28 research outputs found

    Aerobic Denitrification Is Enhanced Using Biocathode of SMFC in Low-Organic Matter Wastewater

    No full text
    Nitrate (NO3−) in wastewater is a rising global threat to ecological and health safety. A sufficient carbon source, as the electron donor, is essential in the conventional biological denitrification process. It is not appropriate to add extra carbon sources into specific water bodies in terms of material cost and secondary pollution. Thus, innovative NO3− removal technologies that are independent of carbon sources, are urgently needed. This study constructed sediment microbial fuel cells (SMFCs) for aerobic denitrification in low-organic matter wastewater and explored the key factors affecting denitrification efficiencies. The SMFC treatments removed 72–91% NO3− through two main denitrifying stages which were driven by carbon sources (COD) and generated electrons, respectively. After COD was fully consumed, denitrification efficiencies were enhanced in SMFC treatments by 24–47% using the generated electrons within 3 days. In this stage, the NO3− removal efficiencies were positively correlated with external current intensities (p < 0.05). The improved denitrification efficiencies were attributed to two enriched phyla in the SMFC cathode. The dominant genera also demonstrated the heterotrophic denitrifying capacity of the SMFC biocathode. Furthermore, electrical characteristics could be used to monitor or regulate the denitrification process in the SMFC system. In conclusion, this study presents an innovative treatment strategy that is economical and eco-friendly compared with conventional physicochemical methods

    Aerobic Denitrification Is Enhanced Using Biocathode of SMFC in Low-Organic Matter Wastewater

    No full text
    Nitrate (NO3&minus;) in wastewater is a rising global threat to ecological and health safety. A sufficient carbon source, as the electron donor, is essential in the conventional biological denitrification process. It is not appropriate to add extra carbon sources into specific water bodies in terms of material cost and secondary pollution. Thus, innovative NO3&minus; removal technologies that are independent of carbon sources, are urgently needed. This study constructed sediment microbial fuel cells (SMFCs) for aerobic denitrification in low-organic matter wastewater and explored the key factors affecting denitrification efficiencies. The SMFC treatments removed 72&ndash;91% NO3&minus; through two main denitrifying stages which were driven by carbon sources (COD) and generated electrons, respectively. After COD was fully consumed, denitrification efficiencies were enhanced in SMFC treatments by 24&ndash;47% using the generated electrons within 3 days. In this stage, the NO3&minus; removal efficiencies were positively correlated with external current intensities (p &lt; 0.05). The improved denitrification efficiencies were attributed to two enriched phyla in the SMFC cathode. The dominant genera also demonstrated the heterotrophic denitrifying capacity of the SMFC biocathode. Furthermore, electrical characteristics could be used to monitor or regulate the denitrification process in the SMFC system. In conclusion, this study presents an innovative treatment strategy that is economical and eco-friendly compared with conventional physicochemical methods

    Effects of Electrical Stimulation on the Degradation of Azo Dye in Three-Dimensional Biofilm Electrode Reactors

    No full text
    Three-dimensional biofilm electrode reactors (3D-BERs) were constructed to degrade the azo dye Reactive Brilliant Red (RBR) X-3B. The 3D-BERs with different influent concentrations and external voltages were individually studied to investigate their influence on the removal of X-3B. Experimental results showed that 3D-BERs have good X-3B removal efficiency; even when the influent concentration was 800 mg/L, removal efficiency of 73.4% was still achieved. In addition, the X-3B removal efficiency stabilized shortly after the influent concentration increased. In 3D-BERs, the average X-3B removal efficiency increased from 52.8% to 85.4% when the external voltage rose from 0 to 2 V. We further identified the intermediate products via UV-Vis and gas chromatography-mass spectrometry (GC-MS) analyses, and discussed the potential mechanism of degradation. After the conjugate structure of X-3B was destroyed, all of the substances generated mainly consisted of lower-molecular-weight organics

    N1-Guanyl-1,7-Diaminoheptane Sensitizes Estrogen Receptor Negative Breast Cancer Cells to Doxorubicin by Preventing Epithelial-Mesenchymal Transition through Inhibition of Eukaryotic Translation Initiation Factor 5A2 Activation

    No full text
    Background: Approximately 30% of breast cancer does not express the estrogen receptor (ER), which is necessary for endocrine-based therapy approaches. Many studies demonstrated that eukaryotic translation initiation factor 5A2 (eIF5A2) serves as a proliferation-related oncogene in tumorigenic processes. Methods: The present study used cell viability assays, EdU incorporation assays, western blot, and immunofluorescence to explore whether N1-guanyl-1,7-diaminoheptane (GC7), which inhibits eIF5A2 activation, exerts synergistic cytotoxicity with doxorubicin in breast cancer. Results: We found that GC7 enhanced doxorubicin cytotoxicity in ER-negative HCC1937 cells but had little effect in ER-positive MCF-7 and Bcap-37 cells. Administration of GC7 reversed the doxorubicin-induced epithelial-mesenchymal transition (EMT) in ER-negative breast cancer cells. Knockdown of eIF5A2 by siRNA inhibited the doxorubicin-induced EMT in ER-negative HCC1937 cells. Conclusion: These data demonstrated that GC7 combination therapy may enhance the therapeutic efficacy of doxorubicin in estrogen negative breast cancer cells by preventing EMT through inhibition of eIF5A2 activation

    Chidamide suppresses adipogenic differentiation of bone marrow derived mesenchymal stem cells via increasing REEP2 expression

    No full text
    Summary: Increased propensity of bone marrow-derived mesenchymal stem cells (BM-MSCs) toward adipogenic differentiation at the expense of osteogenesis has been implicated in obesity, diabetes, and age-related osteoporosis as well as various hematopoietic disorders. Defining small molecules with role in rectifying the adipo-osteogenic differentiation imbalance is of great significance. Here, we unexpectedly found that Chidamide, a selective histone deacetylases inhibitor, exhibited remarkably suppressive effect on the in vitro induced adipogenic differentiation of BM-MSCs. Multifaceted alterations in the spectrum of gene expression were observed in Chidamide-managed BM-MSCs during adipogenic induction. Finally, we focused on REEP2, which presented decreased expression in BM-MSCs-mediated adipogenesis and was restored by Chidamide treatment. REEP2 was subsequently demonstrated as a negative regulator of adipogenic differentiation of BM-MSCs and mediated the suppressive effect of Chidamide on adipocyte development. Our findings provide the theoretical and experimental foundation for the clinical application of Chidamide for disorders associated with excessive marrow adipocytes
    corecore