【Objectives】Si and microbial application could relieve the crop replanting problems(CRPs).We further studied the change of key microorganisms that are related to the beneficial effects,aiming at provide reference fo...【Objectives】Si and microbial application could relieve the crop replanting problems(CRPs).We further studied the change of key microorganisms that are related to the beneficial effects,aiming at provide reference for the manufacture and application of both microbial agents and Si fertilizer in food lily production.【Methods】A field experiment was conducted over a three-year period,from March 2019 to March 2022.The experimental field had been continuously cultivated with lily for 9 years.Three treatments were established:silicon fertilizer(SF),microbial agents(“Special 8^(TM)”,MF),and combined application of silicon fertilizer and microbial agents(SMF).A control group with blank soil(CK)was also included.At seedling stage of Lanzhou lilies in 2020 and 2021,the shoot and bulb dry weight,and the plant height and stem diameter of Lanzhou lilies were investigated for calculation of seedling index.In July 2020,20 plants were selected in each plot,and root zone soils were sampled at a depth of 20 cm,10 cm away from the roots,and then mixed to form a composite sample.The soil available Si and organic matter content were analyzed,and the fungal community structure and some specific microbial groups in soils were determined with high-throughput sequencing of ITS.【Results】All the three treatments significantly enhanced the lily plant growth and the seedling index,compared to CK.Besides,SF and MF treatments increased the relative abundances(RA)and diversity of fungal communities,and altered the community structures.The RA of some specific groups were found to be significantly correlated with the seedling index and/or soil available Si.Of them,the RA of the genera Fusarium,Dactylonectria,Humicola,Stilbella,and the species Humicola_grisea showed a positive correlation,while that of the genera Mortierella,Stilbella,Holtermanniella,and the species Mortierella_fatshederae showed a negative correlation with seedling index.The genera Fusarium,Stilbella,the species Humicola_grisea,and Dactylonectria_estremocensis showed a positive correlation,while the genura Stilbella,and the species Mortierella fatshederae showed a negative correlation with available Si content.In the co-occurence network of top twenty fungal genera and top sixteen bacterial genera(RA>0.2%),Holtermanniella was the only genus that interacted with the bacteria and negatively correlated with bacterial genus Blastococcus.Holtermanniella was also the most densely connected genera,followed by the genus Fusarium,Didymella and Humicola.In addition,the genus Holtermanniella was the key species connecting fungal and bacterial community in soil.Fungal functional prediction revealed that SF,MF and SMF treatments decreased plant pathogens guilds and increased the beneficial guilds Ectomycorrhizal,plant saprophyte,leaf saprophyte,and arbuscular mycorrhizal compared to CK.【Conclusions】Combined application of silicon fertilizer and microbial agents can alleviate continuous replanting problems of Lanzhou lilies through restoring the fungal community diversity,and promoting plant residue depredation,thus reducing soil born disease incidence.The beneficial genus Humicola and its one species H.grisea acts as bioconversion,and the genus Acremonium acts as plant pathogen inhibitor.展开更多
Paddy fields are considered a major source of methane(CH_4)emissions.Aerobic irrigation methods have proven to be efficacious in mitigating CH_4 emissions in paddy cultivation.The promising role of compound microbial ...Paddy fields are considered a major source of methane(CH_4)emissions.Aerobic irrigation methods have proven to be efficacious in mitigating CH_4 emissions in paddy cultivation.The promising role of compound microbial agents in refining the rhizospheric ecosystem suggests their potential as novel agents in reducing CH_4 emissions from paddy fields.To explore a new method of using compound microbial agents to reduce CH_4 emissions,we conducted pot and field experiments over the period of 2022-2023.We measured CH_4 flux,the redox potential(Eh)of the soil,the concentration of dissolved oxygen(DO)in the floodwater,and the gene abundance of both methanogens(mcr A)and methanotrophs(pmo A).The results showed that the application of the compound microbial agent led to a significant increase in the DO levels within the floodwater and an increase of 9.26%to 35.01%in the Eh of the tillage soil.Furthermore,the abundance of pmo A increased by 31.20%,while the mcr A/pmo A ratio decreased by 25.96%at the maximum tillering stage.Applying 45-75 kg/hm^(2) of the compound microbial agent before transplanting resulted in a reduction of cumulative CH_4 emissions from paddy fields by 17.49%in single-cropped rice and 43.54%to 50.27%in double-cropped late rice during the tillering stage.Correlation analysis indicated that CH_4 flux was significantly negatively correlated with pmo A gene abundance and soil Eh,and positively related to the mcr A/pmo A ratio.Additionally,soil Eh was significantly positively correlated with pmo A gene abundance,suggesting that paddy soil Eh indirectly affected CH_4 flux by influencing the pmo A gene abundance.In conclusion,the pre-planting application of the compound microbial agent at a rate of 45-75 kg/hm^(2) can enhance the Eh in the rhizosphere and increase the abundance of the pmo A gene,thereby reducing CH_4 emissions from paddy fields during the tillering stage of rice growth.展开更多
Microbial enhanced oil recovery(MEOR)is a cost effective and efficient method for recovering residual oil.However,the presence of wax(paraffin)in residual oil can substantially reduce the efficiency of MEOR.Therefore,...Microbial enhanced oil recovery(MEOR)is a cost effective and efficient method for recovering residual oil.However,the presence of wax(paraffin)in residual oil can substantially reduce the efficiency of MEOR.Therefore,microbial dewaxing is a critical process in MEOR.In this study,a bacterial dewaxing agent of three spore-forming bacteria was developed.Among these bacteria,Bacillus subtilis GZ6 produced the biosurfactant surfactin.Replacing the promoter of the surfactin synthase gene cluster(srfA),increased the titer of surfactin in this strain from 0.33 g/L to 2.32 g/L.The genetically modified strain produced oil spreading rings with diameters increasing from 3.5±0.1 to 4.1±0.2 cm.The LadA F10L/N133R mutant was created by engineering an alkane monooxygenase(LadA)using site-directed mutagenesis in the Escherichia coli host.Compared to the wild-type enzyme,the resulting mutant exhibited an 11.7-fold increase in catalytic efficiency toward the substrate octadecane.When the mutant(pIMPpladA2mu)was expressed in Geobacillus stearothermophilus GZ178 cells,it exhibited a 2.0-fold increase in octadecane-degrading activity.Cultures of the two modified strains(B.subtilis GZ6(pg3srfA)and G.stearothermophilus GZ178(pIMPpladA2mu))were mixed with the culture of Geobacillus thermodenitrificans GZ156 at a ratio of 5:80:15.The resulting composition increased the rate of wax removal by 35%compared to the composition composed of three native strains.This study successfully developed a multi-strain bacterial agent with enhanced oil wax removal capabilities by genetically engineering two bacterial strains.展开更多
Microbial activity and interaction are the important driving factors in the start-up phase of food waste composting at low temperature.The aim of this study was to explore the effect of inoculating Bacillus lichenifor...Microbial activity and interaction are the important driving factors in the start-up phase of food waste composting at low temperature.The aim of this study was to explore the effect of inoculating Bacillus licheniformis on the degradation of organic components and the potential microbe-driven mechanism from the aspects of organic matter degradation,enzyme activity,microbial community interaction,and microbial metabolic function.The results showed that after inoculating B.licheniformis,temperature increased to 47.8℃ on day2,and the degradation of readily degraded carbohydrates(RDC)increased by 31.2%,and the bioheat production increased by 16.5%.There was an obvious enhancement of extracellular enzymes activities after inoculation,especially amylase activity,which increased by 7.68 times on day 4.The inoculated B.licheniformis colonized in composting as key genus in the start-up phase.Modular network analysis and Mantel test indicated that inoculation drove the cooperation between microbial network modules who were responsible for various organic components(RDC,lipid,protein,and lignocellulose)degradation in the start-up phase.Metabolic function prediction suggested that carbohydrate metabolisms including starch and sucrose metabolism,glycolysis/gluconeogenesis,pyruvate metabolism,etc.,were improved by increasing the abundance of related functional genes after inoculation.In conclusion,inoculating B.licheniformis accelerated organic degradation by driving the cooperation between microbial network modules and enhancing microbial metabolism in the start-up phase of composting.展开更多
By using red soil and late rice Wufengyou T025 as the tested materials,the influences of straw returning with a microbial agent on the quantity of microorganisms and enzyme activity in rhizosphere soil in fields were ...By using red soil and late rice Wufengyou T025 as the tested materials,the influences of straw returning with a microbial agent on the quantity of microorganisms and enzyme activity in rhizosphere soil in fields were studied,and soil productivity was tested with yield and agricultural traits of late rice. The results showed that straw returning with the microbial agent could significantly improve the quantity of bacteria,fungi and actinomyces in soil,enhance the activity of sucrase,urease,catalase and cellulase,and improve the number of grains per spike,setting percentage,thousand seed weight and yield of late rice. The combination of rice straw returning and the microbial agent has a good prospect of application.展开更多
[ Objectives] The paper was to study effects of different microbial agents on occurrence of tobacco bacterial wilt. [ Methods I Antagonistic strains against Ralstonia solanacearum were screened from in situ soil, and ...[ Objectives] The paper was to study effects of different microbial agents on occurrence of tobacco bacterial wilt. [ Methods I Antagonistic strains against Ralstonia solanacearum were screened from in situ soil, and prepared into four different combinations. The number of soil microorganisms and incidence of bacterial wilt of four combinations were observed. [ Results] The incidence rate of bacterial wilt treated by microbial agent OR-1 was significantly lower than that in control, and the control efficacy against bacterial wilt reached 67%. [ Conclusions] Application of microbial agent OR-1 could effectively reduce the incidence rate and disease index of bacterial wilt, thus improving the quality of tobacco.展开更多
The microbial agent ARC-BBBE demonstration trials were conducted in four provinces in the main peanutproducing areas of the Huang-huai-hai plain of China.The results revealed that the application of ARC-BBBE led to a ...The microbial agent ARC-BBBE demonstration trials were conducted in four provinces in the main peanutproducing areas of the Huang-huai-hai plain of China.The results revealed that the application of ARC-BBBE led to a 1.09–1.70 fold increase in the number of nodules in the treatment group at the demonstration site compared to the control group.Moreover,the nodule weight in the treatment group was 0.80–3.32 times higher than that of the control group,and nitrogenase activity per plant showed a significant enhancement by 1.00–2.83 fold compared to controls.Additionally,notable improvements were observed in terms of increased fresh weight of whole plants,well-filled pod numbers,and enhanced growth performance;ultimately resulting in a harvest yield increase ranging from 9.46%to 49.04%.The abundance of Aspergillus flavus in rhizosphere soil was determined by the dilution spread plate method,and the inhibition rate was up to 86.7%.The application of ARC-BBBE in the significant peanut-producing areas of Huang-huai-hai has effects of promoting growth,nodulation,and increasing production.At the same time,it has the effect of inhibiting and controlling soil Aspergillus flavus,which provides a new green and low-carbon way to promote the high-quality development of the peanut industry.展开更多
Microbial inoculation agent has been widely used in waste disposal and waste recycling. In this paper, the principle of fermentation in the composting of agricultural waste and the impact of microbial inoculation agen...Microbial inoculation agent has been widely used in waste disposal and waste recycling. In this paper, the principle of fermentation in the composting of agricultural waste and the impact of microbial inoculation agent on composting were reviewed.The research and the application of microbial inoculation agent were also introduced. Based on the trend of the research, the promising prospect of microbial inoculation agent was discussed.展开更多
To explore the influence of microbial agems on the decomposition of aging dunnage of the fermentation bed, this paper took the aging dunnage as the raw materials, obtained microbial strains of different types through ...To explore the influence of microbial agems on the decomposition of aging dunnage of the fermentation bed, this paper took the aging dunnage as the raw materials, obtained microbial strains of different types through isolation and purification, chose dominant groups to make compound microbial agents, and adopted composting decomposition experiment. The results showed that Bacillus subtilis of different ratios was added, Trichoderma koningii and Thermo actinomycetaceac could promote the decomposition of aging dunnage, especially composite microbial agents （Kc：Kn：Gf = 1：1：1 ） had the best effect of decomposition, the high tem- perature was kept for 13 days. In the end of composting, degradation rate of cellulose, degradation rate of lignin, GI, and C/N were 47.6%, 30. 2%, 98.5%, and 18.5%. Bacillus coli was not detected.展开更多
[ Objective] The aim of this study was to develop a cheap and localized microbial agent so as to solve high cost of microbial agent for pig manure composting in Jiaxing City. [ Method] Pig manure in the experimental g...[ Objective] The aim of this study was to develop a cheap and localized microbial agent so as to solve high cost of microbial agent for pig manure composting in Jiaxing City. [ Method] Pig manure in the experimental group and control group was inoculated with the self-developed micro- bial agent and commercial microbial agent, respectively. The manure was decomposed for 38 d, during which the indicators of compost including physical properties, temperature, pH value, water content, organic matter, dissolved nitrogen, carbon nitrogen ratio and germination rate were studied. [ Result] The water content in the experimental group declined to 26.10% after 33 d of compost, meeting the standard upper limitation of 30% for maturity. By comparison, the water content in the control group was slightly higher than 30% even after 38 d. The germination rate of seeds fertilized with the experimental manure compost met the standard for maturity on Day 28, while that in the control group met the standard for maturity on Day 35. When the composting was finished, the ratio of total carbon to total nitrogen in the pig manure was 14.64 and 16.43 respective- ly in the experimental and control group, and the organic matter content was about 45% for both. All these indexes could meet the standards for or- ganic fertilizer products. [ Conclusion] The self-developed microbial agent can moot the requirements for pig manure composting, and it can shorten the composting time by 5 -8 d compared with the commercial agent. In addition, the fertilizer product composted by the self-developed microbial a qent has lower water content and thereby is much more beneficial for preservation.展开更多
For the control of environment pollution caused by livestock and poultry manure, four microbial strains conducive to aerobic composting were selected and mixed into four compound microbial agents, and effects of diffe...For the control of environment pollution caused by livestock and poultry manure, four microbial strains conducive to aerobic composting were selected and mixed into four compound microbial agents, and effects of different compound microbial agents on aerobic composting of cow manure were studied from aspects of changes in temperature, pH, water content and C/N during the composting process. The results show that microbial agent M2 has the best effect for aerobic composting of cow manure, so microbial agent M2 has broad popularization and application prospect in livestock and poultry farms in low-temperature areas of Northeast China.展开更多
Single or mixed use ofAgaricus bisporus residue and microbial agent had better control effect on cucumber root-knot nematode disease in greenhouse. The results showed that the control effect of single use of A. b/spor...Single or mixed use ofAgaricus bisporus residue and microbial agent had better control effect on cucumber root-knot nematode disease in greenhouse. The results showed that the control effect of single use of A. b/sporus residue was 32.9% - 34.7%, and the yield increasing rate was 2.1% - 8.7% ; the control effect of mixed use ofA. b/sporus residue and microbial agent was 59. 1% - 63. 6%, and yield increasing rate was 2.6% - 3.5%. The experimental dose had no ad- verse effects on soil physical and chemical properties. The mixed use of A. b/sporus residue and microbial agent was one of the effective ways to control root-knot nematode disease.展开更多
In order to clarify the influence of microbial agents on kitchen waste and rice straw composting, an aerobic composting experiment was conducted by setting three kinds of combined bacterial agents to study the tempera...In order to clarify the influence of microbial agents on kitchen waste and rice straw composting, an aerobic composting experiment was conducted by setting three kinds of combined bacterial agents to study the temperature change in the composting, and pH value, nutrient contents, C/N and heavy metal content after composting through. The three kinds of combined bacterial agents were as follows:B1 with effective strains: Bacillus subtilis, yeast and Trichoderma sp.;B2 with effective strains: Bacillus amyloliquefaciens, yeast and lactic acid bacteria;B3 with effective strains: Bacillus subtilis, yeast and lactic acid bacteria. Results showed that the addition of microbial agents had signifcant effects on temperature change,nitrogen and phosphorus content and C/N of the compost. T1, T2, and T3 treatments lasted for 8, 5 and 4 d in the thermophilic phase above 60℃, respectively. The total nitrogen content of each treatment was 14.90, 15.50 and 13.80 g/kg respectively after composting. The total phosphorus content of each treatment was 4.87, 4.17 and 3.70g/kg respectively at the end of composting. The C/N of each treatment was 20.94,22.63, and 22.65 respectively at the end of composting. The application effect of B1bacteria agent on the composting of kitchen waste and rice straw was better.展开更多
Several quinolino-benzoxaborole derivatives have been prepared to start from aminobenzoxaboroles. These derivatives have been evaluated for their anti-cancer activity on human and murine cancer cell lines and based on...Several quinolino-benzoxaborole derivatives have been prepared to start from aminobenzoxaboroles. These derivatives have been evaluated for their anti-cancer activity on human and murine cancer cell lines and based on their relative non-toxicity, these compounds were further evaluated for their antibacterial activity against E. coli, B. subtilis, and M. smegmatis. The synthesized compounds were also evaluated for antifungal activity in C. albicans and C. neoformans.展开更多
The present study sought to assess the rational use of antimicrobial agents in a Brazilian intensive care unit (ICU) and its association with antimicrobial resistance in elderly patients admitted to the unit. Results:...The present study sought to assess the rational use of antimicrobial agents in a Brazilian intensive care unit (ICU) and its association with antimicrobial resistance in elderly patients admitted to the unit. Results: Choice of empiric and sensitivity-guided therapy was inadequate in > 80% and 59% of cases respectively. Inadequate antimicrobial therapy, whether empiric or sensitivity-guided, was positively correlated with bacterial resistance (r = 0.316;p = 0.001). Sensitivity testing revealed a 46.5% resistance rate to eight out of the ten most commonly used antibiotics. Multiple drug-resistant organisms were found in 40.8% of patients. A significant increase was observed in the number of multidrug-resistant samples between 2006/2007 and 2008 (r = 0.41, p = 0.006), (r = 0.598, p = 0.001), (r = 0.688, p = 0.00). Conclusion: We found a high rate of antibiotic misuse in the study sample. Inadequate therapy was correlated with resistance to antimicrobial agents.展开更多
Agricultural areas of land are deteriorating every day owing to population increase, rapid urbanization, and industrialization. To feed today’s huge populations, increased crop production is required from smaller are...Agricultural areas of land are deteriorating every day owing to population increase, rapid urbanization, and industrialization. To feed today’s huge populations, increased crop production is required from smaller areas, which warrants the continuous application of high doses of inorganic fertilizers to agricultural land. These cause damage to soil health and, therefore, nutrient imbalance conditions in arable soils. Under these conditions, the benefits of microbial inoculants (such as Actinobacteria) as replacements for harmful chemicals and promoting ecofriendly sustainable farming practices have been made clear through recent technological advances. There are multifunctional traits involved in the production of different types of bioactive compounds responsible for plant growth promotion, and the biocontrol of phytopathogens has reduced the use of chemical fertilizers and pesticides. There are some well-known groups of nitrogen-fixing Actinobacteria, such as Frankia, which undergo mutualism with plants and offer enhanced symbiotic trade-offs.In addition to nitrogen fixation, increasing availability of major plant nutrients in soil due to the solubilization of immobilized forms of phosphorus and potassium compounds, production of phytohormones, such as indole-3-acetic acid, indole-3-pyruvic acid, gibberellins, and cytokinins, improving organic matter decomposition by releasing cellulases, xylanase, glucanases, lipases, and proteases, and suppression of soil-borne pathogens by the production of siderophores, ammonia, hydrogen cyanide, and chitinase are important features of Actinobacteria useful for combating biotic and abiotic stresses in plants.The positive influence of Actinobacteria on soil fertility and plant health has motivated us to compile this review of important findings associated with sustaining plant productivity in the long run.展开更多
Marine sediment samples were collected from the coastal areas of Southern India, particularly in Kanyakumari District. Twenty-eight different fungal strains were isolated. The screening of fungi from marine sediment w...Marine sediment samples were collected from the coastal areas of Southern India, particularly in Kanyakumari District. Twenty-eight different fungal strains were isolated. The screening of fungi from marine sediment was done to isolate a potent fungus that can produce bioactive compounds for biomedical applications. Only three strains viz Trichoderma gamsii SP4, Talaromyces flavus SP5 and Aspergillus oryzae SP6 were screened for further studies. The intracellular bioactive compounds were extracted using solvent extraction method. The crude extracts were tested for its anti-microbial and anti-cancer properties and analytically characterized using Gas Chromatography Mass Spectrometry(GC-MS). All the three extracts were active, but the extract from T. flavus SP5 was found to be more active against various human pathogens, viz., Pseudomonas aeruginosa ATCC 27853(17.8 ± 0.1), Escherichia coli ATCC 52922(18.3 ± 0.3), and Candida tropicalis ATCC 750(17.7 ± 0.4). It also exhibited cytotoxic activity against HEp2 carcinoma cell line with the LC_(50) value of 25.7 μg·mL^(-1). The GC-MS data revealed the presence of effective bioactive compounds. These results revealed that the extract from isolated fungus T. flavus SP5 acted as a potent antimicrobial, antifungal, and anticancer agent, providing basic information on the potency of marine fungi towards biomedical applications; further investigation may lead to the development of novel anticancer drugs.展开更多
The relative toxicity of 48 anilines using the Tetrahymena pyriformis population growth characteristics IGC50 （concentration causing 50% growth inhibition）, available in the literature, was studied. At first, the en...The relative toxicity of 48 anilines using the Tetrahymena pyriformis population growth characteristics IGC50 （concentration causing 50% growth inhibition）, available in the literature, was studied. At first, the entire data set was randomly split into a training set （31 chemicals） used to establish the QSAR model, and a test set （17 chemicals） for statistical external validation. A biparametric model was developed using, as independent variables, 3D theoretical descriptors derived from DRAGON software. The GA-MLR （genetic algorithm variable subset selection） procedure was performed on the trainingset by the software mobydigs using the OLS （ordinary least squares） regression method, and GA（genetic algorithm）-VSS（variable subset selection） by maximising the cross-validated explained variance （Q^2Loo）＇ The obtained model was examined for robustness （Q^2LOOcross-validation, Y-scrambling） and predictive ability through both internal （Q^2LM0, bootstrap） and external validation （Q^2ext） methods. Descriptors included in the QSAR model indicated that log/GC^-150 value was related to molecular size and shape, and interaction of molecule with its surrounding medium or its target. Moreover, the applicability domain of the model was discussed.展开更多
Response surface methodology and central composite rotatable design （CCRD） for K = 3 were used to investigate the combined effect of blanching time （0-1 min）, processing time （10-30 min） and sodium metabisulphi...Response surface methodology and central composite rotatable design （CCRD） for K = 3 were used to investigate the combined effect of blanching time （0-1 min）, processing time （10-30 min） and sodium metabisulphite （Na2S205） salt concentration （0%-2%） on vitamin C content, hardness （texture）, microbial count and color intensity of green pepper （Capsicum sinensis） during canning. Blanching, processing time and sodium metabisulphite （Na2S205） salt concentration all had variable effects on the vitamin C, microbial quality and sensory characteristics of the canned green peppers. Significant （P 〈 0.05） interactions were noted between all the factors with high regression coefficients （78.7%-97.0%）. Increasing processing time caused significant decreases in vitamin C and microbial load of the product. However, salt concentration had only marginal and insignificant effect on the vitamin C content of the canned product. Sensory evaluation on the product showed that both the pre-processing conditions and of blanching and salt concentrations, and the processing time had varied effects on the color and hardness of the products. Hardness of the canned products generally decreased with increasing processing time and blanching time, while only minimal and insignificant effects were noted with blanching time. Increasing blanching time caused significant increasing retention of the dark green color of the peppers with only slight but insignificant increases noted with processing time, while increases in salt concentration consistently reduced the dark green color of the products. The optimum pre-processing and processing conditions that yielded products with high preference and consumer-acceptability were： blanching time of 0 min, processing time of 10 min and sodium metabisulphite concentration of 0.2%.展开更多
基金Key Research project of Gansu Province of China(22YF7NA108)National Natural Science Foundation of China(31860549)+1 种基金Industry Supporting Project from Education Department of Gansu Province(2023CYZC-49)Major Science and Technology project of Gansu province(24ZDNA006)。
文摘【Objectives】Si and microbial application could relieve the crop replanting problems(CRPs).We further studied the change of key microorganisms that are related to the beneficial effects,aiming at provide reference for the manufacture and application of both microbial agents and Si fertilizer in food lily production.【Methods】A field experiment was conducted over a three-year period,from March 2019 to March 2022.The experimental field had been continuously cultivated with lily for 9 years.Three treatments were established:silicon fertilizer(SF),microbial agents(“Special 8^(TM)”,MF),and combined application of silicon fertilizer and microbial agents(SMF).A control group with blank soil(CK)was also included.At seedling stage of Lanzhou lilies in 2020 and 2021,the shoot and bulb dry weight,and the plant height and stem diameter of Lanzhou lilies were investigated for calculation of seedling index.In July 2020,20 plants were selected in each plot,and root zone soils were sampled at a depth of 20 cm,10 cm away from the roots,and then mixed to form a composite sample.The soil available Si and organic matter content were analyzed,and the fungal community structure and some specific microbial groups in soils were determined with high-throughput sequencing of ITS.【Results】All the three treatments significantly enhanced the lily plant growth and the seedling index,compared to CK.Besides,SF and MF treatments increased the relative abundances(RA)and diversity of fungal communities,and altered the community structures.The RA of some specific groups were found to be significantly correlated with the seedling index and/or soil available Si.Of them,the RA of the genera Fusarium,Dactylonectria,Humicola,Stilbella,and the species Humicola_grisea showed a positive correlation,while that of the genera Mortierella,Stilbella,Holtermanniella,and the species Mortierella_fatshederae showed a negative correlation with seedling index.The genera Fusarium,Stilbella,the species Humicola_grisea,and Dactylonectria_estremocensis showed a positive correlation,while the genura Stilbella,and the species Mortierella fatshederae showed a negative correlation with available Si content.In the co-occurence network of top twenty fungal genera and top sixteen bacterial genera(RA>0.2%),Holtermanniella was the only genus that interacted with the bacteria and negatively correlated with bacterial genus Blastococcus.Holtermanniella was also the most densely connected genera,followed by the genus Fusarium,Didymella and Humicola.In addition,the genus Holtermanniella was the key species connecting fungal and bacterial community in soil.Fungal functional prediction revealed that SF,MF and SMF treatments decreased plant pathogens guilds and increased the beneficial guilds Ectomycorrhizal,plant saprophyte,leaf saprophyte,and arbuscular mycorrhizal compared to CK.【Conclusions】Combined application of silicon fertilizer and microbial agents can alleviate continuous replanting problems of Lanzhou lilies through restoring the fungal community diversity,and promoting plant residue depredation,thus reducing soil born disease incidence.The beneficial genus Humicola and its one species H.grisea acts as bioconversion,and the genus Acremonium acts as plant pathogen inhibitor.
基金supported by the Zhejiang‘Ten Thousand Talents’Plan Science and Technology Innovation Leading Talent Project,China (Grant No.2020R52035)the National Rice Industry Technology System of China (Grant No.CARS-01-31)the Agricultural Science and Technology Innovation Program,China (Grant No.CAAS-ZDRW202001)。
文摘Paddy fields are considered a major source of methane(CH_4)emissions.Aerobic irrigation methods have proven to be efficacious in mitigating CH_4 emissions in paddy cultivation.The promising role of compound microbial agents in refining the rhizospheric ecosystem suggests their potential as novel agents in reducing CH_4 emissions from paddy fields.To explore a new method of using compound microbial agents to reduce CH_4 emissions,we conducted pot and field experiments over the period of 2022-2023.We measured CH_4 flux,the redox potential(Eh)of the soil,the concentration of dissolved oxygen(DO)in the floodwater,and the gene abundance of both methanogens(mcr A)and methanotrophs(pmo A).The results showed that the application of the compound microbial agent led to a significant increase in the DO levels within the floodwater and an increase of 9.26%to 35.01%in the Eh of the tillage soil.Furthermore,the abundance of pmo A increased by 31.20%,while the mcr A/pmo A ratio decreased by 25.96%at the maximum tillering stage.Applying 45-75 kg/hm^(2) of the compound microbial agent before transplanting resulted in a reduction of cumulative CH_4 emissions from paddy fields by 17.49%in single-cropped rice and 43.54%to 50.27%in double-cropped late rice during the tillering stage.Correlation analysis indicated that CH_4 flux was significantly negatively correlated with pmo A gene abundance and soil Eh,and positively related to the mcr A/pmo A ratio.Additionally,soil Eh was significantly positively correlated with pmo A gene abundance,suggesting that paddy soil Eh indirectly affected CH_4 flux by influencing the pmo A gene abundance.In conclusion,the pre-planting application of the compound microbial agent at a rate of 45-75 kg/hm^(2) can enhance the Eh in the rhizosphere and increase the abundance of the pmo A gene,thereby reducing CH_4 emissions from paddy fields during the tillering stage of rice growth.
基金the financial support from Scientific Research Program of Beijing Municipal Commission of Education(KM202110017009,granted to Xiaoyan Guo)Undergraduates Research Training Program of Beijing Institute of Petrochemical Technology(2022J00178,granted to Lizhu Li)。
文摘Microbial enhanced oil recovery(MEOR)is a cost effective and efficient method for recovering residual oil.However,the presence of wax(paraffin)in residual oil can substantially reduce the efficiency of MEOR.Therefore,microbial dewaxing is a critical process in MEOR.In this study,a bacterial dewaxing agent of three spore-forming bacteria was developed.Among these bacteria,Bacillus subtilis GZ6 produced the biosurfactant surfactin.Replacing the promoter of the surfactin synthase gene cluster(srfA),increased the titer of surfactin in this strain from 0.33 g/L to 2.32 g/L.The genetically modified strain produced oil spreading rings with diameters increasing from 3.5±0.1 to 4.1±0.2 cm.The LadA F10L/N133R mutant was created by engineering an alkane monooxygenase(LadA)using site-directed mutagenesis in the Escherichia coli host.Compared to the wild-type enzyme,the resulting mutant exhibited an 11.7-fold increase in catalytic efficiency toward the substrate octadecane.When the mutant(pIMPpladA2mu)was expressed in Geobacillus stearothermophilus GZ178 cells,it exhibited a 2.0-fold increase in octadecane-degrading activity.Cultures of the two modified strains(B.subtilis GZ6(pg3srfA)and G.stearothermophilus GZ178(pIMPpladA2mu))were mixed with the culture of Geobacillus thermodenitrificans GZ156 at a ratio of 5:80:15.The resulting composition increased the rate of wax removal by 35%compared to the composition composed of three native strains.This study successfully developed a multi-strain bacterial agent with enhanced oil wax removal capabilities by genetically engineering two bacterial strains.
基金supported by the Open Research Fund Program of State Environmental Protection Key Laboratory of Food Chain Pollution Control(No.FC2022YB01)the National Natural Science Foundation of China(No.32071552)+1 种基金the Independent Research Project of Science and Technology Innovation Base in Tibet Autonomous Region(No.XZ2022JR0007G)China Agricultural University-Dabeinong Group Professional degree graduate joint training reform project(No.CAUDBN PDG-JTRP).
文摘Microbial activity and interaction are the important driving factors in the start-up phase of food waste composting at low temperature.The aim of this study was to explore the effect of inoculating Bacillus licheniformis on the degradation of organic components and the potential microbe-driven mechanism from the aspects of organic matter degradation,enzyme activity,microbial community interaction,and microbial metabolic function.The results showed that after inoculating B.licheniformis,temperature increased to 47.8℃ on day2,and the degradation of readily degraded carbohydrates(RDC)increased by 31.2%,and the bioheat production increased by 16.5%.There was an obvious enhancement of extracellular enzymes activities after inoculation,especially amylase activity,which increased by 7.68 times on day 4.The inoculated B.licheniformis colonized in composting as key genus in the start-up phase.Modular network analysis and Mantel test indicated that inoculation drove the cooperation between microbial network modules who were responsible for various organic components(RDC,lipid,protein,and lignocellulose)degradation in the start-up phase.Metabolic function prediction suggested that carbohydrate metabolisms including starch and sucrose metabolism,glycolysis/gluconeogenesis,pyruvate metabolism,etc.,were improved by increasing the abundance of related functional genes after inoculation.In conclusion,inoculating B.licheniformis accelerated organic degradation by driving the cooperation between microbial network modules and enhancing microbial metabolism in the start-up phase of composting.
基金Supported by National Key Research and Development Program of China(2017YFD0200808)National Key Technology R&D Program in the 11th Five-Year Plan of China(2006BAD02A04)+1 种基金Innovation Foundation for Postgraduates in Jiangxi Province(YC10A056)Free Declaration Project of Jiangxi Agricultural University
文摘By using red soil and late rice Wufengyou T025 as the tested materials,the influences of straw returning with a microbial agent on the quantity of microorganisms and enzyme activity in rhizosphere soil in fields were studied,and soil productivity was tested with yield and agricultural traits of late rice. The results showed that straw returning with the microbial agent could significantly improve the quantity of bacteria,fungi and actinomyces in soil,enhance the activity of sucrase,urease,catalase and cellulase,and improve the number of grains per spike,setting percentage,thousand seed weight and yield of late rice. The combination of rice straw returning and the microbial agent has a good prospect of application.
基金Supported by Science and Technology Project of Nanping Branch of Fujian Tobacco Company(NYK2012-14-3)
文摘[ Objectives] The paper was to study effects of different microbial agents on occurrence of tobacco bacterial wilt. [ Methods I Antagonistic strains against Ralstonia solanacearum were screened from in situ soil, and prepared into four different combinations. The number of soil microorganisms and incidence of bacterial wilt of four combinations were observed. [ Results] The incidence rate of bacterial wilt treated by microbial agent OR-1 was significantly lower than that in control, and the control efficacy against bacterial wilt reached 67%. [ Conclusions] Application of microbial agent OR-1 could effectively reduce the incidence rate and disease index of bacterial wilt, thus improving the quality of tobacco.
基金The authors thank the National Natural Sciences Foundation of China(32030085,U22A20551)Major project of Hubei Hongshan Laboratory(2021hszd015)+1 种基金Agricultural Science and Technology Innovation Program of Chinese Academy of Agricultural Sciences(CAAS-ASTIP2021-OCRI)Knowledge Innovation Program of Wuhan-Shuguang Project(3570).
文摘The microbial agent ARC-BBBE demonstration trials were conducted in four provinces in the main peanutproducing areas of the Huang-huai-hai plain of China.The results revealed that the application of ARC-BBBE led to a 1.09–1.70 fold increase in the number of nodules in the treatment group at the demonstration site compared to the control group.Moreover,the nodule weight in the treatment group was 0.80–3.32 times higher than that of the control group,and nitrogenase activity per plant showed a significant enhancement by 1.00–2.83 fold compared to controls.Additionally,notable improvements were observed in terms of increased fresh weight of whole plants,well-filled pod numbers,and enhanced growth performance;ultimately resulting in a harvest yield increase ranging from 9.46%to 49.04%.The abundance of Aspergillus flavus in rhizosphere soil was determined by the dilution spread plate method,and the inhibition rate was up to 86.7%.The application of ARC-BBBE in the significant peanut-producing areas of Huang-huai-hai has effects of promoting growth,nodulation,and increasing production.At the same time,it has the effect of inhibiting and controlling soil Aspergillus flavus,which provides a new green and low-carbon way to promote the high-quality development of the peanut industry.
基金Supported by Post-doctoral Management Office of Heilongjiang Province (LBH-Z06161)Key Lab of Utilization and Protection of Black Soil (GXS08-1)
文摘Microbial inoculation agent has been widely used in waste disposal and waste recycling. In this paper, the principle of fermentation in the composting of agricultural waste and the impact of microbial inoculation agent on composting were reviewed.The research and the application of microbial inoculation agent were also introduced. Based on the trend of the research, the promising prospect of microbial inoculation agent was discussed.
基金Sponsored by Hunan Provincial Pig Industry Technology SystemHunan Provincial Program of Agricultural Science and Technology(2012-193)
文摘To explore the influence of microbial agems on the decomposition of aging dunnage of the fermentation bed, this paper took the aging dunnage as the raw materials, obtained microbial strains of different types through isolation and purification, chose dominant groups to make compound microbial agents, and adopted composting decomposition experiment. The results showed that Bacillus subtilis of different ratios was added, Trichoderma koningii and Thermo actinomycetaceac could promote the decomposition of aging dunnage, especially composite microbial agents （Kc：Kn：Gf = 1：1：1 ） had the best effect of decomposition, the high tem- perature was kept for 13 days. In the end of composting, degradation rate of cellulose, degradation rate of lignin, GI, and C/N were 47.6%, 30. 2%, 98.5%, and 18.5%. Bacillus coli was not detected.
基金funded by the Science and Technology Project of Nanhu District,Jiaxing City,Zhejiang Province
文摘[ Objective] The aim of this study was to develop a cheap and localized microbial agent so as to solve high cost of microbial agent for pig manure composting in Jiaxing City. [ Method] Pig manure in the experimental group and control group was inoculated with the self-developed micro- bial agent and commercial microbial agent, respectively. The manure was decomposed for 38 d, during which the indicators of compost including physical properties, temperature, pH value, water content, organic matter, dissolved nitrogen, carbon nitrogen ratio and germination rate were studied. [ Result] The water content in the experimental group declined to 26.10% after 33 d of compost, meeting the standard upper limitation of 30% for maturity. By comparison, the water content in the control group was slightly higher than 30% even after 38 d. The germination rate of seeds fertilized with the experimental manure compost met the standard for maturity on Day 28, while that in the control group met the standard for maturity on Day 35. When the composting was finished, the ratio of total carbon to total nitrogen in the pig manure was 14.64 and 16.43 respective- ly in the experimental and control group, and the organic matter content was about 45% for both. All these indexes could meet the standards for or- ganic fertilizer products. [ Conclusion] The self-developed microbial agent can moot the requirements for pig manure composting, and it can shorten the composting time by 5 -8 d compared with the commercial agent. In addition, the fertilizer product composted by the self-developed microbial a qent has lower water content and thereby is much more beneficial for preservation.
基金Supported by the National Science and Technology Project of Water Pollution Control and Management(2012ZX07202-009-002)
文摘For the control of environment pollution caused by livestock and poultry manure, four microbial strains conducive to aerobic composting were selected and mixed into four compound microbial agents, and effects of different compound microbial agents on aerobic composting of cow manure were studied from aspects of changes in temperature, pH, water content and C/N during the composting process. The results show that microbial agent M2 has the best effect for aerobic composting of cow manure, so microbial agent M2 has broad popularization and application prospect in livestock and poultry farms in low-temperature areas of Northeast China.
基金Supported by Edible Fungus Industry Innovation Team Projects of Shandong Agricultural Industry Research System(SDAIT-11-011-08)
文摘Single or mixed use ofAgaricus bisporus residue and microbial agent had better control effect on cucumber root-knot nematode disease in greenhouse. The results showed that the control effect of single use of A. b/sporus residue was 32.9% - 34.7%, and the yield increasing rate was 2.1% - 8.7% ; the control effect of mixed use ofA. b/sporus residue and microbial agent was 59. 1% - 63. 6%, and yield increasing rate was 2.6% - 3.5%. The experimental dose had no ad- verse effects on soil physical and chemical properties. The mixed use of A. b/sporus residue and microbial agent was one of the effective ways to control root-knot nematode disease.
文摘In order to clarify the influence of microbial agents on kitchen waste and rice straw composting, an aerobic composting experiment was conducted by setting three kinds of combined bacterial agents to study the temperature change in the composting, and pH value, nutrient contents, C/N and heavy metal content after composting through. The three kinds of combined bacterial agents were as follows:B1 with effective strains: Bacillus subtilis, yeast and Trichoderma sp.;B2 with effective strains: Bacillus amyloliquefaciens, yeast and lactic acid bacteria;B3 with effective strains: Bacillus subtilis, yeast and lactic acid bacteria. Results showed that the addition of microbial agents had signifcant effects on temperature change,nitrogen and phosphorus content and C/N of the compost. T1, T2, and T3 treatments lasted for 8, 5 and 4 d in the thermophilic phase above 60℃, respectively. The total nitrogen content of each treatment was 14.90, 15.50 and 13.80 g/kg respectively after composting. The total phosphorus content of each treatment was 4.87, 4.17 and 3.70g/kg respectively at the end of composting. The C/N of each treatment was 20.94,22.63, and 22.65 respectively at the end of composting. The application effect of B1bacteria agent on the composting of kitchen waste and rice straw was better.
文摘Several quinolino-benzoxaborole derivatives have been prepared to start from aminobenzoxaboroles. These derivatives have been evaluated for their anti-cancer activity on human and murine cancer cell lines and based on their relative non-toxicity, these compounds were further evaluated for their antibacterial activity against E. coli, B. subtilis, and M. smegmatis. The synthesized compounds were also evaluated for antifungal activity in C. albicans and C. neoformans.
文摘The present study sought to assess the rational use of antimicrobial agents in a Brazilian intensive care unit (ICU) and its association with antimicrobial resistance in elderly patients admitted to the unit. Results: Choice of empiric and sensitivity-guided therapy was inadequate in > 80% and 59% of cases respectively. Inadequate antimicrobial therapy, whether empiric or sensitivity-guided, was positively correlated with bacterial resistance (r = 0.316;p = 0.001). Sensitivity testing revealed a 46.5% resistance rate to eight out of the ten most commonly used antibiotics. Multiple drug-resistant organisms were found in 40.8% of patients. A significant increase was observed in the number of multidrug-resistant samples between 2006/2007 and 2008 (r = 0.41, p = 0.006), (r = 0.598, p = 0.001), (r = 0.688, p = 0.00). Conclusion: We found a high rate of antibiotic misuse in the study sample. Inadequate therapy was correlated with resistance to antimicrobial agents.
文摘Agricultural areas of land are deteriorating every day owing to population increase, rapid urbanization, and industrialization. To feed today’s huge populations, increased crop production is required from smaller areas, which warrants the continuous application of high doses of inorganic fertilizers to agricultural land. These cause damage to soil health and, therefore, nutrient imbalance conditions in arable soils. Under these conditions, the benefits of microbial inoculants (such as Actinobacteria) as replacements for harmful chemicals and promoting ecofriendly sustainable farming practices have been made clear through recent technological advances. There are multifunctional traits involved in the production of different types of bioactive compounds responsible for plant growth promotion, and the biocontrol of phytopathogens has reduced the use of chemical fertilizers and pesticides. There are some well-known groups of nitrogen-fixing Actinobacteria, such as Frankia, which undergo mutualism with plants and offer enhanced symbiotic trade-offs.In addition to nitrogen fixation, increasing availability of major plant nutrients in soil due to the solubilization of immobilized forms of phosphorus and potassium compounds, production of phytohormones, such as indole-3-acetic acid, indole-3-pyruvic acid, gibberellins, and cytokinins, improving organic matter decomposition by releasing cellulases, xylanase, glucanases, lipases, and proteases, and suppression of soil-borne pathogens by the production of siderophores, ammonia, hydrogen cyanide, and chitinase are important features of Actinobacteria useful for combating biotic and abiotic stresses in plants.The positive influence of Actinobacteria on soil fertility and plant health has motivated us to compile this review of important findings associated with sustaining plant productivity in the long run.
文摘Marine sediment samples were collected from the coastal areas of Southern India, particularly in Kanyakumari District. Twenty-eight different fungal strains were isolated. The screening of fungi from marine sediment was done to isolate a potent fungus that can produce bioactive compounds for biomedical applications. Only three strains viz Trichoderma gamsii SP4, Talaromyces flavus SP5 and Aspergillus oryzae SP6 were screened for further studies. The intracellular bioactive compounds were extracted using solvent extraction method. The crude extracts were tested for its anti-microbial and anti-cancer properties and analytically characterized using Gas Chromatography Mass Spectrometry(GC-MS). All the three extracts were active, but the extract from T. flavus SP5 was found to be more active against various human pathogens, viz., Pseudomonas aeruginosa ATCC 27853(17.8 ± 0.1), Escherichia coli ATCC 52922(18.3 ± 0.3), and Candida tropicalis ATCC 750(17.7 ± 0.4). It also exhibited cytotoxic activity against HEp2 carcinoma cell line with the LC_(50) value of 25.7 μg·mL^(-1). The GC-MS data revealed the presence of effective bioactive compounds. These results revealed that the extract from isolated fungus T. flavus SP5 acted as a potent antimicrobial, antifungal, and anticancer agent, providing basic information on the potency of marine fungi towards biomedical applications; further investigation may lead to the development of novel anticancer drugs.
文摘The relative toxicity of 48 anilines using the Tetrahymena pyriformis population growth characteristics IGC50 （concentration causing 50% growth inhibition）, available in the literature, was studied. At first, the entire data set was randomly split into a training set （31 chemicals） used to establish the QSAR model, and a test set （17 chemicals） for statistical external validation. A biparametric model was developed using, as independent variables, 3D theoretical descriptors derived from DRAGON software. The GA-MLR （genetic algorithm variable subset selection） procedure was performed on the trainingset by the software mobydigs using the OLS （ordinary least squares） regression method, and GA（genetic algorithm）-VSS（variable subset selection） by maximising the cross-validated explained variance （Q^2Loo）＇ The obtained model was examined for robustness （Q^2LOOcross-validation, Y-scrambling） and predictive ability through both internal （Q^2LM0, bootstrap） and external validation （Q^2ext） methods. Descriptors included in the QSAR model indicated that log/GC^-150 value was related to molecular size and shape, and interaction of molecule with its surrounding medium or its target. Moreover, the applicability domain of the model was discussed.
文摘Response surface methodology and central composite rotatable design （CCRD） for K = 3 were used to investigate the combined effect of blanching time （0-1 min）, processing time （10-30 min） and sodium metabisulphite （Na2S205） salt concentration （0%-2%） on vitamin C content, hardness （texture）, microbial count and color intensity of green pepper （Capsicum sinensis） during canning. Blanching, processing time and sodium metabisulphite （Na2S205） salt concentration all had variable effects on the vitamin C, microbial quality and sensory characteristics of the canned green peppers. Significant （P 〈 0.05） interactions were noted between all the factors with high regression coefficients （78.7%-97.0%）. Increasing processing time caused significant decreases in vitamin C and microbial load of the product. However, salt concentration had only marginal and insignificant effect on the vitamin C content of the canned product. Sensory evaluation on the product showed that both the pre-processing conditions and of blanching and salt concentrations, and the processing time had varied effects on the color and hardness of the products. Hardness of the canned products generally decreased with increasing processing time and blanching time, while only minimal and insignificant effects were noted with blanching time. Increasing blanching time caused significant increasing retention of the dark green color of the peppers with only slight but insignificant increases noted with processing time, while increases in salt concentration consistently reduced the dark green color of the products. The optimum pre-processing and processing conditions that yielded products with high preference and consumer-acceptability were： blanching time of 0 min, processing time of 10 min and sodium metabisulphite concentration of 0.2%.
