The action of etching and damage by 20 keV N+ beam on the cells of Deinococcus radiodurans and Escherichia coli was investigated by scanning electron microscope (SEM) and the electron spin resonance (ESR) spectrum of ...The action of etching and damage by 20 keV N+ beam on the cells of Deinococcus radiodurans and Escherichia coli was investigated by scanning electron microscope (SEM) and the electron spin resonance (ESR) spectrum of free radicals. The results showed that N+ implantation exerted the direct action of etching and damage of momentum transferring and the indirect action of the free radicals of energy deposition on their cells, many microholes were found on the surface of cells' wall and /or membrane by SEM, the damaged DNA was determined using DNA unwinding technique, and the signal of free radicals was measured by ESR. The degree of damage to cells by ion beam gradually increased with the increase implantation dose. With the post-treatment of 2 mmol/l caffeine and 0.5 mmol / l Na2-EDTA, the survival rate of D.radiodurans and E.coli further decreased in the order of caffeine > Na2-EDTA > control, and this suggested that low energy ion beam could be implanted into nucleus, doing a damage to DNA and resulting in the mutation of organisms.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
The multifunctionality and the advantages of thermal plasma for the fast inactivation of viable cells and degradation of organic compounds dissolved in waste water are presented.A complete bacterial inactivation proce...The multifunctionality and the advantages of thermal plasma for the fast inactivation of viable cells and degradation of organic compounds dissolved in waste water are presented.A complete bacterial inactivation process was observed and studied using a thermal plasma treatment source with very short application times,in particular for Staphylococcus aureus bundle spore survival.The survival curves and analyses of the experimental data of the initial and final densities of S.aureus bacteria show a dramatic inhibitory effect of the plasma discharge on the residual bacteria survival ratio.As the exposure time increased,the inactivation process rate increased for direct exposure more than it did for indirect exposure.The evaluation of direct and indirect exposure was based on the analysis of the ultraviolet spectrum from the absorbance spectra of the organic compound dye called benzene sulfonate（C（16）H（11）N2Na O4S）and of viable cells called S.aureus.Organic compounds were degraded and viable cells were killed in a short time by thermal plasma.Moreover,analyses of total carbon,total organic carbon,and total inorganic carbon showed a fast decrease in organically bound carbon,however,this was not as fast as the absorbance spectra revealed by the exposure time increasing more for direct exposure than indirect exposure.After 100 s of exposure to the organic compound dye the removal had a maximun of 40%for samples with indirect exposure to the plasma and a maximum of 90%for samples with the direct exposure.For both samples,where some organic contaminants still remained in treated water,four electrolytes（KCl,Na Cl,Na2SO4,and CH3COONa）were added to be effective for complete sterilization,reaching a purity of 100%.A proposal is made for an optimized thermal plasma water purification system（TPWPS）to improve fast inactivation of microbes and the degradation of organic compounds dissolved in water（especially for direct exposure rather than indirect exposure）using a hybrid plasma torch with an electrical power of 125 kW（500 V–250 A）producing a high-temperature（10 000 K–19 000 K）plasma jet with a maximum gas consumption of 28 mg s^-1.展开更多
Microbes are microscopic living organisms that surround us which include bacteria, archaea, most protozoa, and some fungi and algae. In recent years, microbes have been explored as novel precursors to synthesize carbo...Microbes are microscopic living organisms that surround us which include bacteria, archaea, most protozoa, and some fungi and algae. In recent years, microbes have been explored as novel precursors to synthesize carbon-based（nano）materials and as substrates or templates to produce carbon-containing（nano）composites. Being greener and more affordable, microbe-derived carbons（MDCs） offer good potential for energy applications. In this review, we describe the unique advantages of MDCs and outline the common procedures to prepare them. We also extensively discuss the energy applications of MDCs including their use as electrodes in supercapacitors and lithium-ion batteries, and as electrocatalysts for processes such as oxygen reduction, oxygen evolution, and hydrogen evolution reactions which are essential for fuel cell and water electrochemical splitting cells. Based on the literature trend and our group＇s expertise, we propose potential research directions for developing new types of MDCs. This review, therefore, provides the state-of-the-art of a new energy chemistry concept. We expect to stimulate future research on the applications of MDCs that may address energy and environmental challenges that our societies are facing.展开更多
Many studies have revealed that gut microbes modulate host metabolism.In this study,we characterized the therapeutic effects of a novel gut commensal Luoshenia tenuis against host metabolic disorders.First,by in silic...Many studies have revealed that gut microbes modulate host metabolism.In this study,we characterized the therapeutic effects of a novel gut commensal Luoshenia tenuis against host metabolic disorders.First,by in silico analysis,we demonstrated that the L.tenuis was prevalent in the gut microbiomes of healthy humans but were depleted specifically in obesity cohorts.Further in vitro cultivation revealed that L.tenuis produced short chain fatty acids that were verified to modulate host metabolism and some other volatile metabolites to benefit hosts by anti-inflammation and anti-tumor.Second,gavage of the L.tenuis significantly decreased the body weight gain and food intake of high-fat diet-feeding C57BL/6J mice,which was in parallel with the changed expression level of genes related to satiety and feeding behavior.We then performed the gavage trial using diet induced obese mice,and it revealed that the administration of L.tenuis alleviated significantly the abnormal glucose and lipid metabolisms and reduced the inflammatory response.In summary,this study revealed a previously-unknown human gut commensal microbe that benefited host metabolism,and set the stage for the development of novel next-generation probiotic applicable for treatment of obesity and related metabolic disorders.展开更多
This paper describes the experience of Jilin oilfield trials for Microbial Enhanced Oil Recovery (MEOR). A new technique to identify microbes with DNA for MEOR has been established, and useful microbes selected f...This paper describes the experience of Jilin oilfield trials for Microbial Enhanced Oil Recovery (MEOR). A new technique to identify microbes with DNA for MEOR has been established, and useful microbes selected for use in field trials. Behaviors of bacteria activated in the reservoir, oil recovery and water cut, and the viscosity of crude oil produced through huff & puff testing and flooding with molasses-injection tests, have been investigated in situ. CJF-002, which produces biopolysaccharide, is the best among the microbes used for field trials, as it can use molasses as nutrient and produce a small quantity of CO2 and a mass of water-insoluble biopolymer. The metabolic behavior in the reservoir showed that CJF-002 had a good potentiality for MEOR.展开更多
Soil microbes may be critical players in determining the allelopathic potential of some plants. Low levels of plant community biodiversity in Eucalyptus plantations have been attributed to the allelopathic potential o...Soil microbes may be critical players in determining the allelopathic potential of some plants. Low levels of plant community biodiversity in Eucalyptus plantations have been attributed to the allelopathic potential of these tree species. The role of soil microbes in the allelopathic effect of leaf leachates of the hybrid tree Eucalyptus grandis x E. urophylla, was tested in Petri dish assays with Brassica chinensis as a receiver plant. Soils were collected from either a local garden (soil A) or a Eucalyptus plantation (soil B) and half of each soil was sterilized to remove microbes. These soils were then treated with E. grandis x E. urophylla leachates for 0-72 h. Seed germination of B. chinensis was significantly inhibited in soils treated with leaf leachates relative to untreated soils. The inhibitory effect of the leaf leachates was more pronounced in sterilized soils. Total phenolic content was obvious lower in nonsterile leachate-treated soils than in sterile soils. Biomass of B. chinensis was negatively correlated with the total phenolic content in soils. Our findings suggest that soil microbes can alleviate the allelopathic potential of Eucalyptus and thereby its negative impact on plant growth.展开更多
The powdered activated carbon treatment(PACT) process has been widely used in many industrial fields, however,very few PACT processes are built for petrochemical wastewater treatment in China. An industrial PACT unit ...The powdered activated carbon treatment(PACT) process has been widely used in many industrial fields, however,very few PACT processes are built for petrochemical wastewater treatment in China. An industrial PACT unit launched in a petrochemical plant was introduced and evaluated from both the practice and mechanism study. Practically, the PACT process showed excellent capability in pollutants removal, shock resistance, toxicity tolerance, and the COD and ammoniumN in effluent of PACT unit assisted by PAC was equal to 15.5 mg/L and 0.7 mg/L lower than that without PAC addition,respectively. The wet oxidation regeneration unit was quite efficient in supplying regenerated PAC, and, however, the hard calcium sulphate scale and the high pollutant concentration solution needed to be carefully controlled. Moreover, although the carbon balance showed that the adsorption capability of regenerated PAC was negligible, the biological tests proved that the regenerated PAC increased microbe activity up to 17% more than pure activated sludge system, which was almost compatible with the fresh activated carbon.展开更多
We investigated the Effects of plantation development, seasons, and soil depth on soil microbial indices in Gmelina arborea plantations in south-western Nigeria. Soil samples were obtained from the soil depths of 0-15...We investigated the Effects of plantation development, seasons, and soil depth on soil microbial indices in Gmelina arborea plantations in south-western Nigeria. Soil samples were obtained from the soil depths of 0-15 and 15-30 cm from plantations of six different ages during the rainy season, dry seasons, and their transitions. We used plate count and fumigation-extraction methods to determine microbe population and microbial biomass carbon （MB-C） and nitrogen （MB-N）, respectively. Plantation age did not affect microbial indices, implying a non-significant effect of plantation development on microbial communities. It could also imply that soil microbial indices had already stabilized in the sampled plantations. Seasonal variation and soil depth had significant effects on microbial indices. At 0-15 cm soil depth, mean MB-C increased from 50.74 μg·g^-1 during the peak of the dry season （i.e. March） to 99.58μg·g-1 during the peak of the rainy season （i.e. September）, while it increased from 36.22μg·.g^-1 to 75.31μg·.g^-1 at 15-30 cm soil depth between the same seasonal periods. Bacteria populations and MB-N showed similar increasing trends. Correlations between MB-C, MB-N, microbe populations, and rainfall were positive and linear. Significantly higher microbial activities took place in the plantations during the rainy season, increased with soil wetness, and decreased at greater soil depth.展开更多
The microbial population in rotten living body of Salix matsudana caused by Trametes suaveolens (L.) was researched. 11 bacteria species (1 species of Bacillus, 2 species of Clostridium and 8 species of non-brood-cell...The microbial population in rotten living body of Salix matsudana caused by Trametes suaveolens (L.) was researched. 11 bacteria species (1 species of Bacillus, 2 species of Clostridium and 8 species of non-brood-cell bacteria), 1 species of Actinomyces that belongs to Lavendulac, 8 species of fungi and 6 species of Trichoderma were isolated from rotten trunk. The hyphae of Trametes suaveolens mainly existed between rotten sections and discoioration sections. In over-rotten section and healthy section the fungi (Trametes suaveolens) were not isolated. The microbes that lived in the discoloration section were the most in kinds and number and they were the pioneer microbes of wood rotting. Only after they dwelled in wood and eIiminated its rot-resistance,could wood-rotting fungi invade wood and caused wood-rotting.展开更多
Dendroremediation,a novel strategy for cleaning up contaminants from the environment by using special woody plant species and microbes,is a popular phytoremediation approach.It is a cost-effective and environmentally ...Dendroremediation,a novel strategy for cleaning up contaminants from the environment by using special woody plant species and microbes,is a popular phytoremediation approach.It is a cost-effective and environmentally friendly method that is being increasingly adopted.Poplar species(Populus L.)have been suggested for use in remediation because of their characteristics of high biomass production,fast growth,and potential for removing pollutants.Our environment is often contaminated by toxic substances produced by human activities,and remediation of contamination is therefore a global issue.Atrazine is one of the most widely used herbicides in China.In the present study,‘I-69/55’poplar(P.deltoides cv.‘I-69/55’)and hybrid poplar(Populus deltoides×nigra,DN34)grown in pots were assayed for their ability to remediate atrazine-contaminated soils.The degradation dynamics of atrazine were assessed with a high-performance liquid chromatography system using materials from a greenhouse with different rhizosphere environments.We studied the dynamic variation in microbes and microbial biomass carbon to elucidate the rhizosphere effects and mechanism of remediation of atrazine-contaminated soil by poplar.Our four treatments included a control with uncontaminated soil without a tree,atrazine pollution without a tree,atrazine pollution with‘I-69/55’poplar,and atrazine pollution with hybrid poplar.Hybrid poplar showed potential for remediation of atrazine-contaminated soil,and the degradation of atrazine in the rhizosphere was faster than that in non-rhizosphere soil.Atrazine significantly inhibited bacteria growth in nonrhizosphere soil.The high concentration of bacteria in the hybrid poplar rhizosphere might be key to atrazine degradation.Trends of change among fungi and actinomyces did not correspond to trends in atrazine degradation throughout the trial period.Further research is needed to predict the effects of atrazine on cultivable microorganisms in various soils.Atrazine had significant inhibitory effects on microbial biomass carbon in non-rhizosphere soil,and the rhizosphere environment of poplars enhanced the recovery of microbial biomass carbon.The potential for hybrid poplar as a dendroremediation material needs further study.展开更多
Objective Pesticides has gain an increasing awareness because of it is becoming a serious environmental problem and come to threaten the health of humanbeing.The effect of five pesticides(zineb,copforce,the mixture of...Objective Pesticides has gain an increasing awareness because of it is becoming a serious environmental problem and come to threaten the health of humanbeing.The effect of five pesticides(zineb,copforce,the mixture of carbendazim and mancozeb,hymexazol)on soil bacteria,fungi,actinomyces,and Five specific enzymes were chosen for investigation(urease,dehydrogenase,invertase,acid phosphates and protease).Methods The enumeration of the soil micro flora was done by the dilution plate method;The enzyme activity was determined by traditional methods.Shannon-Wiener index as well as 16S rRNA-PCR amplification and DGGE fingerprinting was used for detection of shift in microbial community diversity in pesticides contaminated agricultural soil.Results The outcome showed that the microbial diversity was significantly changed after the application of pesticides,the effect of pesticides on microbe had a order from top to bottom:bacteria-actinomyces-fungi.Conclusions Our results indicate that the use of the pesticides hymexazol resulted in an altered soil community structure,in particular for the actinomyces.Invertase was markedly inhibited by hymexazol,zineb,carbendazim and mancozeb and the inhibiting rates were varied between 30.30% and 21.21%;Urease activity was also inhibited significantly by hymexazol,the inhibiting rate was 37.67%;Protease activity was markedly inhibited by zineb and hymexazol,the inhibiting rates were 27.27% and 18.18% respectively;Phosphates activity was inhibited significantly by hymexazol,zineb,carbendazim and mancozeb,the inhibiting rates were range from 22.12%-3.54%;Dehydrogenase activity was not significantly affected by pesticides.Meanwhile,the correlation of all indexes were analyzed,the data suggested that all indexes existed certain correlation.展开更多
Root-associated microbes play an essentialrole in mediating plant growth,health,and habitat adaptability.However,it is unknown which microbial taxa help develop host fitness and how habitats shape root-associated micr...Root-associated microbes play an essentialrole in mediating plant growth,health,and habitat adaptability.However,it is unknown which microbial taxa help develop host fitness and how habitats shape root-associated microbial assembly patterns.As an endemic species of subalpine forests in western Sichuan,China,Minjiang fir(Abies fargesii var.faxoniana)is dominant on cold-shaded northwestern slopes while absent on warm sunlit southwestern slopes.In this study,fungal and bacterial communities were investigated in three spatial compartments(endosphere,rhizosphere,and bulk soil)associated with Minjiang fir saplings on a cold-shaded northwestern slope and a warm sunlit southwestern slope.Habitats differentiated the microbial communities regardless of the spatial compartment and microbial taxa.Slope aspect variations caused shifts in root-associated(rhizosphere and endosphere)microbial compositions.Compared with the southwestern slope,the cold-shaded northwestern slope harbored a higher abundance of the growth-promoting bacteria Burkholderia and ectomycorrhizal fungi Cortinarius and Piloderma.The slope aspect had stronger effects on fungal diversity than bacterial diversity,with higher fungal endemism and lower bacterial endemism.Slope aspect variations were the dominant drivers of root-associated microbial communities,with lower contribution by soil properties and higher contribution by plant traits on the northwestern slope.Findings from this study could improve the understanding of plant habitat adaptability from the perspective of microbial community assembly.It is suggested that forest management should consider root-associated microbiomes for enhancing species fitness and habitat adaptability.展开更多
Ticks transmit a diverse array of microbes to vertebrate hosts,including human pathogens,which has led to a human-centric focus in this vector system.Far less is known about pathogens of ticks themselves.Here,we disco...Ticks transmit a diverse array of microbes to vertebrate hosts,including human pathogens,which has led to a human-centric focus in this vector system.Far less is known about pathogens of ticks themselves.Here,we discover that a toxin in blacklegged ticks(Ixodes scapularis)horizontally acquired from bacteria-called domesticated amidase effector 2(dae2)-has evolved to kill mammalian skin microbes with remarkable efficiency.Secreted into the saliva and gut of ticks,Dae2 limits skin-associated staphylococci in ticks while feeding.In contrast,Dae2 has no intrinsic ability to kill Borrelia burgdorferi,the tick-borne Lyme disease bacterial pathogen.These findings suggest ticks resist their own pathogens while tolerating symbionts.Thus,just as tick symbionts can be pathogenic to humans,mammalian commensals can be harmful to ticks.Our study underscores how virulence is context-dependent and bolsters the idea that"pathogen"is a status and not an identity.展开更多
Stability, boundedness and persistence are three important aspects for an ecological model. In this paper, a further analysis of a class of anaerobic digestion ecological models is performed. Based on the Liupunov Met...Stability, boundedness and persistence are three important aspects for an ecological model. In this paper, a further analysis of a class of anaerobic digestion ecological models is performed. Based on the Liupunov Method, the local stability of all equilibria in the system is got. According to the vector fields described by the system, the proof of the boundedness of the solution on the anaerobic digestion processes is completed in three steps. The method proposed in the discussion on the boundedness can be generalized to the similar problems. Results in this paper give information on how to run the ecological system well by adjusting the system parameters.展开更多
Pu-erh tea has been shown to reduce gut inflammation in dextran sulfate sodium(DSS)-induced mice.Also,we found abnormal liver cholesterol metabolism in DSS-induced mice.However,it's not clear how Pu-erh tea improv...Pu-erh tea has been shown to reduce gut inflammation in dextran sulfate sodium(DSS)-induced mice.Also,we found abnormal liver cholesterol metabolism in DSS-induced mice.However,it's not clear how Pu-erh tea improves DSS-induced impaired liver cholesterol metabolism.Here,we established the DSS-induced model and clarified that DSS exacerbated gut inflammation accompanied by disorders of liver cholesterol metabolism.Pu-erh tea reshaped gut microbes,limited gut oxidative stress and inflammation(nicotinamide adenine dinucleotide phosphate oxidase 2/reactive oxygen species/myeloid differentiation primary response protein 88/nuclear factor kappa-B,24.97%-52.89%),reduced gut bile acid reabsorption(up-regulation of farnesoid X receptor(FXR)/fibroblast growth factor 15,24.53%-55.91%),and promoted liver bile acid synthesis(up-regulation of peroxisome proliferator-activated receptor-α/cholesterol 7-alpha hydroxylase,34.65%-79.14%),thereby partly restoring liver cholesterol metabolism(regulated FXR/small heterodimer partner/sterol-regulatory element binding proteins,53.19%-95.40%).Altered bile acid metabolic profiles(increased chenodeoxycholic acid,ursodeoxycholic acid,lithocholic acid,etc.)may also improve liver cholesterol metabolism by altering gut and liver inflammation.Thus,gut microbial reshaping and altered bile acid metabolism may be key targets of Pu-erh tea for improving DSS-induced liver cholesterol metabolism disorders via the gut-gut microbe-bile acid-liver axis.展开更多
基金This work is supported by the National Science Foundation of china (19605005)
文摘The action of etching and damage by 20 keV N+ beam on the cells of Deinococcus radiodurans and Escherichia coli was investigated by scanning electron microscope (SEM) and the electron spin resonance (ESR) spectrum of free radicals. The results showed that N+ implantation exerted the direct action of etching and damage of momentum transferring and the indirect action of the free radicals of energy deposition on their cells, many microholes were found on the surface of cells' wall and /or membrane by SEM, the damaged DNA was determined using DNA unwinding technique, and the signal of free radicals was measured by ESR. The degree of damage to cells by ion beam gradually increased with the increase implantation dose. With the post-treatment of 2 mmol/l caffeine and 0.5 mmol / l Na2-EDTA, the survival rate of D.radiodurans and E.coli further decreased in the order of caffeine > Na2-EDTA > control, and this suggested that low energy ion beam could be implanted into nucleus, doing a damage to DNA and resulting in the mutation of organisms.
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financial support from MEPhI in the framework of the Russian Academic Excellence Project
文摘The multifunctionality and the advantages of thermal plasma for the fast inactivation of viable cells and degradation of organic compounds dissolved in waste water are presented.A complete bacterial inactivation process was observed and studied using a thermal plasma treatment source with very short application times,in particular for Staphylococcus aureus bundle spore survival.The survival curves and analyses of the experimental data of the initial and final densities of S.aureus bacteria show a dramatic inhibitory effect of the plasma discharge on the residual bacteria survival ratio.As the exposure time increased,the inactivation process rate increased for direct exposure more than it did for indirect exposure.The evaluation of direct and indirect exposure was based on the analysis of the ultraviolet spectrum from the absorbance spectra of the organic compound dye called benzene sulfonate（C（16）H（11）N2Na O4S）and of viable cells called S.aureus.Organic compounds were degraded and viable cells were killed in a short time by thermal plasma.Moreover,analyses of total carbon,total organic carbon,and total inorganic carbon showed a fast decrease in organically bound carbon,however,this was not as fast as the absorbance spectra revealed by the exposure time increasing more for direct exposure than indirect exposure.After 100 s of exposure to the organic compound dye the removal had a maximun of 40%for samples with indirect exposure to the plasma and a maximum of 90%for samples with the direct exposure.For both samples,where some organic contaminants still remained in treated water,four electrolytes（KCl,Na Cl,Na2SO4,and CH3COONa）were added to be effective for complete sterilization,reaching a purity of 100%.A proposal is made for an optimized thermal plasma water purification system（TPWPS）to improve fast inactivation of microbes and the degradation of organic compounds dissolved in water（especially for direct exposure rather than indirect exposure）using a hybrid plasma torch with an electrical power of 125 kW（500 V–250 A）producing a high-temperature（10 000 K–19 000 K）plasma jet with a maximum gas consumption of 28 mg s^-1.
基金supported by the Ministry of Education, Singapore (2013-T1-002132)the iFood program of Nanyang Technological UniversityThe University of Sydney for financial support
文摘Microbes are microscopic living organisms that surround us which include bacteria, archaea, most protozoa, and some fungi and algae. In recent years, microbes have been explored as novel precursors to synthesize carbon-based（nano）materials and as substrates or templates to produce carbon-containing（nano）composites. Being greener and more affordable, microbe-derived carbons（MDCs） offer good potential for energy applications. In this review, we describe the unique advantages of MDCs and outline the common procedures to prepare them. We also extensively discuss the energy applications of MDCs including their use as electrodes in supercapacitors and lithium-ion batteries, and as electrocatalysts for processes such as oxygen reduction, oxygen evolution, and hydrogen evolution reactions which are essential for fuel cell and water electrochemical splitting cells. Based on the literature trend and our group＇s expertise, we propose potential research directions for developing new types of MDCs. This review, therefore, provides the state-of-the-art of a new energy chemistry concept. We expect to stimulate future research on the applications of MDCs that may address energy and environmental challenges that our societies are facing.
基金financially supported by the National Key Research and Development Program of China(2021YFA0717002)。
文摘Many studies have revealed that gut microbes modulate host metabolism.In this study,we characterized the therapeutic effects of a novel gut commensal Luoshenia tenuis against host metabolic disorders.First,by in silico analysis,we demonstrated that the L.tenuis was prevalent in the gut microbiomes of healthy humans but were depleted specifically in obesity cohorts.Further in vitro cultivation revealed that L.tenuis produced short chain fatty acids that were verified to modulate host metabolism and some other volatile metabolites to benefit hosts by anti-inflammation and anti-tumor.Second,gavage of the L.tenuis significantly decreased the body weight gain and food intake of high-fat diet-feeding C57BL/6J mice,which was in parallel with the changed expression level of genes related to satiety and feeding behavior.We then performed the gavage trial using diet induced obese mice,and it revealed that the administration of L.tenuis alleviated significantly the abnormal glucose and lipid metabolisms and reduced the inflammatory response.In summary,this study revealed a previously-unknown human gut commensal microbe that benefited host metabolism,and set the stage for the development of novel next-generation probiotic applicable for treatment of obesity and related metabolic disorders.
文摘This paper describes the experience of Jilin oilfield trials for Microbial Enhanced Oil Recovery (MEOR). A new technique to identify microbes with DNA for MEOR has been established, and useful microbes selected for use in field trials. Behaviors of bacteria activated in the reservoir, oil recovery and water cut, and the viscosity of crude oil produced through huff & puff testing and flooding with molasses-injection tests, have been investigated in situ. CJF-002, which produces biopolysaccharide, is the best among the microbes used for field trials, as it can use molasses as nutrient and produce a small quantity of CO2 and a mass of water-insoluble biopolymer. The metabolic behavior in the reservoir showed that CJF-002 had a good potentiality for MEOR.
基金supported by the Sci-technology program of Guangxi Province(No.Guikezhong 1347001)
文摘Soil microbes may be critical players in determining the allelopathic potential of some plants. Low levels of plant community biodiversity in Eucalyptus plantations have been attributed to the allelopathic potential of these tree species. The role of soil microbes in the allelopathic effect of leaf leachates of the hybrid tree Eucalyptus grandis x E. urophylla, was tested in Petri dish assays with Brassica chinensis as a receiver plant. Soils were collected from either a local garden (soil A) or a Eucalyptus plantation (soil B) and half of each soil was sterilized to remove microbes. These soils were then treated with E. grandis x E. urophylla leachates for 0-72 h. Seed germination of B. chinensis was significantly inhibited in soils treated with leaf leachates relative to untreated soils. The inhibitory effect of the leaf leachates was more pronounced in sterilized soils. Total phenolic content was obvious lower in nonsterile leachate-treated soils than in sterile soils. Biomass of B. chinensis was negatively correlated with the total phenolic content in soils. Our findings suggest that soil microbes can alleviate the allelopathic potential of Eucalyptus and thereby its negative impact on plant growth.
基金financially supported by SINOPEC (CLY15043)CRICC of ChemChina (2017-KZY03 and 2018-KZ-Y04)
文摘The powdered activated carbon treatment(PACT) process has been widely used in many industrial fields, however,very few PACT processes are built for petrochemical wastewater treatment in China. An industrial PACT unit launched in a petrochemical plant was introduced and evaluated from both the practice and mechanism study. Practically, the PACT process showed excellent capability in pollutants removal, shock resistance, toxicity tolerance, and the COD and ammoniumN in effluent of PACT unit assisted by PAC was equal to 15.5 mg/L and 0.7 mg/L lower than that without PAC addition,respectively. The wet oxidation regeneration unit was quite efficient in supplying regenerated PAC, and, however, the hard calcium sulphate scale and the high pollutant concentration solution needed to be carefully controlled. Moreover, although the carbon balance showed that the adsorption capability of regenerated PAC was negligible, the biological tests proved that the regenerated PAC increased microbe activity up to 17% more than pure activated sludge system, which was almost compatible with the fresh activated carbon.
文摘We investigated the Effects of plantation development, seasons, and soil depth on soil microbial indices in Gmelina arborea plantations in south-western Nigeria. Soil samples were obtained from the soil depths of 0-15 and 15-30 cm from plantations of six different ages during the rainy season, dry seasons, and their transitions. We used plate count and fumigation-extraction methods to determine microbe population and microbial biomass carbon （MB-C） and nitrogen （MB-N）, respectively. Plantation age did not affect microbial indices, implying a non-significant effect of plantation development on microbial communities. It could also imply that soil microbial indices had already stabilized in the sampled plantations. Seasonal variation and soil depth had significant effects on microbial indices. At 0-15 cm soil depth, mean MB-C increased from 50.74 μg·g^-1 during the peak of the dry season （i.e. March） to 99.58μg·g-1 during the peak of the rainy season （i.e. September）, while it increased from 36.22μg·.g^-1 to 75.31μg·.g^-1 at 15-30 cm soil depth between the same seasonal periods. Bacteria populations and MB-N showed similar increasing trends. Correlations between MB-C, MB-N, microbe populations, and rainfall were positive and linear. Significantly higher microbial activities took place in the plantations during the rainy season, increased with soil wetness, and decreased at greater soil depth.
文摘The microbial population in rotten living body of Salix matsudana caused by Trametes suaveolens (L.) was researched. 11 bacteria species (1 species of Bacillus, 2 species of Clostridium and 8 species of non-brood-cell bacteria), 1 species of Actinomyces that belongs to Lavendulac, 8 species of fungi and 6 species of Trichoderma were isolated from rotten trunk. The hyphae of Trametes suaveolens mainly existed between rotten sections and discoioration sections. In over-rotten section and healthy section the fungi (Trametes suaveolens) were not isolated. The microbes that lived in the discoloration section were the most in kinds and number and they were the pioneer microbes of wood rotting. Only after they dwelled in wood and eIiminated its rot-resistance,could wood-rotting fungi invade wood and caused wood-rotting.
基金supported by the Central Non-profit Research Institution of Chinese Academy of Forestry(CAFYBB2017MA027,CAFYBB2014QB046)the Overseas Outstanding Scholars Lecture Program+2 种基金the Fundamental Research Funds for the Central Non-profit Research Institution of CAF(CAFYBB2017ZF005)the National Natural Science Foundation of China(Nos.30700637,31460133)‘‘948’’ Project(No.2013-4-80)
文摘Dendroremediation,a novel strategy for cleaning up contaminants from the environment by using special woody plant species and microbes,is a popular phytoremediation approach.It is a cost-effective and environmentally friendly method that is being increasingly adopted.Poplar species(Populus L.)have been suggested for use in remediation because of their characteristics of high biomass production,fast growth,and potential for removing pollutants.Our environment is often contaminated by toxic substances produced by human activities,and remediation of contamination is therefore a global issue.Atrazine is one of the most widely used herbicides in China.In the present study,‘I-69/55’poplar(P.deltoides cv.‘I-69/55’)and hybrid poplar(Populus deltoides×nigra,DN34)grown in pots were assayed for their ability to remediate atrazine-contaminated soils.The degradation dynamics of atrazine were assessed with a high-performance liquid chromatography system using materials from a greenhouse with different rhizosphere environments.We studied the dynamic variation in microbes and microbial biomass carbon to elucidate the rhizosphere effects and mechanism of remediation of atrazine-contaminated soil by poplar.Our four treatments included a control with uncontaminated soil without a tree,atrazine pollution without a tree,atrazine pollution with‘I-69/55’poplar,and atrazine pollution with hybrid poplar.Hybrid poplar showed potential for remediation of atrazine-contaminated soil,and the degradation of atrazine in the rhizosphere was faster than that in non-rhizosphere soil.Atrazine significantly inhibited bacteria growth in nonrhizosphere soil.The high concentration of bacteria in the hybrid poplar rhizosphere might be key to atrazine degradation.Trends of change among fungi and actinomyces did not correspond to trends in atrazine degradation throughout the trial period.Further research is needed to predict the effects of atrazine on cultivable microorganisms in various soils.Atrazine had significant inhibitory effects on microbial biomass carbon in non-rhizosphere soil,and the rhizosphere environment of poplars enhanced the recovery of microbial biomass carbon.The potential for hybrid poplar as a dendroremediation material needs further study.
文摘Objective Pesticides has gain an increasing awareness because of it is becoming a serious environmental problem and come to threaten the health of humanbeing.The effect of five pesticides(zineb,copforce,the mixture of carbendazim and mancozeb,hymexazol)on soil bacteria,fungi,actinomyces,and Five specific enzymes were chosen for investigation(urease,dehydrogenase,invertase,acid phosphates and protease).Methods The enumeration of the soil micro flora was done by the dilution plate method;The enzyme activity was determined by traditional methods.Shannon-Wiener index as well as 16S rRNA-PCR amplification and DGGE fingerprinting was used for detection of shift in microbial community diversity in pesticides contaminated agricultural soil.Results The outcome showed that the microbial diversity was significantly changed after the application of pesticides,the effect of pesticides on microbe had a order from top to bottom:bacteria-actinomyces-fungi.Conclusions Our results indicate that the use of the pesticides hymexazol resulted in an altered soil community structure,in particular for the actinomyces.Invertase was markedly inhibited by hymexazol,zineb,carbendazim and mancozeb and the inhibiting rates were varied between 30.30% and 21.21%;Urease activity was also inhibited significantly by hymexazol,the inhibiting rate was 37.67%;Protease activity was markedly inhibited by zineb and hymexazol,the inhibiting rates were 27.27% and 18.18% respectively;Phosphates activity was inhibited significantly by hymexazol,zineb,carbendazim and mancozeb,the inhibiting rates were range from 22.12%-3.54%;Dehydrogenase activity was not significantly affected by pesticides.Meanwhile,the correlation of all indexes were analyzed,the data suggested that all indexes existed certain correlation.
基金jointly funded by the National Key Research and Development Program of China (No.2021YFD2200405)the National Natural Science Foundation of China (No.31930078)。
文摘Root-associated microbes play an essentialrole in mediating plant growth,health,and habitat adaptability.However,it is unknown which microbial taxa help develop host fitness and how habitats shape root-associated microbial assembly patterns.As an endemic species of subalpine forests in western Sichuan,China,Minjiang fir(Abies fargesii var.faxoniana)is dominant on cold-shaded northwestern slopes while absent on warm sunlit southwestern slopes.In this study,fungal and bacterial communities were investigated in three spatial compartments(endosphere,rhizosphere,and bulk soil)associated with Minjiang fir saplings on a cold-shaded northwestern slope and a warm sunlit southwestern slope.Habitats differentiated the microbial communities regardless of the spatial compartment and microbial taxa.Slope aspect variations caused shifts in root-associated(rhizosphere and endosphere)microbial compositions.Compared with the southwestern slope,the cold-shaded northwestern slope harbored a higher abundance of the growth-promoting bacteria Burkholderia and ectomycorrhizal fungi Cortinarius and Piloderma.The slope aspect had stronger effects on fungal diversity than bacterial diversity,with higher fungal endemism and lower bacterial endemism.Slope aspect variations were the dominant drivers of root-associated microbial communities,with lower contribution by soil properties and higher contribution by plant traits on the northwestern slope.Findings from this study could improve the understanding of plant habitat adaptability from the perspective of microbial community assembly.It is suggested that forest management should consider root-associated microbiomes for enhancing species fitness and habitat adaptability.
文摘Ticks transmit a diverse array of microbes to vertebrate hosts,including human pathogens,which has led to a human-centric focus in this vector system.Far less is known about pathogens of ticks themselves.Here,we discover that a toxin in blacklegged ticks(Ixodes scapularis)horizontally acquired from bacteria-called domesticated amidase effector 2(dae2)-has evolved to kill mammalian skin microbes with remarkable efficiency.Secreted into the saliva and gut of ticks,Dae2 limits skin-associated staphylococci in ticks while feeding.In contrast,Dae2 has no intrinsic ability to kill Borrelia burgdorferi,the tick-borne Lyme disease bacterial pathogen.These findings suggest ticks resist their own pathogens while tolerating symbionts.Thus,just as tick symbionts can be pathogenic to humans,mammalian commensals can be harmful to ticks.Our study underscores how virulence is context-dependent and bolsters the idea that"pathogen"is a status and not an identity.
基金Supported by the National Natural Science Foundation of China (No.60372012) and NSF of Chongqing (No.0831)
文摘Stability, boundedness and persistence are three important aspects for an ecological model. In this paper, a further analysis of a class of anaerobic digestion ecological models is performed. Based on the Liupunov Method, the local stability of all equilibria in the system is got. According to the vector fields described by the system, the proof of the boundedness of the solution on the anaerobic digestion processes is completed in three steps. The method proposed in the discussion on the boundedness can be generalized to the similar problems. Results in this paper give information on how to run the ecological system well by adjusting the system parameters.
基金supported by the National Natural Science Foundation of China funded project(32172627)Chongqing Modern Tea Technology System for Efficient Agriculture in Mountainous Areas 2022[8]the Germplasm Creation Research Program of Southwest University。
文摘Pu-erh tea has been shown to reduce gut inflammation in dextran sulfate sodium(DSS)-induced mice.Also,we found abnormal liver cholesterol metabolism in DSS-induced mice.However,it's not clear how Pu-erh tea improves DSS-induced impaired liver cholesterol metabolism.Here,we established the DSS-induced model and clarified that DSS exacerbated gut inflammation accompanied by disorders of liver cholesterol metabolism.Pu-erh tea reshaped gut microbes,limited gut oxidative stress and inflammation(nicotinamide adenine dinucleotide phosphate oxidase 2/reactive oxygen species/myeloid differentiation primary response protein 88/nuclear factor kappa-B,24.97%-52.89%),reduced gut bile acid reabsorption(up-regulation of farnesoid X receptor(FXR)/fibroblast growth factor 15,24.53%-55.91%),and promoted liver bile acid synthesis(up-regulation of peroxisome proliferator-activated receptor-α/cholesterol 7-alpha hydroxylase,34.65%-79.14%),thereby partly restoring liver cholesterol metabolism(regulated FXR/small heterodimer partner/sterol-regulatory element binding proteins,53.19%-95.40%).Altered bile acid metabolic profiles(increased chenodeoxycholic acid,ursodeoxycholic acid,lithocholic acid,etc.)may also improve liver cholesterol metabolism by altering gut and liver inflammation.Thus,gut microbial reshaping and altered bile acid metabolism may be key targets of Pu-erh tea for improving DSS-induced liver cholesterol metabolism disorders via the gut-gut microbe-bile acid-liver axis.
