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yeasts colonizing the leaf surfaces.the yeasts were isolated from the leaf surfaces of ten species of trees. the study site was a forest park (zelezná studnicka) of the small carpathians mountain range. one hundred and thirty seven yeast strains belonging to 13 genera were isolated from 320 samples of leaves and needles. seventeen yeast species were isolated, but only seven occurred regularly: aureobasidium pullulans, cryptococcus laurentii, pichia anomala, metschnikowia pulcherrima, saccharomyces sp., lachancea thermotolerans, an ...200717645279
effects of water-soluble low-molecular-weight beta-1, 3-d-glucan (branch beta-1, 6) isolated from aureobasidium pullulans 1a1 strain black yeast on restraint stress in mice.it is well known that different stress paradigms are able to rapidly induce corticosterone production and immune function through the activation of the hypothalamic-pituitary-adrenal axis. it has been reported that glucocorticoids suppress natural killer (nk) activity and interleukin (il)-1 production and, on the other hand, that il-1 and il-6 stimulate the release of corticotrophin-releasing-hormone from the rat hypothalamus. moreover, it has been reported that il-12 plays a central role in the ...200717725857
in vitro inhibition of postharvest pathogens of fruit and control of gray mold of strawberry and green mold of citrus by aureobasidin a.aureobasidin a (aba), an antifungal cyclic depsipeptide antibiotic produced by aureobasidium pullulans r106, has previously been shown to be effective against a wide range of fungi and protozoa. here we report the inhibitory effects of aba on spore germination, germ tuber elongation and hyphal growth of five pathogenic fungi including penicillium digitatum, p. italicum, p. expansum, botrytis cinerea and monilinia fructicola, which are major pathogens causing postharvest diseases of a variety of ...200717765990
aureobasidium pullulansas a biocontrol agent of blue mold in "rocha" pear.the blue mold of "rocha" pear caused by penicillium expansum is an important postharvest disease which is adequately controlled by application of synthetic fungicides. in recent years, strategies like biological control have been considered a desirable alternative to chemicals. several studies have demonstrated the potential of the yeast-like fungus aureobasidium pullulans for control of postharvest decay of pear. a portuguese isolate of aureobasidium pullulans was characterized and evaluated fo ...200617390846
biocontrol of blue mold on apple fruits by aureobasidium pullulans (strain ach 1-1): in vitro and in situ evidence for the possible involvement of competition for nutrients.aureobasidium pullulans strain ach1-1 was recently isolated for its biocontrol effectiveness against penicillium expansum, the causal agent of blue mold on harvested apples. in the present study, strain ach1-1 was found to be very effective in controlling p. expansum on apple wounds. for in vitro tests, strain ach1-1 and p. expansum were cocultured in the presence of apple juice (0 - 5%) using a system preventing direct contact between both agents. the presence of the antagonist greatly reduced ...200617390872
temporal changes in microscale colonization of the phylloplane by aureobasidium pullulans.colonization of apple leaves by the yeastlike fungus aureobasidium pullulans was followed quantitatively and spatially at a microscale level throughout two growing seasons. ten field leaves were sampled on 11 dates in 2003 and 15 dates in 2004. using an a. pullulans-specific fluorescence in situ hybridization probe and epifluorescence microscopy, we enumerated total cells, swollen-cells and chlamydospores (scc), and blastospores/mm(2) on leaf features, including the midvein, other (smaller) vein ...200616957250
multiple beta-fructofuranosidases by aureobasidium pullulans dsm2404 and their roles in fructooligosaccharide production.at least five types of beta-fructofuranosidases (ffases i, ii, iii, iv and v) were found in the cell wall of aureobasidium pullulans dsm2404 grown in a sucrose medium. the fungus first catalyzed the transfructosylation of sucrose, and produced fructooligosaccharide (fos) and glucose in the culture. fos was then consumed together with glucose, and finally fructose was produced. in the fos-producing period, the fungus expressed ffase i as a dominant ffase. however, in the fos-degrading period, the ...200617052265
fungal contamination of bedding.it is currently believed that most fungal exposure occurs external to the home.200616364170
subcutaneous mycosis produced by aureobasidium pullulans in a renal transplant recipient. 200616441646
nonribosomal peptide synthesis in schizosaccharomyces pombe and the architectures of ferrichrome-type siderophore synthetases in fungi.a nonribosomal peptide synthetase (nrps) in schizosaccharomyces pombe, which possesses an unusual structure incorporating three adenylation domains, six thiolation domains and six condensation domains, has been shown to produce the cyclohexapeptide siderophore ferrichrome. one of the adenylation domains is truncated and contains a distorted key motif. substrate-binding specificities of the remaining two domains were assigned by molecular modelling to glycine and to n-acetyl-n-hydroxy-l-ornithine ...200616502473
aureobasidium pullulans keratitis.corneal ulcer caused by aureobasidium pullulans is considered to be a rare entity. so far very few reports have appeared in the world literature and the authors' hospital is the first to report from nepal. although a. pullulans is regarded as a contaminant, it should be considered as a pathogen if isolated from corneal ulcer specimen with clinical signs of infection and with growth of the organism on two or more culture media or growth in one medium with consistent direct microscopy findings or ...200616671907
on the cover. aureobasidium pullulans. 200616729771
monitoring the formation of an aureobasidium pullulans biofilm in a bead-packed reactor via flow-weighted magnetic resonance imaging.the biofilm-forming fungus, aureobasidium pullulans dsm 2404, was grown in a bead-packed reactor. alterations within the reactor were analysed in several cross-sectional slices by magnetic resonance imaging (mri) with flow contrast. for the first time, biofilm accumulation could be continuously elucidated without using any contrast agents, and the non-stationary flow through the fixed-bed reactor could be visualized. the results indicate that the non-stationary flow through the biofilm reactor c ...200616802094
influence of starvation, surface attachment and biofilm growth on the biocide susceptibility of the biodeteriogenic yeast aureobasidium pullulans.to investigate the effect of starvation, surface attachment and growth in a biofilm on the susceptibility of aureobasidium pullulans to the biocides 2-n-octyl-4-isothiazolin-3-one (oit) and sodium hypochlorite (naocl).200616882139
continuous gluconic acid production by the yeast-like aureobasidium pullulans in a cascading operation of two bioreactors.the application of a new developed process for the continuous production of gluconic acid using a cascade of two bioreactors in a continuous process is shown reaching the highest concentration of gluconic acid described in the literature for continuous culture fermentation. very high gluconic acid concentrations of 272-308 g/l have been achieved under continuous cultivation of free-growing cells of aureobasidium pullulans in the first bioreactor at residence times (rt) between 19.5 and 24 h with ...200616906404
interactions between yeasts, fungicides and apple fruit russeting.the effect of inoculations with yeasts occurring on apple surfaces and fungicide treatments on the russeting of elstar apples was studied. captan, dithianon and a water treatment were implemented to study the interaction between the fungicides, the inoculated yeast species and aureobasidium pullulans, and the development of russet. all yeast inoculations aggravated russet, but rhodotorula glutinis, sporidiobolus pararoseus and a. pullulans did so to a greater extent than the other species. both ...200617156012
antitumor and antimetastatic activity of a novel water-soluble low molecular weight beta-1, 3-d-glucan (branch beta-1,6) isolated from aureobasidium pullulans 1a1 strain black yeast.though it has been reported that beta-glucans or protein-binding hetero-glucans isolated from mushrooms have antitumor activity, the antitumor and antimetastatic actions of purified, structurally defined polysaccharides (such as beta-glucans) have not been proven yet. a new low molecular weight (approximately 100 kda) beta-glucan was isolated from aureobasidium pullulans black yeast, and was found to have low viscosity and to be water-soluble. the industrial production of this p-glucan was achie ...200617201124
purification and properties of a family-10 xylanase from aureobasidium pullulans atcc 20524 and characterization of the encoding gene.an extracellular endo-1,4-beta-xylanase was purified from the culture supernatant of the ascomycete aureobasidium pullulans atcc 20524 grown on xylan. the purified enzyme was homogeneous as judged by sodium dodecyl sulphate-polyacrylamide gel electrophoresis and isoelectric focusing, which showed an apparent m (r) of 39 kda and a pi of 8.9, respectively. xylanase activity was optimal at ph 6.0 and 70 degrees c. the genomic dna and cdnas encoding this protein were cloned and sequenced. the xylana ...200615988573
identification and possible disease mechanisms of an under-recognized fungus, aureobasidium pullulans.investigations into the occurrence and health effects of yeast-like fungi in the outdoor air in the us have been limited. we sought to identify a respirable-sized fungus common in the pasadena air, locate a major source for the emissions and investigate its relevance to allergic disease.200616276113
characterization of microbial contamination in united states air force aviation fuel tanks.bacteria and fungi, isolated from united states air force (usaf) aviation fuel samples, were identified by gas chromatograph fatty acid methyl ester (gc-fame) profiling and 16s or 18s rrna gene sequencing. thirty-six samples from 11 geographically separated usaf bases were collected. at each base, an above-ground storage tank, a refueling truck, and an aircraft wing tank were sampled at the lowest sample point, or sump, to investigate microbial diversity and dispersion within the fuel distributi ...200616328508
inhibitory activity of phosphates on molds isolated from foods and food processing plants.six commercial phosphates were evaluated for inhibition of the growth of 17 molds isolated from food sources. the assays were performed at neutral and natural (without ph adjustment) ph values, and the molds were streaked on plate count agar with added phosphates. phosphate concentrations of 0.1, 0.3, 0.5, 1.0, and 1.5% (wt/vol) were used, and the mic was determined. the resistance of molds to phosphates depended on the species. at a neutral ph, aspergillus ochraceus and fusarium proliferatum we ...200516300093
integration of biocontrol agents and food-grade additives for enhancing protection of stored apples from penicillium expansum.forty-nine compounds currently used as additives in foods were tested in combination with three biocontrol agents, the yeasts rhodotorula glutinis, cryptococcus laurentii, and the yeastlike fungus aureobasidium pullulans, to increase their antagonistic activity against penicillium expansum, the causal agent of blue mold on apples. twelve additives dramatically improved the antagonistic activity of one or more of the tested biocontrol agents. in a two-way factorial experiment with these selected ...200516245713
use of xylanase and arabinofuranosidase for arabinose removal from unbleached kraft pulp.preparations of arabinofuranosidase and xylanase, respectively from aureobasidium pullulans and trichoderma longibrachiatum, were used to remove selectively xylose and arabinose from kraft pulp. the equilibrium moisture content of pulps treated with both enzymes, at varying relative humidities, revealed a consistently lower percent moisture content at all humidity set points. shorter fiber lengths indicated some deterioration when pulp was exposed to high concentrations of both enzymes.200516247673
the halophilic fungus hortaea werneckii and the halotolerant fungus aureobasidium pullulans maintain low intracellular cation concentrations in hypersaline environments.hortaea werneckii and aureobasidium pullulans, black yeast-like fungi isolated from hypersaline waters of salterns as their natural ecological niche, have been previously defined as halophilic and halotolerant microorganisms, respectively. in the present study we assessed their growth and determined the intracellular cation concentrations of salt-adapted and non-salt-adapted cells of both species at a wide range of salinities (0 to 25% nacl and 0 to 20% nacl, respectively). although 5% nacl impr ...200516269687
endophytic fungi associated with cacti in arizona.21 cactus species occurring in various localities within arizona were screened for the presence of fungal endophytes. 900 endophyte isolates belonging to 22 fungal species were isolated. cylindropuntia fulgida had the maximum endophyte species diversity, while c. ramosissima harboured the maximum number of endophyte isolates. alternaria sp., aureobasidium pullulans, and phoma spp. were isolated from several cactus species. the diversity of the endophyte assemblages was low and no host specificit ...200516018319
heat stable antimicrobial activity of allium ascalonicum against bacteria and fungi.to study antimicrobial activity of shallot in comparison with that of garlic and onion against 23 strains of fungi and bacteria, water extracts of garlic, shallot and onion bulbs were prepared. each extract was studied in different forms for their antimicrobial activity viz., fresh extract, dry extract and autoclaved extract. minimal inhibitory concentration and minimal lethal concentrations of these extracts were determined against all organisms by broth dilution susceptibility test. fresh extr ...200516121720
production of l-sorbitol from l-fructose by aureobasidium pullulans lp23 isolated from soy sauce mash.a strain lp23 that can convert l-fructose to l-sorbitol was isolated from soy sauce mash and identified as aureobasidium pullulans. the cells grown on l-arabinose were found to have relatively high l-fructose to l-sorbitol conversion potential. addition of erythritol to the reaction mixture considerably accelerated the conversion rate of l-fructose to l-sorbitol. during the conversion reaction, erythritol was added to the reaction mixture at 8-h intervals to maintain the concentration of erythri ...200516198270
adhesion of aureobasidium pullulans is controlled by uronic acid based polymers and pullulan.aureobasidium pullulans is a potentially pathogenic microfungus that produces and secretes the polysaccharide pullulan and other biomacromolecules, depending on the microbe's physiological state. the role of these macromolecules in mediating adhesion and attachment were examined. interfacial forces and adhesion affinities of a. pullulans were probed for early-exponential phase (eep) and late-exponential phase (lep) cells, using atomic force microscopy (afm). biochemical assays showed that a. pul ...200515762685
aureobasidium pullulans infection: fungemia in an infant and a review of human cases. 200515766608
purification and biochemical characterization of polygalacturonases produced by aureobasidium pullulans.the extracellular polygalacturonases produced by aureobasidium pullulans isolated from waters of the danube river were partially purified and characterized. the ph optima of polygalacturonases produced in the first phases of cultivation (48 h) and after 10 d as well as their optima of temperature, thermal stabilities, molecular masses, isoelectric points, action pattern and ability to cleave polymeric and oligomeric substrates were compared. polygalacturonases with a random action pattern (rando ...200515787251
process optimization of continuous gluconic acid fermentation by isolated yeast-like strains of aureobasidium pullulans.this study was focused on the optimization of a new fermentation process for continuous gluconic acid production by the isolated yeast-like strain aureobasidium pullulans dsm 7085 (isolate 70). operational fermentation parameters were optimized in chemostat cultures, using a defined glucose medium. different optima were found for growth and gluconic acid production for each set of operation parameters. highest productivity was recorded at ph values between 6.5 and 7.0 and temperatures between 29 ...200515937884
valinomycin affects the morphology of candida albicans.microbial metabolites were screened for inhibitors of hyphal growth in candida albicans. inhibitory activity was found among metabolites of a culture of an actinomycete, which had been isolated from soil. the active substance inhibited hyphal growth and induced growth as a chain of yeast cells under hyphal growth induction conditions. the active substance was purified and analyzed with 1h-nmr, 13c-nmr and mass spectra. the substance was identified as valinomycin, and commercial valinomycin inhib ...200516506692
aureobasidium pullulans morphology: two adapted polysaccharide stains.morphological stages of aureobasidium pullulans were investigated utilizing different media ingredients and were visualized by bright-field microscopy. a polysaccharide stain was developed to stain chlamydospores, cell walls, hyphae, and conidia, since current staining techniques do not reveal subcellular details to identify fungi, especially those that exhibit polysaccharide secretions.200516462864
extracellular cellulase production by tropical isolates of aureobasidium pullulans.cellulase production by aureobasidium pullulans from the temperate regions has remained speculative, with most studies reporting no activity at all. in the current study, tropical isolates from diverse sources were screened for cellulase production. isolates were grown on a synthetic medium containing cell walls of msasa tree (brachystegia sp.) as the sole carbon source, and their cellulolytic activities were measured using carboxymethyl cellulose and alpha-cellulose as substrates. all isolates ...200516391656
selection of antagonists of postharvest apple parasites: penicillium expansum and botrytis cinerea.the objectives of this study were to constitute a collection of pathogenic agents of economic importance which cause losses of apple fruits after harvest namely botrytis cinerea and penicillium expansum and to select in vivo efficient antagonistic strains able to protect fruits against both pathogens at 5 degrees c (p. expansum) and 25 degrees c (p. expansum & b. cinerea). twenty strains of p. expansum and ten strains of b. cinerea have been isolated from infected apple fruits. potential antagon ...200516637169
effect of the biocontrol yeast rhodotorula glutinis strain ls11 on patulin accumulation in stored apples.abstract contamination of apples (malus domestica) and derived juices with fungicide residues and patulin produced by penicillium expansum are major issues of food safety. biocontrol agents represent an alternative or supplement to chemicals for disease control. our data show that these microbes could also contribute to actively decreasing patulin accumulation in apples. three biocontrol agents, rhodotorula glutinis ls11, cryptococcus laurentii ls28, and aureobasidium pullulans ls30, were examin ...200518943357
application and evaluation of denaturing gradient gel electrophoresis to analyse the yeast ecology of wine grapes.the performance of denaturing gradient gel electrophoresis (dgge) for analysing yeasts associated with wine grapes was compared with cultural isolation on malt extract agar (mea). after optimisation of pcr and electrophoretic conditions, the lower limit of yeast detection by pcr-dgge was 10(2) cfuml(-1), although this value was affected by culture age and the relative populations of the species in mixed culture. in mixed yeast populations, pcr-dgge detected species present at 10-100-fold less th ...200415450194
in situ quantification of biocide efficacy using gfp transformed aureobasidium pullulans.to develop a real-time in situ method to quantify loss of viability of aureobasidium pullulans prafs8 cells attached to plasticized polyvinyl chloride (ppvc) with incorporated biocides, and to use the method to compare biocide efficacy in situ.200415546403
characteristics of neutralization of acids by newly isolated fungal cells.soil microorganisms play an important role in maintaining soil ph at levels suitable for other soil organisms. to clarify the biological neutralization mechanism in soil, we isolated soil microorganisms showing a high ability to neutralize acids and studied their characteristics. from our taxonomic study, three isolated strains were identified as filamentous fungi, namely mucor sp., aspergillus fumigatus, and aureobasidium pullulans. these strains could secrete basic materials, such as ammonia, ...200416233589
acidophilic xylanase from aureobasidium pullulans: efficient expression and secretion in pichia pastoris and mutational analysis.a yeast-like fungus aureobasidium pullulans var. melanigenum strain atcc 20524 produces an extracellular acidophilic endo-1,4-beta-xylanase with an optimum ph of 2.0 [ohta et al., j. biosci. bioeng., 92, 262-270 (2001)]. the xyni cdna encoding the precursor protein (xyni) was expressed in the methylotrophic yeast pichia pastoris under the control of the alcohol oxidase i gene promoter. the 34 amino acid prepro-signal peptide of the a. pullulans xyni directed the efficient secretion of 178 mg of ...200416233716
theoretical correlation between viscosities at dynamic and steady flow states in aureobasidium pullulans culture fluids.for the culture fluid and exopolysaccharide solution of the fungus aureobasidium pullulans in a previous study, the angular frequency dependence of dynamic viscosity is well superimposed on the shear rate dependence of steady flow viscosity. for various polymeric fluids, the superimposition of the dependencies of steady flow viscosity and dynamic viscosity has also been realized. in this study, it is derived that, by assuming the sinusoidal oscillating flow of a viscoelastic fluid, complex visco ...200416233744
novel method for cell immobilization and its application for production of oligosaccharides from sucrose.the purpose of the present investigation was to develop a novel method for cell immobilization.200414746552
production of fructo-oligosaccharides from molasses by aureobasidium pullulans cells.three different strains of aureobasidium pullulans were grown in batch cultures to compare their abilities for the production of fructo-oligosaccharides. specific intracellular enzyme activity was the highest with strain kccm 12017 and enzyme production was closely coupled to growth. using a. pullulans cells, 166 g/l fructo-oligosaccharides was produced from 360 g/l molasses sugar as sucrose equivalent at 55 degrees c and ph 5.5 after 24 h incubation.200414987721
the synergistic effects of stochasticity and dispersal on population densities.using laboratory experiments, simulation models, and analytical techniques, we examined the impact of dispersal on the mean densities of patchily distributed populations. even when dispersal leads to no net additions or removals of individuals from a population, it may nonetheless increase mean population densities if the net immigration rate is positive when populations are growing and negative when they are declining. as a model system for exploring this phenomenon, we used the yeastlike fungu ...200415026974
which morphological forms of the fungus aureobasidium pullulans are responsible for pullulan production?attempts were made to clarify the precise location and possible site of production of the alpha-glucan pullulan in different morphological forms of the fungus aureobasidium pullulans. gold-conjugated pullulanase was used as the specific probe for this purpose. no cell wall pullulan-like material was detected by transmission electron microscopy (tem) in any morphological form of this fungus, although intracellular electron transparent material bound this probe. when silver enhancement of this gol ...200415033243
salt-induced changes in lipid composition and membrane fluidity of halophilic yeast-like melanized fungi.the halophilic melanized yeast-like fungi hortaea werneckii, phaeotheca triangularis, and the halotolerant aureobasidium pullulans, isolated from salterns as their natural environment, were grown at different nacl concentrations and their membrane lipid composition and fluidity were examined. among sterols, besides ergosterol, which was the predominant one, 23 additional sterols were identified. their total content did not change consistently or significantly in response to raised nacl concentra ...200415064990
physical and chemical aspects of long-term biodeterioration of some polymers and composites.a biodeterioration study was performed on synthetic polymeric materials including homogenous film made from poly(tetrafluorine ethylene), copolymer film made from tetrafluorine ethylene and perfluoromethyl vinyl ether, vulcanized rubber containing natural caoutchouc, and vulcanized rubber, the main component of which was synthetic butadiene nitrile caoutchouc. the materials were exposed for 12 years to the open air, in mycological containers, and in a cellar in maritime climate conditions: air h ...200415269902
ferric reductase, superoxide dismutase and alkaline phosphatase activities in siderophore producing fungi.enzymes associated with release of iron from internalized ferrated siderophore (ferrisiderophore reductase), with damage to the cell at high iron concentration (superoxide dismutase) and siderophore synthesis (alkaline phosphatase), were examined in 3 test fungi viz., aspergillus sp. abp4, aureobasidium pullulans and rhizopus sp. extracellular ferrisiderophore reductase activity was present in all the three fungi, but aureobasidium pullulans, that showed the highest activity (84.3 microm min(-1) ...200415282958
production of high molecular weight pullulan by aureobasidium pullulans hp-2001 with soybean pomace as a nitrogen source.the production of pullulan by aureobasidium pullulans hp-2001 was enhanced by yeast extract as a nitrogen source as well as soybean pomace. the highest production of pullulan by a. pullulans hp-2001 with yeast extract was 5.5 g/l whereas that of pullulan with soybean pomace was 7.5 g/l. the gas chromatogram of pullulan produced by a. pullulans hp-2001 with soybean pomace as a nitrogen source showed that the major and minor components were glucose and mannose. the ftir spectra of pullulans produc ...200415288272
pullulan is a slowly digested carbohydrate in humans.pullulan is an extracellular polysaccharide excreted by the fungus aureobasidium pullulans. to evaluate the glycemic and breath hydrogen responses and gastrointestinal tolerance to pullulan, nondiabetic healthy adult subjects (n = 28) were studied in a randomized, double-masked, crossover design. after an overnight fast, subjects consumed beverages containing 50 g of carbohydrate from either maltodextrin (control) or pullulan. capillary blood glucose response was determined for 180 min postprand ...200312672917
mould specific igg antibodies connected with sinusitis in teachers of mould damaged school: a two-year follow-up study.the aim of this study was to describe the relationship between mould exposure induced by moisture damage and mould specific immunoglobulin g antibodies to 20 common mould species and their association with respiratory diseases.200314587535
concentration and species diversity of airborne fungi near busy streets in lithuanian urban areas.the investigations on air pollution in industrial cities of lithuania: vilnius, alytus, kaunas, marijampole and elektrenai were aimed at detecting the presence of fungi and aerosol particles during different seasons of the year. sampling of fungal spores was carried out at 20 sampling sites. active air sampling was performed simultaneously with the use of passive sedimentation plates. data on the spread of various micromycete species in the air of cities contaminated with various pollutants are ...200314677918
characterization of aureobasidium pullulans isolated from airborne spores in thailand.isolates from air in several locations in thailand were identified as aureobasidium pullulans pr with dark pigmentation (loei province), a. pullulans su with an unusual conidial apparatus (chiangmai province), and a. pullulans cu with burgundy-red pigmentation (from a shady area in bangkok). the internal transcribed spacer sequences of the rdna of a. pullulans su and a. pullulans cu confirmed that they were a. pullulans. both a. pullulans cu and a. pullulans pr preferred 30 degrees c and ph 7.5 ...200312612782
a prospective trial of fungal colonization after laser resurfacing of the face: correlation between culture positivity and symptoms of pruritus.after full-face laser resurfacing of the face, patients often complain of pruritus, which may be intense. it has been suggested that some cases of postresurfacing pruritus may be associated with subclinical fungal infection.200312614419
continuous gluconic acid production by isolated yeast-like mould strains of aureobasidium pullulans.by extensive microbial screening, about 50 strains with the ability to secrete gluconic acid were isolated from wild flowers. the strains belong to the yeast-like mould aureobasidium pullulans (de bary) arnaud. in shake flask experiments, gluconic acid concentrations between 23 and 140 g/l were produced within 2 days using a mineral medium. in batch experiments, various important fermentation parameters influencing gluconic acid production by a. pullulans isolate 70 (dsm 7085) were identified. c ...200312655452
analysis of microtubules and f-actin structures in hyphae and conidia development of the opportunistic human pathogenic black yeast aureobasidium pullulans.organization of the cytoskeleton was studied in the ascomycetous black yeast aureobasidium pullulans, an opportunistic human pathogen, in an effort to present it as a potential target of antifungal therapy. long cytoplasmic microtubules, extending along the hyphae from the base to the growing apex, were the dominant structures in multinucleate interphase cells. before mitosis these microtubules disappeared and were replaced by intranuclear spindles. this reorganization of microtubules occurred a ...200312686629
fungus propagules in plastids: the mycosome hypothesis.a stress-induced "mycosome" phase of aureobasidium pullulans consisting of minute reproductive propagules that may revert directly to walled yeast cells is described. mycosomes detected by light- and electron-microscopy reproduce within senescent plant plastids, and display three developmental pathways: wall-less cells (protoplasts), yeast cells, or membrane-bounded spherules that harbor plastids. widespread in plant and algal cells, mycosomes are produced by both ascomycete and basidiomycete fu ...200312730709
comparative studies of fungal degradation of single or mixed bioaccessible reactive azo dyes.a screening using several fungi (phanerochaete chrysosporium, pleurotus ostreatus, trametes versicolor and aureobasidium pullulans) was performed on the degradation of syringol derivatives of azo dyes possessing either carboxylic or sulphonic groups, under optimized conditions previously established by us. t. versicolor showed the best biodegradation performance and its potential was confirmed by the degradation of differently substituted fungal bioaccessible dyes. enzymatic assays (lignin perox ...200312781230
yeast interactions and wine flavour.wine is the product of complex interactions between fungi, yeasts and bacteria that commence in the vineyard and continue throughout the fermentation process until packaging. although grape cultivar and cultivation provide the foundations of wine flavour, microorganisms, especially yeasts, impact on the subtlety and individuality of the flavour response. consequently, it is important to identify and understand the ecological interactions that occur between the different microbial groups, species ...200312892919
single-leaf resolution of the temporal population dynamics of aureobasidium pullulans on apple leaves.the abundance of phylloplane microorganisms typically varies over several orders of magnitude among leaves sampled concurrently. because the methods traditionally used to sample leaves are destructive, it has remained unclear whether this high variability is due to fixed differences in habitat quality among leaves or to asynchronous temporal variation in the microbial population density on individual leaves. we developed a novel semidestructive assay to repeatedly sample the same apple leaves fr ...200312902284
[survivability of some black yeast-like fungal species under uv-irradiation].the survival of 4 species (14 strains) of black-pigmented yeast-like fungi, isolated from radioactive polluted ecotopes, after uv-irradiation has been studied. their survival was different in the limits of 3 orders from 0.7 to 0.0001% and was described by the exponential composite exponential and composite sigmoid types of dose curves. essential heterogeneity for the level and character of survival after uv-irradiation of conidia aureobasidium pullulans, hormonema dematioides, exophiala cf. jean ...200312945195
purification and properties of a feruloyl esterase involved in lignocellulose degradation by aureobasidium pullulans.the lignocellulolytic fungus aureobasidium pullulans nrrl y 2311-1 produces feruloyl esterase activity when grown on birchwood xylan. feruloyl esterase was purified from culture supernatant by ultrafiltration and anion-exchange, hydrophobic interaction, and gel filtration chromatography. the pure enzyme is a monomer with an estimated molecular mass of 210 kda in both native and denatured forms and has an apparent degree of glycosylation of 48%. the enzyme has a pi of 6.5, and maximum activity is ...200312957952
disseminated nosocomial fungal infection by aureobasidium pullulans var. melanigenum: a case report.we report on a rare case of disseminated nosocomial fungal infection due to aureobasidium pullulans var. melanigenum in a severely traumatized patient. repeated blood and urine cultures yielded multicellular filamentous hyphal structures of varying size accompanied by budding yeast-like-cells of ellipsoidal morphology. the patient became asymptomatic after fluconazole therapy.200312958301
fungal biodiversity--as found in nasal mucus.the biodiversity of fungi isolated from the nasal mucus of patients suffering from chronic rhinosinusitis and from healthy persons was monitored over 28 months. mucus samples were obtained by flushing the noses of patients with saline or by endoscopic sinus surgery. fungi from mucus were cultivated on agar plates. identification was performed microscopically and by polymerase chain reaction with subsequent sequencing of the ribosomal internal transcribed spacer region. altogether, 619 strains of ...200312964848
a modified model for non-newtonian viscosity behavior of aureobasidium pullulans culture fluid.the culture fluid of the fungus aureobasidium pullulans and the exopolysaccharide solution obtained by removal of the microbial cells exhibit a marked shear dependence of viscosity. the viscosity in a high shear rate region was a little higher than that predicted by a non-newtonian viscosity equation derived previously on the basis of the concept of traveling force. in a sample exhibiting such high shear rate dependence, a hydrodynamic effect based on the fluid structure of the binding of contac ...200316233455
characteristic behavior of viscosity and viscoelasticity of aureobasidium pullulans culture fluid.measurements of dynamic viscoelasticity and steady flow viscosity were made for culture fluids obtained by cultivation of aureobasidium pullulans iam 5060 with initial phs of 6 and 7 and for exopolysaccharide (eps) solutions obtained by removal of microbial cells. the molecular weight of eps of the ph 6 culture is about 850,000, and that of the ph 7 culture is much larger. in the present study, the complex viscosity shifted to a considerably larger value than that of the steady flow viscosity. t ...200216233223
[isolation from the environment of strains of microorganisms with glucose oxidase activity].strains of microorganisms (13) producing enzyme glucoseoxidase were isolated from various samples of soil. the ability to oxidase glucose in presence of oxygen is most expressed in representatives of genera aureobasidium, aspergillus, penicillium. media containing the kj-starch indicator were used at primary step for isolation of microorganisms from the environment. the strain, identified as aureobasidium pullulans (de bary) arnaud, isolated from soil had the greatest glucoseoxidase activity, re ...200212664547
antimicrobial activity of berberine--a constituent of mahonia aquifolium.the antimicrobial activity of the protoberberine alkaloid, berberine, isolated from mahonia aquifolium, was evaluated against 17 microorganisms including two gram-negative bacteria--pseudomonas aeruginosa and escherichia coli (both resistant and sensitive), two gram-positive bacteria--bacillus subtilis and staphylococcus aureus, zoogloea ramigera, six filamentous fungi--penicilium chrysogenum, aspergillus niger, aureobasidium pullulans (black and white strain), trichoderma viride (original green ...200212422513
diversity of microfungi in the phylloplane of plants growing in a mediterranean ecosystem.mediterranean ecosystems have not been investigated as natural habitats for microorganisms in general, and microfungi in particular. plants harvested in "serra da arrábida" (38 degrees 27' n, 9 degrees 02' w), a mediterranean ecosystem in portugal, were analyzed for the filamentous microfungi inhabiting their surface. two field locations with distinct climatic characteristics were studied: 'fonte do veado' (38 degrees 28'50" n, 9 degrees 0'17" w; 300 m elevation) located on the northern slope, a ...200212442302
extracellular enzymatic activity profiles in yeast and yeast-like strains isolated from tropical environments.the objective of this study was to investigate the extracellular enzymatic activity (eea) profile of yeasts isolated from tropical environments of the brazilian rain forest. this screening survey could constitute the first approach in selecting yeast strains of environmental origin potentially exploitable as enzyme producers.200212452958
continuous production of high-content fructooligosaccharides by a complex cell system.a complex biocatalyst system with a bioreactor equipped with a microfiltration (mf) module was employed to produce high-content fructooligosaccharides (fos) in a continuous process initiated by a batch process. the system used mycelia of aspergillus japonicus ccrc 93007 or aureobasidium pullulans atcc 9348 with beta-fructofuranosidase activity and gluconobacter oxydans atcc 23771 with glucose dehydrogenase activity. calcium carbonate slurry was used to control ph to 5.5, and gluconic acid in the ...200212467463
flow field-flow fractionation and characterization of ionic and neutral polysaccharides of vegetable and microbial origin.the flow field-flow fractionation (flfff) analysis of a variety of neutral as well as ionic polysaccharides from plants and micro-organisms shows the generally broad distribution in molecular size of these polymers. this result is also obtained on a commercial sample of pullulan whose size distribution appears much wider than that of any of five standard fractions of the same polymer. clear evidence of some physico-chemical properties of the polysaccharides is given by the study of the effect of ...200212685569
imaging microscopic viscosity with confocal scanning optical tweezers.the techniques of confocal microscopy and optical tweezers have shown themselves to be powerful tools in biological and medical research. we combine these methods to develop a minimally invasive instrument that is capable of making hydrodynamic measurements more rapidly than is possible with other devices. this result leads to the possibility of making scanning images of the viscosity distribution of materials around biopolymer-producing cells. 100 x 100 images can be taken with 0.5-microm spati ...200218007774
hybrid model building methodology using unsupervised fuzzy clustering and supervised neural networks.this paper suggests a model building methodology for dealing with new processes. the methodology, called hybrid fuzzy neural networks (hfnn), combines unsupervised fuzzy clustering and supervised neural networks in order to create simple and flexible models. fuzzy clustering was used to define relevant domains on the input space. then, sets of multilayer perceptrons (mlp) were trained (one for each domain) to map input-output relations, creating, in the process, a set of specified sub-models. th ...200211787014
production and characterization of pullulan from beet molasses using a nonpigmented strain of aureobasidium pullulans in batch culture.the production of pullulan from beet molasses by a pigment-free strain of aztreobasidium pullulans on shake-flask culture was investigated. combined pretreatment of molasses with sulfuric acid and activated carbon to remove potential fermentation inhibitors present in molasses resulted in a maximum pullulan concentration of 24 g/l, a biomass dry wt of 14 g/l, a pullulan yield of 52.5%, and a sugar utilization of 92% with optimum fermentation conditions (initial sugar concentration of 50 g/l and ...200211900113
a new pullulan and a branched (1-->3)-, (1-->6)-linked beta-glucan from the lichenised ascomycete teloschistes flavicans.the polysaccharides formed on hot alkaline extraction of the ascomycetous lichen teloschistes flavicans were fractionated to give two glucans, which were characterised by methylation analysis and 1d and 2d nmr spectroscopy. one was a branched beta-glucan containing (1-->3) and (1-->6) linkages, a structure which is more typical of basidiomycetes rather than ascomycetes, which have linear glucans. the other was an alpha-glucan with alternating (1-->4) and (1-->6) linkages, found for the first tim ...200212023070
optimization of high molecular weight pullulan production by aureobasidium pullulans in batch fermentations.of five strains of aureobasidium pullulans studied, nrrl y-2311-1 yielded the highest titer (26.2 g/l) of pullulan and formed the lowest amount of melanin-like pigment. sucrose was superior to glucose as the carbon and energy source on the basis of yield and titer of pullulan produced. pullulan titer was higher (26.2 vs 5.1 g/l), biomass concentration was lower (6.9 vs 12.7 g/l), and do was lower (0 vs 60% of saturation) when the fermenter was agitated by a marine propeller compared to rushton i ...200212052094
monitoring and control of pullulan production using vision sensor.the production of the polysaccharide pullulan by the yeast-like fungi, aureobasidium pullulans, is accompained by cellular morphogenetic changes. high productivity and yield of the process have been found to correlate with high concentration of yeast-like cells in the culture. the morphogenetic changes of a. pullulans cells depend on the culture conditions, e.g., dissolved oxygen, shear rate and medium composition. in order to improve the productivity of the process, a novel control law was form ...200212088884
new exopolysaccharides produced by aureobasidium pullulans grown on glucosamine.the polysaccharides produced by aureobasidium pullulans, grown using glucosamine as the carbon source, were investigated by means of methylation analysis, affinity chromatography and nmr spectroscopy. the results indicated that, besides a small amount of pullulan, this micro-organism was capable of producing-in low yields-mixtures of at least two different complex polysaccharides containing mainly mannose and galactose. (1)h nmr spectra of two fractions obtained by lectin affinity chromatography ...200212110195
population biology of aureobasidium pullulans on apple leaf surfaces.colonization of apple leaves by the yeast-like fungus aureobasidium pullulans was studied in the field on eight dates over 2 years. population densities from adaxial leaf surfaces were approximately log10 0.5-2.6 u higher when enumerated directly along line transects as microscopic counts of a. pullulans cells specifically identified by fluorescence in situ hybridization (fish) than indirectly as cfu obtained by plating leaf washings from comparable surfaces onto nutrient media. site-specific ma ...200212166677
[comparative analysis of radial linear growth velocity of micromycetes isolated from different ecotopes].the work aim was the discovering of peculiarities of microscopic fungi responding to radioactive pollution by growth velocity change. the linear growth velocity of a broad range of micromycetes was analyzed. they were chosen in such a way that every species, as far as possible, was presented by the strains isolated from radioactive polluted and clean regions. most of the studied species were characterized by the absence of reliable growth velocity differences of strains of the same species growi ...200212190032
an analysis of trehalose, glycerol, and mannitol accumulation during heat and salt stress in a salt marsh isolate of aureobasidium pullulans.polyhydroxy compounds from aureobasidium pullulans exposed to stress treatments of heat, salt, and simultaneous heat and salt were isolated, identified, and quantified. results from both thin-layer chromatography (tlc) and high performance liquid chromatography (hplc) showed that concentrations of trehalose, mannitol, and glycerol increased under stress conditions that induce osmotic- and thermotolerance in a. pullulans. the cellular concentration of trehalose increased in heat-stressed and in s ...200221156509
screening of micro-organisms for decolorization of melanins produced by bluestain fungi.a total of 17 fungi and four bacteria were screened for their ability to decolorize melanin, using isolated extracellular melanin of the bluestain fungus aureobasidium pullulans as substrate. on agar media, decolorization was observed by four fungal strains: bjerkandera adusta vtt-d-99746, galactomyces geotrichum vtt-d-84228, trametes hirsuta vtt-d-95443 and trametes versicolor vtt-d-99747. the four fungi were more efficient on nitrogen-limited medium than on complete medium. the melanin-decolor ...200111330716
inhibition effect of initial pb2+ concentration on pb2+ accumulation by saccharomyces cerevisiae and aureobasidium pullulans.pb2+ accumulation by saccharomyces cerevisiae and aureobasidium pullulans was inhibited by the initial pb2+ concentration. in the case of s. cerevisiae, as initial pb2+ concentrations increased, the accumulated pb2+ per unit cell dry weight at equilibrium and the time required to reach an equilibrium state increased at low initial pb2+ concentration. on the contrary, the accumulated pb2+ decreased at high initial pb2+ concentration at all ph values. the inhibition effect of initial pb2+ concentr ...200111396916
glutathione metabolism and dimorphism in aureobasidium pullulans.yeast<-->mycelium morphological transitions of aureobasidium pullulans are influenced by numerous environmental factors. in general, changes in the glutathione (gsh) metabolism of dimorphic fungi may lead to alterations in the reduced thiol status of the cells that are hypothesised to initialise morphological transitions. in accordance with this hypothesis, the specific gsh levels found in a. pullulans yeast cells were always significantly higher than those in mycelia. one the other hand, there ...200111441460
polysaccharide production by a reduced pigmentation mutant of aureobasidium pullulans nys-1.to isolate a reduced pigmentation mutant of aureobasidium pullulans nys-1 and characterize its cellular pigmentation plus its polysaccharide and biomass production relative to carbon source.200111472528
polysaccharide production by immobilized aureobasidium pullulans cells in batch bioreactors.cells of the fungus aureobasidium pullulans atcc 201253 were entrapped within 4% agar cubes or 5% calcium alginate beads and were examined for their production of the polysaccharide pullulan in batch bioreactors. the batch bioreactors were utilized twice for 168 hours of polysaccharide production in medium containing corn syrup as a carbon source. the agar-entrapped cells produced nearly equivalent pullulan concentrations during both production cycles. the alginate-entrapped cells produced highe ...200111716217
green fluorescent protein as a novel indicator of antimicrobial susceptibility in aureobasidium pullulans.presently there is no method available that allows noninvasive and real-time monitoring of fungal susceptibility to antimicrobial compounds. the green fluorescent protein (gfp) of the jellyfish aequoria victoria was tested as a potential reporter molecule for this purpose. aureobasidium pullulans was transformed to express cytosolic gfp using the vector ptefegfp (a. j. vanden wymelenberg, d. cullen, r. n. spear, b. schoenike, and j. h. andrews, biotechniques 23:686-690, 1997). the transformed st ...200111722914
aureobasidium pullulans scleritis following keratoplasty: a case report.fungal scleritis is a rare entity. a 50-year-old patient with culture proven aureobasidium pullulans corneal ulcer underwent therapeutic keratoplasty. he developed scleritis 5 days following surgery. although the patient had symptomatic improvement after antifungal therapy, surgical debridement, and cryotherapy, visual improvement was only marginal. aureobasidium pullulans should be looked for as a cause for keratomycosis and scleromycosis, especially in tropical countries.200111725774
[effect of enhanced uv-b radiation on chemical composition, fungal colonization and decomposition of spring wheat plant].under uv-b radiation, the cho (soluble carbohydrate) concentration in leaves decreased significantly, while the concentrations of hcel (holocellulose) and protein in leaves and that of hcel in stems increased significantly. hcel concentration in roots did not change significantly. under uv-b radiation, the colonization rates of penicillium ochro-chloron and aspergillus niger on leaves and stems increased significantly during growing phase, those of trichoderma koningii and aureobasidium pullulan ...200111757366
ergosterol biosynthesis in novel melanized fungi from hypersaline environments.halotolerant and halophilic melanized fungi were recently described in hypersaline waters. a close study of the sterol composition of such fungi, namely hortaea werneckii, alternaria alternata, cladosporium sphaerospermum, cladosporium sp., and aureobasidium pullulans revealed the dominance of ergosterol and the presence of 29 intermediates of its biosynthesis pathway. the presence or absence of intermediates from distinct synthesis routes gave insight into the operative synthetic pathways from ...200111254746
purification and characterization of an acidophilic xylanase from aureobasidium pullulans var. melanigenum and sequence analysis of the encoding gene.an extracellular endo-1,4-beta-xylanase was purified from the culture supernatant of aureobasidium pullulans var. melanigenum (atcc 20524) grown on oat-spelt xylan. the purified enzyme showed a single band on sds-polyacrylamide gel electrophoresis with an apparent m(r) of 24 kda and had an isoelectric point of 6.7. xylanase activity was optimal at ph 2.0 and 50 degrees c. the genomic dna and cdnas encoding this protein were cloned and sequenced. southern blot analysis indicated that the xylanase ...200116233094
fluid viscosity of aureobasidium pullulans cultures obtained at two different initial ph values.aureobasidium pullulans iam 5060 grown in media with initial phs of 6 and 7 differed in its production of exopolysaccharides (eps). under the latter condition, eps of a high molecular weight was produced in an especially large amount. the viscosity of the culture broths and the eps solutions obtained by removing the microbial cells exhibited a marked non-newtonian and complex behavior depending on the measurement method. the nature of the viscosity of the fluids is explained by means of several ...200016232739
polysaccharide hydrolases of aureobasidium pullulans.the polysaccharide hydrolase activity of a group of selected strains of the genus aureobasidium pullulans was investigated using a new gel testing assay. a total of 31 strains were tested for alpha-amylase, alpha-glucosidase and glucoamylase, beta-glucosidase, lichenase, cellulase, xylanase and xylosidase, mannanase and mannosidase production during growth of microorganisms on respective meshed polysaccharide gels. attempts were made to increase the polysaccharide hydrolase activity through sele ...200011271822
bird keeper's lung without bird keepingethe identification of disease inducing allergens in hypersensitivity pneumonitis can be very problematic, and only by a thorough analysis of anamnestic data the source of allergen can be identified. we report a case of a 32-year-old female diagnosed with hypersensitivity pneumonitis caused by the inhalation of budgerigar antigen in her home. she had been living there for two years and had never been a bird keeper at all. the former proprietor of the house was a budgerigar keeper for years. when ...200010756167
molecular analysis of the aureobasidium pullulans ura3 gene encoding orotidine-5'-phosphate decarboxylase and isolation of mutants defective in this gene.orotidine-5'-phosphate decarboxylase (omp decarboxylase) catalyses the final step in the pyrimidine biosynthesis, the conversion of orotidine-5'-phosphate (omp) to uridine-5'-phosphate. the ura3 gene of aureobasidium pullulans. encoding omp decarboxylase, was isolated from an aureobasidium genomic library constructed in the plasmid pblueskriptsk-. the ura3 gene of a. pullulans has an open reading frame of 271 amino acid residues. analysis of the sequence revealed the presence of two introns. in ...200010772469
hypersaline waters in salterns - natural ecological niches for halophilic black yeasts.hypersaline waters in salterns have so far been considered to be populated only with halophilic algae and bacteria and completely lacking halophilic fungi. in this paper we present population dynamics of polymorphic black yeasts, isolated from hypersaline waters (3-30% nacl) of a saltern, in relation to different physicochemical parameters. hortaea werneckii, phaeotheca triangularis, trimmatostroma salinum, aureobasidium pullulans and cladosporium spp. were detected with the highest frequency ju ...200010858582
relationships between activities of xylanases and xylan structures.structures of five water-soluble xylans have been determined. four purified xylanase enzymes have been studied for the hydrolysis of the xylans. different xylanases have different activities against various xylan structures. the key factors that influence the rate of xylan hydrolysis are chain length and degree of substitution. two family 11 xylanases, orpinomyces pc2 xylanase and trichoderma longibrachiatum xylanase, can rapidly hydrolyze xylans that have a chain length greater than 8 xylose re ...200010862906
fungal colonization and biodeterioration of plasticized polyvinyl chloride.significant substratum damage can occur when plasticized pvc (ppvc) is colonized by microorganisms. we investigated microbial colonization of ppvc in an in situ, longitudinal study. pieces of ppvc containing the plasticizers dioctyl phthalate and dioctyl adipate (doa) were exposed to the atmosphere for up to 2 years. fungal and bacterial populations were quantified, and colonizing fungi were identified by rrna gene sequencing and morphological characteristics. aureobasidium pullulans was the pri ...200010919769
[effect of nitrogen sources on biosynthesis, chemical composition, and structure of exopolysaccharides from aureobasidium pullulans (de bary) arnaud].the effect of the nitrogen source and the c/n ratio of the growth medium on the biosynthesis, composition, and structure of the exopolysaccharides (epss) of aurebasidium pullulans (de bary) arnaud var. aubasidani yurlova var. nov. and a. pullulans var. pullulans was studied. a. pullulans var. pullulans and a. pullulans var. aubasidani strains synthesized the maximum amounts of epss in the presence of, respectively, a reduced nitrogen source ((nh4)2so4) and an oxidized nitrogen source (nano3) in ...200011008689
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