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PubMed2003

Influences of quinclorac on culturable microorganisms and soil respiration in flooded paddy soil.

OBJECTIVE: To investigate the potential effects of herbicide quinclorac (3,7-dichloro-8-quinoline-carboxylic) on the culturable microorganisms in flooded paddy soil. METHODS: Total soil aerobic bacteria, actinomycetes and fungi were counted by a 10-fold serial dilution plate technique. Numbers of anaerobic fermentative bacteria (AFB), denitrifying bacteria (DNB) and hydrogen-producing acetogenic bacteria (HPAB) were numerated by three-tube anaerobic most-probable-number (MPN) methods with anaerobic liquid enrichment media. The number of methanogenic bacteria (MB) and nitrogen-fixing bacteria (NFB) was determined by the rolling tube method in triplicate. Soil respiration was monitored by a 102G-type gas chromatography with a stainless steel column filled with GDX-104 and a thermal conductivity detector. RESULTS: Quinclorac concentration was an important factor affecting the populations of various culturable microorganisms. There were some significant differences in the aerobic heterotrophic bacteria. AFB and DNB between soils were supplemented with quinclorac and non-quinclorac at the early stage of incubation, but none of them was persistent. The number of fungi and DNB was increased in soil samples treated by lower than 1.33 micro x g(-1) dried soil, while the CFU of fungi and HPAB was inhibited in soil samples treated by higher than 1.33 microg x g(-1) dried soil. The population of actinomycete declined in negative proportion to the concentrations of quinclorac applied after 4 days. However, application of quinclorac greatly stimulated the growth of AFB and NFB. MB was more sensitive to quinclorac than the others, and the three soil samples with concentrations higher than 1 microg x g(-1) dried soil declined significantly to less than 40% of that in the control, but the number of samples with lower concentrations of quinclorac was nearly equal to that in the control at the end of experiments. CONCLUSION: Quinclorac is safe to the soil microorganisms when applied at normal concentrations (0.67 microg x g(-1)).

Bacteria, Anaerobic↗
PubMed2004

Granulation of Anammox microorganisms in up-flow reactors.

Experimental studies were performed to evaluate the feasibility of granulation of Anammox microorganisms for biomass retention in up-flow reactors. Two experimental studies, one using a 6.4-L lab-scale reactor with synthetic medium and the other using a 200-L pilot-scale reactor with half-nitrified reject water from a sludge digester were conducted. To enhance the granulation process, seed granules from a UASB reactor were added to both experimental reactors. Granulation of Anammox microorganisms was observed using both the synthetic medium and the reject water. The core of a large proportion of Anammox granules retained part of the original seed biomass. The Anammox granules had a slightly lower density than the seed granules from the UASB process, but the size and other physical properties were comparable. The successful granulation of the Anammox microorganisms led to a stable nitrogen removal performance. The maximum nitrogen removal rate of the lab-scale reactor was observed to be 2.9 kg/(m3 x d) after 173 days of operation and that of the pilot-scale reactor was 6.4 kg/(m3 x d) after 12 months of operation.

Biomass↗
PubMed2004

Dissimilatory reduction of FeIII (EDTA) with microorganisms in the system of nitric oxide removal from the flue gas by metal chelate absorption.

In the system of nitric oxide removal from the flue gas by metal chelate absorption, it is an obstacle that ferrous absorbents are easily oxidized by oxygen in the flue gas to ferric counterparts, which are not capable of binding NO. By adding iron metal or electrochemical method, FeIII(EDTA) can be reduced to FeII(EDTA). However, there are various drawbacks associated with these techniques. The dissimilatory reduction of FeIII(EDTA) with microorganisms in the system of nitric oxide removal by metal chelate absorption was investigated. Ammonium salt instead of nitrate was used as the nitrogen source, as nitrates inhibited the reduction of FeIII due to the competition between the two electron acceptors. Supplemental glucose and lactate stimulated the formation of FeII more than ethanol as the carbon sources. The microorganisms cultured at 50 degrees C were not very sensitive to the other experimental temperature, the reduction percentage of FeIII varied little with the temperature range of 30-50 degrees C. Concentrated Na2CO3 solution was added to adjust the solution pH to an optimal pH range of 6-7. The overall results revealed that the dissimilatory ferric reducing microorganisms present in the mix-culture are probably neutrophilic, moderately thermophilic FeIII reducers.

Absorption↗
PubMedDate not supplied

[Characteristics of microflora isolated in chronic adnexitides and effects of balneotherapy on biological properties of microorganisms in experimental and clinical conditions].

The study of species and biology of microflora isolated from 42 patients with chronic adnexitides has detected a wide spectrum of pathological agents among which both aerobic and anaerobic microorganisms were encountered. The isolated cultures were examined for ability to inactivate lysozyme, complement and lactoferrin. The experiments have established changes in biological properties of the microorganisms in response to use of mud and salty brine therapy. Clinical investigations demonstrate the ability of balneotherapy to restore normal flora, to reduce contamination with opportunistic microflora and suppress biological, including persistent, properties of microorganisms in females with chronic adnexitides. Positive effects of balneotherapy seem to base, primarily, on this ability.

Adult↗
PubMedDate not supplied

[Microorganisms surviving in drinking water systems and related problems].

Drinking water in distribution systems may show abnormal values of some parameters, such as turbidity, and may support particular phenomena, such as bacterial regrowth or presence of Viable Not Culturable (VNC) bacteria. Turbidity can provide shelter for opportunistic microorganisms and pathogens. The Milwaukee outbreak (400,000 people) is one example of waterborne disease caused by the presence of pathogens (Cryptosporidium) in drinking water characterized by high and intermittent levels of turbidity. Bacterial regrowth in drinking water distribution systems may cause high increments of microorganisms such as heterotrophic bacteria, coliforms and pathogens. Microorganisms isolated from biofilm including Pseudomonas, Aeromonas, Legionella may have a significant health hazard especially in hospital areas. The presence of VNC bacteria in drinking water may represent a problem for their discussed role in infectious diseases, but also for the possibility of a considerable underestimation of true microbial concentrations in drinking waters. To study this kind of problems is necessary to apply suitable methods for drinking water analyses.

Bacteria↗
PubMed2004

Exposure to airborne microorganisms, dust and endotoxin during flax scutching on farms.

Microbiological air sampling was performed on 5 flax farms located in eastern Poland. Air samples for determination of the concentrations of microorganisms, dust and endotoxin were collected in barns during machine scutching of flax stems by the farmers. The concentrations of mesophilic bacteria ranged from 203.5-698.8 x 10(3) cfu/m3, of Gram-negative bacteria from 27.2-123.4 x 10(3) cfu/m3, of thermophilic actinomycetes from 0.5-2.6 x 10(3) cfu/m3, and of fungi from 23.4-99.8 x 10(3) cfu/m3. The concentrations of total airborne microorganisms (bacteria + fungi) were within a range of 245.0-741.0 x 10(3) cfu/m3. The values of the respirable fraction of total airborne microflora on the examined farms were between 45.5-98.3%. Corynebacteria (irregular Gram-positive rods, mostly Corynebacterium spp.) were dominant at all sampling sites, forming 46.8-67.8% of the total airborne microflora. Among Gram-negative bacteria, the most numerous species was Pantoea agglomerans (synonyms: Erwinia herbicola, Enterobacter agglomerans), known to have strong endotoxic and allergenic properties. Among fungi, the allergenic species Alternaria alternata prevailed. Altogether, 25 species or genera of bacteria and 10 species or genera of fungi were identified in the farm air during flax scutching; of these, 11 and 6 species or genera respectively were reported as having allergenic and/or immunotoxic properties. The concentrations of airborne dust ranged within 43.7-648.1 mg/m3 (median 93.6 mg/m3), exceeding on all farms the Polish OEL value of 4 mg/m3. The concentrations of airborne endotoxin ranged within 16.9-172.1 microg/m3 (median 30.0 microg/m3), exceeding at all sampling sites the suggested OEL value of 0.2 microg/m). In conclusion, flax farmers performing machine scutching of flax could be exposed to large concentrations of airborne microorganisms, dust and endotoxin, posing a risk of work-related respiratory disease.

Agriculture↗
PubMed2004

[Development of a ground-based experimental facility for space waste material processing with microorganism].

OBJECTIVE: To develop a ground-based experimental facility for microorganism waste processing, which will be used to recover nutrient from plant inedible biomass essential for growth and development of plants. METHOD: After technical parameters and performance requirements were defined, planning demonstration, drawing design, fabrication, debug and plant inedible residue-biodegradation tests by microorganisms were conducted. RESULT: The facility worked well, and the parameters, such as energy consumption, volume and weight, met the design requirement. The water-treated quality and the ability of treating plant residual by microorganism were better than the demands. The ground-based results demonstrated that total organic carbon (TOC) degradation above 92.1%, and chemical oxygen demand (COD) reduction over 95.5% could be maintained. CONCLUSION: The facility has reasonable technical indexes, and smooth and reliable performances. Its major working principle is suitable for the demand of space conditions. It is capable of being utilized for biodegradation of plant inedible biomass in space.

Aspergillus niger↗
PubMed2005

Exposure to airborne microorganisms, dust and endotoxin during processing of valerian roots on farms.

The aim of this study was to determine the levels of microorganisms, dust and endotoxin in the air during various stages of valerian (Valeriana officinalis) roots processing by herb farmers and to examine the species composition of airborne microflora. Air samples were collected on glass fibre filters by use of personal samplers on 15 farms owned by valerian cultivating farmers, located in Lublin province (eastern Poland). The concentrations of total viable microorganisms (bacteria + fungi) in the air showed a marked variability and were within a range of 0.95-7,966.6 x 10(3) cfu/m (3). Though median was relatively low (10.75 x 10(3) cfu/m (3)), on 4 farms the concentrations exceeded the level of 10(5) cfu/m (3) and on 1 farm the level of 10(6) cfu/m (3). During the processing of valerian roots, distinct changes could be observed in the composition of airborne microflora. In the first stages of processing, the freshly dug and washed roots until shaking in the drying room, the most numerous were Gram-negative bacteria of the family Pseudomonadaceae (mostly Stenotrophomonas maltophilia, Pseudomonas chlororaphis and Pseudomonas fluorescens). After drying, the dominant organisms were thermo-resistant endospore-forming bacilli (Bacillus spp.) and fungi, among which prevailed Aspergillus fumigatus. Altogether, 29 species or genera of bacteria and 19 species or genera of fungi were identified in the farm air during valerian processing, of these, 10 and 12 species or genera respectively were reported as having allergenic and/or immunotoxic properties. The concentrations of airborne dust and endotoxin on the examined farms were very large and ranged from 10.0-776.7 mg/m (3), and from 0.15-24,448.2 microg/m (3), respectively (medians 198.3 mg/m (3) and 40.48 microg/m (3)). In conclusion, farmers cultivating valerian could be exposed during processing of valerian roots to large concentrations of airborne microorganisms, dust and endotoxin posing a risk of work-related respiratory disease.

Agricultural Workers' Diseases↗
PubMed2005

[An analysis of microorganisms isolated from blood samples of patients treated at the Department of Nephrology and Internal Diseases].

UNLABELLED: The development of invasive medical procedures involves a decrease of prevalence of generalized infections. Hemodialysed patients are at higher risk of infection. The aim of this study was to analyze microorganisms isolated from blood samples of patients treated at the Department of Nephrology and Internal Diseases of the Medical University in Bydgoszcz. MATERIAL AND METHODS: The analysis was based on 959 blood samples obtained from 248 patients during the investigation period from 01.02.2001 to 30.11.2002. Among patients included in this analysis 52.0% were males, 48.0% females. The age oscillated between 18 and 95 years, average 58.6 +/- 17.6. Blood cultures were processed in the blood culture monitoring systems. Identification of isolated microorganisms was based on their morphological and biochemical features. Antibiotic sensitivity tests were conducted according to the recommendations of the NCCLS and National Reference Centre for Drug-Sensitivity of Microorganisms. RESULTS: Positive culture results were obtained for 151 (15.8%) samples. 1114 (75.5%) strains of Gram(+) bacteria and 36 (23.8%) strains of Gram(-) bacteria and one Candida albicans strain were isolated. The results of antibiotic sensitivity tests are also presented. High prevalence of CNS strains in our research may suggest contamination of the samples with normal skin flora, since those strains were usually only isolated one time. It might also be the result of the profile of the Department. CONCLUSIONS: The prevention of vascular access-related septicaemia is a vital element of the care of the hemodialysed patient, as it is a well-established risk factor of generalized infections. Elaborating of local standards for empirical antibiotic therapy of generalized infections based on the epidemiological data of a particular department or hospital ward is necessary.

Adult↗
PubMedDate not supplied

[Succession of chitinolytic microorganisms in chernozem soil].

The chitinolytic prokaryotic and eukaryotic microbial complex of chernozem soil has been investigated in the course of a succession initiated by the introduction of chitin and humidification. The dynamics of the cell numbers of chitinolytic microorganisms and of their biomass was assessed by fluorescent microscopy and by inoculation of selective media. Emission of carbon dioxide and nitrous oxide, as well as dinitrogen fixation, was assessed by gas chromatography. It was found that, when the succession was initiated by the introduction of both chitin and humidification, it resulted in greater cell numbers and biomass of chitinolytic microorganisms and higher levels of CO2 and N2O emission and of nitrogen fixation than when the succession was initiated by humidification alone. As compared to the control samples, a significant (twofold) increase in the prokaryote cell number and biomass was found on the fourth day of the succession initiated by humidification and introduction of chitin. One week after the initiation of succession, the fungal biomass and length of mycelium were twice as high as those in the control samples. These results led to the conclusion that chitin utilization in chernozem soil starts during the initial stages of succession and is performed by both prokaryotic and eukaryotic microorganisms.

Actinobacteria↗
PubMed2005

Exposure to airborne microorganisms, dust and endotoxin during processing of peppermint and chamomile herbs on farms.

The aim of this study was to determine the levels of microorganisms, dust and endotoxin in the air during processing of peppermint (Mentha piperita) and chamomile (Matricaria recutita) by herb farmers, and to examine the species composition of airborne microflora. Air samples were collected on glass fibre filters by use of personal samplers on 13 farms owned by herb cultivating farmers, located in Lublin province (eastern Poland). The concentrations of total viable microorganisms (bacteria + fungi) in the farm air during processing of peppermint herb were large, within a range from 895.1-6,015.8 x 10(3) cfu/m(3) (median 1,055.3 x 10(3) cfu/m(3)). During processing of chamomile herb they were much lower and varied within a range from 0.88-295.6 x 10(3) cfu/m(3) (median 27.3 x 10(3) cfu/m(3)). Gram-negative bacteria distinctly prevailed during processing of peppermint leaves, forming 46.4-88.5 % of the total airborne microflora. During processing of chamomile herb, Gram-negative bacteria were dominant at 3 out of 6 sampling sites forming 54.7-75.3 % of total microflora, whereas at the remaining 3 sites the most common were fungi forming 46.2-99.9 % of the total count. The species Pantoea agglomerans (synonyms: Erwinia herbicola, Enterobacter agglomerans ), having strong allergenic and endotoxic properties, distinctly prevailed among Gram-negative isolates. Among fungi, the most common species was Alternaria alternata. The concentrations of airborne dust and endotoxin determined on the examined herb farms were large. The concentrations of airborne dust during peppermint and chamomile processing ranged from 86.7-958.9 mg/m(3), and from 1.1-499.2 mg/m(3), respectively (medians 552.3 mg/m(3) and 12.3 mg/m(3)). The concentrations of airborne endotoxin determined during peppermint and chamomile processing were within a wide range 1.53-208.33 microg/m(3) and 0.005-2604.19 microg/m(3) respectively (medians 57.3 microg/m(3) and 0.96 microg/m(3)). In conclusion, farmers cultivating peppermint are exposed during processing of this herb to large concentrations of airborne microorganisms, dust and endotoxin posing a risk of work-related respiratory disease. The exposure to bioaerosols during processing of chamomile is lower; nevertheless, peak values create a respiratory risk for exposed farmers.

Agricultural Workers' Diseases↗
PubMed2006

[Simultaneous control of microorganism, disinfection by-products and bio-stability by sequential chlorination disinfection].

A new safe chlorination disinfection process, the sequential disinfection process with short-term free chlorine plus chloramines was investigated its efficiency on control of indices of microorganism, disinfection by-products and bio-stability. This disinfection process may take the advantage of free chlorine's quick inactivation of microorganism and chloramines' low DBP yield and long-term residual. Thus, both control of microorganisms and DBPs can be achieved effectively and economically. The pilot test results show that safe chlorination disinfection process has a little better efficiency on total bacteria count, HPC and total coliform count than free chlorination disinfection, which indicate that free chlorine and chloramines might have the synergetic disinfection effect for their different attacking targets. It also had the same inactivation efficiency on polio virus and coliphage f2 as free chlorination in 120 minutes contact time. Sequential chlorination disinfection process could reduce 35.8% - 77.0% yield of trihalomethane and 36.6% - 54.8% yield of haloacetic acids. The poorer quality the water had, the more advantage the safe-chlorination disinfection had than free chlorination disinfection one. Moreover, sequential chlorination had better efficiency on bio-stability control than free chlorination.

Chloramines↗
PubMed2006

[Effects of selective extraction on microorganisms on biomembrane in natural water body].

By the methods of direct viable count and plate count, this paper studied the effects of different selective extractants on the bacteria, algae and protozoan on the biomembrane in natural water body. The results indicated that the stronger the extraction ability of selective extractant, the fewer the living microorganisms on the biomembrane after extraction. Compared with the control, the percentages of living microorganisms on the biomembrane were 27.6, 14.1 and 0.01, respectively, after extracted by hydroxylamine hydrochloride (0.01 mol x L(-1) NH2OH.HCl + 0.01 mol x L(-1) HNO3), sodium dithionite (0.4 mol x L(-1) Na2S2O4, pH 6.0), and acidified ammonium oxalate. Very few bacteria was left after extracted by nitric acid (15% HNO3), and no microorgariisms could be detected after extracted by H2O2/HNO3, suggesting that the use of selective extractants affected the activity of biomembrane. With the decreasing amount of microorganisms on the biomembrane after treated with selective extractants, the adsorption of heavy metals by the biomembrane was gradually depressed.

Bacteria↗
PubMed2005

[Microorganisms analysis in Public Clinical Hospital in Gdańsk over three years 2001-2003].

The aim of the study was to analyse the changes in occurence of microorganisms and antibiotic usage in tertiary care hospital over 3 years. We analysed the results of microbiological records from laboratory inforation systems from 2001 to 2003. Over the study period there was about 40% increase of specimens received in the laboratory mainly due to another hospital incorporation. The relations between different groups of microorganisms was stable, Gram negatives 44,4%-46,3%, Gram positives 37,3%-40,3%, yeasts 7,0%-8,1%. There was a decrease in MRSA from 0,6% to 0,2% and carbapenem resistant Pseudomonas aeruginosa (CRPA) isolations from 2,0% to 0,7%, however the reverse was true for VRE, increase from 0,3% to 2%. ESBL-producing bacteria were isolated from about 4% of Enterobacteriaceae throughout the study. The analysis of blood cultures revealed over 60% deacrease in P. aeruginosa bacteremia and stable incidence of Escherichia coli (7%) and Staphylococcus aureus (6,5%) bacteremia. Increased usage of cephalosporins and fluoroquinolones was accompanied by the decrease in carbapenems and penicillins. In most cases there were no significant changes in occurence of main groups of microorganisms. Some multidrug resistant bacteria like MRSA and CRPA are no longer a problem in our hospital. Others like VRE, ESBL and Acinetobacter still cause concern due to high colonisation or infection rate. The usage of some antibiotic groups increased, another decreased and finally some like aminoglicosides and glicopeptides remained stable.

Bacteremia↗
PubMed2006

[Clinical observation on acupuncture combined with microorganism pharmaceutical preparations for treatment of irritable bowel syndrome of constipation type].

OBJECTIVE: To explore the best program for treatment of irritable bowel syndrome (IBS) of constipation type. METHODS: Ninety-five cases of IBS were randomly divided into 3 groups. Group A (n = 30) were treated by acupuncture combined with microorganism pharmaceutical preparations, group B (n = 35) by oral administration of medicine for loosening the bowel to relieve constipation plus microorganism pharmaceutical preparations, and group C (n = 30) by simple acupuncture. RESULTS: The total effective rates were 90.0%, 77.2% and 66.7%, in the group A, B and C, respectively, with a very significant differences as the group A compared with those in the groups B, C (P < 0.01), and with no significant difference as the group B compared with that of the group C (P > 0. 05). The intestinal available bacteria, bilidobacteria and lactobacillus, increased and enteric bacilli decreased in varying degrees in the 3 groups. CONCLUSION: Acupuncture combined with microorganism pharmaceutical preparations has a better therapeutic effect on irritable bowel syndrome of constipation type.

Acupuncture Therapy↗
PubMed2006

Presence of opportunistic oil-degrading microorganisms operating at the initial steps of oil extraction and handling.

Hydrocarbon-degrading microorganisms from natural environments have been isolated and identified using culture-dependent or molecular techniques. However, there has been little research into the occurrence of microorganisms incorporated into crude oil in the initial steps of extraction and handling, which can reduce the quality of stored petroleum. In the present study, a packed-column reactor filled with autoclaved perlite soaked with crude oil was subjected to a continuous flow of sterile medium in order to determine the presence of potential hydrocarbon degraders. Microorganisms developed on the surface of the perlite within a period of 73 days. DNA was extracted from the biofilm and then PCR-amplified using 16S rRNA bacterial and archaeal primers and 18S rRNA eukaryotic primers. No amplification was obtained using archaeal primers. However, denaturing gradient gel electrophoresis (DGGE) revealed the presence of unique bands indicating bacterial and eukaryotic amplification. Excision of these bands, sequencing, and subsequent BLAST search showed that they corresponded to Bacillus sp. and Aspergillus versicolor. The fungus was later isolated from intact perlite in agar plates. A bacterial clone library was used to confirm the presence in the biofilm of a unique hydrocarbon-degrading bacterium closely related to Bacillus sp. Analysis of the petroleum components by gas chromatography showed that there n-alkanes, aromatic hydrocarbons, and carbazoles were degraded.

Aspergillus↗
PubMed2006

[Microorganisms isolated from middle ear cultures and their antibacterial susceptibility in patients with chronic suppurative otitis media].

OBJECTIVES: This study sought to determine causative microorganisms of chronic suppurative otitis media and their antibacterial susceptibility. PATIENTS AND METHODS: Bacteriologic results of middle ear swabs, agent microorganisms, and their susceptibility to antibiotics were evaluated in 70 patients (65 males, 5 females; mean age 21.1+/-1.3 years; range 19 to 25 years) with chronic suppurative otitis media. RESULTS: No bacteria were isolated in 14% of the patients. Of 60 patients in whom bacteria were isolated, the most common bacteria was Pseudomonas aeruginosa (23%), followed by Staphylococcus aureus (18%), and Proteus spp. (17%). P. aeruginosa strains were susceptible to ceftazidime and imipenem (100%), ciprofloxacin (92%), and amikacin and gentamycin (85%); S. aureus strains were susceptible to methicillin and vancomycin (100%), ciprofloxacin (91%), sulbactam-ampicillin (73%), and gentamycin and trimethoprim-sulfamethoxazole (63%). Proteus strains were susceptible to ciprofloxacin (100%), ceftazidime (90%), and imipenem and gentamycin (70%). CONCLUSION: Appropriate knowledge of antibacterial susceptibility of microorganisms will contribute to rational antibiotic usage and the success of treatment for chronic suppurative otitis media.

Adult↗
PubMedDate not supplied

[Symbiosis in survival of microorganisms in hyperhaline water reservours].

Differently directed effects from autochthonous algae and bacteria on allochthonous microflora in hyperosmotic conditions were revealed and analyzed. Living halophilic microorganisms increase survival time of enterobacteria. Cellular extracts from halophils decrease storage time of allochthonous bacteria in a highly mineralized medium. Allochthonous bacteria in hyperosmotic conditions are able to suppress viability of autochthonous halophilic microflora. Symbiotic interactions between autochthonous and allochthonous microorganisms, defined by correlation of protective and antagonistic effects, regulate survival of microorganisms in hyperhaline water reservours and can be used for the assessment of their ecological and sanitary-and-hygienic states.

Chlorophyta↗