Unveiling the correlation between the catalytic efficiency and acidity of a metal-free catalyst in a hydrogenation reaction. A theoretical case study of the hydrogenation of ethene catalyzed by a superacid arising from a superhalogen.

A systematic quantum-chemical study of the hydrogenation of ethene, catalyzed by strong acids HX (X = F, Cl, Br) and superacids HA (A = MgX3, Mg2X5; X = F, Cl, Br) arising from octet superhalogens is explored. Two possible paths are proposed, concerted and stepwise, and the calculated results show that the concerted path is more favorable than the stepwise path. Compared to the hydrogenation reaction without any catalyst, the improvement of the catalytic efficiency of the superacid HA (A = MgX3, Mg2X5) is high, up to 38.8 to 59.4%. Compared to the strong acid HX (X = F, Cl, Br), the barrier energy is significantly reduced and the improvement of the catalytic efficiency of the superacid HA reaches 23.1 to 31.7%. In particular, for HMg2Br5, the barrier energy of the hydrogenation of ethene is only 36 kcal mol-1, which shows that the reaction could proceed under experimental conditions. In addition, the results show that the catalytic efficiency of the superacid HA is related to the acidity of the superacid. In general, the greater the acidity, the lower the barrier energy and the easier the hydrogenation reaction. From the analysis of the bond order, the newly formed C-H bond of the transition state (TS3) in the concerted path, in which the H atom comes from the superacid catalyst, directly affects the barrier energy of the entire reaction. For the more acidic catalyst, this H atom is provided more easily, and then the formed C-H bond in the transition state is stronger. Consequently, this stronger bond leads to a more stable transition state, and hence to a lower energy barrier as well as a higher efficiency of the superacid catalyst. Therefore, a positive correlation between the acidity of the metal-free catalyst and its catalytic efficiency is expected in the hydrogenation reaction.

[Pollution Characteristics and Risk Assessment of PAHs in the Soil of Wild Forsythia Suspensa in Shanxi].

Shanxi is one of the main producing areas of Forsythia suspensa in China. In order to explore the safety of the soil in the areas where Forsythia suspensa grows,70 surface (0-25 cm) soil samples were collected from the main growing areas of F. suspensa in the eastsouth of Shanxi Province in July 2017. The concentration and composition characteristics of 16 polycyclic aromatic hydrocarbons (PAHs) in the sample soils were analyzed using chemical extraction and gas chromatography-mass spectrometry (GC-MS). The diagnostic ratio method was used to determine the source of PAHs in the areas. The potential ecological risk was assessed by using the method of calculating the equivalent carcinogenic concentration of benzo[a]pyrene. The results showed that the average concentration of total PAHs (Σ16PAHs) in all of the soil samples was 1.85 µg·g-1, which was dominated by three ring number PAHs, accounting for 76.7% of the total PAHs. The detection rates of phenanthrene (Phe) and anthracene (Ant) were both 100% of all the sample sites. The soil PAHs in the wild F. suspensa growing areas mainly originated from coal, biomass burning, and motor vehicle exhaust emissions, which resulted from air transport and sedimentation pathways. In all of the sample sites, the concentration of Σ16PAHs the limit standard level (0.2 µg·g-1) of Maliszewska-Kordybach for agricultural soil pollution and exceeded the soil heavy pollution level limit value (1.0 µg·g-1) in 41.4% of the sample sites. The concentration of BaP was above the risk control standard for soil contamination of agricultural land (0.55 µg·g-1) in 10% of all the soil samples. A total of 11.4% of the sample soil ΣBaPeq16PAHs and ΣBaPeq8BPAHs exceeded the agricultural soil screening value (0.55 µg·g-1). These results indicate that the contamination of PAHs was at a detectable level in the soil of wild F. suspensa growing in Shanxi, and thus their potential ecological risks should not be ignored. It is necessary to enhance the research regarding these areas to ensure the safe production of medicinal plants.

[Pollution Characterization and Comprehensive Water Quality Assessment of Rain-source River: A Case Study of the Longgang River in Shenzhen].

Rain-source urban rivers are an important part of the urban ecosystem. Due to the small water environment capacity and the rapid development of the regional economy and society, they are vulnerable to serious pollution. The goal of this study was to identify the main pollution characteristics of river water quality and to carry out a scientific comprehensive water quality assessment. Water samples from 12 sampling locations of the Longgang River in Shenzhen, a typical rain-source urban river, were collected from January to December in 2018. According to the Environmental Quality Standard for Surface Water (GB 3838-2002), 22 water quality indicators were analyzed, and the water quality of Longgang River was comprehensively evaluated using the single-factor assessment method, comprehensive pollution index method, and principal component analysis method. The results of the single-factor assessment method showed that water quality of all sampling sites of the Longgang River met the Class V of the Environmental Quality Standard for Surface Water (GB 3838-2002), and the Tiaojiao Shui and Longxi River met the Class Ⅳ and Class Ⅲ of the Environmental Quality Standard for Surface Water (GB 3838-2002), respectively. The results of the comprehensive pollution index method showed that the water quality of 12 sampling sites was clean or relatively clean. Both the results of the comprehensive pollution index and principal component comprehensive score showed that the water quality of Longxi River, Nanyue River, and Tianjiao Shui were the best among all sampling sites. There is still room for improvement in the Wutongshan River, Dakang River, Ailian River, Dingshan River, and Huangsha River, and significant consideration should be given to parameters such as nutrients (TN, TP, and NH4+-N), organic matter (COD and BOD5), fecal coliform, and anionic surfactants. The three methods were a combination of qualitative and quantitative evaluation. The results of each method were not identical. Thus, it is very necessary to explore the comprehensive water quality assessment using various methods for making scientific and reasonable water pollution control strategies.

[Effects of Nano-membrane on Aerobic Composting Process and Odor Emission of Livestock Manure].

Aerobic composting is an important approach to treat livestock manure; however, traditional composting has some problems, such as low efficiency, or odorous pollution. In order to speed up the composting process and reduce malodorous gas emissions, this study explored the mechanism of nano-membrane for improving the efficiency of livestock manure composting. A trough aerobic composting experiment was set up to evaluate the physicochemical properties, enzyme activities, and emission of odorous gases. The results showed that covering with nano-membrane could accelerate the temperature rise; reduce the pH, organic matter(OM), and ammonia nitrogen(NH4+-N); increase electrical conductivity(EC); enhance the activities of urease, protease, cellulase, xylanase, and peroxidase; while the total cumulative emissions of NH3, H2S, and TVOC were reduced by 58%, 100%, and 61%, respectively. The correlation analysis showed that most enzyme activities were easily affected by temperature(T), EC, OM, and C/N. The emission rate of NH3 was positively correlated with T and negatively correlated with pH, and TVOC was significantly correlated with various physicochemical properties. This experiment showed that covering nano-membrane could accelerate the compost maturity and reduce the emission of odorous gases. This approach has no health risks and produces low malodorous gas, which may effectively solve the problem of pollutant emission caused by livestock manure compost fermentation, promoting the green and sustainable development of the breeding industry. In addition, it facilitates livestock manure fertilizer application, and provides technical support for the development of resource utilization of biomass waste.

Generation of a laminopathies-specific iPSC line EHTJUi005-A-3 with homozygous knockout of the LMNA gene by CRISPR/Cas9 technology.

LAMIN A/C, encoded by the LMNA gene, supports the normal structure of the cell nucleus and regulates the connection between the nucleus and the cytoskeleton as a component of the nucleus envelope. The loss of expression and function of the LMNA gene would lead to the occurrence of congenital muscular dystrophy and Emery-Dreifuss muscular dystrophy which are collectively named as laminopathies. Here, we report a human induced pluripotent stem cell (iPSC) line (EHTJUi005-A-3) generated from a wild iPSC (EHTJUi005-A) with homozygous knockout of the gene LMNA through CRISPR/Cas9. This iPSC line provides a useful research model for studying laminopathies disease.

CRISPR/Cas9 mediated generation of a iPSC line EHTJUi005-A-1 with homozygous knockout of the SUV39H1 gene.

SUV39H1 is a histone methyltransferase involve numerous biological processes, including of aging, embryo development, tumor growth and mitosis via catalysis of dimethylation and trimethylation of lysine 9 of histone H3. Here we report a human induced pluripotent stem cell line (EHTJUi005-A-1) which is generated from a wildtype human iPSC previously established in our laboratory, and this iPSC has a homozygous knockout of 8 bp in Exon 2 of SUV39H1. This iPSC model provides a valuable resource to study epigenetic regulation in extensive biological processes as mentioned above.

An induced pluripotent stem cell line (EHTJUi003-A) generated from a neonate with c.1377delC mutation in the gene MYBPC3 causing hypertrophic cardiomyopathy.

Hypertrophic cardiomyopathy (HCM) is an autosomal dominant heart disease. An induced pluripotent stem cell line (EHTJUi003-A) was generated from umbilical cord blood mononuclear cells (UCBMCs) of a female neonate with heterozygous mutation of p.L460Wfs (c.1377delC) in the MYBPC3 gene. This iPSC model offers a very valuable resource to study the pathological mechanism of HCM in vitro.

An induced pluripotent stem cell line (EHTJUi004-A) generated from a neonate with c.4683_4684delCT:p.Leu1563fs mutation in the gene DSP causing Familial Arrhythmogenic Right Ventricular Dysplasia (ARVD).

Familial Arrhythmogenic Right Ventricular Dysplasia (ARVD) is a primary cardiomyopathy characterized by the abnormality of the right ventricular muscle. ARVD may be life-threatening due to the induction of paroxysmal refractory ventricular tachycardia or supraventricular arrhythmia. A human induced pluripotent stem cell line (EHTJUi004-A) was generated from human umbilical cord blood mononuclear cells (UCBMCs) of a female neonate with heterozygous mutation of p.Leu1563fs (c.4683_4684delCT) in the DSP gene. This iPS cell line resource provides an ideal in vitro model to study the pathological mechanism of ARVD.

[Biodegradation of Expanded Polystyrene Foams in Zophobas morio: Effects of Gut Microbiota].

Polystyrene (PS) foam is one of the main plastic materials dispersed in the environment. In this study, we observed that the insect-super mealworms (Zophobas morio), which belong to a species of the Tenebrio genus, are able to consume and degrade PS foam. Individual Z. morio consumed an extracellular polymeric substance (EPS) over 50 days with high survival rates. Analyses of the frass egested using fourier transform infrared spectroscopy (FTIR) confirmed the formation of a new oxygen-bearing functional group in the EPS. Gel permeation chromatography (GPC) analyses indicated that the depolymerization of ingested EPS with decreases in both Mw and Mn was observed, suggesting that the EPS was biodegraded. We also used 16S rRNA gene sequences to analyze the gut bacteria of Z. morio under three different feeding conditions, including with polystyrene, bran, and bran plus polystyrene. Under different dietary conditions, the gut microbiota of Z. morio showed significant differences, such as Klebsiella and Citrobacter becoming significantly enriched. In vitro studies using 90-days gut microbial culturing experiments indicated that gut microbiota contributed to PS degradation. Our research demonstrates that intestinal bacteria played an essential role in the degradation of PS by Z. morio, and provides a new theoretical basis and application ideas for the biodegradation of PS.

[Bacillus amyloliquefaciens Biofertilizer Mitigating Soil Ammonia Volatilization].

In this study, we investigated the effectiveness and microbial mechanism of Bacillus amyloliquefaciens biofertilizer on reducing ammonia volatilization in farmland soil. Pot experiments were carried out to explore the effects of B. amyloliquefaciens biofertilizer (BB) and chemical fertilizer on soil ammonia volatilization, crop yield and quality, and soil microbial community. Four fertilization strategies were tested, namely no fertilizer (CK), 100% chemical fertilizer (C), 50% BB and 50% chemical fertilizer (B1), and 100% BB (B2). The dynamic flow-through chamber method was used to determine the soil ammonia volatilization flux after fertilization. The soil bacterial community during the peak period of ammonia volatilization was analyzed using 16S rDNA high-throughput sequencing. The results showed that the amount of ammonia volatilization in B1 and B2 decreased by 79.5% and 84.8%, respectively, as compared with treatment C. B2 had the lowest nitrate content and the highest yield; the yield of B2 increased by 50.5% and 12.3% as compared to that of CK and C, respectively. B1 had the highest content of vitamin C, which was 67.6 mg ·kg-1. The application of BB improved the diversity and richness of soil bacterial community, especially the relative abundance of Bacillus and Nitrospira. This shows that BB plays an important role in preventing air pollution and improving nitrogen utilization.

An induced pluripotent stem cell line (EHTJUi002-A) derived from a neonate with c.678G>A mutation in the gene FZD4 causing exudative vitreoretinopathy.

Familial exudative vitreoretinopathy (FEVR) is an autosomal dominant genetic disease. An induced pluripotent stem cell line (EHTJUi002-A) was generated from umbilical cord blood mononuclear cells (UCBMCs) of a neonate with heterozygous mutation of p.W226X(c.678G>A) in the FZD4 gene. This iPSC model offers a very valuable resource to study the pathological mechanism of FEVR in vitro.

[Characteristics of Nitrogen Metabolism by Denitrifying Bacterial Agents in Low Dissolved Oxygen Black Odor Water].

In order to deal with low dissolved oxygen black odor water body of Guangdong-Hong Kong-Macao Greater Bay Area, the nitrogen metabolic capacity of ammoniated bacteria, nitrifying bacteria and denitrifying bacteria under low dissolved oxygen concentration was studied, and the relationship between denitrification efficiency and nitrogen conversion of different bacteria was clarified, which provided theoretical basis for the treatment of black odor water of Guangdong-Hong Kong-Macao Greater Bay Area. Nitrogen conversion characteristics of ammoniated bacteria (Staphylococcus sp. Ay), nitrifying bacteria (Microbacterium sp. Xw), and denitrifying bacteria (Arthrobacter sp. Fy) in simulated wastewater were detected by different concentration of bacteria and different concentration of substrates. The nitrogen metabolism of Ay, Xw and Fy in black odor water at the same concentration under low dissolved oxygen condition and the characteristics of nitrogen metabolism in different concentrations of black odor water were studied. The results showed that the bacterial concentration of Ay bacterium agent increased three times, but the ammoniation efficiency did not multiply. It indicated that increasing the concentration of ammoniated bacterium was not the best way to increase the ammoniation rate. Xw bacteria have a significant effect on the change of nitrate concentration. At 60 h, the nitrate concentration was increased 180% at low bacterial concentration, was 231% at a high bacterial concentration. Fy denitrification efficiency was high, that nitrate nitrogen can be removed quickly at lower concentration. Appropriate increase of total nitrogen concentration can increase the ammoniation efficiency of Ay microbial agent, but too high would inhibit the nitrogen metabolism efficiency of Ay microbial agent. The concentration of nitrate nitrogen of Xw bacterium reagent was increased (3736%) when the total nitrogen was 25 mg·L-1. The Fy microbial agent has no obvious effect on ammonia nitrogen removal. When the total nitrogen concentration was 25 mg·L-1, the removal rate of nitrate by Fy bacterium was the best. Overall, the results showed that the concentration of ammoniated bacteria and denitrifying bacteria could meet the need of nitrogen metabolism, and the nitrifying bacteria could increase the nitrate nitrogen synthesis rate with the increase of the concentration of nitrifying bacteria. In a certain range, increasing the concentration of substrate could increase the efficiency of nitrogen metabolism of bacterial agents, and excessive concentration would inhibit the effect of nitrogen metabolism. The study provides data support for the problem of black odor water in Guangdong-Hong Kong-Macao Greater Bay Area.

[Allelopathic Effects and Allelochemicals of Myriophyllum elatinoides on Microcystis aeruginosa and Selenastrum capricornutum].

The allelopathic effects of Myriophyllum elatinoides on algal growth were investigated and potential allelochemicals secreted by Myriophyllum elatinoides were analyzed. Myriophyllum elatinoides were co-cultivated with different initial concentrations (105, 106, 107, 108, and 109 ind.·L-1) of Microcystis aeruginosa and Selenastrum capricornutum. The optical density of each group was measured daily. The results showed that 2.5 g·(200 mL)-1 of Myriophyllum elatinoides has significant inhibition effect on Microcystis aeruginosa growth with initial concentrations of 107 ind.·L-1 and 108 ind.·L-1. However, there was no significant inhibition on the growth of Selenastrum capricornutum. Through solvent extraction and GC-MS analysis, hexadecanoic acid was extracted and determined as an allelochemical in Myriophyllum elatinoides. Additionally, three potentially novel allelochemical compounds secreted by Myriophyllum elatinoides were determined as follows:3-ethyl-3-methylheptane, triethyl phosphate and dibutyl phthalate.

[Evaluation of the Potential Agricultural Risks of Polycyclic Aromatic Hydrocarbon Contaminated Soil by Planting Lactuca sativa L.]

In order to evaluate the potential agricultural risks of soil contaminated by polycyclic aromatic hydrocarbons (PAHs), Lactuca sativa L. was used as a model leaf vegetable plant to investigate the enrichment characteristics of PAHs in the different tissues of Lactuca sativa L, such as its underground parts (GS) and aboveground parts (YS), which were studied through an experiment involving potted cultivation in PAHs contaminated soil that was taken from the agricultural soil around a coking enterprise area. The concentrations of the different PAHs in the soil and plant tissues were analyzed using ultrasonic oscillation extraction and high-performance liquid chromatography-mass spectrometry (GC-MS) analysis methods. The results show that the enrichment of the total PAHs (Σ16PAHs) in the YS is higher than that in the GS. The components enriched in the YS mainly consist of 3-5 ring PAHs, and those in the GS consist of 4-6ring PAHs. The coefficients of the different PAHs enriched in the YS were higher than those of the GS. The enrichment coefficient of anthracene (Ant) was the largest and that of fluoranthene (Fla) was the smallest in the YS, while the enrichment coefficient of benzene[a]pyre (Bap) was the largest and that of Fla was the smallest in the GS. The transfer coefficients of the different PAHs from the GS to the YS were greater than the rate from the initial soil (SS) to the GS; the value is less than 1 from the SS to GS. The correlations and goodness of fit were analyzed for the concentrations of PAHs in the SS, GS and YS. The Σ16PAHs in the SS showed positive correlations with the Σ16PAHs in the YS and in GS. The goodness of fit of the correlation of the PAHs in YS to those in the SS was the largest (R2=1.0), while the goodness-of-fit for the correlation between the GS and SS was lower (R2=0.71). The benzo[a]pyrene equivalent concentration values (Σ16PAHsBapeq) of YS and GS were 11.8 and 12.7 times the maximum value of Bap level allowed in food. The study indicates that contaminated farmland soil would present a high health risk when it was used to grow the plant.

A novel matrine derivate inhibits differentiated human hepatoma cells and hepatic cancer stem-like cells by suppressing PI3K/AKT signaling pathways.

Matrine is an alkaloid extracted from a Chinese herb Sophora flavescens Ait, which has shown chemopreventive potential against various cancers. In this study, we evaluated the anticancer efficacy of a novel derivative of matrine, (6aS, 10S, 11aR, 11bR, 11cS)-10- methylamino-dodecahydro- 3a,7a-diazabenzo (de) (MASM), against human hepatocellular carcinoma (HCC) cells and their corresponding sphere cells in vitro and in vivo. Human HCC cell lines (Hep3B and Huh7) were treated with MASM. Cell proliferation was assessed using CCK8 and colony assays; cell apoptosis and cell cycle distributions were examined with flow cytometry. The expression of cell markers and signaling molecules was detected using Western blot and qRT-PCR analyses. A sphere culture technique was used to enrich cancer stem cells (CSC) in Hep3B and Huh7 cells. The in vivo antitumor efficacy of MASM was evaluated in Huh7 cell xenograft model in BALB/c nude mice, which were administered MASM (10 mg·kg-1·d-1, ig) for 3 weeks. After the treatment was completed, tumor were excised and weighed. A portion of tumor tissue was enzymatically dissociated to obtain a single cell suspension for the spheroid formation assays. MASM (2, 10, 20 µmol/L) dose-dependently inhibited the proliferation of HCC cells, and induced apoptosis, which correlated with a reduction in Bcl-2 expression and an increase in PARP cleavage. MASM also induced cell cycle arrest in G0/G1 phase, which was accompanied by increased p27 and decreased Cyclin D1 expression. Interestingly, MASM (2, 10, and 20 µmol/L) drastically reduced the EpCAM+/CD133+ cell numbers, suppressed the sphere formation, inhibited the expression of stem cell marker genes and promoted the expression of mature hepatocyte markers in the Hep3B and Huh7 spheroids. Additionally, MASM dose-dependently suppressed the PI3K/AKT/mTOR and AKT/GSK3ß/ß-catenin signaling pathways in Hep3B and Huh7 cells. In Huh7 xenograft bearing nude mice, MASM administration significantly inhibited Huh7 xenograft tumor growth and markedly reduced the number of surviving cancer stem-like cells in the tumors. MASM administration also reduced the expression of stem cell markers while increasing the expression of mature hepatocyte markers in the tumor tissues. The novel derivative of matrine, MASM, markedly suppresses HCC tumor growth through multiple mechanisms, and it may be a promising candidate drug for the treatment of hepatocellular carcinoma.

[Improving Agricultural Safety of Soils Contaminated with Polycyclic Aromatic Hydrocarbons by In Situ Bioremediation].

In order to reduce the risk of enrichment of polycyclic aromatic hydrocarbons (PAHs) in crops, reduce the potential hazards of food-sourced PAHs to human and increase the agricultural safety of PAHs contaminated soils, the bio-augmented removal of polycyclic aromatic hydrocarbons (PAHs) was investigated through in situ remediation by introducing Rhodobacter sphaeroides (RS) into the agricultural soil contaminated by PAHs. The 50-times diluted RS was sprayed on leaf surface (in area B) or irrigated to roots (in area D). The treatment of spraying water of the equal amount was taken as the control (A) and the wheat field without any treatment as the blank (CK). Treatments were conducted since wheat seeding. Soil and wheat samples were collected in the mature period to analyze the changes of community structure of the soil microorganisms and the concentration of PAHs in soils and investigate the strengthening and restoration effects of RS on PAHs contaminated soils. Compared to the CK Area, the areas B and D revealed that the variation ratio of phospholipid fatty acids (PLFAs) that were the biomarker of soil microorganisms was 29.6%, and the ratio of total PAHs removed was increased 1.59 times and 1.68 times, respectively. The dry weight of wheat grain of 50 spikes was increased by 8.95% and 12.5%, respectively, and the enrichment factor of total PAHs was decreased by 58.9% and 62.2% respectively in the wheat grains. All the results suggested that RS reduced enrichment of PAHs in wheat grains and increased wheat yield, which had great exploitation and utilization potentiality in repairing and improving the agricultural safety of the soils contaminated with PHAs.

[Running Condition and Bacterial Community Associated with the Partial Nitritation System].

In partial nitritation process, the sludge concentration was higher than 4000 mg x L(-1), DO was less than 0.2 mg x L(-1), the temperature of 15-29 degrees C, the reactor HRT of 4.6 h, and the circulation ratio was 75%, not only the microbial biomass reached the highest value but also the ratio of nitrite to ammonium of the effluent could be controlled at approximate 1.0 by adjusting the dissolved oxygen concentration. A quantitative PCR and the 16S rRNA genes clone library results demonstrated that ammonia-oxidizing bacteria were the dominant among nitrite-oxidizing bacteria at low dissolve oxygen concentration, that the bacteria promoted the running of the partial nitritation. Compared with conventional nitrification systems, in partial nitritation process, Nitrobacter and Nitrospira could not be detected among the system, and abundance of Planctomycetes was higher in partial nitritation process than that of conventional nitrification systems. Phylogenetic analysis of bacterial amoA gene sequences suggested that ammonia-oxidizing bacteria of the partial nitritation system was dominated by Nitrosomonas sequences, so partial nitritation is to be feasible technically and economically.

[Impact on the microbial community of municipal sewage in the anammox system during the cooling process].

Anaerobic ammonium oxidation is an important part of the biological nitrogen removal process, and the performance of the process is determined by the microbial community structure. Low-temperature anaerobic ammonium oxidation technology has good prospects for saving a lot of energy, and anaerobic ammonium oxidation bacteria play a vital role in the removal of total nitrogen from waste water. To explore the microbial community structure changes of anammox reactor in sewage treatment during the cooling process (from 30 degrees C to 20 degrees), the total amount of the microbial, the quantity of anaerobic ammonium oxidation and the change of functional microbial community were investigated in a sewage treatment process using the phospholipid fatty acid method (PLFA), quantitative PCR and the clone library of bacterial 16S rRNA. The PLFAs results showed that the total amount of microbial was first decreased and then gradually increased with the running time, when the temperature dropped from 30 degrees C to 20 degrees C, and the NH4+ -N content in the effluent of the system was decreased. The quantitative PCR results showed that 16S rRNA gene copies of anammox bacteria increased from 1.19 x 10(8) copies x mL(-1) to 1.86 x 10(8) copies x mL(-1) in the wastewater. The PCR-DGGE results showed that when the temperature decreased, the anammox bacteria were further enriched. A shift of anammox bacteria community from single Candidatus Kuenenia sp. to a combination of Candidatus Brocadia sp. and Candidatus Kuenenia sp. was observed.

[Influence of Mirabilis jalapa Linn. Growth on the Microbial Community and Petroleum Hydrocarbon Degradation in Petroleum Contaminated Saline-alkali Soil].

In order to explore the effect of Mirabilis jalapa Linn. growth on the structure characteristics of the microbial community and the degradation of petroleum hydrocarbon (TPH) in the petroleum-contaminated saline-alkali soil, Microbial biomass and species in the rhizosphere soils of Mirabilis jalapa Linn. in the contaminated saline soil were studied with the technology of phospholipid fatty acids (PLFAs) analysis. The results showed that comparing to CK soils without Mirabilis jalapa Linn., the ratio of PLFAs species varied were 71. 4%, 69. 2% and 33. 3% in the spring, summer and autumn season, respectively. In addition, there was distinct difference of the biomasses of the microbial community between the CK and rhizosphere soils and among the difference seasons of growth of Mirabilis jalapa Linn.. Compare to CK soil, the degradation rates of total petroleum hydrocarbon (TPH) was increased by 47. 6%, 28. 3%, and 18. 9% in spring, summer, and autumn rhizosphere soils, respectively. Correlation analysis was used to determine the correlation between TPH degradation and the soil microbial community. 77. 8% of the total soil microbial PLFAs species showed positive correlation to the TPH degradation (the correlation coefficient r > 0), among which, 55. 6% of PLFAs species showed high positive correlation(the correlation coefficient was r≥0. 8). In addition, the relative content of SAT and MONO had high correlation with TPH degradation in the CK sample soils, the corelation coefficient were 0. 92 and 0. 60 respectively; However, the percent of positive correlation was 42. 1% in the rhizosphere soils with 21. 1% of them had high positive correlation. The relative content of TBSAT, MONO and CYCLO had moderate or low correlation in rhizosphere soils, and the correlation coefficient were 0. 56, 0. 50, and 0. 07 respectively. Our study showed that the growth of mirabilis Mirabilis jalapa Linn. had a higher influence on the species and biomass of microbial community in the rhizosphere soils, and the results will provide a basis theory for the research of phytoremediation petroleum contaminated saline soil.

The impacts of different long-term fertilization regimes on the bioavailability of arsenic in soil: integrating chemical approach with Escherichia coli arsRp::luc-based biosensor.

An Escherichia coli arsRp::luc-based biosensor was constructed to measure the bioavailability of arsenic (As) in soil. In previous induction experiments, it produced a linear response (R (2) = 0.96, P < 0.01) to As from 0.05 to 5 µmol/L after a 2-h incubation. Then, both chemical sequential extraction, Community Bureau of Reference recommended sequential extraction procedures (BCR-SEPs) and E. coli biosensor, were employed to assess the impact of different long-term fertilization regimes containing N, NP, NPK, M (manure), and NPK + M treatments on the bioavailability of arsenic (As) in soil. Per the BCR-SEPs analysis, the application of M and M + NPK led to a significant (P < 0.01) increase of exchangeable As (2-7 times and 2-5 times, respectively) and reducible As (1.5-2.5 times and 1.5-2.3 times, respectively) compared with the no fertilization treated soil (CK). In addition, direct contact assay of E. coli biosensor with soil particles also supported that bioavailable As in manure-fertilized (M and M + NPK) soil was significantly higher (P < 0.01) than that in CK soil (7 and 9 times, respectively). Organic carbon may be the major factor governing the increase of bioavailable As. More significantly, E. coli biosensor-determined As was only 18.46-85.17 % of exchangeable As and 20.68-90.1 % of reducible As based on BCR-SEPs. In conclusion, NKP fertilization was recommended as a more suitable regime in As-polluted soil especially with high As concentration, and this E. coli arsRp::luc-based biosensor was a more realistic approach in assessing the bioavailability of As in soil since it would not overrate the risk of As to the environment.