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Soybean(Glycine max)rhizosphere organic phosphorus recycling relies on acid phosphatase activity and specific phosphorusmineralizing-related bacteria in phosphate deficient acidic soils
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作者 Qianqian Chen Qian Zhao +9 位作者 Baoxing Xie Xing Lu Qi Guo Guoxuan Liu Ming Zhou Jihui Tian Weiguo Lu Kang Chen Jiang Tian Cuiyue Liang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第5期1685-1702,共18页
Bacteria play critical roles in regulating soil phosphorus(P) cycling. The effects of interactions between crops and soil P-availability on bacterial communities and the feedback regulation of soil P cycling by the ba... Bacteria play critical roles in regulating soil phosphorus(P) cycling. The effects of interactions between crops and soil P-availability on bacterial communities and the feedback regulation of soil P cycling by the bacterial community modifications are poorly understood. Here, six soybean(Glycine max) genotypes with differences in P efficiency were cultivated in acidic soils with long-term sufficient or deficient P-fertilizer treatments. The acid phosphatase(AcP) activities, organic-P concentrations and associated bacterial community compositions were determined in bulk and rhizosphere soils. The results showed that both soybean plant P content and the soil AcP activity were negatively correlated with soil organic-P concentration in P-deficient acidic soils. Soil P-availability affected the ɑ-diversity of bacteria in both bulk and rhizosphere soils. However, soybean had a stronger effect on the bacterial community composition, as reflected by the similar biomarker bacteria in the rhizosphere soils in both P-treatments. The relative abundance of biomarker bacteria Proteobacteria was strongly correlated with soil organic-P concentration and AcP activity in low-P treatments. Further high-throughput sequencing of the phoC gene revealed an obvious shift in Proteobacteria groups between bulk soils and rhizosphere soils, which was emphasized by the higher relative abundances of Cupriavidus and Klebsiella, and lower relative abundance of Xanthomonas in rhizosphere soils. Among them, Cupriavidus was the dominant phoC bacterial genus, and it was negatively correlated with the soil organic-P concentration. These findings suggest that soybean growth relies on organic-P mineralization in P-deficient acidic soils, which might be partially achieved by recruiting specific phoCharboring bacteria, such as Cupriavidus. 展开更多
关键词 organic phosphorus acid phosphatase SOYBEAN bacterial community phoC-harboring bacteria RHIZOSPHERE
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Nanomotion of bacteria to determine metabolic profile
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作者 S.N.Pleskova E.V.Lazarenko +4 位作者 N.A.Bezrukov R.N.Kriukov A.V.Boryakov M.E.Dokukin S.I.Surodin 《Nanotechnology and Precision Engineering》 EI CAS CSCD 2024年第1期1-9,共9页
In addition to their visible motion such as swimming(e.g.,with the help offlagella),bacteria can also exhibit nanomotion that is detectable only with highly sensitive instruments,and this study shows that it is possibl... In addition to their visible motion such as swimming(e.g.,with the help offlagella),bacteria can also exhibit nanomotion that is detectable only with highly sensitive instruments,and this study shows that it is possible to detect bacterial nanomotion using an AFM detection system.The results show that the nanomotion characteristics depend on the bacterial strain,and that nanomotion can be used to sense the metabolic activity of bacteria because the oscillations are sensitive to the food preferences of the bacteria and the type of surrounding medium. 展开更多
关键词 Nanomotion bacteria CANTILEVER OSCILLATION Atomic force microscopy METABOLISM
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Insight into the spoilage heterogeneity of meat-borne bacteria isolates with high-producing collagenase
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作者 Haodong Wang Liangting Shao +3 位作者 Jinhao Zhang Xinglian Xu Jianjun Li Huhu Wang 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1402-1409,共8页
Chilled chicken is inevitably contaminated by microorganisms during slaughtering and processing,resulting in spoilage.Cutting parts of chilled chicken,especially wings,feet,and other skin-on products,are abundant in c... Chilled chicken is inevitably contaminated by microorganisms during slaughtering and processing,resulting in spoilage.Cutting parts of chilled chicken,especially wings,feet,and other skin-on products,are abundant in collagen,which may be the primary target for degradation by spoilage microorganisms.In this work,a total of 17 isolates of spoilage bacteria that could secrete both collagenase and lipase were determined by raw-chicken juice agar(RJA)method,and the results showed that 7 strains of Serratia,Aeromonas,and Pseudomonas could significantly decompose the collagen ingredients.The gelatin zymography showed that Serratia liquefaciens(F5)and(G7)had apparent degradation bands around 50 kDa,and Aeromonas veronii(G8)and Aeromonas salmonicida(H8)had a band around.65 and 95 kDa,respectively.The lipase and collagenase activities were detected isolate-by-isolate,with F5 showing the highest collagenase activity.For spoilage ability on meat in situ,F5 performed strongest in spoilage ability,indicated by the total viable counts,total volatile basic nitrogen content,sensory scores,lipase,and collagenase activity.This study provides a theoretical basis for spoilage heterogeneity of strains with high-producing collagenase in meat. 展开更多
关键词 bacteria Chilled chicken HETEROGENEITY COLLAGENASE SPOILAGE
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Allergen degradation of bee pollen by lactic acid bacteria fermentation and its alleviatory effects on allergic reactions in BALB/c mice
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作者 Shuting Yin Qiangqiang Li +5 位作者 Yuxiao Tao Enning Zhou Kun Wang Wanwen Chen Xiangxin Li Liming Wu 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期349-359,共11页
Food allergy as a global health problem threatens food industry.Bee pollen(BP)is a typical food with allergenic potentials,although it performs various nutritional/pharmacological functions to humans.In this study,lac... Food allergy as a global health problem threatens food industry.Bee pollen(BP)is a typical food with allergenic potentials,although it performs various nutritional/pharmacological functions to humans.In this study,lactic acid bacteria(LAB)were used to ferment Brassica napus BP for alleviating its allergenicity.Four novel allergens(glutaredoxin,oleosin-B2,catalase and lipase)were identified with significant decreases in LAB-fermented BP(FBP)than natural BP by proteomics.Meanwhile,metabolomics analysis showed significant increases of 28 characteristic oligopeptides and amino acids in FBP versus BP,indicating the degradation of LAB on allergens.Moreover,FBP showed alleviatory effects in BALB/c mice,which relieved pathological symptoms and lowered production of allergic mediators.Microbial high-throughput sequencing analysis showed that FBP could regulate gut microbiota and metabolism to strengthen immunity,which were closely correlated with the alleviation of allergic reactivity.These findings could contribute to the development and utilization of hypoallergenic BP products. 展开更多
关键词 Alleviatory effects Lactic acid bacteria fermentation Bee pollen allergen Gut microbiota Host metabolism
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Antiseptic Efficacy of A Soap Made from Biosurfactants Isolated from Bacillus and Lactobacillus against Pathogenic Bacteria
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作者 Frédéric Yannick Okouakoua Christian Aimé Kayath +10 位作者 Nicaise Saturnin Mokémiabeka Varelle Bervanie Ngala Elenga Digne Nedjea N’goma-Mona Ndelani Nkalla Lambi Sandra Paola Elenga Wilson Christ Dieuveil Bayakissa Malanda Rodinet Tsana Junior Patrick Sergy Bissoko1 Moïse Doria Kaya-Ongoto Duchel Jeanedvi Kinavouidi Etienne Nguimbi 《Advances in Microbiology》 CAS 2024年第1期31-58,共28页
The aim of our study was to use a biosurfactant produced by Bacillus and Lactobacillus isolates as an antiseptic in the formulation of local soap. A total of 60 isolates were characterized by microbiological technique... The aim of our study was to use a biosurfactant produced by Bacillus and Lactobacillus isolates as an antiseptic in the formulation of local soap. A total of 60 isolates were characterized by microbiological techniques (30 Bacillus and 30 Lactobacillus) and the ability to produce biosurfactants was demonstrated by a hydrocarbon emulsification index (E24). The emulsification indexes (E24) varied from 9% to 100% for Bacillus and from 33% to 100% for Lactobacillus as well. The antagonistic assay showed that biosurfactants were able to inhibit the formation of biofilms and growth of pathogens such as Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus cereus, Salmonella typhirium, Shigella boydii and Proteus mirabilis. The biosurfactant consortium (BioC) from Bacillus consortium and from Lactobacillus was able to inhibit biofilm formation and the pathogens growth. The BioC was stable to alkaline pH and the temperatures stability of Biosurfactant was ranging from 50°C to 90°C. The soap was made by the cold saponification process using one biosurfactant consortium formulated. This soap has a pH of 10 and showed good cleaning power and good foam stability. Similarly, the soap showed good antiseptic power and disinfection power against all pathogens tested. Handwashing is critical to preventing disease transmission. The persistence of pathogens in waste water was evaluated. The BioS produced showed good disinfection power against all pathogens tested. The valor of reduction on the hands and in the waste water was significantly more than compared to the control soaps used. This soap could be used in the prevention, fighting, and treatment of bacterial and viral infections. 展开更多
关键词 ANTISEPTIC SOAP Biosurfactants BACILLUS LACTOBACILLUS DISINFECTION Pathogens bacteria
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Nature’s Pharmacy under Siege: Investigating Antibiotic Resistance Pattern in Endophytic Bacteria of Medicinal Plants
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作者 Bonoshree Sarkar Afroza Sultana +5 位作者 Nabila Nawar Binti Farhana Tasnim Chowdhury Sadia Afrin Mohammad Fahim Taibur Rahman Atiqur Rahman 《Advances in Microbiology》 CAS 2024年第4期183-208,共26页
Antibiotic resistance poses a significant global health threat, necessitating a thorough understanding of its prevalence in various ecological contexts. Medicinal plants, renowned for their therapeutic properties, hos... Antibiotic resistance poses a significant global health threat, necessitating a thorough understanding of its prevalence in various ecological contexts. Medicinal plants, renowned for their therapeutic properties, host endophytic bacteria that produce bioactive compounds. Understanding antibiotic resistance dynamics in these bacteria is vital for human health and antibiotic efficacy preservation. In this study, we investigated antibiotic resistance profiles in endophytic bacteria from five medicinal plants: Thankuni, Neem, Aparajita, Joba, and Snake plant. We isolated and characterized 113 endophytic bacteria, with varying resistance patterns observed against multiple antibiotics. Notably, 53 strains were multidrug-resistant (MDR), with 14 exhibiting extensive drug resistance (XDR). Thankuni-associated bacteria displayed 44% MDR and 11% XDR, while Neem-associated bacteria showed higher resistance (60% MDR, 13% XDR). Aparajita-associated bacteria had lower resistance (22% MDR, 6% XDR), whereas Joba-associated bacteria exhibited substantial resistance (54% MDR, 14% XDR). Snake plant-associated bacteria showed 7% MDR and 4% XDR. Genus-specific distribution revealed Bacillus (47%), Staphylococcus (21%), and Klebsiella (11%) as major contributors to MDR. Our findings highlight diverse drug resistance patterns among plant-associated bacteria and underscore the complexity of antibiotic resistance dynamics in diverse plant environments. Identification of XDR strains emphasizes the severity of the antibiotic resistance problem, warranting further investigation into contributing factors. 展开更多
关键词 Antibiotic Resistance Endophytic bacteria Medicinal Plants Drug Resistance
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Effects of Inoculation with Phosphate Solubilizing Bacteria on the Physiology,Biochemistry,and Expression of Genes Related to the Protective Enzyme System of Fritillaria taipaiensis P.Y.Li
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作者 Zhifen Shi Fumei Pan +6 位作者 Xiaotian Kong Jiaqi Lang Mingyan Ye Qian Wu Guangzhi Wang Liang Han Nong Zhou 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第2期247-260,共14页
Fritillaria taipaiensis P.Y.Li is a widely used medicinal herb in treating pulmonary diseases.In recent years,its wild resources have become scarce,and the demand for efficient artificial cultivation has significantly... Fritillaria taipaiensis P.Y.Li is a widely used medicinal herb in treating pulmonary diseases.In recent years,its wild resources have become scarce,and the demand for efficient artificial cultivation has significantly increased.This article is the first to apply phosphate solubilizing bacteria isolated from the rhizosphere soil of F.taipaiensis P.Y.Li to the cultivation process of F.taipaiensis P.Y.Li.The aim is to identify suitable reference strains for the artificial cultivation and industrial development of F.taipaiensis P.Y.Li by examining the effects of various phosphate solubilizing bacteria and their combinations on photosynthesis,physiological and biochemical properties,and gene expression related to the protective enzyme system in F.taipaiensis P.Y.Li.The experiment,conducted in pots at room temperature,included a control group(CK)and groups inoculated with inorganic phosphorussolubilizing bacteria:W1(Bacillus cereus),W2(Serratia plymuthica),W12(Bacillus cereus and Serratia plymuthica),and groups inoculated with organophosphorus-solubilizing bacteria:Y1(Bacillus cereus),Y2(Bacillus cereus),Y12(Bacillus cereus and Bacillus cereus),totaling seven groups.Compared to CK,most growth indices in the bacterial addition groups showed significant differences,with W12 achieving the highest values in all indices except the leaf area index.The content of photosynthetic pigments,photosynthetic parameters,and osmoregulatory substances increased variably in each bacterial treatment group.W12 exhibited the highest content of chlorophyll a and soluble protein,while W1 had the highest free proline content.The activities of peroxidase(POD),superoxide dismutase(SOD),and catalase(CAT)in all inoculated groups were higher than in CK,with significant changes in SOD and CAT activities.The malondialdehyde(MDA)content in all inoculated groups was lower than in CK,with Y12 being the lowest,at approximately 30%of CK.Gene expression corresponding to these three enzymes also increased variably,with POD expression in Y2 being the highest at 2.73 times that of CK.SOD and CAT expression in Y12 were the highest,at 1.84 and 4.39 times that of CK,respectively.These results indicate that inoculating phosphate solubilizing bacteria can enhance the growth of F.taipaiensis P.Y.Li,with the mixed inoculation groups W12 and Y12 demonstrating superior effects.This lays a theoretical foundation for selecting bacterial fertilizers in the cultivation process of F.taipaiensis P.Y.Li. 展开更多
关键词 Fritillaria taipaiensis P.Y.Li phosphate solubiliozing bacteria photosynthesis physiology and biochemistry protective enzymes
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The Preliminary Study on Screening and Application of Phthalic Acid-Degrading Bacteria
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作者 Honghao Zhang Lin Yang +3 位作者 Rubing Xu Yuxiao Sun Yong Yang Yanyan Li 《Advances in Microbiology》 CAS 2024年第4期226-239,共14页
Phthalic acid is a main pollutant, which is also an important reason for the continuous cropping effect of tobacco. In order to degrade the phthalic acid accumulated in the environment and relieve the obstacle effect ... Phthalic acid is a main pollutant, which is also an important reason for the continuous cropping effect of tobacco. In order to degrade the phthalic acid accumulated in the environment and relieve the obstacle effect of tobacco continuous cropping caused by the accumulation of phthalic acid in the soil. In this study, phthalate degrading bacteria B3 is screened from continuous cropping tobacco soil. The results of biochemical identification and 16sDNA comparison show that the homology between degrading bacterium B3 and Enterobacter sp. is 99%. At the same time, the growth of Enterobacter hormaechei subsp. B3 and the degradation of phthalic acid under different environmental conditions are studied. The results show that the environment with a temperature of 30˚C, PH of 7, and inoculation amount of not less than 1.2%, which is the optimal growth conditions for Enterobacter sp. B3. In an environment with a concentration of phthalic acid not exceeding 500 mg/L, Enterobacter sp. B3 has a better effect on phthalic acid degradation, and the degradation rate can reach 77% in 7 d. The results of indoor potting experiments on tobacco show that the degradation rate of phthalic acid by Enterobacter B3 in the soil is about 45%, which can reduce the inhibitory effect of phthalic acid on the growth of tobacco seedlings. This study enriches the microbial resources for degrading phthalic acid and provides a theoretical basis for alleviating tobacco continuous cropping obstacles. 展开更多
关键词 Phthalic Acid Degrading bacteria Rhizosphere Soil
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Relationship between nutritional therapy and beneficial bacteria ratio in severe disease
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作者 Kento Nakayama Hiroyuki Koami Yuichiro Sakamoto 《Journal of Acute Disease》 2024年第1期26-30,共5页
Objective:To evaluate relationship between changes in the beneficial bacteria in intensive care unit(ICU)patients and nutritional therapy type.Methods:Ten patients aged≥18 years admitted to the ICU between January an... Objective:To evaluate relationship between changes in the beneficial bacteria in intensive care unit(ICU)patients and nutritional therapy type.Methods:Ten patients aged≥18 years admitted to the ICU between January and December 2020,were included.Good enteral nutrition was defined as early achievement of target calorie intake through enteral feeding.The ratio of beneficial bacteria at the first and second bowel movements after each patient’s admission was calculated and the patients were classified into the increase or decrease group.Among all patients,five each were in the increase and decrease groups.We investigated patient background,changes in sequential organ failure assessment(SOFA)and acute physiology and chronic health evaluation(APACHE)Ⅱscores,nutritional doses or methods,and clinical outcomes.Results:No relationship was found between changes in the ratio of beneficial bacteria and changes in SOFA/APACHEⅡscores at the time of admission.The rate of good enteral nutrition was significantly higher in the increase group than in the decrease group(4/5 vs.0/5,P=0.01).Conclusions:An increase in beneficial bacteria may be significantly related to the early establishment of enteral nutrition.In the future,accumulating cases may make it possible to establish a new nutritional strategy for critically ill patients from an intestinal microbiota perspective. 展开更多
关键词 Beneficial bacteria Enteral nutrition Parenteral nutrition Intensive care unit Good enteral nutrition Severe disease Nutritional therapy
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Synthesis of Silver Nanoparticles from Honeybees and Its Antibacterial Potential
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作者 Akamu J. Ewunkem Niore’s Johnson +3 位作者 A’lyiha F. Beard Ilunga Tshimanga Brittany Justice Jeffery Meixner 《Open Journal of Medical Microbiology》 2024年第1期77-92,共16页
Honeybees (Apis mellifera) are important pollinators of flowering plants and agricultural crops contributing annually to billions of dollars in revenues to crop production. Honeybees have an average lifespan between 8... Honeybees (Apis mellifera) are important pollinators of flowering plants and agricultural crops contributing annually to billions of dollars in revenues to crop production. Honeybees have an average lifespan between 8 weeks to 5 years. Dead honeybees are abundantly available in beehives and can be utilized as an alternative source to synthesize nanoparticles. In recent years, biologically synthesized nanoparticles have been preferred over their chemical counterparts. However, honeybee-based-green synthesis of nanoparticles has not been explored yet. Herein, we report the biosynthesis of silver nanoparticles from honeybees and its antibacterial activity. The synthesis of silver nanoparticles was monitored visually through a gradual change in color. Furthermore, the biosynthesized nanoparticles were confirmed and characterized by UV-visible spectroscopy. Scanning Electron Microscope was utilized to analyze the average size and morphologies of the biosynthesized nanoparticles. Subsequently, the antibacterial potential of the biosynthesized silver nanoparticles was tested against selected Gram-positive and Gram-negative bacterial strains. It was found that a distinct color change from yellow to brown in the reaction solution suggested the formation of silver nanoparticles. The biosynthesized nanoparticles exhibited absorption maxima at 430 nm. The SEM analysis confirmed the spherical and cuboidal shape of the biosynthesized silver nanoparticles with a size range between 10 - 40 nm. Furthermore, the biosynthesized silver nanoparticles exhibited strong antimicrobial potential against tested Gram-positive and Gram-negative bacteria strains by aggregating on the cell surface. This study showcases the biomedical and agricultural applications of biosynthesized silver nanoparticles from honeybee wings. . 展开更多
关键词 HONEYBEE bacteria Green Synthesis Nanoparticles ANTIMICROBIAL
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Characterisation of the Bacteria and Archaea Community Associated with Wild Oysters, At Three Possible Restoration Sites in the North Sea
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作者 Natacha M. S. Juste-Poinapen Yang Lu +2 位作者 Blanca Bolaños De Hoyos George C. Birch Camille Saurel 《Open Journal of Marine Science》 2024年第2期19-40,共22页
With 85% of the global oyster reefs destroyed, there is an urgent need for large scale restoration to benefit from the ecosystem services provided by biogenic oyster reefs and their associated biodiversity, including ... With 85% of the global oyster reefs destroyed, there is an urgent need for large scale restoration to benefit from the ecosystem services provided by biogenic oyster reefs and their associated biodiversity, including microorganisms that drive marine biogeochemical cycles. This experiment established a baseline for the monitoring of the bacterial and archaeal community associated with wild oysters, using samples from their immediate environment of the Voordelta, with cohabiting Crassostrea gigas and Ostrea edulis, Duikplaats with only C. gigas attached to rocks, and the Dansk Skaldyrcentre, with no onsite oysters. The microbial profiling was carried out through DNA analysis of samples collected from the surfaces of oyster shells and their substrate, the sediment and seawater. Following 16S rRNA amplicon sequencing and bioinformatics, alpha indices implied high species abundance and diversity in sediment but low abundance in seawater. As expected, Proteobacteria, Bacteroidetes, Firmicutes and Thaumarchaeota dominated the top 20 OTUs. In the Voordelta, OTUs related to Colwellia, Shewanella and Psychrobium differentiated the oysters collected from a reef with those attached to rocks. Duikplaats were distinct for sulfur-oxidizers Sulfurimonas and sulfate-reducers from the Sva 0081 sediment group. Archaea were found mainly in sediments and the oyster associated microbiome, with greater abundance at the reef site, consisting mostly of Thaumarchaeota from the family Nitrosopumilaceae. The oyster free site displayed archaea in sediments only, and algal bloom indicator microorganisms from the Rhodobacteraceae, Flavobacteriaceae family and genus [Polaribacter] huanghezhanensis, in addition to the ascidian symbiotic partner, Synechococcus. This study suggests site specific microbiome shifts, influenced by the presence of oysters and the type of substrate. 展开更多
关键词 Oyster Reefs MICROBIOME Marine bacteria Marine Archaea RESTORATION
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Performance Parameters:Demobilization Antibiotic Resistant Bacteria(ARB)and Carrying Genes(ARG)in Wastewater Disinfection
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作者 Solange Kazue Utimura Denise Crocce Romano Espinosa +2 位作者 Marcio Luís Busi da Silva Elisabete de Santis Braga Pedro Jose Alvarez 《Journal of Environmental Science and Engineering(B)》 2024年第1期1-8,共8页
The UV irradiation is used for removing Antibiotic Resistant Bacteria(ARB)and Antibiotic Resistance Genes(ARG)from wastewater treatment.Bacteriophages are viruses that infect within bacteria,are recognized for bacteri... The UV irradiation is used for removing Antibiotic Resistant Bacteria(ARB)and Antibiotic Resistance Genes(ARG)from wastewater treatment.Bacteriophages are viruses that infect within bacteria,are recognized for bacterial control.The influence of some parameters in quantification and performance influencing of pathogen demobilization could be considered in disinfection of wastewater.The comparison of Polyvalent phage(NE1)versus Coliphage(NE4)in suppressing a bacterium Escherichia coli(NDM-1:b-lactam-resistant)with UV irradiation was observed the efficacy in reduction of cells in the disinfection and parameter process.The results with the effect of UV-C irradiation on NDM-1 infected with 1%of NE4 showed a decrease of cells from 8×10^(6)to 2×10^(5)in 60 min with UV-C dose.The NDM1(E.coli)was infected with 1%of NE4(Polyvalent Phage)under magnetic stirring for 1 h,the cells count was 8×10^(6).After 1 h in UV-C e×posure,the cells number reached 3×10^(5).The NDM1 that was e×posed in 1 h of UV-C irradiation and then was infected with 1%of NE4.Cells counting were done 24 h after this procedure.These cells were e×posed in UV-C and showed a reduction in the number of cells from 1×10^(8)to 4×10^(5)after 60 min.The results indicate that bacteriophages can mitigate bacteria species,and combined the conventional water disinfection technologies that can support the microbial safety control strategies. 展开更多
关键词 Antibiotic Resistant bacteria(ARB) Antibiotic Resistance Genes(ARG) wastewater treatment DISINFECTION Escherichia coli(E.coli).
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Dynamic Analysis of an Algae-Bacteria Ecological Model
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作者 Gaopeng Sun Hengguo Yu 《Journal of Applied Mathematics and Physics》 2024年第1期362-382,共21页
In the paper, under the framework of exploring the interaction between algae and bacteria, an algae-bacteria ecological model was established to analyze the interaction mechanism and growth coexistence mode between al... In the paper, under the framework of exploring the interaction between algae and bacteria, an algae-bacteria ecological model was established to analyze the interaction mechanism and growth coexistence mode between algicidal bacteria and algae. Firstly, mathematical work mainly provided some threshold conditions to ensure the occurrence of transcritical bifurcation and saddle-node bifurcation, which could provide certain theoretical support for selecting key ecological environmental factors and numerical simulations. Secondly, the numerical simulation work dynamically displayed the evolution process of the bifurcation dynamic behavior of the model (2.1) and the growth coexistence mode of algae and algicidal bacteria. Finally, it was worth summarizing that intrinsic growth rate and combined capture effort of algae population had a strong influence on the dynamic behavior of the model (2.1). Furthermore, it must also be noted that transcritical bifurcation and saddle-node bifurcation were the inherent driving forces behind the formation of steady-state growth coexistence mode between algicidal bacteria and algae. In summary, it was hoped that the results of this study would contribute to accelerating the study of the interaction mechanism between algicidal bacteria and algae. 展开更多
关键词 ALGAE Algicidal bacteria Transcritical Bifurcation Saddle-Node Bifurcation Coexistence Mode
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Isolation and Identification of Houttuynia cordata Endophytic Bacteria and Study of Antibiotic Activity
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作者 Kaifeng WANG Shunxin YANG Zhannan YANG 《Medicinal Plant》 CAS 2023年第3期1-4,共4页
[Objectives]To further explore the resources of biocontrol strains and provide new options for the control of pathogenic bacteria.[Methods]Houttuynia cordata endophytic bacteria were isolated and identified,and the an... [Objectives]To further explore the resources of biocontrol strains and provide new options for the control of pathogenic bacteria.[Methods]Houttuynia cordata endophytic bacteria were isolated and identified,and the antibiotic activity was explored.[Results]There are 8 strains(H1-H8)of endophytic bacteria isolated from the healthy plants of H.cordata,which had an antagonistic effect on the pathogenic bacteria.According to the gene sequence,the 8 strains were identified as Stenotrophomonas,Pseudomonas,and Bacillus,which strongly inhibited Colletotrichum(HC1),Fusarium(HC2),and Rhizoctonia(HC5)of H.cordata.On the PDA culture dish,the inhibition diameter of the 8 strains on Colletotrichum,Fusarium,and Rhizoctonia was 6,8,and 5 mm,respectively.[Conclusions]Pathogenic bacteria and endophytic bacteria inoculated with H.cordata seedlings showed that endophytic bacteria have certain antagonistic activity,and have the potential for development and application. 展开更多
关键词 Houttuynia cordata Endophytic bacteria Pathogenic bacteria Antibiotic
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Effects of planting patterns plastic film mulching on soil temperature,moisture, functional bacteria and yield of winter wheat in the Loess Plateau of China 被引量:1
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作者 ZHAO Xiao-dong QIN Xiao-rui +2 位作者 LI Ting-liang CAO Han-bing XIE Ying-he 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第5期1560-1573,共14页
The yield of winter wheat is hindered by drought and low temperature in the Loess Plateau of China.Two common mulching methods to conserve soil moisture,ridge furrows with plastic film mulching (RP) and flat soil surf... The yield of winter wheat is hindered by drought and low temperature in the Loess Plateau of China.Two common mulching methods to conserve soil moisture,ridge furrows with plastic film mulching (RP) and flat soil surfaces with plastic film mulching (FP) are helpful for wheat production.Our previous study indicated that FP could improve wheat yield more effectively than RP,but the reason remains unclear.The effect of mulching method on functional bacteria also needs to be further studied.In this study,winter wheat was employed to evaluate the impacts of mulching method on soil temperature,moisture content,microorganisms and grain yield.The results showed that FP had a warming effect when the soil temperature was low and a cooling effect when the temperature was too high.However,the ability to regulate soil temperature in the RP method was unstable and varied with year.The lowest negative accumulated soil temperature was found in the FP treatment,which was 20–89 and 43–99%lower than that of the RP and flat sowing with non-film mulching control (NP) treatments,respectively.Deep soil moisture was better transferred to topsoil for wheat growth in the FP and RP treatments than the NP treatment,which made the topsoil moisture in the two treatments (especially FP) more sufficient than that in the NP treatment during the early growing stage of wheat.However,due to the limited water resources in the study area,there was almost no difference between treatments in topsoil water storage during the later stage.The wheat yield in the FP treatment was significantly higher,by 12–16and 23–56%,respectively,than in the RP and NP treatments.Significant positive correlations were observed among the negative accumulated soil temperature,spike number and wheat yield.The Chao1 and Shannon indices in the RP treatment were 17 and 3.9%higher than those in the NP treatment,respectively.However,according to network relationship analysis,the interspecific relationships of bacteria were weakened in the RP treatment.Phosphorus solubilizing,ammonification and nitrification bacteria were more active in the RP than in the FP treatment,and microbes with nitrate reduction ability and plant pathogens were inhibited in the RP treatment,which improved nutrient availability and habitat for wheat. 展开更多
关键词 winter wheat soil temperature MOISTURE functional bacteria GRAIN YIELD
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The succession of fecal bacterial community and its correlation with the changes of serum immune indicators in lambs from birth to 4 months 被引量:1
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作者 YIN Xue-jiao JI Shou-kun +5 位作者 DUAN Chun-hui TIAN Pei-zhi JU Si-si YAN Hui ZHANG Ying-jie LIU Yue-qin 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第2期537-550,共14页
Early bacterial colonization and succession within the gastrointestinal tract have been suggested to be crucial in the development of host immunity.In this study,we have investigated the changes in live weight and con... Early bacterial colonization and succession within the gastrointestinal tract have been suggested to be crucial in the development of host immunity.In this study,we have investigated the changes in live weight and concentrations of selected serum parameters in relation to their fecal bacterial communities as determined by high throughput sequencing of the 16S r RNA gene over the same period in lambs.The results showed that lambs’growth performance,the serum parameters,fecal bacterial community and fecal bacterial functions were all affected(P<0.05)by age of the lambs.Similarity within age groups of fecal microbiota was lower in the preweaning period and increased sharply(P<0.05)after weaning at 60 days.The similarity between the samples collected from birth to 90 days of age and those collected at 120 days of age,increased(P<0.05)sharply after 30 days of age.Some age-associated changes in microbial genera were correlated with the changes in concentrations of immune indicators,including negative(P<0.05)correlations between the relative abundance of Lachnospiraceae UCG-010,Eubacterium coprostanoligenes group,Ruminococcaceae UCG-005,Ruminococcaceae UCG-009,Ruminococcaceae UCG-013,Ruminiclostridium 6,Ruminococcaceae UCG-008,and Oscillibacter with serum concentrations of lipopolysaccharide(LPS),D-lactate dehydrogenase(DLA),immunoglobulin(IgA,IgM,and IgG),and cytokines(interleukin-1β(IL-1β),IL-6,IL-12,and IL-17),tumor necrosis factor-α(TNF-α),and the relative abundance of these genera increased from 45 days of age.In conclusion,these results suggested that the age-related abundances of particular genera were correlated with serum markers of immunity in lambs,and there might be a critical window in the period from birth to 45 days of age which provide an opportunity for potential manipulation of the fecal microbial ecosystems to enhance immune function. 展开更多
关键词 fecal bacteria establishment sheep serum parameter early life
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Ability of lactulose breath test results to accurately identify colorectal polyps through the measurement of small intestine bacterial overgrowth 被引量:1
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作者 Lan Li Xue-Yuan Zhang +5 位作者 Jin-Sheng Yu Hui-Min Zhou Yan Qin Wen-Rui Xie Wen-Jing Ding Xing-Xiang He 《World Journal of Gastrointestinal Surgery》 SCIE 2023年第6期1138-1148,共11页
BACKGROUND While colorectal polyps are not cancerous,some types of polyps,known as adenomas,can develop into colorectal cancer over time.Polyps can often be found and removed by colonoscopy;however,this is an invasive... BACKGROUND While colorectal polyps are not cancerous,some types of polyps,known as adenomas,can develop into colorectal cancer over time.Polyps can often be found and removed by colonoscopy;however,this is an invasive and expensive test.Thus,there is a need for new methods of screening patients at high risk of developing polyps.AIM To identify a potential association between colorectal polyps and small intestine bacteria overgrowth(SIBO)or other relevant factors in a patient cohort with lactulose breath test(LBT)results.METHODS A total of 382 patients who had received an LBT were classified into polyp and non-polyp groups that were confirmed by colonoscopy and pathology.SIBO was diagnosed by measuring LBTderived hydrogen(H)and methane(M)levels according to 2017 North American Consensus recommendations.Logistic regression was used to assess the ability of LBT to predict colorectal polyps.Intestinal barrier function damage(IBFD)was determined by blood assays.RESULTS H and M levels revealed that the prevalence of SIBO was significantly higher in the polyp group than in the non-polyp group(41%vs 23%,P<0.01;71%vs 59%,P<0.05,respectively).Within 90 min of lactulose ingestion,the peak H values in the adenomatous and inflammatory/hyperplastic polyp patients were significantly higher than those in the non-polyp group(P<0.01,and P=0.03,respectively).In 227 patients with SIBO defined by combining H and M values,the rate of IBFD determined by blood lipopolysaccharide levels was significantly higher among patients with polyps than those without(15%vs 5%,P<0.05).In regression analysis with age and gender adjustment,colorectal polyps were most accurately predicted with models using M peak values or combined H and M values limited by North American Consensus recommendations for SIBO.These models had a sensitivity of≥0.67,a specificity of≥0.64,and an accuracy of≥0.66.CONCLUSION The current study made key associations among colorectal polyps,SIBO,and IBFD and demonstrated that LBT has moderate potential as an alternative noninvasive screening tool for colorectal polyps. 展开更多
关键词 Lactulose breath test Colorectal polyp Small intestine bacteria overgrowth Intestinal barrier function Retrospective study
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Diversity of soil bacteria and fungi communities in artificial forests of the sandy-hilly region of Northwest China
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作者 GOU Qianqian MA Gailing +1 位作者 QU Jianjun WANG Guohua 《Journal of Arid Land》 SCIE CSCD 2023年第1期109-126,共18页
Soil erosion is a serious issue in the sandy-hilly region of Shanxi Province,Northwest China.There has been gradual improvement due to vegetation restoration,but soil microbial community characteristics in different v... Soil erosion is a serious issue in the sandy-hilly region of Shanxi Province,Northwest China.There has been gradual improvement due to vegetation restoration,but soil microbial community characteristics in different vegetation plantation types have not been widely investigated.To address this,we analyzed soil bacterial and fungal community structures,diversity,and microbial and soil environmental factors in Caragana korshinskii Kom.,Populus tomentosa Carr.,Populus simonii Carr.,Salix matsudana Koidz,and Pinus tabulaeformis Carr.forests.There were no significant differences in the dominant bacterial community compositions among the five forest types.The alpha diversity of the bacteria and fungi communities showed that ACE(abundance-based coverage estimator),Chao1,and Shannon indices in C.korshinskii forest were significantly higher than those in the other four forest types(P<0.05).Soil organic matter,total nitrogen,and urease had a greater impact on bacterial community composition,while total nitrogen,β-glucosidase,and urease had a greater impact on fungal community composition.The relative abundance of beneficial and pathogenic microorganisms was similar across all forest types.Based on microbial community composition,diversity,and soil fertility,we ranked the plantations from most to least suitable as follows:C.korshinskii,S.matsudana,P.tabulaeformis,P.tomentosa,and P.simonii. 展开更多
关键词 microbial community composition artificial forest bacteria FUNGI DIVERSITY sandy-hilly region
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Rice ferredoxin OsFd4 contributes to oxidative stress tolerance but compromises defense against blight bacteria
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作者 Minfeng Lu Jinhui Chen +5 位作者 Han Meng Guangling Mo Yunhong Liu Fengping Chen Zonghua Wang Mo Wang 《The Crop Journal》 SCIE CSCD 2023年第6期1937-1942,共6页
Ferredoxins(Fds)in plastids are the most upstream stromal electron receptors shuttling electrons to downstream metabolic systems and function in various physiological processes of dicots,but their roles in monocots’r... Ferredoxins(Fds)in plastids are the most upstream stromal electron receptors shuttling electrons to downstream metabolic systems and function in various physiological processes of dicots,but their roles in monocots’response to stresses are still unclear.In this study,the functions of OsFd4,the major non-photosynthetic type Fd in rice,were characterized under oxidative stress and Xanthomonas oryzae pv.oryzae(Xoo)infection.OsFd4-knockout mutants displayed no defects in key agronomic traits and blast resistance,but were more sensitive to hydrogen peroxide(H2O2)treatment than the wild type.Transient expression of OsFd4 alleviated H2O2-induced rice cell death,suggesting that OsFd4 contributes to rice tolerance to exogenous oxidative stress.Deletion of OsFd4 enhanced rice immune responses against Xoo.OsFd4 formed a complex in vivo with itself and OsFd1,the major photosynthetic Fd in rice,and OsFd1 transcripts were increased in leaf and root tissues of the OsFd4-knockout mutants.These results indicate that OsFd4 is involved in regulating rice defense against stresses and interplays with OsFd1. 展开更多
关键词 FERREDOXIN RICE OsFd4 Oxidative stress Blight bacteria
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3D-printed engineered bacteria-laden gelatin/sodium alginate composite hydrogels for biological detection of ionizing radiation
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作者 Ziyuan Chen Jintao Shen +8 位作者 Meng Wei Wenrui Yan Qiucheng Yan Zhangyu Li Yaqiong Chen Feng Zhang Lina Du Bochuan Yuan Yiguang Jin 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2023年第4期439-450,共12页
Nuclear safety is a global growing concern,where ionizing radiation(IR)is a major injury factor resulting in serious damage to organisms.The detection of IR is usually conducted with physical dosimeters;however,biolog... Nuclear safety is a global growing concern,where ionizing radiation(IR)is a major injury factor resulting in serious damage to organisms.The detection of IR is usually conducted with physical dosimeters;however,biological IR detection methods are deficient.Here,a living composite hydrogel consisting of engineered bacteria and gelatin/sodium alginate was 3D-printed for the biological detection of IR.Three strains of PrecA::egfp gene circuit-containing engineered Escherichia coli were constructed with IR-dependent fluorescence,and the DH5αstrain was finally selected due to its highest radiation response and fluorescence.Engineered bacteria were loaded in a series of gelatin/sodium alginate matrix hydrogels with different rheology,3D printability and bacterial applicability.A high-gelatin-content hydrogel containing 10%gelatin/1.25%sodium alginatewas optimal.The optimal living composite hydrogelwas 3D-printedwith the special bioink,which reported significant green fluorescence underγ-ray radiation.The living composite hydrogel provides a biological strategy for the detection of environmental ionizing radiation. 展开更多
关键词 3D printing ALGINATE Engineered bacteria GELATIN HYDROGEL Ionizing radiation
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