Ethylthionocarbamates (ETC), which is the most widely used as collectors in the flotation of sulfide, is known to cause serious pollution to soil and groundwater. The potential biodegradation of ETC was evaluated b...Ethylthionocarbamates (ETC), which is the most widely used as collectors in the flotation of sulfide, is known to cause serious pollution to soil and groundwater. The potential biodegradation of ETC was evaluated by applying a mixed culture of iron-reducing bacteria (IRB) enriched from tailings dam sediments. The results showed that ETC can be degraded by IRB coupled to Fe(III) reduction, both of which can be increased in the presence of anthraquinone-2,6-disulfonate (AQDS). Moreover, Fe(III)-EDTA was found to be a more favorable terminal electron acceptor compared to α-Fe2O3, e.g., within 30 d, 72% of ETC was degraded when α-Fe2O3+AQDS was applied, while it is 82.67% when Fe(III)-EDTA+AQDS is added. The dynamic models indicated that the kETC degradation was decreased in the order of Fe(III)-EDTA+AQDS〉α-Fe2O3+AQDS〉Fe(III)-EDTA〉α-Fe2O3, with the corresponding maximum biodegradation rates being 2.6, 2.45, 2.4 and 2.0 mg/(L·d), respectively, and positive parallel correlations could be observed between kFe(III) and kETC. These findings demonstrate that IRB has a good application prospect in flotation wastewater.展开更多
Iron toxicity is a major stress to rice caused by a high concentration of reduced iron, in the soil in many lowlands worldwide. To reduce iron toxicity in the West African lowlands, an investigation was performed at t...Iron toxicity is a major stress to rice caused by a high concentration of reduced iron, in the soil in many lowlands worldwide. To reduce iron toxicity in the West African lowlands, an investigation was performed at the site of the University of Ouagadougou, in pots containing an iron toxic soil from the Kou Valley (West of Burkina Faso). The experiment objective was to study the effect of mineral fertilizer on Iron Reducing Bacteria (IRB) dynamics and activity during rice cultivation, iron accumulation in rice plant and rice biomass yield under iron toxicity conditions. BOUAKE-189 and ROK-5 rice varieties, sensitive and tolerant to iron toxicity, respectively, were used for the experiment. The pots were amended with chemical fertilizers (NPK + Urea and NPK + Urea + Ca + Mg + Zn complex). Control pots without fertilization were prepared similarly. The kinetics of IRB and ferrous iron content in soil near rice roots were monitored throughout the cultural cycle using MPN and colorimetric methods, respectively. The total iron content was evaluated in rice plant using spectrometric method. Data obtained were analyzed in relation to fertilization mode, rice growth stage and rice yield using the student’s t-test and XLSTAT 2014 statistical software. The experiment revealed that NPK + Urea and NPK + Urea + Ca + Mg + Zn fertilization, decreased significantly (p < 0.0001) the number of IRB in the soil for BOUAKE-189 rice varieties. In most pots, highest IRB densities and ferrous iron content in soil were recorded from rice tillering and flowering to maturity stages, indicating that rice plants promoted microbial processes and iron reduction in soil. From the study, the NPK + Urea amendment decreased significantly ferrous iron content (p < 0.0001) in soil near BOUAKE-189 and ROK-5 rice varieties roots relatively to control pots. However, NPK + Urea + Ca + Zn + Mg amendment increased significantly ferrous iron content (p < 0.0001) in the soil near roots, Fe accumulation in plant biomass and rice yield for the two rice varieties.展开更多
Iron toxicity is one of the main edaphic constraints that hamper rice production in West African savanna and forest lowlands. Although chemical reduction processes of various types of pedogenic iron oxides could not b...Iron toxicity is one of the main edaphic constraints that hamper rice production in West African savanna and forest lowlands. Although chemical reduction processes of various types of pedogenic iron oxides could not be underestimated, the bulk of these processes can be ascribed to the specific activity of Iron-Reducing Bacteria (IRB). The reducing conditions of waterlogged lowland soils boost iron toxicity through the reduction of almost all iron into ferrous form (Fe2+), which can cause disorder in rice plant and crop yield losses. Aiming to contribute at the improvement of rice yield in Africa, an experiment was developed to evaluate the impact of subsurface drainage on IRB dynamics and activity during rice cultivation. Twelve concrete microplots with a clay-loam soil and a rice variety susceptible to iron toxicity (FKR 19) were used for the experiment. Soil in microplots was drained for 7 days (P1), 14 days (P2), and 21 days (P3), respectively. Control (T) microplots without drainage were prepared similarly. The evolution of IRB populations and the content of ferrous iron in the paddy soil and in soil near rice root were monitored throughout the cultural cycle using MPN and colorimetric methods, respectively. Data obtained were analyzed in relation to drainage frequency, rice growth stage, and rice yield using the Student t test and XLSTAT 7.5.2 statistical software. From the results obtained, the subsurface drainage reduced significantly IRB populations (p = 0.024). However, the drainage did not affect significantly ferrous iron concentration in the soil near rice roots (p = 0.708). The concentration of ferrous iron (p < 0.0001) in soil near rice roots and the number of IRB (p < 0.0001) were significantly higher during the rice tillering and maturity stages. Although no significant difference was observed for rice yield among treatments (p = 0.209), the P2 subsurface drainage showed the highest yield and the lowest concentration of ferrous iron in soil near rice roots.展开更多
Rice is one of the staple crops in Burkina Faso. However, the local production covers only 47% of the population demands. One of the main reasons of the poor productivity in Burkina Faso is iron toxicity which is rela...Rice is one of the staple crops in Burkina Faso. However, the local production covers only 47% of the population demands. One of the main reasons of the poor productivity in Burkina Faso is iron toxicity which is related mainly to the activity of Iron Reducing Bacteria in the rice field’s ecosystems. In order to control the harmful effects of Iron Reducing Bacterial populations and to improve rice productivity, a pots experiment was conducted at the experimental site of the University Ouaga I Pr. Joseph KI-ZERBO. An iron toxic soil from Kou Valley (West of Burkina Faso) and two rice varieties, BOUAKE-189 and ROK-5, sensitive and tolerant to iron toxicity, respectively, were used for the experiment. The pots were drained for 14 days (D2) and amended with chemical fertilizers (NPK + Urea and NPK + Urea + Ca + Mg + Zn complexes). Control pots without drainage and fertilization (D0/NF) were prepared similarly. The kinetics of Iron Reducing Bacterial populations and ferrous iron content in soil near rice roots were monitored throughout the cultural cycle using MPN and colorimetric methods, respectively. The total iron content was evaluated in rice plant using a spectrometric method. Data obtained were analyzed in relation to drainage and fertilization mode, rice growth stage and rice yield using the Student’s t-test and XLSTAT 2014 statistical software. The experiment showed that the combined application of subsurface drainage and NPK + Urea + Ca + Mg + Zn fertilization, reduced significantly the number of IRB in the soil near rice roots for both rice varieties (p = 0.050 and p = 0.020) increased the leaf tissue tolerance to excess amounts of Fe, and rice yield.展开更多
Rivers are the primary contributors of iron and other elements to the global oceans.Iron-reducing bacteria play an important biogeochemical role in coupling the iron and carbon redox cycles.However,the extent of chang...Rivers are the primary contributors of iron and other elements to the global oceans.Iron-reducing bacteria play an important biogeochemical role in coupling the iron and carbon redox cycles.However,the extent of changes in community structures and iron-reduction activities of iron-reducing bacteria in riverine and coastal marine sediments remains unclear.This study presents information on the spatial patterns and relative abundance of iron-reducing bacteria in sediments of the Yellow River estuary and the adjacent Bohai Sea.High-throughput sequencing of bacterial 16S rRNA found that the highest relative abundances and diversities were from the estuary(Yellow River-Bohai Sea mixing zone).Pseudomonas,Thiobacillus,Geobacter,Rhodoferax,and Clostridium were the most abundant putative iron-reducing bacteria genera in the sediments of the Yellow River.Vibrio,Shewanella,and Thiobacillus were the most abundant in the sediments of the Bohai Sea.The putative iron-reducing bacterial community was positively correlated with the concentrations of total nitrogen and ammonium in coastal marine sediments,and was significantly correlated with the concentration of nitrate in river sediments.The riverine sediments,with a more diverse iron-reducing bacterial community,exhibited increased activity of Fe(III)reduction in enrichment cultures.The estuary-wide high abundance of putative iron-reducing bacteria suggests that the effect of river-sea interaction on bacterial distribution patterns is high.The results of this study will help the understanding of the biogeochemical cycling of iron in riverine and coastal marine environments.展开更多
BACKGROUND: Sepsis is a life-threatening inflammatory condition in which the invading pathogen avoids the host's defense mechanisms and continuously stimulates and damages host cells. Consequently, many immune res...BACKGROUND: Sepsis is a life-threatening inflammatory condition in which the invading pathogen avoids the host's defense mechanisms and continuously stimulates and damages host cells. Consequently, many immune responses initially triggered for protection become harmful because of the failure to restore homeostasis, resulting in ongoing hyperinflammation and immunosuppression. METHODS: A literature review was conducted to address bacterial sepsis, describe advances in understanding complex immunological reactions, critically assess diagnostic approaches, and emphasize the importance of studying bacterial bottlenecks in the detection and treatment of sepsis.RESULTS: Diagnosing sepsis via a single laboratory test is not feasible;therefore, multiple key biomarkers are typically monitored, with a focus on trends rather than absolute values. The immediate interpretation of sepsis-associated clinical signs and symptoms, along with the use of specific and sensitive laboratory tests, is crucial for the survival of patients in the early stages. However, long-term mortality associated with sepsis is now recognized, and alongside the progression of this condition, there is an in vivo selection of adapted pathogens.CONCLUSION: Bacterial sepsis remains a significant cause of mortality across all ages and societies. While substantial progress has been made in understanding the immunological mechanisms underlying the inflammatory response, there is growing recognition that the ongoing host-pathogen interactions, including the emergence of adapted virulent strains, shape both the acute and long-term outcomes in sepsis. This underscores the urgent need for novel high-throughput diagnostic methods and a shift toward more pre-emptive, rather than reactive, treatment strategies in sepsis care.展开更多
In this study,two wheat-derived cadmium(Cd)-immobilizing endophytic Pseudomonas paralactis M14 and Priestia megaterium R27 were evaluated for their effects on wheat tissue Cd uptake under hydroponic conditions.Then,th...In this study,two wheat-derived cadmium(Cd)-immobilizing endophytic Pseudomonas paralactis M14 and Priestia megaterium R27 were evaluated for their effects on wheat tissue Cd uptake under hydroponic conditions.Then,the impacts of the biochar(BC),M14+R27(MR),and BC+MR treatments on wheat Cd uptake and the mechanisms involved were investigated at the jointing,heading,and mature stages of wheat plants under field-plot conditions.A hydroponic experiment showed that the MR treatment significantly decreased the above-ground tissue Cd content compared with theM14 or R27 treatment.The BC+MRtreatment reduced the grain Cd content by 51.5%-67.7%and Cd translocation factor at the mature stage of wheat plants and increased the organic matter-bound Cd content by 31%-75%in the rhizosphere soils compared with the BC or MR treatment.Compared with the BC or MR treatment,the relative abundances of the biomarkers associated with Gemmatimonas,Altererythrobacter,Gammaproteobacteria,Xanthomonadaceae,Phenylobacterium,and Nocardioides in the BC+MR-treated rhizosphere microbiome decreased and negatively correlated with the organic matter-bound Cd contents.In the BC+MR-treated root interior microbiome,the relative abundance of the biomarker belonging to Exiguobacterium increased and negatively correlated with the Cd translocation factor,while the relative abundance of the biomarker belonging to Pseudonocardiaceae decreased and positively correlated with the Cd translocation factor.Our findings suggested that the BC+MR treatment reduced Cd availability and Cd transfer through affecting the abundances of these specific biomarkers in the rhizosphere soil and root interior microbiomes,leading to decreased wheat grain Cd uptake in the contaminated soil.展开更多
Diel investigations of water environments are one means to holistically understand the dynamics and functional roles of phytoplankton,bacteria and viruses in these ecosystems.They have the potential to substantially i...Diel investigations of water environments are one means to holistically understand the dynamics and functional roles of phytoplankton,bacteria and viruses in these ecosystems.They have the potential to substantially impact carbon(C),nitrogen(N)and phosphorus(P)biogeochemistry through their respective roles.This study characterizes the phytoplankton,bacteria and virus communities and the elemental composition of various C,N and P nutrients flow over three diel cycles in tropical urban lake.Our results show that ratios of C:N:P fluctuated strongly from the lack of dissolved organic phosphorus(DOP)and PO_(4).Specifically,green algae peaked during day time and exudate dissolved organic matter(DOM)that strongly modulate dissolved organic carbon(DOC):DOP ratio to diel DOP limitation.Multiple linear regression and Stella modelling emphasize the roles of viruses together with Synechococcus as important nutrient recyclers of NH_(4)and PO_(4)in nutrients-limited waters.Respective normalised surface PO_(4)and combined surface and bottom NH_(4)concentration selected both viruses and Synechococcus as important drivers.Process model of N and P biogeochemical cycles can achieve 69%and 57%similar to observed concentration of NH_(4)and PO_(4),respectively.A short latent period of 9 hr was calculated,in addition to the calibrated high infectivity of viruses to Synechococcus.Taken together,the rapid turn-over between Synechococcus and viruses has biogeochemical significance,where the rapid recycling of essential nutrients allows for shortcuts in the N and P cycle,supporting a wide range of microbes.展开更多
Because of the recent widespread usage of antibiotics,the acquisition and dissemination of antibiotic-resistance genes(ARGs)were prevalent in the majority of habitats.Generally,the biological wastewater treatment proc...Because of the recent widespread usage of antibiotics,the acquisition and dissemination of antibiotic-resistance genes(ARGs)were prevalent in the majority of habitats.Generally,the biological wastewater treatment processes used in wastewater treatment plants have a limited efficiencies of antibiotics resistant bacteria(ARB)disinfection and ARGs degradation and even promote the proliferation of ARGs.Problematically,ARB and ARGs in effluent pose potential risks if they are not further treated.Photocatalytic oxidation is considered a promising disinfection technology,where the photocatalytic process generates many free radicals that enhance the interaction between light and deoxyribonucleic acid(DNA)for ARB elimination and subsequent degradation of ARGs.This reviewaims to illustrate the progress of photocatalytic oxidation technology for removing antibiotics resistant(AR)from wastewater in recent years.We discuss the sources and transfer of ARGs in wastewater.The overall removal efficiencies of ultraviolet radiation(UV)/chlorination,UV/ozone,UV/H_(2)O_(2),and UV/sulfate-radical based system for ARB and ARGs,as well as the experimental parameters and removal mechanisms,are systematically discussed.The contribution of photocatalytic materials based on TiO_(2) and g-C_(3)N_(4) to the inactivation of ARB and degradation of ARGs is highlighted,producingmany free radicals to attack ARB and ARGs while effectively limiting the horizontal gene transfer(HGT)in wastewater.Finally,based on the reviewed studies,future research directions are proposed to realize specific photocatalytic oxidation technology applications and overcome current challenges.展开更多
Rice-fish coculture(RFC)has aroused extensive concern for its contribution to food security and resource conservation,but whether it can improve soil phosphorus(P)availability and affect microbe-mediated P turnover re...Rice-fish coculture(RFC)has aroused extensive concern for its contribution to food security and resource conservation,but whether it can improve soil phosphorus(P)availability and affect microbe-mediated P turnover remains elusive.Herein,we conducted a microcosm experiment to assess the impacts of RFC combined with(50 mg P kg^(-1)as KH2PO4)and without inorganic P addition on P fractions,P availability,and phoD-harboring bacterial community composition.The results revealed that RFC without P addition significantly improved P availability and phosphatase activity in paddy soil,while soil available P(AP),pH,and microbial biomass P(MBP)contributed to regulating P fractions.Moreover,the phoD-harboring bacterial abundance was linked to phosphatase activity,AP,total carbon(TC),and total P(TP)contents,and the ratios of TC to total nitrogen(TN)and TN to TP.We also found that the keystone taxa of phoD-harboring bacteria contributed to phosphatase production as well as organic P mineralization,thereby improving P availability.Our findings suggest that RFC without P addition is beneficial for promoting the expression of phoD-harboring bacterial functions to improve the capacity of P mineralization.Overall,our study provides insights into the responses of phoD-harboring bacterial functions for P turnover to RFC combined with and without P addition,showing the potential utilization of P resources in agricultural soil and the contribution of phosphatase activity to P acquisition in agriculture ecosystem.展开更多
Plate culture counting and strain isolation methods were utilized to assess the species richness and abundance of planktonic and attached bacteria on glass plates in the surface and bottom seawater of Qingdao Middle H...Plate culture counting and strain isolation methods were utilized to assess the species richness and abundance of planktonic and attached bacteria on glass plates in the surface and bottom seawater of Qingdao Middle Harbor over a year,with monthly and quarterly sampling.Both species richness and bacterial numbers exhibited seasonal variations.Specifically,the abundance of attached bacteria and bacterioplankton peaked in June and July,corresponding to higher water temperatures in summer and autumn,while lower abundances were noted in January and December during cooler periods.Throughout the year,the species richness of attached bacteria consistently exceeded that of planktonic bacteria in both shallow and deep waters.Pseudoalteromonas emerged as the most prevalent genus among both planktonic and attached bacteria in surface and bottom seawater samples.Furthermore,the magnitude of changes in species richness and abundance for attached bacteria(0.66×10^(5)-15.85×10^(5)CFU/cm^(2))was greater than that observed for planktonic bacteria(0.58×10^(8)-5.33×10^(8)CFU/L).We propose that the attached bacterial populations,situated in limited microenvironments within the larger seawater ecosystem,exhibit heightened sensitivity to environmental fluctuations,resulting in more rapid shifts in population dynamics and lower ecological stability.The theoretical implications and potential applications of these findings warrant further investigation.展开更多
Salt-tolerant bacteria associated with halophytes enhance plant resistance and adaptation to environmental stress.The purpose of this study was to investigate the diversity and plant-beneficial traits of bacteria asso...Salt-tolerant bacteria associated with halophytes enhance plant resistance and adaptation to environmental stress.The purpose of this study was to investigate the diversity and plant-beneficial traits of bacteria associated with three halophytes in an arid land,Northwest China.The bacterial strains were isolated from the roots,shoots,rhizosphere,and bulk soil of three halophytes,i.e.,Salicornia europaea L.,Kalidium foliatum(Pall.)Moq.,and Suaeda aralocaspica(Bunge)Freitag&Schütze,collected from the saline soils near to the Wujiaqu City,Xinjiang,Northwest China.A total of 567 strains were isolated and identified from these three halophytes belonging to 4 phyla,6 classes,25 orders,36 families,and 66 genera,including 147 potential novel species.A total of 213 strains exhibited one or more plant growthpromoting properties,while 20 strains demonstrated multiple in vitro plant growth-promoting activities,including phosphate solubilization,nitrogen fixation,siderophore production,and production of hydrolytic enzymes such as protease and cellulase.Our findings showed that halophytes in the arid land harbor diverse bacteria with the potential to enhance plant growth and adaptability under challenging environmental conditions.展开更多
Objective: This study assessed the effects of consuming acetic acid bacteria (Gluconacetobacter hansenii GK-1) for 12 weeks on fatigue induced by temporary mental stress. Methods: This randomized, double-blind, placeb...Objective: This study assessed the effects of consuming acetic acid bacteria (Gluconacetobacter hansenii GK-1) for 12 weeks on fatigue induced by temporary mental stress. Methods: This randomized, double-blind, placebo-controlled, parallel-group study included 100 healthy male and female adults aged 20 - 64 years. Participants consumed either the G. hansenii GK-1 supplement (9 × 10⁹ cells/day) or a placebo daily for 12 weeks. The impact of temporary mental stress on fatigue in G. hansenii GK-1 was assessed using a Visual Analog Scale (VAS) before the study began and after 12 weeks of supplementation. Results: Subjective fatigue measured by Visual Analog Scale (VAS) showed a significant decrease in fatigue induced by temporary mental stress after 12 weeks of consumption in the G. hansenii GK-1 group compared with the placebo group. No adverse events were attributed to G. hansenii GK-1. These findings confirm that continuous oral ingestion of G. hansenii GK-1 by healthy Japanese adults reduces feelings of fatigue caused by temporary mental stress.展开更多
Both the broad-spectrum bactericidal properties of disinfectants and the inhibitory effects of antibiotics pose potential threats to the activity,functionality,and probiotic properties of Lactid acid bacteria(LAB).The...Both the broad-spectrum bactericidal properties of disinfectants and the inhibitory effects of antibiotics pose potential threats to the activity,functionality,and probiotic properties of Lactid acid bacteria(LAB).Therefore,it is essential to systematically evaluate the tolerance of lactic acid bacteria to common disinfectants and antibiotics.This study assessed 60 LAB strains isolated from the fermented foods for their tolerance to seven disinfectants and nine antibiotics.The results indicated that,compared to pathogenic bacteria,most LAB exhibited stronger tolerance to disinfectants.Sub-inhibitory concentrations of disinfectants inhibited biofilm formation in most LAB,while sub-inhibitory concentrations of glutaraldehyde tended to promote biofilm formation.This suggests that commonly used disinfectants can eliminate pathogenic bacteria without killing LAB,providing guidance for disinfectant use.LAB were highly sensitive to ampicillin and chloramphenicol,while showing some tolerance to norfloxacin,polymyxin,and sulfamethoxazole.This indicates LAB have a notable antibiotic resistance profile,which includes both natural resistance characteristics and instances of acquired resistance,along with multiple drug resistance and cross-resistance between antibiotics and disinfectants.This study provides an important guidance for disinfection practices in industrial utilizing LAB,such as food and biomedicine,and offers a reference for the use of antibiotics.展开更多
The Makran Sea is a complex marine environment.The purpose of this research is screening of emulsifier-producing bacteria in this marine environment and optimization of emulsifier production by the best-producing stra...The Makran Sea is a complex marine environment.The purpose of this research is screening of emulsifier-producing bacteria in this marine environment and optimization of emulsifier production by the best-producing strain.Marine samples(seawater and sediments)were collected from four different zones in the Makran Sea.The emulsification activity index(E_(24))and Bacterial Ad-hesion To Hydrocarbons(BATH)were used to select the best emulsifier-producing strains.The prevalent strains were identified by PCR.The optimization of the emulsifier production medium by the best strain was done by two-level factorial design.Seventeen emulsifier-producing strains were isolated from sediments and seawater in the Makran Sea.The strains M6,BS-2,and J6 were select-ed between all isolates because they have 83%,91%,and 85%emulsification activity(E_(24))respectively.The results of sequencing confirmed that these three strains(M6,BS-2,and J6)belong to Cobetia marina,Shewanella alga,and Thalassospira permensis re-spectively.Maximum emulsifier production occurred at crude oil concentration(4%,v/v),peptone(2.5 g/L),yeast extract(1.5 g/L),molasses(2%),and at a temperature of 25℃.The results of this research confirmed that the Makran Sea has the potential to reach ro-bust marine bacteria with different biotechnological applications.展开更多
This study examined the effects of pasteurization(PAS),ultrasonic sterilization(ULS),and microwave sterilization(MWS)on the quality and storage characteristics of brine-fermented tofu(BFT)and fermented tofu(FT).Compar...This study examined the effects of pasteurization(PAS),ultrasonic sterilization(ULS),and microwave sterilization(MWS)on the quality and storage characteristics of brine-fermented tofu(BFT)and fermented tofu(FT).Comparative analysis revealed that MWS had a negligible detrimental effect on the structural integrity and organoleptic properties of BFT and FT,while effectively maintaining its water-holding capacity(WHC)and exhibiting the least impact on its texture.In contrast,PAS and ULS increased hardness and chewiness significantly(P<0.05),but ULS also enhanced the brightness of tofu.Throughout the storage period,the WHC,elasticity,and sensory properties of tofu generally decreased,whereas the hardness and chewiness increased.PAS-BFT and MWS-FT maintained sensory quality for the longest periods of 14 and 12 days respectively,and could be decomposed to more small molecule peptides within 0–8 days and 0–6 days,which are more easily to be absorbed by the body.The findings discovered that MWS is the most suitable method for sterilization of tofu,with superior capability in maintaining the quality,extending shelf life,and improving digestibility of tofu.展开更多
Deep learning neural network incorporating surface enhancement Raman scattering technique(SERS)is becoming as a powerful tool for the precise classifications and diagnosis of bacterial infections.However,the large amo...Deep learning neural network incorporating surface enhancement Raman scattering technique(SERS)is becoming as a powerful tool for the precise classifications and diagnosis of bacterial infections.However,the large amount of sample requirement and time-consuming sample collection severely hinder its applications.We herein propose a spectral concatenation strategy for residual neural network using nonspecific and specific SERS spectra for the training data augmentation,which is accessible to acquiring larger training dataset with same number of SERS spectra or same size of training dataset with fewer SERS spectra,compared with pure non-specific SERS spectra.With this strategy,the training loss exhibit rapid convergence,and an average accuracy up to 100%in bacteria classifications was achieved with50 SERS spectra for each kind of bacterium;even reduced to 20 SERS spectra per kind of bacterium,classification accuracy is still>95%,demonstrating marked advantage over the results without spectra concatenation.This method can markedly improve the classification accuracy under fewer samples and reduce the data collection workload,and can evidently enhance the performance when used in different machine learning models with high generalization ability.Therefore,this strategy is beneficial for rapid and accurate bacteria classifications with residual neural network.展开更多
Mariculture tailwater poses significant environmental challenges such as water pollution and eutrophication.Photosynthetic bacteria(PSB)have been widely used for pollutant treatment.The integrated aquaculture wastewat...Mariculture tailwater poses significant environmental challenges such as water pollution and eutrophication.Photosynthetic bacteria(PSB)have been widely used for pollutant treatment.The integrated aquaculture wastewater bioremediation system(IAWBS)consists of four key components:sedimentation,biofilm,shellfish,and macro-algae.However,there is still some room for improvement in the treatment efficiency of the IAWBS.In this study,PSB(Rhodopseudomonos,Rhodobacteria,Rhodococcus)were added to the system.High-throughput amplicon of 16S rRNA,PERMANOVA,NMDS and other statistical analyses were used to investigate the impacts of PSB.The results showed that significant removal efficiencies of CODMn,NH_(4)^(+)-N,NO_(3)^(-)-N,NO_(2)^(-)-N,PO_(4)^(3-)-P were 71.42%,91.37%,91.72%,87.20%,and 88.80%,respectively.The impact of PSB on bacterioplankton community(BC)was not affected by the time interval but affected by different units,Proteobacteria,Bacteriodia and Actinobacteria were the most abundant phyla in all the units.Alpha diversity underscored a significant decrease in bacterial community diversity due to the PSB.Notably,the PERMANOVA analysis highlighted a significant interaction between the time interval and treated unit,influencing the composition of the microbial community(R^(2)=0.152;P=0.001).This study provides a better understanding of the role of photosynthetic bacteria in an integrated bioremediation system that can effectively treat mariculture tailwater,which is of great significance for the sustainable development of aquaculture.展开更多
Bioremediation is an efficient and popular approach for domestic wastewater treatment while the pollutant discharge standards are difficult to achieve under low-temperature conditions. The application of cold-resistan...Bioremediation is an efficient and popular approach for domestic wastewater treatment while the pollutant discharge standards are difficult to achieve under low-temperature conditions. The application of cold-resistant bacteria has gained increasing attention, but direct introduction to sewage leads to poor environmental adaptability and low microbial activity. Biochar was used as a carrier to immobilize the bacteria to improve microbial survival and activity in this study. The basic physicochemical properties of bacteria immobilized by biochar and ammonium nitrogen removal efficiency were analyzed. The process mechanism of ammonium nitrogen removal was further explored using kinetic fitting and molecular simulation calculations. The results showed that biochar immobilization of cold-resistant bacteria achieved a significantly higher ammonium nitrogen removal rate of 0.88 mg/(L·h) compared to free mixed bacteria(0.74 mg/(L·h)) and biochar alone(0.22 mg/(L·h)). It also exhibited a removal efficiency of 96.56%, which was 15.02% and 72.58% higher than that of free mixed bacteria and biochar, respectively. Adsorption kinetics further revealed that the pseudosecond-order kinetic equation was a better fit for characterizing ammonia-nitrogen removal by biocharimmobilized cold-resistant bacteria. Combining microscopic morphology analysis and molecular simulations demonstrated that enriching functional groups on biochar enhanced its NH_4~+ adsorption capacity by increasing surface activity and polarity, as well as the biodegradation ability of NH_4~+ by improving the interactions between biochar and active enzymes. These findings provide valuable insights into developing more effective ways to improve wastewater treatment efficiency under low temperatures.展开更多
Hyperuricemia(HUA)is characterized by elevated levels of uric acid(UA)in the bloodstream,resulting from either excessive production or insufficient excretion of UA within the body.If left untreated,progressive or pers...Hyperuricemia(HUA)is characterized by elevated levels of uric acid(UA)in the bloodstream,resulting from either excessive production or insufficient excretion of UA within the body.If left untreated,progressive or persistent HUA can lead to gout,causing significant harm to human health.Lactic acid bacteria(LAB),generally recognized as safe(GRAS)probiotics,have been shown to alleviate symptoms associated with gastrointestinal disorders such as irritable bowel syndrome and inflammatory bowel disease while supporting overall bodily functions and health.Recently,LAB has emerged as a potentially safe,cost-effective and efficient treatment for HUA.This comprehensive review aims to explore the current literature on the mechanisms through which LAB controls HUA.These mechanisms include suppressing purine metabolism,absorbing purine compounds,modulating microbiota to maintain host global purine homeostasis,reducing intestinal permeability,producing metabolites that alleviate HUA symptoms,promoting the expression of urate excretory proteins and inhibiting the expression of urate reabsorption proteins.The findings presented in this review provide a framework for further investigation into how probiotic LAB can alleviate HUA by influencing UA metabolism and elucidating their underlying action mechanisms.展开更多
基金Project(51708561)supported by the National Natural Science Foundation of ChinaProjects(CZP17097,CZW15037)supported by the Fundamental Research Funds for the Central Universities,China
文摘Ethylthionocarbamates (ETC), which is the most widely used as collectors in the flotation of sulfide, is known to cause serious pollution to soil and groundwater. The potential biodegradation of ETC was evaluated by applying a mixed culture of iron-reducing bacteria (IRB) enriched from tailings dam sediments. The results showed that ETC can be degraded by IRB coupled to Fe(III) reduction, both of which can be increased in the presence of anthraquinone-2,6-disulfonate (AQDS). Moreover, Fe(III)-EDTA was found to be a more favorable terminal electron acceptor compared to α-Fe2O3, e.g., within 30 d, 72% of ETC was degraded when α-Fe2O3+AQDS was applied, while it is 82.67% when Fe(III)-EDTA+AQDS is added. The dynamic models indicated that the kETC degradation was decreased in the order of Fe(III)-EDTA+AQDS〉α-Fe2O3+AQDS〉Fe(III)-EDTA〉α-Fe2O3, with the corresponding maximum biodegradation rates being 2.6, 2.45, 2.4 and 2.0 mg/(L·d), respectively, and positive parallel correlations could be observed between kFe(III) and kETC. These findings demonstrate that IRB has a good application prospect in flotation wastewater.
文摘Iron toxicity is a major stress to rice caused by a high concentration of reduced iron, in the soil in many lowlands worldwide. To reduce iron toxicity in the West African lowlands, an investigation was performed at the site of the University of Ouagadougou, in pots containing an iron toxic soil from the Kou Valley (West of Burkina Faso). The experiment objective was to study the effect of mineral fertilizer on Iron Reducing Bacteria (IRB) dynamics and activity during rice cultivation, iron accumulation in rice plant and rice biomass yield under iron toxicity conditions. BOUAKE-189 and ROK-5 rice varieties, sensitive and tolerant to iron toxicity, respectively, were used for the experiment. The pots were amended with chemical fertilizers (NPK + Urea and NPK + Urea + Ca + Mg + Zn complex). Control pots without fertilization were prepared similarly. The kinetics of IRB and ferrous iron content in soil near rice roots were monitored throughout the cultural cycle using MPN and colorimetric methods, respectively. The total iron content was evaluated in rice plant using spectrometric method. Data obtained were analyzed in relation to fertilization mode, rice growth stage and rice yield using the student’s t-test and XLSTAT 2014 statistical software. The experiment revealed that NPK + Urea and NPK + Urea + Ca + Mg + Zn fertilization, decreased significantly (p < 0.0001) the number of IRB in the soil for BOUAKE-189 rice varieties. In most pots, highest IRB densities and ferrous iron content in soil were recorded from rice tillering and flowering to maturity stages, indicating that rice plants promoted microbial processes and iron reduction in soil. From the study, the NPK + Urea amendment decreased significantly ferrous iron content (p < 0.0001) in soil near BOUAKE-189 and ROK-5 rice varieties roots relatively to control pots. However, NPK + Urea + Ca + Zn + Mg amendment increased significantly ferrous iron content (p < 0.0001) in the soil near roots, Fe accumulation in plant biomass and rice yield for the two rice varieties.
文摘Iron toxicity is one of the main edaphic constraints that hamper rice production in West African savanna and forest lowlands. Although chemical reduction processes of various types of pedogenic iron oxides could not be underestimated, the bulk of these processes can be ascribed to the specific activity of Iron-Reducing Bacteria (IRB). The reducing conditions of waterlogged lowland soils boost iron toxicity through the reduction of almost all iron into ferrous form (Fe2+), which can cause disorder in rice plant and crop yield losses. Aiming to contribute at the improvement of rice yield in Africa, an experiment was developed to evaluate the impact of subsurface drainage on IRB dynamics and activity during rice cultivation. Twelve concrete microplots with a clay-loam soil and a rice variety susceptible to iron toxicity (FKR 19) were used for the experiment. Soil in microplots was drained for 7 days (P1), 14 days (P2), and 21 days (P3), respectively. Control (T) microplots without drainage were prepared similarly. The evolution of IRB populations and the content of ferrous iron in the paddy soil and in soil near rice root were monitored throughout the cultural cycle using MPN and colorimetric methods, respectively. Data obtained were analyzed in relation to drainage frequency, rice growth stage, and rice yield using the Student t test and XLSTAT 7.5.2 statistical software. From the results obtained, the subsurface drainage reduced significantly IRB populations (p = 0.024). However, the drainage did not affect significantly ferrous iron concentration in the soil near rice roots (p = 0.708). The concentration of ferrous iron (p < 0.0001) in soil near rice roots and the number of IRB (p < 0.0001) were significantly higher during the rice tillering and maturity stages. Although no significant difference was observed for rice yield among treatments (p = 0.209), the P2 subsurface drainage showed the highest yield and the lowest concentration of ferrous iron in soil near rice roots.
文摘Rice is one of the staple crops in Burkina Faso. However, the local production covers only 47% of the population demands. One of the main reasons of the poor productivity in Burkina Faso is iron toxicity which is related mainly to the activity of Iron Reducing Bacteria in the rice field’s ecosystems. In order to control the harmful effects of Iron Reducing Bacterial populations and to improve rice productivity, a pots experiment was conducted at the experimental site of the University Ouaga I Pr. Joseph KI-ZERBO. An iron toxic soil from Kou Valley (West of Burkina Faso) and two rice varieties, BOUAKE-189 and ROK-5, sensitive and tolerant to iron toxicity, respectively, were used for the experiment. The pots were drained for 14 days (D2) and amended with chemical fertilizers (NPK + Urea and NPK + Urea + Ca + Mg + Zn complexes). Control pots without drainage and fertilization (D0/NF) were prepared similarly. The kinetics of Iron Reducing Bacterial populations and ferrous iron content in soil near rice roots were monitored throughout the cultural cycle using MPN and colorimetric methods, respectively. The total iron content was evaluated in rice plant using a spectrometric method. Data obtained were analyzed in relation to drainage and fertilization mode, rice growth stage and rice yield using the Student’s t-test and XLSTAT 2014 statistical software. The experiment showed that the combined application of subsurface drainage and NPK + Urea + Ca + Mg + Zn fertilization, reduced significantly the number of IRB in the soil near rice roots for both rice varieties (p = 0.050 and p = 0.020) increased the leaf tissue tolerance to excess amounts of Fe, and rice yield.
基金the National Natural Science Foundation of China(nos.91751112.41807325,and 41573071)the senior user project of RV KEXUE(no.KEXUE2018G01)+2 种基金the Key Research Project of Frontier Science(no.QYZDJ-SSW-DQC015)of Chinese Academy of Sciencesthe Natural Science Foundation(no.JQ201608 and ZR2O18MDOI1)the Young Taishan Scholars Program(no.tsqn20161054)of Shandong Province.
文摘Rivers are the primary contributors of iron and other elements to the global oceans.Iron-reducing bacteria play an important biogeochemical role in coupling the iron and carbon redox cycles.However,the extent of changes in community structures and iron-reduction activities of iron-reducing bacteria in riverine and coastal marine sediments remains unclear.This study presents information on the spatial patterns and relative abundance of iron-reducing bacteria in sediments of the Yellow River estuary and the adjacent Bohai Sea.High-throughput sequencing of bacterial 16S rRNA found that the highest relative abundances and diversities were from the estuary(Yellow River-Bohai Sea mixing zone).Pseudomonas,Thiobacillus,Geobacter,Rhodoferax,and Clostridium were the most abundant putative iron-reducing bacteria genera in the sediments of the Yellow River.Vibrio,Shewanella,and Thiobacillus were the most abundant in the sediments of the Bohai Sea.The putative iron-reducing bacterial community was positively correlated with the concentrations of total nitrogen and ammonium in coastal marine sediments,and was significantly correlated with the concentration of nitrate in river sediments.The riverine sediments,with a more diverse iron-reducing bacterial community,exhibited increased activity of Fe(III)reduction in enrichment cultures.The estuary-wide high abundance of putative iron-reducing bacteria suggests that the effect of river-sea interaction on bacterial distribution patterns is high.The results of this study will help the understanding of the biogeochemical cycling of iron in riverine and coastal marine environments.
基金funded by the Deanship of Scientific Research (DSR) at King Abdulaziz UniversityJeddah+1 种基金Saudi Arabiaunder grant number G-150-248-1443。
文摘BACKGROUND: Sepsis is a life-threatening inflammatory condition in which the invading pathogen avoids the host's defense mechanisms and continuously stimulates and damages host cells. Consequently, many immune responses initially triggered for protection become harmful because of the failure to restore homeostasis, resulting in ongoing hyperinflammation and immunosuppression. METHODS: A literature review was conducted to address bacterial sepsis, describe advances in understanding complex immunological reactions, critically assess diagnostic approaches, and emphasize the importance of studying bacterial bottlenecks in the detection and treatment of sepsis.RESULTS: Diagnosing sepsis via a single laboratory test is not feasible;therefore, multiple key biomarkers are typically monitored, with a focus on trends rather than absolute values. The immediate interpretation of sepsis-associated clinical signs and symptoms, along with the use of specific and sensitive laboratory tests, is crucial for the survival of patients in the early stages. However, long-term mortality associated with sepsis is now recognized, and alongside the progression of this condition, there is an in vivo selection of adapted pathogens.CONCLUSION: Bacterial sepsis remains a significant cause of mortality across all ages and societies. While substantial progress has been made in understanding the immunological mechanisms underlying the inflammatory response, there is growing recognition that the ongoing host-pathogen interactions, including the emergence of adapted virulent strains, shape both the acute and long-term outcomes in sepsis. This underscores the urgent need for novel high-throughput diagnostic methods and a shift toward more pre-emptive, rather than reactive, treatment strategies in sepsis care.
基金supported by the National Natural Science Foundation of China(No.41977199).
文摘In this study,two wheat-derived cadmium(Cd)-immobilizing endophytic Pseudomonas paralactis M14 and Priestia megaterium R27 were evaluated for their effects on wheat tissue Cd uptake under hydroponic conditions.Then,the impacts of the biochar(BC),M14+R27(MR),and BC+MR treatments on wheat Cd uptake and the mechanisms involved were investigated at the jointing,heading,and mature stages of wheat plants under field-plot conditions.A hydroponic experiment showed that the MR treatment significantly decreased the above-ground tissue Cd content compared with theM14 or R27 treatment.The BC+MRtreatment reduced the grain Cd content by 51.5%-67.7%and Cd translocation factor at the mature stage of wheat plants and increased the organic matter-bound Cd content by 31%-75%in the rhizosphere soils compared with the BC or MR treatment.Compared with the BC or MR treatment,the relative abundances of the biomarkers associated with Gemmatimonas,Altererythrobacter,Gammaproteobacteria,Xanthomonadaceae,Phenylobacterium,and Nocardioides in the BC+MR-treated rhizosphere microbiome decreased and negatively correlated with the organic matter-bound Cd contents.In the BC+MR-treated root interior microbiome,the relative abundance of the biomarker belonging to Exiguobacterium increased and negatively correlated with the Cd translocation factor,while the relative abundance of the biomarker belonging to Pseudonocardiaceae decreased and positively correlated with the Cd translocation factor.Our findings suggested that the BC+MR treatment reduced Cd availability and Cd transfer through affecting the abundances of these specific biomarkers in the rhizosphere soil and root interior microbiomes,leading to decreased wheat grain Cd uptake in the contaminated soil.
文摘Diel investigations of water environments are one means to holistically understand the dynamics and functional roles of phytoplankton,bacteria and viruses in these ecosystems.They have the potential to substantially impact carbon(C),nitrogen(N)and phosphorus(P)biogeochemistry through their respective roles.This study characterizes the phytoplankton,bacteria and virus communities and the elemental composition of various C,N and P nutrients flow over three diel cycles in tropical urban lake.Our results show that ratios of C:N:P fluctuated strongly from the lack of dissolved organic phosphorus(DOP)and PO_(4).Specifically,green algae peaked during day time and exudate dissolved organic matter(DOM)that strongly modulate dissolved organic carbon(DOC):DOP ratio to diel DOP limitation.Multiple linear regression and Stella modelling emphasize the roles of viruses together with Synechococcus as important nutrient recyclers of NH_(4)and PO_(4)in nutrients-limited waters.Respective normalised surface PO_(4)and combined surface and bottom NH_(4)concentration selected both viruses and Synechococcus as important drivers.Process model of N and P biogeochemical cycles can achieve 69%and 57%similar to observed concentration of NH_(4)and PO_(4),respectively.A short latent period of 9 hr was calculated,in addition to the calibrated high infectivity of viruses to Synechococcus.Taken together,the rapid turn-over between Synechococcus and viruses has biogeochemical significance,where the rapid recycling of essential nutrients allows for shortcuts in the N and P cycle,supporting a wide range of microbes.
基金supported by the National Natural Science Foundation of China (Nos.52100182 and 52300204)the the Science and Technology Innovation Program of Hunan Province (No.2023RC3122).
文摘Because of the recent widespread usage of antibiotics,the acquisition and dissemination of antibiotic-resistance genes(ARGs)were prevalent in the majority of habitats.Generally,the biological wastewater treatment processes used in wastewater treatment plants have a limited efficiencies of antibiotics resistant bacteria(ARB)disinfection and ARGs degradation and even promote the proliferation of ARGs.Problematically,ARB and ARGs in effluent pose potential risks if they are not further treated.Photocatalytic oxidation is considered a promising disinfection technology,where the photocatalytic process generates many free radicals that enhance the interaction between light and deoxyribonucleic acid(DNA)for ARB elimination and subsequent degradation of ARGs.This reviewaims to illustrate the progress of photocatalytic oxidation technology for removing antibiotics resistant(AR)from wastewater in recent years.We discuss the sources and transfer of ARGs in wastewater.The overall removal efficiencies of ultraviolet radiation(UV)/chlorination,UV/ozone,UV/H_(2)O_(2),and UV/sulfate-radical based system for ARB and ARGs,as well as the experimental parameters and removal mechanisms,are systematically discussed.The contribution of photocatalytic materials based on TiO_(2) and g-C_(3)N_(4) to the inactivation of ARB and degradation of ARGs is highlighted,producingmany free radicals to attack ARB and ARGs while effectively limiting the horizontal gene transfer(HGT)in wastewater.Finally,based on the reviewed studies,future research directions are proposed to realize specific photocatalytic oxidation technology applications and overcome current challenges.
基金supported by the Key-Area Research and Development Program of Guangdong Province,China(No.2021B0202030002)the Science and Technology Planning Project of Guangdong Province,China(No.2019B030301007)+2 种基金the Guangdong Provincial Special Project of Rural Revitalization Strategy,China(No.(2021)12)the Joint Team Project of Guangdong Laboratory for Lingnan Modern Agriculture,China(No.NT2021010)the Innovation Team Construction Project of Modern Agricultural Industry Technology Systems of Guangdong Province,China(No.2022KJ105).
文摘Rice-fish coculture(RFC)has aroused extensive concern for its contribution to food security and resource conservation,but whether it can improve soil phosphorus(P)availability and affect microbe-mediated P turnover remains elusive.Herein,we conducted a microcosm experiment to assess the impacts of RFC combined with(50 mg P kg^(-1)as KH2PO4)and without inorganic P addition on P fractions,P availability,and phoD-harboring bacterial community composition.The results revealed that RFC without P addition significantly improved P availability and phosphatase activity in paddy soil,while soil available P(AP),pH,and microbial biomass P(MBP)contributed to regulating P fractions.Moreover,the phoD-harboring bacterial abundance was linked to phosphatase activity,AP,total carbon(TC),and total P(TP)contents,and the ratios of TC to total nitrogen(TN)and TN to TP.We also found that the keystone taxa of phoD-harboring bacteria contributed to phosphatase production as well as organic P mineralization,thereby improving P availability.Our findings suggest that RFC without P addition is beneficial for promoting the expression of phoD-harboring bacterial functions to improve the capacity of P mineralization.Overall,our study provides insights into the responses of phoD-harboring bacterial functions for P turnover to RFC combined with and without P addition,showing the potential utilization of P resources in agricultural soil and the contribution of phosphatase activity to P acquisition in agriculture ecosystem.
基金The National Natural Science Foundation of China under contract Nos 42206126 and 42076044the Natural Science Foundation of Shandong Province under contract No.ZR2021QD099.
文摘Plate culture counting and strain isolation methods were utilized to assess the species richness and abundance of planktonic and attached bacteria on glass plates in the surface and bottom seawater of Qingdao Middle Harbor over a year,with monthly and quarterly sampling.Both species richness and bacterial numbers exhibited seasonal variations.Specifically,the abundance of attached bacteria and bacterioplankton peaked in June and July,corresponding to higher water temperatures in summer and autumn,while lower abundances were noted in January and December during cooler periods.Throughout the year,the species richness of attached bacteria consistently exceeded that of planktonic bacteria in both shallow and deep waters.Pseudoalteromonas emerged as the most prevalent genus among both planktonic and attached bacteria in surface and bottom seawater samples.Furthermore,the magnitude of changes in species richness and abundance for attached bacteria(0.66×10^(5)-15.85×10^(5)CFU/cm^(2))was greater than that observed for planktonic bacteria(0.58×10^(8)-5.33×10^(8)CFU/L).We propose that the attached bacterial populations,situated in limited microenvironments within the larger seawater ecosystem,exhibit heightened sensitivity to environmental fluctuations,resulting in more rapid shifts in population dynamics and lower ecological stability.The theoretical implications and potential applications of these findings warrant further investigation.
基金funded by the Key Research and Development Project of Xinjiang Uygur Autonomous Region (2024B02015-3)the Regional Coordinated Innovation Project (Shanghai Cooperation Organization Science and Technology Partnership Program) of Xinjiang Uygur Autonomous Region (2025E01024)
文摘Salt-tolerant bacteria associated with halophytes enhance plant resistance and adaptation to environmental stress.The purpose of this study was to investigate the diversity and plant-beneficial traits of bacteria associated with three halophytes in an arid land,Northwest China.The bacterial strains were isolated from the roots,shoots,rhizosphere,and bulk soil of three halophytes,i.e.,Salicornia europaea L.,Kalidium foliatum(Pall.)Moq.,and Suaeda aralocaspica(Bunge)Freitag&Schütze,collected from the saline soils near to the Wujiaqu City,Xinjiang,Northwest China.A total of 567 strains were isolated and identified from these three halophytes belonging to 4 phyla,6 classes,25 orders,36 families,and 66 genera,including 147 potential novel species.A total of 213 strains exhibited one or more plant growthpromoting properties,while 20 strains demonstrated multiple in vitro plant growth-promoting activities,including phosphate solubilization,nitrogen fixation,siderophore production,and production of hydrolytic enzymes such as protease and cellulase.Our findings showed that halophytes in the arid land harbor diverse bacteria with the potential to enhance plant growth and adaptability under challenging environmental conditions.
文摘Objective: This study assessed the effects of consuming acetic acid bacteria (Gluconacetobacter hansenii GK-1) for 12 weeks on fatigue induced by temporary mental stress. Methods: This randomized, double-blind, placebo-controlled, parallel-group study included 100 healthy male and female adults aged 20 - 64 years. Participants consumed either the G. hansenii GK-1 supplement (9 × 10⁹ cells/day) or a placebo daily for 12 weeks. The impact of temporary mental stress on fatigue in G. hansenii GK-1 was assessed using a Visual Analog Scale (VAS) before the study began and after 12 weeks of supplementation. Results: Subjective fatigue measured by Visual Analog Scale (VAS) showed a significant decrease in fatigue induced by temporary mental stress after 12 weeks of consumption in the G. hansenii GK-1 group compared with the placebo group. No adverse events were attributed to G. hansenii GK-1. These findings confirm that continuous oral ingestion of G. hansenii GK-1 by healthy Japanese adults reduces feelings of fatigue caused by temporary mental stress.
基金supported by the National Science Foundation of China (32001663)。
文摘Both the broad-spectrum bactericidal properties of disinfectants and the inhibitory effects of antibiotics pose potential threats to the activity,functionality,and probiotic properties of Lactid acid bacteria(LAB).Therefore,it is essential to systematically evaluate the tolerance of lactic acid bacteria to common disinfectants and antibiotics.This study assessed 60 LAB strains isolated from the fermented foods for their tolerance to seven disinfectants and nine antibiotics.The results indicated that,compared to pathogenic bacteria,most LAB exhibited stronger tolerance to disinfectants.Sub-inhibitory concentrations of disinfectants inhibited biofilm formation in most LAB,while sub-inhibitory concentrations of glutaraldehyde tended to promote biofilm formation.This suggests that commonly used disinfectants can eliminate pathogenic bacteria without killing LAB,providing guidance for disinfectant use.LAB were highly sensitive to ampicillin and chloramphenicol,while showing some tolerance to norfloxacin,polymyxin,and sulfamethoxazole.This indicates LAB have a notable antibiotic resistance profile,which includes both natural resistance characteristics and instances of acquired resistance,along with multiple drug resistance and cross-resistance between antibiotics and disinfectants.This study provides an important guidance for disinfection practices in industrial utilizing LAB,such as food and biomedicine,and offers a reference for the use of antibiotics.
基金supported by Shahid Bahonar Universi-ty of Kerman.
文摘The Makran Sea is a complex marine environment.The purpose of this research is screening of emulsifier-producing bacteria in this marine environment and optimization of emulsifier production by the best-producing strain.Marine samples(seawater and sediments)were collected from four different zones in the Makran Sea.The emulsification activity index(E_(24))and Bacterial Ad-hesion To Hydrocarbons(BATH)were used to select the best emulsifier-producing strains.The prevalent strains were identified by PCR.The optimization of the emulsifier production medium by the best strain was done by two-level factorial design.Seventeen emulsifier-producing strains were isolated from sediments and seawater in the Makran Sea.The strains M6,BS-2,and J6 were select-ed between all isolates because they have 83%,91%,and 85%emulsification activity(E_(24))respectively.The results of sequencing confirmed that these three strains(M6,BS-2,and J6)belong to Cobetia marina,Shewanella alga,and Thalassospira permensis re-spectively.Maximum emulsifier production occurred at crude oil concentration(4%,v/v),peptone(2.5 g/L),yeast extract(1.5 g/L),molasses(2%),and at a temperature of 25℃.The results of this research confirmed that the Makran Sea has the potential to reach ro-bust marine bacteria with different biotechnological applications.
基金supported by the Innovation Talents Project of Harbin Science and Technology Bureau(2022CXRCCGO11)。
文摘This study examined the effects of pasteurization(PAS),ultrasonic sterilization(ULS),and microwave sterilization(MWS)on the quality and storage characteristics of brine-fermented tofu(BFT)and fermented tofu(FT).Comparative analysis revealed that MWS had a negligible detrimental effect on the structural integrity and organoleptic properties of BFT and FT,while effectively maintaining its water-holding capacity(WHC)and exhibiting the least impact on its texture.In contrast,PAS and ULS increased hardness and chewiness significantly(P<0.05),but ULS also enhanced the brightness of tofu.Throughout the storage period,the WHC,elasticity,and sensory properties of tofu generally decreased,whereas the hardness and chewiness increased.PAS-BFT and MWS-FT maintained sensory quality for the longest periods of 14 and 12 days respectively,and could be decomposed to more small molecule peptides within 0–8 days and 0–6 days,which are more easily to be absorbed by the body.The findings discovered that MWS is the most suitable method for sterilization of tofu,with superior capability in maintaining the quality,extending shelf life,and improving digestibility of tofu.
基金supported by the National Key Research and Development Program of China(No.2023YFC3402900)the National Nature Science of Foundation(No.61875131)+1 种基金Shenzhen Key Laboratory of Photonics and Biophotonics(No.ZDSYS20210623092006020)Shenzhen Science and Technology Innovation Program(No.20231120175730001)。
文摘Deep learning neural network incorporating surface enhancement Raman scattering technique(SERS)is becoming as a powerful tool for the precise classifications and diagnosis of bacterial infections.However,the large amount of sample requirement and time-consuming sample collection severely hinder its applications.We herein propose a spectral concatenation strategy for residual neural network using nonspecific and specific SERS spectra for the training data augmentation,which is accessible to acquiring larger training dataset with same number of SERS spectra or same size of training dataset with fewer SERS spectra,compared with pure non-specific SERS spectra.With this strategy,the training loss exhibit rapid convergence,and an average accuracy up to 100%in bacteria classifications was achieved with50 SERS spectra for each kind of bacterium;even reduced to 20 SERS spectra per kind of bacterium,classification accuracy is still>95%,demonstrating marked advantage over the results without spectra concatenation.This method can markedly improve the classification accuracy under fewer samples and reduce the data collection workload,and can evidently enhance the performance when used in different machine learning models with high generalization ability.Therefore,this strategy is beneficial for rapid and accurate bacteria classifications with residual neural network.
基金financially supported by the National Key R&D Program of China(No.2020YFD0900201)the Ningbo Public Welfare Technology Application Research Project(No.2022S164)the K.C.Wong Magna Fund in Ningbo University。
文摘Mariculture tailwater poses significant environmental challenges such as water pollution and eutrophication.Photosynthetic bacteria(PSB)have been widely used for pollutant treatment.The integrated aquaculture wastewater bioremediation system(IAWBS)consists of four key components:sedimentation,biofilm,shellfish,and macro-algae.However,there is still some room for improvement in the treatment efficiency of the IAWBS.In this study,PSB(Rhodopseudomonos,Rhodobacteria,Rhodococcus)were added to the system.High-throughput amplicon of 16S rRNA,PERMANOVA,NMDS and other statistical analyses were used to investigate the impacts of PSB.The results showed that significant removal efficiencies of CODMn,NH_(4)^(+)-N,NO_(3)^(-)-N,NO_(2)^(-)-N,PO_(4)^(3-)-P were 71.42%,91.37%,91.72%,87.20%,and 88.80%,respectively.The impact of PSB on bacterioplankton community(BC)was not affected by the time interval but affected by different units,Proteobacteria,Bacteriodia and Actinobacteria were the most abundant phyla in all the units.Alpha diversity underscored a significant decrease in bacterial community diversity due to the PSB.Notably,the PERMANOVA analysis highlighted a significant interaction between the time interval and treated unit,influencing the composition of the microbial community(R^(2)=0.152;P=0.001).This study provides a better understanding of the role of photosynthetic bacteria in an integrated bioremediation system that can effectively treat mariculture tailwater,which is of great significance for the sustainable development of aquaculture.
基金financial support from the Western Light Young Scholars Project,Chinese Academy of Sciences (2022)the Science and Technology Project of Sichuan Province,China (Project No.2021YFG0279)。
文摘Bioremediation is an efficient and popular approach for domestic wastewater treatment while the pollutant discharge standards are difficult to achieve under low-temperature conditions. The application of cold-resistant bacteria has gained increasing attention, but direct introduction to sewage leads to poor environmental adaptability and low microbial activity. Biochar was used as a carrier to immobilize the bacteria to improve microbial survival and activity in this study. The basic physicochemical properties of bacteria immobilized by biochar and ammonium nitrogen removal efficiency were analyzed. The process mechanism of ammonium nitrogen removal was further explored using kinetic fitting and molecular simulation calculations. The results showed that biochar immobilization of cold-resistant bacteria achieved a significantly higher ammonium nitrogen removal rate of 0.88 mg/(L·h) compared to free mixed bacteria(0.74 mg/(L·h)) and biochar alone(0.22 mg/(L·h)). It also exhibited a removal efficiency of 96.56%, which was 15.02% and 72.58% higher than that of free mixed bacteria and biochar, respectively. Adsorption kinetics further revealed that the pseudosecond-order kinetic equation was a better fit for characterizing ammonia-nitrogen removal by biocharimmobilized cold-resistant bacteria. Combining microscopic morphology analysis and molecular simulations demonstrated that enriching functional groups on biochar enhanced its NH_4~+ adsorption capacity by increasing surface activity and polarity, as well as the biodegradation ability of NH_4~+ by improving the interactions between biochar and active enzymes. These findings provide valuable insights into developing more effective ways to improve wastewater treatment efficiency under low temperatures.
基金funded by National Natural Science Foundation of China(32360564)the Natural Science and Technology Innovation Development Multiplication Plan of Guangxi University(2022BZRC010)。
文摘Hyperuricemia(HUA)is characterized by elevated levels of uric acid(UA)in the bloodstream,resulting from either excessive production or insufficient excretion of UA within the body.If left untreated,progressive or persistent HUA can lead to gout,causing significant harm to human health.Lactic acid bacteria(LAB),generally recognized as safe(GRAS)probiotics,have been shown to alleviate symptoms associated with gastrointestinal disorders such as irritable bowel syndrome and inflammatory bowel disease while supporting overall bodily functions and health.Recently,LAB has emerged as a potentially safe,cost-effective and efficient treatment for HUA.This comprehensive review aims to explore the current literature on the mechanisms through which LAB controls HUA.These mechanisms include suppressing purine metabolism,absorbing purine compounds,modulating microbiota to maintain host global purine homeostasis,reducing intestinal permeability,producing metabolites that alleviate HUA symptoms,promoting the expression of urate excretory proteins and inhibiting the expression of urate reabsorption proteins.The findings presented in this review provide a framework for further investigation into how probiotic LAB can alleviate HUA by influencing UA metabolism and elucidating their underlying action mechanisms.