methylators, and other sources of MeHg might exert certain roles. [ABSTRACT FROM AUTHOR]

Over 3000 mercury (Hg)-contaminated sites worldwide contain liquid metallic Hg [Hg(0) l ] representing a continuous source of elemental Hg(0) in the environment through volatilization and solubilization in water. Currently, there are few effective treatment technologies available to remove or sequester Hg(0) l in situ. We investigated sonochemical treatments coupled with complexing agents, polysulfide and sulfide, in oxidizing Hg(0) l and stabilizing Hg in water, soil and quartz sand. Results indicate that sonication is highly effective in breaking up and oxidizing liquid Hg(0) l beads via acoustic cavitation, particularly in the presence of polysulfide. Without complexing agents, sonication caused only minor oxidation of Hg(0) l but increased headspace gaseous Hg(0) g and dissolved Hg(0) aq in water. However, the presence of polysulfide essentially stopped Hg(0) volatilization and solubilization. As a charged polymer, polysulfide was more effective than sulfide in oxidizing Hg(0) l and subsequently stabilizing the precipitated metacinnabar (β-HgS) nanocrystals. Sonochemical treatments with sulfide yielded incomplete oxidation of Hg(0) l , likely resulting from the formation of HgS coatings on the dispersed µm-size Hg(0) l bead surfaces. Sonication with polysulfide also resulted in rapid oxidation of Hg(0) l and precipitation of HgS in quartz sand and in the Hg(0) l -contaminated soil. This research indicates that sonochemical treatment with polysulfide could be an effective means in rapidly converting Hg(0) l to insoluble HgS precipitates in water and sediments, thereby preventing its further emission and release to the environment. We suggest that future studies are performed to confirm its technical feasibility and treatment efficacy for remediation applications. [Display omitted] • Sonochemical oxidation and stabilization of liquid elemental mercury [Hg(0) l ] are evaluated in water and soil. • Sonication promotes the breakup and oxidation of Hg(0) l beads via acoustic cavitation. • Sonication coupled with polysulfide prevents Hg(0) l solubilization and volatilization loss. • Polysulfide is more effective than sulfide in sonochemical oxidation of Hg(0) l and formation of HgS nanocrystals. • Sonochemical treatment offers a potentially effective means for rapidly converting Hg(0) l to HgS in water and soil. [ABSTRACT FROM AUTHOR]

Anaerobic activated sludge is rich in humic substances and water, leading to significant differences in the stability of metagenomic DNA and metatranscriptomic RNA. Thus, it is of great difficulty to exact high-quality and high-yield DNA and RNA from them, especially those cultured at a wide range of temperatures. Here, we established fast and effective DNA and RNA extraction methods based on current commercial kits. The modified methods combined liquid nitrogen grinding with kits, achieving notable improvements in concentrations, yields, purity and integrities for both DNA and RNA. The ratios of OD260/280 of the metagenomic DNA were between 1.81 ± 0.03 and 1.83 ± 0.02, while OD260/280 and OD260/230 of the metatranscriptomic RNA ranged from 1.96 ± 0.01 to 2.13 ± 0.03 and from 1.94 ± 0.02 to 2.30 ± 0.03 respectively. Metagenomic DNA and metatranscriptomic RNA obtained by the modified methods perfectly met the requirements of second- and third-generation sequencing, providing valuable reference for extracting high-quality metagenomic DNA and metatranscriptomic RNA from environmental samples of high water content and humic substances under temperatures ranging from 18 °C to 52 °C. • Liquid nitrogen grinding combined with kits generated high-quality DNA/RNA. • DNA/RNA extracted improved greatly in concentration, yield, purity and integrity. • The methods are suitable for sludge at a wide range of temperatures. [ABSTRACT FROM AUTHOR]

Abstract: The object of the research was to determine the antioxidant effect of cassia essential oil on deep-fried beef during the frying process. The rules and optimum processing conditions of deep-fried beef with addition of cassia essential oil were discussed through an orthogonal experiment and some single factor experiments (frying time, frying temperature, oil types and concentration of essential oil). The antioxidant effect was evaluated by peroxide and TBA value. Results showed that the antioxidant effect of cassia oil during the frying process was optimum under the conditions of 30μL cassia oil/250mL palm oil, 1.5min at 150°C. The main compositions of cassia oil were analysed by GC–MS method. [Copyright &y& Elsevier]

[Display omitted] • Acetoclastic pathway was most important in low-temperature MES. • Methahnosarcina and Methanothrix were enriched in DC and SC reactor, respectively. • Electroactive bacteria Syntrophomonas , Pseudomonas and Bacteroides were dominated. • The single-chamber MES achieve acetate to acetyl-CoA by acetate-CoA ligase. • The dual-chamber MES was by acetate kinase and phosphate acetyltransferase. In this study, single-chamber and dual-chamber Microbial electrosynthesis (MES) with carbon fiber brushes as electrodes were operated at 15°C to compare and analyze the difference in methanogenic performance. Metatranscriptomic analysis showed that the relative abundance of electroactive microorganisms Syntrophomonas , Pseudomonas and Bacteroides in each group exceeded 90%, while the abundance of Geobacter was less than 4%. Acetoclastic methanogens Methahnosarcina was more enriched in dual-chamber MES (61.74%~70.42%), and Methanothrix showed higher abundance in single-chamber MES (33.44%~51.71%). Methahnosarcina and Methanothrix could interact with electroactive microorganisms to improve the electron transfer efficiency through direct interspecies electron transfer (DIET). Analysis of the methane metabolic pathways of low-temperature MES found acetoclastic pathway was domination, and single-chamber MES achieved acetate to acetyl-CoA through acetate-CoA ligase (EC: 6.2.1.1), whereas dual-chamber MES was by acetate kinase (EC: 2.7.2.1) and phosphate acetyltransferase (EC: 2.3.1.8). These results are beneficial to further research on the treatment of low-temperature wastewater. [ABSTRACT FROM AUTHOR]

Hypertension is a leading risk factor for developing kidney disease. Current single-target antihypertensive drugs are not effective for hypertensive nephropathy, in part due to its less understood mechanism of pathogenesis. We recently showed that QiShenYiQi (QSYQ), a component-based cardiovascular Chinese medicine, is also effective for ischemic stroke. Given the important role of the brain-heart-kidney axis in blood pressure control, we hypothesized that QSYQ may contribute to blood pressure regulation and kidney protection in Dahl salt-sensitive hypertensive rats. The therapeutic effects of QSYQ on blood pressure and kidney injury in Dahl salt-sensitive rats fed with high salt for 9 weeks were evaluated by tail-cuff blood pressure monitoring, renal histopathological examination and biochemical indicators in urine and serum. RNA-seq was conducted to identify QSYQ regulated genes in hypertensive kidney, and RT-qPCR, immunohistochemistry, and Western blotting analysis were performed to verify the transcriptomics results and validate the purposed mechanisms. QSYQ treatment significantly decreased blood pressure in Dahl salt-sensitive hypertensive rats, alleviated renal tissue damage, reduced renal interstitial fibrosis and collagen deposition, and improved renal physiological function. RNA-seq and subsequent bioinformatic analysis showed that the expression of ADRA1D and SIK1 genes were among the most prominently altered by QSYQ in salt-sensitive hypertensive rat kidney. RT-qPCR, immunohistochemistry and Western blotting results confirmed that the mRNA and protein expression levels of alpha-1D adrenergic receptor (ADRA1D) in the kidney tissue of the QSYQ-treated rats were markedly down-regulated, while the mRNA and protein levels of salt inducible kinase 1 (SIK1) were significantly increased. QSYQ not only lowered blood pressure, but also alleviated renal damage via reducing the expression of ADRA1D and increasing the expression of SIK1 in the kidney of Dahl salt-sensitive hypertensive rats. [Display omitted] • A first report that a compont-based Chinese medicine QiShenYiQi is effective against hypertension. • QSYQ not only lowers salt-induced high blood pressure, but also ameliorates the sequential kidney injury. • Coordinated ADRA1D downregulation and SIK1 upregulation as a mechanism of renal protection by QSYQ. [ABSTRACT FROM AUTHOR]

The identification of dominant microbes in anaerobic mercury (Hg) methylation, methylmercury (MeHg) demethylation, and methane oxidation as sulfate-reducing bacteria, methanogens or, probably, anaerobic methanotrophic archaea (ANMEs) is of great interest. To date, however, the interrelationship of bacteria and archaea involved in these processes remains unclear. Here, we demonstrated the dynamics of microorganisms participating in these processes. Anaerobic fixed-bed reactors were operated with swine manure and sludge to produce methane stably, and then, sulfate (reactor C), sulfate and Hg(II) (reactor H), and sulfate and MeHg (reactor M) were added, and the reactors were operated for 120 d, divided equally into four periods, P1–P4. The bacterial compositions changed nonsignificantly, whereas Methanosaeta in reactors H and M decreased significantly, revealing that it was irrelevant for Hg transformation. The abundances of Syntrophomonadaceae , Methanoculleus , Candidatus Methanogranum and Candidatus Methanoplasma increased continuously with time; these species probably functioned in these processes, but further evidence is needed. Desulfocella and Desulfobacterium dominated first but eventually almost vanished, while the dominant archaeal genera Methanogenium , Methanoculleus and Methanocorpusculum were closely related to ANME–1 and ANME–2. PLS-DA results indicated that both bacteria and archaea in different periods in the three reactors were clustered separately, implying that the microbial compositions in the same periods were similar and changed markedly with time. [Display omitted] • Methanosaeta decreased significantly after adding Hg and was unrelated to Hg transformation. • Desulfocella and Desulfobacterium dominated first but finally almost vanished. • The dominant archaeal genera were closely related to ANME–1 and ANME–2. • Microbes in different periods clustered separately, showing a significant change with time. [ABSTRACT FROM AUTHOR]

Methylmercury (MeHg) in rice is presumed to be derived from MeHg formed in the soil, although it is still controversial. Moderate soil mercury (Hg) concentration can affect the diversity of soil microorganisms and may also impact the physiological changes and MeHg absorption of rice. In this study, the pot experiment was conducted to explore the effects of Hg concentration gradients (0, 0.3, 3, and 30 mg kg−1) stress on Hg transformation in the rhizosphere, Hg translocation in rice, and physiological changes in rice leaves during the whole rice growing season. Moderate soil Hg concentration (3 mg kg−1) greatly increased the MeHg/THg (1.69%) of rhizosphere, while 30 mg kg−1 soil Hg concentration sharply reduced the MeHg/THg (0.29%) of rhizosphere. Highest MeHg/THg of the four groups all appeared at the blooming or filling stage. There was a significant positive correlation between Fe2+ in rhizosphere and MeHg/THg, but no significant correlation between SO 4 2− and MeHg/THg was observed. Although the 3 mg kg−1 soil Hg concentration significantly enhanced MeHg concentrations in seeds, it considerably reduced the bioaccumulation factors of MeHg in roots, stalks, old leaves and young leaves. Soil Hg concentration of 30 mg kg−1, to a certain extent, curtailed MeHg concentrations in seeds, while MeHg concentrations in the husk were significantly increased. Consistent with the result that there was no significant difference for THg concentrations in old and young leaves among the four Hg treatment groups, the content of chlorophyll, H 2 O 2 , malondialdehyde and antioxidant substances, and the activities of antioxidant enzyme in old and young leaves varied indistinctly among groups. Moderate soil mercury concentration (3 mg kg−1) could extremely enhance MeHg production in the rhizosphere soil and its accumulation in rice; MeHg production in the rhizosphere soil increased greatly at the blooming or filling stage, whereas little effect on antioxidant systems in leaves was observed. Unlabelled Image • Highest MeHg/THg occurred with soil mercury concentration of 3 mg kg−1. • Highest MeHg/THg appeared at the blooming or filling stage. • MeHg concentrations in seeds reduced to some extent under Hg stress of 30 mg kg−1. • Little effect on the antioxidant system in leaves with mercury gradient was observed. [ABSTRACT FROM AUTHOR]

• Cumulative methane production was not significantly different between the two reactors. • Acidogens and H 2 -producing bacteria were higher in the single-chamber MES. • Fermentation bacteria and methanogens were concentrated in the dual-chamber MES. • In dual-chamber MES, it was primarily acetoclastic methanogenic pathway. • In single-chamber MES cathode, hydrogenotrophic methanogenic pathway dominated. Microbial electrosynthesis (MES) is an advanced technology for efficient treatment of organic wastewater and recovery of new energy, with the advantages and disadvantages of single-chamber and dual-chamber MES reactors being less understood. Therefore, we explored the effects of single-chamber and dual-chamber structures on the methane production performance and microbial community structure of MES. Results indicated that methane concentration and current density of single-chamber MES were higher than those of dual-chamber MES, and the system stability was better, while chemical oxygen demand (COD) removal rate and cumulative methane production were not significantly different. Analysis of microbial community structure showed the abundance of acidogens and H 2 -producing bacteria was higher in single-chamber MES, while fermentation bacteria and methanogens was lower. The abundance of methanogens of dual-chamber MES (21.74–24.70%) was superior to the single-chamber MES (8.23–10.10%). Moreover, in dual-chamber MES, methane was produced primarily through acetoclastic methanogenic pathway, while in single-chamber MES cathode, methane production was mainly by hydrogenotrophic methanogenic pathway. Information provided will be useful to select suitable reactors and optimize reaction design. [ABSTRACT FROM AUTHOR]

Epithelial mesenchymal transformation plays a crucial role in the metastasis of bladder cancer, which makes bladder cancer difficult to cure. Bladder cancer is the most common malignancy of the urinary system, and distant metastasis is the leading cause of death. Therefore, finding a bioactive drug that can specifically inhibit epithelial mesenchymal transformation may be a new direction for bladder cancer treatment in the future. Thymoquinone (TQ), the major active compound isolated from black seed oil (Nigella sativa), has been reported to exhibit anti-inflammatory and anticancer abilities. TQ can exhibit its antitumor effect by inhibiting the proliferation and metastasis of cancer cells. However, the underlying mechanism of TQ as a tumor inhibitor in bladder cancer remains poorly understood. First, in this research, we demonstrate that TQ can reverse EMT by upregulating epithelial markers, such as E-cadherin, and downregulating mesenchymal markers, such as N-cadherin and vimentin. Furthermore, we demonstrate that TQ can suppress the activation of the Wnt/β-catenin signaling pathway and inhibit the expression of β-catenin target genes, such as MYC, Axin-2, MMP7, CyclinD1 and MET, which play crucial roles in EMT and cancer progression. Additionally, we demonstrate that TQ can inhibit the growth of xenografts and restrict the formation of tumor metastatic foci in the lung. Taken together, our findings confirm the antimetastatic effect of TQ in bladder cancer cells for the first time and also provide new evidence for the development of TQ as a novel treatment for metastatic bladder cancer. • Thymoquinone inhibits migration and invasion in bladder cancer cells. • Thymoquinone suppresses EMT in bladder cancer cells. • Thymoquinone inhibits the activation of Wnt/β-catenin signaling pathway. • β-catenin plays a key role in EMT inhibition induced by TQ. • Thymoquinone exerts an anti-metastasis effect of bladder cancer in vivo. [ABSTRACT FROM AUTHOR]

[Display omitted] • Methylators were dominating in rice rhizosphere, rather than the bulk soil. • Hg-promoted methylators are key taxa in the rhizosphere at the flowering stage. • In planta demethylation and methylation in rice roots are possible. • Desulfovibrionaceae may play an important role in Hg detoxification of rice. The plant microbiota can affect plant health and fitness by promoting methylmercury (MeHg) production in paddy soil. Although most well-known mercury (Hg) methylators are observed in the soil, it remains unclear how rice rhizosphere assemblages alter MeHg production. Here, we used network analyses of microbial diversity to identify bulk soil (BS), rhizosphere (RS) and root bacterial networks during rice development at Hg gradients. Hg gradients greatly impacted the niche-sharing of taxa significantly relating to MeHg/THg, while plant development had little effect. In RS networks, Hg gradients increased the proportion of MeHg-related nodes in total nodes from 37.88% to 45.76%, but plant development enhanced from 48.59% to 50.41%. The module hub and connector in RS networks included taxa positively (Nitrososphaeracea, Vicinamibacteraceae and Oxalobacteraceae) and negatively (Gracilibacteraceae) correlating with MeHg/THg at the blooming stage. In BS networks, Deinococcaceae and Paludibacteraceae were positively related to MeHg/THg, and constituted the connector at the reviving stage and the module hub at the blooming stage. Soil with an Hg concentration of 30 mg kg−1 increased the complexity and connectivity of root microbial networks, although microbial community structure in roots was less affected by Hg gradients and plant development. As most frequent connector in root microbial networks, Desulfovibrionaceae did not significantly correlate with MeHg/THg, but was likely to play an important role in the response to Hg stress. [ABSTRACT FROM AUTHOR]

Some thiols, such as cysteine (CYS) at moderate concentrations (10–500 µM), can enhance methylmercury (MeHg) formation by Geobacter sulfurreducens PCA, whereas others such as dithiol 2,3-dimercaptopropanesulfonate (DMPS) and 2,3-dimercaptosuccinic acid (DMSA) abolish mercury [Hg(II)] methylation. Little is known, however, about whether Hg(II) methylation could be enhanced or inhibited by the presence of mixed thiol ligands at low concentrations observed in the environment. Surprisingly we found that mixing CYS (1 µM) with DMPS (0.025–0.5 µM) or DMSA (0.025–1 µM) substantially increased MeHg production by 1.5–3.5-fold, compared to the no-thiol control, whereas complexation with a single DMPS, or DMSA, or CYS (1 µM) strongly inhibited Hg(II) methylation. Pre-equilibration between Hg(II) and thiols before the addition of cells was necessary to observe enhanced methylation. Spectroscopic analyses indicated the formation of mixed or heteroleptic coordinated Hg(II)-S 3 /S 4 complexes, which likely facilitated exchange of Hg(II) with cells and its uptake and internal transfer to the HgcAB proteins required for methylation. These results suggest that the effects of thiols on Hg(II) methylation were more complex than previously thought (using a single thiol) and thus underscore the importance of understanding how mixed thiols and their interactions with Hg(II) may ultimately influence MeHg production in the natural environment. [ABSTRACT FROM AUTHOR]

The microwave-assisted ionic liquid homogeneous liquid–liquid microextraction (MA-IL-HLLME) coupled with high performance liquid chromatography with diode array detection (HPLC-DAD) was developed for the determination of anthraquinones, including aloe-emodin, emodin, chrysophanol and physcion in root of Rheum palmatum L. Several experimental parameters influencing the extraction efficiency, including amount of sample, type and volume of ionic liquid, volume and pH value of extraction medium, microwave power and extraction time, concentration of NH 4 PF 6 as well as centrifugal condition were optimized. When 140 μL of ionic liquid ([C 8 MIM][BF 4 ]) was used as an extraction solvent, target analytes can be extracted from sample matrix in one minute with the help of microwave irradiation. The MA-IL-HLLME is simple and quick. The calibration curves exhibited good linear relationship ( r > 0.9984). The limits of detection and quantification were in the range of 0.015–0.026 and 0.051–0.088 μg mL −1 , respectively. The spiked recovery for each analyte was in the range of 81.13–93.07% with relative standard deviations lower than 6.89%. The present method is free of volatile organic solvents, and represents lower expenditures of sample, extraction time and solvent, compared with ultrasonic and heat reflux extraction. The results indicated that the present method can be successfully applied to the determination of anthraquinones in medicinal plant. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel fluorescent nanoplatform for acrolein detection based on AuNCs-MnO 2. • Used for on-site evaluation of acrolein scavengers' scavenging capacity. • Exhibits highly sensitivity and selectivity towards acrolein. • Combined with a smartphone for point-of-care detection of acrolein in real samples. • Successfully employed for imaging and detection of acrolein in biological cells. Acrolein is a high reactive and toxic aldehyde, commonly found in both dietary and environmental sources, and can also be produced endogenously. Given the highly toxicity of acrolein and its harmful effects on human health, many acrolein scavengers have been developed. However, a portable tool for on-site screening and evaluation of the capacity of acrolein scavengers is still rare. Herein, we have developed a fluorescence nanoplatform based on gold nanoclusters anchored to manganese dioxide (AuNCs-MnO 2) nanocomposites co-utilizing with glutathione (GSH) for rapid and sensitive detection of acrolein. In AuNCs-MnO 2 nanocomposites, MnO 2 quenched the fluorescence of AuNCs. GSH can reduce MnO 2 nanosheets to Mn2+, leading to the decomposition of MnO 2 and release of AuNCs, accompanied by the fluorescence recovery. When acrolein was present, GSH reacted specifically with acrolein through Michael addition. Simultaneously, the formation of GSH-acrolein adduct hindered the reduction of MnO 2 by GSH and the fluorescence recovery. The limit of detection (LOD) for acrolein was 0.082 μM. By constructing AuNCs-MnO 2 hydrogels with a smartphone, a point-of-care detection of acrolein in food samples and ambient air was achieved, obtaining satisfactory results with a recovery of 97.27–108.71 % and RSD of 1.27–4.33 %. The developed portable smartphone-based hydrogels also demonstrated strong potential on the on-site evaluation of acrolein scavengers' capacity. Furthermore, the nanoplatform was successfully applied to detect acrolein in living cells, providing a valuable reference for the diagnosis and treatment of acrolein-related diseases in clinical settings. [ABSTRACT FROM AUTHOR]

As a highly toxic aldehyde, acrolein is widely found in diet and environment, and can be produced endogenously, posing a serious threat to human health. Herein, we designed a novel fluorescent nanoplatform integrating carbon dots‑manganese dioxide (CDs-MnO 2) and glutathione (GSH) for all-in-one sensing and removal of acrolein. By converting Mn4+ to free Mn2+, GSH inhibited the inner filter effect (IFE) of MnO 2 nanosheets, and the Michael addition of acrolein with GSH inhibited the GSH-induced Mn4+ conversion, forming an "off-on-off" fluorescence response of CDs. The developed fluorescent nanoplatform exhibited high sensitivity (LOD was 0.067 μM) and selectivity for the simultaneous detection and removal of acrolein. The combination of CDs-MnO 2 hydrogels with smartphones realized the point-of-care detection of acrolein, yielding satisfactory results (recovery rates varied between 97.01–104.65%, and RSD ranged from 1.42 to 4.16%). Moreover, the capability of the nanoplatform was investigated for on-site evaluating acrolein scavengers' efficacy, demonstrating excellent potential for practical application. [Display omitted] • A novel fluorescent nanoplatform for acrolein detection based on CDs-MnO 2. • Used for all-in-one sensing and removal of acrolein. • Exhibits highly sensitivity and selectivity towards acrolein. • Combined with smartphones for on-site detection of acrolein in food and environment. • Successfully employed for imaging and detection of acrolein in living cells. [ABSTRACT FROM AUTHOR]

Rare earth elements (REYs) originate from the weathering of parent granite, whose clay-sized fractions are pivotal in the regolith-hosted rare earth elements (REEs) deposits. Regarding microbial action on REY mobilization and fractionation, their patterns remain unclear. Chemical extraction and bio-leaching experiments utilizing sulfate-reducing bacteria (SRB) were performed to exemplify the chemical and microbial effects on REY mobilization among the clay-sized phases. Our results indicate that the REYs occur primarily in the three fractions: i.e., amorphous Fe Mn phase, crystalline Fe phase, and carbonate in chemical reactors wherein the mineral phase was critical to the adsorption of REY. The 30-day SRB-leaching experiments led to an increase in the percentage of REY from 6% to 45% in the residue phase, implying that the residue phase, R Amor iron phase, and R Org phase hosted the REYs. The disorder of iron-bearing minerals, formation of iron-organic matters (Fe-OM), and secondary iron-bearing minerals represented a significant bio-leaching mechanism. Compared to chemical extraction, relatively higher MREY and HREY release efficiencies were obtained via bio-leaching, with average LREY/HREY ratios of 1.34–5.91 and 0.2–2.24 in chemical and bio-reactors, respectively. Our findings exhibited high potential microbial effects on the mobilization and fractionation of REY among mineral phases, offering real insights into the biogeochemical processes between minerals and bacteria. • With chemical extraction and bio-leaching experiments, REY-bearing clay-sized mineral phases were quantified. • REYs of the amorphous iron phase are easily separated by the chemical procedure. • Clay-sized REYs leached by the SRB are more readily released from the residue phase. • MREYs and HREYs are much more dissolved out than LREYs with the leaching of SRB. [ABSTRACT FROM AUTHOR]

• REEs in clay-sized fractions (CSFs) of sedimentary rocks were quantified. • Iron oxides and phyllosilicates were main REE hosts in CSFs of parent materials. • CSFs were REE sinks during carbonate rock weathering, with 2–3.8-fold enrichment. • REE patterns in CSFs recorded weathering for carbonate rock derived soils. • REEs in CSFs indicated provenance for clastic rocks derived soils. Rare earth elements (REEs) have gained attention as tracers of pedogenic processes over the last few decades. Clay-sized fractions (CSFs, < 2 μm) may play a crucial role in hosting REEs. To better understand the pedochemical signals of REEs in clay-sized phases, such as iron oxides and phyllosilicates, we analyzed REE speciation in CSFs of carbonate rocks (limestone), clastic rocks (sandstone and shale), and their derived saprolites. Our results quantified the REE content (41.2–144.6 mg kg−1) and speciation in CSFs of parent materials, revealing that REEs were primarily hosted in amorphous iron oxides (Fe ox1), followed by crystalline iron oxides (Fe ox2) and phyllosilicates. Compared to parent materials, saprolites derived from carbonate rocks exhibited more than a two-fold enrichment of REEs in major clay-sized phases, confirming the role of CSFs as REE sinks during carbonate rock weathering. Furthermore, the initial REE patterns of CSFs of carbonate rocks underwent alteration throughout the weathering process, likely due to water–mineral interactions. Our findings suggest that REEs in CSFs record the weathering fingerprint for soils derived from carbonate rocks, while they are indicative of provenance for soils originating from clastic rocks. [ABSTRACT FROM AUTHOR]

[Display omitted] • The methanogenic performance was better when the applied voltage was 0.8 V. • Clostrodium and Methanosaeta were the most dominant microbial populations. • MES-Cathode was more tolerant to the effects of higher NH 4 +-N concentration. • CH 4 was produced mainly via hydrogenotrophic methanogenic pathway in MES-Cathode. • MES produced CH 4 via SOAB, hydrogenotrophic archaea if acetoclastic pathway curbed. Microbial electrosynthesis (MES) has great potential for energy and resource recovery in wastewater treatment and has therefore gradually become a popular research topic. In this study, MES with an applied voltage (0.6 V, 0.8 V and 1.0 V) significantly improved biogas production (36.0 %, 52.3 %, and 59.1 %, respectively) compared with the control (without electrodes). Analysis of microbial community structure revealed that Clostridium and Methanosaeta had the highest relative abundance in all reactors. The abundances of Acetivibrio and Geobacter dominated the bioanode, and methane production was mainly mediated by the acetoclastic methanogenic pathway. On the biocathode, the abundances of Methanolinea and Methanothermobacter were higher than those of other microbes, and methane was produced primarily through the hydrogenotrophic methanogenic pathway. When the acetoclastic methanogenic pathway in the biocathode was inhibited, MES could efficiently produce methane through other pathways. In addition, MES was more tolerant to the effects of high NH 4 +-N concentrations than anaerobic digestion (AD). These results suggest that applying voltage to the bioanode and biocathode could better improve the efficiency of methane production. [ABSTRACT FROM AUTHOR]

Lead (Pb) is a widespread highly toxic and persistent environmental pollutant. Plant leaves play a key role in accumulating atmospheric Pb, but its distribution in different cells and subcellular structures and the factors affecting it have been little studied. Here, Tillandsia usneoides , an indicator plant for atmospheric heavy metals, was treated with an aerosol generation device to analyze Pb contents in different cells (three types of cells in leaf surface scales, epidermal cells, mesophyll cells, vascular bundle cells), subcellular structures (cell wall, cell membrane, vacuoles, and organelles) and cell wall components (pectin, hemicellulose 1 and 2, and cellulose). Results show the different cells of T. usneoides leaves play distinct roles in the process of Pb retention. The outermost wing cells are structures that capture external pollutants, while mesophyll cells, as the aggregation site after material transport, ring cells, disc cells, epidermal cells, and vascular cells are material transporters. Pb was only detected in the cell wall and pectin, indicating the cell wall was the dominant subcellular structure for Pb retention, while pectin was the main component affecting Pb retention. FTIR analysis of cell wall components indicated the esterified carboxyl (C O) functional group in pectin may function in absorbing Pb. Pb entered leaf cells mainly in the form of low toxicity and activity to enhance its resistance. [Display omitted] • Plant leaves are important atmospheric Pb sinks. • Different types of cells play different roles in Pb retention. • Cell wall is the main subcellular structure affecting atmospheric Pb retention. • Pectin is the main component affecting Pb retention in cell wall. • C O functional group is the main component affecting Pb retention in pectin. [ABSTRACT FROM AUTHOR]

Realizing accurate pesticide multiresidue detection in a complex matrix is still a challenge for point-of-care sensing methods. Herein, we introduced background-free and multicolor aptasensors based on bioorthogonal surface-enhanced Raman scattering (SERS) tags and successfully applied them to analyze multiple pesticide residues. The excellent anti-interference and multiplex capability are due to the application of three bioorthogonal Raman reporters involving 4-ethenylbenzenamine (4-EBZM), Prussian blue (PB) and 2-amino-4-cyanopyridine (AMCP) with alkynyl and cyano groups, which demonstrated apparent Raman shift peaks at 1993 cm−1, 2160 cm−1, and 2264 cm−1 in the biologically Raman-silent region, respectively. Ultimately, a detection range of 1–50 nM for acetamiprid, atrazine and malathion was achieved with detection limits of 0.39, 0.57 and 0.16 nM, respectively. The developed aptasensors were successfully used to determine pesticide residues in real samples. These proposed multicolor aptasensors offer an effective strategy for pesticide multiresidue detection with advantages of anti-interference, high specificity and high sensitivity. [Display omitted] • Aptasensors for Pesticide Multi-residues detection Using Bioorthogonal SERS tags. • Bioorthogonal tags demonstrated Raman peaks at 1993, 2160 and 2264 cm−1. • Aptasensors showed LODs of 0.39, 0.57 and 0.16 nM for three pesticides respectively. • Aptasensors were efficiently applied to detect pesticide multi-residues in real samples. [ABSTRACT FROM AUTHOR]

In this study, we propose an interference-free SERS-based aptasensor for trace detection of chlorpyrifos (CPF) in real samples. In the aptasensor, gold nanoparticles coated with Prussian blue (Au@PB NPs) were employed as SERS tags to provide a sole and intense Raman emission at 2160 cm−1, which could avoid overlapping with the Raman spectrum of the real samples in 600–1800 cm−1 to improve the anti-matrix effect ability of the aptasensor. Under the optimum conditions, this aptasensor displayed a linear response for CPF detection in the range of 0.1–316 ng mL−1 with a low detection limit of 0.066 ng mL−1. In addition, the prepared aptasensor shows excellent application to determine CPF in cucumber, pear and river water samples. The recovery rates were highly correlated with high-performance liquid chromatography‒mass spectrometry (HPLC‒MS/MS). This aptasensor shows interference-free, specific and sensitive detection for CPF and offers an effective strategy for other pesticide residue detection. Interference-free SERS-based Aptasensor for Chlorpyrifos Detection. [Display omitted] • An interference-free SERS aptsensor for chlorpyrifos residue detection was firstly developed. • PB containing CN was used as Raman report with a sole Raman emission in Raman-silent region (1800-2800 cm−1). • The aptsensor showed a linear detection range of 0.1–316 ng mL−1 with a LOD of 0.031 ng mL−1. • The aptsensor was successfully appiled to detect chlorpyrifos in real samples. [ABSTRACT FROM AUTHOR]

Previous research has found total mercury (THg) and methylmercury (MeHg) levels increase with litterfall decay, thus suggesting litterfall decomposition plays an essential role in the biogeochemical transformation of mercury (Hg). However, it remains unclear how Hg accumulates in the decaying litter, how bacterial taxa networks vary and what roles various microorganisms play during litterfall decomposition, especially nitrogen (N)-fixing, MeHg-degrading and Hg-methylating microbes. Here, we demonstrated as degradation proceeded, a gradually-complex network evolved for litterfall bacteria for the subtropical mixed broadleaf-conifer (MBC) forest, whereas a relatively static network existed for the evergreen broadleaf (EB) forest. N-fixing and MeHg-degrading bacteria dominated throughout litterfall decomposition process, with relative abundances of N-fixing genera and nifH copies maximum and relative abundances of MeHg-degrading bacteria and merAB copies minimum in summer. Hence, N-fixing bacteria likely mediate THg increase in the decomposing litterfall, while MeHg enhancement may be regulated by aerobic MeHg-degrading microbes which can transform MeHg to inorganic divalent Hg (Hg2+) or further to elemental Hg (Hg0). Together, this work elucidates variations of N-fixing and MeHg-degrading microbes in decaying litterfall and their relationships with Hg accumulation, providing novel insights into understanding the biogeochemical cycle of Hg in the forest ecosystem. [Display omitted] • A gradually-complex network evolved for the decaying litterfall of MBC forest. • A relatively static network existed for the decomposing EB forest litterfall. • N-fixing bacteria may mediate the increase of THg levels in the decomposing litterfall. • MeHg enhancement is likely regulated by aerobic MeHg-degrading microbes. • Underlying soil is the source of litterfall THg, while MeHg is transported from litterfall to soil. [ABSTRACT FROM AUTHOR]

To strengthen mass heat transfer in dry fermentation and avoid the high shear forces breaking microbial flora. A reactor is designed to rotate itself instead of mechanical stirring. Its performance was verified by comparing it with the common stirring of dry digestion and wet digestion. The results showed that the designed reactor could effectively overcome the existing problems of stirring dry digestion. The total solids removal rate was up to 68.74%, which was 18% higher than that of wet digestion. Acetic acid and propionic acid were the main volatile fatty acids in dry digestion, and acetic acid and butyric acid were higher in wet digestion. The high diversity of fermentation bacteria integrated with hydrotrophic methanogens in the designed dry reactor resulted in its better performance. The information provided will be useful to research the anaerobic treatment of solid municipal waste. • A reactor used rotating instead of stirring was designed for dry fermentation. • The designed reactor performed well in the dry fermentation of kitchen waste. • More functional bacteria and hydrotrophic methanogens lead to good fermentation. • Methahnosarcina dominated in both designed dry reactor and common wet reactor. • Proteiniphilum and Enterococcus dominated in the designed reactor. [ABSTRACT FROM AUTHOR]

• The solubility of marbofloxacin in binary solvents was measured by a dynamic laser monitoring method. • Experimental data was correlated with the modified Apelblat, λh, and NRTL models. • A model proposed by Jain et al. was employed to estimate the fusion enthalpy of marbofloxacin. • The dissolution behavior of marbofloxacin in different binary solvent systems was discussed. • Ethanol + water solvent system is considered to be the most suitable crystallization reagent. Marbofloxacin (MAB) is a broad-spectrum veterinary antibacterial drug with the great application prospects. The solid-liquid equilibrium solubility of MAB in three kinds of aqueous binary solvent systems (ethanol + water, acetonitrile + water, and methanol + water) was determined between 283.15 and 323.15 K using a dynamic laser-monitoring method at atmospheric pressure. The experimental results revealed that the solubility of MAB increased with increasing temperature and mole fraction of water in the three binary solvent systems. The modified Apelblat, λh, and (non-random two-liquid) NRTL models were used to correlate the experimental data. For the ethanol + water system, the modified Apelblat model provided a better correlation with the experimental results than the other two models. However, for the acetonitrile + water and methanol + water systems, the most favorable correlation was obtained using the NRTL model. Furthermore, the van't Hoff equation was used to study the thermodynamic properties of MAB. The obtained solubility data and thermodynamic properties of MAB can provide theoretical guidance for selecting the appropriate solvent system for the reaction, crystallization, and purification of MAB. [ABSTRACT FROM AUTHOR]

Abstract: Electroenzymatic oxidation is an interesting approach that combines enzyme catalysis and electrode reactions. The catalytic oxidation of bisphenol-A (BPA) by an electroenzymatic method using the immobilized horseradish peroxidase (HRP) was investigated in a membraneless electrochemical reactor. To introduce HRP in the membraneless electrochemical reactor, the silk fibroin and poly (amido amine) (PAMAM) were covalently bonded onto the magnetic Fe3O4 nanoparticles to give an aminated magnetic silk fibroin nanoparticle for immobilize HRP. To evaluate the electroenzymatic degradation of bisphenol-A, electrolytic experiments were carried out with 0.5U/mL HRP at applied potential 1.6V, pH 5.0, 25°C and oxygen flow rate 25mL/min, respectively. Under the optimum condition, the removal efficiency of bisphenol-A reached 80.3%. Compared with other methods, the bisphenol-A was degraded more effectively through electroenzymatic process. The results obtained in this work provided theoretical basis for the practical application of the electroenzymatic process in the treatment of organophosphorus compounds in wastewater. [Copyright &y& Elsevier]

A mild ischemic stroke may cause both debilitating locomotor and cognitive decline, for which the mechanism is not fully understood, and no therapies are currently available. In this study, a nonfatal stroke model was constructed in mice by a modified middle cerebral artery occlusion (MCAO) procedure, allowing an extended recovery period up to 28 days. The extended MCAO model successfully mimicked phenotypes of a recovery phase post-stroke, including locomotor motor and cognitive deficiencies, which were effectively improved after Shuxuening injection (SXNI) treatment. Tissue slices staining showed that SXNI repaired brain injury and reduced neuronal apoptosis, especially in the hippocampus CA3 region. Transcriptomics sequencing study revealed 565 differentially expressed genes (DEGs) in the ischemic brain after SXNI treatment. Integrated network pharmacological analysis identified Neurotrophin/Trk Signaling was the most relevant pathway, which involves 15 key genes. Related DEGs were further validated by RT-PCR. Western-blot analysis showed that SXNI reversed the abnormal expression of BDNF, TrkB, Mek3 and Jnk1after stroke. ELISA found that SXNI increased brain level of p-Erk and Creb. At sub-brain level, the expression of BDNF and TrkB was decreased and GFAP was increased on the hippocampal CA3 region in the post-stroke recovery phase and this abnormality was improved by SXNI. In vitro experiments also found that oxygen glucose deprivation reduced the expression of BDNF and TrkB, which was reversed by SXNI. In summary, we conclude that SXNI facilitates the recovery of cognitive and locomotor dysfunction by modulating Neurotrophin/Trk Signaling in a mouse model for the recovery phase of post-ischemic stroke. [Display omitted] [ABSTRACT FROM AUTHOR]

• SXNI facilitated neurofunctional recovery in subacute stroke mice. • SXNI inhibited granulocyte adhesion and diapedesis pathway in subacute stroke mice. • SXNI down-regulated the expression of G-csf and its downstream E-selectin and Mac-1. Post-stroke neural damage is a serious health concern which does not yet have an effective treatment. We have shown previously that Shuxuening injection (SXNI), a Ginkgo biloba extract-based natural medicine, protects brain after an acute ischemic stroke, but its efficacy for post-stroke recovery is not known. This study was to investigate whether SXNI can improve the prognosis of stroke at a subacute phase. Mice with cerebral ischemia-reperfusion injury (CIRI) were established by middle cerebral artery occlusion (MCAO), and drugs or saline were injected by the tail vein every 12 h after reperfusion. The therapeutic effect of SXNI was evaluated by survival rate, modified neurologic severity scores (mNSS), open-field test, locomotive gait patterns, cerebral infarction volume, brain edema and histopathological changes. Subsequently, a combined method of RNA-seq and Ingenuity® Pathway Analysis (IPA) was performed to identify key targets and pathways of SXNI facilitating the prognosis of stroke in mouse brain. The results of the transcriptome analysis were verified by real time reverse transcription-polymerase chain reaction (RT-PCR), enzyme-linked immunosorbent assay (ELISA), western blot (WB) and immunohistochemistry (IHC). The experimental results showed that in the new subacute stroke model, SXNI markedly improves the survival rate, neurological and motor functions and histopathological changes, and significantly reduces cerebral infarction and edema volume. RNA-seq analysis of subacute stroke mice with or without SXNI (3 mL/kg) indicated 963 differentially expressed genes (DEGs) with a fold change ≥ 1.5 and a P-value ≤ 0.01. IPA analysis of DEGs showed that granulocyte adhesion and diapedesis ranked first in the pathway ranking, and the most critical gene regulated by SXNI was G-csf. Simultaneously, RT-PCR, ELISA, WB and IHC results demonstrated that SXNI not only obviously reduced the mRNA expression levels of key genes G-csf , Sele and Mac-1 in this pathway, but also significantly decreased the protein expression levels of G-CSF in serum and E-selectin and MAC-1 in brain tissues. In summary, our research suggested that SXNI can exert a remarkable neurofunctional therapeutic effect on stroke mice via down-regulating G-CSF to inhibit granulocyte adhesion and diapedesis. This study provides experimental evidence that SXNI may fulfill the need for stroke medicine targeting specifically at the recovery stage. [ABSTRACT FROM AUTHOR]