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1.
The fungal and bacterial flora of the leaf surfaces of five plants growing in Egypt were studied. The fungal flora showed seasonal fluctuations with at least one peak. Twenty three genera with fifty three species were found,Aspergillus andPenicillium being most common. Other fungi showed variable percentages of the total count. Nitrogen-fixing bacteria were not isolated from the phyllosphere of the five plant species. Micrococci were most predominant among the epiphytic bacteria. Spore-forming bacteria and actinomycetes were less frequent on the leaf surfaces of the associated plants.  相似文献   

2.
The microorganisms associated with the undiseased human colon wall were examined in material obtained from four sudden-death victims. In traffic accident subjects (aged 45 and 16 years) the anaerobe-aerobe ratio was about 104:1 in all areas of the colon examined, whereas in acute heart failure subjects (aged 74 and 46 years) the ratio was as low as 1.2:1. The flora of each individual was distinct and complex. Although the predominant anaerobes isolated were Bacteroides and Fusobacterium spp., which composed over 50% of the flora in some samples, the species isolated (indicated by morphology and glucose fermentation products) varied between individuals. Other major types observed were gram-positive nonsporing rods, including Bifidobacterium spp., and anaerobic cocci (between 8 and 20% of isolates). Clostridia were only isolated in significant numbers from one individual. Scanning electron microscopy showed that most of the organisms were present below the top surface of the mucin layer overlying the mucosa. The use of several different preparative procedures for microscopy showed a complex microbial structure within the mucus, but major variations in the bacterial populations in different areas of the colon were not found. Spiral-shaped organisms up to 60 μm long in the form of double helices were found in two subjects by scanning electron microscopy but were not isolated during the parallel bacteriological investigation. The differences between this and previous studies are discussed in relation to experimental procedures and also in contrast to results with animals that showed a particularly specialized flora associated with the colon wall.  相似文献   

3.
A comparative study of the occurrence of culturable airborne fungi was carried out during the four seasons of the year in four social welfare homes (SWHs), one in each of the cities of Cracow (Małopolskie province) and Białystok (Podlaskie province) and the villages of Karniowice and Czerewki situated approximately 20 km from the two cities respectively. Air of randomly chosen rooms and bathrooms, corridors, ward kitchens, soiled-linen closets, dining rooms, day rooms and nurses’ stations was sampled using single-stage impactor samplers and isolated moulds and yeasts were identified by macroscopic, microscopic and biochemical characteristics. Generally the greatest numbers of fungi were observed in the autumn. Penicillium and Cladosporium were isolated from the air in all four SWHs during all seasons of the year, but a wider range of other taxa were isolated from those in Małopolskie province.  相似文献   

4.
The mold flora of certain frozen pastries and chicken pies was investigated. Molds were determined qualitatively or quantitatively, or both, by preparing pour plates of the blended product and incubating the plates at various temperatures. The mesophilic fungal flora developed on plates incubated at 10 and 20 C, whereas psychrophilic fungi were obtained on plates incubated at 0 and 5 C. About 2,000 cultures of fungi, representing about 100 different species, were isolated from various products. Four different brands of blueberry, two brands of cherry pastries, two brands of apple, and one brand of raspberry pastries were examined. In addition, two brands of chicken pies were studied. Blueberry pastries had a much higher total fungal population than the other products, although different brands of blueberry pastries varied considerably. Blueberry pastries had from 347 to 1,586 psychrophilic fungi per g. Cherry pastries had about 70 to 110 psychrophiles per g, and apple pastries had 19 to 92 psychrophiles per g. Chicken pies contained very few psychrophilic fungi, about 15 per g. Aureobasidium pullulans was recovered most frequently. About 90% of the psychrophilic fungi found in blueberry products was A. pullulans. Depending upon the brand of cherry pastry, either Phoma spp. or A. pullulans was the most common fungus present. Apple pastries also displayed brand variation, but were unique in having many mesophilic aspergilli. This genus was generally absent from other products. The Penicillium content of apple pastries was also rather high; 50% of the psychrophilic flora was represented by this genus. The psychrophilic fungal flora of chicken pies was composed primarily of penicillia (50%) and Chrysosporium pannorum (46%).  相似文献   

5.
The process of mating reaction of Saccharomyces cerevisiae was studied by electron microscopy. Prior to the dissolution of the part of the cell walls separating the conjugating pair of cells, the thinning of the electron transparent layer of the cell wall occurs at the part toward which the nuclei are migrating. After the dissolution of the cell walls of the conjugating cells, the cell membranes become associated with each other, then to be broken and rejoined. The first diploid bud emerges from about the middle of the zygote. The morphological changes during the mating reaction are discussed in relation to the biochemical changes so far known.  相似文献   

6.
7.
The population of the microbial flora of a mixed blue gramma grass (Bouteloua gracilis H. B. K.) and prickly pear (Opuntia polyacantha Haw.) prairie near Amarillo, Texas, was studied during 1971 after a severe drought. Bacteria, fungi, and algae were estimated by plate count and terminal dilution procedures. Rates of grass and paper decomposition were determined. The microbial flora of soil associated with bovine-grazed grass did not differ significantly from the flora associated with ungrazed grass, either qualitatively or quantitatively. During drought, a greater number of fungi were found in soil associated with prickly pear than in that associated with blue gramma grass. The microbial biomass decreased one full log between the surface and a depth of 50 cm, and the percentage of anaerobes increased with depth. The maximum numbers of fungi and algae detected were 8 × 105 and 6 × 104/g respectively. A linear relationship existed between the microbial biomass and soil moisture. The maximum number of aerobic, heterotrophic bacteria detected was 1.5 × 108 viable cells per g of soil.  相似文献   

8.
A saprophytic bacterial flora is present on the penis and the distal part of the urethra of stallions. Little is known about the fungal flora of their reproductive tract. As micro organisms play an important role in mares fertility, the aim of the study was to describe the distribution of fungi and bacteria in the normal genital apparatus of stallions. The microbic flora of the reproductive tract of 11 healthy, fertile stallions was evaluated, collecting samples from 5 different locations: urethral fossa, penis/internal lamina of the prepuce, urethra pre- and post-ejaculation, and semen. For fungal examination samples were taken on 3 different occasions (N = 165), while for bacteriologic examination samples were taken on one occasion only (N = 55). There was a statistical difference in the presence of filamentous fungi between urethral fossa or penis/prepuce (45.4%) and urethra pre- or postejaculation or semen (15.1%, 6.0%, and 0.0%, respectively). Yeasts were isolated in 9.1% of the samples, never in semen. The most represented mycelial fungi were Penicillium spp., Aspergillus spp., Scopulariopsis spp., Trichosporon spp. and Mucoracee. The proportion of samples showing a total bacterial count ≥10 000 colony forming units (CFU) was higher for urethral fossa than for urethra pre- or postejaculation or for semen. Some bacterial growth was always observed in all locations, including the ejaculate. Differences between sampling locations were observed also for Staphylococci, both coagulase positive and negative. Salmonella enterica Abortus equi and sulphite reducing clostridia and other pathogens (including Klebsiella spp. and Pseudomonas spp.) were never isolated. Escherichia coli and coliforms always showed a low or absent flora. These data add information to the literature.  相似文献   

9.
A strain of Byssochlamys nivea, isolated from altered heat processed strawberries, produces an antibiotic substance which is efficient against several species of gram (-) bacteria and a few species of gram (+). This substance is completely ineffectual on Mycobacteria and fungi (yeasts or moulds) at the concentration used.  相似文献   

10.
Systemic mycoses in killer whales (Orcinus orca) are rare diseases, but have been reported. Two killer whales died by fungal infections at the Port of Nagoya Public Aquarium in Japan. In this study, the fungal flora of the pool environment at the aquarium was characterized. Alternaria spp., Aspergillus spp. (A. fumigatus, A. niger, A. versicolor), Fusarium spp. and Penicillium spp. were isolated from the air and the pool surroundings. The other isolates were identified as fungal species non-pathogenic for mammals. However, the species of fungi isolated from the environmental samples in this study were not the same as those isolated from the cases of disease in killer whales previously reported.  相似文献   

11.
Recurrent vaginal candidiasis (RVC) is considered to be a hypersensitivity disorder that is associated with allergic rhinitis (AR) in immune deficiencies; however, whether or not the composition of the vaginal fungal flora in patients with AR and RVC is altered and if such alterations in patients with AR are associated with the development of RVC remain unclear. In the present study, a cultivation-independent method with the 18S rRNA gene clone library was used to analyze the diversity and composition of the vaginal fungal flora in patients with AR and RVC and to explore the association. Three fungal phyla (Ascomycotae, 22 out of 28; Basidiomycetes, 5 out of 28; and Oomycetes, 1 out of 28) were identified from groups of healthy volunteers, patients with AR, patients with RVC, and patients with RVC complicated by AR, including 28 phylotypes of fungal flora (10, 15, 17, and 21 phylotypes for each group, respectively). The predominant genera of fungi identified in the vagina included Candida, uncultured fungi, and Dothideomycetes. An increased proportion of Candida albicans accompanied with decreased proportions of Saccharomyces cerevisiae and uncultured fungi was observed in patients with AR or RVC (P?<?0.05). Candida glabrata, Eladia saccula, Trichosporon jirovecii, and Phytophthora spp. occurred simultaneously in the three patient groups. The composition of the fungal communities in the four groups was statistically different (P?<?0.001). The vaginal fungal diversity in patients with AR or RVC was significantly higher compared with healthy volunteers (P?<?0.05). The data revealed an increased diversity and varied composition of the vaginal fungal flora in patients with AR and RVC and indicated that disturbed vaginal fungal flora in patients with AR might be correlated with disease progression in patients with RVC.  相似文献   

12.
In the present study, a well-defined lichen community was screened for associated fungi for the first time. The photophilous lichen community Letharietum vulpinae was chosen because its character species, Letharia vulpina, was expected to host rather specialized fungi due to the presence of antimycotic secondary compounds. A considerable number of the associated fungi that were isolated were probably selective for lichens, because they appeared to be distantly related to fungi known from other substrates. The majority of these obligatory, lichen-associated fungi were only isolated in the course of the present study and represent hitherto unknown phylogenetic lineages. Parts of the lichen-associated fungi overlapped those colonizing rock surfaces or were closely related to endophytic fungi, but the lichen-associated and endophytic fungi still represented separate lineages.  相似文献   

13.
Cell walls from the crayfish parasite Aphanomyces astaci strongly enhanced phenol oxidase activity in crayfish blood or cell-free serum. The activation was not very specific since bacteria, cells, and cell walls of some algae, fungi, and higher plants also activated the enzyme strongly. Only cell walls from one fungus lacked this property. Laminaran, a purified glucan found in many plant cell walls, activated the enzyme as well, but cellulose, chitin, or nylon did not. On the other hand, attachment of the enzyme to the wall surfaces and subsequent strong local melanization was much more specific and occurred only on a few fungi but not on other plant cell walls, bacteria, or other solid, enzyme-activating or nonactivating material. The mechanism of activation and attachment is discussed.  相似文献   

14.
During dismantling and relocation of the Takamatsuzuka Tumulus stone chamber, many Cladophialophora and chaetothyrialean black fungi, such as Exophiala and Phialophora, were isolated from samples taken from the joints between the stone walls. However, inside the stone chamber of the Kitora Tumulus, after intermittent UV irradiation in 2009, these black fungi were also isolated from samples taken from the stone walls. Molecular phylogenetic analyses based on only nrLSU and the concatenated (nrLSU D1/D2 + ITS) sequences revealed that the 35 Takamatsuzuka and Kitora Tumuli isolates of Cladophialophora and the chaetothyrialean black fungi were divergent. Two new species of Cladophialophora are described herein: C. tumulicola from the viscous gels and various substrates on the stone walls of the Takamatsuzuka and Kitora Tumuli and C. tumbae from black substances on the plastic cover over the “thief hole,” soil and plaster pieces between the stone walls, and the exterior of the Takamatsuzuka Tumulus chamber. Also, molecular phylogenetic placements for the remaining eight Takamatsuzuka and Kitora Tumuli isolates of chaetothyrialean black fungi have been determined or suggested.  相似文献   

15.
《Mycoscience》2014,55(3):168-176
We isolated filamentous fungi from soil samples of peat layers in Aomori and Oita Prefectures in Japan and Perth and Kinross district in Scotland by a serial dilution plate technique. The mycobiota in each peat soil showed some common and characteristic features. The abundance of fungal isolates (CFU/g) from peat soil was low: about 1/3 to 1/30 compared with evergreen or coniferous forests or cultivated soil. Trichoderma or Mucorales species were scarcely observed; these fungi occupied only 3% of the total number of colonies. On the other hand, fungi such as Conioscypha and Tolypocladium that are normally isolated rather rarely were encountered at a comparatively high rate. Acremonium guillematii and Tolypocladium cylindrosporum were recorded for the first time in Japan. Sterile fungi occupied 50% of the total number of isolates. The low abundance of fast-growing fungi enabled us to pick slow-growing fungi up easily from the isolation medium. It is interesting that species not previously described in Japan, or scarcely reported, were isolated commonly from both Japanese and Scottish samples. A peat soil sample is therefore an attractive source of untapped microbial resources.  相似文献   

16.
Environmental fungi, moulds and yeasts could reach the nasal cavity with the inhaled air causing respiratory symptoms in atopic subjects, but little is known about the fungal flora of this site. In the present study samples of the nasal cavities of 135 subjects aged 18-35 years (48 allergic patients to fungi, mites and/or cat fur and from 87 normal subjects--healthy, control group) were cultured. All of them lived in the metropolitan area of Barcelona. Fungi were isolated from 41.5% of healthy people and in 14.8% of allergy patients (p = 0.011). Morphologically, 50.4% of the isolates were located within 4 genera: Cladosporium, Penicillium, Aspergillus and Alternaria, fungi which are considered the most allergenic. The most prevalent species were: Cladosporium herbarum and C. cladosporioides (23.6%). Alternaria alternata was isolated only in 8.8% of samples from the allergic group, although most subjects were sensitive to this species. There were not differences in the isolation rate between genera and smoking-no-smoking groups. The lower prevalence of nasal fungi from allergic patients could be related to the nasal insufficiency, the hypersecretion and the larger use of handkerchiefs.  相似文献   

17.
M. A. Line 《Plant and Soil》1990,125(1):149-152
Nitrogen-fixing enterobacteria (Enterobacter agglomerans and Citrobacter freundii) were commonly found associated with the microflora of stained Sassafras (Atherosperma moschatum Labill.) in forests of SE Tasmania. However, their populations never exceeded 3× 104 cells g−1 dry wood and comprised at most 3% of the total bacterial flora. Bacterial colonization of the wood appeared to coincide with that by non-hymenocetous fungi: bacteria were never isolated in significant numbers from wood not infected with fungi. The contribution of the N2-fixing flora to the N economy of the habitat is considered to be negligible.  相似文献   

18.
An elicitor of glyceollin accumulation in soybeans (Glycine max L.) has been isolated from a commercially available extract of brewers' yeast. Yeast is not a known pathogen of plants. The elicitor was isolated by precipitation in 80% (v/v) ethanol followed by column chromatography on DEAE-cellulose, sulfopropyl-Sephadex, and concanavalin A-Sepharose. Compositional and structural analysis showed the elicitor to be a glucan containing terminal, 3-, 6-, and 3,6-linked glucosyl residues. The yeast elicitor stimulates the accumulation of glyceollin in the cotyledons and hypocotyls of soybeans when as little as 15 nanograms or 100 nanograms of the elicitor is applied to the respective tissues. The yeast elicitor is very similar in both structure and absolute elicitor activity to an elicitor isolated from the mycelial walls of Phytophthora megasperma var. sojae, a pathogen of soybeans. These and other results of this laboratory suggest that plants are able to respond to the presence of a wide range of fungi by recognizing, as foreign to the plant, structural polysaccharides of the mycelial walls of the fungi.  相似文献   

19.
Abstract:Lichen communities were examined on 62 churches in Mecklenburg-Vorpommern, Germany. Ninety-six lichen species and subspecies, and three species of lichenicolous fungi were identified. Tylothallia biformigera and Lecanora campestris subsp. dolomitica are reported as new to Germany, and another 20 species are considered as threatened. This implies that the stone walls of churches represent an extremely important habitat in Mecklenburg-Vorpommern, where natural rock outcrops are rare. The distribution of lichen species was analyzed quantitatively in relation to several habitat factors. Aspect, substratum and inclination were found to be important factors for 35, 34 and 31 species, respectively. The height of the relevé was a significant factor for many species. Twenty-three species, which are described in the literature with oceanic to suboceanic distributions, occur significantly more frequently near the coast. The ways in which microclimate affects each of these habitat factors and contributes to the presence or absence of a species or group of species are discussed. Some species have narrow and specific habitat demands, whereas others thrive under a wide range of environmental conditions. The advantages of a strictly schematic approach with a detailed statistical analysis are discussed.  相似文献   

20.
A preliminary survey of water systems in hospitals and hotels showed that Legionella pneumophila may be found in water storage and distribution systems as well as in the recirculating cooling water of air-conditioning plants. Altogether 42 isolates of L pneumophila were made from 31 establishments, six of which were associated with cases of legionnaires'' disease but in 25 of which there was no known association with disease. In the six establishments implicated epidemiologically as the source of legionnaires'' disease, these organisms were found in each of their water-distribution systems and also in the cooling water from each of the three with cooling towers. In establishments not associated with cases, water from three out of nine cooling towers, four out of 24 taps or showers, and one out of 15 storage tanks was found to contain legionellae. The organisms were isolated by guinea-pig inoculation and subsequent culture of their peritoneal fluid, liver, and spleen. Finding L pneumophila in water systems in the absence of cases of legionnaires'' disease should not at present be an indication for attempts at eradication.  相似文献   

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