Using fogdrops of OH radicals to eliminate microbial contamination is an effectiveway to solve the current domestic and international problem.The results show that the thresholdof OH solution used in the experiment is...Using fogdrops of OH radicals to eliminate microbial contamination is an effectiveway to solve the current domestic and international problem.The results show that the thresholdof OH solution used in the experiment is 0.6 mg/L,the lethal time is 1 s,and the spray densityof OH solution is 21 μL/m^2.The experimental results show that the OH radical possesses thefollowing advantages:celerity,low lethal concentration and spray density,short lethal time,andabsence of secondary pollution.展开更多
AIM:To seek the cause of Burkholderia cepacia complex(Bcc) infection outbreak and evaluate the efficacy of new methods for nebulizer maintenance. METHODS: We investigated the annual number of Bcc isolates recovered fr...AIM:To seek the cause of Burkholderia cepacia complex(Bcc) infection outbreak and evaluate the efficacy of new methods for nebulizer maintenance. METHODS: We investigated the annual number of Bcc isolates recovered from clinical samples in our hospital between 1999 and 2013. Swab samples were randomly collected for bacterial culture before patient use from 10 each of the two machine types in August 2001; these included 20 samples from each of the following: Drain tubes, operating water chambers, oscillators, and nebulizing chambers. In addition, 10 samples each of nebulizer solutions before and after use were cultured. For environmental investigation, 10 samples were collected from sinks in the nurse stations of the wards where patients positive for Bcc were hospitalized. Numbers of Bcc isolates were compared before and after introduction of new methods for nebulizer maintenance in October 2001. In addition, randomly amplified polymorphic DNA(RAPD) assay was applied to find the genetic divergence of the Bcc isolates obtained from clinical samples and nebulizers. RESULTS: From January 1999 to December 2013, a total of 487 Bcc isolates were obtained from clinical specimens from 181 patients. Notably, 322(66.1%) Bcc isolates were obtained from clinical specimens from 1999 to 2001, including 244(115 patients) from sputum and 34(11 patients) from blood. During this period, 14 isolates were obtained from nebulizer components. Among these, six were derived from nebulizer drain tubes, five from operating water chambers, and one from the oscillator before patient use, and two from nebulizer solutions after patient use. When Bcc was isolated from the nebulizer solution after patient use, Bcc was simultaneously detected in other parts of the nebulizer. Bcc was not isolated from any nebulizer solution before use. RAPD assays revealed similar DNA profiles in isolates obtained from patients and nebulizers. Investigation revealed damaged diaphragms in many nebulizers. The new maintenance methods for nebulizers, including restriction of the usage period, thorough disinfection, and routine check for diaphragm breakage, remarkably reduced Bcc isolation(165 isolates from patients in 12 years and 0 isolate from nebulizers in periodical sampling). In particular, Bcc has been isolated from blood from only one patient since the new methods were introduced.CONCLUSION: Appropriate maintenance of ultrasonic nebulizers is crucial for preventing Bcc contamination of nebulizers and subsequent respiratory tract and blood infections.展开更多
The present study aimed to investigate the microbial populations such a bacteria and fungi contamination present in the herbal medicinal preparations (Lepidium sativum, Nigella sativa, Cuminum cyminum, Foeniculum vulg...The present study aimed to investigate the microbial populations such a bacteria and fungi contamination present in the herbal medicinal preparations (Lepidium sativum, Nigella sativa, Cuminum cyminum, Foeniculum vulgare, Pimpinella anisum, Trigoneela foenum-graecum, Cinnamomum verum, peel coffee, Alchemilla valgaris, Vitex agnus-castus) commonly available in different parts of Riyadh, Saudi Arabia. To determine the contamination of the herbal products, experiments such as total aerobic bacterial plate counts were evaluated by various plating techniques. The isolation and identification of fungi were done using czapek dox agar and potato dextrose agar. The results showed that a total of herbal remedies were contaminated with bacteria and fungi (100%). Among the contaminated products, peel of coffee and Vitex angnus-castus were noted more contamination than the other herbal medicinal plants. The results confirmed that the traditionally prepared herbal medications in Riyadh city are likely to be contaminated with a wide variety of potentially pathogenic bacteria and fungi. Therefore, before consumption, the quality assurance of these products should be thoroughly enforced and monitored in the production and distribution of herbal preparations. In conclusion, the present study gives proper evidence that the consumed herbal products contain different levels of pathogenic microbes.展开更多
In order to provide a reference for the further study of microbial contamination in the pork production process. Microbial contamination of pigs came from three slaughterhouses were detected,and critical control point...In order to provide a reference for the further study of microbial contamination in the pork production process. Microbial contamination of pigs came from three slaughterhouses were detected,and critical control points in the progress of hog slaughter and processing were analyzed. The results showed that microbial contamination existed in the entire slaughter and processing progress,including shower and assassination bloodletting,separation of the internal organs,chopping boards,workshop environment,personal hygiene of the operators,etc.,which should be paid more attention to. The results indicated that reasonable protection measures should be carried out,disinfection awareness of the operators should be improved,and regular disinfection should be ruled under the condition of continuous operation.展开更多
This paper is intended to explore soil organic matter and carbon isotope fractionation at three locations of the Passaic River to determine if microbial degradation of organic contaminants in soil is correlated to the...This paper is intended to explore soil organic matter and carbon isotope fractionation at three locations of the Passaic River to determine if microbial degradation of organic contaminants in soil is correlated to the surrounding physical environment. Microbial degradation of organic contaminants is important for the detoxification of toxic substances thereby minimizing stagnation in the environment and accumulating in the food chain. Since organic contaminants are not easily dissolved in water, they will penetrate sediment and end up enriching the adjacent soil. The hypothesis that we are testing is microbial activity and carbon isotope fractionation will be greater in preserved soils than urban soils. The reason why this is expected to be the case is the expectation of higher microbial activity in preserved environments due to less exposure to pollutants, better soil structure, higher organic matter content, and more favorable conditions for microbial growth. This is contrasted with urban soils, which are impacted by pollutants and disturbances, potentially inhibiting microbial activity. We wish to collect soil samples adjacent to the Passaic River at a pristine location, Great Swamp Wildlife Refuge, a suburban location, Goffle Brook Park, Hawthorne NJ, and an urban location, Paterson NJ. These soil samples will be weighed for soil organic matter (SOM) and weighed for isotope ratio mass spectrometry (IRMS) to test organic carbon isotopes. High SOM and δ13C depletion activity indicate microbial growth based on the characteristics of the soil horizon rather than the location of the soil sample which results in degradation of organic compounds.展开更多
Afforestation has an important role in biodiversity conservation and ecosystem function improvement.A meta-analysis was carried out in China,which has the largest plantation area globally,to quantify the effects of pl...Afforestation has an important role in biodiversity conservation and ecosystem function improvement.A meta-analysis was carried out in China,which has the largest plantation area globally,to quantify the effects of plantings on soil microbial diversity.The results showed that the overall effect of afforestation on soil microbial diversity was positive across the country.Random forest algorithm suggested that soil carbon was the most important factor regulating microbial diversity and the positive response was only found with new plantings on low-carbon bare lands but not on high-carbon farmlands and grasslands.In addition,afforestation with broadleaved species increased microbial diversity,whereas planting with conifers had no effect on microbial diversity.This study clarified the effects of plantings on soil microbial diversity,which has an important implication for establishing appropriate policies and practices to improve the multiple functionalities(e.g.,biodiversity conservation and climate change mitigation)during plantation establishment.展开更多
The World Health Organization states that foodborne diseases are a worldwide public health issue. Although street foods can provide nutritious and affordable ready-to-eat meals for city dwellers, their health risks ca...The World Health Organization states that foodborne diseases are a worldwide public health issue. Although street foods can provide nutritious and affordable ready-to-eat meals for city dwellers, their health risks can outweigh the benefits. A cross-sectional study was conducted in the Bamako district, focusing on street food vendors near schools, universities, extensive markets, administrative centers, and major roads. We aimed to sample fifty (50) sellers per municipality, making 300 sellers for the Bamako district. We developed a survey sheet to collect data, and six teams rotated between the municipalities each month. Before starting the collection, the teams were provided administrative papers approved by the municipal authority. The survey revealed three types of sales sites: fixed (65%), semi-fixed (30%), and mobile (4.40%). The proportion of sellers was 26.8%, 23.2%, 19.7%, and 4.2% in municipalities III, IV, and I. In municipalities I, II, III, IV, and VI, respectively, 92%, 95.70%, 93%, 87.2%, and 100% of the sellers were female. The age distribution of sellers was 65.63%, 46.81%, 40.82%, 38.30%, 36.17%, 36%, and 32% in the 25-34 and 35 - 44 age groups. Illiteracy rates were 59.20%, 61.70%, 55.30%, 75%, and 56% in municipalities I, II, III, IV, and VI, respectively. The study identified two categories of sellers: 48.3% in type 1 and 51.7% in type 2. The first category comprised 154 sellers, and the second 165 sellers. The survey found that 66.00%, 56.00%, 48.90%, 44.90%, 38.30%, and 34.40% of municipal V, VI, III, I, II, and IV sales sites were open-air. In municipality I, 63.30% of the sites were under hangars, while in municipalities II and IV, the corresponding percentages were 51.10% and 59.40%, respectively. Moreover, 46.00%, 31.90%, 31.30%, 30.60%, and 27.70% of the sites in municipalities VI, II, IV, I, and III were located next to gutters. In conclusion, this study identified several factors that could compromise the quality of street foods sold in the six municipalities of Bamako.展开更多
Sugar cane juice is a popular refreshing drink in most part of Bangladesh. It has great taste and health benefits;also it is available most of the public places at reasonable prices which consumed by road side custome...Sugar cane juice is a popular refreshing drink in most part of Bangladesh. It has great taste and health benefits;also it is available most of the public places at reasonable prices which consumed by road side customers including general public, shopping personals, tourists, students. In our country, street vendors crushing sugarcane between roller crusher and sold without any heat treatment or preservative, also served with or without added ice and lemon juice. The study aimed to identify and compare the physico-chemical and microbial quality of sugarcane juice. The chemical qualities of juices including moisture, P<sup>H</sup>, ash, total soluble solid, total sugar, reducing sugar and titrable acidity were found slightly different in Mymensingh, Gazipur and Narayangonj areas. The highest and lowest value of moisture, ash, P<sup>H</sup>, total soluble solids, total sugar, reducing sugar and titrable acidity were found in 84.33% - 79.26% (Gazipur-Mymensingh), 0.57% - 0.04% (Mymensingh-Gazipur), 5.9 - 2.9 (Gazipur-Narayangonj), 17.48% - 4.98% (Mymensingh-Narayangonj), 21.9% - 6.56% (Mymensingh-Gazipur), 3.7 - 2.1 (Gazipur-Mymensingh) and 0.523% - 0.007% (Narayangonj-Gazipur) respectively. For microbiological analysis, the total viable count of sugar cane juice in Mymensingh, Gazipur and Narayangonj were ranged from 0.6 × 10<sup>5</sup> - 43.6 × 10<sup>5</sup> cfu/ml, 4.6 × 10<sup>5</sup> - 21.6 × 10<sup>5</sup> cfu/ml and 3.6 × 10<sup>5</sup> - 36.6 × 10<sup>5</sup> cfu/ml respectively, where the permitted value is 1.0 × 10<sup>4</sup> cfu/ml, whereas the total coliform count was ranged from 0.4 × 10<sup>5</sup> - 6.4 × 10<sup>5</sup> cfu/ml, 0.6 × 10<sup>5</sup> - 8.4 × 10<sup>5</sup> cfu/ml and 0.00 - 8.4 × 10<sup>5</sup> cfu/ml, where the permitted value is 100 cfu/ml and total fungal count was ranged from 5.5 × 10<sup>5</sup> - 56.5 × 10<sup>5</sup> cfu/ml, 21.5 × 10<sup>5</sup> - 54.5 × 10<sup>5</sup> cfu/ml and 32.5 × 10<sup>5</sup> - 68.5 × 10<sup>5</sup> cfu/ml, where the permitted value is 1000 cfu/ml. According to the Gulf standard, the microbiological parameters of all the collected sugar cane juice were out of the permitted standards, so that a serious health outbreak can be caused anytime.展开更多
The paper reviews previous publications and reports some comments about a semi empirical model of the growth and decay process of a planktonic microbial culture. After summarizing and reshaping some fundamental mathem...The paper reviews previous publications and reports some comments about a semi empirical model of the growth and decay process of a planktonic microbial culture. After summarizing and reshaping some fundamental mathematical expressions, the paper highlights the reasons for the choice of a suitable time origin that makes the parameters of the model self-consistent. Besides the potential applications to predictive microbiology studies and to effects of bactericidal drugs, the model allows a suitable proxy of the fitness of the microbial culture, which can be of interest for the studies on the evolution across some thousand generations of a Long Term Evolution Experiment.展开更多
Current globalization trends and important breakthroughs globally need a complete study of heavy metal contamination, its causes, its impacts on human and environmental health, and different remediation strategies. He...Current globalization trends and important breakthroughs globally need a complete study of heavy metal contamination, its causes, its impacts on human and environmental health, and different remediation strategies. Heavy metal pollution is mostly produced by urbanization and industry, which threatens ecosystems and human health. Herein, we discuss a sustainable environmental restoration strategy employing phytoremediation for heavy metal pollution, the carcinogenic, mutagenic, and cytotoxic effects of heavy metals such as cadmium, copper, mercury, selenium, zinc, arsenic, chromium, lead, nickel, and silver, which may be fatal. Phytoremediation, which was prioritized, uses plants to remove, accumulate, and depollute pollutants. This eco-friendly method may safely collect, accumulate, and detoxify toxins using plants, making it popular. This study covers phytostabilization, phytodegradation, rhizodegradation, phytoextraction, phytovolatilization, and rhizofiltration. A phytoremediation process’s efficiency in varied environmental circumstances depends on these components’ complex interplay. This paper also introduces developing phytoremediation approaches including microbe-assisted, chemical-assisted, and organic or bio-char use. These advancements attempt to overcome conventional phytoremediation’s limitations, such as limited suitable plant species, location problems, and sluggish remediation. Current research includes machine learning techniques and computer modeling, biostimulation, genetic engineering, bioaugmentation, and hybrid remediation. These front-line solutions show that phytoremediation research is developing towards transdisciplinary efficiency enhancement. We acknowledge phytoremediation’s promise but also its drawbacks, such as site-specific variables, biomass buildup, and sluggish remediation, as well as ongoing research to address them. In conclusion, heavy metal pollution threatens the ecology and public health and must be reduced. Phytoremediation treats heavy metal pollution in different ways. Over time, phytoremediation systems have developed unique ways that improve efficiency. Despite difficulties like site-specificity, sluggish remediation, and biomass buildup potential, phytoremediation is still a vital tool for environmental sustainability.展开更多
Land use change affects the balance of organic carbon(C)reserves and the global C cycle.Microbial residues are essential constituents of stable soil organic C(SOC).However,it remains unclear how microbial residue chan...Land use change affects the balance of organic carbon(C)reserves and the global C cycle.Microbial residues are essential constituents of stable soil organic C(SOC).However,it remains unclear how microbial residue changes over time following afforestation.In this study,16-,23-,52-,and 62-year-old Mongolian pine stands and 16-year-old cropland were studied in the Horqin Sandy Land,China.We analyzed changes in SOC,amino sugar content,and microbial parameters to assess how microbial communities influence soil C transformation and preservation.The results showed that SOC storage increased with stand age in the early stage of afforestation but remained unchanged at about 1.27-1.29 kg/m2 after 52 a.Moreover,there were consistent increases in amino sugars and microbial residues with increasing stand age.As stand age increased from 16 to 62 a,soil pH decreased from 6.84 to 5.71,and the concentration of total amino sugars increased from 178.53 to 509.99 mg/kg.A significant negative correlation between soil pH and the concentration of specific and total amino sugars was observed,indicating that the effects of soil acidification promote amino sugar stabilization during afforestation.In contrast to the Mongolian pine plantation of the same age,the cropland accumulated more SOC and microbial residues because of fertilizer application.Across Mongolian pine plantation with different ages,there was no significant change in calculated contribution of bacterial or fungal residues to SOC,suggesting that fungi were consistently the dominant contributors to SOC with increasing time.Our results indicate that afforestation in the Horqin Sandy Land promotes efficient microbial growth and residue accumulation in SOC stocks and has a consistent positive impact on SOC persistence.展开更多
The spatiotemporal distributions of microbes in soil by different methods could affect the efficacy of the microbes to reduce the soil hydraulic conductivity.In this study,the specimens of bio-mediated sands were prep...The spatiotemporal distributions of microbes in soil by different methods could affect the efficacy of the microbes to reduce the soil hydraulic conductivity.In this study,the specimens of bio-mediated sands were prepared using three different methods,i.e.injecting,mixing,and pouring a given microbial so-lution onto compacted sand specimens.The hydraulic conductivity was measured by constant-head tests,while any soil microstructural changes due to addition of the microbes were observed by scan-ning electron microscope(SEM)and mercury intrusion porosimetry(MIP)tests.The amount of dextran concentration produced by microbes in each type of specimen was quantified by a refractometer.Results show that dextran production increased exponentially after 5-7 d of microbial settling with the supply of culture medium.The injection and mixing methods resulted in a similar amount and uniform dis-tribution of dextran in the specimens.The pouring method,however,produced a nonuniform distri-bution,with a higher concentration near the specimen surface.As the supply of culture medium discontinued,the dextran content near the surface produced by the pouring method decreased dramatically due to high competition for nutrients with foreign colonies.Average dextran concentration was negatively and correlated with hydraulic conductivity of bio-mediated soils exponentially,due to the clogging of large soil pores by dextran.The hydraulic conductivity of the injection and mixing cases did not change significantly when the supply of culture medium was absent.展开更多
Bidens pilosa is recognized as one of the major invasive plants in China.Its invasion has been associated with significant losses in agriculture,forestry,husbandry,and biodiversity.Soil ecosystems play an important ro...Bidens pilosa is recognized as one of the major invasive plants in China.Its invasion has been associated with significant losses in agriculture,forestry,husbandry,and biodiversity.Soil ecosystems play an important role in alien plant invasion.Microorganisms within the soil act as intermediaries between plants and soil ecological functions,playing a role in regulating soil enzyme activities and nutrient dynamics.Understanding the interactions between invasive plants,soil microorganisms,and soil ecological processes is vital for managing and mitigating the impacts of invasive species on the environment.In this study,we conducted a systematic analysis focusing on B.pilosa and Setaria viridis,a common native companion plant in the invaded area.To simulate the invasion process of B.pilosa,we constructed homogeneous plots consisting of B.pilosa and S.viridis grown separately as monocultures,as well as in mixtures.The rhizosphere and bulk soils were collected from the alien plant B.pilosa and the native plant S.viridis.In order to focus on the soil ecological functional mechanisms that contribute to the successful invasion of B.pilosa,we analyzed the effects of B.pilosa on the composition of soil microbial communities and soil ecological functions.The results showed that the biomass of B.pilosa increased by 27.51% and that of S.viridis was significantly reduced by 66.56%.The organic matter contents in the bulk and rhizosphere soils of B.pilosa were approximately 1.30 times those in the native plant soils.The TN and NO_(3)^(-)contents in the rhizosphere soil of B.pilosa were 1.30 to 2.71 times those in the native plant soils.The activities of acid phosphatase,alkaline phosphatase,and urease in the rhizosphere soil of B.pilosa were 1.98-2.25 times higher than in the native plant soils.Using high-throughput sequencing of the16S rRNA gene,we found that B.pilosa altered the composition of the soil microbial community.Specifically,many genera in Actinobacteria and Proteobacteria were enriched in B.pilosa soils.Further correlation analyses verified that these genera had significantly positive relationships with soil nutrients and enzyme activities.Plant biomass,soil p H,and the contents of organic matter,TN,NO_(3)^(-),TP,AP,TK,and AK were the main factors affecting soil microbial communities.This study showed that the invasion of B.pilosa led to significant alterations in the composition of the soil microbial communities.These changes were closely linked to modifications in plant traits as well as soil physical and chemical properties.Some microbial species related to C,N and P cycling were enriched in the soil invaded by B.pilosa.These findings provide additional support for the hypothesis of soil-microbe feedback in the successful invasion of alien plants.They also offer insights into the ecological mechanism by which soil microbes contribute to the successful invasion of B.pilosa.Overall,our research contributes to a better understanding of the complex interactions between invasive plants,soil microbial communities,and ecosystem dynamics.展开更多
In the Loess Plateau of China,land-use pattern is a major factor in controlling underlying biological processes.Additionally,the process of land-use pattern was accompanied by abandoned lands,potentially impacting soi...In the Loess Plateau of China,land-use pattern is a major factor in controlling underlying biological processes.Additionally,the process of land-use pattern was accompanied by abandoned lands,potentially impacting soil microbe.However,limited researches were conducted to study the impacts of land-use patterns on the diversity and community of soil microorganisms in this area.The study aimed to investigate soil microbial community diversity and composition using high-throughput deoxyribonucleic acid(DNA)sequencing under different land-use patterns(apricot tree land,apple tree land,peach tree land,corn land,and abandoned land).The results showed a substantial difference(P<0.050)in bacterial alpha-diversity and beta-diversity between abandoned land and other land-use patterns,with the exception of Shannon index.While fungal beta-diversity was not considerably impacted by land-use patterns,fungal alpha-diversity indices varied significantly.The relative abundance of Actinobacteriota(34.90%),Proteobacteria(20.65%),and Ascomycota(77.42%)varied in soils with different land-use patterns.Soil pH exerted a dominant impact on the soil bacterial communities'composition,whereas soil available phosphorus was the main factor shaping the soil fungal communities'composition.These findings suggest that variations in land-use pattern had resulted in changes to soil properties,subsequently impacting diversity and structure of microbial community in the Loess Plateau.Given the strong interdependence between soil and its microbiota,it is imperative to reclaim abandoned lands to maintain soil fertility and sustain its function,which will have significant ecological service implications,particularly with regards to soil conservation in ecologically vulnerable areas.展开更多
Free amino acid(FAA)is the important component of vinegar that infl uences quality perception and consumer acceptance.FAA is one of the major metabolites produced by microorganisms;however,the microbial metabolic netw...Free amino acid(FAA)is the important component of vinegar that infl uences quality perception and consumer acceptance.FAA is one of the major metabolites produced by microorganisms;however,the microbial metabolic network on FAA biosynthesis remains unclear.Through metagenomic analysis,this work aimed to elucidate the roles of microbes in FAA biosynthesis during Monascus rice vinegar fermentation.Taxonomic profiles from functional analyses showed 14 dominant genera with high contributions to the metabolism pathways.The metabolic network for FAA biosynthesis was then constructed,and the microbial distribution in different metabolic pathways was illuminated.The results revealed that 5 functional genera were closely involved in FAA biosynthesis.This study illuminated the metabolic roles of microorganisms in FAA biosynthesis and provided crucial insights into the functional attributes of microbiota in vinegar fermentation.展开更多
Lipocalin 2(LCN2)plays a pivotal role in iron metabolism,particularly in the context of microbial infection resistance(e.g.,viruses,bacteria,parasites,etc.).LCN2 combats microbial infection by directly assisting the b...Lipocalin 2(LCN2)plays a pivotal role in iron metabolism,particularly in the context of microbial infection resistance(e.g.,viruses,bacteria,parasites,etc.).LCN2 combats microbial infection by directly assisting the body in competing with microorganisms for iron,inducing immune cells to secrete various cytokines to enhance systemic immune responses,or recruiting neutrophils to infectious sites.The liver serves as the primary organ for LCN2 secretion during microbial infections.This review encapsulates recent advances in dynamic changes,clinical values,and the effects of LCN2 in infectious liver diseases caused by various microbial microorganisms.展开更多
Objective: The main objective of this study was to assess the degree of contamination of surface waters by heavy metals and pesticides. Method: To this end, data were collected in December 2022 from four specific samp...Objective: The main objective of this study was to assess the degree of contamination of surface waters by heavy metals and pesticides. Method: To this end, data were collected in December 2022 from four specific sampling stations: Okpara, Térou, Affon and Adjiro. Levels of heavy metals, including cadmium, chromium, copper, iron, mercury, nickel and lead, were measured and subjected to in-depth statistical analysis using graphical summation models. In addition, the concentrations of pesticide active ingredients present in the samples were interpreted and evaluated. The statistical data collected during this study were processed using R software, version 3.5.0. Results: The values obtained at the different stations Okpara, Térou, Affon and Adjiro are respectively Arsenic (2 × 10<sup>-4</sup> mg/L;2.2 × 10<sup>-1</sup> mg/L;1.2 × 10<sup>-4</sup> mg/L;2 × 10<sup>-4</sup> mg/L), Cadmium (4.4 × 10<sup>-5</sup> mg/L;1.1 × 10<sup>-2</sup> mg/L;10<sup>-4</sup> mg/L;4 × 10<sup>-4</sup> mg/L). Then Copper (7 × 10<sup>-4</sup> mg/L;3 × 10<sup>-3</sup> mg/L;7 × 10<sup>-4</sup> mg/L;1 × 10<sup>-4</sup> mg/L), Iron (1.51 mg/L;6.4 × 10<sup>-1</sup> mg/L;2.0012 mg/L;2.9 × 10<sup>-1</sup> mg/L), Lead (0 mg/L;0 mg/L;1.5 × 10<sup>-3</sup> mg/L;1.5 × 10<sup>-3</sup> mg/L). Mercury, nickel and chromium were not detected in surface waters. It is important to note that the values obtained for trace metals (Cadmium, Chromium, Copper, Iron, Mercury, nickel and chromium were not detected in surface waters. It is important to note that the values obtained for trace metals (cadmium, chromium, copper, iron, mercury, nickel and lead) were all below the guideline standards set by the WHO in 2006 for uncontaminated surface waters. This indicates that the surface waters of the Upper Ouémé were below acceptable contamination thresholds in terms of heavy metals. However, the presence of pesticide active ingredients such as cyfluthrin, endosulfan-alpha, endosulfan-beta, profenosfos, tihan, atrazine, gala super and glycel clearly indicates that these surface waters are subject to agricultural contamination.展开更多
Background:It is possible that preservative-free eye drops can be contaminated.The aim of this study was to assess the incidence of microbial contamination of preservative-free hospital-prepared anti-infective eye dro...Background:It is possible that preservative-free eye drops can be contaminated.The aim of this study was to assess the incidence of microbial contamination of preservative-free hospital-prepared anti-infective eye drops and investigate factors that contribute to contamination.This finding may help to raise awareness of this problem to medical healthcare staff and patients in order to prevent the transmission of microorganisms from eye drops to the patients through treatment of pre-existing eye diseases.Methods:Two hundred and ninety-five eye drop bottles were collected from patients attending Rajavithi Hospital Ophthalmologic outpatient and inpatient department,including both those used by patients at home and those administered in the hospital by medical staff.Samples were taken from the tips of droppers and bottles,and the residual fluid inside the bottles was then cultivated onto different culture plates.The culture results were identified and analyzed according to various factors related to both individual users and the bottles.Results:Seven different types of eye drops were collected and 71(24.06%)of the 295 bottles were contaminated.Vancomycin eye drops were the most contaminated.Twenty-six different types of pathogens were identified,most frequently mold(42.98%),and the amount of contamination was higher in tips than in residual fluid inside the bottle.There was no statistically significant difference in contamination between patients used eye drops collected in outpatient units(32.14%)and medical staff used eye drops collected in inpatient settings(23.22%).The only factor that was statistically significant was the number of eye drops used per person.We found that samples from patients who used only up to 2 eye drops suffered contamination(42.8%)more than those from their counterparts who used at least 3(22.18%),P¼0.02.Conclusions:Of these preservative-free hospital preparations anti-infective eye drops,24.06%were contaminated.The number of eye drops used per person was statistically significant in triggering contamination.There is a possibility of number of eyedrops use person may trigger contamination.展开更多
This study investigated the microbial contamination of ice cream in China.A total of 2887 ice cream samples were collected from different regions of China.Contamination by the aerobic plate count(APC),coliforms,and th...This study investigated the microbial contamination of ice cream in China.A total of 2887 ice cream samples were collected from different regions of China.Contamination by the aerobic plate count(APC),coliforms,and three foodborne pathogens,Listeria monocytogenes(L.monocytogenes),Staphylococcus aureus(S.aureus),and Salmonella spp.,was detected in the samples.L.monocytogenes isolates were further analyzed for antibiotic susceptibility and multi-locus sequence typing(MLST).The results showed that APC was more than 10^(5) colony forming units(CFU)/g in 6.10%(176/2887)and coliform was more than 10^(2) CFU/g in 15.69%(453/2887)of all samples.The positive rates of S.aureus,L.monocytogenes,and Salmonella spp.were 0.66%,0.62%,and 0.10%,respectively.Among these,S.aureus contamination was more than 102 CFU/g in two samples,and L.monocytogenes in the positive sample was in the range of 0.3-240 most probable number(MPN)/g.with a median of 4.3 MPN/g.The hygienic status of the packaged samples was much better than that of the bulk samples(P<0.05).Catering samples were more frequently and heavily contaminated than samples from retail and wholesale outlets(P<0.05).No significant differences were observed in samples bought from urban and rural areas(P>0.05).For 18 L.monocytogenes strains isolated from ice cream,the resistance rate of nine antibiotics was 5.56%(1/18).By MLST,the L.monocytogenes strains were classified into nine sequence types(STs),of which ST8 was the most common(six isolates).These results indicate that a potential health risk to the public may be caused by ice cream,particularly in susceptiblepopulations.展开更多
基金National Natural Science Foundation of China(Nos.50578020,60471036)
文摘Using fogdrops of OH radicals to eliminate microbial contamination is an effectiveway to solve the current domestic and international problem.The results show that the thresholdof OH solution used in the experiment is 0.6 mg/L,the lethal time is 1 s,and the spray densityof OH solution is 21 μL/m^2.The experimental results show that the OH radical possesses thefollowing advantages:celerity,low lethal concentration and spray density,short lethal time,andabsence of secondary pollution.
文摘AIM:To seek the cause of Burkholderia cepacia complex(Bcc) infection outbreak and evaluate the efficacy of new methods for nebulizer maintenance. METHODS: We investigated the annual number of Bcc isolates recovered from clinical samples in our hospital between 1999 and 2013. Swab samples were randomly collected for bacterial culture before patient use from 10 each of the two machine types in August 2001; these included 20 samples from each of the following: Drain tubes, operating water chambers, oscillators, and nebulizing chambers. In addition, 10 samples each of nebulizer solutions before and after use were cultured. For environmental investigation, 10 samples were collected from sinks in the nurse stations of the wards where patients positive for Bcc were hospitalized. Numbers of Bcc isolates were compared before and after introduction of new methods for nebulizer maintenance in October 2001. In addition, randomly amplified polymorphic DNA(RAPD) assay was applied to find the genetic divergence of the Bcc isolates obtained from clinical samples and nebulizers. RESULTS: From January 1999 to December 2013, a total of 487 Bcc isolates were obtained from clinical specimens from 181 patients. Notably, 322(66.1%) Bcc isolates were obtained from clinical specimens from 1999 to 2001, including 244(115 patients) from sputum and 34(11 patients) from blood. During this period, 14 isolates were obtained from nebulizer components. Among these, six were derived from nebulizer drain tubes, five from operating water chambers, and one from the oscillator before patient use, and two from nebulizer solutions after patient use. When Bcc was isolated from the nebulizer solution after patient use, Bcc was simultaneously detected in other parts of the nebulizer. Bcc was not isolated from any nebulizer solution before use. RAPD assays revealed similar DNA profiles in isolates obtained from patients and nebulizers. Investigation revealed damaged diaphragms in many nebulizers. The new maintenance methods for nebulizers, including restriction of the usage period, thorough disinfection, and routine check for diaphragm breakage, remarkably reduced Bcc isolation(165 isolates from patients in 12 years and 0 isolate from nebulizers in periodical sampling). In particular, Bcc has been isolated from blood from only one patient since the new methods were introduced.CONCLUSION: Appropriate maintenance of ultrasonic nebulizers is crucial for preventing Bcc contamination of nebulizers and subsequent respiratory tract and blood infections.
文摘The present study aimed to investigate the microbial populations such a bacteria and fungi contamination present in the herbal medicinal preparations (Lepidium sativum, Nigella sativa, Cuminum cyminum, Foeniculum vulgare, Pimpinella anisum, Trigoneela foenum-graecum, Cinnamomum verum, peel coffee, Alchemilla valgaris, Vitex agnus-castus) commonly available in different parts of Riyadh, Saudi Arabia. To determine the contamination of the herbal products, experiments such as total aerobic bacterial plate counts were evaluated by various plating techniques. The isolation and identification of fungi were done using czapek dox agar and potato dextrose agar. The results showed that a total of herbal remedies were contaminated with bacteria and fungi (100%). Among the contaminated products, peel of coffee and Vitex angnus-castus were noted more contamination than the other herbal medicinal plants. The results confirmed that the traditionally prepared herbal medications in Riyadh city are likely to be contaminated with a wide variety of potentially pathogenic bacteria and fungi. Therefore, before consumption, the quality assurance of these products should be thoroughly enforced and monitored in the production and distribution of herbal preparations. In conclusion, the present study gives proper evidence that the consumed herbal products contain different levels of pathogenic microbes.
文摘In order to provide a reference for the further study of microbial contamination in the pork production process. Microbial contamination of pigs came from three slaughterhouses were detected,and critical control points in the progress of hog slaughter and processing were analyzed. The results showed that microbial contamination existed in the entire slaughter and processing progress,including shower and assassination bloodletting,separation of the internal organs,chopping boards,workshop environment,personal hygiene of the operators,etc.,which should be paid more attention to. The results indicated that reasonable protection measures should be carried out,disinfection awareness of the operators should be improved,and regular disinfection should be ruled under the condition of continuous operation.
文摘This paper is intended to explore soil organic matter and carbon isotope fractionation at three locations of the Passaic River to determine if microbial degradation of organic contaminants in soil is correlated to the surrounding physical environment. Microbial degradation of organic contaminants is important for the detoxification of toxic substances thereby minimizing stagnation in the environment and accumulating in the food chain. Since organic contaminants are not easily dissolved in water, they will penetrate sediment and end up enriching the adjacent soil. The hypothesis that we are testing is microbial activity and carbon isotope fractionation will be greater in preserved soils than urban soils. The reason why this is expected to be the case is the expectation of higher microbial activity in preserved environments due to less exposure to pollutants, better soil structure, higher organic matter content, and more favorable conditions for microbial growth. This is contrasted with urban soils, which are impacted by pollutants and disturbances, potentially inhibiting microbial activity. We wish to collect soil samples adjacent to the Passaic River at a pristine location, Great Swamp Wildlife Refuge, a suburban location, Goffle Brook Park, Hawthorne NJ, and an urban location, Paterson NJ. These soil samples will be weighed for soil organic matter (SOM) and weighed for isotope ratio mass spectrometry (IRMS) to test organic carbon isotopes. High SOM and δ13C depletion activity indicate microbial growth based on the characteristics of the soil horizon rather than the location of the soil sample which results in degradation of organic compounds.
基金supported by the National Key Research and Development Program of China(2021YFD2200401)the National Natural Science Foundation of China(31901293)。
文摘Afforestation has an important role in biodiversity conservation and ecosystem function improvement.A meta-analysis was carried out in China,which has the largest plantation area globally,to quantify the effects of plantings on soil microbial diversity.The results showed that the overall effect of afforestation on soil microbial diversity was positive across the country.Random forest algorithm suggested that soil carbon was the most important factor regulating microbial diversity and the positive response was only found with new plantings on low-carbon bare lands but not on high-carbon farmlands and grasslands.In addition,afforestation with broadleaved species increased microbial diversity,whereas planting with conifers had no effect on microbial diversity.This study clarified the effects of plantings on soil microbial diversity,which has an important implication for establishing appropriate policies and practices to improve the multiple functionalities(e.g.,biodiversity conservation and climate change mitigation)during plantation establishment.
文摘The World Health Organization states that foodborne diseases are a worldwide public health issue. Although street foods can provide nutritious and affordable ready-to-eat meals for city dwellers, their health risks can outweigh the benefits. A cross-sectional study was conducted in the Bamako district, focusing on street food vendors near schools, universities, extensive markets, administrative centers, and major roads. We aimed to sample fifty (50) sellers per municipality, making 300 sellers for the Bamako district. We developed a survey sheet to collect data, and six teams rotated between the municipalities each month. Before starting the collection, the teams were provided administrative papers approved by the municipal authority. The survey revealed three types of sales sites: fixed (65%), semi-fixed (30%), and mobile (4.40%). The proportion of sellers was 26.8%, 23.2%, 19.7%, and 4.2% in municipalities III, IV, and I. In municipalities I, II, III, IV, and VI, respectively, 92%, 95.70%, 93%, 87.2%, and 100% of the sellers were female. The age distribution of sellers was 65.63%, 46.81%, 40.82%, 38.30%, 36.17%, 36%, and 32% in the 25-34 and 35 - 44 age groups. Illiteracy rates were 59.20%, 61.70%, 55.30%, 75%, and 56% in municipalities I, II, III, IV, and VI, respectively. The study identified two categories of sellers: 48.3% in type 1 and 51.7% in type 2. The first category comprised 154 sellers, and the second 165 sellers. The survey found that 66.00%, 56.00%, 48.90%, 44.90%, 38.30%, and 34.40% of municipal V, VI, III, I, II, and IV sales sites were open-air. In municipality I, 63.30% of the sites were under hangars, while in municipalities II and IV, the corresponding percentages were 51.10% and 59.40%, respectively. Moreover, 46.00%, 31.90%, 31.30%, 30.60%, and 27.70% of the sites in municipalities VI, II, IV, I, and III were located next to gutters. In conclusion, this study identified several factors that could compromise the quality of street foods sold in the six municipalities of Bamako.
文摘Sugar cane juice is a popular refreshing drink in most part of Bangladesh. It has great taste and health benefits;also it is available most of the public places at reasonable prices which consumed by road side customers including general public, shopping personals, tourists, students. In our country, street vendors crushing sugarcane between roller crusher and sold without any heat treatment or preservative, also served with or without added ice and lemon juice. The study aimed to identify and compare the physico-chemical and microbial quality of sugarcane juice. The chemical qualities of juices including moisture, P<sup>H</sup>, ash, total soluble solid, total sugar, reducing sugar and titrable acidity were found slightly different in Mymensingh, Gazipur and Narayangonj areas. The highest and lowest value of moisture, ash, P<sup>H</sup>, total soluble solids, total sugar, reducing sugar and titrable acidity were found in 84.33% - 79.26% (Gazipur-Mymensingh), 0.57% - 0.04% (Mymensingh-Gazipur), 5.9 - 2.9 (Gazipur-Narayangonj), 17.48% - 4.98% (Mymensingh-Narayangonj), 21.9% - 6.56% (Mymensingh-Gazipur), 3.7 - 2.1 (Gazipur-Mymensingh) and 0.523% - 0.007% (Narayangonj-Gazipur) respectively. For microbiological analysis, the total viable count of sugar cane juice in Mymensingh, Gazipur and Narayangonj were ranged from 0.6 × 10<sup>5</sup> - 43.6 × 10<sup>5</sup> cfu/ml, 4.6 × 10<sup>5</sup> - 21.6 × 10<sup>5</sup> cfu/ml and 3.6 × 10<sup>5</sup> - 36.6 × 10<sup>5</sup> cfu/ml respectively, where the permitted value is 1.0 × 10<sup>4</sup> cfu/ml, whereas the total coliform count was ranged from 0.4 × 10<sup>5</sup> - 6.4 × 10<sup>5</sup> cfu/ml, 0.6 × 10<sup>5</sup> - 8.4 × 10<sup>5</sup> cfu/ml and 0.00 - 8.4 × 10<sup>5</sup> cfu/ml, where the permitted value is 100 cfu/ml and total fungal count was ranged from 5.5 × 10<sup>5</sup> - 56.5 × 10<sup>5</sup> cfu/ml, 21.5 × 10<sup>5</sup> - 54.5 × 10<sup>5</sup> cfu/ml and 32.5 × 10<sup>5</sup> - 68.5 × 10<sup>5</sup> cfu/ml, where the permitted value is 1000 cfu/ml. According to the Gulf standard, the microbiological parameters of all the collected sugar cane juice were out of the permitted standards, so that a serious health outbreak can be caused anytime.
文摘The paper reviews previous publications and reports some comments about a semi empirical model of the growth and decay process of a planktonic microbial culture. After summarizing and reshaping some fundamental mathematical expressions, the paper highlights the reasons for the choice of a suitable time origin that makes the parameters of the model self-consistent. Besides the potential applications to predictive microbiology studies and to effects of bactericidal drugs, the model allows a suitable proxy of the fitness of the microbial culture, which can be of interest for the studies on the evolution across some thousand generations of a Long Term Evolution Experiment.
文摘Current globalization trends and important breakthroughs globally need a complete study of heavy metal contamination, its causes, its impacts on human and environmental health, and different remediation strategies. Heavy metal pollution is mostly produced by urbanization and industry, which threatens ecosystems and human health. Herein, we discuss a sustainable environmental restoration strategy employing phytoremediation for heavy metal pollution, the carcinogenic, mutagenic, and cytotoxic effects of heavy metals such as cadmium, copper, mercury, selenium, zinc, arsenic, chromium, lead, nickel, and silver, which may be fatal. Phytoremediation, which was prioritized, uses plants to remove, accumulate, and depollute pollutants. This eco-friendly method may safely collect, accumulate, and detoxify toxins using plants, making it popular. This study covers phytostabilization, phytodegradation, rhizodegradation, phytoextraction, phytovolatilization, and rhizofiltration. A phytoremediation process’s efficiency in varied environmental circumstances depends on these components’ complex interplay. This paper also introduces developing phytoremediation approaches including microbe-assisted, chemical-assisted, and organic or bio-char use. These advancements attempt to overcome conventional phytoremediation’s limitations, such as limited suitable plant species, location problems, and sluggish remediation. Current research includes machine learning techniques and computer modeling, biostimulation, genetic engineering, bioaugmentation, and hybrid remediation. These front-line solutions show that phytoremediation research is developing towards transdisciplinary efficiency enhancement. We acknowledge phytoremediation’s promise but also its drawbacks, such as site-specific variables, biomass buildup, and sluggish remediation, as well as ongoing research to address them. In conclusion, heavy metal pollution threatens the ecology and public health and must be reduced. Phytoremediation treats heavy metal pollution in different ways. Over time, phytoremediation systems have developed unique ways that improve efficiency. Despite difficulties like site-specificity, sluggish remediation, and biomass buildup potential, phytoremediation is still a vital tool for environmental sustainability.
基金funded by the Fundamental Research Funds of Chinese Academy of Forestry(CAF)(CAFYBB2020QD002-2).
文摘Land use change affects the balance of organic carbon(C)reserves and the global C cycle.Microbial residues are essential constituents of stable soil organic C(SOC).However,it remains unclear how microbial residue changes over time following afforestation.In this study,16-,23-,52-,and 62-year-old Mongolian pine stands and 16-year-old cropland were studied in the Horqin Sandy Land,China.We analyzed changes in SOC,amino sugar content,and microbial parameters to assess how microbial communities influence soil C transformation and preservation.The results showed that SOC storage increased with stand age in the early stage of afforestation but remained unchanged at about 1.27-1.29 kg/m2 after 52 a.Moreover,there were consistent increases in amino sugars and microbial residues with increasing stand age.As stand age increased from 16 to 62 a,soil pH decreased from 6.84 to 5.71,and the concentration of total amino sugars increased from 178.53 to 509.99 mg/kg.A significant negative correlation between soil pH and the concentration of specific and total amino sugars was observed,indicating that the effects of soil acidification promote amino sugar stabilization during afforestation.In contrast to the Mongolian pine plantation of the same age,the cropland accumulated more SOC and microbial residues because of fertilizer application.Across Mongolian pine plantation with different ages,there was no significant change in calculated contribution of bacterial or fungal residues to SOC,suggesting that fungi were consistently the dominant contributors to SOC with increasing time.Our results indicate that afforestation in the Horqin Sandy Land promotes efficient microbial growth and residue accumulation in SOC stocks and has a consistent positive impact on SOC persistence.
基金The first author(V.Kamchoom)acknowledges the grant(Grant No.FRB66065/0258-RE-KRIS/FF66/53)from King Mongkut’s Insti-tute of Technology Ladkrabang(KMITL)and National Science,Research and Innovation Fund(NSRF)the grant under Climate Change and Climate Variability Research in Monsoon Asia(CMON3)from the National Research Council of Thailand(NRCT)(Grant No.N10A650844)the National Natural Science Foundation of China(NSFC).
文摘The spatiotemporal distributions of microbes in soil by different methods could affect the efficacy of the microbes to reduce the soil hydraulic conductivity.In this study,the specimens of bio-mediated sands were prepared using three different methods,i.e.injecting,mixing,and pouring a given microbial so-lution onto compacted sand specimens.The hydraulic conductivity was measured by constant-head tests,while any soil microstructural changes due to addition of the microbes were observed by scan-ning electron microscope(SEM)and mercury intrusion porosimetry(MIP)tests.The amount of dextran concentration produced by microbes in each type of specimen was quantified by a refractometer.Results show that dextran production increased exponentially after 5-7 d of microbial settling with the supply of culture medium.The injection and mixing methods resulted in a similar amount and uniform dis-tribution of dextran in the specimens.The pouring method,however,produced a nonuniform distri-bution,with a higher concentration near the specimen surface.As the supply of culture medium discontinued,the dextran content near the surface produced by the pouring method decreased dramatically due to high competition for nutrients with foreign colonies.Average dextran concentration was negatively and correlated with hydraulic conductivity of bio-mediated soils exponentially,due to the clogging of large soil pores by dextran.The hydraulic conductivity of the injection and mixing cases did not change significantly when the supply of culture medium was absent.
基金funded by the National Key R&D Program of China(2022YFC2601100,2021YFD1400100 and 2021YFC2600400)the National Natural Science Foundation of China(42207162)。
文摘Bidens pilosa is recognized as one of the major invasive plants in China.Its invasion has been associated with significant losses in agriculture,forestry,husbandry,and biodiversity.Soil ecosystems play an important role in alien plant invasion.Microorganisms within the soil act as intermediaries between plants and soil ecological functions,playing a role in regulating soil enzyme activities and nutrient dynamics.Understanding the interactions between invasive plants,soil microorganisms,and soil ecological processes is vital for managing and mitigating the impacts of invasive species on the environment.In this study,we conducted a systematic analysis focusing on B.pilosa and Setaria viridis,a common native companion plant in the invaded area.To simulate the invasion process of B.pilosa,we constructed homogeneous plots consisting of B.pilosa and S.viridis grown separately as monocultures,as well as in mixtures.The rhizosphere and bulk soils were collected from the alien plant B.pilosa and the native plant S.viridis.In order to focus on the soil ecological functional mechanisms that contribute to the successful invasion of B.pilosa,we analyzed the effects of B.pilosa on the composition of soil microbial communities and soil ecological functions.The results showed that the biomass of B.pilosa increased by 27.51% and that of S.viridis was significantly reduced by 66.56%.The organic matter contents in the bulk and rhizosphere soils of B.pilosa were approximately 1.30 times those in the native plant soils.The TN and NO_(3)^(-)contents in the rhizosphere soil of B.pilosa were 1.30 to 2.71 times those in the native plant soils.The activities of acid phosphatase,alkaline phosphatase,and urease in the rhizosphere soil of B.pilosa were 1.98-2.25 times higher than in the native plant soils.Using high-throughput sequencing of the16S rRNA gene,we found that B.pilosa altered the composition of the soil microbial community.Specifically,many genera in Actinobacteria and Proteobacteria were enriched in B.pilosa soils.Further correlation analyses verified that these genera had significantly positive relationships with soil nutrients and enzyme activities.Plant biomass,soil p H,and the contents of organic matter,TN,NO_(3)^(-),TP,AP,TK,and AK were the main factors affecting soil microbial communities.This study showed that the invasion of B.pilosa led to significant alterations in the composition of the soil microbial communities.These changes were closely linked to modifications in plant traits as well as soil physical and chemical properties.Some microbial species related to C,N and P cycling were enriched in the soil invaded by B.pilosa.These findings provide additional support for the hypothesis of soil-microbe feedback in the successful invasion of alien plants.They also offer insights into the ecological mechanism by which soil microbes contribute to the successful invasion of B.pilosa.Overall,our research contributes to a better understanding of the complex interactions between invasive plants,soil microbial communities,and ecosystem dynamics.
基金supported by the Science and Technology Planning Project of Gansu Province,China(23ZDKA017).
文摘In the Loess Plateau of China,land-use pattern is a major factor in controlling underlying biological processes.Additionally,the process of land-use pattern was accompanied by abandoned lands,potentially impacting soil microbe.However,limited researches were conducted to study the impacts of land-use patterns on the diversity and community of soil microorganisms in this area.The study aimed to investigate soil microbial community diversity and composition using high-throughput deoxyribonucleic acid(DNA)sequencing under different land-use patterns(apricot tree land,apple tree land,peach tree land,corn land,and abandoned land).The results showed a substantial difference(P<0.050)in bacterial alpha-diversity and beta-diversity between abandoned land and other land-use patterns,with the exception of Shannon index.While fungal beta-diversity was not considerably impacted by land-use patterns,fungal alpha-diversity indices varied significantly.The relative abundance of Actinobacteriota(34.90%),Proteobacteria(20.65%),and Ascomycota(77.42%)varied in soils with different land-use patterns.Soil pH exerted a dominant impact on the soil bacterial communities'composition,whereas soil available phosphorus was the main factor shaping the soil fungal communities'composition.These findings suggest that variations in land-use pattern had resulted in changes to soil properties,subsequently impacting diversity and structure of microbial community in the Loess Plateau.Given the strong interdependence between soil and its microbiota,it is imperative to reclaim abandoned lands to maintain soil fertility and sustain its function,which will have significant ecological service implications,particularly with regards to soil conservation in ecologically vulnerable areas.
基金The authors are grateful for the financial support from National Natural Science Foundation of China(32001728).
文摘Free amino acid(FAA)is the important component of vinegar that infl uences quality perception and consumer acceptance.FAA is one of the major metabolites produced by microorganisms;however,the microbial metabolic network on FAA biosynthesis remains unclear.Through metagenomic analysis,this work aimed to elucidate the roles of microbes in FAA biosynthesis during Monascus rice vinegar fermentation.Taxonomic profiles from functional analyses showed 14 dominant genera with high contributions to the metabolism pathways.The metabolic network for FAA biosynthesis was then constructed,and the microbial distribution in different metabolic pathways was illuminated.The results revealed that 5 functional genera were closely involved in FAA biosynthesis.This study illuminated the metabolic roles of microorganisms in FAA biosynthesis and provided crucial insights into the functional attributes of microbiota in vinegar fermentation.
文摘Lipocalin 2(LCN2)plays a pivotal role in iron metabolism,particularly in the context of microbial infection resistance(e.g.,viruses,bacteria,parasites,etc.).LCN2 combats microbial infection by directly assisting the body in competing with microorganisms for iron,inducing immune cells to secrete various cytokines to enhance systemic immune responses,or recruiting neutrophils to infectious sites.The liver serves as the primary organ for LCN2 secretion during microbial infections.This review encapsulates recent advances in dynamic changes,clinical values,and the effects of LCN2 in infectious liver diseases caused by various microbial microorganisms.
文摘Objective: The main objective of this study was to assess the degree of contamination of surface waters by heavy metals and pesticides. Method: To this end, data were collected in December 2022 from four specific sampling stations: Okpara, Térou, Affon and Adjiro. Levels of heavy metals, including cadmium, chromium, copper, iron, mercury, nickel and lead, were measured and subjected to in-depth statistical analysis using graphical summation models. In addition, the concentrations of pesticide active ingredients present in the samples were interpreted and evaluated. The statistical data collected during this study were processed using R software, version 3.5.0. Results: The values obtained at the different stations Okpara, Térou, Affon and Adjiro are respectively Arsenic (2 × 10<sup>-4</sup> mg/L;2.2 × 10<sup>-1</sup> mg/L;1.2 × 10<sup>-4</sup> mg/L;2 × 10<sup>-4</sup> mg/L), Cadmium (4.4 × 10<sup>-5</sup> mg/L;1.1 × 10<sup>-2</sup> mg/L;10<sup>-4</sup> mg/L;4 × 10<sup>-4</sup> mg/L). Then Copper (7 × 10<sup>-4</sup> mg/L;3 × 10<sup>-3</sup> mg/L;7 × 10<sup>-4</sup> mg/L;1 × 10<sup>-4</sup> mg/L), Iron (1.51 mg/L;6.4 × 10<sup>-1</sup> mg/L;2.0012 mg/L;2.9 × 10<sup>-1</sup> mg/L), Lead (0 mg/L;0 mg/L;1.5 × 10<sup>-3</sup> mg/L;1.5 × 10<sup>-3</sup> mg/L). Mercury, nickel and chromium were not detected in surface waters. It is important to note that the values obtained for trace metals (Cadmium, Chromium, Copper, Iron, Mercury, nickel and chromium were not detected in surface waters. It is important to note that the values obtained for trace metals (cadmium, chromium, copper, iron, mercury, nickel and lead) were all below the guideline standards set by the WHO in 2006 for uncontaminated surface waters. This indicates that the surface waters of the Upper Ouémé were below acceptable contamination thresholds in terms of heavy metals. However, the presence of pesticide active ingredients such as cyfluthrin, endosulfan-alpha, endosulfan-beta, profenosfos, tihan, atrazine, gala super and glycel clearly indicates that these surface waters are subject to agricultural contamination.
文摘Background:It is possible that preservative-free eye drops can be contaminated.The aim of this study was to assess the incidence of microbial contamination of preservative-free hospital-prepared anti-infective eye drops and investigate factors that contribute to contamination.This finding may help to raise awareness of this problem to medical healthcare staff and patients in order to prevent the transmission of microorganisms from eye drops to the patients through treatment of pre-existing eye diseases.Methods:Two hundred and ninety-five eye drop bottles were collected from patients attending Rajavithi Hospital Ophthalmologic outpatient and inpatient department,including both those used by patients at home and those administered in the hospital by medical staff.Samples were taken from the tips of droppers and bottles,and the residual fluid inside the bottles was then cultivated onto different culture plates.The culture results were identified and analyzed according to various factors related to both individual users and the bottles.Results:Seven different types of eye drops were collected and 71(24.06%)of the 295 bottles were contaminated.Vancomycin eye drops were the most contaminated.Twenty-six different types of pathogens were identified,most frequently mold(42.98%),and the amount of contamination was higher in tips than in residual fluid inside the bottle.There was no statistically significant difference in contamination between patients used eye drops collected in outpatient units(32.14%)and medical staff used eye drops collected in inpatient settings(23.22%).The only factor that was statistically significant was the number of eye drops used per person.We found that samples from patients who used only up to 2 eye drops suffered contamination(42.8%)more than those from their counterparts who used at least 3(22.18%),P¼0.02.Conclusions:Of these preservative-free hospital preparations anti-infective eye drops,24.06%were contaminated.The number of eye drops used per person was statistically significant in triggering contamination.There is a possibility of number of eyedrops use person may trigger contamination.
基金supported by the National Key Research and Development Program of China (2018YFC1604304)the National Risk Surveillance Fund in Chinathe National Natural Science Foundation of China (No.81773481).
文摘This study investigated the microbial contamination of ice cream in China.A total of 2887 ice cream samples were collected from different regions of China.Contamination by the aerobic plate count(APC),coliforms,and three foodborne pathogens,Listeria monocytogenes(L.monocytogenes),Staphylococcus aureus(S.aureus),and Salmonella spp.,was detected in the samples.L.monocytogenes isolates were further analyzed for antibiotic susceptibility and multi-locus sequence typing(MLST).The results showed that APC was more than 10^(5) colony forming units(CFU)/g in 6.10%(176/2887)and coliform was more than 10^(2) CFU/g in 15.69%(453/2887)of all samples.The positive rates of S.aureus,L.monocytogenes,and Salmonella spp.were 0.66%,0.62%,and 0.10%,respectively.Among these,S.aureus contamination was more than 102 CFU/g in two samples,and L.monocytogenes in the positive sample was in the range of 0.3-240 most probable number(MPN)/g.with a median of 4.3 MPN/g.The hygienic status of the packaged samples was much better than that of the bulk samples(P<0.05).Catering samples were more frequently and heavily contaminated than samples from retail and wholesale outlets(P<0.05).No significant differences were observed in samples bought from urban and rural areas(P>0.05).For 18 L.monocytogenes strains isolated from ice cream,the resistance rate of nine antibiotics was 5.56%(1/18).By MLST,the L.monocytogenes strains were classified into nine sequence types(STs),of which ST8 was the most common(six isolates).These results indicate that a potential health risk to the public may be caused by ice cream,particularly in susceptiblepopulations.
