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1.
The comparative decomposition of chickpea residue, and chopped and unchopped wheat straw was investigated in pits for 120 days. Microbial biomass, humus, C/N ratio, pH, Electrical conductivity (EC), dehydrogenase, alkaline phosphatase, cellulase, xylanase, total phenol and soluble protein were determined to assess their response to the addition of inorganic nitrogen and mixed fungal inoculum of Aspergillus nidulans, Phanerochaete chrysosporium and Trichoderma viride. The evaluation of physico-chemical parameters (organic matter, organic carbon, N, C/N, pH, EC, microbial biomass) revealed that by supplementing unchopped wheat straw with 1% urea and mixed fungal inoculum, a lowest C/N ratio of 10.7, lowest biomass of 9.54 and highest humus content of 13% can be achieved within 3 months. Germination of Lepidium sativum (cress seeds) showed a germination index >60%, in this treatment. The enzyme assay for dehydrogenase indicated highest microbial activity in uninoculated treatments compared to fungal inoculated counterparts, in the second month sampling (active phase of composting). However, cellulase and xylanase activity showed an upward trend during curing phase of composting. Chickpea residue compost, though resulted in a C/N ratio of 17.3, but its germination index was less than 60%. The rapid quality tests conducted for H2S, NH3, NO3 and starch confirmed the stability and maturity of finished compost prepared from wheat straw through microbial inoculants.  相似文献   

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3.
《Clinical microbiology and infection》2020,26(9):1259.e1-1259.e3
ObjectivesLegionella is a bacterial species able to cause influenza-like illness (Pontiac fever) or severe pneumonia (Legionnaires disease, LD). We assessed Legionella presence and concentration in composting facilities in The Netherlands.MethodsA total of 142 samples from 23 green waste composting facilities were screened for Legionella DNA using qPCR.ResultsOf 142 samples, Legionella spp. DNA was detected in 97 (68%), and the subspecies L. pneumophila and L. longbeachae in 33 (23%) and one (0.7%) samples, respectively. Legionella was observed in samples from all composting facilities. The concentration of Legionella spp. DNA ranged from 103 to 105 genomic units (GU)/gram. Compost temperature was negatively correlated with the presence (odds ratio 0.67, 95% CI 0.50–0.92 per 10 degrees increase) and concentration (geometric mean ratio 0.90, 95% CI 0.83–0.97 per 10 degrees) of Legionella spp. Average humidity in the week prior to sampling was negatively correlated with the L. pneumophila concentration (geometric mean ratio 0.73, 95% CI 0.56–0.96 per increase in 10% of humidity).DiscussionThis study suggests that composting facilities can be regarded as reservoirs of Legionella in The Netherlands, but additional studies should target if such facilities represent a human health risk.  相似文献   

4.
Actinobacteria are believed to play a major role in organic matter degradation and humification processes in composts. In this study, the effects of different temperature regimes on the succession of Actinobacteria populations during composting were investigated in a laboratory reactor. Phospholipid fatty acid (PLFA) was used to investigate quantitative changes in the overall microbial biomass and community structure, and in the size of Actinobacteria populations. Qualitative changes were determined using PCR-DGGE (denaturing gradient gel electrophoresis) and sequencing of 16S rRNA genes with Actinobacteria-specific primers. The peak in total microbial biomass was roughly twice as high and delayed in trials where the maximum temperature was 40 degrees C, compared to those where it was 55 or 67 degrees C. There was a shift from members of Corynebacterium, Rhodococcus and Streptomyces at the onset to species of thermotolerant Actinobacteria in the cooling phase, e.g. Saccharomonospora viridis, Thermobifida fusca and Thermobispora bispora. In conclusion, temperature was an important selective factor for the development of Actinobacteria populations in composts, and they constituted a substantial part of the community in the later compost stages.  相似文献   

5.
This study investigates the prevailing microbial communities during the composting of vegetable waste, cattle manure and saw dust, in a household (250 l) batch scale Rotary Drum composter and Windrow Pile. Physico-chemical parameters were analyzed to study the organic matter transformations. Total organic matter reduced from 63.8% to 36.2% in rotary drum and 39.6% in windrow pile composting. The C/N ratio decreased from 26.52 to 8.89 and 14.33 in rotary drum and windrow pile composting. The indigenous population of total heterotrophic bacteria decreased in rotary drum and windrow pile composting after 20 days. However, total fungal load initially increased within initial 4 days, then subsequently reduced in final composts. The average number of fecal coliforms and fecal Streptococci showed decrement with time, in both composting systems. Escherichia coli and Salmonella species number deduced during the study. Composting cycle started with Gram positive rods but ended up with the dominance of Gram negative bacilli shaped bacteria. Transformation of organic compounds during the biodegradation of organic waste, difference in the utilization of nutrients (organic matter) by the different group of microbes and high temperature could be cited as a possible reason of the above changes. Scanning electron microscopy has been used to obtain the surface structures of the cultured mycoflora. Results of the study revealed that higher diversity of microbes prevailed in rotary drum as compared to windrow pile, yielding more stable and pathogenic free compost in lesser period of composting.  相似文献   

6.
Herbal antimalarials still remain an alternative to our traditional communities who can not afford orthodox antimalarials. This study was aimed at investigating the microbial quality of six herbal antimalarials using standard microbiological methods. Of the six preparations analyzed, “schnapps”, palm wine and water were the media of preparation; the water base preparations recorded higher microbial load. The mean microbial load was 159.5×105 cfu/ml and 217.4×102cfu/ml in water and alcohol base preparations respectively. The microbial profile of the preparations showed that the schnapps base preparations were predominantly contaminated with Bacillus sp (Aerobic spore bearers) and Mucor spp. The palm wine preparation harboured Bacillus sp, yeasts and Mucor spp while the water base preparations had several isolates such as Staphylococcus epidermidis, Pseudomonas aeruginosa, Escherichia coli 0157H7, Proteus mirabilis, Enterococcus feacalis, Serratia marcensces, Staph. aureus, Bacillus spp and Mucor spp. Conclusively, this study underlines the public health importance of these preparations given the high burden of such human pathogen as Ecoli O157H7, Ps aeruginosa, Stahp aureus, etc. in the preparations.  相似文献   

7.
BackgroundBacterial pneumonia is a well-recognized sequela of patient suffering from influenza, and a key factor, with cytokine dysregulation, that contribute to severe disease and mortality.ObjectivesTo obtain a comprehensive assessment of lung microbial community dynamics in a fatal influenza H7N9 case during the whole clinical course, we undertook a longitudinal study.Study designSerial bronchoalveolar lavage fluid samples were collected from a H7N9 patient after illness onset, and the microbiome was characterized by using next-generation sequencing and microbiological approaches. Furthermore, the kinetics of circulating cytokine storms related to viral and secondary bacterial infection were analyzed.ResultsWithin complex and dynamic communities, the lung microbiome with H7N9 infection were dominated by gram-negative bacteria, Acinetobacter baumannii after the viral invasion and during the whole clinical course. Sputum and blood culture confirmed the secondary bacterial infection with multidrug-resistant A. baumannii 9 days later. The dynamics of the bacterial infection with carbapenem-resistant A. baumannii correlated with antibiotic therapy. Our observations also indicated that sustained high levels of host inflammatory factors, consisting of a set of distinct cytokines associated with disease stage, may contribute to disease progression and death.ConclusionsThis study demonstrates an initial attempt to explore the dynamic microbiome involved inH7N9 infection and its response to antimicrobial therapy, as well as host cytokine response to infection by using next-generation sequencing. These type of investigations with longitudinal follow-up to understand dynamics of microbial community and cytokines involved in lung infection may provide opportunities for development and optimization of targeted antimicrobial therapy and even new therapeutic strategies.  相似文献   

8.
This study investigated various biological activities of the ethanolic extract of dried ground leaves of Schefflera leucantha Viguier (Araliaceae). The extract possessed very low cytotoxicity to brine-shrimp with the LC50 of 4,111.15µg/ml; the significant antioxidant activity on DPPH with the EC50 of 71.90µg/ml; the inhibitory activity on mushroom tyrosinase with the IC50 of 10.53mg/ml using the dopachrome microplate-assay. The extract of 5–20mg/ml range in the agar dilution assay were active against various pathogenic microbial (11 species, 11 strains), with the minimum inhibitory concentration (MIC) of 5mg/ml against Clostridium spp.; MIC=10mg/ml against enteropathogens as Bacteroides spp., Enterococcus faecalis ATCC 29212, Lactobacillus spp., Peptococcus spp. and Streptococcus mutans; MIC=10mg/ml against a pneumonia causing bacteria Klebsiella pneumoniae and a dermatopathogen as Propionibacterium acnes; MIC=20mg/ml against dermatopathogens as Staphylococcus aureus ATCC 6538, Streptococcus spp. and Candida albicans ATCC 90028. TLC fingerprints of the specific extracts from the leaf powder exhibited zones of steroids-terpenes and flavonoids. HPLC fingerprint of the flavonoid extract was performed.  相似文献   

9.
The antibacterial activity of norfloxacin, an organic acid structurally related to nalidixic acid, was compared with that of the oral cephalosporins cefaclor and cephalexin, and with that of nalidixic acid, cinoxacin, amikacin, ampicillin, trimethoprim alone and the combination of trimethoprim and sulfamethoxazole. Agar dilution studies were performed with a total of 398 clinical isolates of gram-negative bacteria, Norfloxacin was found to be the most active drug studied against each of the different groups of organisms tested. MIC90 values for norfloxacin were as follows:Citrobacter spp., 2μg/ml;Enterobacter spp., 0.13μg/ml;Escherichia coli, 0.06μg/ml;Klebsiella spp., 0.13μg/ml;Proteus spp., 0.06μg/ml;Salmonella spp., 1μg/ml;Serratia spp., 0.13μg/ml; andPseudomonas spp., 2μg/ml. MIC90 values for the other drugs were 4μg/ml or greater and many organisms were totally resistant to one or more of the other drugs (MIC > 128μg/ml). Cross resistance between norfloxacin and the related drugs nalidixic acid and cinoxacin was not observed.  相似文献   

10.
《Mucosal immunology》2015,8(4):896-905
Neutrophil elastase (NE) and cathepsin G (CG) contribute to intracellular microbial killing but, if left unchecked and released extracellularly, promote tissue damage. Conversely, mechanisms that constrain neutrophil serine protease activity protect against tissue damage but may have the untoward effect of disabling the microbial killing arsenal. The host elaborates thrombospondin-1 (TSP-1), a matricellular protein released during inflammation, but its role during neutrophil activation following microbial pathogen challenge remains uncertain. Mice deficient in TSP-1 (thbs1−/−) showed enhanced lung bacterial clearance, reduced splenic dissemination, and increased survival compared with wild-type (WT) controls during intrapulmonary Klebsiella pneumoniae infection. More effective pathogen containment was associated with reduced burden of inflammation in thbs1−/− mouse lungs compared with WT controls. Lung NE activity was increased in thbs1−/− mice following K. pneumoniae challenge, and thbs1−/− neutrophils showed enhanced intracellular microbial killing that was abrogated with recombinant TSP-1 administration or WT serum. Thbs1−/− neutrophils exhibited enhanced NE and CG enzymatic activity, and a peptide corresponding to amino-acid residues 793–801 within the type-III repeat domain of TSP-1 bridled neutrophil proteolytic function and microbial killing in vitro. Thus, TSP-1 restrains proteolytic action during neutrophilic inflammation elicited by K. pneumoniae, providing a mechanism that may regulate the microbial killing arsenal.  相似文献   

11.
Polychlorinated biphenyls (PCBs) are ubiquitous persistent organic pollutants that can be co-metabolically biotransformed by biphenyl-utilizing bacteria. In this study, terminal-restriction fragment length polymorphism (T-RFLP) was applied to the substrate specificity-determining region of the 2,3-biphenyl dioxygenase encoding genes of a microbial community found in a PCB-polluted soil. Notably, both the total biphenyl/PCB-utilizing community and its members actively expressing the 2,3-biphenyl dioxygenase gene were analyzed. T-RFLP fingerprinting along with gene library construction allowed us not only to detect biphenyl dioxygenases related to the well characterized catabolic patterns of Pseudomonas pseudoalcaligenes KF707 and Burkholderia xenovorans LB400, but also to reveal novel environmental enzyme classes displaying amino acid substitutions that may be related to broader specificity and improved catalytic properties. Furthermore, space and time of sampling along with bioavailability conditions of different PCBs were considered possible sources of profile variability.  相似文献   

12.
Sutures under selective host/environmental factors can potentiate postoperative surgical site infection (SSI). The present investigation characterized microbial recovery and biofilm formation from explanted absorbable (AB) and nonabsorbable (NAB) sutures from infected and noninfected sites. AB and NAB sutures were harvested from noninfected (70.9%) and infected (29.1%) sites in 158 patients. At explantation, devices were sonicated and processed for qualitative/quantitative bacteriology; selective sutures were processed for scanning electron microscopy (SEM). Bacteria were recovered from 85 (53.8%) explanted sites; 39 sites were noninfected, and 46 were infected. Suture recovery ranged from 11.1 to 574.6 days postinsertion. A significant difference in mean microbial recovery between noninfected (1.2 isolates) and infected (2.7 isolates) devices (P < 0.05) was noted. Staphylococcus epidermidis, Staphylococcus aureus, coagulase-negative staphylococci (CNS), Peptostreptococcus spp., Bacteroides fragilis, Escherichia coli, Enterococcus spp., Pseudomonas aeruginosa, and Serratia spp. were recovered from infected devices, while commensal skin flora was recovered from noninfected devices. No significant difference in quantitative microbial recovery between infected monofilament and multifilament sutures was noted. Biofilm was present in 100% and 66.6% of infected and noninfected devices, respectively (P < 0.042). We conclude that both monofilament and braided sutures provide a hospitable surface for microbial adherence: (i) a significant difference in microbial recovery from infected and noninfected sutures was noted, (ii) infected sutures harbored a mixed flora, including multidrug-resistant health care-associated pathogens, and (iii) a significant difference in the presence or absence of a biofilm in infected versus noninfected explanted devices was noted. Further studies to document the benefit of focused risk reduction strategies to minimize suture contamination and biofilm formation postimplantation are warranted.  相似文献   

13.
Soil Microbial Fuel Cells (MFCs) are devices that can generate electricity by using the flooded soil's anode respiring microbial consortium. When the MFC starts to work, the microbial community in the anode vicinity rapidly changes. This shift in the microbial community results in many dead cells that may release their DNA (relic DNA) and obscure culture independent estimates of microbial community composition. Although relic DNA is expected to increase in MFCs, the effect of relic DNA has not been investigated in the soil MFCs system. In this study the effect of the MFCs on the soil microbial community composition within the soil profile and the influence of relic DNA were investigated. Microbial community analysis revealed that the MFCs deployment significantly influenced the community composition within the soil profile. The phylum Proteobacteria (34.4% vs 23.6%) and the class Deltaproteobacteria (16.8% vs 5.9%) significantly increased in the MFCs compared to the control, while the phylum Firmicutes (24.0% vs 28.7%) and the class Sphingobacteria (5.3% vs 7.0%) were more abundant in the control. Furthermore, the archaeal phyla Euryarchaeota (40.7% vs 52.3%) and Bathyarchaeota (10.1% vs 17.3%) were significantly lower in the MFCs, whereas the phylum Woesearchaeota (DHVEG6) (24.4% vs 19.4%) was slightly enhanced. Moreover, the results showed that relic DNA can affect the relative abundance of Geobacter and Candidatus Methanoperedens, however, it has no significant effects on the microbial community structure. These results indicate that MFCs can influence the soil microbial community profile, nevertheless the relic DNA generated has minimum effect on the culture independent estimates of microbial community composition.  相似文献   

14.
PurposeMicrobial contamination of orthodox ophthalmic preparations poses a serious threat to the user by causing ocular infections. There is no such information about unorthodox ophthalmic preparations in a medical pluralistic system such as Ghana. The aim of this study was to assess unorthodox ophthalmic medications on the Ghanaian market for possible microbial contaminations.MethodsUnorthodox ophthalmic preparations were collected across different herbal and homeopathic outlets in Ghana. A total of 27 samples were collected from the ten (10) regions in Ghana. The samples were inoculated in different culture media (Plate count Agar, Blood Agar, MacConkey Agar, Saboraud Dextrose Agar). The microorganisms isolated were identified using standard microbiological procedures and antimicrobial susceptibility was done to determine whether they were resistant or susceptible strains.ResultsAll the samples were contaminated with bacteria and the majority were contaminated with fungus. A total of forty-eight bacteria spp. was isolated thus seven different types namely: Staphylococcus aureus, Bacilli spp., Serrati spp., Escherichia coli, Pseudomonas spp., Klebsiella spp. and Shigella spp. with Staphylococcus aureus being the predominant bacteria. For fungi, a total of eleven fungi species thus four different types namely: Cephalosporium spp., Penicillium spp., Cercosporium spp. and Clasdosporium spp. with the predominant fungi being Penicillium spp. Per the class of preparations, 15 contaminants were isolated from ten (10) anti-inflammatory preparations. The fungi were all susceptible to both Ketoconazole and Fluconazole but the bacteria were resistant to all the conventional antibiotics except Ciprofloxacin and Gentamycin.ConclusionUnorthodox ophthalmic preparations found on the Ghanaian market are contaminated with bacteria and fungi of clinical importance.  相似文献   

15.
《Research in microbiology》2014,165(7):517-525
The acidic peatlands of southern Brazil are essential for maintenance of the Atlantic Rain Forest, one of the 25 hot-spots of biodiversity in the world. While these ecosystems are closely linked to conservation issues, their microbial community ecology and composition remain unknown. In this work, histosol samples were collected from three acidic peatland regions during dry and rainy seasons and their chemical and microbial characteristics were evaluated. Culturing and culture-independent approaches based on SSU rRNA gene pyrosequencing were used to survey the bacterial community and to identify environmental factors affecting the biodiversity and microbial metabolic potential of the Brazilian peatlands. All acidic peatlands were dominated by the Acidobacteria phylum (56-22%) followed by Proteobacteria (28-12%). The OTU richness of these phyla and the abundance of their Gp1, Gp2, Gp3, Gp13, Rhodospirillales and Caulobacteriales members varied according to the period of collection and significantly correlated with the rainy season. However, despite changes in acidobacterial and proteobacterial communities, rainfall did not affect the microbial metabolic potential of the southern Brazilian Atlantic Rain Forest peatlands, as judged by the metabolic capabilities of the microbial community.  相似文献   

16.
Catheter-related bloodstream infection (CRBSI) is one of the most serious complications in hospitalised patients, leading to increased hospitalisation, intensive care admissions, extensive antibiotic treatment and mortality. A greater understanding of these bacterial infections is needed to improve the prevention and the management of CRBSIs. We describe here the systematic culture-independent evaluation of intravascular catheter (IVC) bacteriology. Twelve IVCs (6 central venous catheters and 6 arterial catheters) were collected from 6 patients. By using traditional culture methods, 3 patients were diagnosed with catheter colonisation including 1 patient who also had CRBSI, and 3 had no colonisation. From a total of 839,539 high-quality sequence reads from high-throughput sequencing, 8 microbial phyla and 76 diverse microbial genera were detected. All IVCs examined in this study were colonised with complex microbial communities including “non-colonised IVCs,” as defined using traditional culture methods. Two main community types were observed: Enterobacteriaceae spp., dominant in patients without colonisation or CRBSI; and Staphylococcus spp., dominant in patients with colonisation and CRBSI. More diverse pathogens and a higher microbial diversity were present in patients with IVC colonisation and CRBSI. Community composition did not appear to be affected by patients’ antibiotic treatment or IVC type. Characterisation of these communities is the first step in elucidating roles of these pathogens in disease progression, and to ultimately facilitate the improved prevention, refined diagnosis and management of CRBSI.  相似文献   

17.
BACKGROUND AND PURPOSE: Intensive agriculture is practised in Taiwan, and compost application is very popular as a means of improving the soil physical properties and supplying plant nutrition. We tested the potential of inoculation with thermotolerant microorganisms to shorten the maturity and improve the quality of biofertilizer prepared by composting. METHODS: Thermotolerant microorganisms were isolated from compost and reinoculated for the preparation of biofertilizer. The physical, chemical and biological properties of the biofertilizer were determined during composting. The effects of biofertilizer application on the growth and yield of rape were also studied. RESULTS: Among 3823 colonies of thermotolerant microorganisms, Streptomyces thermonitrificans NTU-88, Streptococcus sp. NTU-130 and Aspergillus fumigatus NTU-132 exhibited high growth rates and cellulolytic and proteolytic activities. When a mixture of rice straw and swine manure were inoculated with these isolates and composted for 61 days, substrate temperature increased initially and then decreased gradually during composting. Substrate pH increased from 7.3 to 8.5. Microbial inoculation enhanced the rate of maturity, and increased the content of ash and total and immobilized nitrogen, improved the germination rate of alfalfa seed, and decreased the content of total organic carbon and the carbon/nitrogen ratio. Biofertilizer application increased the growth and yield of rape. CONCLUSIONS: Inoculation of thermotolerant and thermophilic microorganisms to agricultural waste for biofertilizer preparation enhances the rate of maturity and improves the quality of the resulting biofertilizer. Inoculation of appropriate microorganisms in biofertilizer preparation might be usefully applied to agricultural situations.  相似文献   

18.
The incidence of skin and soft tissue infections (SSTIs) has increased dramatically over the past decade, resulting in significant morbidity in millions of otherwise healthy individuals worldwide. Certain groups, like military personnel, are at increased risk for SSTI development. Although nasal colonization with Staphylococcus aureus is an important risk factor for the development of SSTIs, it is not clear why some colonized individuals develop disease while others do not. Recent studies have revealed the importance of microbial diversity in human health. Therefore, we hypothesized that the nasal microbiome may provide valuable insight into SSTI development. To examine this hypothesis, we obtained anterior-naris samples from military trainees with cutaneous abscesses and from asymptomatic (non-SSTI) participants. We also obtained samples from within abscess cavities. Specimens were analyzed by culture, and the microbial community within each sample was characterized using a 16S sequencing-based approach. We collected specimens from 46 non-SSTI participants and from 40 participants with abscesses. We observed a significantly higher abundance of Proteobacteria in the anterior nares in non-SSTI participants (P < 0.0001) than in participants with abscesses. Additionally, we noted a significant inverse correlation between Corynebacterium spp. and S. aureus (P = 0.0001). The sensitivity of standard microbiological culture for abscesses was 71.4%. These data expand our knowledge of the complexity of the nasal and abscess microbiomes and potentially pave the way for novel therapeutic and prophylactic countermeasures against SSTI.  相似文献   

19.
Purpose: The present study was carried out to characterize the ESBL types and evaluated their in vitro activity against a collection of Gram negative bacteria (GNB) from a multicentric Indian surveillance study. Material and Methods: During January 2005 to June 2006, six tertiary care centres in India forwarded 778 non-duplicate GNB to our reference laboratory. Three hundred GNB from this collection were selected based on clinical significance and were used in the present study. Tested isolates included Escherichia coli (167), Klebsiella spp. (122) and Enterobacter spp. (11). ESBL screening and confirmation was performed for all the isolates. Minimum inhibitory concentration of imipenem, meropenem, ertapenem, levofloxacin, amikacin, piperacillin/tazobactam and ceftriaxone was determined by the E-test method. Molecular typing of the ESBLs was performed by polymerase chain reaction among the 121 selected isolates. Results: The study showed excellent susceptibility among the strains to imipenem (100%), meropenem (100%) and ertapenem (98.7%); good susceptibility to amikacin (89.7%) and piperacillin/tazobactam (85.3%) was observed. TEM and CTX-M were predominantly found in E. coli (39.2%) while, among the Klebsiella spp., TEM, SHV and CTX-M occurred together in 42.6% of the isolates. Conclusion: More than one ESBL was produced by many strains, and this was correlated with increased resistance levels. Carbapenems continue to show good in vitro activity and ertapenem is a potential alternative to imipenem and meropenem. Continued antimicrobial resistance surveillance is warranted in light of these findings.  相似文献   

20.
The ESwab collection device was compared to the collection swab provided as part of the Affirm VPIII microbial identification test kit for testing vaginal specimens with the Affirm test system. There was excellent agreement between the two sampling devices for Candida spp., Gardnerella vaginalis, and Trichomonas vaginalis.  相似文献   

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