Pathogenic microorganisms produce numerous metabolites,including volatile organic compounds(VOCs).Monitoring these metabolites in biological matrices(e.g.,urine,blood,or breath)can reveal the presence of specific micr...Pathogenic microorganisms produce numerous metabolites,including volatile organic compounds(VOCs).Monitoring these metabolites in biological matrices(e.g.,urine,blood,or breath)can reveal the presence of specific microorganisms,enabling the early diagnosis of infections and the timely implementation of tar-geted therapy.However,complex matrices only contain trace levels of VOCs,and their constituent com-ponents can hinder determination of these compounds.Therefore,modern analytical techniques enabling the non-invasive identification and precise quantification of microbial VOCs are needed.In this paper,we discuss bacterial VOC analysis under in vitro conditions,in animal models and disease diagnosis in humans,including techniques for offline and online analysis in clinical settings.We also consider the advantages and limitations of novel microextraction techniques used to prepare biological samples for VOC analysis,in addition to reviewing current clinical studies on bacterial volatilomes that address inter-species in-teractions,the kinetics of VOC metabolism,and species-and drug-resistance specificity.展开更多
AIM:To investigate the types of bacteria in patients with eye infections in Suzhou and their drug resistance to commonly used antibacterial drugs.METHODS:The clinical data of 155 patients were retrospectively collecte...AIM:To investigate the types of bacteria in patients with eye infections in Suzhou and their drug resistance to commonly used antibacterial drugs.METHODS:The clinical data of 155 patients were retrospectively collected in this study,and the pathogenic bacteria species and drug resistance of each pathogenic bacteria were analyzed.RESULTS:Among the 155 patients(age from 12 to 87 years old,with an average age of 57,99 males and 56 females)with eye infections(160 eyes:74 in the left eye,76 in the right eye and 5 in both eyes,all of which were exogenous),71(45.81%)strains were gram-positive bacteria,23(14.84%)strains were gram-negative bacteria and 61(39.35%)strains were fungi.Gram-positive bacteria were highly resistant to penicillin and erythromycin(78.87%and 46.48%respectively),but least resistant to vancomycin at 0.Gram-negative bacteria were highly resistant to cefoxitin and compound sulfamethoxazole(100%and 95.65%respectively),but least resistant to meropenem at 0.Comparison of the resistance of gram-positive and gram-negative bacteria to some drugs revealed statistically significant differences(P<0.05)in the resistance of both to cefoxitin,cotrimoxazole,levofloxacin,cefuroxime,ceftriaxone and ceftazidime,and both had higher rates of resistance to gram-negative bacteria than to gram-positive bacteria.The distribution of bacterial infection strains showed that Staphylococcus epidermidis was the most common strain in the conjunctiva,cornea,aqueous humor or vitreous body and other eye parts.Besides,Fusarium and Pseudomonas aeruginosa were also among the most common strains of conjunctival and corneal infections.CONCLUSION:Gram-positive bacteria are the dominant bacteria in eye infections,followed by gram-negative bacteria and fungi.Considering the resistance of gramnegative bacteria to multiple drugs,monitoring of bacteria should be strengthened in eye bacterial infections for effective prevention and control to reduce complications caused by eye infections.展开更多
The aim of our study was to use a biosurfactant produced by Bacillus and Lactobacillus isolates as an antiseptic in the formulation of local soap. A total of 60 isolates were characterized by microbiological technique...The aim of our study was to use a biosurfactant produced by Bacillus and Lactobacillus isolates as an antiseptic in the formulation of local soap. A total of 60 isolates were characterized by microbiological techniques (30 Bacillus and 30 Lactobacillus) and the ability to produce biosurfactants was demonstrated by a hydrocarbon emulsification index (E24). The emulsification indexes (E24) varied from 9% to 100% for Bacillus and from 33% to 100% for Lactobacillus as well. The antagonistic assay showed that biosurfactants were able to inhibit the formation of biofilms and growth of pathogens such as Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus cereus, Salmonella typhirium, Shigella boydii and Proteus mirabilis. The biosurfactant consortium (BioC) from Bacillus consortium and from Lactobacillus was able to inhibit biofilm formation and the pathogens growth. The BioC was stable to alkaline pH and the temperatures stability of Biosurfactant was ranging from 50°C to 90°C. The soap was made by the cold saponification process using one biosurfactant consortium formulated. This soap has a pH of 10 and showed good cleaning power and good foam stability. Similarly, the soap showed good antiseptic power and disinfection power against all pathogens tested. Handwashing is critical to preventing disease transmission. The persistence of pathogens in waste water was evaluated. The BioS produced showed good disinfection power against all pathogens tested. The valor of reduction on the hands and in the waste water was significantly more than compared to the control soaps used. This soap could be used in the prevention, fighting, and treatment of bacterial and viral infections.展开更多
According to the theory of Chinese veterinary medicine and characteristics of Chinese herbal medicine, four different preparations of compound Chinese medicine ＂Zengrujianniusan＂ were composed, and the prepared wate...According to the theory of Chinese veterinary medicine and characteristics of Chinese herbal medicine, four different preparations of compound Chinese medicine ＂Zengrujianniusan＂ were composed, and the prepared water decoction was used to carry on the bacteriostatic test on main pathogens of cow recessiveness mastitis. The results showed that the four different prescriptions of water decoction all had antibacterial effects. The prescription 3 was sensitive to Staphylococcus aureus and Streptococcus agalactiae, while the other three prescriptions showed high sensitivity, and the prescription 3 had the strongest bacteriostatic effects.展开更多
The objective of this study is to determine and compare the heavy metal（Zn,Cu,Cd,Pb） and bacterial（E.coli,coliform and Salmonella spp.） contamination between swine farms utilizing biogas and non-biogas systems in ...The objective of this study is to determine and compare the heavy metal（Zn,Cu,Cd,Pb） and bacterial（E.coli,coliform and Salmonella spp.） contamination between swine farms utilizing biogas and non-biogas systems in the central part of Thailand.Results showed that average levels of E.coli,coliform,BOD,COD,Zn,Cu and Pb in sludge from the post-biogas pond were higher than the standard limits.Moreover,the levels of E.coli,coliform,Cd and Pb were also higher than the standard limits for dry manure.The levels of E.coli,coliform and BOD on biogas farms were lower than on non-biogas farms.Following isolation of Salmonella spp.,it was found that Salmonella serovars Rissen was the most abundant at 18.46%（12/65）,followed by Anatum 12.31%（8/65）,and Kedougou 9.23%（6/65）.The pathogenic strains of Salmonella serovars Paratyphi B var.java and Typhimurium were present in equal amounts at 4.62%（3/65） in samples from all swine farms.This study revealed that significant reduction in E.coli and coliform levels in sludge from covered lagoon biogas systems on swine farms.The presence of Salmonella as well as Cd and Pb,in significant amount in dry manure,suggests that there is a high probability of environmental contamination if it is used for agricultural purposes.Thus,careful waste and manure disposal from swine farms and the regular monitoring of wastewater is strongly recommended to ensure the safety of humans,other animals and the environment.展开更多
Application of compost in agricultural practice could potentially cause contamination of foodstuffs with pathogenic bacteria such as Escherichia coli O157：H7 （E. Coli O157）. We investigated pathogenic bacteria in c...Application of compost in agricultural practice could potentially cause contamination of foodstuffs with pathogenic bacteria such as Escherichia coli O157：H7 （E. Coli O157）. We investigated pathogenic bacteria in compost collected from the compost facilities, and evaluated the survival of E. coli K12 and O157 in laboratory experiments. Out of 19 compost product samples, coliform bacteria and salmonella were detected in 7 and 3 samples respectively. The number of coliform bacteria was 1.8 × 10^2 to 2.5 × 10^6 CFU/g dw and that of salmonella was 4.2 × 10^1 to 6.0 × 10^3 CFU/g dw. Moreover. coliform bacteria, fecal coliform, E. coli and salmonella were detected during composting at 54℃ to 67℃. The results indicated that moisture content was a very important factor to the heat sensitivity of pathogenic bacteria in compost, E. coli in compost of high moisture content was more sensitive than that in compost of low moisture content, cells harvested in logarithmic phase was more sensitive than these in stationary phase, and E. coli K12 was more sensitive than E. coli O157. Based on the D values, the lethal time of E. coli K12 and 0157 from 10^8 to 10^0 CFU/g dw were 16.3 and 28.8 min, respectively, at 60℃ in compost with 40% moisture content. However, some E. coli cells survived in composting process at 54℃ to 67℃. Water potential（low moisture content） and physiological aspects of bacteria（stationary phase） could explain only in part of the prolonged survival of E. coli in compost, and there should be some other factors that are conducive to bacterial survial in compost.展开更多
Pharmaceutical wastewater treatment plants（WWTPs） are thought to be a ＂seedbed＂ and reservoirs for multi-antibiotic resistant pathogenic bacteria which can be transmitted to the air environment through aeration. W...Pharmaceutical wastewater treatment plants（WWTPs） are thought to be a ＂seedbed＂ and reservoirs for multi-antibiotic resistant pathogenic bacteria which can be transmitted to the air environment through aeration. We quantified airborne multi-antibiotic resistance in a full-scale plant to treat antibiotics-producing wastewater by collecting bioaerosol samples from December2014 to July 2015. Gram-negative opportunistic pathogenic bacteria（GNOPB） were isolated, and antibiotic susceptibility tests against 18 commonly used antibiotics, including 11 β-lactam antibiotics, 3 aminoglycosides, 2 fluoroquinolones, 1 furan and 1 sulfonamide, were conducted.More than 45% of airborne bacteria isolated from the pharmaceutical WWTP were resistant to three or more antibiotics, and some opportunistic pathogenic strains were resistant to 16 antibiotics, whereas 45.3% and 50.3% of the strains isolated from residential community and municipal WWTP showed resistance to three or more antibiotics. The calculation of the multiple antibiotic resistance（MAR） index demonstrated that the air environment in the pharmaceutical WWTP was highly impacted by antibiotic resistance, while the residential community and municipal WWTP was less impacted by antibiotic resistance. In addition, we determined that the dominant genera of opportunistic pathogenic bacteria isolated from all bioaerosol samples were Acinetobacter, Alcaligenes, Citrobacter, Enterobacter, Escherichia, Klebsiella, Pantoea, Pseudomonas and Sphingomonas. Collectively, these results indicate the proliferations and spread of antibiotic resistance through bioaerosols in WWTP treating cephalosporin-producing wastewater, which imposed a potential health risk for the staff and residents in the neighborhood, calling for administrative measures to minimize the air-transmission hazard.展开更多
Pathogenic bacteria pose a global threat to public health and attract considerable attention in terms of food safety.Rapid and highly sensitive strategies for detecting pathogenic bacteria must be urgently developed t...Pathogenic bacteria pose a global threat to public health and attract considerable attention in terms of food safety.Rapid and highly sensitive strategies for detecting pathogenic bacteria must be urgently developed to ensure food safety and public health.Microchips offer significant advantages for pathogenic bacterial detection in terms of speed and sensitivity compared with those of traditional techniques.Microfluidic devices,in particular,have attracted significant attention for the detection of pathogenic bacteria owing to their ease of operation,high throughput,cost-effectiveness,and high sensitivity.This review summarizes representative articles on the analysis of pathogenic bacteria using microchip-based systems.A detailed and comprehensive overview of microchip-based techniques for the detection of pathogenic bacteria is presented herein,and their advantages and disadvantages are discussed to compare their applications.The accomplishments and shortcomings of these microchips have been highlighted,and the direction of development and prospects of the analysis of pathogenic bacteria have been examined.The content of this review is anticipated to provide constructive suggestions for further development of highly effective and advanced microchip-based strategies for detecting pathogenic bacteria.展开更多
Rapid on-site detection of pathogenic bacteria with high sensitivity and specificity is becoming an urgent need in public health assurance, medical diagnostics, environmental monitoring, and food safety fields. Despit...Rapid on-site detection of pathogenic bacteria with high sensitivity and specificity is becoming an urgent need in public health assurance, medical diagnostics, environmental monitoring, and food safety fields. Despite being reliable and widely used, the existing methods of bacteria detection are cumbersome and time-consuming, which is not conducive to field detection. Microfluidic lab-on-a-chip technology has provided a detective tool for various analytes, due to its miniaturization, portability and low reagent consumption. Within this progress report, advances in the bacteria detection using microfluidic biosensors were discussed. Typical methods for pathogenic bacteria capture, separation and detection were introduced respectively in the first part. Then key applications of microfluidic biosensor-based rapid bacteria detection were presented. Finally, we made a conclusion and discussed possible research prospects in aspects of microfluidic biosensors for rapid detection of pathogenic bacteria.展开更多
Edwardsiellosis of flounder and turbot occurring in different mariculture farms during 2001～ 2004 was examined, including the conditions of disease occurrence, clinical signs and pathological changes. The results sho...Edwardsiellosis of flounder and turbot occurring in different mariculture farms during 2001～ 2004 was examined, including the conditions of disease occurrence, clinical signs and pathological changes. The results showed that all diseased fishes expressed bacterial septicaemia. A total of 148 strains were identified using a combination of traditional physiological and biochemical tests and partial 16S rRNA gene analysis. In addition, the mole fraction G ＋ C ratio of the DNA of representative strain of isolates and serum homology were detected, and pathogenicity tests of isolates were conducted by experimental infection. The results revealed that 148 strains were identified as E. tarda of genus Edwardsiella, all the isolates are of serologic similarity, and have strong pathogenicity to flounder and turbot.展开更多
Objective： To understand distribution and drug resistance of pathogenic bacteria from a specialized cancer hospital in 2013 in order to provide a basis for rational clinical antimicrobial agents. Methods： Pathogenic...Objective： To understand distribution and drug resistance of pathogenic bacteria from a specialized cancer hospital in 2013 in order to provide a basis for rational clinical antimicrobial agents. Methods： Pathogenic bacteria identification and drug sensitivity tests were performed with a VITEK 2 compact automatic identification system and data were analyzed using WHONET5.6 software.Results： Of the 1,378 strains tested, 980 were Gram-negative bacilli, accounting for 71.1%, in which Klebsiella pneumonia, Escherichia coli and Pseudomonas aeruginosa were the dominant strains. We found 328 Gram-positive coccus, accounting for 23.8%, in which the amount of Staphylococcus aureus was the highest. We identified 46 fungi, accounting for 4.1%. According to the departmental distribution within the hospital, the surgical departments isolated the major strains, accounting for 49.7%. According to disease types, lung cancer, intestinal cancer and esophagus cancer were the top three, accounting for 20.9%, 17.3% and 14.2%, respectively. No strains were resistant to imipenem, ertapenem or vancomycin.Conclusions： Pathogenic bacteria isolated from the specialized cancer hospital have different resistance rates compared to commonly used antimicrobial agents; therefore antimicrobial agents to reduce the morbidity and mortality of infections should be used.展开更多
The harm of pathogenic bacteria to humans has promoted extensive research on physiological processes of pathogens,such as the mechanism of bacterial infection,antibiotic mode of action,and bacterial antimicrobial resi...The harm of pathogenic bacteria to humans has promoted extensive research on physiological processes of pathogens,such as the mechanism of bacterial infection,antibiotic mode of action,and bacterial antimicrobial resistance.Most of these processes can be better investigated by timely tracking of fluorophore-derived antibiotics in living cells.In this paper,we will review the recent development of fluorescent antibiotics featuring the conjugation with various fluorophores,and focus on their applications in fluorescent imaging and real-time detection for various physiological processes of bacteria in vivo.展开更多
Phenazines are secondary metabolites with broad spectrum antibiotic activity and thus show high potential in biological control of pathogens. In this study, we identified phenazine biosynthesis （phz） genes in two ge...Phenazines are secondary metabolites with broad spectrum antibiotic activity and thus show high potential in biological control of pathogens. In this study, we identified phenazine biosynthesis （phz） genes in two genome-completed plant pathogenic bacteria Pseudomonas syringae pv. tomato （Pst） DC3000 and Xanthomonas oryzae pv. oryzae （Xoo） PXO99A. Unlike the phz genes in typical phenazine-producing pseudomonads, phz homologs in Pst DC3000 and Xoo PXO99A consisted of phzC/D/E/F/G and phzC/E1/E2/F/G, respectively, and the both were not organized into an operon. Detection experiments demonstrated that phenazine-l-carboxylic acid （PCA） of Pst DC3000 accumulated to 13.4 IJg L-1, while that of Xoo PXO99A was almost undetectable. Moreover, Pst DC3000 was resistant to 1 mg mL-1 PCA, while Xoo PXO99A was sensitive to 50 IJg mL ~ PCA. Furthermore, mutation of phzF blocked the PCA production and significantly reduced the pathogenicity of Pst DC3000 in tomato, while the complementary strains restored these phenotypes. These results revealed that Pst DC3000 produces low level of and is resistant to phenazines and thus is unable to be biologically controlled by phenazines. Additionally, phz-mediated PCA production is required for full pathogenicity of Pst DC3000. To our knowledge, this is the first report of PCA production and its function in pathogenicity of a plant pathogenic P. syringae strain.展开更多
In recent years, researchers tended to bring new alternative to biological protective systems used in conservation of food and production of safe food. Use of bacteriophage against to pathogen bacteria in food was the...In recent years, researchers tended to bring new alternative to biological protective systems used in conservation of food and production of safe food. Use of bacteriophage against to pathogen bacteria in food was the most hopeful system in these methods about bio-control. Controls of bacteriophage for each pathogen species and subspecies and determination of phage-host originality are important because efficient bio-control was achieved. Researches concentrated on some food-borne pathogen bacteria such as E. coli O157：H7, Campylobacter, Salmonella and Listeria. In a consequence of these studies made as in vitro and in vivo, first commercial production of phage which will be used in foods was made in Netherlands. Also, it has been informed that use of phage is cost-efficient alternative as compared with other preservatives. This review, discussed application of bacteriophages as bio-control agents in food and advantages and disadvantages about uses of bacteriophages by taking into account antimicrobial characteristics of them.展开更多
Antibiotic resistant bacteria pass between humans, between animals and between humans and animals in both directions, the use of antibiotics in poultry has contributed to multiple antibiotic resistant in pathogenic ba...Antibiotic resistant bacteria pass between humans, between animals and between humans and animals in both directions, the use of antibiotics in poultry has contributed to multiple antibiotic resistant in pathogenic bacteria and use of two antibiotics might prevent the emergence of resistance to either. In this study, synergistic effect of combined antibiotics against multidrug resistant human pathogenic bacterial isolates from poultry droppings in Akure, Nigeria was examined. Collection of samples, isolation and identification of bacteria were carried out using standard microbiological method, antibiotic sensitivity test was performed by disc diffusion method and zone of inhibition was used to interpret the sensitivity test as resistant, susceptible or intermediate while combined effects of two antibiotics were investigated by macrobroth dilution and checkerboard assay methods while the synergetic effects of combined antibiotics were calculated using Fractional Inhibitory Concentration (FIC) and percentage synergistic interaction was calculated. All the ten (10) species of bacterial isolates were multidrug resistant and are less resistant to ofloxacin. The highest percentage synergistic interactions observed were Ofloxacin + Amoxicillin (90%), Ciprofloxacin + Amoxicillin (90%), Tetracycline + Amoxicillin (70%), Tetracycline + Augmentin (80%), Cotrimoxazol + Amoxicillin (50%), Cotrimoxazol + Augmentin (70%), Chloramphenicol + Amoxicillin (70%) and Chloramphenicol + Augmentin (80%). Poultry droppings is a potential source of human pathogenic bacteria, high frequency of multiple antibiotic resistance bacteria observed in this study is of great treat to man as this may cause the treatment of infection caused by these bacteria to be difficult. Combination of beta-lactam antibiotic with fluoroqunolones, tetracycline, Chloramphenicol and Cotrimoxazole was synergetic and this will reduce dose related toxicity and prevent resistance to single antibiotic.展开更多
Objective:To understand the pathogenic bacteria isolated from patients and their drug resistance changes in general ICU of the Affiliated Hospital of Hebei University,so as to provide reference for appropriate selecti...Objective:To understand the pathogenic bacteria isolated from patients and their drug resistance changes in general ICU of the Affiliated Hospital of Hebei University,so as to provide reference for appropriate selection of antibiotics in clinical practice.Methods:A retrospective investigation was conducted to analyze the bacteriological distribution and drug resistance of nosocomial pathogens isolated from the specimens of hospitalized patients in the comprehensive ICU of the hospital from 2019 to 2021.The US technology BD Phoenix 100 automatic bacterial identification analyzer was used for bacterial identification of the pathogen samples,disk diffusion method was used for drug susceptibility test,and SPSS 22.0 software was used to analyze the trend of drug resistance.Results:A total of 970 strains of nosocomial pathogens were detected in the three years.The main pathogens were Acinetobacter baumannii(133 strains,13.71%),Klebsiella pneumoniae(106 strains,10.93%),Pseudomonas aeruginosa(83 strains,8.56%),Escherichia coli(76 strains,7.84%)and Enterococcus faecium(69 strains,7.11%).The resistance rate of Acinetobacter baumannii to antibiotics was high.Klebsiella pneumoniae,Pseudomonas aeruginosa and Escherichia coli had low resistance rates to carbapenems.The situation of bacterial drug resistance is still serious.Conclusion:The drug resistance of pathogenic bacteria collected from Class III Grade A Hospital’s patients to antibiotics was generally high.Therefore,clinical departments should strengthen the inspection of specimens of infection and drug sensitivity test in order to grasp the resistance mechanisms and drug resistance of pathogenic bacteria changes,and select appropriate antimicrobial agents according to the test results.Besides,the formation of drug-resistant strains also needs to be prevented,and the treatment of patients with severe infection needs to be improved.展开更多
Two-dimensional(2D)nanomaterials have captured an increasing attention in biophotonics owing to their excellent optical features.Herein,2D hafnium ditelluride(HfTe_(2)),a new member of transition metal tellurides,is e...Two-dimensional(2D)nanomaterials have captured an increasing attention in biophotonics owing to their excellent optical features.Herein,2D hafnium ditelluride(HfTe_(2)),a new member of transition metal tellurides,is exploited to support gold nanoparticles fabricating HfTe_(2)-Au nanocomposites.The nanohybrids can serve as novel 2D surface-enhanced Raman scattering(SERS)substrate for the label-free detection of analyte with high sensitivity and reproducibility.Chemical mechanism originated from HfTe_(2) nanosheets and the electromagnetic enhancement induced by the hot spots on the nano-hybrids may largely contribute to the superior SERS effect of HfTe_(2)-Au nanocomposites.Finally,HfTe_(2)-Au nanocomposites are utilized for the label-free SERS analysis of foodborne pathogenic bac-teria,which realize the rapid and ultrasensitive Raman test of Escherichia coli,Listeria mono-cytogenes,Staphylococcus aureus and Salmonella with the limit of detection of 10 CFU/mL and the maximum Raman enhancement factor up to 1.7×10^(8).Combined with principal component analysis,HfTe_(2)-Au-based SERS analysis also completes the bacterial classification without extra treatment.展开更多
Objective:To assess the antibacterial activity of 5 selected plants against 4 pathogenic bacteria.Methods:Three solvents with different polarities were used to extract antimicrobial agents from the plants via macerati...Objective:To assess the antibacterial activity of 5 selected plants against 4 pathogenic bacteria.Methods:Three solvents with different polarities were used to extract antimicrobial agents from the plants via maceration technique.The agar-disc diffusion technique was adopted to primarily screen antibacterial activities.Broth-dilution assay was employed to determine the minimum inhibitory concentration(MIC)and the minimum bactericidal concentration(MBC).Results:Among all extracts,the ethanol extract of Piper betle Linn showed the highest antibacterial activity against Gram-positive and the negative bacteria.MIC and MBC of the ethanol extract of Piper betle Linn against Salmonella typhimurium were the same(1?562.50 mg/L);while it showed the highest MIC and MBC against Pseudomonas aeruginosa of 6?250 mg/L and 12?500 mg/L,respectively.Conclusions:Salmonella typhimurium is the most susceptible bacteria while Pseudomonas aeruginosa is the most resistant bacteria towards the ethanol extract of Piper betle Linn.Piper betle possesses compounds with potential antibacterial activity and might be useful as an alternative to control infectious diseases.展开更多
In this research,36 cows with clinical mastitis were treated with the Chinese herb injection Ruyuankang which was developed by our group.Milk samples of pre and post treatment of Ruyuankang were collected for isolatio...In this research,36 cows with clinical mastitis were treated with the Chinese herb injection Ruyuankang which was developed by our group.Milk samples of pre and post treatment of Ruyuankang were collected for isolation and characterization of pathogenic bacteria.The dynamic changes of pathogenic bacteria were investigated as well.The results indicated that Ruyuankang could effectively inhibit the common pathogenic bacteria of mastitis which result in the negative rate of pathogenic bacteria 71.74%.展开更多
<strong>Background</strong>: Mealie Meal is one of the by-products of maize from dry milling. It constitutes more significant part of the daily diet of growing population of the Lusaka District of Zambia. ...<strong>Background</strong>: Mealie Meal is one of the by-products of maize from dry milling. It constitutes more significant part of the daily diet of growing population of the Lusaka District of Zambia. However, reported cases of a cholera outbreak in October 2017-May 2018 were attributed to water contamination in the households of Lusaka. Hitherto there is no previous study or documented data for gastroenteritis caused by microbial contamination from food stores. <strong>Aim</strong>: The main objective of the study was to carry out species identification of Mealie meal spoilage organisms and pathogenic bacteria from selected food stores in Lusaka district from September 2019-March 2020. Crosssectional survey was conducted for food spoilage organisms and pathogenic bacteria of packaged maize meal flour from a selected food store. The number of packaged Mealie meal samples from selected food stores included in the study was 143 samples. Samples were obtained by a simple stratified random selection from food stores in Lusaka District. Thus Mealie Meal samples bought from Street food vendors were 96 (67%), Shops—30 (21%), Malls—17 (11.9%). Subsequently isolation by spread and pour plate methods, and species identification of microbial contamination by Cell Culture processes coupled to microbial morphological and biochemical characterization was performed. Microsoft Office Excel (version 2007) Spreadsheet was employed for the categorical data analysis and summarized graphical presentation of data. Laboratory findings revealed: Spoilage organisms—<em>Aspergillum</em> species, <em>Mucor</em> Species, <em>Candida</em> Species, <em>Clostridium</em> Species and <em>Bacillus</em> Species;Pathogenic Bacteria Species—<em>Clostridium perfringens</em>, <em>Staphylococcus aureus</em>, <em>Clostridium tetani</em>, <em>Bacillus</em>, <em>Escherichia coli</em>, <em>Pseudomonas aeruginosa</em> and <em>Yesinia pestis</em>. It can be established from the laboratory results earlier mentioned that the food poisoning outbreak could evolve from food stores in Lusaka district apart from water contamination.展开更多
基金funded by the National Science Centre,Poland(Project No.:2017/26/D/NZ6/00136).
文摘Pathogenic microorganisms produce numerous metabolites,including volatile organic compounds(VOCs).Monitoring these metabolites in biological matrices(e.g.,urine,blood,or breath)can reveal the presence of specific microorganisms,enabling the early diagnosis of infections and the timely implementation of tar-geted therapy.However,complex matrices only contain trace levels of VOCs,and their constituent com-ponents can hinder determination of these compounds.Therefore,modern analytical techniques enabling the non-invasive identification and precise quantification of microbial VOCs are needed.In this paper,we discuss bacterial VOC analysis under in vitro conditions,in animal models and disease diagnosis in humans,including techniques for offline and online analysis in clinical settings.We also consider the advantages and limitations of novel microextraction techniques used to prepare biological samples for VOC analysis,in addition to reviewing current clinical studies on bacterial volatilomes that address inter-species in-teractions,the kinetics of VOC metabolism,and species-and drug-resistance specificity.
文摘AIM:To investigate the types of bacteria in patients with eye infections in Suzhou and their drug resistance to commonly used antibacterial drugs.METHODS:The clinical data of 155 patients were retrospectively collected in this study,and the pathogenic bacteria species and drug resistance of each pathogenic bacteria were analyzed.RESULTS:Among the 155 patients(age from 12 to 87 years old,with an average age of 57,99 males and 56 females)with eye infections(160 eyes:74 in the left eye,76 in the right eye and 5 in both eyes,all of which were exogenous),71(45.81%)strains were gram-positive bacteria,23(14.84%)strains were gram-negative bacteria and 61(39.35%)strains were fungi.Gram-positive bacteria were highly resistant to penicillin and erythromycin(78.87%and 46.48%respectively),but least resistant to vancomycin at 0.Gram-negative bacteria were highly resistant to cefoxitin and compound sulfamethoxazole(100%and 95.65%respectively),but least resistant to meropenem at 0.Comparison of the resistance of gram-positive and gram-negative bacteria to some drugs revealed statistically significant differences(P<0.05)in the resistance of both to cefoxitin,cotrimoxazole,levofloxacin,cefuroxime,ceftriaxone and ceftazidime,and both had higher rates of resistance to gram-negative bacteria than to gram-positive bacteria.The distribution of bacterial infection strains showed that Staphylococcus epidermidis was the most common strain in the conjunctiva,cornea,aqueous humor or vitreous body and other eye parts.Besides,Fusarium and Pseudomonas aeruginosa were also among the most common strains of conjunctival and corneal infections.CONCLUSION:Gram-positive bacteria are the dominant bacteria in eye infections,followed by gram-negative bacteria and fungi.Considering the resistance of gramnegative bacteria to multiple drugs,monitoring of bacteria should be strengthened in eye bacterial infections for effective prevention and control to reduce complications caused by eye infections.
文摘The aim of our study was to use a biosurfactant produced by Bacillus and Lactobacillus isolates as an antiseptic in the formulation of local soap. A total of 60 isolates were characterized by microbiological techniques (30 Bacillus and 30 Lactobacillus) and the ability to produce biosurfactants was demonstrated by a hydrocarbon emulsification index (E24). The emulsification indexes (E24) varied from 9% to 100% for Bacillus and from 33% to 100% for Lactobacillus as well. The antagonistic assay showed that biosurfactants were able to inhibit the formation of biofilms and growth of pathogens such as Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus cereus, Salmonella typhirium, Shigella boydii and Proteus mirabilis. The biosurfactant consortium (BioC) from Bacillus consortium and from Lactobacillus was able to inhibit biofilm formation and the pathogens growth. The BioC was stable to alkaline pH and the temperatures stability of Biosurfactant was ranging from 50°C to 90°C. The soap was made by the cold saponification process using one biosurfactant consortium formulated. This soap has a pH of 10 and showed good cleaning power and good foam stability. Similarly, the soap showed good antiseptic power and disinfection power against all pathogens tested. Handwashing is critical to preventing disease transmission. The persistence of pathogens in waste water was evaluated. The BioS produced showed good disinfection power against all pathogens tested. The valor of reduction on the hands and in the waste water was significantly more than compared to the control soaps used. This soap could be used in the prevention, fighting, and treatment of bacterial and viral infections.
基金Supported by the Scientific and Technological Development Program of Shijiazhuang City(08150132A)~~
文摘According to the theory of Chinese veterinary medicine and characteristics of Chinese herbal medicine, four different preparations of compound Chinese medicine ＂Zengrujianniusan＂ were composed, and the prepared water decoction was used to carry on the bacteriostatic test on main pathogens of cow recessiveness mastitis. The results showed that the four different prescriptions of water decoction all had antibacterial effects. The prescription 3 was sensitive to Staphylococcus aureus and Streptococcus agalactiae, while the other three prescriptions showed high sensitivity, and the prescription 3 had the strongest bacteriostatic effects.
基金supported by the Thailand Research Fund(TRF No. MRG508041)
文摘The objective of this study is to determine and compare the heavy metal（Zn,Cu,Cd,Pb） and bacterial（E.coli,coliform and Salmonella spp.） contamination between swine farms utilizing biogas and non-biogas systems in the central part of Thailand.Results showed that average levels of E.coli,coliform,BOD,COD,Zn,Cu and Pb in sludge from the post-biogas pond were higher than the standard limits.Moreover,the levels of E.coli,coliform,Cd and Pb were also higher than the standard limits for dry manure.The levels of E.coli,coliform and BOD on biogas farms were lower than on non-biogas farms.Following isolation of Salmonella spp.,it was found that Salmonella serovars Rissen was the most abundant at 18.46%（12/65）,followed by Anatum 12.31%（8/65）,and Kedougou 9.23%（6/65）.The pathogenic strains of Salmonella serovars Paratyphi B var.java and Typhimurium were present in equal amounts at 4.62%（3/65） in samples from all swine farms.This study revealed that significant reduction in E.coli and coliform levels in sludge from covered lagoon biogas systems on swine farms.The presence of Salmonella as well as Cd and Pb,in significant amount in dry manure,suggests that there is a high probability of environmental contamination if it is used for agricultural purposes.Thus,careful waste and manure disposal from swine farms and the regular monitoring of wastewater is strongly recommended to ensure the safety of humans,other animals and the environment.
文摘Application of compost in agricultural practice could potentially cause contamination of foodstuffs with pathogenic bacteria such as Escherichia coli O157：H7 （E. Coli O157）. We investigated pathogenic bacteria in compost collected from the compost facilities, and evaluated the survival of E. coli K12 and O157 in laboratory experiments. Out of 19 compost product samples, coliform bacteria and salmonella were detected in 7 and 3 samples respectively. The number of coliform bacteria was 1.8 × 10^2 to 2.5 × 10^6 CFU/g dw and that of salmonella was 4.2 × 10^1 to 6.0 × 10^3 CFU/g dw. Moreover. coliform bacteria, fecal coliform, E. coli and salmonella were detected during composting at 54℃ to 67℃. The results indicated that moisture content was a very important factor to the heat sensitivity of pathogenic bacteria in compost, E. coli in compost of high moisture content was more sensitive than that in compost of low moisture content, cells harvested in logarithmic phase was more sensitive than these in stationary phase, and E. coli K12 was more sensitive than E. coli O157. Based on the D values, the lethal time of E. coli K12 and 0157 from 10^8 to 10^0 CFU/g dw were 16.3 and 28.8 min, respectively, at 60℃ in compost with 40% moisture content. However, some E. coli cells survived in composting process at 54℃ to 67℃. Water potential（low moisture content） and physiological aspects of bacteria（stationary phase） could explain only in part of the prolonged survival of E. coli in compost, and there should be some other factors that are conducive to bacterial survial in compost.
基金supported by the National Natural Science Foundation of China(No.51478237)
文摘Pharmaceutical wastewater treatment plants（WWTPs） are thought to be a ＂seedbed＂ and reservoirs for multi-antibiotic resistant pathogenic bacteria which can be transmitted to the air environment through aeration. We quantified airborne multi-antibiotic resistance in a full-scale plant to treat antibiotics-producing wastewater by collecting bioaerosol samples from December2014 to July 2015. Gram-negative opportunistic pathogenic bacteria（GNOPB） were isolated, and antibiotic susceptibility tests against 18 commonly used antibiotics, including 11 β-lactam antibiotics, 3 aminoglycosides, 2 fluoroquinolones, 1 furan and 1 sulfonamide, were conducted.More than 45% of airborne bacteria isolated from the pharmaceutical WWTP were resistant to three or more antibiotics, and some opportunistic pathogenic strains were resistant to 16 antibiotics, whereas 45.3% and 50.3% of the strains isolated from residential community and municipal WWTP showed resistance to three or more antibiotics. The calculation of the multiple antibiotic resistance（MAR） index demonstrated that the air environment in the pharmaceutical WWTP was highly impacted by antibiotic resistance, while the residential community and municipal WWTP was less impacted by antibiotic resistance. In addition, we determined that the dominant genera of opportunistic pathogenic bacteria isolated from all bioaerosol samples were Acinetobacter, Alcaligenes, Citrobacter, Enterobacter, Escherichia, Klebsiella, Pantoea, Pseudomonas and Sphingomonas. Collectively, these results indicate the proliferations and spread of antibiotic resistance through bioaerosols in WWTP treating cephalosporin-producing wastewater, which imposed a potential health risk for the staff and residents in the neighborhood, calling for administrative measures to minimize the air-transmission hazard.
基金the National Natural Science Foundation of China(No.21575042)Project funded by China Postdoctoral Science Foundation(No.2019M663577)+2 种基金Applied Basic Research Programs of Yunnan Science and Technology Department(No.2018FH001–102)Talent Introduction Project of Kunming University(No.YJL18011)Innovative Practical Scientific Research Project of Kunming University(No.HXHG1805)。
文摘Pathogenic bacteria pose a global threat to public health and attract considerable attention in terms of food safety.Rapid and highly sensitive strategies for detecting pathogenic bacteria must be urgently developed to ensure food safety and public health.Microchips offer significant advantages for pathogenic bacterial detection in terms of speed and sensitivity compared with those of traditional techniques.Microfluidic devices,in particular,have attracted significant attention for the detection of pathogenic bacteria owing to their ease of operation,high throughput,cost-effectiveness,and high sensitivity.This review summarizes representative articles on the analysis of pathogenic bacteria using microchip-based systems.A detailed and comprehensive overview of microchip-based techniques for the detection of pathogenic bacteria is presented herein,and their advantages and disadvantages are discussed to compare their applications.The accomplishments and shortcomings of these microchips have been highlighted,and the direction of development and prospects of the analysis of pathogenic bacteria have been examined.The content of this review is anticipated to provide constructive suggestions for further development of highly effective and advanced microchip-based strategies for detecting pathogenic bacteria.
基金supported by Research and Development Program in Key Areas of Guangdong Province,China (No.2019B020209009)the National Natural Science Foundation of China (Nos. 21727814, 81872829 and 21621003)。
文摘Rapid on-site detection of pathogenic bacteria with high sensitivity and specificity is becoming an urgent need in public health assurance, medical diagnostics, environmental monitoring, and food safety fields. Despite being reliable and widely used, the existing methods of bacteria detection are cumbersome and time-consuming, which is not conducive to field detection. Microfluidic lab-on-a-chip technology has provided a detective tool for various analytes, due to its miniaturization, portability and low reagent consumption. Within this progress report, advances in the bacteria detection using microfluidic biosensors were discussed. Typical methods for pathogenic bacteria capture, separation and detection were introduced respectively in the first part. Then key applications of microfluidic biosensor-based rapid bacteria detection were presented. Finally, we made a conclusion and discussed possible research prospects in aspects of microfluidic biosensors for rapid detection of pathogenic bacteria.
文摘Edwardsiellosis of flounder and turbot occurring in different mariculture farms during 2001～ 2004 was examined, including the conditions of disease occurrence, clinical signs and pathological changes. The results showed that all diseased fishes expressed bacterial septicaemia. A total of 148 strains were identified using a combination of traditional physiological and biochemical tests and partial 16S rRNA gene analysis. In addition, the mole fraction G ＋ C ratio of the DNA of representative strain of isolates and serum homology were detected, and pathogenicity tests of isolates were conducted by experimental infection. The results revealed that 148 strains were identified as E. tarda of genus Edwardsiella, all the isolates are of serologic similarity, and have strong pathogenicity to flounder and turbot.
文摘Objective： To understand distribution and drug resistance of pathogenic bacteria from a specialized cancer hospital in 2013 in order to provide a basis for rational clinical antimicrobial agents. Methods： Pathogenic bacteria identification and drug sensitivity tests were performed with a VITEK 2 compact automatic identification system and data were analyzed using WHONET5.6 software.Results： Of the 1,378 strains tested, 980 were Gram-negative bacilli, accounting for 71.1%, in which Klebsiella pneumonia, Escherichia coli and Pseudomonas aeruginosa were the dominant strains. We found 328 Gram-positive coccus, accounting for 23.8%, in which the amount of Staphylococcus aureus was the highest. We identified 46 fungi, accounting for 4.1%. According to the departmental distribution within the hospital, the surgical departments isolated the major strains, accounting for 49.7%. According to disease types, lung cancer, intestinal cancer and esophagus cancer were the top three, accounting for 20.9%, 17.3% and 14.2%, respectively. No strains were resistant to imipenem, ertapenem or vancomycin.Conclusions： Pathogenic bacteria isolated from the specialized cancer hospital have different resistance rates compared to commonly used antimicrobial agents; therefore antimicrobial agents to reduce the morbidity and mortality of infections should be used.
基金We are grateful for the financial support from the National Natural Science Foundation of China(21878286,21908216,21576043)Dalian Institute of Chemical Physics(DICPI201938,DICP I202006).
文摘The harm of pathogenic bacteria to humans has promoted extensive research on physiological processes of pathogens,such as the mechanism of bacterial infection,antibiotic mode of action,and bacterial antimicrobial resistance.Most of these processes can be better investigated by timely tracking of fluorophore-derived antibiotics in living cells.In this paper,we will review the recent development of fluorescent antibiotics featuring the conjugation with various fluorophores,and focus on their applications in fluorescent imaging and real-time detection for various physiological processes of bacteria in vivo.
基金supported by the grants from the Genetically Modified Organisms Breeding Major Projects, China (2014ZX0800905B)the Fundamental Research Funds for the Central Universities, Chinathe Program for New Century 151 Talents of Zhejiang Province, China
文摘Phenazines are secondary metabolites with broad spectrum antibiotic activity and thus show high potential in biological control of pathogens. In this study, we identified phenazine biosynthesis （phz） genes in two genome-completed plant pathogenic bacteria Pseudomonas syringae pv. tomato （Pst） DC3000 and Xanthomonas oryzae pv. oryzae （Xoo） PXO99A. Unlike the phz genes in typical phenazine-producing pseudomonads, phz homologs in Pst DC3000 and Xoo PXO99A consisted of phzC/D/E/F/G and phzC/E1/E2/F/G, respectively, and the both were not organized into an operon. Detection experiments demonstrated that phenazine-l-carboxylic acid （PCA） of Pst DC3000 accumulated to 13.4 IJg L-1, while that of Xoo PXO99A was almost undetectable. Moreover, Pst DC3000 was resistant to 1 mg mL-1 PCA, while Xoo PXO99A was sensitive to 50 IJg mL ~ PCA. Furthermore, mutation of phzF blocked the PCA production and significantly reduced the pathogenicity of Pst DC3000 in tomato, while the complementary strains restored these phenotypes. These results revealed that Pst DC3000 produces low level of and is resistant to phenazines and thus is unable to be biologically controlled by phenazines. Additionally, phz-mediated PCA production is required for full pathogenicity of Pst DC3000. To our knowledge, this is the first report of PCA production and its function in pathogenicity of a plant pathogenic P. syringae strain.
文摘In recent years, researchers tended to bring new alternative to biological protective systems used in conservation of food and production of safe food. Use of bacteriophage against to pathogen bacteria in food was the most hopeful system in these methods about bio-control. Controls of bacteriophage for each pathogen species and subspecies and determination of phage-host originality are important because efficient bio-control was achieved. Researches concentrated on some food-borne pathogen bacteria such as E. coli O157：H7, Campylobacter, Salmonella and Listeria. In a consequence of these studies made as in vitro and in vivo, first commercial production of phage which will be used in foods was made in Netherlands. Also, it has been informed that use of phage is cost-efficient alternative as compared with other preservatives. This review, discussed application of bacteriophages as bio-control agents in food and advantages and disadvantages about uses of bacteriophages by taking into account antimicrobial characteristics of them.
文摘Antibiotic resistant bacteria pass between humans, between animals and between humans and animals in both directions, the use of antibiotics in poultry has contributed to multiple antibiotic resistant in pathogenic bacteria and use of two antibiotics might prevent the emergence of resistance to either. In this study, synergistic effect of combined antibiotics against multidrug resistant human pathogenic bacterial isolates from poultry droppings in Akure, Nigeria was examined. Collection of samples, isolation and identification of bacteria were carried out using standard microbiological method, antibiotic sensitivity test was performed by disc diffusion method and zone of inhibition was used to interpret the sensitivity test as resistant, susceptible or intermediate while combined effects of two antibiotics were investigated by macrobroth dilution and checkerboard assay methods while the synergetic effects of combined antibiotics were calculated using Fractional Inhibitory Concentration (FIC) and percentage synergistic interaction was calculated. All the ten (10) species of bacterial isolates were multidrug resistant and are less resistant to ofloxacin. The highest percentage synergistic interactions observed were Ofloxacin + Amoxicillin (90%), Ciprofloxacin + Amoxicillin (90%), Tetracycline + Amoxicillin (70%), Tetracycline + Augmentin (80%), Cotrimoxazol + Amoxicillin (50%), Cotrimoxazol + Augmentin (70%), Chloramphenicol + Amoxicillin (70%) and Chloramphenicol + Augmentin (80%). Poultry droppings is a potential source of human pathogenic bacteria, high frequency of multiple antibiotic resistance bacteria observed in this study is of great treat to man as this may cause the treatment of infection caused by these bacteria to be difficult. Combination of beta-lactam antibiotic with fluoroqunolones, tetracycline, Chloramphenicol and Cotrimoxazole was synergetic and this will reduce dose related toxicity and prevent resistance to single antibiotic.
基金In-Hospital Fund Project of Affiliated Hospital of Hebei University:Analysis of Nosocomial Infection in Intensive Care Unit(2019Q030)。
文摘Objective:To understand the pathogenic bacteria isolated from patients and their drug resistance changes in general ICU of the Affiliated Hospital of Hebei University,so as to provide reference for appropriate selection of antibiotics in clinical practice.Methods:A retrospective investigation was conducted to analyze the bacteriological distribution and drug resistance of nosocomial pathogens isolated from the specimens of hospitalized patients in the comprehensive ICU of the hospital from 2019 to 2021.The US technology BD Phoenix 100 automatic bacterial identification analyzer was used for bacterial identification of the pathogen samples,disk diffusion method was used for drug susceptibility test,and SPSS 22.0 software was used to analyze the trend of drug resistance.Results:A total of 970 strains of nosocomial pathogens were detected in the three years.The main pathogens were Acinetobacter baumannii(133 strains,13.71%),Klebsiella pneumoniae(106 strains,10.93%),Pseudomonas aeruginosa(83 strains,8.56%),Escherichia coli(76 strains,7.84%)and Enterococcus faecium(69 strains,7.11%).The resistance rate of Acinetobacter baumannii to antibiotics was high.Klebsiella pneumoniae,Pseudomonas aeruginosa and Escherichia coli had low resistance rates to carbapenems.The situation of bacterial drug resistance is still serious.Conclusion:The drug resistance of pathogenic bacteria collected from Class III Grade A Hospital’s patients to antibiotics was generally high.Therefore,clinical departments should strengthen the inspection of specimens of infection and drug sensitivity test in order to grasp the resistance mechanisms and drug resistance of pathogenic bacteria changes,and select appropriate antimicrobial agents according to the test results.Besides,the formation of drug-resistant strains also needs to be prevented,and the treatment of patients with severe infection needs to be improved.
基金supported by the National Natural Science Foundation of China(11874021,61675072 and 21505047)the Science and Technology Project of Guangdong Province of China(2017A020215059)+2 种基金the Science and Technology Project of Guangzhou City(201904010323 and 2019050001)the Innovation Project of Graduate School of South China Normal University School(2019LKXM023)the Natural Science Research Project of Guangdong Food and Drug Vocational College(2019ZR01)
文摘Two-dimensional(2D)nanomaterials have captured an increasing attention in biophotonics owing to their excellent optical features.Herein,2D hafnium ditelluride(HfTe_(2)),a new member of transition metal tellurides,is exploited to support gold nanoparticles fabricating HfTe_(2)-Au nanocomposites.The nanohybrids can serve as novel 2D surface-enhanced Raman scattering(SERS)substrate for the label-free detection of analyte with high sensitivity and reproducibility.Chemical mechanism originated from HfTe_(2) nanosheets and the electromagnetic enhancement induced by the hot spots on the nano-hybrids may largely contribute to the superior SERS effect of HfTe_(2)-Au nanocomposites.Finally,HfTe_(2)-Au nanocomposites are utilized for the label-free SERS analysis of foodborne pathogenic bac-teria,which realize the rapid and ultrasensitive Raman test of Escherichia coli,Listeria mono-cytogenes,Staphylococcus aureus and Salmonella with the limit of detection of 10 CFU/mL and the maximum Raman enhancement factor up to 1.7×10^(8).Combined with principal component analysis,HfTe_(2)-Au-based SERS analysis also completes the bacterial classification without extra treatment.
基金This research was financially supported by the National Research Council of Thailand,Thailand and Kalasin University,Thailand.The authors also thanks the Department of Science and Mathematics,Faculty of Science and Health Technology and the Department of Biotechnology,Faculty of Agricultural Technology,Kalasin University for providing instruments.
文摘Objective:To assess the antibacterial activity of 5 selected plants against 4 pathogenic bacteria.Methods:Three solvents with different polarities were used to extract antimicrobial agents from the plants via maceration technique.The agar-disc diffusion technique was adopted to primarily screen antibacterial activities.Broth-dilution assay was employed to determine the minimum inhibitory concentration(MIC)and the minimum bactericidal concentration(MBC).Results:Among all extracts,the ethanol extract of Piper betle Linn showed the highest antibacterial activity against Gram-positive and the negative bacteria.MIC and MBC of the ethanol extract of Piper betle Linn against Salmonella typhimurium were the same(1?562.50 mg/L);while it showed the highest MIC and MBC against Pseudomonas aeruginosa of 6?250 mg/L and 12?500 mg/L,respectively.Conclusions:Salmonella typhimurium is the most susceptible bacteria while Pseudomonas aeruginosa is the most resistant bacteria towards the ethanol extract of Piper betle Linn.Piper betle possesses compounds with potential antibacterial activity and might be useful as an alternative to control infectious diseases.
文摘In this research,36 cows with clinical mastitis were treated with the Chinese herb injection Ruyuankang which was developed by our group.Milk samples of pre and post treatment of Ruyuankang were collected for isolation and characterization of pathogenic bacteria.The dynamic changes of pathogenic bacteria were investigated as well.The results indicated that Ruyuankang could effectively inhibit the common pathogenic bacteria of mastitis which result in the negative rate of pathogenic bacteria 71.74%.
文摘<strong>Background</strong>: Mealie Meal is one of the by-products of maize from dry milling. It constitutes more significant part of the daily diet of growing population of the Lusaka District of Zambia. However, reported cases of a cholera outbreak in October 2017-May 2018 were attributed to water contamination in the households of Lusaka. Hitherto there is no previous study or documented data for gastroenteritis caused by microbial contamination from food stores. <strong>Aim</strong>: The main objective of the study was to carry out species identification of Mealie meal spoilage organisms and pathogenic bacteria from selected food stores in Lusaka district from September 2019-March 2020. Crosssectional survey was conducted for food spoilage organisms and pathogenic bacteria of packaged maize meal flour from a selected food store. The number of packaged Mealie meal samples from selected food stores included in the study was 143 samples. Samples were obtained by a simple stratified random selection from food stores in Lusaka District. Thus Mealie Meal samples bought from Street food vendors were 96 (67%), Shops—30 (21%), Malls—17 (11.9%). Subsequently isolation by spread and pour plate methods, and species identification of microbial contamination by Cell Culture processes coupled to microbial morphological and biochemical characterization was performed. Microsoft Office Excel (version 2007) Spreadsheet was employed for the categorical data analysis and summarized graphical presentation of data. Laboratory findings revealed: Spoilage organisms—<em>Aspergillum</em> species, <em>Mucor</em> Species, <em>Candida</em> Species, <em>Clostridium</em> Species and <em>Bacillus</em> Species;Pathogenic Bacteria Species—<em>Clostridium perfringens</em>, <em>Staphylococcus aureus</em>, <em>Clostridium tetani</em>, <em>Bacillus</em>, <em>Escherichia coli</em>, <em>Pseudomonas aeruginosa</em> and <em>Yesinia pestis</em>. It can be established from the laboratory results earlier mentioned that the food poisoning outbreak could evolve from food stores in Lusaka district apart from water contamination.
