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Objective The study is aiming to explore the key corrosion bacteria in the production process of shale gas, and analyze the potential succession law of bacteria. Methods The 16S rRNA high-throughput sequencing analysis technology was used to sequence the bacterial flora in the fracturing fluid preparation water and produced water of a shale gas platform in Weiyuan area. Results The bacterial structure of fresh water is completely different from that of produced water and recycled flowback fluid, the richness and diversity of bacteria decreased after fracturing. The key corrosive bacteria include Arcobacter, Marinobacterium and Pseudomonas, etc. The bacterial community in the freash water is mainly composed of mesophilic, aerobic bacteria with weak functions such as sulfate reduction and acid production. While in the recycled flowback fluid, there are a large number of bacteria with functions of sulfur metabolism, acid production and biofilm production. After fracturing, in the produced water there are mainly facultative anaerobic, anaerobic or strictly anaerobic bacteria with functions such as sulfate reduction, sulfur reduction, sulfur oxidation, acid production, biofilm production, iron reduction, and some thermophilic bacteria were identified. Conclusion This provides theoretical and technical support for further research on bacterial corrosion of gathering and transportation pipelines and pipeline protection. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The experiment was to isolate and identify cellulose-degrading anaerobic bacteria from the cecum of horses. The samples were collected from horse cecum in Yili, Xinjiang, and the strains were isolated and purified under anaerobic conditions using CMC-Na primary screening medium, bacteria capable of degrading cellulose were screened by Congo red staining, and the enzymatic activity of re-screened strains was determined, followed by 16S rDNA sequencing analysis of the strains and construction of a phylogenetic tree. The results showed that a total of 12 anaerobic bacterial strains with cellulose degradation ability were screened from horse cecum, which were identified as Lactobacillus agilis, Enterococcus hirae, Providencia rettgeri, Morganella morganii and Enterococcus faecalis, with one strain of Lactobacillus agalactiae (F2-A4) showed the highest cellulase activity of 14.841 U/mL. The study indicates that the anaerobic strains screened in the study are expected to provide strain resources of candidate bacteria for the development and application of feed microbial additives. [ABSTRACT FROM AUTHOR]

Copyright of Environmental Science & Technology (10036504) is the property of Editorial Board of Environmental Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Static facultative composting is one of the most widely-used, cost-effective, lightweight, and simple technologies to utilize local resources in modern agriculture. More than 60% of livestock and poultry manure (especially pig manure) can be treated using static composting. Static facultative composting can also create an aerobic environment with low porosity and limited depth of air diffusion within the heap, resulting in the low metabolic activity of microorganisms. Degradation of organic matter can be inevitably delayed, due to the long fermentation cycles, low fermentation temperatures, incomplete harmlessness, and low product maturity. Alternatively, the straw can be added to adjust the physical structure, oxygen content, and C/N ratios of the heap, in order to effectively improve the rot degree of static facultative compost products for the short rot cycle. This study aims to explore the effects of straw control on the maturity and microbial community structure of static facultative composting, especially on pathogenic bacteria. The corn straw was taken to regulate the physical structure and C/N ratio of the pile. A 90-day static facultative composting experiment was conducted using traditional natural fermentation. A systematic investigation was made to clarify the maturation index, fecal coliforms, and microbial community structure in the static facultative composting. The composting device was set as a 100 L flanged iron hoop bucket. Two treatments were set up in total. The control group was set without pig manure to label as the P treatment. The mixed compost of pig manure and corn straw was labeled as the PC treatment. The wet base mass ratio of 4:1 was selected without ventilation and heap turning. The results showed that the straw regulation increased the porosity of the compost (increased by 19.41%), and then promoted the diffusion of oxygen to the interior of the compost for the better degradation of organic matter by aerobic microorganisms. Specifically, the contents of phytotoxic substances were reduced (such as NH4+ -N and DTN) to improve the compost maturity. The seed germination indexes were 40.84% (P) and 114.60% (PC), respectively, in the two groups of compost products. As such, the compost maturation was accelerated during this time. The number of fecal coliforms reached the hygienic safety standard after 30 to 40 days of natural fermentation. Furthermore, the activity of fecal coliforms depended on the temperature of the pile, NH4+ -N, and organic acid content. The corn straw was added to improve the diversity of bacteria and synergistic effect. Firmicutes, Actinobacteria, Proteobacteria, and other phylum related to lignocellulosic degradation were the dominant microbial phylum in the reactor, where the aerobic, facultative, and anaerobic microbial stratification was formed from the aerobic to anaerobic bacteria from the top to the bottom. Therefore, the corn straw regulation can be expected to increase the aerobic area of the pile in the process of static composting. The harmless and mature degree can be promoted in the static composting of pig manure. The finding can provide the theoretical basis and technical standardization support for the static composting of livestock and poultry manure. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Modern Laboratory Medicine is the property of Journal of Modern Laboratory Medicine Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

【Objective】 Based on the long-term positioning experiment of organic carbon source material application, the response characteristics of rice rhizosphere anaerobic microbial community diversity to organic carbon source material input in Erhai lake basin were analyzed. 【Method】 Three treatments as non-fertilizer（CK）, chemical fertilizer（T1） and corn straw combined with chemical fertilizer（T2） were set to analyze the diversity characteristics of rice rhizosphere anaerobic microbial communities based on nitrogen conversion functional genes（nifH） and carbon conversion functional genes（cbbL）. The correlation between soluble N and P contents in soil and anaerobic microbial population was analyzed using redundancy analysis（RDA）. 【Result】 The results of Alpha and Beta diversity analysis showed that the Observed species, Shannon index and Chao1 index significantly improved（P<0.05）, and the difference of anaerobic microbial community structure significantly enhanced. Moreover, long-term application of organic carbon source material significantly increased the relative abundance of Proteobacteria and Cyanobacteria（P<0.05） at the phylum level. At the genus level, the population abundance of Methylibium and Bradyrhizobium increased, while the population abundance of Paraburkholderia decreased. In addition, the relative abundance of Cupriavidus taiwanensis and Alkaliphilus oremlandii significantly increased at species level（P<0.05）,however, Azohydromonas lata and Sulfuricaulis limicola decreased（P<0.05）. The results of redundancy analysis showed that soluble N had the highest resolution to the anaerobic microbial community. 【Conclusion】 In the high carbon storage farmland of Erhai lake basin, corn straw combined with chemical fertilizer mainly affected the community structure, physiological and ecological functions of rice rhizosphere anaerobic microorganisms by regulating the content of soluble nitrogen in the soil, and then affected their carbon and nitrogen conversion process. The results of the study have a certain role in promoting the accurate prediction of the changes of carbon, nitrogen and microbial structure in rice field and their influencing pathways, and can provide a theoretical basis for the optimization of regional farmland ecosystem management measures and the reasonable protection of farmland ecosystem. [ABSTRACT FROM AUTHOR]

Corn stalks have been traditionally disposed of by in-situ incineration or for the production of animal feed, due to the main crop residues in northeastern China. However, the conventional treatments of corn stalks have posed a great threat to the environment and resource utilization in recent years. Alternatively, biomass materials (corn stalks) can be widely expected to replace wood preparation in paper production. Different pretreatments can be utilized to improve the quality of pulp made from corn stover. The common-used pulping pretreatment can include various physical, chemical, and biological reactions. This study aims to explore the possibility and feasibility of a co-culture procedure of anaerobic microorganisms and yeast to pretreat the corn stalks. The culture medium was firstly prepared in the experiment, and then the resulting goat rumen fluid was filtered and centrifuged, where the centrifuged supernatant was used for the identification. After that, the supernatant of rumen fluid (anaerobic fungi: Pecoramyces sp.) and Saccharomyces cerevisiae S1145 were added to the medium for the simple co-culture. The components of the naturally air-dried corn stalks were separated, where the corn stalk husks were collected, crushed, and sieved, and the shredded husks (as a substrate) were added to the medium for the simple co-cultivation at 39°C for 72 hours. The results show that the Saccharomyces cerevisiae presented the ethanol in the metabolites of fermentation broth under the action of rumen fungi, indicating that the rumen fungi and yeast were co-cultured in vitro. The content of Saccharomyces cerevisiae was greatly contributed to the metabolism. The ethanol content in the product reached the maximum when adding 5ml of Saccharomyces cerevisiae, accounting for 32.09% of the total metabolite content. The ethanol content was increased by 23.04 percentage points with Saccharomyces cerevisiae, compared with the control without. The co-culture process of anaerobic fungi and Saccharomyces cerevisiae was utilized to pretreat the corn stalk bark, where the Saccharomyces cerevisiae was improved the ethanol production. The enzyme preparation was normally used to enzymatically hydrolyze plant cellulose in the conventional second-generation cellulosic ethanol production. Nevertheless, the enzyme preparation cannot be reused during processing, leading to the high production cost of cellulosic ethanol. Taking the rumen of ruminants as a bionic object, the living environment of anaerobic microorganisms was simulated in vitro to create the conditions for the sustainable production of cellulosic ethanol. Consequently, this experiment provided a new way to treat the corn stalks. The corn stalks after biological treatment can be used to produce the biomass pulp. The experiments have verified that the rumen anaerobic microorganisms and Saccharomyces cerevisiae can self-reproduce the corn in an artificial biomimetic environment, indicating the feasibility of straw to produce ethanol. The treatment and reuse of corn stalks can greatly contribute to the economic benefits of corn stalk pulping, while reducing the overall cost consumption for the high resource utilization. [ABSTRACT FROM AUTHOR]

Silage is an important livestock feed resource, which plays an important role in the development of animal husbandry, which is processed by anaerobic fermentation of microorganisms on the leaf surface to better preserve nutrients. Lactobacillus is main microorganism in silage, which can produce lactic acid by fermentation with soluble sugar, reduce pH value of silage, create acidic environment quickly, inhibit the growth of harmful microorganisms and improve the fermentation quality of silage. The paper reviews the research and application of lactic acid bacteria in silage from different sources, to provide reference for the development and application of lactic acid bacteria preparation. [ABSTRACT FROM AUTHOR]

[Objective] This paper studied the characteristics of the microbial community in purple soil pond mud and its relationship with environmental factors. [Method] Using slightly alkaline purple soil as the substrate to simulate the purple soil pond culture process, the environmental factors and microbial species of the pond mud in spring, summer and autumn were determined, and the correlation analysis was carried out by redundancy analysis. [Results] (1) SOM, TN, TP, TK and other nutrients in pond mud showed an increasing trend, and they accumulated significantly more during spring and summer. (2) The density of pond mud microorganisms (aerobic or facultative anaerobic) gradually decreases, the species diversity gradually increases, and the community uniformity does not change much. (3) Proteobacteria and Bacteroides in pond mud in spring, summer and autumn are all dominant categories; not only probiotics such as nitrifying bacteria and actinomycetes, which are beneficial to fisheries, but also Flavobacterium Pathogenic microorganisms such as Enterobacter, Aeromonas and Pseudomonas. (4) RDA analysis showed that SOM, TP, and AP are the main environmental factors that affect the diversity of the microbial community in pond mud, and have a significant negative correlation with microbial density (P<0.05); The main environmental factors of functional microbes are significantly negatively correlated with most microbes (P<0.05), positively correlated with probiotics, and negatively correlated with harmful microorganisms except Enterobacteriaceae (P<0.05). (5) The abundance of probiotics is highest in pond mud in summer and the lowest in pond mud in spring, and the abundance of harmful bacteria is highest in pond mud in spring. [Conclusion] The environmental factors of the purple soil pond mud are the main influencing factors of the microbial community structure, and the microbial community in the pond mud is not only the ecological restoration function library, but also the pathogen reservoir of aquaculture products. Among them, the abundance of harmful bacteria in the pond mud is the highest in spring, so Disease prevention measures should be strengthened in spring. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Yeast industry provides enormous economic and social benefits for the sugarcane biomass industry. However, yeast industrial wastewater is characterized by high concentration of chemical oxygen demand (CODcr), high chromaticity, high concentration of sulfate and difficult biodegradation, which leads to many issues of the environment. The treatment process of wastewater has the problem that discharge water is difficult to reach the standard and its cost is too high, which has become a bottleneck restricting the development of domestic yeast enterprises. Biotechnology is currently widely used, but the results are still not up to standard. Therefore, biological treatment should be supplemented by other methods for in-depth treatment. In this paper, yeast wastewater was treated by adding photosynthetic bacteria to strengthen anaerobic sludge. The ultrafiltration membrane was used to filter the separated dialysate wastewater as the test object. A small UASB anaerobic reactor was designed. The initial MLSS (mixed liquid sludge concentration) value of the inoculated sludge in the reactor was 4 820 mg/L, and the reactor temperature was kept at 32 ℃. The hydraulic retention time was 48 h, and the influent pH value was controlled between 6.8 and 7.0. At the start-up stage of the anaerobic reactor, glucose, ammonium nitrate and potassium dihydrogen phosphate were used as C, N and P source, respectively, and an appropriate amount of trace elements were added to prepare a nutrient solution with a ratio of 300:5:1 of C:N:P. Yeast wastewater and nutrient solution were mixed and configured into water samples with mass concentration gradient of 3 000-3 500, 7 000-7 500, 10 000-10 500 and 14 000-15 000 mg/L, respectively. The water samples were added to the reactor in a gradient form from low concentration to high concentration, and the batch test was carried out until the organic concentration of wastewater reached the concentration of raw water. After the treatment effect of the reactor was stabilized, the photosynthetic bacteria were added to the domesticated anaerobic sludge, and the concentration of the bacterial suspension was 1.2×1010 mL-1 as determined by the Meish turbidimetry method, and the addition amount was 1 mL/L, the inflow was 900-1 000 mL with HRT of 48 h, and the continuous illumination by fluorescent lamp was used. After the reactor was stabilized, the water quality was tested and analyzed after continuous operation for 9 cycles. The CODcr and chromaticity changes of wastewater during anaerobic treatment ， the OTU distribution of microorganisms during the addition of photosynthetic bacteria, the species of anaerobic sludge bacteria and sludge, and the changes in the number of archaeological clustering results were investigated. The results showed that the CODCr and chroma removal rates of yeast wastewater treated by anaerobic UASB reactor were significantly increased from 58.20% to 75.12% and 47.50% to 62.04%, respectively, which indicated that the effect of photosynthetic bacteria on the anaerobic biological treatment process has significantly increased. From the analysis of microbial diversity data, it was found that in the process of anaerobic sludge domestication and photosynthetic bacteria optimization, the dominant species was accumulated, the specificity was enhanced, and the number of species was reduced. Photosynthetic bacteria and other heterotrophic bacteria have a symbiotic relationship, and after the addition of the sludge, the dominant microorganisms of methane increased significantly, so as to improve the treatment effect of the anaerobic system. The results of this study provide a technical route for the effective treatment of high-concentration industrial organic wastewater. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Modern Laboratory Medicine is the property of Journal of Modern Laboratory Medicine Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to provide theoretical support for the optimization of anaerobic ammonium oxidation (ANAMMOX)technology， high-throughput sequencing technology was used to study the microbial community structure and its evolution in an ANAMMOX reactor. The results showed that the reactor achieved nitrogen removal rate up to 1.04kg·N·m-3·d-1 after 61 days. The total nitrogen removal rate was above 75%.The microbial diversity in the reactor was very abundant，including Proteobacteria，Chloroflexi， Chlorobi，Planctomycetes， etc. The microbial community structure tended to be stable with the running process of the reactor. The proportion of Proteobacteria and Planctomycete， associated with denitrification， totally achieved over 40%. The proportion of ANAMMOX bacteria belonging to Planctomycete increased gradually with reactor operation， which was the main reason for denitrification efficiency improvement.The ANAMMOX bacteria Candidatus Kuenenia category dominated in reactor about 14%. A small number of Candidatus Brocadia genus also existed in the reactor. [ABSTRACT FROM AUTHOR]

To removal the raw materials of bisphenol A (such as phenol, acetone, and molecules of bisphenol A dissolved in the acetone) and various phenolic compounds, which are hard to be detected, from bisphenol A producing wastewater, the adaptability and treating efficiency of microorganisms to this type of wastewater are tested by static cultivating and acclimating the anaerobic granular sludge. The results of static adaptability tests show that the microorganisms adapt to this type of wastewater well. The COD is decreased by 58% when the contact time is 6 hours. After acclimating the microorganisms for 60 days, the COD removal efficiency can get to 50% with hydraulic retention time of 9 hours. Great diversity of microorganisms both inside and on the surface of the granular sludge can be found when using SEM to observe the granular sludge in the reactor before and after the experiment. [ABSTRACT FROM AUTHOR]

Objective To evaluate the antimicrobial efficacy of Fufang Bingpeng irrigant and Bingpeng irrigant on four endodontic pathogen bacteria. Methods The agar dilution method was used to observe the antimicrobial activity of Fufang Bingpeng irrigant, Bingpeng irrigant against four selected endodontic pathogen bacteria (Porphyromonas gingivalis, Prevotella intermedius, Fusobacterium nucleatum, Enterococcus faecalis). Minimum inhibitory concentration and minimum bactericidal concentration was examined. Results Two irrigants had the antimicrobial activity against the anaerobic microorganisms. The antimicrobial efficacy of Fufang Bingpeng irrigant was better than that of Bingpeng irrigant. Compared with others, Enterococcus faeca.lis had the strongest resistance. Conclusion Fufang Bingpeng irrigant has good antibacterial activity. As a root canal irrigant, Chinese medicine alteratives might be advantageous. [ABSTRACT FROM AUTHOR]