The accumulator is used as a pressure compensation device to realize deep-sea microbe gastight sampling. Four key states of the accumulator are proposed to describe the pressure compensation process and a correspondin...The accumulator is used as a pressure compensation device to realize deep-sea microbe gastight sampling. Four key states of the accumulator are proposed to describe the pressure compensation process and a corresponding mathematical model is established to investigate the relationship between the results of pressure compensation and the parameters of the accumulator. Simulation results show that during the falling process of the sampler, the accumulator' s real opening pressure is greater than its precharge pressure; when the sampling depth is 6000 m and the accumulator' s precharge pressure is less than 30 MPa, to increase the accumulator' s precharge pressure can improve pressure compensation results obviously. Laboratory experiments at 60 MPa show that the acctunulator is an effective and reliable pressure compensation device for deep-sea microbe samplers, The success in sea trial at a depth of 2000 m in the South China Sea shows that the mathematical model and laboratory experiment results are reliable.展开更多
Three typical rural-suburban-urban artificial wetlands Pinus elliottii forest in Nanchang City were selected as research objects to mensurate the soil nutrient content.And the annual average values and seasonal change...Three typical rural-suburban-urban artificial wetlands Pinus elliottii forest in Nanchang City were selected as research objects to mensurate the soil nutrient content.And the annual average values and seasonal changes of microbes in forest soil were analyzed.The results showed that soil bulk density,total phosphorus (TP) and pH increased,while soil organic carbon (SOC),total nitrogen (TN) declined with rural-to-urban gradient.At different eco-boundary,annual average values showed that actinomycetes quantity bacteria quantity fungi quantity.Total microbe number was urban suburb rural areas.The number of bacteria and fungi was urban suburbs rural areas,but the number of actinomycetes was suburb urban rural areas.Eco-boundary,season and microbes actinomycetes and fungi reached an extreme significant level (P 0.001).Bacteria in soil at different eco-boundary had significant effects,but season had no significant effect on bacteria.Eco-boundary and season had a very significant interaction on actinomycetes and fungi (P 0.001),but they had no significant interaction on bacteria (P 0.05).Eco-boundary showed significantly positive correlation with actinomycetes and fungi (P 0.001),but season had no significant corelation with microbes.In conclusion,urbanization process caused the physical-chemical properties changes of forest soil and affected the amount of soil microbes obviously.展开更多
[Objective] The research aimed to lay the foundation for high-efficiency biological degradation microbial inoculums. [Method] under the 60℃ temperature the cellulolytic microbes in pig manure were isolated and determ...[Objective] The research aimed to lay the foundation for high-efficiency biological degradation microbial inoculums. [Method] under the 60℃ temperature the cellulolytic microbes in pig manure were isolated and determined the CMCase and Fpase,then proceeded the 16S rRNA gene analysis. [Result]The results showed that:BC1 and BC3 strains characterized higher carboxymethyl cellulose enzyme activity and higher filter paper activity,but their difference was small,then the 16S rDNA sequence of BC1 and BC3 strains were related to pseudomonas sp. (98% and 99% similarities,respectively).[Conclusion] the experiment laid foundation for high-efficiency biological heating agent.展开更多
The microbial consortium GF-20(GF-20) can efficiently decompose corn stover at low temperatures. The present study explored the key microbes of GF-20 and evaluated different culture conditions on its composition stabi...The microbial consortium GF-20(GF-20) can efficiently decompose corn stover at low temperatures. The present study explored the key microbes of GF-20 and evaluated different culture conditions on its composition stability to promote the utilization of corn stover decomposing microbes in low temperature regions. GF-20 was subcultured to the 15 th generation under different temperatures, pHs, carbon, and nitrogen sources. Then, the dynamics of fermenting pH, cellulose enzyme activities, carbohydrate concentration, and oxidation reduction potential were determined to estimate the degradation efficiency of corn stover with GF-20. Furthermore, the structural stability and functional microbes of GF-20 were identified on the basis of PCR-denaturing gradient gel electrophoresis(DGGE) profiling and principal component analysis. The results showed that the offspring of GF-20 subcultured under different temperatures(4–30°C) and pH(6.0–9.0) conditions maintained stable growth, decomposition function, and composition structure. Furthermore, consortia GF-20 had a stable composition structure, which induced GF-20 to secrete cellulose and promote substrate decomposition as corn stover and ammonium were used as sources of carbon and nitrogen, respectively. According to the PCR-DGGE profiles, the key strains of GF-20 were determined to be Bacillus licheniformis, Cellvibrio mixtus subsp. mixtus, Bacillus tequilensis, Clostridium populeti, and Clostridium xylanolyticum.展开更多
The thermochemical kinetics of the rare earth ternary complex Sm(Gly) 4Im(ClO 4) 3·2H 2O (Gly glycine, Im imidazole) reacting with microbes (escherichia coli, bacillus subilis, staphylococcus aureus) was st...The thermochemical kinetics of the rare earth ternary complex Sm(Gly) 4Im(ClO 4) 3·2H 2O (Gly glycine, Im imidazole) reacting with microbes (escherichia coli, bacillus subilis, staphylococcus aureus) was studied by means of Calvet microcalorimeter. The rate constant k of microbe growth was calculated, and the inhibition effect of these complexes to microbes was compared.展开更多
The bio-sandstone, which was cemented by microbe cement, was firstly prepared, and then the microstructure evolution process was studied by X-ray computed tomography (X-CT) technique. The experimental results indica...The bio-sandstone, which was cemented by microbe cement, was firstly prepared, and then the microstructure evolution process was studied by X-ray computed tomography (X-CT) technique. The experimental results indicate that the microstructure of bio-sandstone becomes dense with the development of age. The evolution of inner structure at different positions is different due to the different contents of microbial induced precipitation calcite. Besides, the increase rate of microbial induced precipitation calcite gradually decreases because of the reduction of microbe absorption content with the decreasing pore size in bio-sandstone.展开更多
Some strains and culture of bacteria which are able to decolorize dyes and degrade polyvinyl alcohol(PVA) were isolated and selected. A pilot scale facultative anaerobic-aerobic biological process was applied for trea...Some strains and culture of bacteria which are able to decolorize dyes and degrade polyvinyl alcohol(PVA) were isolated and selected. A pilot scale facultative anaerobic-aerobic biological process was applied for treatment of textile wastewater containing dyes and PVA. Activated carbon adsorption was used as a tertiary treatment stage, and residual sludge from clarifier returned to the anaerobic reactor again. The pilot test were carried out with two systems. One was inoculated by acclimated sludge, and the another was adding the mixed culture of dye-decoloring and PVA-degrading bacteria for forming biological films, the latter was observed to be more effective than the former. The test has run normally for ten months with a COD loading of 2.13 kg/m3/day, a BOD5 loading of 0.34 kg/m3/day in anaerobic reactor; a COD loading of 1.71 kg/m3/day, a BOD5 loading 0.44 kg/m3/day in aerobic reactor. The pollutants removal efficiency by adding microbes was about 20% higher than that by acclimated sludge. The average removal efficiency of COD stood about 92%, BOD5 97%, PVA 90% and decolorization 80%. The other parameters of effluent quality are also satisfactory.展开更多
[Objective] The aim was to study on effect of different temperatures on microbes and its quality of green pepper during circulation. [Method] Measurement was conducted on change of colibacillus, salmonella, Listeria n...[Objective] The aim was to study on effect of different temperatures on microbes and its quality of green pepper during circulation. [Method] Measurement was conducted on change of colibacillus, salmonella, Listeria number, and its quality of green pepper stored at 9 and 20 ℃ respectively. The green peppers stored at 9 ℃ for 16 d were under simulated sale. In addition, effects of microbe number of green peppers stored at 20 ℃ for 4 d by different washing methods were measured. [Result] Indices of green pepper were different when green peppers were stored for 16 d at 9 ℃ and sold at 20 ℃ after 16 d storage. Specifically, under the former condition, sensory quality, weight-loss rate, Vc content, chlorophyll content and soluble protein were 4.1, 1.79%, 95.6, 20.3, and 93.3 mg/100 g; under the latter condition, the corresponding indices were 3.3, 3.87%, 81.2, 16.5, 85.6 mg/100 g, respectively. Colibacillus numbers for green pepper stored 16 d at 9 ℃, sold for 1 d at 20 ℃ after 16 d storage and stored for 4 d at 20 ℃ were 46, 3.2×103 and 3.1×104 cfu/g; during the test, salmonella and Listeria were not found; colibacillus in green pepper could be eliminated by 1×10-3 ml/L of chloros and most colibacillus in green pepper could be cleared away by 1 drop/L of detergent and running water. [Conclusion] Stored at 9 ℃, quality of green pepper could be better preserved and colibacillus propagation could be controlled.展开更多
Production and storage-transportation of crude oil can not only give rise to soil pollution but also destroy ecological environment. Degradation of microbes for oily soil was studied with the instnunent, Geofina Hydro...Production and storage-transportation of crude oil can not only give rise to soil pollution but also destroy ecological environment. Degradation of microbes for oily soil was studied with the instnunent, Geofina Hydrocarbon Meter (GHM), by experimental analysis qualitatively and quantitatively in the paper. Analytical result showed that the crude oil could be considerably degraded by eating-oil microbes in oily soil and the number of eating-oil microbes increased while the working hours of oil-well risi...展开更多
Microbes were cultured from the samples at various depths in a weathering profile of RE-bearing granite in Gonghe RE mine, Guangdong Province. The cultured microbes, existing at a depth of 0.2 similar to 12 in and bei...Microbes were cultured from the samples at various depths in a weathering profile of RE-bearing granite in Gonghe RE mine, Guangdong Province. The cultured microbes, existing at a depth of 0.2 similar to 12 in and being more plentiful within 3 in in the profile, include bacteria ( Bacillus, Enterobacter, Escherichia, Alkaligenes, Neisseria, Staphylococcus and anaerobic bacteria such as Clostridium), fungi ( Aspergillus niger, Aspergillus flavus, Penicillium, Mucor and Saccharomycete) and actinomyces. Experiments were made under room temperature by using solutions of the cultured microbes and their metabolites, compared with distilled water and the culture solution without microbes, to leach RE from the sample of the weathering crust. The results are shown by the experiments: (1) The mixed microbes cultured from the profile and their metabolites increase the quantity of RE leached from the sample and reduce the pH of the solutions. (2) The ability to leach RE from the sample varies with various microbes, decreasing in a sequence of fungi ( Mucor, saccharomycete, Aspegillus and Penicillium), zymotic bacilli (Enterobacter, Escherichia etc.), Staphylococcus, zymotic Bacillus, actinomyces and Alkaligenes. (3) The RE leached with bacteria is mainly related to the pH value of the solutions influenced by the metabolites of the bacteria; whereas that leached with fungi is mainly related to the adsorption and imbibition of RE by the fungi and the complexing of RE with their metabolites. (4) Compared with that leached with ammonium sulfate, the fractionation of the RE leached with microbes is characterized by higher delta (Ce), lower delta (Eu) and lower ratios of N-La/Sm and N-Gd/Yb . The result of the fractionation of RE accords with the distribution of RE in the various layers of a profile of weathering crust of granite in South China. The experimental results indicate that microbes and their metabolites should play a positive role in the mobilization, migration and fractionation of RE in the weathering crust in South China.展开更多
The quantity of soil microbes and the structure of ammonium oxidizing bacterial (AOB) community were analyzed using the dilution plate counting and most probable number method (MPN), and denaturing gradient gel el...The quantity of soil microbes and the structure of ammonium oxidizing bacterial (AOB) community were analyzed using the dilution plate counting and most probable number method (MPN), and denaturing gradient gel electrophoresis (DGGE), respectively. Fertilizer application tended to increase the number of soil microbes and alter the AOB community compared to the control with no fertilizer application (CK). Among the eight fertilizer treatments, soil samples from the treatments of mineral fertilizers (e.g., N, P, K) in combination with farmyard manure (M) had greater number.s of soil microbes and more complex structure of AOB community than those receiving mineral fertilizers alone. The principal component analyses (PCA) for ammonium oxidizing bacterial community structure showed that the eight fertilizer treatments could be divided into two PCA groups (PCA1 and PCA2). For the soil sampled after rice harvest, PCA1 included NP, NM, NPM and NPKM fertilizer treatments, while PCA2 was consisted of CK, N, M and NPK fertilizer treatments. For soil samples collected after wheat harvest, PCA1 was consisted of M, NM, NPM and NPKM fertilizer treatments, while PCA2 was composed of CK, N, NP and NPK fertilizer treatments. For a given rotation, the richness of AOB community in PCA1 was greater than that in PCA2. In addition, AOB community structure was more complex in the soil after rice harvest than that after wheat harvest. The results indicated that different fertilizer treatments resulted in substantial changes of soil microbe number and AOB community. Furthermore, mineral fertilizers (N, NP, NPK) combined with farmyard manure were effective for increasing the quantity of soil microbes, enriching AOB community, and improving the soil biofertility.展开更多
Diversity analysis on secondary metabolites of Antarctic microbes, Rhodococcus sp. NJ-008 and Pseudomonas sp. NJ-011, together with the structural elucidation of some purified compounds, has been carried out for under...Diversity analysis on secondary metabolites of Antarctic microbes, Rhodococcus sp. NJ-008 and Pseudomonas sp. NJ-011, together with the structural elucidation of some purified compounds, has been carried out for understanding of their chemical constituents. The methanol extracts of Rhodococcus sp. NJ-008 and Pseudomonas sp. NJ-011 were subjected to HPLC-TOF MS test for diversity analysis on secondary metabolites, respectively. The chemical constituents of NJ-011 are mainly N-containing compounds including some alkaloids and short polypeptides, while those of NJ-008 are not N-containing ones. Three compounds were also isolated and identified from extract of NJ011 by different column chromatography and preparative HPLC, and their structures were elucidated as b-carboline (1), 3-benzylhexahydropyrrolo[1,2-a]pyrazine-1,4-dione (2) and 3-isobutylhexahydropyrrolo[1,2-a]pyrazine-1,4-dione (3) by comparison of TOF MS, 1Hand 13C-NMR data with those reported. More microbial material of Pseudomonas sp. NJ-011 should be needed for exploration of the minor constituents with complicated structures.展开更多
BOD measurements in presence of cobalt, nickel, copper, zinc, silver and cadmium are reported using wastewater from dairy industry as a seed. Extent of inhibition in BOD is studied for variables like, concen-tration o...BOD measurements in presence of cobalt, nickel, copper, zinc, silver and cadmium are reported using wastewater from dairy industry as a seed. Extent of inhibition in BOD is studied for variables like, concen-tration of metal ions (0.2 mM to 1.4 mM), pH (3 to 8) and temperature of incubation (15℃, 20℃, 25℃, 30℃ and 35℃). Results of BOD inhibition are supported by absorbance measurement (OD600) studies of microbial matter preserved in Luriya broth medium. OD measurement results are used to derive minimum inhibitory concentration, i.e., threshold concentration of each metal showing toxicity towards microbes. Sil-ver is found to be the most toxic element.展开更多
Hypertension is an important global public health issue because of its high morbidity as well as the increased risk of other diseases.Recent studies have indicated that the development of hypertension is related to th...Hypertension is an important global public health issue because of its high morbidity as well as the increased risk of other diseases.Recent studies have indicated that the development of hypertension is related to the dysbiosis of the gut microbiota in both animals and humans.In this review,we outline the interaction between gut microbiota and hypertension,including gut microbial changes in hypertension,the effect of microbial dysbiosis on blood pressure(BP),indicators of gut microbial dysbiosis in hypertension,and the microbial genera that affect BP at the taxonomic level.For example,increases in Lactobacillus,Roseburia,Coprococcus,Akkermansia,and Bifidobacterium are associated with reduced BP,while increases in Streptococcus,Blautia,and Prevotella are associated with elevated BP.Furthermore,we describe the potential mechanisms involved in the regulation between gut microbiota and hypertension.Finally,we summarize the commonly used treatments of hypertension that are based on gut microbes,including fecal microbiota transfer,probiotics and prebiotics,antibiotics,and dietary supplements.This review aims to find novel potential genera for improving hypertension and give a direction for future studies on gut microbiota in hypertension.展开更多
The aim of this study is to investigate microbial structures and diversities in five active hydrothermal fields' sediments along the Eastern Lau Spreading Centre (ELSC) in the Lau Basin (southwest Pacific). Micro...The aim of this study is to investigate microbial structures and diversities in five active hydrothermal fields' sediments along the Eastern Lau Spreading Centre (ELSC) in the Lau Basin (southwest Pacific). Microbial communities were surveyed by denatured gradient gel electrophoresis (DGGE) and clone library analysis of 16S rRNA genes. The differences in microbial community structures among sediment samples from the five deep-sea hydrothermal sites were revealed by DGGE profiles. Cluster analysis of DGGE profiles sepa- rated the five hydrothermal samples into two groups. Four different 16S rRNA gene clone libraries, repre- senting two selected hydrothermal samples (19-4TVG8 and 19-4TVG11), were constructed. Twenty-three and 32 phylotypes were identified from 166 and 160 bacterial clones respectively, including Proteobacteria, Bacteroidetes, Firmicutes, Nitrospirae and Planctomycetes. The phylum Proteobacteria is dominant in both bacterial libraries with a predominance of Gamma-Proteobacteria. A total of 31 and 25 phylotypes were obtained from 160 and 130 archaeal clones respectively, including Miscellaneous Crenarchaeotic Group, Marine Group Ⅰ and Ⅲ, Marine Benthic Group E, Terrestrial Hot Spring Crenarchaeota and Deep-sea Hy- drothermal Vent Euryarchaeota. These results show a variety of clones related to those involved in sulfur cycling, suggesting that the cycling and utilization of sulfur compounds may extensively occur in the Lau Basin deep-sea hydrothermal ecosystem.展开更多
Bruguiera sexangula (Lout) Poir., a threatened mangrove tree, was inoculated with beneficial microbes in a nursery to assess any improvements in growth and bio- mass. From soil samples from the rhizosphere of B. sex...Bruguiera sexangula (Lout) Poir., a threatened mangrove tree, was inoculated with beneficial microbes in a nursery to assess any improvements in growth and bio- mass. From soil samples from the rhizosphere of B. sexangula in a mangrove forest in Panangadu of Kerala India, nitrogen-fixing bacteria Azotobacter chroococcum and Azospirillum brasilense were isolated. The phosphatesolubilising bacterium Bacillus megaterium and potassiummobilizing bacteria Frateruria aurantia were also isolated and cultured on suitable media. Later, ripe propagules of B. sexangula were collected from matured trees and raised in sterilized soil bags (13 × 25 cm) containing sterilized soil and sand (2:1 ratio). The cultured beneficial microbes were propagated and used to inoculate the ripe propagules of B. sexangula and maintained in the nursery for 6 months. After 6 months, growth and biomass of the inoculated propagules were greater than for the uninoculated control propagules. Shoot length, number of leaves, stem girth and root length were also significantly greater than in the controls. This study showed that the mangrove-specific beneficial microbes influenced the growth of B. sexangula展开更多
Earthworm and microbe are very important soil organisms. They play an important role in the stability of ecosystem and the bioavailability of nutrients and heavy metals in soils. This article reviewed the function of ...Earthworm and microbe are very important soil organisms. They play an important role in the stability of ecosystem and the bioavailability of nutrients and heavy metals in soils. This article reviewed the function of earthworm and microbes in improving soil structure and controlling soil nutrients as well as their effects on the bioavailability of heavy metals in soil through bioabsorption, enrichment, precipitation, dissolution, and oxidation-reduction. The aim is to provide a certain theoretical basis for modern agricultural production.展开更多
A pot culture experiment was carried out in a glasshouse to compare the physiology and growth of sweet corn plants (Zea mays L. cv. Honey Bantam) grown under organic and chemical fertilizations with or without microbi...A pot culture experiment was carried out in a glasshouse to compare the physiology and growth of sweet corn plants (Zea mays L. cv. Honey Bantam) grown under organic and chemical fertilizations with or without microbial inoculation (MI). The organic fertilizer used was fermented mainly using rice bran and oil mill sludge, and the MI was a liquid product containing many beneficial microbes such as lactic acid bacteria, yeast, photosynthetic bacteria and actinomycetes. The application amounts of the organic fertilizer and chemical fertilizers were based on the same rate of nitrogen, phosphorus and potassium. Sweet corn plants fertilized with organic materials inoculated with beneficial microbes grew better than those without inoculation. There were no significant differences in physiology and growth of the sweet corn plants between treatments of chemical fertilizers with and without MI. Among the organic fertilization treatments, only the sweet corn plants with organic fertilizer and MI applied 4 weeks before sowing had similar photosynthetic capacityj total dry matter yield and ear yield to those with chemical fertilizers. Sweet corn plants in other organic fertilization treatments were weaker in physiology and growth than those in chemical fertilization treatments. There was no significant variance among chemical fertilization treatments at different time. It is concluded from this research that this organic fertilizer would be more effective if it was inoculated with the beneficial microbes. Early application of the organic fertilizer with beneficial microbes before sowing was recommended to make the nutrients available before the rapid growth at the early stage and obtain a yield similar to or higher than that with chemical fertilizations.展开更多
A novel esterase EstC10 from Bacillus sp. CX01 isolated from the deep sea of the Western Pacific Ocean and the functionalities of EstC 10 was characterized. At present, the reports about the kinetic resolution ofracem...A novel esterase EstC10 from Bacillus sp. CX01 isolated from the deep sea of the Western Pacific Ocean and the functionalities of EstC 10 was characterized. At present, the reports about the kinetic resolution ofracemic methyl 2-chloropropionate were quite rare. So we developed deep-sea microbial esterase EstC10 as a novel biocatalyst in the kinetic resolution of racemic methyl 2-chloropropionate and generate (R)-methyl 2-chloropropionate with high enantiomeric excess (〉99%) after the optimization of process parameters such as pH, temperature, organic co-solvents, surfactants, substrate concentration and reaction time. Notably, the optimal substrate concentration (80 mmol/L) of esterase EstC10 was higher than the kinetic resolution of another esterase, Estl2-7 (50 mmoFL). The novel microbial esterase EstC10 identified from the deep sea was a promising green biocatalyst in the generation of (R)-methyl 2-chloropropionate as well of many other valuable chiral chemicals in industry.展开更多
Laboratory and in situ experiments were done to investigate the influences of cultivation on temperate semi arid grassland (for 17 years spring wheat planted once every two years without fertilization) on soil N ...Laboratory and in situ experiments were done to investigate the influences of cultivation on temperate semi arid grassland (for 17 years spring wheat planted once every two years without fertilization) on soil N 2O emission and quantitative variations of related soil microbes. In the laboratory (25℃ and soil moisture 18%), cultivation increased soil transformations of fertilizer nitrogen (100 μg N/g as NaNO 3, urea, or as urea with dicyandiamide 1 μg N/g). The N 2O emissions from the cultivated and uncultivated soils with or without nitrogen additions were relatively low, and mainly originated from the nitrification. The soil N 2O emission due to cultivation decreased somewhat upon no fertilization or NaNO 3 addition, but significantly upon urea addition. The role of dicyandiamide as nitrification inhibitor was only considerable in the cultivated soil, and had small influence on decreasing N 2O emission in the two soils. The influence of cultivation on soil N 2O emission was also reflected by the number variations of microbes related with soil nitrogen transformation in the two soils. Compared to the uncultivated grassland, in situ ammonifiers and denitrifiers in the cultivated grassland quantitatively averagely increased, and aerobic no symbiotic azotobacters were quantitatively similar, leading to the continued decrease of organic matter content and the decrease of N 2O emission from the cultivated grassland soil.展开更多
文摘The accumulator is used as a pressure compensation device to realize deep-sea microbe gastight sampling. Four key states of the accumulator are proposed to describe the pressure compensation process and a corresponding mathematical model is established to investigate the relationship between the results of pressure compensation and the parameters of the accumulator. Simulation results show that during the falling process of the sampler, the accumulator' s real opening pressure is greater than its precharge pressure; when the sampling depth is 6000 m and the accumulator' s precharge pressure is less than 30 MPa, to increase the accumulator' s precharge pressure can improve pressure compensation results obviously. Laboratory experiments at 60 MPa show that the acctunulator is an effective and reliable pressure compensation device for deep-sea microbe samplers, The success in sea trial at a depth of 2000 m in the South China Sea shows that the mathematical model and laboratory experiment results are reliable.
基金Supported by Natural Science Foundation of Jiangxi Province(2007GQN1935)~~
文摘Three typical rural-suburban-urban artificial wetlands Pinus elliottii forest in Nanchang City were selected as research objects to mensurate the soil nutrient content.And the annual average values and seasonal changes of microbes in forest soil were analyzed.The results showed that soil bulk density,total phosphorus (TP) and pH increased,while soil organic carbon (SOC),total nitrogen (TN) declined with rural-to-urban gradient.At different eco-boundary,annual average values showed that actinomycetes quantity bacteria quantity fungi quantity.Total microbe number was urban suburb rural areas.The number of bacteria and fungi was urban suburbs rural areas,but the number of actinomycetes was suburb urban rural areas.Eco-boundary,season and microbes actinomycetes and fungi reached an extreme significant level (P 0.001).Bacteria in soil at different eco-boundary had significant effects,but season had no significant effect on bacteria.Eco-boundary and season had a very significant interaction on actinomycetes and fungi (P 0.001),but they had no significant interaction on bacteria (P 0.05).Eco-boundary showed significantly positive correlation with actinomycetes and fungi (P 0.001),but season had no significant corelation with microbes.In conclusion,urbanization process caused the physical-chemical properties changes of forest soil and affected the amount of soil microbes obviously.
基金Supported by Foundation of Henan Educational Committee(2010B530001)~~
文摘[Objective] The research aimed to lay the foundation for high-efficiency biological degradation microbial inoculums. [Method] under the 60℃ temperature the cellulolytic microbes in pig manure were isolated and determined the CMCase and Fpase,then proceeded the 16S rRNA gene analysis. [Result]The results showed that:BC1 and BC3 strains characterized higher carboxymethyl cellulose enzyme activity and higher filter paper activity,but their difference was small,then the 16S rDNA sequence of BC1 and BC3 strains were related to pseudomonas sp. (98% and 99% similarities,respectively).[Conclusion] the experiment laid foundation for high-efficiency biological heating agent.
基金supported by the National Natural Science Foundation of China (31760353 and 31560360)the National Key R&D Program of China (2017YFD0300804 and 2016YFD0300103)+2 种基金the earmarked fund for China Agriculture Research System (CARS-02-63)the Crop Science Observation & Experiment Station in Loess Plateau of North China, Ministry of Agriculture, China (25204120)the Advanced Talented Scholars of Inner Mongolia Agricultural University, China (NDYB2016-15)
文摘The microbial consortium GF-20(GF-20) can efficiently decompose corn stover at low temperatures. The present study explored the key microbes of GF-20 and evaluated different culture conditions on its composition stability to promote the utilization of corn stover decomposing microbes in low temperature regions. GF-20 was subcultured to the 15 th generation under different temperatures, pHs, carbon, and nitrogen sources. Then, the dynamics of fermenting pH, cellulose enzyme activities, carbohydrate concentration, and oxidation reduction potential were determined to estimate the degradation efficiency of corn stover with GF-20. Furthermore, the structural stability and functional microbes of GF-20 were identified on the basis of PCR-denaturing gradient gel electrophoresis(DGGE) profiling and principal component analysis. The results showed that the offspring of GF-20 subcultured under different temperatures(4–30°C) and pH(6.0–9.0) conditions maintained stable growth, decomposition function, and composition structure. Furthermore, consortia GF-20 had a stable composition structure, which induced GF-20 to secrete cellulose and promote substrate decomposition as corn stover and ammonium were used as sources of carbon and nitrogen, respectively. According to the PCR-DGGE profiles, the key strains of GF-20 were determined to be Bacillus licheniformis, Cellvibrio mixtus subsp. mixtus, Bacillus tequilensis, Clostridium populeti, and Clostridium xylanolyticum.
文摘The thermochemical kinetics of the rare earth ternary complex Sm(Gly) 4Im(ClO 4) 3·2H 2O (Gly glycine, Im imidazole) reacting with microbes (escherichia coli, bacillus subilis, staphylococcus aureus) was studied by means of Calvet microcalorimeter. The rate constant k of microbe growth was calculated, and the inhibition effect of these complexes to microbes was compared.
基金Funded by the National Natural Science Foundation of China(No.51072035),the Ph D Program’s Foundation of Ministry of Education of China(No.20090092110029)the Research Innovation Program for College Graduates of Jiangsu Province(No.CXZZ_0145)the Scientific Research Foundation of Graduate School of Southeast University(Nos.YBJJ1127 and YBPY1208)
文摘The bio-sandstone, which was cemented by microbe cement, was firstly prepared, and then the microstructure evolution process was studied by X-ray computed tomography (X-CT) technique. The experimental results indicate that the microstructure of bio-sandstone becomes dense with the development of age. The evolution of inner structure at different positions is different due to the different contents of microbial induced precipitation calcite. Besides, the increase rate of microbial induced precipitation calcite gradually decreases because of the reduction of microbe absorption content with the decreasing pore size in bio-sandstone.
文摘Some strains and culture of bacteria which are able to decolorize dyes and degrade polyvinyl alcohol(PVA) were isolated and selected. A pilot scale facultative anaerobic-aerobic biological process was applied for treatment of textile wastewater containing dyes and PVA. Activated carbon adsorption was used as a tertiary treatment stage, and residual sludge from clarifier returned to the anaerobic reactor again. The pilot test were carried out with two systems. One was inoculated by acclimated sludge, and the another was adding the mixed culture of dye-decoloring and PVA-degrading bacteria for forming biological films, the latter was observed to be more effective than the former. The test has run normally for ten months with a COD loading of 2.13 kg/m3/day, a BOD5 loading of 0.34 kg/m3/day in anaerobic reactor; a COD loading of 1.71 kg/m3/day, a BOD5 loading 0.44 kg/m3/day in aerobic reactor. The pollutants removal efficiency by adding microbes was about 20% higher than that by acclimated sludge. The average removal efficiency of COD stood about 92%, BOD5 97%, PVA 90% and decolorization 80%. The other parameters of effluent quality are also satisfactory.
基金Supported by National Science&Technology Pillar Program during the Eleventh Five-year Plan Period(2009BADB91309-6)Construction of Massive Vegetable Industry(CARS-25-E-01)Special Fund of Beijing Academy of Agriculture and Forestry for Innovation of Sciences and Technology(KJCX201102004)~~
文摘[Objective] The aim was to study on effect of different temperatures on microbes and its quality of green pepper during circulation. [Method] Measurement was conducted on change of colibacillus, salmonella, Listeria number, and its quality of green pepper stored at 9 and 20 ℃ respectively. The green peppers stored at 9 ℃ for 16 d were under simulated sale. In addition, effects of microbe number of green peppers stored at 20 ℃ for 4 d by different washing methods were measured. [Result] Indices of green pepper were different when green peppers were stored for 16 d at 9 ℃ and sold at 20 ℃ after 16 d storage. Specifically, under the former condition, sensory quality, weight-loss rate, Vc content, chlorophyll content and soluble protein were 4.1, 1.79%, 95.6, 20.3, and 93.3 mg/100 g; under the latter condition, the corresponding indices were 3.3, 3.87%, 81.2, 16.5, 85.6 mg/100 g, respectively. Colibacillus numbers for green pepper stored 16 d at 9 ℃, sold for 1 d at 20 ℃ after 16 d storage and stored for 4 d at 20 ℃ were 46, 3.2×103 and 3.1×104 cfu/g; during the test, salmonella and Listeria were not found; colibacillus in green pepper could be eliminated by 1×10-3 ml/L of chloros and most colibacillus in green pepper could be cleared away by 1 drop/L of detergent and running water. [Conclusion] Stored at 9 ℃, quality of green pepper could be better preserved and colibacillus propagation could be controlled.
基金Supported by the nature scientific fund of Heilongjiang province(No.110210).
文摘Production and storage-transportation of crude oil can not only give rise to soil pollution but also destroy ecological environment. Degradation of microbes for oily soil was studied with the instnunent, Geofina Hydrocarbon Meter (GHM), by experimental analysis qualitatively and quantitatively in the paper. Analytical result showed that the crude oil could be considerably degraded by eating-oil microbes in oily soil and the number of eating-oil microbes increased while the working hours of oil-well risi...
文摘Microbes were cultured from the samples at various depths in a weathering profile of RE-bearing granite in Gonghe RE mine, Guangdong Province. The cultured microbes, existing at a depth of 0.2 similar to 12 in and being more plentiful within 3 in in the profile, include bacteria ( Bacillus, Enterobacter, Escherichia, Alkaligenes, Neisseria, Staphylococcus and anaerobic bacteria such as Clostridium), fungi ( Aspergillus niger, Aspergillus flavus, Penicillium, Mucor and Saccharomycete) and actinomyces. Experiments were made under room temperature by using solutions of the cultured microbes and their metabolites, compared with distilled water and the culture solution without microbes, to leach RE from the sample of the weathering crust. The results are shown by the experiments: (1) The mixed microbes cultured from the profile and their metabolites increase the quantity of RE leached from the sample and reduce the pH of the solutions. (2) The ability to leach RE from the sample varies with various microbes, decreasing in a sequence of fungi ( Mucor, saccharomycete, Aspegillus and Penicillium), zymotic bacilli (Enterobacter, Escherichia etc.), Staphylococcus, zymotic Bacillus, actinomyces and Alkaligenes. (3) The RE leached with bacteria is mainly related to the pH value of the solutions influenced by the metabolites of the bacteria; whereas that leached with fungi is mainly related to the adsorption and imbibition of RE by the fungi and the complexing of RE with their metabolites. (4) Compared with that leached with ammonium sulfate, the fractionation of the RE leached with microbes is characterized by higher delta (Ce), lower delta (Eu) and lower ratios of N-La/Sm and N-Gd/Yb . The result of the fractionation of RE accords with the distribution of RE in the various layers of a profile of weathering crust of granite in South China. The experimental results indicate that microbes and their metabolites should play a positive role in the mobilization, migration and fractionation of RE in the weathering crust in South China.
基金the National Key Technology R&D Program of China (2006BAD05B06 and 2006BAD 02A14-13)
文摘The quantity of soil microbes and the structure of ammonium oxidizing bacterial (AOB) community were analyzed using the dilution plate counting and most probable number method (MPN), and denaturing gradient gel electrophoresis (DGGE), respectively. Fertilizer application tended to increase the number of soil microbes and alter the AOB community compared to the control with no fertilizer application (CK). Among the eight fertilizer treatments, soil samples from the treatments of mineral fertilizers (e.g., N, P, K) in combination with farmyard manure (M) had greater number.s of soil microbes and more complex structure of AOB community than those receiving mineral fertilizers alone. The principal component analyses (PCA) for ammonium oxidizing bacterial community structure showed that the eight fertilizer treatments could be divided into two PCA groups (PCA1 and PCA2). For the soil sampled after rice harvest, PCA1 included NP, NM, NPM and NPKM fertilizer treatments, while PCA2 was consisted of CK, N, M and NPK fertilizer treatments. For soil samples collected after wheat harvest, PCA1 was consisted of M, NM, NPM and NPKM fertilizer treatments, while PCA2 was composed of CK, N, NP and NPK fertilizer treatments. For a given rotation, the richness of AOB community in PCA1 was greater than that in PCA2. In addition, AOB community structure was more complex in the soil after rice harvest than that after wheat harvest. The results indicated that different fertilizer treatments resulted in substantial changes of soil microbe number and AOB community. Furthermore, mineral fertilizers (N, NP, NPK) combined with farmyard manure were effective for increasing the quantity of soil microbes, enriching AOB community, and improving the soil biofertility.
文摘Diversity analysis on secondary metabolites of Antarctic microbes, Rhodococcus sp. NJ-008 and Pseudomonas sp. NJ-011, together with the structural elucidation of some purified compounds, has been carried out for understanding of their chemical constituents. The methanol extracts of Rhodococcus sp. NJ-008 and Pseudomonas sp. NJ-011 were subjected to HPLC-TOF MS test for diversity analysis on secondary metabolites, respectively. The chemical constituents of NJ-011 are mainly N-containing compounds including some alkaloids and short polypeptides, while those of NJ-008 are not N-containing ones. Three compounds were also isolated and identified from extract of NJ011 by different column chromatography and preparative HPLC, and their structures were elucidated as b-carboline (1), 3-benzylhexahydropyrrolo[1,2-a]pyrazine-1,4-dione (2) and 3-isobutylhexahydropyrrolo[1,2-a]pyrazine-1,4-dione (3) by comparison of TOF MS, 1Hand 13C-NMR data with those reported. More microbial material of Pseudomonas sp. NJ-011 should be needed for exploration of the minor constituents with complicated structures.
文摘BOD measurements in presence of cobalt, nickel, copper, zinc, silver and cadmium are reported using wastewater from dairy industry as a seed. Extent of inhibition in BOD is studied for variables like, concen-tration of metal ions (0.2 mM to 1.4 mM), pH (3 to 8) and temperature of incubation (15℃, 20℃, 25℃, 30℃ and 35℃). Results of BOD inhibition are supported by absorbance measurement (OD600) studies of microbial matter preserved in Luriya broth medium. OD measurement results are used to derive minimum inhibitory concentration, i.e., threshold concentration of each metal showing toxicity towards microbes. Sil-ver is found to be the most toxic element.
基金Key Scientific Research Projects for Higher Education of Henan Province,Grant/Award Number:20A310012the College Student Innovation and Entrepreneurship Training Program of Henan Province,Grant/Award Number:202110472018 and S202110472046+1 种基金the Science and Technology Research Project of Henan Province,Grant/Award Number:192102310169 and 202102310270Doctoral Scientific Research Activation Foundation of the Xinxiang Medical University,Grant/Award Number:505287。
文摘Hypertension is an important global public health issue because of its high morbidity as well as the increased risk of other diseases.Recent studies have indicated that the development of hypertension is related to the dysbiosis of the gut microbiota in both animals and humans.In this review,we outline the interaction between gut microbiota and hypertension,including gut microbial changes in hypertension,the effect of microbial dysbiosis on blood pressure(BP),indicators of gut microbial dysbiosis in hypertension,and the microbial genera that affect BP at the taxonomic level.For example,increases in Lactobacillus,Roseburia,Coprococcus,Akkermansia,and Bifidobacterium are associated with reduced BP,while increases in Streptococcus,Blautia,and Prevotella are associated with elevated BP.Furthermore,we describe the potential mechanisms involved in the regulation between gut microbiota and hypertension.Finally,we summarize the commonly used treatments of hypertension that are based on gut microbes,including fecal microbiota transfer,probiotics and prebiotics,antibiotics,and dietary supplements.This review aims to find novel potential genera for improving hypertension and give a direction for future studies on gut microbiota in hypertension.
基金Foundation item: The China Ocean Mineral Resources Research and Development Association under contract No. DYXM-115-02-2-07the State Oceanic Administration of People’s Republic of China under contract No. 200805032the National Natural Science Foundation of China under contract Nos 50621063 and 40646029
文摘The aim of this study is to investigate microbial structures and diversities in five active hydrothermal fields' sediments along the Eastern Lau Spreading Centre (ELSC) in the Lau Basin (southwest Pacific). Microbial communities were surveyed by denatured gradient gel electrophoresis (DGGE) and clone library analysis of 16S rRNA genes. The differences in microbial community structures among sediment samples from the five deep-sea hydrothermal sites were revealed by DGGE profiles. Cluster analysis of DGGE profiles sepa- rated the five hydrothermal samples into two groups. Four different 16S rRNA gene clone libraries, repre- senting two selected hydrothermal samples (19-4TVG8 and 19-4TVG11), were constructed. Twenty-three and 32 phylotypes were identified from 166 and 160 bacterial clones respectively, including Proteobacteria, Bacteroidetes, Firmicutes, Nitrospirae and Planctomycetes. The phylum Proteobacteria is dominant in both bacterial libraries with a predominance of Gamma-Proteobacteria. A total of 31 and 25 phylotypes were obtained from 160 and 130 archaeal clones respectively, including Miscellaneous Crenarchaeotic Group, Marine Group Ⅰ and Ⅲ, Marine Benthic Group E, Terrestrial Hot Spring Crenarchaeota and Deep-sea Hy- drothermal Vent Euryarchaeota. These results show a variety of clones related to those involved in sulfur cycling, suggesting that the cycling and utilization of sulfur compounds may extensively occur in the Lau Basin deep-sea hydrothermal ecosystem.
基金funded by the Program of Department of Science and Technology,New Delhi,Government of India(No.IF110661)
文摘Bruguiera sexangula (Lout) Poir., a threatened mangrove tree, was inoculated with beneficial microbes in a nursery to assess any improvements in growth and bio- mass. From soil samples from the rhizosphere of B. sexangula in a mangrove forest in Panangadu of Kerala India, nitrogen-fixing bacteria Azotobacter chroococcum and Azospirillum brasilense were isolated. The phosphatesolubilising bacterium Bacillus megaterium and potassiummobilizing bacteria Frateruria aurantia were also isolated and cultured on suitable media. Later, ripe propagules of B. sexangula were collected from matured trees and raised in sterilized soil bags (13 × 25 cm) containing sterilized soil and sand (2:1 ratio). The cultured beneficial microbes were propagated and used to inoculate the ripe propagules of B. sexangula and maintained in the nursery for 6 months. After 6 months, growth and biomass of the inoculated propagules were greater than for the uninoculated control propagules. Shoot length, number of leaves, stem girth and root length were also significantly greater than in the controls. This study showed that the mangrove-specific beneficial microbes influenced the growth of B. sexangula
基金the National Natural Science Foundation of China (30671452).
文摘Earthworm and microbe are very important soil organisms. They play an important role in the stability of ecosystem and the bioavailability of nutrients and heavy metals in soils. This article reviewed the function of earthworm and microbes in improving soil structure and controlling soil nutrients as well as their effects on the bioavailability of heavy metals in soil through bioabsorption, enrichment, precipitation, dissolution, and oxidation-reduction. The aim is to provide a certain theoretical basis for modern agricultural production.
文摘A pot culture experiment was carried out in a glasshouse to compare the physiology and growth of sweet corn plants (Zea mays L. cv. Honey Bantam) grown under organic and chemical fertilizations with or without microbial inoculation (MI). The organic fertilizer used was fermented mainly using rice bran and oil mill sludge, and the MI was a liquid product containing many beneficial microbes such as lactic acid bacteria, yeast, photosynthetic bacteria and actinomycetes. The application amounts of the organic fertilizer and chemical fertilizers were based on the same rate of nitrogen, phosphorus and potassium. Sweet corn plants fertilized with organic materials inoculated with beneficial microbes grew better than those without inoculation. There were no significant differences in physiology and growth of the sweet corn plants between treatments of chemical fertilizers with and without MI. Among the organic fertilization treatments, only the sweet corn plants with organic fertilizer and MI applied 4 weeks before sowing had similar photosynthetic capacityj total dry matter yield and ear yield to those with chemical fertilizers. Sweet corn plants in other organic fertilization treatments were weaker in physiology and growth than those in chemical fertilization treatments. There was no significant variance among chemical fertilization treatments at different time. It is concluded from this research that this organic fertilizer would be more effective if it was inoculated with the beneficial microbes. Early application of the organic fertilizer with beneficial microbes before sowing was recommended to make the nutrients available before the rapid growth at the early stage and obtain a yield similar to or higher than that with chemical fertilizations.
基金Supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA11030404)the Guangzhou Science and Technology Plan Projects(No.201510010012)the National Natural Science Foundation of China(No.21302199)
文摘A novel esterase EstC10 from Bacillus sp. CX01 isolated from the deep sea of the Western Pacific Ocean and the functionalities of EstC 10 was characterized. At present, the reports about the kinetic resolution ofracemic methyl 2-chloropropionate were quite rare. So we developed deep-sea microbial esterase EstC10 as a novel biocatalyst in the kinetic resolution of racemic methyl 2-chloropropionate and generate (R)-methyl 2-chloropropionate with high enantiomeric excess (〉99%) after the optimization of process parameters such as pH, temperature, organic co-solvents, surfactants, substrate concentration and reaction time. Notably, the optimal substrate concentration (80 mmol/L) of esterase EstC10 was higher than the kinetic resolution of another esterase, Estl2-7 (50 mmoFL). The novel microbial esterase EstC10 identified from the deep sea was a promising green biocatalyst in the generation of (R)-methyl 2-chloropropionate as well of many other valuable chiral chemicals in industry.
文摘Laboratory and in situ experiments were done to investigate the influences of cultivation on temperate semi arid grassland (for 17 years spring wheat planted once every two years without fertilization) on soil N 2O emission and quantitative variations of related soil microbes. In the laboratory (25℃ and soil moisture 18%), cultivation increased soil transformations of fertilizer nitrogen (100 μg N/g as NaNO 3, urea, or as urea with dicyandiamide 1 μg N/g). The N 2O emissions from the cultivated and uncultivated soils with or without nitrogen additions were relatively low, and mainly originated from the nitrification. The soil N 2O emission due to cultivation decreased somewhat upon no fertilization or NaNO 3 addition, but significantly upon urea addition. The role of dicyandiamide as nitrification inhibitor was only considerable in the cultivated soil, and had small influence on decreasing N 2O emission in the two soils. The influence of cultivation on soil N 2O emission was also reflected by the number variations of microbes related with soil nitrogen transformation in the two soils. Compared to the uncultivated grassland, in situ ammonifiers and denitrifiers in the cultivated grassland quantitatively averagely increased, and aerobic no symbiotic azotobacters were quantitatively similar, leading to the continued decrease of organic matter content and the decrease of N 2O emission from the cultivated grassland soil.