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Community-based microbial source tracking (MST) can be used to determine fecal contamination from multiple sources in the aquatic environment. However, there is little scientific information on its application potential in water environmental management. Here, we compared SourceTracker and Fast Expectation-maximization Microbial Source Tracking (FEAST) performances on environmental water bodies exposed to low fecal pollution and evaluated treatment effects of fecal pollution in the watershed utilizing community-based MST. Our results showed that FEAST overall outperformed SourceTracker in sensitivity and stability, and was able to discern multi-source fecal contamination (mainly chicken feces) in ambient water bodies exposed to low fecal inputs. Consistent with our previous PCR/qPCR-based MST assays, FEAST analysis indicates that fecal pollution has been significantly mitigated through comprehensive environmental treatment by the local government. This study suggests that FEAST can be a powerful tool for accurately evaluating the contribution of multi-source fecal contamination in environmental water, facilitating environmental management.

Low quality and yield of methane severely hindered the industrial application of straw biogas fermentation and there has been no effective solution found so far. In this study, a novel method has been developed to improve the quality and yield of methane during biogas fermentation. We coupled microbial electrolysis cell (MEC) with normal anaerobic fermentation to enhance the yield and purity of methane. This novel fermentation process achieved the methane purity of more than 85%, which was critically higher than those of previously published reports. With the stimulation from microorganisms and electric current, the degradation of fiber has been greatly enhanced. The MEC system significantly improves the yield and purity of biogas, bringing a new path to synthesize the methane by the carbon dioxide and hydrogen ions in solution under the electron. Electrochemical index analysis showed the extra methane synthesis which was mainly led by the external circuit electron transfer. The result of the gas chromatograph and solid degradation rate showed that the carbon source of extra methane was CO2 produced in normal fermentation and extra volatile solid degradation. These results show that MEC significantly enhanced the quality and yield of methane in a straw fermentation process, giving insights for normal anaerobic fermentation.

The fusion of large group decision-making preferences is generally based on hard constraints, and the general low-consensus heterogeneous preference interaction situation of weak relationship decision-making under soft constraints has not been investigated. This study puts forward the preference connotation structure and preference attributes of the intertemporal decision-making of weak relationships groups, objective preference comparison standards between individuals, preference interaction neighborhoods between individuals, preference learning adjustment rules, and preference cycle interaction result evaluation connotations. On this basis, this research constructs a multistage and multiple-round intertemporal decision-making preference dynamic fusion theory and a method for weak relationship large groups. The simulation results verify and support the constructed preference fusion theory and method, indicating that a relatively rational interactive learning and adjustment process can improve the group decision-making performance of the key digital technology R&D team for offshore wind power project construction, operation, and maintenance and effectively improve the convergence level, convergence time, comprehensive decision-making benefits, and decision-making cognition. In the increasingly open large group intertemporal decision-making situation, these research viewpoints and conclusions will help to expand the strong relationship hypotheses of preference fusion in previous group decision-making research. The research opinions and conclusions supplement the theory and method of preference interaction fusion under soft constraints in large group decision-making.

Innovative education is a higher training requirement for education in the period of social transformation. It needs the education to cultivate talents with innovative consciousness and ability for the development of society. High school is critical for facilitating students’ innovative consciousness, innovative thinking, and innovative ability development. Aiming at the problems of insufficient resources, fragmentation of education, and simplification of evaluation in the current practice of innovative education, Zhengzhou No.12 Middle School integrates the characteristics of maker education and STEAM education to carry out the top-level selection, training, evaluation, and development of innovative talents. Formed an innovative education curriculum system that takes “Workshop + Project” as the starting point, relies on research learning courses, multi-dimensional evaluation as a guarantee, and integrates classroom teaching, club activities, project research, intellectual property rights, and expert guidance.

The relationships among the production of methane, the physicochemical properties of coal, and the composition of microbial communities are poorly understood in methanogenic bioconversion. In this study, we investigated the changes in microbial communities during the methanogenic process of coal based on culture-dependent methods as well as the physicochemical properties of the coal samples. The process of methane production could be clearly divided into four phases (lag, log, peak, and stationary phases). The initial bacterial communities in the cultivation were predominantly Bacteroidales, Actionmycetales, and Bacillales; the archaeal community was present at values below the detection limit. However, distinct changes in bacterial communities were noted at the log phase of methane production. Bacteroides species accounted for >80% of the total bacterial community, and acetotrophic Methanosarcina was the only archaeal community. Interestingly, Clostridiales increased considerably during the first 2 weeks, but decreased thereafter, indicating that Clostridiales may play a unique role during the initial stage of methanogenic coal bioconversion. Furthermore, the final coal sample showed decreased C and O contents and increased N and H contents. Volatile and ash contents as well as microporosity were also higher than those in the initial state. These results suggested that methanogenic coal bioconversion was a complex biochemical process and that the physicochemical properties of coal were altered in methanogenic bioconversion. Moreover, these findings may facilitate the development of strategies to improve the production of biomethane utilizing coal.

The overall reform experiment of elementary and middle school education is a reform exploration that touches the whole process of education. Horizontally, it includes various educational factors within the school and vertically includes multiple educational stages. This experiment is based on the overall idea, from the beginning of the experiment in some areas to the whole of China, and systematically designs and comprehensively reforms the various factors that constitute school education at multiple stages. Starting from the background of the overall reform experiment, this paper elaborates on the experiment’s content, history, and impact to objectively and truthfully summarize the experiment, inspire most educators, and explore practical methods for improving the experiment quality education.

Biogenic methane in shallow shale reservoirs has been proven to contribute to economic recovery of unconventional natural gas. However, whether the microbes inhabiting the deeper shale reservoirs at an average depth of 4.1 km and even co-occurring with sulfate-reducing prokaryote (SRP) have the potential to produce biomethane is still unclear. Stable isotopic technique with culture-dependent and independent approaches were employed to investigate the microbial and functional diversity related to methanogenic pathways and explore the relationship between SRP and methanogens in the shales in the Sichuan Basin, China. Although stable isotopic ratios of the gas implied a thermogenic origin for methane, the decreased trend of stable carbon and hydrogen isotope value provided clues for increasing microbial activities along with sustained gas production in these wells. These deep shale-gas wells harbored high abundance of methanogens (17.2%) with ability of utilizing various substrates for methanogenesis, which co-existed with SRP (6.7%). All genes required for performing methylotrophic, hydrogenotrophic and acetoclastic methanogenesis were present. Methane production experiments of produced water, with and without additional available substrates for methanogens, further confirmed biomethane production via all three methanogenic pathways. Statistical analysis and incubation tests revealed the partnership between SRP and methanogens under in situ sulfate concentration (~ 9 mg/L). These results suggest that biomethane could be produced with more flexible stimulation strategies for unconventional natural gas recovery even at the higher depths and at the presence of SRP.

Ternary liquid–liquid equilibria (LLE) data for water + furfural + cyclopentyl methyl ether (CPME) and quaternary LLE data for water + furfural + acetic acid + CPME were measured at T = 293.15, 303...

Microbial communities of sludge samples from a full-scale anaerobic digestion (AD) fed with primary sludge (PS) and excess sludge (ES) were analyzed using qPCR and MiSeq. The results showed that the microbial composition of digested sludge remained relatively stable but was partially changed by microbial immigration from feeding sludge. The dominant archaea in the digested sludge were largely the same as those in the feeding sludge, but their abundances differed markedly. The dominant fungal genera in the digested sludge were different from those in PS but were similar to those in ES. Various differences in bacterial community differences between digested sludge and PS/ES were observed. Notably, this study is the first to suggest Verrucomicrobia is the predominant bacterial phylum in the digested sludge, and that numerous unreported microorganisms belonging to the order LD1-PB3 existed in this AD system and potentially played roles in the processes of hydrolysis, fermentation, and acetogenesis.

The difficult degradation of fermentation substrate is the problem that restricts the anaerobic digestion (AD) of spent mushroom substrate (SMS). To obtain a potential and efficient solution to improve poor stability and low reactor efficiency, this study investigated the synergistic effect of biochar + Ce3+ on AD of SMS under the condition of composting pretreatment (CP). The gas production results showed that CP shortened the lag phase of reaction, and then biochar + Ce3+ synergistically enhanced CH4 production. The cumulative CH4 yield of the biochar + Ce3+ group reached 69.69 L/kgVS, which was 22.3% and 16.2% higher than that of a non-CP with no additions group and a CP with no additions group, respectively. The high-throughput sequencing analysis revealed that CP increased bacterial richness and diversity, and the co-addition of biochar + Ce3+ was beneficial to the growth of Syntrophomonadaceae, Anaerolineaceae and Ruminococcaceae species. Hence, following composting pretreatment (CP), biochar and Ce3+ worked synergistically to increase CH4 production. This indicated that our proposed method improved the process efficiency of CH4 production from SMS fermentation.

Microorganisms present in production facilities of shale gas can cause substantial increases in production costs and complicate water management. Here, an uncommon microbial distribution was observed at six gas-gathering stations of deep shale wells (average depth: 4162 m) in the Sichuan Basin, China. Employing Illumina MiSeq 16S rRNA gene sequencing and quantitative polymerase chain reaction (qPCR), the majority of bacterial communities in gas–water separators and water storage tanks sampled belonged to the genus Shewanella (accounting for 60.67% of total bacterial sequences detected) as well as Marinobacter, Marinobacterium, Arcobacter, Acetobacterium, and Alkalibacter that were encountered in previously reported shale produced water. Archaea were mainly methylotrophic and halotolerant methanogenic genera, including Methanolobus, Methanohalophilus, and Methanocalculus. For the first time, fungi (primarily Ascomycota and Basidiomycota) were detected in the produced water from production facilities, and some genera, such as Cladosporium, may be associated with corrosion. Apart from Shewanella, other sulfidogenic taxa mainly belonging to Dethiosulfovibrio and Dethiosulfatibacter and acid producers belonging to Acetobacterium were also encountered. Microbial communities in storage tanks were more abundant and diverse than those in separators. Notably, detection of biocorrosive sulfate-reducing bacteria (SRB) increased from separators (0.39%) to storage tanks (2.37%). This study expands our knowledge about microbial diversity in production facilities of shale gas and the findings may have implications in guiding wastewater management during shale gas production.

The solid-state fermentation state of Chinese Maotai liquor involves the interaction of several complex microbial communities leading to the generation of the most complex liquor fermentation system in the world and contributes to the unique flavor and aroma of the liquor. In this study, total DNA was extracted from 3 fermented grain samples (FG1, FG2, and FG3) and 12 environmental samples, including Daqu (DA1, DA2, DA3, and DA4), cellar mud (CS1, CS2, and CS3), soil (SL1 and SL2), air (A1 and A2), and sorghum (SH), and the 16S and 18S rRNA genes were amplified. The distribution of typical microorganisms in the samples was analyzed using nested PCR-denaturing gradient gel electrophoresis, while quantitative PCR amplification of 16S rRNA and internal transcribed spacer genes was performed to estimate the microbial abundance present in each sample. The results indicated that Daqu was the primary source of bacteria, followed by the air, soil, and sorghum samples, while the majority of the fungi responsible for Maotai liquor fermentation were from Daqu and sorghum. Highest bacterial concentrations were found in fermented grains, followed by Daqu and sorghum, while the highest fungal concentrations were found in Daqu, followed by sorghum and an air sample from outside the liquor production area. The findings of this study may provide information regarding the mechanisms responsible for flavor development in Maotai liquor, and may be used to further optimize the traditional art of making liquor.

Background Toxic compounds present in both the hydrolysate and pyrolysate of lignocellulosic biomass severely hinder the further conversion of lignocellulose-derived fermentable sugars into useful chemicals by common biocatalysts like Zymomonas mobilis, which has remarkable advantages over yeast. Although the extra detoxification treatment prior to fermentation process can help biocatalysts to eliminate the inhibitory environment, it is not environment friendly and cost effective for industrial application. As also reported by previous studies, an ideal and holistic approach to solve this issue is to develop microbial strains with inhibitor tolerance. However, previously engineered strains had the limitation that they could not cope well with the synergistic effect of multiple inhibitors as they are resistant only to a single inhibitor. Hence, understanding the universal cellular responses of Z. mobilis to various inhibitors may guide the designing of rational strategies to obtain more robust engineered strains for biofuel production from lignocellulosic biomass. Results Quantitative proteomics and metabolomics approaches were used to determine the cellular responses of Z. mobilis ZM4 to representative biomass-derived inhibitors like formic acid, acetic acid, furfural, 5-hydroxymethylfurfural, and phenol. The differentially expressed proteins identified under the challenge of single and combined inhibitors were involved in cell wall/membrane biogenesis, energy production, DNA replication, DNA recombination, DNA repair, DNA transcription, RNA translation, posttranslational modification, biosynthesis of amino acids, central carbon metabolism, etc. Metabolomics analysis showed that the up- or down-regulation pattern of metabolites was changed consistently with that of relevant proteins. Conclusion Fifteen up-regulated proteins (e.g., Isopropylmalate isomerase LeuC, transcription-repair-coupling factor Mfd, and phosphoglucose isomerase PGI) and thirteen down-regulated proteins (e.g., TonB-dependent transporter ZMO1522, transcription termination factor Rho, and S1/P1 nuclease ZMO0127) were identified as candidate proteins related to all the stress conditions, implying that these proteins are potential biomarkers for the improvement of Z. mobilis ZM4 to resist complex biomass-derived inhibitors. These data can be used to generate a database of inhibitor-tolerance biomarkers, which could provide a basis for engineering Z. mobilis that would be able to grow in the presence of multiple inhibitors and directly ferment the biomass-derived sugars into biofuels. Electronic supplementary material The online version of this article (10.1186/s13068-018-1287-5) contains supplementary material, which is available to authorized users.

Transgenic Bt cotton is widely cultivated, yet its impact on the phyllosphere mycobiome is poorly understood. Hence, the objective of this study was to investigate the effects resulting from the planting of Bt cotton on fungal diversity composition. The α diversity for the Bt cotton line SGK321 was lower than that of control plants at the budding stage and the blossoming and boll-forming stage, while an obvious increase in diversity for Bt cotton XP188 was observed at the same stage. The Cry1Ac levels were higher at the seedling stage than at the budding stage and the blossoming and boll-forming stage. There was no direct relationship between the expression of the Bt protein and variation in the fungal community for Bt cotton. However, PCoA and PCA results indicated that community structure differed among developmental stages. These results indicated that developmental stage rather than Cry1Ac expression was the key factor shaping the phyllosphere mycobiome in transgenic cotton.

This study evaluated the effects of the inocula from natural wetland, lab-scale and full-scale anaerobic reactors on wheat straw anaerobic digestion. Three replicate batch reactors were constructed for each inoculum to investigate the reactor performances and microbial communities. Reactors seeded with full-scale reactor samples were started up most rapidly, achieved the highest methane production, and were recognized as the higher efficient reactors. The dominance of acetoclastic methanogens, including Methanosaeta and Methanoscrina, was crucial for the higher efficient reactors, whereas hydrogenotrophic methanogens were dominant in other reactors. Genus Treponema, which could enhance the cellulose degradation and conduct homoacetogenesis, was first reported to be dominant in the bacterial communities of high efficient reactors. Inoculum sources and process conditions were suggested to be the deterministic factors in shaping the microbial communities in the higher efficient reactors. These findings contribute to the startup of new anaerobic reactors.

Additional file 1: Text S1. Distribution of gene ontology categories and KEGG pathways of the differential expression proteins and metabolites. Fig. S1 OD values of the cell cultures under different concentrations of inhibitors. Fig. S2 Cell growth, residual glucose, and ethanol production of the cell cultures under different concentrations of inhibitors. Fig. S3 Numbers of differential expression proteins in the groups treated by different inhibitors. Fig. S4 PCA analysis of the total metabolites identified in the inhibitor-treated groups and control. Fig. S5 Metabolic pathways and Gene Ontology categories that the differentially expressed proteins were mainly involved in. Fig. S6 Documented interactions based on String 9.05 database for the differentially expressed proteins shared by all the inhibitor conditions.

Mining of ore body in the vicinity of a shaft has a significant influence on its stability. The in situ monitoring and numerical simulation are employed to analyze the effect of shaft pillar extraction at Xincheng Gold Mine. The XI# ore body is recently found around and beneath the shaft, and mining in this area may be detrimental to the shaft. Firstly, on the base of geological survey and in situ displacement monitoring, mechanical parameters of rock mass are obtained and the displacement around the shaft is measured. Secondly, the sensitivities of five main factors that may affect the shaft displacement are analyzed by means of orthogonal experiment according to the numerical simulation with FLAC3D. Finally, a numerical model is established according to the in situ condition; in order to forecast the shaft displacement induced by mining activities of XI# orebody, the Mining Priority Index (MPI) is put forward and used to select the optimal mining sequence. Based on the comparison between the numerical results with the monitoring data, it is determined that the ore within 100 m from the shaft is not suggested to be extracted until the last period of the shaft life.

Bio-foaming is a major problem in solid separation in activated sludge (AS) wastewater treatment systems. Understanding the changes in bacterial communities during sludge foaming is vital for explaining foam formation. Changes in bacterial communities in the foam, corresponding foaming AS, and non-foaming AS in a seasonal foaming wastewater treatment plant (WWTP) in Northern China were investigated by high-throughput pyrosequencing and molecular quantification-based approaches. We found that bacterial communities of the foam and the corresponding foaming AS were similar but markedly different from those of the non-foaming AS. Actinobacteria was the predominant phylum in the foam and the corresponding foaming AS, whereas Proteobacteria was predominant in the non-foaming AS. Similar to the results of most previous studies, our results showed that Candidatus "Microthrix parvicella" was the predominant filamentous bacteria in the foam and the corresponding foaming AS and was significantly enriched in the foam compared to the corresponding foaming AS. Its abundance decreased gradually with a slow disappearance of sludge foaming, indicating that its overgrowth had a direct relationship with sludge foaming. In addition to Candidatus M. parvicella, Tetrasphaera and Trichococcus might play a role in sludge foaming, because they supported the changes in AS microbial ecology for foam formation. The effluent water quality of the surveyed plant remained stable during the period of sludge foaming, but the microbial consortia responsible for nitrogen and phosphorus transformation and removal markedly changed compared to that in the non-foaming AS. This study adds to the previous understanding of bacterial communities causing foaming in WWTPs.

Extraction followed by heteroazeotropic distillation is considered to be a potentially energy-saving method for purifying acrylic acid. Based on our previous work, cyclopentyl methyl ether is an excellent solvent that can be used as extractive an agent as well as an entrainer. In this work, liquid–liquid equilibria (LLE) data of the quaternary system {water (1) + acrylic acid (2) + acetic acid (3) + cyclopentyl methyl ether (4)} were determined at T = (293.15, 303.15, and 313.15) K and p = 100.25 kPa. The reliability of the experimental data was evaluated using the Othmer–Tobias and Hand equations. The NRLT and UNIQUAC activity coefficient models were used to correlate the LLE data of the quaternary system. The UNIFAC-Dortmund model was used to predict the observed LLE data with a average root-mean-square deviation value of 3.41%. Additionally, the physical properties and extraction capabilities of cyclopentyl methyl ether, cyclohexane, and toluene were compared.

Microbial communities associated with biogenic coalbed methane (CBM) have been investigated extensively by sampling produced water and coal samples. However, little is known about the microbial communities associated with CBM gas. In this study, we employed pyrosequencing and real-time polymerase chain reaction to investigate the microbial communities in CBM gas from a CBM field associated with Ordos Basin in China, where biogenic CBM had been identified and methanogens and related bacteria had been found to be present in coal and produced water samples. The pyrosequencing results revealed that the GOM_Arc_I group, with 99.3% archaeal sequence reads, was the predominant archaea in gas samples. The main bacteria present in gas samples were Proteobacteria. In particular, the genus Herbaspirillum comprised approximately 76% of bacterial sequences. Most of the detected bacteria had the potential to degrade aromatic and cellulose-derived compounds in coal and promote nitrogen cycling in coalbeds. The microbial diversity in gas was lower than that in coal and produced water, and significant differences were observed in the microbial communities in gas. These results provided insights into the archaeal and bacterial communities associated with CBM gas at this location and may improve our understanding of the current status of archaeal and bacterial communities in CBM fields.

1,6-Anhydro-N-acetylmuramic acid kinase (AnmK) is the unique enzyme that marks the recycling of the cell wall of Escherichia coli. Here, 81 fungal AnmK-like kinase sequences from 57 fungal species were searched in the NCBI database and a phylogenetic tree was constructed. The three-dimensional structure of an AnmK-like kinase, levoglucosan kinase (LGK) of the yeast Lipomyces starkeyi, was modeled; molecular docking revealed that AnmK and LGK are conserved proteins, and 187Asp, 212Asp are enzymatic residues, respectively. Analysis suggests that 1,6-anhydro-N-acetylglucosamine (anhGlcNAc) and/or 1,6-anhydro-β-d-glucosamine (anhGlcN) would be the appropriate substrates of AnmK-like kinases. Also, the counterparts of other characteristic enzymes of cell wall recycling of bacteria were found in fungi. Taken together, it is proposed that a putative recycling of anhGlcNAc/anhGlcN, which is associated with the hydrolysis of cell walls, exists in fungi. This computational analysis will provide new insights into the metabolism of fungal cell walls.

Microbial diversity and abundance in bioaerosols of a coal mine were analyzed based on 454 pyrosequencing and real-time polymerase chain reaction (PCR). A total of 37,191 high quality sequences were obtained and could be classified into 531, 1730 and 448 operational taxonomic units respectively for archaea, bacteria and fungi at 97% sequence similarity. The Shannon diversity index for archaea, bacteria and fungi was respectively 4.71, 6.29 and 3.86, indicating a high diversity in coal mine bioaerosols. Crenarchaeota, Proteobacteria and Ascomycota were the dominant phyla for archaea, bacteria and fungi, respectively. The concentrations of total archaea, bacteria and fungi were 1.44×10(8), 1.02×10(8) and 9.60×10(4) cells/m3, respectively. Methanotrophs observed in bioaerosols suggested possible methane oxidation in the coal mine. The identified potential pathogens to coal miners, such as Acinetobacter schindleri, Aeromonas cavernicola, Alternaria alternata, Aspergillus penicillioides, Cladosporium cladosporioides, and Penicillium brevicompactum were also observed. This was the first investigation of microbial diversity and abundance in coal mine bioaerosols. The investigation of microbial communities would be favorable in promoting the progress of methane control based on microbial technique and concern on coal miners' health.

Extraction followed by heterogeneous azeotropic distillation is an effective and energy-saving method to separate acrylic acid from aqueous solution. In this work, the liquid–liquid equilibria data for the system of water + acrylic acid + cyclopentyl methyl ether at three temperatures were determined at 100.249 kPa. The reliability of the liquid–liquid equilibria data was ascertained by using Hand and Othmer–Tobias correlations. The separation factors of cyclopentyl methyl ether at different temperatures were compared. NRTL and UNIQUAC models were used to correlate the liquid–liquid equilibria experimental data. Moreover, a comparative study on the three solvents, including cyclopentyl methyl ether, isobutyl ethanoate, and 4-methyl-2-pentanone, was made in terms of basic physical properties and extraction ability.

Pyrolysate from waste cotton was acid hydrolyzed and detoxified to yield pyrolytic sugars, which were fermented to ethanol by the strain Escherichia coli ACCC 11177. Mathematical models based on the fermentation data were also constructed. Pyrolysate containing an initial levoglucosan concentration of 146.34 g/L gave a glucose yield of 150 % after hydrolysis, suggesting that other compounds were hydrolyzed to glucose as well. Ethyl acetate-based extraction of bacterial growth inhibitors with an ethyl acetate/hydrolysate ratio of 1:0.5 enabled hydrolysate fermentation by E. coli ACCC 11177, without a standard absorption treatment. Batch processing in a fermenter exhibited a maximum ethanol yield and productivity of 0.41 g/g and 0.93 g/L·h−1, respectively. The cell growth rate (r x ) was consistent with a logistic equation $$ {r}_x=0.21\left(1-\frac{X}{3.75}\right)X $$ , which was determined as a function of cell growth (X). Glucose consumption rate (r s ) and ethanol formation rate (r p ) were accurately validated by the equations $$ {r}_s=0.25\frac{dX}{dt}+0.47X $$ and $$ {r}_p=0.05\frac{dX}{dt}+0.29X $$ , respectively. Together, our results suggest that combining mathematical models with fermenter fermentation processes can enable optimized ethanol production from cellulosic pyrolysate with E. coli. Similar approaches may facilitate the production of other commercially important organic substances.

Wastewater contains numerous viruses. In this study, picobirnaviruses (PBVs) were detected in the stream of a wastewater treatment plant in Changsha, Hunan province, China, and evolutionary analysis of the isolated PBVs was performed. The phylogenetic tree revealed that the PBVs were highly divergent and could be classified into six distinct groups according to their hosts. Among these groups, pairwise comparison of the six groups revealed that the nucleotide distance of group 4 (bootstrap value = 0.92; nucleotide identity = 94%) was the largest. Thus, group 4 might represent a new division of PBVs. Comprehensive analysis of the obtained PBV sequences to investigate their evolutionary history and phylodynamics revealed that group 5 (PBVs from monkey) exhibited maximum polymorphism (K = 30.582, S = 74, η = 98, Pa = 47) and lowest nucleotide substitutions per site per year (6.54E-3 subs per site per year), except group 4. Maximum clade credibility tree indicated that group 5 appeared earlier than the other groups. In conclusion, this study detected PBVs in treated wastewater in China, and identified a new PBV group. Furthermore, among these PBVs, group 5 was found to survive longer and present a balance between PBVs and their monkey host.

China has been the forerunner of large-scale membrane bioreactor (MBR) application. Since the first large-scale MBR (⩾ 10 000 m3·d−1) was put into operation in 2006, the engineering implementation of MBR in China has attained tremendous development. This paper outlines the commercial application of MBR since 2006 and provides a variety of engineering statistical data, covering the fields of municipal wastewater, industrial wastewater, and polluted surface water treatment. The total treatment capacity of MBRs reached 1 × 106 m3·d−1 in 2010, and has currently exceeded 4.5 × 106 m3·d−1 with ∼75% of which pertaining to municipal wastewater treatment. The anaerobic/anoxic/aerobic-MBR and its derivative processes have been the most popular in the large-scale municipal application, with the process features and typical ranges of parameters also presented in this paper. For the treatment of various types of industrial wastewater, the configurations of the MBR-based processes are delineated with representative engineering cases. In view of the significance of the cost issue, statistics of capital and operating costs are also provided, including cost structure and energy composition. With continuous stimulation from the environmental stress, political propulsion, and market demand in China, the total treatment capacity is expected to reach 7.5 × 106 m3·d−1 by 2015 and a further expansion of the market is foreseeable in the next five years. However, MBR application is facing several challenges, such as the relatively high energy consumption. Judging MBR features and seeking suitable application areas should be of importance for the long-term development of this technology.

The microbial community compositions and potential ammonia oxidation in the topsoil at different positions of sand dune (stoss slope, crest, lee slope, and interdune) from the Gurbantunggut Desert, the largest semi-fixed desert in China, were investigated using several molecular methods. Actinobacteria and Proteobacteria (especially Alphaproteobacteria) were commonly the dominant taxa across all soil samples. Bacterial communities were similar in soils collected from the stoss slopes and interdunes (HC-BSCs, biological soil crusts with a high abundance of cyanobacteria), containing more abundant cyanobacterial populations (16.9-24.5%) than those (0.2-0.7% of Cyanobacteria) in the crests and lee slopes (LC-BSCs, biological soil crusts with a low abundance of cyanobacteria). The Cyanobacteria were mainly composed of Microcoleus spp., and quantitative PCR analysis revealed that 16S rRNA gene copy numbers of Cyanobacteria (especially genus Microcoleus) were at least two orders of magnitude higher in HC-BSCs than in LC-BSCs. Heterotrophic Geodermatophilus spp. frequently occurred in HC-BSCs (2.5-8.0%), whereas genera Arthrobacter, Bacillus, and Segetibacter were significantly abundant in LC-BSC communities. By comparison, the desert archaeal communities were less complex, and were dominated by Nitrososphaera spp. The amoA gene abundance of ammonia-oxidizing archaea (AOA) was higher than that of ammonia-oxidizing bacteria (AOB) in all soil samples, particularly in the interdunal soils (10(6)-10(8) archaeal amoA gene copies per gram dry soil), indicating that AOA possibly dominate the ammonia oxidation at the interdunes.

Permafrost wetlands are important methane emission sources and fragile ecosystems sensitive to climate change. Presently, there remains a lack of knowledge regarding bacterial communities, especially methanotrophs in vast areas of permafrost on the Tibetan Plateau in Northwest China and the Sanjiang Plain (SJ) in Northeast China. In this study, 16S rRNA-based quantitative PCR (qPCR) and 454 pyrosequencing were used to identify bacterial communities in soils sampled from a littoral wetland of Lake Namco on the Tibetan Plateau (NMC) and an alluvial wetland on the SJ. Additionally, methanotroph-specific primers targeting particulate methane monooxygenase subunit A gene (pmoA) were used for qPCR and pyrosequencing analysis of methanotrophic community structure in NMC soils. qPCR analysis revealed the presence of 10(10) 16S rRNA gene copies per gram of wet soil in both wetlands, with 10(8) pmoA copies per gram of wet soil in NMC. The two permafrost wetlands showed similar bacterial community compositions, which differed from those reported in other cold environments. Proteobacteria, Actinobacteria , and Chloroflexi were the most abundant phyla in both wetlands, whereas Acidobacteria was prevalent in the acidic wetland SJ only. These four phyla constituted more than 80 % of total bacterial community diversity in permafrost wetland soils, and Methylobacter of type I methanotrophs was overwhelmingly dominant in NMC soils. This study is the first major bacterial sequencing effort of permafrost in the NMC and SJ wetlands, which provides fundamental data for further studies of microbial function in extreme ecosystems under climate change scenarios.

A Gram-negative strain (TJ) capable of growing aerobically on mixed phthalate esters (PAEs) as the sole carbon and energy source was isolated from the Haihe estuary, Tianjin, China. It was identified as belonging to the Sphingobium genus on the basis of morphological and physiological characteristics and 16S rRNA and gyrb gene sequencing. The batch tests for biodegradation of di-n-butyl phthalate (DBP) by the Sphingobium sp. TJ showed that the optimum conditions were 30 °C, pH 7.0, and the absence of NaCl. Stain TJ could tolerate up to 4% NaCl in minimal salt medium supplemented with DBP, although the DBP degradation rates slowed as NaCl concentration increased. In addition, substrate tests showed that strain TJ could utilize shorter side-chained PAEs, such as dimethyl phthalate and diethyl phthalate, but could not metabolize long-chained PAEs, such as di-n-octyl phthalate, diisooctyl phthalate, and di-(2-ethyl-hexyl) phthalate. To our knowledge, this is the first report on the biodegradation characteristics of DBP by a member of the Sphingobium genus.

Summary Both culture-dependent method and molecular technique were firstly used to simultaneously investigate the cultivable bacterial diversity and amylase production in three typical Daqus of Chinese spirits. The results showed that both cultivable bacterial diversity and amylase production were obviously different. The species of nine bacteria from Deshan, nine from Baisha and six from Wuling Daqus were identified. The total bacterial strains of 17, 15 and 14, and 9, 16 and 10 could produce α-amylase and glucoamylase, respectively, from the Daqus, and the enzyme yields were different. Bacillus licheniformis, Bacillus subtilis and Bacillus amyloliquefaciens not only were dominant bacteria in the Daqus, but also possessed high activities of α-amylase and glucoamylase. By comparison, Bacillus cereus and Bacillus oleronius were found to be another predominant bacterial species and good producers of α-amylase and glucoamylase in Deshan and Wuling Daqus, respectively.

Coal mine methane (CMM) is gaining global attention, and especially, its biogenic methane regeneration is of increasing interest in recent years. Microbial communities in coal and water in a representative small-production coal mine of central China were surveyed by cultivation-independent methods. A total of 22 330 and 53 622 high-quality sequences were obtained for archaea and bacteria, respectively, by 454 pyrosequencing. Diversity indices Chao1, ACE, and Shannon (H′) for microbes in mine water were higher than those in coal. The methane-producing archaea Methanosaeta and Methanosarcina were the dominated communities observed in coal and mine water, respectively. A variety of anaerobic fermentative bacteria were identified, and the most abundant genera in coal and mine water were Rheinheimera and Hydrogenophaga, respectively. On the basis of the results of real-time polymerase chain reaction (PCR), microbial abundance in coal was 3.29 × 105 and 8.56 × 104 cells g–1 for archaea and bacteria, respectivel...

Tubular furnace pyrolysis reactor for the production of organic liquids from biomass has been demonstrated at a pilot-scale of 500 g/batch of dry feed at a temperature of 360-420 degrees C. Treatment of starch gives high yields of 1,6-anhydro-beta-D-glucopyranose (levoglucosan, LG). The yield depends on the heater temperature and the vacuum pressure in the reactor. The maximum yield of levoglucosan from corn starch is about 56% (analytical value) at ultimate pressure of 6 x 10(-2) Pa, pumping speed of 15 L/s and temperature of 390 degrees C. Under the same conditions, the products of levoglucosan pyrolysis are exactly the same as starch pyrolysis. Based on these experimental results and further thermal analysis, a new pyrolysis mechanism is provided and discussed. (c) 2013 Elsevier B.V. All rights reserved.

Biomass burning, a form of disturbance in soil ecosystem, is frequently carried out in farmland after harvest in China, which has potential influence on soil biological properties. To study the short-term effects of biomass burning on soil ammonia-oxidizing bacteria (AOB) and archaea (AOA), a field investigation utilizing poplar branch (PB) and corn stalk (CS) as feedstock for experimental biomass burning was conducted in farmland in Yanqing County, Beijing, China (116°12'E, 40°25'N). The shifts in abundance and community composition of AOB and AOA were investigated utilizing real-time polymerase chain reaction (PCR), cloning and sequencing approaches based on amoA genes. Striking increase in potential ammonia oxidation rate and abundance of soil AOA and AOB after fire were observed, as well as community composition of AOA. For AOB, little changes in diversity but significant shifts in relative abundance of different Clusters were observed after fire. Phylogenetic analyses of the amoA gene fragments showed that all AOB clones from different treatments were affiliated with Nitrosospira species and grouped into 5 clusters (3a, 3b, 3c, A and B). Most of the clones were almost evenly distributed in Cluster 3a, 3b, A and B before burning. However, domination in the clones by Cluster 3a was observed after fire. All AOA clones fell within Soil cluster (soil origin). Although Group 1.1b was found dominant in the obtained AOA clones in all the treatments, the relative abundance of clones belonging to Group 1.1b decreased after fire. These findings could be fundamental to improve our understanding of the effect of biomass burning on soil AOB and AOA in agricultural ecosystems. Key words: Biomass burning, soil ammonia-oxidizing bacteria, soil ammonia-oxidizing archaea, ammonia oxidation.

A Gram-negative, strictly aerobic, non-motile and non-spore-forming rod that produced white, viscous colonies, designated QHT, was isolated from bulking sludge collected from a municipal wastewater treatment plant in Beijing, China. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain QHT belonged to the genus Terrimonas and shared 96.3 % sequence similarity with Terrimonas lutea DYT, 94.1 % with Terrimonas ferruginea ATCC 13524T and 93.8 % with Terrimonas aquatica RIB1-6T. Strain QHT contained iso-C15 : 0, summed feature 3 (comprising one or more of C16 : 1ω7c, C16 : 1ω6c and iso-C15 : 0 2-OH) and iso-C15 : 1 G as the predominant fatty acids. The predominant polar lipid of strain QHT and members of the genus Terrimonas was phosphatidylethanolamine. The major isoprenoid quinone of strain QHT was MK-7 and the DNA G+C content was 41.0 mol%. DNA–DNA relatedness between strain QHT and T. lutea BCRC 17944T, T. ferruginea BCRC 17943T and T. aquatica BCRC 17941T was 32, 23 and 22 %, respectively. On the basis of phylogenetic inference, differential phenotypic data and low DNA–DNA relatedness with members of the genus Terrimonas , strain QHT represents a novel species, for which the name Terrimonas pekingensis sp. nov. is proposed. The type strain is QHT ( = CICC 10452T = NCCB 100397T). The descriptions of the genus Terrimonas and T. ferruginea , T. lutea and T. aquatica are also emended.

Systemic study on thermal dilute-acid hydrolysis of cotton straw has been conducted. The process of sequential two-step reaction has been established, which can greatly improve the utilization efficiency of lignocellulosic biomass. The hydrolyses were carried out in an 1 L erlenmeyer flask placed in the pressure steam sterilizer, where the hydrolysis retention time (0–60 min), liquid to solid ratio (8–14:1) and acid concentration (0–1 mol/L) were examined for the first stage. Optimization of first stage hydrolysis is desirable to achieve the highest yield of the sugars from hemicellulose and also as a pretreatment for the second acid hydrolysis. The solid residuals were further dilute-acid (0.2 mol/L) hydrolyzed in this study. This second-stage hydrolysis mainly completed the conversion of cellulose to levulinic acid and formic acid. At last, dilute-acid conversion of cotton straw to sugars (in the first stage), levulinic acid and formic acid (in the second stage) was completed.

Intertidal mangrove wetlands are of great economic and ecological importance. The regular influence of tides has led to the microbial communities in these wetlands differing significantly from those in other habitats. In this study, we investigated the microbiomes of the two largest mangrove wetlands in Hainan Island, China, which have different levels of anthropogenic protection. Soil samples were collected from the root zone of 13 mangrove species. The microbial composition, including key functional groups, was assessed using Illumina sequencing. Bioinformatics analysis showed that there was a significant difference in the microbiomes between the protected Bamen Bay and the unprotected Dongzhai Bay. The overall microbiome was assigned into 78 phyla and Proteobacteria was the most abundant phylum at both sites. In the protected wetland, there were fewer marine-related microbial communities, such as sulfate-reducing bacteria, and more terrestrial-related communities, such as Verrucomicrobia methanotrophs. We also observed distinct microbial compositions among the different mangrove species at the protected site. Our data suggest that the different microbiomes of the two mangrove wetlands are the result of a complex interaction of the different environmental variables at the two sites.