The ability of filamentous fungi to produce acids on indoor building materials

Sixty two filamentous fungi isolated from paint coatings, wallpaper, carton-gypsum board, and indoor air in buildings were screened for acid activity. It was found that 64.5% of strains produce acids on medium with bromo-cresol purple, where 18% of the strains were distinguished by very high acid activity (acid activity coefficient Q = 1.32–2.83), including the species:Aspergillus niger, Aspergillus versicolor, Penicillium expansum, Penicillium brevicom pactum, Penicillium chrysogenum, Cladosporium cladosporioides, Stachybotrys chartarum, Mucor globosus, Ulocladium chartarum andAlternaria alternata. Research indicated that filamentous fungi considerably decrease the pH of the medium when that medium containing building material. The greatest acid production and pH decrease of the medium was observed during the growth of filamentous fungi in a medium with mortar, while the production of acids was less in a medium with cartongypsum board, gypsum, and wallpaper. Filamentous fungi produced succinic, oxalic, malic and fumaric acids in the medium with indoor building materials. It was stated that the type of building material affects the spectrum and quantity of organic acids produced by filamentous fungi.     

Mites and fungi in heavily infested stores in the Czech Republic

Toxigenic and allergen-producing fungi represent a serious hazard to human food and animal feed safety. Ninety-four fungal species were isolated from mite-infested samples of seeds taken from Czech seed stores. Fungi were isolated from the surface of four kinds of seeds (wheat, poppy, lettuce, and mustard) and from the gut and external surface of five species of mites (i.e., Acarus siro L., 1758, Caloglyphus rhizoglyphoides (Zachvatkin, 1973), Lepidoglyphus destructor (Schrank, 1781), Tyrophagus putrescentnae (Schrank, 1781) and Cheyletus malaccensis Oudemans 1903) separately. Multivariate analysis of fungi complex composition showed that the frequency of fungal was species significantly influenced by the kind of seed. Fungal frequencies differed between mites gut and exoskeleton surface and between the surfaces of mites and seeds. Three groups of fungal species were recognized: 1) mite surface-associated fungi: Penicillium brevicompactum, Alternaria alternata, and Aspergillus versicolor; 2) mite surface- and seed-associated fungi: Aspergillus niger, Penicillium crustosum, Penicillium aurantiogriseum, Penicillium chrysogenum, and Aspergillus flavus; and 3) seed-associated fungi: Cladosporium herbarum, Mucor dimorphosporus f. dimorphosporus, Botrytis cinerea, Penicillium griseofulvum, and Eurotium repens. Mite-carried species of microfungi are known to produce serious mycotoxins (e.g., aflatoxin B1, cyclopiazonic acid, sterigmatocystin, ochratoxin A, and nephrotoxic glycopeptides) as well as allergen producers (e.g., A. alternata and P. brevicompactum). Storage mites may play an important role in the spread of some medically hazardous micromycetes. In addition, these mite-fungi associations may heighten the risk of occurrence of mycotoxins in food and feed stuffs and cause mixed contamination by fungal and mite allergens.     

Identification of volatile markers for indoor fungal growth and chemotaxonomic classification of Aspergillus species

Microbial volatile organic compounds (MVOCs) were collected in water-damaged buildings to evaluate their use as possible indicators of indoor fungal growth. Fungal species isolated from contaminated buildings were screened for MVOC production on malt extract agar by means of headspace solid-phase microextraction followed by gas chromatography-mass spectrometry (GC-MS) analysis. Some sesquiterpenes, specifically derived from fungal growth, were detected in the sampled environments and the corresponding fungal producers were identified. Statistical analysis of the detected MVOC profiles allowed the identification of species-specific MVOCs or MVOC patterns for Aspergillus versicolor group, Aspergillus ustus, and Eurotium amstelodami. In addition, Chaetomium spp. and Epicoccum spp. were clearly differentiated by their volatile production from a group of 76 fungal strains belonging to different genera. These results are useful in the chemotaxonomic discrimination of fungal species, in aid to the classical morphological and molecular identification techniques.     

Keratinophilic fungi and other moulds associated with air-dust particles from Egypt

One-hundred and eleven species and three species varieties belonging to 39 genera were collected from 50 dust samples on the five media used at 28°C. Using the hair-baiting technique with horse hair, 10 species ofChrysosporium were isolated:C. asperatum, C. state ofArthroderma tuberculatum, C. indicum, C. inops, C. keratinophilum, C. merdarium, C. pannorum, C. queenslandicum, C. tropicum andC. xerophilum. True dermatophytes were isolated:Trichophyton verrucosum andTrichophyton sp. Also, numerous fungi tolerating high levels of cycloheximide were encountered, such as members ofAcremonium, Aspergillus andPenicillium. On plates of glucose or cellulose Czapek-Dox agar (free from sucrose) the most frequent fungi were:Alternaria alternata, Aspergillus flavus, A. flavus var.columnaris, A. fumigatus, A. niger, A. ochraceus, A. sydowii, A. terreus, Chaetomium globosum, Cladosporium herbarum, Emericella nidulans, Fusarium oxysporum, Mucor hiemalis, Penicillium chrysogenum, P. oxalicum, Scopulariopsis brevicaulis andUlocladium atrum. On plates of 50% sucrose or 10 and 20% NaCl-Czapek's agar, some interesting species were frequently encountered:Eurotium amstelodami, E. chevalieri, E. halophilicum, E. montevidensis, E. repens, E. rubrum andScopulariopsis halophilica. The isolated, fungi have been tested for osmophilicity and halophilicity, they showed different rates of growth on sucrose and sodium chloride-Czapek's medium of various osmotic potential.     

Antifungal activity of thyme (Thymus vulgaris L.) essential oil and thymol against moulds from damp dwellings

AIMS: To characterize antifungal activities of essential oil of thyme (Thymus vulgaris L.) and pure thymol, as comparative substance, on different mould species isolated from damp dwellings. METHODS AND RESULTS: Fifty samples of wall scrapes were collected from damp dwellings in Zagreb, the capital of Croatia. The members of the following mould genera were recovered from the samples: Aspergillus (44%), Penicillium (18%) Alternaria, Ulocladium, Absidia and Mucor (8%) Cladosporium, Trichoderma and Rhizopus (6%), and Chaetomium (2%). Two strains of Stachybotrys chartarum were isolated from damp dwellings in Slovakia. Antifungal activities of the thyme essential oil, which contains p-cymene (36.5%), thymol (33.0%) and 1,8-cineole (11.3%) as main components, and pure thymol were determined by the dilution method and exposure to vaporous phase of the oil. Minimum inhibitory concentrations (MIC) of both thymol and essential oil were bellow 20 microg ml(-1), except for Mucor spp. (50.20 microg ml(-1)). Thymol exhibited approximately three-times stronger inhibition than essential oil of thyme. The vaporous phase of the thyme essential oil (82 microg l(-1)) in glass chambers strongly suppressed the sporulation of moulds during 60 days of exposure. CONCLUSION: The thyme essential oil possesses a wide range spectrum of fungicidal activity. The vaporous phase of the oil exhibited long-lasting suppressive activity on moulds from damp dwellings. SIGNIFICANCE AND IMPACT OF THE STUDY: Essential oil of thyme and thymol could be used for disinfection of mouldy walls in the dwellings in low concentration.     

广东湛江湾可培养丝状真菌分布状况的初步调查

通过一次航行对广东湛江湾19个站位的表层和底层海水进行采样。经过对样品的分离纯化,共获得253株丝状真菌菌株。通过测序获得了121个rDNA-ITS序列,并已提交给GenBank。经统计分析发现,湛江湾表层和底层海水真菌数量总体上表现为由湾内向湾口逐渐减少的水平分布格局;湛江湾表层丝状真菌的数量略多于底层,在海水表层和底层中真菌种类和数量的分布规律相似。根据形态特征及rDNA-ITS的Blast同源性分析,这些菌株分属于18个属和32个分类单元,其中包括7个海洋真菌新记录属。结果表明,湛江湾丝状真菌多样性Shannon指数达2.75,物种优势度变化范围为30.90%–0.02%。枝孢属Cladosporium的优势度最高,为湛江湾优势种群,其次是青霉属Penicillium、侧齿霉属Engyodontium、曲霉属Aspergillus、枝顶孢属Acremonium等。湛江湾表层和底层海水真菌群落的Jaccard相似系数为0.42。     

Mycotic flora in the lower digestive tract of feral pigeons (Columba livia) in the El Paso, Texas area.

Fourteen species of fungus were isolated from the lower digestive tract of 39 of 80 pigeons. Sixteen pigeons had concurrent isolations while two harbored three species. Fungi isolated were Allescheria boydii, Aspergillus spp., Candida krusei, Chrysosporium spp., Geotrichum candidum, Mucor spp., Paeciliomyces spp., Penicillium spp., Rhizopus spp., Rhodotorula spp., Scopulariopsis spp., Streptomyces spp., and Trichosporon cutaneum. There was no apparent evidence that these fungi were associated with clinical disease in any of the pigeons.     

南极淡水分离出的菌物

本文报道从南极乔治王岛所采11个水样中分离出的菌物98株,初步鉴定出17属21种,其中6属(Acremonium,Arthrinium,Gliocladium,Phoma,Scopulariopsis,Ulocladium)13种为南极新记录,后者是:桃色顶孢Acremonium persicinum(Nicot)W.Gams,密顶孢A.strictum W.Gams,构巢曲霉Aspergillus nidulans(Eidam)Winter,聚多曲霉Asp.sydowii(Bainier & Sart)Thom & Church,芽枝状枝孢Cladosporium cladosporioides(Fries)de Vries,长孢被孢霉Mortierella elongata Linnemann,桔灰青霉Penicillium aurantiogriseum Dierckx,平滑青霉Pen.glabrum(Wehmer)Westling,鲜绿青霉Pen.viridicatum Westling,白瓶霉Phialophora alba v.Beyma,帚状瓶霉Ph.fastigiata(Lagerberg & Melin)Conant,纸状葡萄穗霉Stachybotrys chartarum(Ehrenberg ex Link)Hughes,和葡萄状单隔霉Ulocladium botrytis Preuss。温度试验表明:这些菌虽多为世界广布种,但已适应南极地区寒冷的气候。     

遗址木构件有害真菌的快速测定方法

介绍了1种快速测定遗址木构件有害真菌的方法:用孢子菌丝悬浮液直接接种于供试木块上,培养4d,即可确定其侵染性;培养8d,即可确定其侵染力。应用该方法成功地测定了灰绿曲霉(Aspergillus glau-cus)、黑曲霉(Aspergillus niger)、枝孢霉(Cladosporiumsp.)、顶青霉(Penicillium corylophilum)、柑桔青霉(Penicilliumcitrinum)、团青霉(Penicillium commune)、黄曲霉(Aspergillus flavus)、微紫青霉(Penicilliumjanthinellum)、总状毛霉(Mucor racemosus)、绿木霉(Trichoderma viride)等10种真菌的侵染性和侵染力。     

Characterization of airborne molds, endotoxins, and glucans in homes in New Orleans after Hurricanes Katrina and Rita

In August and September 2005, Hurricanes Katrina and Rita caused breeches in the New Orleans, LA, levee system, resulting in catastrophic flooding. The city remained flooded for several weeks, leading to extraordinary mold growth in homes. To characterize the potential risks of mold exposures, we measured airborne molds and markers of molds and bacteria in New Orleans area homes. In October 2005, we collected air samples from 5 mildly water-damaged houses, 15 moderately to heavily water-damaged houses, and 11 outdoor locations. The air filters were analyzed for culturable fungi, spores, (1-->3,1-->6)-beta-D-glucans, and endotoxins. Culturable fungi were significantly higher in the moderately/heavily water-damaged houses (geometric mean=67,000 CFU/m3) than in the mildly water-damaged houses (geometric mean=3,700 CFU/m3) (P=0.02). The predominant molds found were Aspergillus niger, Penicillium spp., Trichoderma, and Paecilomyces. The indoor and outdoor geometric means for endotoxins were 22.3 endotoxin units (EU)/m3 and 10.5 EU/m3, respectively, and for (1-->3,1-->6)-beta-D-glucans were 1.7 microg/m3 and 0.9 microg/m3, respectively. In the moderately/heavily water-damaged houses, the geometric means were 31.3 EU/m3 for endotoxins and 1.8 microg/m3 for (1-->3,1-->6)-beta-D-glucans. Molds, endotoxins, and fungal glucans were detected in the environment after Hurricanes Katrina and Rita in New Orleans at concentrations that have been associated with health effects. The species and concentrations were different from those previously reported for non-water-damaged buildings in the southeastern United States.     

Marine fungi in sediments of the Sea of Japan (Russian territory) and their biologically active metabolites

The most abundant marine fungi encountered in various regions of the Sea of Japan belong to the genera Penicillium, Aspergillus, Wardomyces, Trichoderma, Chrysosporium, and Chaetomium. Facultative marine fungi of the genera Scytalidium, Verticillium, and Oidiodendron and obligate marine fungi of the genus Dendryphiella are much less abundant. The composition of marine sediments and the anthropogenic load on them were found to influence the abundance and species diversity of fungi, as well as the occurrence of fungal strains producing hemolytically active substances. The biodiversity of mycobiota and the abundance of hemotoxin-producing fungi in marine sediments may be used to evaluate the anthropogenic load on marine biocenoses. Hemolytic compounds were produced by 57% of the fungi isolated from marine sediments. The hemolytic activity of Chaetomium spiculipilium was revealed in the fraction of the culture liquid containing extracellular fatty acids and pigments. The fatty acid composition of this marine fungus was determined.     

Production of mycotoxins on artificially and naturally infested building materials

In this study, the ability to produce mycotoxins during growth on artificially infested building materials was investigated for Penicillium chrysogenum, Pen. polonicum, Pen. brevicompactum, Chaetomium spp., Aspergillus ustus, Asp. niger, Ulocladium spp., Alternaria spp., and Paecilomyces spp., all isolated from water-damaged building materials. Spores from the different isolates of the above mentioned species were inoculated on gypsum board with and without wallpaper and on chipboard with and without wallpaper. Fungal material was scraped off the materials, extracted, and analyzed using high performance liquid chromatography-diode array detection and thin layer chromatography. All six isolates of C. globosum produced the toxic chaetoglobosins A and C, at levels of up to 50 and 7 g/cm² respectively. The quantities of secondary metabolites produced by Penicillia were generally low, and no toxin production was detected from any of the five isolates of Pen. chrysogenum. Both isolates of Pen. polonicum produced 3-methoxy-viridicatin, verrucosidin, and verrucofortine. Two of five isolates of Pen. brevicompactum produced mycophenolic acid. From five out of six isolates of Alternaria spp., alternariol and alternariol monomethyl ether were detected. From Ulocladium spp., Paecilomyces spp., and Asp. ustus no known mycotoxins were detected, although the latter two are known mycotoxin producers. Asp. niger produced several naphtho--pyrones and tetra-cyclic compounds. All investigated species, especially Asp. ustus and Asp. niger produced many unknown secondary metabolites on the building materials. Analyses of wallpaper and glass-fibre wallpaper naturally infested with Asp. versicolor revealed sterigmatocystin and 5-methoxysterigmatocystin. Analyses of naturally infested wallpaper showed that C. globosum produced the chaetoglobosins A and C, and Pen. chrysogenum produced the antibiotic meleagrin.This revised version was published online in October 2005 with corrections to the Cover Date.     

Rhizosphere and phyllosphere fungi of four fern plants growing in Saudi Arabia

Seventy-eight species in addition to 1 variety of A. flavus belonging to 31 genera were collected from the rhizosphere (55 species + 1 variety and 24 genera) and phyllosphere (59 species and 22 genera) of Adiantum capillus-veneris, Ceterach officinarum, Asplenium filare and Cheilanthes catanensis.In the rhizosphere, the most common genera were Aspergillus, Penicillium, Fusarium, Mucor and yeasts. In the phyllosphere, the most prevalent fungi were Cladosporium herbarum, C. sphaerospermum, Alternaria alternata, Drechslera spicifera, Aspergillus spp., Penicillium spp., Cephalosporium roseo-griseum, Myrothecium verrucaria, Mucor racemosus and yeasts.     

Fungal flora on board the Mir-Space Station, identification by morphological features and ribosomal DNA sequences

This report is on the morphological and molecular biological identification, using 18S- and ITS1-rDNA sequences, of the "space fungi" isolated on board the Russian Mir-Space Station as the major constituents of the fungal flora. The six fungal strains were isolated from air by using an air sampler or from condensation. Strains were identified as Penicillium chrysogenum, Aspergillus versicolor, or Penicillium sp. by both methods. The species of space fungi were common saprophytic fungi in our living environment, potential pathogens, and allergens. This study concluded that the environment on board the space station Mir allows the growth of potentially pathogenic fungi as true in residential areas on the earth. Therefore, to prevent infection or other health disorders caused by these fungi, easy and reliable methods should be established to survey the fungal flora in a space station.     

Airborne fungal spores in the Campus of Anchieta (La Laguna,Tenerife/Canary Is.)

A quantitative and qualitative study was carried out of the atmospheric fungal propagules in two university buildings in the Campus of Anchieta (La Laguna, Tenerife, Canary Islands, Spain) and in the outdoor atmosphere, in order to ascertain the most abundant fungi and the concentration of spores in the air, as possible sources of respiratory allergies caused by this type of aeroallergens. Sampling was carried out using two kinds of traps (Burkard Personal Culture Sampler and Burkard Personal Slide Sampler), as well as adhesive tape. Sample 1, indoor, identified between 650-320 CFU m -3 depending on the culture medium, with outdoor values between 670-440 CFU m -3 ; sample 2, recorded between 630-80 CFU m -3 inside and 580-300 CFUm -3 in the outdoor atmosphere. The most represented genera were Cladosporium and Penicillium , although the following were also identified: Agaricales, Alternaria, Aspergillus, Botrytis, Drechslera, Coprinus, Curvularia, Chaetomium, Exserohilum, Fusarium, Helminthosporium, Leptosphaeria , Myxomycetes, Paecilomyces, Pleospora, Stemphylium, Tetraploa, Torula and Ulocladium .     

南极乔治王岛的丝状真菌

本文报道从南极乔治王岛26个样品中分离到60株丝状真菌,其中6个样品未分离到任何真菌,经初步鉴定有8属10个种。根据本次温度实验和该地寒冷的气候,只有桔灰青霉(Penicillium aurantiogriseum Dierckx),大毛霉Mucor mucedo(L.)Fres.)和毡状金孢霉(chrysosporium pannorum(Link)Hughes)在本地能生长繁殖。其中毡状金孢霉占明显优势。     

Mycoflora and trichothecene toxins of paddy grains from Egypt

120 species and 38 genera were collected from 64 samples of paddy grains on glucose- and cellulose-Czapek's agar at 28 °C. The total count of glycophilic and cellulose-decomposing fungi fluctuated between 216–29760; and 124–11320 colonies/g paddy grains on the two media, respectively.On glucose agar, the most common species were Aspergillus niger, A. flavus, A. sydowi, A. terreus, A. fumigatus, A. ochraceus, Penicillium chrysogenum, P. corylophilum, Fusarium oxysporum, Alternaria alternata, Cladosporium cladosporioides, Trichoderma viride and Mucor racemosus.On cellulose agar with pH 5.5 & 8.0, the most prevalent fungi were Stachybotrys chartarum, S. bisybi, Aspergillus niger, A. flavus, Fusarium oxysporum, Alternaria alternata, Drechslera sativus and Acremonium strictum.Extracts from 64 paddy samples were tested against brine shrimp larvae (Artemis salina). Of these 9 displayed varying degrees of toxicity. Trichothecene-toxins were detected in the extracts of three paddy samples only. Diacetoxyscirpenol and T-2 toxin were detected in two samples and only T-2 toxin in the other.     

Molecular and morphological identification of fungal species isolated from bealmijang meju

Bealmijang is a short-term aged paste made from meju, which is a brick of fermented soybeans and other ingredients. Different types of bealmijang are available depending on the geographic region or ingredients used. However, no study has clarified the microbial diversity of these types. We identified 17 and 14 fungal species from black soybean meju (BSM) and buckwheat meju (BWM), respectively, on the basis of morphology, culture characteristics, and internal transcribed spacer and beta-tubulin gene sequencing. In both meju, Aspergillus oryzae, Rhizopus oryzae, Penicillium polonicum, P. steckii, Cladosporium tenuissimum, C. cladosporioides, C. uredinicola, and yeast species Pichia burtonii were commonly found. Moreover, A. flavus, A. niger, P. crustosum, P. citrinum, Eurotium niveoglaucum, Absidia corymbifera, Setomelanomma holmii, Cladosporium spp. and unclassified species were identified from BSM. A. clavatus, Mucor circinelloides, M. racemosus, P. brevicompactum, Davidiella tassiana, and Cladosporium spp. were isolated from BWM. Fast growing Zygomycetous fungi is considered important for the early stage of meju fermentation, and A. oryae and A. niger might play a pivotal role in meju fermentation owing to their excellent enzyme productive activities. It is supposed that Penicillium sp. and Pichia burtonii could contribute to the flavor of the final food products. Identification of this fungal diversity will be useful for understanding the microbiota that participate in meju fermentation, and these fungal isolates can be utilized in the fermented foods and biotechnology industries.     

Early detection of spoilage moulds in bread using volatile production patterns and quantitative enzyme assays

AIMS: Early detection of spoilage fungi (two Eurotium spp., a Penicillium chrysogenum species) in bread analogues over periods of 72 h at 25 degrees C and 0.95 water activity was evaluated using volatile production patterns, hydrolytic enzyme production, and changes in fungal populations. METHODS AND RESULTS: Using an electronic nose system it was possible to differentiate between uninoculated controls and samples contaminated with P. chrysogenum within 28 h. After 40-48 h it was possible to differentiate between the Eurotium spp., P. chrysogenum and the control using Principal Component Analysis (PCA). Cluster analyses could differentiate between the control, P. chrysogenum and the Eurotium spp. after 40 h. Of seven hydrolytic enzymes examined after 48 h, the specific activities of three were significantly different from uninoculated control bread. There were also differences between the mould species in production of three enzymes. Penicillium chrysogenum populations increased fastest, from about 10(3) cfu g(-1) to 10(6)-10(7) cfu g(-1) after 72 h. For the Eurotium spp. this increase was slower. CONCLUSIONS: Overall, this study suggests, for the first time, that an electronic nose system using a surface polymer sensor array is able to detect qualitative changes in volatile production patterns for the early detection of the activity of spoilage moulds in bakery products. SIGNIFICANCE AND IMPACT OF THE STUDY: Potential exists for application of such systems for microbial quality assurance in intermediate moisture food products.     

Mycological survey of Korean cereals and production of mycotoxins by Fusarium isolates.

The fungal species isolated from Korean cereals (barley, polished barley, wheat, rye, and malt) were Alternaria spp., Aspergillus spp., Chaetomium spp., Drechslera spp., Epicoccum sp., Fusarium spp., and Penicillium spp., etc. The number of Fusarium strains isolated was 36, and their ability to produce Fusarium mycotoxins on rice was tested. Nivalenol (NIV) was produced by Fusarium graminearum (7 of 9 isolates), Fusarium oxysporum (3 of 10 isolates), and Fusarium spp. (7 of 15 isolates). Of 15 isolates of Fusarium spp., 6 formed deoxynivalenol (DON). Fusarenon-X and 3-acetyl-DON were produced by most NIV- and DON-forming isolates, respectively. Zearalenone was produced by 3 isolates of F. graminearum, 1 isolate of Fusarium equiseti, and 11 isolates of Fusarium spp. T-2 toxin was not produced by any Fusarium isolates. The highest concentrations of mycotoxins produced by Fusarium isolates were 77.4 (NIV), 5.3 (DON), 138.3 (fusarenon-X), 40.6 (3-acetyl-DON), and 23.2 (zearalenone) micrograms/g.